thermal recovery displacement: Topics by WorldWideScience.org

Sample records for thermal recovery displacement

Miscible fluid displacement: an answer to increasing oil recovery

Energy Technology Data Exchange (ETDEWEB)

Rodriguez, N R; Rivera, R J

1976-01-01

This study presents the state of the art on miscible and miscible-type processes. It is well known that when these processes are applied under ideal laboratory conditions, the oil recovery obtained from linear cores approaches 100% of the total oil contained in the porous structure which is contacted by the displacing fluids. In the past few years, a worldwide shortage of crude oil supplies produced an increased interest in new oil recovery methods. Because of this situation, the oil industry turned its eyes back toward the miscible processes. This study discusses the following miscible fluid displacement processes: (1) high-pressure dry gas displacement; (2) enriched gas displacement; (3) GLP slug flooding; and (4) carbon dioxide displacement. In addition to the processes aforementioned, this work presents the main features of the micellar solution flooding process. (17 refs.)
Thermal energy storage for industrial waste heat recovery

Science.gov (United States)

Hoffman, H. W.; Kedl, R. J.; Duscha, R. A.

1978-01-01

The potential is examined for waste heat recovery and reuse through thermal energy storage in five specific industrial categories: (1) primary aluminum, (2) cement, (3) food processing, (4) paper and pulp, and (5) iron and steel. Preliminary results from Phase 1 feasibility studies suggest energy savings through fossil fuel displacement approaching 0.1 quad/yr in the 1985 period. Early implementation of recovery technologies with minimal development appears likely in the food processing and paper and pulp industries; development of the other three categories, though equally desirable, will probably require a greater investment in time and dollars.
Instrumentation and control systems for monitoring and data acquisition for thermal recovery process

Energy Technology Data Exchange (ETDEWEB)

Aparicio, J.; Hernandez, E.; Perozo, H. [PDVSA Intevep, S.A. (Venezuela)

2011-07-01

Thermal recovery methods are often applied to enhance oil recovery in heavy oil reservoirs, one of its challenges is to control the displacement of the thermal front. Methods are thus implemented to obtain data on the temperatures in the wells at any given time and to monitor other variables so that the behaviour of the thermal front can be predicted. The aim of this paper is to present a new control and instrumentation scheme to measure all of the variables. A software was created using Labview a graphs-based programming language software and PostgreSQL, a database management system. Using this software, sensors can be added or removed at any time; trends can be immediately visualized; and quality of the information is ensured since there is no human intervention in the data collection or processing. This paper presented a software which improves monitoring of all of the variables affecting the behaviour of the thermal front.
A thermal modelling of displacement cascades in uranium dioxide

Energy Technology Data Exchange (ETDEWEB)

Martin, G., E-mail: guillaume.martin@cea.fr [CEA – DEN/DEC/SESC/LLCC, Bât. 352, 13108 Saint-Paul-Lez-Durance Cedex (France); Garcia, P.; Sabathier, C. [CEA – DEN/DEC/SESC/LLCC, Bât. 352, 13108 Saint-Paul-Lez-Durance Cedex (France); Devynck, F.; Krack, M. [Laboratory for Reactor Physics and Systems Behaviour, Paul Scherrer Institute, CH-5232 Villigen PSI (Switzerland); Maillard, S. [CEA – DEN/DEC/SESC/LLCC, Bât. 352, 13108 Saint-Paul-Lez-Durance Cedex (France)

2014-05-01

The space and time dependent temperature distribution was studied in uranium dioxide during displacement cascades simulated by classical molecular dynamics (MD). The energy for each simulated radiation event ranged between 0.2 keV and 20 keV in cells at initial temperatures of 700 K or 1400 K. Spheres into which atomic velocities were rescaled (thermal spikes) have also been simulated by MD to simulate the thermal excitation induced by displacement cascades. Equipartition of energy was shown to occur in displacement cascades, half of the kinetic energy of the primary knock-on atom being converted after a few tenths of picoseconds into potential energy. The kinetic and potential parts of the system energy are however subjected to little variations during dedicated thermal spike simulations. This is probably due to the velocity rescaling process, which impacts a large number of atoms in this case and would drive the system away from a dynamical equilibrium. This result makes questionable MD simulations of thermal spikes carried out up to now (early 2014). The thermal history of cascades was compared to the heat equation solution of a punctual thermal excitation in UO{sub 2}. The maximum volume brought to a temperature above the melting temperature during the simulated cascade events is well reproduced by this simple model. This volume eventually constitutes a relevant estimate of the volume affected by a displacement cascade in UO{sub 2}. This definition of the cascade volume could also make sense in other materials, like iron.
Thermal recovery gaining importance, says expert

Energy Technology Data Exchange (ETDEWEB)

1964-12-21

In a forecast presented to the Calgary section CIM- AIME at a recent monthly technical meeting, J.V. Howard, Core Labs. Inc., predicted that within the next 2 to 5 yr, California oil production will come from thermal recovery schemes to the extent of 200,000 bpd. One American major oil company is planning a fire flood in a heavy oil reservoir at 12,000 ft depth, where primary recovery is estimated as only 3% of original oil in place. It is estimated that the minimum oil saturation feasible for thermal recovery is 950 bbl per acre-ft. The larger number of variables that will determine the success or failure of thermal recovery makes it essential to have thorough and complete studies of all the thermal processes before one is selected for a given set of reservoir and economic conditions. The number of thermal recovery projects will increase rapidly and the success of any project will depend upon the proper application of experience and technology in thermal recovery.
Stress and Displacement Analysis of Microreactors during Thermal and Vacuum Loading

Science.gov (United States)

2017-09-07

ARL-TR-8121 ● SEP 2017 US Army Research Laboratory Stress and Displacement Analysis of Microreactors during Thermal and Vacuum...is no longer needed. Do not return it to the originator. ARL-TR-8121 ● SEP 2017 US Army Research Laboratory Stress and...TITLE AND SUBTITLE Stress and Displacement Analysis of Microreactors during Thermal and Vacuum Loading 5a. CONTRACT NUMBER 5b. GRANT NUMBER
Rock properties and their effect on thermally-induced displacements and stresses

International Nuclear Information System (INIS)

Chan, T.; Hood, M.; Board, M.

1980-02-01

A discussion is given of the importance of material properties in the finite-element calculations for thermally induced displacements and stresses resulting from a heating experiment in an in-situ granitic rock, at Stripa, Sweden. Comparisons are made between field measurements and finite element method calculations using (1) temperature independent, (2) temperature dependent thermal and thermomechanical properties and (3) in-situ and laboratory measurements for Young's modulus. The calculations of rock displacements are influenced predominantly by the temperature dependence of the thermal expansion coefficient, whereas the dominant factor affecting predictions for rock stresses is the in-situ modulus
Characterizing and modeling the free recovery and constrained recovery behavior of a polyurethane shape memory polymer

International Nuclear Information System (INIS)

Volk, Brent L; Lagoudas, Dimitris C; Maitland, Duncan J

2011-01-01

In this work, tensile tests and one-dimensional constitutive modeling were performed on a high recovery force polyurethane shape memory polymer that is being considered for biomedical applications. The tensile tests investigated the free recovery (zero load) response as well as the constrained displacement recovery (stress recovery) response at extension values up to 25%, and two consecutive cycles were performed during each test. The material was observed to recover 100% of the applied deformation when heated at zero load in the second thermomechanical cycle, and a stress recovery of 1.5–4.2 MPa was observed for the constrained displacement recovery experiments. After the experiments were performed, the Chen and Lagoudas model was used to simulate and predict the experimental results. The material properties used in the constitutive model—namely the coefficients of thermal expansion, shear moduli, and frozen volume fraction—were calibrated from a single 10% extension free recovery experiment. The model was then used to predict the material response for the remaining free recovery and constrained displacement recovery experiments. The model predictions match well with the experimental data
Thermal cycling fatigue of organic thermal interface materials using a thermal-displacement measurement technique

Science.gov (United States)

Steill, Jason Scott

The long term reliability of polymer-based thermal interface materials (TIM) is essential for modern electronic packages which require robust thermal management. The challenge for today's materials scientists and engineers is to maximize the heat flow from integrated circuits through a TIM and out the heat sink. Thermal cycling of the electronic package and non-uniformity in the heat flux with respect to the plan area can lead to void formation and delamination which re-introduces inefficient heat transfer. Measurement and understanding at the nano-scale is essential for TIM development. Finding and documenting the evolution of the defects is dependent upon a full understanding of the thermal probes response to changing environmental conditions and the effects of probe usage. The response of the thermal-displacement measurement technique was dominated by changes to the environment. Accurate measurement of the thermal performance was hindered by the inability to create a model system and control the operating conditions. This research highlights the need for continued study into the probe's thermal and mechanical response using tightly controlled test conditions.
Nonclassicality of Photon-Added Displaced Thermal State via Quantum Phase-Space Distributions

Science.gov (United States)

Zhang, Ran; Meng, Xiang-Guo; Du, Chuan-Xun; Wang, Ji-Suo

2018-02-01

We introduce a new kind of nonclassical mixed state generated by adding arbitrary photons to a displaced thermal state, i.e., the photon-added displaced thermal state (PADTS), and obtain the normalization factor, which is simply related to two-variable Hermite polynomials. We also discuss the nonclassicality of the PADTS by considering quantum phase-space distributions. The results indicate that the value of the photon count statistics is maximum when the number of detected photons is equal to the number of added photons, and that the photon-added operation has a similar modulation effect with increasing displacement. Moreover, the negative volume of the Wigner function for the PADTS takes a maximal value for a specific photon-added number.
Coabsorbent and thermal recovery compression heat pumping technologies

CERN Document Server

Staicovici, Mihail-Dan

2014-01-01

This book introduces two of the most exciting heat pumping technologies, the coabsorbent and the thermal recovery (mechanical vapor) compression, characterized by a high potential in primary energy savings and environmental protection. New cycles with potential applications of nontruncated, truncated, hybrid truncated, and multi-effect coabsorbent types are introduced in this work. Thermal-to-work recovery compression (TWRC) is the first of two particular methods explored here, including how superheat is converted into work, which diminishes the compressor work input. In the second method, thermal-to-thermal recovery compression (TTRC), the superheat is converted into useful cooling and/or heating, and added to the cycle output effect via the coabsorbent technology. These and other methods of discharge gas superheat recovery are analyzed for single-, two-, three-, and multi-stage compression cooling and heating, ammonia and ammonia-water cycles, and the effectiveness results are given. The author presen...
Displacer Diameter Effect in Displacer Pulse Tube Refrigerator

Science.gov (United States)

Zhu, Shaowei

2017-12-01

Gas driving displacer pulse tube refrigerators are one of the work recovery type of pulse tube refrigerators whose theoretical efficiency is the same as Stirling refrigerators'. Its cooling power is from the displacement of the displacer. Displace diameter, rod diameter and pressure drop of the regenerator influence the displacement, which are investigated by numerical simulation. It is shown that the displacement ratio of the displacer over the piston is almost not affected by the displacer diameter at the same rod diameter ratio, or displacer with different diameters almost has the same performance.
Improved vertical displacements induced by a refined thermal expansion model and its quantitative analysis in GPS height time series

Science.gov (United States)

Wang, Kaihua; Chen, Hua; Jiang, Weiping; Li, Zhao; Ma, Yifang; Deng, Liansheng

2018-04-01

There are apparent seasonal variations in GPS height time series, and thermal expansion is considered to be one of the potential geophysical contributors. The displacements introduced by thermal expansion are usually derived without considering the annex height and underground part of the monument (e.g. located on roof or top of the buildings), which may bias the geophysical explanation of the seasonal oscillation. In this paper, the improved vertical displacements are derived by a refined thermal expansion model where the annex height and underground depth of the monument are taken into account, and then 560 IGS stations are adopted to validate the modeled thermal expansion (MTE) displacements. In order to evaluate the impact of thermal expansion on GPS heights, the MTE displacements of 80 IGS stations with less data discontinuities are selected to compare with their observed GPS vertical (OGV) displacements with the modeled surface loading (MSL) displacements removed in advance. Quantitative analysis results show the maximum annual and semiannual amplitudes of the MTE are 6.65 mm (NOVJ) and 0.51 mm (IISC), respectively, and the maximum peak-to-peak oscillation of the MTE displacements can be 19.4 mm. The average annual amplitude reductions are 0.75 mm and 1.05 mm respectively after removing the MTE and MSL displacements from the OGV, indicating the seasonal oscillation induced by thermal expansion is equivalent to >75% of the impact of surface loadings. However, there are rarely significant reductions for the semiannual amplitude. Given the result in this study that thermal expansion can explain 17.3% of the annual amplitude in GPS heights on average, it must be precisely modeled both in GPS precise data processing and GPS time series analysis, especially for those stations located in the middle and high latitudes with larger annual temperature oscillation, or stations with higher monument.
Large displacement spring-like electro-mechanical thermal actuators with insulator constraint beams

Science.gov (United States)

Luo, J. K.; Fu, Y. Q.; Flewitt, A. J.; Spearing, S. M.; Fleck, N. A.; Milne, W. I.

2005-07-01

A number of in-plane spring-like micro-electro-thermal-actuators with large displacements were proposed. The devices take the advantage of the large difference in the thermal expansion coefficients between the conductive arms and the insulator clamping beams. The constraint beams in one type (the spring) of these devices are horizontally positioned to restrict the expansion of the active arms in the x-direction, and to produce a displacement in the y-direction only. In other two types of actuators (the deflector and the contractor), the constraint beams are positioned parallel to the active arms. When the constraint beams are on the inside of the active arms, the actuator produces an outward deflection in the y-direction. When they are on the outside of the active arms, the actuator produces an inward contraction. Analytical model and finite element analysis were used to simulate the performances. It showed that at a constant temperature, analytical model is sufficient to predict the displacement of these devices. The displacements are all proportional to the temperature and the number of the chevron sections. A two-mask process is under development to fabricate these devices, using Si3N4 as the insulator beams, and electroplated Ni as the conductive beams.
Field survey of occupants thermal comfort in rooms with displacement ventilation

DEFF Research Database (Denmark)

Pitchurov, G.; Naidenov, K.; Melikov, Arsen Krikor

2002-01-01

Field survey of occupants´ response to the thermal environment in eight office buildings with displacement ventilation was performed. The response of 227 occupants (94 males and 133 females) was collected and analysed. A neutral thermal sensation was reported by 37% of the occupants, and between...... slightly cool and slightly warm by more than 85% of the occupants. The occupants´ thermal sensation was close to the predictions by the PMV index. About 24% of the surveyed occupants complained that they were daily bothered by draught mainly at lower leg. Presence of draught discomfort was verified even...
Displacements of Metallic Thermal Protection System Panels During Reentry

Science.gov (United States)

Daryabeigi, Kamran; Blosser, Max L.; Wurster, Kathryn E.

2006-01-01

Bowing of metallic thermal protection systems for reentry of a previously proposed single-stage-to-orbit reusable launch vehicle was studied. The outer layer of current metallic thermal protection system concepts typically consists of a honeycomb panel made of a high temperature nickel alloy. During portions of reentry when the thermal protection system is exposed to rapidly varying heating rates, a significant temperature gradient develops across the honeycomb panel thickness, resulting in bowing of the honeycomb panel. The deformations of the honeycomb panel increase the roughness of the outer mold line of the vehicle, which could possibly result in premature boundary layer transition, resulting in significantly higher downstream heating rates. The aerothermal loads and parameters for three locations on the centerline of the windward side of this vehicle were calculated using an engineering code. The transient temperature distributions through a metallic thermal protection system were obtained using 1-D finite volume thermal analysis, and the resulting displacements of the thermal protection system were calculated. The maximum deflection of the thermal protection system throughout the reentry trajectory was 6.4 mm. The maximum ratio of deflection to boundary layer thickness was 0.032. Based on previously developed distributed roughness correlations, it was concluded that these defections will not result in tripping the hypersonic boundary layer.
Recovery of the irradiated JFETs by thermal annealing

International Nuclear Information System (INIS)

Assaf, J.

2007-10-01

Study about the recovering of irradiated JFET transistors has been reported. The JFETs were damaged totally or partially by exposition to Gamma ray and neutrons. Electronics noise has used to evaluate the effect of radiation and the recovery. The study focused on the recovery by thermal annealing, where samples have been heated gradually until 140 centigrade degree (410 K). The recovery ratio given by this method was higher than that resulted from the relaxation method (time recovery) carried out in the room temperature (300 K), especially for Gamma irradiated samples.(author)
Recovery of metal chlorides from their complexes by molten salt displacement

International Nuclear Information System (INIS)

McLaughlin, D.F.; Stoltz, R.A.

1989-01-01

This patent describes a process for recovering zirconium or hafnium chloride from a complex of zirconium or hafnium tetrachloride and phosphorus oxychloride. The process comprising: introducing liquid complex of zirconium or hafnium tetrachloride and phosphorus oxychloride into an upper portion of a feed column containing zirconium or hafnium tetrachloride vapor and phosphorus oxychloride vapor. The liquid complex absorbing zirconium or hafnium tetrachloride vapor and producing a bottoms liquid and also producing a phosphorus oxychloride vapor stripped of zirconium or hafnium tetrachloride; introducing the bottoms liquid into a molten salt containing displacement reactor, the reactor containing molten salt comprising at least 30 mole percent lithium chloride and at least 30 mole percent of at least one other alkali metal chloride, the reactor being heated to 30-450 0 C to displace phosphorus oxychloride from the complex and product zirconium or hafnium tetrachloride vapor and phosphorus oxychloride vapor and zirconium or hafnium tetrachloride-containing molten salt; introducing the zirconium or hafnium tetrachloride vapor and the phosphorus oxychloride vapor into the feed column below the point of introduction of the liquid stream; introducing the zirconium or hafnium tetrachloride containing-molten salt into a recovery vessel where zirconium or hafnium tetrachloride is removed from the molten salt to produce zirconium or hafnium tetrachloride product and zirconium or hafnium chloride-depleted molten salt; and recycling the zirconium or hafnium tetachloride-depleted molten salt to the displacement reactor
Thermal Recovery from Cold-Working in Type K Bare-Wire Thermocouples

Science.gov (United States)

Greenen, A. D.; Webster, E. S.

2017-12-01

Cold-working of most thermocouples has a significant, direct impact on the Seebeck coefficient which can lead to regions of thermoelectric inhomogeneity and accelerated drift. Cold-working can occur during the wire swaging process, when winding the wire onto a bobbin, or during handling by the end user—either accidentally or deliberately. Swaging-induced cold-work in thermocouples, if uniformly applied, may result in a high level of homogeneity. However, on exposure to elevated temperatures, the subsequent recovery process from the cold-working can then result in significant drift, and this can in turn lead to erroneous temperature measurements, often in excess of the specified manufacturer tolerances. Several studies have investigated the effects of cold-work in Type K thermocouples usually by bending, or swaging. However, the amount of cold-work applied to the thermocouple is often difficult to quantify, as the mechanisms for applying the strains are typically nonlinear when applied in this fashion. A repeatable level of cold-working is applied to the different wires using a tensional loading apparatus to apply a known yield displacement to the thermoelements. The effects of thermal recovery from cold-working can then be accurately quantified as a function of temperature, using a linear gradient furnace and a high-resolution homogeneity scanner. Variation in these effects due to differing alloy compositions in Type K wire is also explored, which is obtained by sourcing wire from a selection of manufacturers. The information gathered in this way will inform users of Type K thermocouples about the potential consequences of varying levels of cold-working and its impact on the Seebeck coefficient at a range of temperatures between ˜ 70°C and 600° C. This study will also guide users on the temperatures required to rapidly alleviate the effects of cold-working using thermal annealing treatments.
Monolithic micro-electro-thermal actuator integrated with a lateral displacement sensor

International Nuclear Information System (INIS)

Zhang, Yan; Choi, Young-Soo; Lee, Dong-Weon

2010-01-01

This paper presents monolithically fabricated horizontal thermal actuators integrated with piezoresistive sensors for in situ displacement sensing. The great advantage of a hybrid system is the use of closed feedback control for improving the transient response of a thermal actuator and positioning accuracy. It consists of two 'hot arms' made of doped silicon for Joule heating-induced thermal expansion when a current flow passes through them. The piezoresistor is embedded in the base of the 'cold arm' flexure for monitoring the tip deflection and for performance characterization. This 'cold arm' is not a part of the electrical circuit, which further improves the heat power efficiency and the measurement accuracy. Optimization is achieved mainly through modification of the geometry as well as the fabrication process. The fabricated micro-electro-thermal actuator with an integrated sensor is intended for use as a scanning cantilever in atomic force microscope or as a sample holder to drive the moving object through arrays configuration.

Solar Thermal Enhanced Oil Recovery, (STEOR) Volume 1: Executive summary

Science.gov (United States)

Elzinga, E.; Arnold, C.; Allen, D.; Garman, R.; Joy, P.; Mitchell, P.; Shaw, H.

1980-11-01

Thermal enhanced oil recovery is widely used in California to aid in the production of heavy oils. Steam injection either to stimulate individual wells or to drive oil to the producing wells, is by far the major thermal process today and has been in use for over 20 years. Since steam generation at the necessary pressures (generally below 4000 kPa (580 psia)) is within the capabilities of present day solar technology, it is logical to consider the possibilities of solar thermal enhanced oil recovery (STEOR). The present project consisted of an evaluation of STEOR. Program objectives, system selection, trade-off studies, preliminary design, cost estimate, development plan, and market and economic analysis are summarized.
THERMAL DISPLACEMENT OF CRANKSHAFT AXIS OF SLOW-SPEED MARINE ENGINE

Directory of Open Access Journals (Sweden)

Lech Murawski

2016-08-01

Full Text Available The paper presents analysis of displacement of a crankshaft axis caused by temperature of marine, slow-speed main engine. Information of thermal displacement of a power transmission system axis is significant during a shaft line alignment and a crankshaft springing analysis. Warmed-up main engine is a source of deformations of an engine body as well as a ship hull in the area of an engine room and hence axis of a crankshaft and a shaftline. Engines' producers recommend the model of parallel displacement of the crankshaft axis under the influence of an engine heat. The model gives us the value (one number! of the crankshaft axis displacement in the hot propulsion system's condition. This model may be too simple in some cases. Presented numerical analyses are based on temperature measurements of the main engine body and the ship hull during a sea voyage. The paper presents computations of MAN B&W K98MC type engine (power: 40000 kW, revolutions: 94 rpm mounted on 4500 TEU container ship (length: 290 m. Propulsion system is working in nominal, steady-state conditions; it is the basic assumption during the analyses. Numerical analyses were preformed with usage of Nastran software based on Finite Element Method. The FEM model of the engine body comprised over 800 thousand degree of freedom. Stiffness of the ship hull (mainly double bottom with the foundation was modelled by a simple cuboid. Material properties of that cuboid were determined on the base of separately performed calculations.
Enhancing Low-Grade Thermal Energy Recovery in a Thermally Regenerative Ammonia Battery Using Elevated Temperatures

KAUST Repository

Zhang, Fang

2015-02-13

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA. A thermally regenerative ammonia battery (TRAB) is a new approach for converting low-grade thermal energy into electricity by using an ammonia electrolyte and copper electrodes. TRAB operation at 72°C produced a power density of 236±8 Wm-2, with a linear decrease in power to 95±5 Wm-2 at 23°C. The improved power at higher temperatures was due to reduced electrode overpotentials and more favorable thermodynamics for the anode reaction (copper oxidation). The energy density varied with temperature and discharge rates, with a maximum of 650 Whm-3 at a discharge energy efficiency of 54% and a temperature of 37°C. The energy efficiency calculated with chemical process simulation software indicated a Carnot-based efficiency of up to 13% and an overall thermal energy recovery of 0.5%. It should be possible to substantially improve these energy recoveries through optimization of electrolyte concentrations and by using improved ion-selective membranes and energy recovery systems such as heat exchangers.
Numerical simulation of displacement instabilities of surface grooves on an alumina forming alloy during thermal cycling oxidation

Energy Technology Data Exchange (ETDEWEB)

Li, Feng Xun; Kang, Ki Ju [Chonnam National University, Gwangju (Korea, Republic of); Ding, Jun [Chongqing University of Technology, Chongqing (China)

2009-08-15

Displacement instability of the thermally grown oxide (TGO) is a fundamental source of failure in thermal barrier systems. In this work, a finite element analysis has been performed to analyze the displacement instability occurring at a heat resistant metal with superficial TGO subjected to thermal cycling. Lateral and in-plane growth of the TGO which happens during high temperature is simulated by means of material property change from the substrate metal to the TGO. Most of the material properties including the TGO growth are based on the results experimentally obtained in-house. Results of the finite element analyses agree well with the experimental observation, which proves the accuracy and validity of this simulation. The technique will be useful for future work on more complicated phenomena such as deformation under thermo-mechanical cycling
RESEARCH OIL RECOVERY MECHANISMS IN HEAVY OIL RESERVOIRS

Energy Technology Data Exchange (ETDEWEB)

Anthony R. Kovscek; William E. Brigham

1999-06-01

The United States continues to rely heavily on petroleum fossil fuels as a primary energy source, while domestic reserves dwindle. However, so-called heavy oil (10 to 20{sup o}API) remains an underutilized resource of tremendous potential. Heavy oils are much more viscous than conventional oils. As a result, they are difficult to produce with conventional recovery methods such as pressure depletion and water injection. Thermal recovery is especially important for this class of reservoirs because adding heat, usually via steam injection, generally reduces oil viscosity dramatically. This improves displacement efficiency. The research described here was directed toward improved understanding of thermal and heavy-oil production mechanisms and is categorized into: (1) flow and rock properties; (2) in-situ combustion; (3) additives to improve mobility control; (4) reservoir definition; and (5) support services. The scope of activities extended over a three-year period. Significant work was accomplished in the area of flow properties of steam, water, and oil in consolidated and unconsolidated porous media, transport in fractured porous media, foam generation and flow in homogeneous and heterogeneous porous media, the effects of displacement pattern geometry and mobility ratio on oil recovery, and analytical representation of water influx. Significant results are described.
Enhanced Oil Recovery Using Micron-Size Polyacrylamide Elastic Microspheres (MPEMs): Underlying Mechanisms and Displacement Experiments

KAUST Repository

Yao, Chuanjin; Lei, Guanglun; Hou, Jian; Xu, Xiaohong; Wang, Dan; Steenhuis, Tammo S.

2015-01-01

Micron-size polyacrylamide elastic microsphere (MPEM) is a newly developed profile control and oil displacement agent for enhanced oil recovery in heterogeneous reservoirs. In this study, laboratory experiments were performed to characterize the viscoelastic properties of MPEMs in brine water. A transparent sandpack micromodel was used to observe the microscopic flow and displacement mechanisms, and parallel-sandpack models were used to investigate the profile control and oil displacement performance using MPEMs in heterogeneous reservoirs. The results indicate that MPEMs almost do not increase the viscosity of injection water and can be conveniently injected using the original water injection pipelines. The microscopic profile control and oil displacement mechanisms of MPEMs in porous media mainly behave as selective-plugging in large pores, fluid diversion after MPEMs plugging, oil drainage caused by MPEMs breakthrough, and the mechanism of oil droplets converging into oil flow. MPEMs have a high plugging strength, which can tolerate a long-term water flushing. MPEMs can selectively enter and plug the large pores and pore-throats in high permeability sandpack, but almost do not damage the low permeability sandpack. MPEMs can effectively divert the water flow from the high permeability sandpack to the low permeability sandpack and improve the sweep efficiency of low permeability sandpack and low permeability area in the high permeability sandpack. The results also confirm the dynamic process of profile control and oil displacement using MPEMs in heterogeneous reservoirs.
Enhanced Oil Recovery Using Micron-Size Polyacrylamide Elastic Microspheres (MPEMs): Underlying Mechanisms and Displacement Experiments

KAUST Repository

Yao, Chuanjin

2015-10-12

Micron-size polyacrylamide elastic microsphere (MPEM) is a newly developed profile control and oil displacement agent for enhanced oil recovery in heterogeneous reservoirs. In this study, laboratory experiments were performed to characterize the viscoelastic properties of MPEMs in brine water. A transparent sandpack micromodel was used to observe the microscopic flow and displacement mechanisms, and parallel-sandpack models were used to investigate the profile control and oil displacement performance using MPEMs in heterogeneous reservoirs. The results indicate that MPEMs almost do not increase the viscosity of injection water and can be conveniently injected using the original water injection pipelines. The microscopic profile control and oil displacement mechanisms of MPEMs in porous media mainly behave as selective-plugging in large pores, fluid diversion after MPEMs plugging, oil drainage caused by MPEMs breakthrough, and the mechanism of oil droplets converging into oil flow. MPEMs have a high plugging strength, which can tolerate a long-term water flushing. MPEMs can selectively enter and plug the large pores and pore-throats in high permeability sandpack, but almost do not damage the low permeability sandpack. MPEMs can effectively divert the water flow from the high permeability sandpack to the low permeability sandpack and improve the sweep efficiency of low permeability sandpack and low permeability area in the high permeability sandpack. The results also confirm the dynamic process of profile control and oil displacement using MPEMs in heterogeneous reservoirs.
Evaluation of thermal displacement behavior of high temperature piping system in power-up test of HTTR. No. 1 results up to 20 MW operation

International Nuclear Information System (INIS)

Hanawa, Satoshi; Kojima, Takao; Sumita, Junya; Tachibana, Yukio

2002-03-01

Temperature of the primary cooling system of the High Temperature Engineering Test Reactor, HTTR, becomes very high because the coolant temperature at the reactor outlet reaches 950degC, and 400degC at inlet of the reactor. Therefore, it is important to confirm the thermal displacement behavior of the high temperature piping system in the primary cooling system from the viewpoint of the structural integrity. Moreover, newly designed 3-dimensional floating support system is adopted to the cooling system, it is meaningful to verify the thermal displacement behavior of the piping system applied the 3-dimensional floating support system. In the power-up test (up to 20 MW operation), thermal displacement behavior of the high temperature piping system was measured. This paper describes the experimental and analytical results of thermal displacement characteristics of the high temperature piping system. The results showed that the resistance force induced from the supporting system effects to the thermal displacement behavior of cooling system, and the analytical results have a good agreement with the experimental results by optimizing the resistant force of the floating support system. Additionally, structural integrity at the 30 MW operation was confirmed by the analysis. (author)
Contracts for field projects and supporting research on enhanced oil recovery. Progress review number 87

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-10-01

Approximately 30 research projects are summarized in this report. Title of the project, contract number, company or university, award amount, principal investigators, objectives, and summary of technical progress are given for each project. Enhanced oil recovery projects include chemical flooding, gas displacement, and thermal recovery. Most of the research projects though are related to geoscience technology and reservoir characterization.
Applications of thermal energy storage to waste heat recovery in the food processing industry

Science.gov (United States)

Wojnar, F.; Lunberg, W. L.

1980-01-01

A study to assess the potential for waste heat recovery in the food industry and to evaluate prospective waste heat recovery system concepts employing thermal energy storage was conducted. The study found that the recovery of waste heat in canning facilities can be performed in significant quantities using systems involving thermal energy storage that are both practical and economical. A demonstration project is proposed to determine actual waste heat recovery costs and benefits and to encourage system implementation by the food industry.
Displacement Ventilation in a Room with Low-Level Diffusers

DEFF Research Database (Denmark)

Nielsen, Peter V.

Ventilation systems with vertical displacement flow have been used in industrial areas with high thermal loads for many years. Quite resently the vertical displacement flow systems have grown popular as comfort ventilation in rooms with thermal loads e.g. offices.......Ventilation systems with vertical displacement flow have been used in industrial areas with high thermal loads for many years. Quite resently the vertical displacement flow systems have grown popular as comfort ventilation in rooms with thermal loads e.g. offices....
Thermal conductivity degradation of graphites due to neutron irradiation at low temperature

International Nuclear Information System (INIS)

Snead, L.L.; Burchell, T.D.

1995-01-01

Several graphites and carbon/carbon composites (C/C's) have been irradiated with fission neutrons near 150 C and at fluences up to a displacement level of 0.24 dpa. The unirradiated room temperature thermal conductivity of these materials varied from 114 W/m K for H-451 isotropic graphite, to 670 W/m K for a unidirectional FMI-1D C/C composite. At the irradiation temperature a saturation reduction in thermal conductivity was seen to occur at displacement levels of approximately 0.1 dpa. All materials were seen to degrade to approximately 10 to 14% of their original thermal conductivity after irradiation. The significant recovery of thermal conductivity due to post-irradiation isochronal anneals is also presented. (orig.)
Cooling energy efficiency and classroom air environment of a school building operated by the heat recovery air conditioning unit

International Nuclear Information System (INIS)

Wang, Yang; Zhao, Fu-Yun; Kuckelkorn, Jens; Liu, Di; Liu, Li-Qun; Pan, Xiao-Chuan

2014-01-01

The recently-built school buildings have adopted novel heat recovery ventilator and air conditioning system. Heat recovery efficiency of the heat recovery facility and energy conservation ratio of the air conditioning unit were analytically modeled, taking the ventilation networks into account. Following that, school classroom displacement ventilation and its thermal stratification and indoor air quality indicated by the CO 2 concentration have been numerically modeled concerning the effects of delivering ventilation flow rate and supplying air temperature. Numerical results indicate that the promotion of mechanical ventilation rate can simultaneously boost the dilution of indoor air pollutants and the non-uniformity of indoor thermal and pollutant distributions. Subsequent energy performance analysis demonstrates that classroom energy demands for ventilation and cooling could be reduced with the promotion of heat recovery efficiency of the ventilation facility, and the energy conservation ratio of the air conditioning unit decreases with the increasing temperatures of supplying air. Fitting correlations of heat recovery ventilation and cooling energy conservation have been presented. - Highlights: • Low energy school buildings and classroom environment. • Heat recovery facility operating with an air conditioning unit. • Displacement ventilation influenced by the heat recovery efficiency. • Energy conservation of cooling and ventilation through heat recovery. • Enhancement of classroom environment with reduction of school building energy
Activities of the Oil Implementation Task Force, reporting period March--August 1991; Contracts for field projects and supporting research on enhanced oil recovery, reporting period October--December 1990

Energy Technology Data Exchange (ETDEWEB)

1991-10-01

Activities of DOE's Oil Implementation Task Force for the period March--August 1991 are reviewed. Contracts for fields projects and supporting research on enhanced oil recovery are discussed, with a list of related publications given. Enhanced recovery processes covered include chemical flooding, gas displacement, thermal recovery, and microbial recovery.
Contracts for field projects and supporting research on enhanced oil recovery. Progress review No. 82, quarterly report, January--March 1995

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-06-01

This document consists of a list of projects supporting work on oil recovery programs. A publications list and index of companies and institutions is provided. The remaining portion of the document provides brief descriptions on projects in chemical flooding, gas displacement, thermal recovery, geoscience, resource assessment, and reservoir class field demonstrations.
Theoretical modeling for optimizing horizontal production well placement in thermal recovery environments to maximize recovery

Energy Technology Data Exchange (ETDEWEB)

Bourgeois, D.J. [Schlumberger Canada Ltd., Calgary, AB (Canada)

2008-07-01

Heavy oil has a high viscosity and a low API gravity rating. Since it is difficult to get a fluid of this nature to flow, enhanced oil recovery techniques are required to extract the oil from the reservoir. Thermal recovery strategies such as steam assisted gravity drainage (SAGD) and cyclic steam injection stimulation (CSS) can be used. These techniques involve injecting steam into a formation which heats up the fluid in place decreasing its viscosity and allowing it to flow into the producing well bore. In order to maximize hydrocarbon recovery from this type of geological environment, the placement of the horizontal production well bore relative to the base of the reservoir is important. In conventional oil and gas plays, well placement methods involving directional deep resistivity logging while drilling (DDR-LWD) measurements to map formation contacts while drilling have enabled wells to be placed relative to formation boundaries. This paper discussed a study that presented some theoretical resistivity inversion and forward modeling results generated from a three-dimensional geocellular model to confirm that this evolving DDR-LWD technology may be applicable to western Canada's Athabasca heavy oil drilling environments. The paper discussed the effect of well bore position, thermal recovery, and pro-active well placement. Resistivity modeling work flow was also presented. It was concluded that being able to drill a horizontal production well relative to the base of the formation could help minimize abandoned oil ultimately leading to better recovery. 4 refs., 8 figs.
Thermal comfort of seated occupants in rooms with personalized ventilation combined with mixing or displacement ventilation

DEFF Research Database (Denmark)

Forejt, L.; Melikov, Arsen Krikor; Cermak, Radim

2004-01-01

The performance of two personalized ventilation systems combined with mixing or displacement ventilation was studied under different conditions in regard to thermal comfort of seated occupants. The cooling performance of personalized ventilation was found to be independent of room air distribution...
HEAVY AND THERMAL OIL RECOVERY PRODUCTION MECHANISMS

Energy Technology Data Exchange (ETDEWEB)

Anthony R. Kovscek; Louis M. Castanier

2002-09-30

The Stanford University Petroleum Research Institute (SUPRI-A) conducts a broad spectrum of research intended to help improve the recovery efficiency from difficult to produce reservoirs including heavy oil and fractured low permeability systems. Our scope of work is relevant across near-, mid-, and long-term time frames. The primary functions of the group are to conduct direction-setting research, transfer research results to industry, and educate and train students for careers in industry. Presently, research in SUPRI-A is divided into 5 main project areas. These projects and their goals include: (1) Multiphase flow and rock properties--to develop better understanding of the physics of displacement in porous media through experiment and theory. This category includes work on imbibition, flow in fractured media, and the effect of temperature on relative permeability and capillary pressure. (2) Hot fluid injection--to improve the application of nonconventional wells for enhanced oil recovery and elucidate the mechanisms of steamdrive in low permeability, fractured porous media. (3) Mechanisms of primary heavy oil recovery--to develop a mechanistic understanding of so-called ''foamy oil'' and its associated physical chemistry. (4) In-situ combustion--to evaluate the effect of different reservoir parameters on the insitu combustion process. (5) Reservoir definition--to develop and improve techniques for evaluating formation properties from production information. What follows is a report on activities for the past year. Significant progress was made in all areas.
Thermal energy recovery of air conditioning system--heat recovery system calculation and phase change materials development

International Nuclear Information System (INIS)

Gu Zhaolin; Liu Hongjuan; Li Yun

2004-01-01

Latent heat thermal energy storage systems can be used to recover the rejected heat from air conditioning systems, which can be used to generate low-temperature hot water. It decreases not only the consumption of primary energy for heating domestic hot water but also the calefaction to the surroundings due to the rejection of heat from air conditioning systems. A recovery system using phase change materials (PCMs) to store the rejected (sensible and condensation) heat from air conditioning system has been developed and studied, making up the shortage of other sensible heat storage system. Also, PCMs compliant for heat recovery of air conditioning system should be developed. Technical grade paraffin wax has been discussed in this paper in order to develop a paraffin wax based PCM for the recovery of rejected heat from air conditioning systems. The thermal properties of technical grade paraffin wax and the mixtures of paraffin wax with lauric acid and with liquid paraffin (paraffin oil) are investigated and discussed, including volume expansion during the phase change process, the freezing point and the heat of fusion
Thermal comfort analysis of a low temperature waste energy recovery system. SIECHP

Energy Technology Data Exchange (ETDEWEB)

Herrero Martin, R. [Departamento de Ingenieria Termica y de Fluidos, Universidad Politecnica de Cartagena, C/Dr. Fleming, s/n (Campus Muralla), 30202 Cartagena, Murcia (Spain); Rey Martinez, F.J.; Velasco Gomez, E. [Departamento de Ingenieria Energetica y Fluidomecanica, ETSII, Universidad de Valladolid, Paseo del Cauce s/n, 47011 Valladolid (Spain)

2008-07-01

The use of a recovery device is justified in terms of energy savings and environmental concerns. But it is clear that the use of a recovery system also has to lead to controlling indoor environmental quality, nowadays a priority concern. In this article, experimental research has been carried out whose aim is to study the thermal comfort provided by a combined recovery equipment (SIECHP), consisting of a ceramic semi-indirect evaporative cooler (SIEC) and a heat pipe device (HP) to recover energy at low temperature in air-conditioning systems. To characterize this device empirically in terms of thermal comfort (TC), Fanger's predicted mean vote (PMV), draught rate, and vertical air temperature difference were used in this study as the TC criteria. (author)

Effects of a Mixed Zone on TGO Displacement Instabilities of Thermal Barrier Coatings at High Temperature in Gas-Cooled Fast Reactors

Directory of Open Access Journals (Sweden)

Jian Wang

2016-01-01

Full Text Available Thermally grown oxide (TGO, commonly pure α-Al2O3, formed on protective coatings acts as an insulation barrier shielding cooled reactors from high temperatures in nuclear energy systems. Mixed zone (MZ oxide often grows at the interface between the alumina layer and top coat in thermal barrier coatings (TBCs at high temperature dwell times accompanied by the formation of alumina. The newly formed MZ destroys interface integrity and significantly affects the displacement instabilities of TGO. In this work, a finite element model based on material property changes was constructed to investigate the effects of MZ on the displacement instabilities of TGO. MZ formation was simulated by gradually changing the metal material properties into MZ upon thermal cycling. Quantitative data show that MZ formation induces an enormous stress in TGO, resulting in a sharp change of displacement compared to the alumina layer. The displacement instability increases with an increase in the MZ growth rate, growth strain, and thickness. Thus, the formation of a MZ accelerates the failure of TBCs, which is in agreement with previous experimental observations. These results provide data for the understanding of TBC failure mechanisms associated with MZ formation and of how to prolong TBC working life.
Improving Energy Efficiency In Thermal Oil Recovery Surface Facilities

Energy Technology Data Exchange (ETDEWEB)

Murthy Nadella, Narayana

2010-09-15

Thermal oil recovery methods such as Cyclic Steam Stimulation (CSS), Steam Assisted Gravity Drainage (SAGD) and In-situ Combustion are being used for recovering heavy oil and bitumen. These processes expend energy to recover oil. The process design of the surface facilities requires optimization to improve the efficiency of oil recovery by minimizing the energy consumption per barrel of oil produced. Optimization involves minimizing external energy use by heat integration. This paper discusses the unit processes and design methodology considering thermodynamic energy requirements and heat integration methods to improve energy efficiency in the surface facilities. A design case study is presented.
Stress recovery and cyclic behaviour of an Fe-Mn-Si shape memory alloy after multiple thermal activation

Science.gov (United States)

Hosseini, E.; Ghafoori, E.; Leinenbach, C.; Motavalli, M.; Holdsworth, S. R.

2018-02-01

The stress recovery and cyclic deformation behaviour of Fe-17Mn-5Si-10Cr-4Ni-1(V,C) shape memory alloy (Fe-SMA) strips, which are often used for pre-stressed strengthening of structural members, were studied. The evolution of recovery stress under different constraint conditions was studied. The results showed that the magnitude of the tensile stress in the Fe-SMA member during thermal activation can have a signification effect on the final recovery stress. The higher the tensile load in the Fe-SMA (e.g., caused by dead load or thermal expansion of parent structure during heating phase), the lower the final recovery stress. Furthermore, this study investigated the cyclic behaviour of the activated SMA followed by a second thermal activation. Although the magnitude of the recovery stress decreased during the cyclic loading, the second thermal activation could retrieve a significant part of the relaxed recovery stress. This observation suggests that the relaxation of recovery stress during cyclic loading is due to a reversible phase transformation-induced deformation (i.e., forward austenite-to-martensite transformation) rather than an irreversible dislocation-induced plasticity. Retrieval of the relaxed recovery stress by the reactivation process has important practical implications as the prestressing loss in pre-stressed civil structures can be simply recovered by reheating of the Fe-SMA elements.
Heat recovery investigation from dryer–thermal oxidizer system in corn-ethanol plants

International Nuclear Information System (INIS)

Olszewski, Pawel

2015-01-01

In recent years, annual corn ethanol production in the U.S. has exceeded 13,298,000,000 gallons. However, net energy balance for this sector became a subject of controversy in many discussions. The aim of the presented research is an investigation of thermal improvement opportunities in a corn ethanol plant. For this purpose, a complex mathematical model was developed for a dryer–thermal oxidizer system. Three variants were subjected thermodynamic analyses: one state of the art system and two proposed system modifications. The properties of humid gas, a mixture of combustion products and moisture evaporated from distiller's grain, were updated based on the steam properties according to the formulation proposed by the International Association for the Properties of Water and Steam. All calculations were performed by uniquely-developed C++ code. The results indicate major potential for improvement in the following areas: (i) water recovery from humid gas; (ii) heat recovery from moisture condensation – max. 44% of total primary energy usage (TPEU); and (iii) fuel savings by reduction of humid gas flow through a thermal oxidizer – max. 1.4% of TPEU. Also the presented analysis can be a starting point for further modifications in real corn ethanol manufacturing applications, leading towards pilot system implementation. - Highlights: • Mathematical model for dryer–oxidizer system in a corn ethanol plant was proposed. • Three configurations were discussed: with intercooler, regenerator, and recuperator. • Recovery rate of water condensed at various conditions and locations was quantified. • Heat recovery possibilities at various temperatures and locations have been assessed. • Energy savings in thermal oxidizer due to preliminary condensation were calculated
Contracts for field projects and supporting research on enhanced oil recovery. Progress review No. 71, quarter ending June 30, 1992

Energy Technology Data Exchange (ETDEWEB)

1993-06-01

Progress reports are presented for the following tasks: chemical flooding--supporting research; gas displacement--supporting research; thermal recovery--supporting research; geoscience technology; resource assessment technology; microbial technology; and novel technology. A list of available publication is also provided.
Water-rock interaction during diagenesis and thermal recovery, Cold Lake, Alberta

Energy Technology Data Exchange (ETDEWEB)

Abercrombie, H.J.

1988-12-01

Fluid and rocks interact at high temperatures during diagenesis and steam assisted thermal recovery of bitumen from the Clearwater Formation at Cold Lake, Alberta. A study was carried out to assess the effects of natural diagenesis in rocks of the formation, and using these data, to relate the chemical and isotopic compositions of fluids produced during thermal recovery to water-rock interactions occurring in the reservoir. X-ray diffraction (XRD) studies on core from Leming and Marguerite Lake document a variety of diagenetic clays including mixed layer minerals smectite-illite and chlorite-smectite, chlorite, illite, berthierine and kaolinite. A method for internally generating factors to convert clay mineral XRD peak heights to relative weight percents was used. Semi-quantitative results show that smectite-illite is ubiquitous and the most abundant clay present. Details are provided of the diagenetic sequence illustrating water-rock interaction over a prolonged period. Three types of water were found to be produced from the wells: injected water, formation water associated with bitumen, and bottom water from the underlying McMurray Formation. Produced water compositions were used to estimate in-situ temperatures of fluids produced from reservoirs. It is concluded that equilibrium closed-system models can be applied to natural diagenesis and artificial diagenesis induced during thermal recovery. 132 refs., 52 figs., 5 tabs.
Thermal performance analysis of Brayton cycle with waste heat recovery boiler for diesel engines of offshore oil production facilities

International Nuclear Information System (INIS)

Liu, Xianglong; Gong, Guangcai; Wu, Yi; Li, Hangxin

2016-01-01

Highlights: • Comparison of Brayton cycle with WHRB adopted in diesel engines with and without fans by thermal performance. • Waste heat recovery technology for FPSO. • The thermoeconomic analysis for the heat recovery for FPSO. - Abstract: This paper presents the theoretical analysis and on-site testing on the thermal performance of the waste heat recovery system for offshore oil production facilities, including the components of diesel engines, thermal boilers and waste heat boilers. We use the ideal air standard Brayton cycle to analyse the thermal performance. In comparison with the traditional design, the fans at the engine outlet of the waste heat recovery boiler is removed due to the limited space of the offshore platform. The cases with fan and without fan are compared in terms of thermal dynamics performance, energy efficiency and thermo-economic index of the system. The results show that the application of the WHRB increases the energy efficiency of the whole system, but increases the flow resistance in the duct. It is proved that as the waste heat recovery boiler takes the place of the thermal boiler, the energy efficiency of whole system without fan is slightly reduced but heat recovery efficiency is improved. This research provides an important guidance to improve the waste heat recovery for offshore oil production facilities.
Displacement Ventilation

DEFF Research Database (Denmark)

Bjørn, Erik; Mattsson, Magnus; Sandberg, Mats

Full-scale experiments were made in a displacement ventilated room with two breathing thermal manikins to study the effect of movements and breathing on the vertical contaminant distribution, and on the personal exposure of occupants. Concentrations were measured with tracer gas equipment...
Activities of the Oil Implementation Task Force; Contracts for field projects and supporting research on enhanced oil recovery, July--September 1990

Energy Technology Data Exchange (ETDEWEB)

Tiedemann, H.A. (ed.) (USDOE Bartlesville Project Office, OK (USA))

1991-05-01

The report contains a general introduction and background to DOE's revised National Energy Strategy Advanced Oil Recovery Program and activities of the Oil Implementation Task Force; a detailed synopsis of the symposium, including technical presentations, comments and suggestions; a section of technical information on deltaic reservoirs; and appendices containing a comprehensive listing of references keyed to general deltaic and geological aspects of reservoirs and those relevant to six selected deltaic plays. Enhanced recovery processes include chemical floodings, gas displacement, thermal recovery, geoscience, and microbial recovery.
Influence of stability of polymer surfactant on oil displacement mechanism

Science.gov (United States)

Liu, Li; Li, Chengliang; Pi, Yanming; Wu, Di; He, Ying; Geng, Liang

2018-02-01

At present, most of the oilfields of China have entered the late stage of high water-cut development, and three oil recovery technique has become the leading technology for improving oil recovery. With the improvement of three oil recovery techniques, the polymer surfactant flooding technology has been widely promoted in oil fields in recent years. But in the actual field experiment, it has been found that the polymer surfactant has chromatographic separation at the extraction end, which indicates that the property of the polymer surfactant has changed during the displacement process. At present, there was few literature about how the stability of polymer surfactant affects the oil displacement mechanism. This paper used HuaDing-I polymer surfactant to conduct a micro photolithography glass flooding experiment, and then compared the oil displacement law of polymer surfactant before and after static setting. Finally, the influence law of stability of polymer surfactant on the oil displacement mechanism is obtained by comprehensive analysis.
Numerical modelling of fracture displacements due to thermal load from a KBS-3 repository

Energy Technology Data Exchange (ETDEWEB)

Hakami, Eva; Olofsson, Stig-Olof [Itasca Geomekanik AB, Stockholm (Sweden)

2002-01-01

The objective of the project has been to estimate the largest shear displacements that could be expected on a pre-existing fracture located in the repository area, due to the heat release from the deposited waste. Two-dimensional numerical analyses using the 'Universal Distinct Element Code' (UDEC) have been performed. The UDEC models represent a vertical cross section of a KBS-3 type repository with a large planar fracture intersecting a deposition hole at the repository centre. The extension, dip and mechanical properties of the fracture were changed in different models to evaluate the influence of these parameters on fracture shear displacements. The fracture was modelled using a Coulomb slip criterion with no cohesion and no dilation. The rock mass surrounding the fracture was modelled as a homogeneous, isotropic and elastic material, with a Young's modulus of 40 GPa. The initial heat release per unit repository area was assumed to be 8W/m{sup 2} (total power/total repository area). The shear displacements occur due to the thermal expansion of the rock surrounding the heat generating canisters. The rock mass is almost free to expand vertically, but is constrained horizontally, which gives a temperature-induced addition of shear stresses in the plane of the fracture. The shear movement of the fracture therefore follows the temperature development in the surrounding rock and the maximum shear displacement develops about 200 years after the waste deposition. Altogether, twenty cases are analysed. The maximum shear displacement, which occurs at the fracture centre, amounts to 0.2-13.8 cm depending on the fracture parameters. Among the analysed cases, the largest shear values, about 13 cm, was calculated for the cases with about 700 m long fractures with a shear stiffness of 0.005 GPa/m. Also, for large fractures with a higher shear stiffness of 5 GPa/m, but with a low friction angle (15 deg), the shear displacement reaches similar magnitudes, about
Thermal enhanced oil recovery in Indonesia. Prospect of HTGR application

International Nuclear Information System (INIS)

Rahman, M.; Sumardiono; Lasman, A.N.; Sudarto; Prihardany, D.

1997-01-01

In the next future, Indonesia will face oil scarcity. The present reserves are estimated to be depleted in 20 years. However, after primary and secondary recovery processes, there are still more than 50% of original oil in place remaining in the reservoir, and this could be recovered by using tertiary recovery method or which is known as enhanced oil recovery (EOR) processes. Among the three major methods of EOR, steam flooding is a thermal recovery method into which High Temperature Reactor (HTR) module can be integrated for producing steam. However, the feasibility of application of HTR as an alternative to conventional oil-fired steam generator will depend strongly on the price of oil. This paper discusses EOR screening for Indonesian oil fields to identify the appropriate oil reservoirs for steam flooding application as well as the possibility of steam supply by HTR module. Also reviewed is the previous study on HTR application for Duri Steam Flood Project. (author). 8 refs, 6 figs, 5 tabs
Study on a heat recovery system for the thermal power plant utilizing air cooling island

International Nuclear Information System (INIS)

Sun, Jian; Fu, Lin; Sun, Fangtian; Zhang, Shigang

2014-01-01

A new heat recovery system for CHP (combined heat and power) systems named HRU (heat recovery unit) is presented, which could recover the low grade heat of exhausted steam from the turbine at the thermal power plant directly. Heat recovery of exhausted steam is often accomplished by recovering the heat of cooling water in current systems. Therefore, two processes of heat transfer is needed at least. However, exhausted steam could be condensed in the evaporator of HRU directly, which reduce one process of heat transfer. A special evaporator is designed condense the exhausted steam directly. Simulated results are compared to experiments, which could include the calculation of heat transfer coefficients of different parts of HRU. It is found that about 25Mw of exhausted steam is recovered by this system. HRU could be promising for conventional CHP systems, which could increase the total energy efficiency obviously and enlarge the heating capacity of a built CHP system. - Highlights: • A new heat recovery system for thermal power plant is presented. • A mathematical model including heat transfer coefficients calculation is given. • This heat recovery system is experimented at a thermal power plant. • Performances of this system under different working conditions are simulated
Factors influencing the life cycle burdens of the recovery of energy from residual municipal waste.

Science.gov (United States)

Burnley, Stephen; Coleman, Terry; Peirce, Adam

2015-05-01

A life cycle assessment was carried out to assess a selection of the factors influencing the environmental impacts and benefits of incinerating the fraction of municipal waste remaining after source-separation for reuse, recycling, composting or anaerobic digestion. The factors investigated were the extent of any metal and aggregate recovery from the bottom ash, the thermal efficiency of the process, and the conventional fuel for electricity generation displaced by the power generated. The results demonstrate that incineration has significant advantages over landfill with lower impacts from climate change, resource depletion, acidification, eutrophication human toxicity and aquatic ecotoxicity. To maximise the benefits of energy recovery, metals, particularly aluminium, should be reclaimed from the residual bottom ash and the energy recovery stage of the process should be as efficient as possible. The overall environmental benefits/burdens of energy from waste also strongly depend on the source of the power displaced by the energy from waste, with coal giving the greatest benefits and combined cycle turbines fuelled by natural gas the lowest of those considered. Regardless of the conventional power displaced incineration presents a lower environmental burden than landfill. Copyright © 2015 Elsevier Ltd. All rights reserved.
Improvement in deuterium recovery from water–isotope mixture by thermal diffusion in the device of branch columns

International Nuclear Information System (INIS)

Hsu, Ching-Chun; Yeh, Ho-Ming

2014-01-01

Highlights: • Recovery of deuterium by thermal diffusion from water–isotope mixture has been investigated. • The undesirable remixing effect can be reduced by employing the device of branch columns. • Deuterium recoveries were compared with that in a single column of the same total column length. • Considerable recovery improvement is obtainable in the device of branch columns, instead of in a single-column device. - Abstract: Deuterium recovery from water–isotopes mixture using thermal diffusion can be improved by employing the branch column device, instead of single column devices, with the same total column length. The remixing effect due to convection currents in a thermal diffusion column for heavy water enrichment is thus reduced and separation improvement increases when the flow rate or the total column length increases. The improvement in separation can reach about 50% for the numerical example given
Contracts for field projects and supporting research on enhanced oil recovery, October--December 1992. Progress review No. 73, quarter ending December 31, 1992

Energy Technology Data Exchange (ETDEWEB)

1993-12-01

Accomplishments for this quarter ending December 31, 1992 are presented for the following tasks: chemical flooding--supporting research; gas displacement--supporting research; thermal recovery--supporting research; geoscience technology; resource assessment technology; microbial technology; reservoir classes; and novel technology.
A review of technologies and performances of thermal treatment systems for energy recovery from waste

Energy Technology Data Exchange (ETDEWEB)

Lombardi, Lidia, E-mail: lidia.lombardi@unicusano.it [Niccolò Cusano University, via Don Carlo Gnocchi, 3, 00166 Rome (Italy); Carnevale, Ennio [Industrial Engineering Department, University of Florence, via Santa Marta, 3, 50129 Florence (Italy); Corti, Andrea [Department of Information Engineering and Mathematics, University of Siena, via Roma, 56, 53100 (Italy)

2015-03-15

Highlights: • The topic of energy recovery from waste by thermal treatment is reviewed. • Combustion, gasification and pyrolysis were considered. • Data about energy recovery performances were collected and compared. • Main limitations to high values of energy performances were illustrated. • Diffusion of energy recovery from waste in EU, USA and other countries was discussed. - Abstract: The aim of this work is to identify the current level of energy recovery through waste thermal treatment. The state of the art in energy recovery from waste was investigated, highlighting the differences for different types of thermal treatment, considering combustion/incineration, gasification and pyrolysis. Also different types of wastes – Municipal Solid Waste (MSW), Refuse Derived Fuel (RDF) or Solid Refuse Fuels (SRF) and some typologies of Industrial Waste (IW) (sludge, plastic scraps, etc.) – were included in the analysis. The investigation was carried out mainly reviewing papers, published in scientific journals and conferences, but also considering technical reports, to gather more information. In particular the goal of this review work was to synthesize studies in order to compare the values of energy conversion efficiencies measured or calculated for different types of thermal processes and different types of waste. It emerged that the dominant type of thermal treatment is incineration associated to energy recovery in a steam cycle. When waste gasification is applied, the produced syngas is generally combusted in a boiler to generate steam for energy recovery in a steam cycle. For both the possibilities – incineration or gasification – cogeneration is the mean to improve energy recovery, especially for small scale plants. In the case of only electricity production, the achievable values are strongly dependent on the plant size: for large plant size, where advanced technical solutions can be applied and sustained from an economic point of view, net
Human response to ductless personalized ventilation coupled with displacement ventilation

DEFF Research Database (Denmark)

Dalewski, Mariusz; Veselý, Michal; Melikov, Arsen K.

2012-01-01

A human subject experiment was carried out to investigate the extent to which ductless personalized ventilation (DPV) in conjunction with displacement ventilation can improve perceived air quality (PAQ) and thermal comfort at elevated room air temperature in comparison with displacement ventilation...... alone. The experimental conditions comprised displacement ventilation alone (room air temperature of 23 °C, 26 °C, 29 °C) and DPV with displacement ventilation (26 °C, 29 °C), both operating at supply air temperatures 3, 5 or 6K lower than room air temperature, as well as mixing ventilation (23 °C, 3 K......). During one hour exposure participants answered questionnaires regarding PAQ and thermal comfort. PAQ was significantly better with DPV than without DPV at the same background conditions. Thermal comfort improved when DPV was used. Combining DPV with displacement ventilation showed the potential...
Performance of displacement ventilation in practice

DEFF Research Database (Denmark)

Naidenov, K.; Pitchurov, G.; Langkilde, Gunnar

2002-01-01

This paper presents results of a field study in offices with displacement ventilation. It comprises detailed physical measurements of the thermal environment and collection of occupants´ response at 227 workplaces. The results, both physical measurements and human response, identified draught...... as the major local discomfort in the rooms with displacement ventilation. Twenty-three percent of the occupants were daily bothered by draught. In some buildings the maintenance personnel tried to improve occupants´ thermal comfort by raising the supply air temperature or office workers themselves blocked...
Contracts for field projects and supporting research on enhanced oil recovery, July--September 1992. Progress review No. 72, quarter ending September 30, 1992

Energy Technology Data Exchange (ETDEWEB)

1993-09-01

Accomplishments for the past quarter are presented for the following tasks: Chemical flooding--supporting research; gas displacement--supporting research; thermal recovery--supporting research; geoscience technology; resource assessment technology; microbial technology; and novel technology. A list of available publication is also provided.

Thermal effect of lubricating oil in positive-displacement air compressors

International Nuclear Information System (INIS)

Valenti, Gianluca; Colombo, Luigi; Murgia, Stefano; Lucchini, Andrea; Sampietro, Andrea; Capoferri, Andrea; Araneo, Lucio

2013-01-01

The isentropic efficiency of positive-displacement compressors may be improved in order to follow an increasing demand for energy savings. This work analyzes the thermal effect of the lubricating oil presence in the air during compression with the scope of exploiting it as a thermal ballast to mitigate both the gas temperature rise and its compression work. The bibliographic review shows that other authors suggested that oil can have positive effects if properly injected. Here an energy balance analysis is executed with the scope of deriving relations for the gas–liquid compression in analogy with those typical for the gas-only compression and of confirming that ideally the liquid presence may have beneficial effects, making the gas–liquid compression even better than 1- and 2-time intercooled gas compressions. Given these positive results, a heat transfer analysis is conducted to model the thermal interaction between gas and oil droplets within a mid-size rotary vane air compressor. A droplet diameter of the order of 100 μm leads to large reductions of both temperature increase and compression work: air can exit the discharge port at a temperature as low as 60 °C and compression work can be lowered by 23–28% with respect to conventional compressors. Finally, a test rig is constructed and operated to investigate a large-flow and large-angle oil nozzle taken from the market showing that, at the operating conditions of a compressor, oil breaks up into small droplets and undefined structures with large exchange surfaces. -- Highlights: ► Exploitation of thermal effect of oil in gas compressors is assessed numerically. ► Oil in 100 μm-diameter droplets mitigates effectively the gas temperature rise. ► Discharge temperature and compression work result to be much smaller than typical. ► An experimental setup is used to investigate oil atomization via commercial nozzles. ► A tested nozzle creates fine oil droplets and structures at conditions of
Calculated thermally induced displacements and stresses for heater experiments at Stripa, Sweden. Linear thermoelastic models using constant material properties

International Nuclear Information System (INIS)

Chan, T.; Cook, N.G.W.

1979-12-01

Thermally induced displacements and stresses have been calculated by finite element analysis to guide the design, operation, and data interpretation of the in situ heating experiments in a granite formation at Stripa, Sweden. There are two full-scale tests with electrical heater canisters comparable in size and power to those envisaged for reprocessed high level waste canisters and a time-scaled test. To provide a simple theoretical basis for data analysis, linear thermoelasticity was assumed. Constant (temperature-independent) thermal and mechanical rock properties were used in the calculations. These properties were determined by conventional laboratory testing on small intact core specimens recovered from the Stripa test site. Two-dimensional axisymmetric models were used for the full-scale experiments, and three-dimensional models for the time-scaled experiment. Highest compressive axial and tangential stresses are expected at the wall of the heater borehole. For the 3.6 kW full-scale heated experiment, maximum compressive tangential stress was predicted to be below the unconfined compressive strength of Stripa granite, while for the 5 kW experiment, the maximum was approximately equal to the compressive strength before the concentric ring of eight 1 kW peripheral heaters was activated, but would exceed that soon afterwards. Three zones of tensile thermomechanical stresses will occur in each full-scale experiment. Maximum vertical displacements range from a fraction of a millimeter over most of the instrumented area of the time-scaled experiment to a few millimeters in the higher-power full-scale experiment. Radial displacements are typically half or less than vertical displacements. The predicted thermomechanical displacements and stresses have been stored in an on-site computer to facilitate instant graphic comparison with field data as the latter are collected
Contracts for field projects and supporting research on enhanced oil recovery. Progress review number 86, quarter ending March 31, 1996

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-05-01

Summaries are presented for 37 enhanced oil recovery contracts being supported by the Department of Energy. The projects are grouped into gas displacement methods, thermal recovery methods, geoscience technology, reservoir characterization, and field demonstrations in high-priority reservoir classes. Each summary includes the objectives of the project and a summary of the technical progress, as well as information on contract dates, size of award, principal investigator, and company or facility doing the research.
Contracts for field projects and supporting research on enhanced oil recovery. Progress review number 83, quarter ending June 30, 1995

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-08-01

Summaries of 41 research projects on enhanced recovery are presented under the following sections: (1) chemical flooding; (2) gas displacement; (3) thermal recovery; (4) geoscience technology; (5) resource assessment technology; and (6) reservoir classes. Each presentation gives the title of the project, contract number, research facility, contract date, expected completion data, amount of the award, principal investigator, and DOE program manager, and describes the objectives of the project and a summary of the technical progress.
Contracts for field projects and supporting research on enhanced oil recovery: Progress review No. 74, Quarter ending March 31, 1993

Energy Technology Data Exchange (ETDEWEB)

1994-03-01

Accomplishments for the past quarter are presented for the following tasks: chemical flooding--supporting research; gas displacement--supporting research; thermal recovery--supporting research; geoscience technology; resource assessment technology; microbial technology; field demonstrations in high-priority reservoir classes; and novel technology. A list of available publication is also provided.
Generation of a Kind of Displaced Thermal States in the Diffusion Process and its Statistical Properties

Science.gov (United States)

Xiang-Guo, Meng; Hong-Yi, Fan; Ji-Suo, Wang

2018-04-01

This paper proposes a kind of displaced thermal states (DTS) and explores how this kind of optical field emerges using the entangled state representation. The results show that the DTS can be generated by a coherent state passing through a diffusion channel with the diffusion coefficient ϰ only when there exists κ t = (e^{\\hbar ν /kBT} - 1 )^{-1}. Also, its statistical properties, such as mean photon number, Wigner function and entropy, are investigated.
Thermal comfort and ventilation effectiveness in an office room with radiant floor cooling and displacement ventilation

DEFF Research Database (Denmark)

Krajcik, Michal; Tomasi, Roberta; Simone, Angela

2016-01-01

conditions, varying the nominal air change rate from 4.5h-1 down to 1.5h-1. Contaminant removal and mean-age-of-air measurements were performed to characterize the ventilation effectiveness and air velocity; air and operative temperature profiles were measured, together with thermal manikin equivalent...... temperatures, to evaluate the thermal environment. The combined system was able to achieve good ventilation effectiveness close to a heat source, so that in the occupant's breathing zone the ventilation effectiveness was significantly better than for ideal mixing, even at a nominal air change rate as low as 1......% at the highest nominal air change rate of 4.5h-1, even for an occupant sitting 1 meter in front of the supply diffuser, the local thermal discomfort occasioned by the excessive vertical temperature differences gives chilled ceilings the advantage over chilled floors for use with displacement ventilation....
An experimental displacement and over 50 years of tag-recoveries show that monarch butterflies are not true navigators.

Science.gov (United States)

Mouritsen, Henrik; Derbyshire, Rachael; Stalleicken, Julia; Mouritsen, Ole Ø; Frost, Barrie J; Norris, D Ryan

2013-04-30

Monarch butterflies (Danaus plexippus) breeding in eastern North America are famous for their annual fall migration to their overwintering grounds in Mexico. However, the mechanisms they use to successfully reach these sites remain poorly understood. Here, we test whether monarchs are true navigators who can determine their location relative to their final destination using both a "compass" and a "map". Using flight simulators, we recorded the orientation of wild-caught monarchs in southwestern Ontario and found that individuals generally flew in a southwest direction toward the wintering grounds. When displaced 2,500 km to the west, the same individuals continued to fly in a general southwest direction, suggesting that monarchs use a simple vector-navigation strategy (i.e., use a specific compass bearing without compensating for displacement). Using over 5 decades of field data, we also show that the directional concentration and the angular SD of recoveries from tagged monarchs largely conformed to two mathematical models describing the directional distribution of migrants expected under a vector-navigation strategy. A third analysis of tagged recoveries shows that the increasing directionality of migration from north to south is largely because of the presence of geographic barriers that guide individuals toward overwintering sites. Our work suggests that monarchs breeding in eastern North America likely combine simple orientation mechanisms with geographic features that funnel them toward Mexican overwintering sites, a remarkable achievement considering that these butterflies weigh less than a gram and travel thousands of kilometers to a site they have never seen.
Cutaneous blood flow. A comparative study between the thermal recovery method and the radioxenon clearance method

Energy Technology Data Exchange (ETDEWEB)

Tavares, C M; Ferreira, J M; Fernandes, F V

1975-01-01

Since 1968 a thermal recovery method to study the cutaneous circulation has been utilized in the detection of skin circulation changes caused by certain pharmacological agents or by some pathological conditions. This method is based in the determination of the thermal recuperation of a small area of the skin previously cooled. In this work, we want to present the results of a comparative analysis between the thermal recovery method and the clearance of the radioactive xenon injected intracutaneously. The study was performed in the distal extremity of the lower limbs in 16 normal subjects, 16 hyperthyroid patients with increased cutaneous temperature and 11 patients with presumably low cutaneous blood flow (3 patients with hypothyroidism and 8 with obstructive arteriosclerosis).
SolarOil Project, Phase I preliminary design report. [Solar Thermal Enhanced Oil Recovery project

Energy Technology Data Exchange (ETDEWEB)

Baccaglini, G.; Bass, J.; Neill, J.; Nicolayeff, V.; Openshaw, F.

1980-03-01

The preliminary design of the Solar Thermal Enhanced Oil Recovery (SolarOil) Plant is described in this document. This plant is designed to demonstrate that using solar thermal energy is technically feasible and economically viable in enhanced oil recovery (EOR). The SolarOil Plant uses the fixed mirror solar concentrator (FMSC) to heat high thermal capacity oil (MCS-2046) to 322/sup 0/C (611/sup 0/F). The hot fluid is pumped from a hot oil storage tank (20 min capacity) through a once-through steam generator which produces 4.8 MPa (700 psi) steam at 80% quality. The plant net output, averaged over 24 hr/day for 365 days/yr, is equivalent to that of a 2.4 MW (8.33 x 10/sup 6/ Btu/hr) oil-fired steam generator having an 86% availability. The net plant efficiency is 57.3% at equinox noon, a 30%/yr average. The plant will be demonstrated at an oilfield site near Oildale, California.
Methods for enhancing mapping of thermal fronts in oil recovery

Science.gov (United States)

Lee, D.O.; Montoya, P.C.; Wayland, J.R. Jr.

1984-03-30

A method for enhancing the resistivity contrasts of a thermal front in an oil recovery production field as measured by the controlled source audio frequency magnetotelluric (CSAMT) technique is disclosed. This method includes the steps of: (1) preparing a CSAMT-determined topological resistivity map of the production field; (2) introducing a solution of a dopant material into the production field at a concentration effective to alter the resistivity associated with the thermal front; said dopant material having a high cation exchange capacity which might be selected from the group consisting of montmorillonite, illite, and chlorite clays; said material being soluble in the conate water of the production field; (3) preparing a CSAMT-determined topological resistivity map of the production field while said dopant material is moving therethrough; and (4) mathematically comparing the maps from step (1) and step (3) to determine the location of the thermal front. This method is effective with the steam flood, fire flood and water flood techniques.
Sensitivity analysis of recovery efficiency in high-temperature aquifer thermal energy storage with single well

International Nuclear Information System (INIS)

Jeon, Jun-Seo; Lee, Seung-Rae; Pasquinelli, Lisa; Fabricius, Ida Lykke

2015-01-01

High-temperature aquifer thermal energy storage system usually shows higher performance than other borehole thermal energy storage systems. Although there is a limitation in the widespread use of the HT-ATES system because of several technical problems such as clogging, corrosion, etc., it is getting more attention as these issues are gradually alleviated. In this study, a sensitivity analysis of recovery efficiency in two cases of HT-ATES system with a single well is conducted to select key parameters. For a fractional factorial design used to choose input parameters with uniformity, the optimal Latin hypercube sampling with an enhanced stochastic evolutionary algorithm is considered. Then, the recovery efficiency is obtained using a computer model developed by COMSOL Multiphysics. With input and output variables, the surrogate modeling technique, namely the Gaussian-Kriging method with Smoothly Clopped Absolute Deviation Penalty, is utilized. Finally, the sensitivity analysis is performed based on the variation decomposition. According to the result of sensitivity analysis, the most important input variables are selected and confirmed to consider the interaction effects for each case and it is confirmed that key parameters vary with the experiment domain of hydraulic and thermal properties as well as the number of input variables. - Highlights: • Main and interaction effects on recovery efficiency in HT-ATES was investigated. • Reliability depended on fractional factorial design and interaction effects. • Hydraulic permeability of aquifer had an important impact on recovery efficiency. • Site-specific sensitivity analysis of HT-ATES was recommended.
Applications of thermal energy storage to waste heat recovery in the food processing industry

Science.gov (United States)

Trebilcox, G. J.; Lundberg, W. L.

1981-03-01

The canning segment of the food processing industry is a major energy user within that industry. Most of its energy demand is met by hot water and steam and those fluids, in addition to product cooling water, eventually flow from the processes as warm waste water. To minimize the possibility of product contamination, a large percentage of that waste water is sent directly to factory drains and sewer systems without being recycled and in many cases the thermal energy contained by the waste streams also goes unreclaimed and is lost from further use. Waste heat recovery in canning facilities can be performed economically using systems that employ thermal energy storage (TES). A project was proposed in which a demonstration waste heat recovery system, including a TES feature, would be designed, installed and operated.
Activities of the Oil Implementation Task Force, December 1990--February 1991; Contracts for field projects and supporting research on enhanced oil recovery, April--June 1990

Energy Technology Data Exchange (ETDEWEB)

Tiedemann, H.A. (ed.) (USDOE Bartlesville Project Office, OK (USA))

1991-03-01

The Oil Implementation Task Force was appointed to implement the US DOE's new oil research program directed toward increasing domestic oil production by expanded research on near- or mid-term enhanced oil recovery methods. An added priority is to preserve access to reservoirs that have the largest potential for oil recovery, but that are threatened by the large number of wells abandoned each year. This report describes the progress of research activities in the following areas: chemical flooding; gas displacement; thermal recovery; resource assessment; microbial technology; geoscience technology; and environmental technology. (CK)
Heavy metals dispersion during thermal treatment of plastic bags and its recovery.

Science.gov (United States)

Alam, Ohidul; Wang, Sijia; Lu, Wentao

2018-04-15

One of the main worries for thermal treatment of plastic bag (PB) is the air pollution resulting from heavy metal (HM) evaporation and emission. The quest of the study was to investigate their fate during thermal treatment varying with temperature and atmosphere to explore the appropriate treatment technology. Four commonly consumed polymer bags such as PE, HDPE, LDPE and PVC were selected for the analysis. The elemental compositions, heating values and total metal contents of the samples were measured by an elemental analyzer, a sulphur/halogen analyzer, a bomb calorimeter and an ICP-OES, respectively. Thermal treatments of the samples were conducted in a tube furnace at 350, 550, 650, 750, and 850 °C with 1 L/min air or N 2 gas flow, respectively. 5% HNO 3 /10% H 2 O 2 solution was used for absorbing metals from gas phase, and then HM distributions both in flue gas and bottom ash were determined. Results revealed that the lower heating values of HDPE, LDPE, PVC and PE bags were 33.32, 34.28, 24.82 and 36.7 MJ/kg, respectively indicating energy recovery potential. Thermal treatment showed the maximum mass reduction (>90%) of PB at 850 °C. The higher percentage of metals was distributed in ash at initial temperature that promoted to gas with rise of temperature. The used absorption solution exhibited tremendous quantity of metals recovery. However, there was no significant difference between using air and N 2 gas flow during treatment of PB. Copyright © 2018 Elsevier Ltd. All rights reserved.
Analysis of the impact of storage conditions on the thermal recovery efficiency of low-temperature ATES systems

NARCIS (Netherlands)

Bloemendal, Martin; Hartog, Niels

Aquifer thermal energy storage (ATES) is a technology with worldwide potential to provide sustainable space heating and cooling using groundwater stored at different temperatures. The thermal recovery efficiency is one of the main parameters that determines the overall energy savings of ATES systems
Analysis of the impact of storage conditions on the thermal recovery efficiency of low-temperature ATES systems

NARCIS (Netherlands)

Bloemendal, J.M.; Hartog, Niels

2018-01-01

Aquifer thermal energy storage (ATES) is a technology with worldwide potential to provide sustainable space heating and cooling using groundwater stored at different temperatures. The thermal recovery efficiency is one of the main parameters that determines the overall energy savings of ATES systems
Experimental Study on the Properties and Displacement Effects of Polymer Surfactant Solution

Directory of Open Access Journals (Sweden)

Ke-Liang Wang

2013-01-01

Full Text Available Based on the characteristics of oil reservoirs and the requirements of further enhancing oil recovery at high water cut stage of Pubei Oilfield, the displacement performance of polymer surfactant is evaluated. Reasonable injection parameters and oil displacement effects after water flooding are also researched. Compared with conventional polymer with intermediate molecular weight, polymer surfactant has the properties of higher viscosity at low concentration condition and lower interfacial tension. Laboratory experiments indicate that the displacement effect of polymer surfactant is much better than that of conventional polymer at a slug size of 0.57 PV. The oil recovery of polymer surfactant increases by more than 10% after water flooding. Considering the actual situation of low-permeability of Pubei Oilfield reservoirs, the system viscosity of 30 mPa·s is chosen. The corresponding concentration of Type III polymer surfactant is 600 mg/L and the injected slug is 0.57 PV and the oil recovery can be increased by 11.69%.
Optimization of a waste heat recovery system with thermoelectric generators by three-dimensional thermal resistance analysis

International Nuclear Information System (INIS)

Huang, Gia-Yeh; Hsu, Cheng-Ting; Fang, Chun-Jen; Yao, Da-Jeng

2016-01-01

Highlights: • The waste heat recovery system is modeled by three-dimensional thermal resistance. • This is a time-saving and efficient method to estimate power generation from TEGs. • Relations between power generation and varied factors can be rapidly revealed. • TEGs positions and uniformity of velocity profile should be considered together. • Power generation is more sensitive to either internal or external flow velocity. - Abstract: Three-dimensional (3D) thermal resistance analysis provides a rapid and simple method to estimate the power generated from a waste heat recovery system with thermoelectric generators (TEGs), and facilitates an optimization of the system. Such a system comprises three parts – a waste heat recovery chamber, TEG modules and a cooling system. A fin-structured duct serves as a waste heat recovery chamber, which is attached to the hot sides of the TEGs; the cold sides of the TEGs are attached to a cooling system. The waste heat recovery chamber harvests energy from exhaust heat that the TEGs convert into electricity. The estimation of generated power is an important part of the system design. Methods of Computational Fluid Dynamics (CFD) assist the analysis and improve the performance with great accuracy but great computational duration. The use of this method saves much time relative to such CFD methods. In 3D thermal resistance analysis, a node of unknown temperature is located at the centroid of each cell into which the system is divided. The relations of unknown temperatures at the cells are based on the energy conservation and the definition of thermal resistance. The temperatures of inlet waste hot gas and ambient fluid are known. With these boundary conditions, the unknown temperatures in the system are solved, enabling estimation of the power generated with TEGs. A 3D model of the system was simulated with FloTHERM; its numerical solution matched the solution of the 3D thermal resistance analysis within 6%. The power
Chemically evolving systems for oil recovery enhancement in heavy oil deposits

Science.gov (United States)

Altunina, L. K.; Kuvshinov, I. V.; Kuvshinov, V. A.; Stasyeva, L. A.

2017-12-01

This work presents the results of laboratory studies and field tests of new physicochemical technologies for enhanced oil recovery of heavy oil fields under natural development conditions and with thermal-steam stimulation using oil-displacing "smart" systems. The systems are based on surfactants and buffer systems. Their rheological and acid-base properties can be regulated by their chemical evolution directly in the formation. Field tests of the technologies carried out on high-viscosity oil deposit in the Usinskoye oilfield have shown that the EOR technologies are environmentally friendly and technologically effective.

Recovery of condensates from the thermal wood refinement extraction of biomolecules

Energy Technology Data Exchange (ETDEWEB)

Roschitz, C.; Martini, S.; Kleinhappl, M. (Austrian Bioenergy Centre GmbH, Area Gasification, Graz (Austria)); Jenny, M.; Wrulicit, O.A.; Wondrak, A.; Ueberall, E. (Innsbruck University of Medicine, Biocenter, Division of Medical Biochemistry, Innsbruck (Austria)); Fillafer, F.; Steiner, F. (Mafi Holzverarbeitung GmbH, Schneegattern (Austria)); Draxler, J. (Leoben University of Mining and Materials, Institute for Process technology and Industrial Environment Protection, Leoben (Austria))

2007-07-01

Generally the utilisation of woody biomass is dominated by the pulp and paper industry, its use for energy production by combustion or gasification and as a construction material. A large potential of substances could be gained directly and indirectly from biomass. During industrial processes like the thermal wood refinement or the digestion from wood to pulp a large spectrum of substances could be recovered. This paper gives an idea of how to obtain and use those special substances contained in woody biomass. Therefore this project was launched to investigate exhaust vapours originating from industrial wood refining processes. The exhaust vapour of a thermal wood refinement chamber, which works at 150 - 220 deg C, was sampled and its constituents of low amount were investigated. Substance classes like organic acids, aldehydes, esters alcohols, lignin fractions and resin like compounds were identified. The bioactivity of the samples was investigated in biological test procedures, to identify the characteristic pattern of impression (toxicity, antioxidants, gene expression). The technological step of recovery in small ale during the refinery process is under construction and will perform the staged recovery of valuable fractions. The pilot scale plant will give the chance to gain test fractions in sufficient amount to generate materials for application as chemicals, additives for detergents and cleaning agents. (orig.)
Method for thermal recovery of hydrocarbons from an underground formation

Energy Technology Data Exchange (ETDEWEB)

1962-11-13

In a thermal recovery procedure for hydrocarbons from an underground formation, an oxygen-containing gas is injected through at least one input well into the formation. A part of the hydrocarbons in the formation is then ignited and an oxidation front is created. This front moves under the influence of the injected gas to at least one production well in the formation. The temperature in the burning front is higher than approximately 200/sup 0/C but lower than approximately 350/sup 0/C. (4 claims)
The use of salinity contrast for density difference compensation to improve the thermal recovery efficiency in high-temperature aquifer thermal energy storage systems

Science.gov (United States)

van Lopik, Jan H.; Hartog, Niels; Zaadnoordijk, Willem Jan

2016-08-01

The efficiency of heat recovery in high-temperature (>60 °C) aquifer thermal energy storage (HT-ATES) systems is limited due to the buoyancy of the injected hot water. This study investigates the potential to improve the efficiency through compensation of the density difference by increased salinity of the injected hot water for a single injection-recovery well scheme. The proposed method was tested through numerical modeling with SEAWATv4, considering seasonal HT-ATES with four consecutive injection-storage-recovery cycles. Recovery efficiencies for the consecutive cycles were investigated for six cases with three simulated scenarios: (a) regular HT-ATES, (b) HT-ATES with density difference compensation using saline water, and (c) theoretical regular HT-ATES without free thermal convection. For the reference case, in which 80 °C water was injected into a high-permeability aquifer, regular HT-ATES had an efficiency of 0.40 after four consecutive recovery cycles. The density difference compensation method resulted in an efficiency of 0.69, approximating the theoretical case (0.76). Sensitivity analysis showed that the net efficiency increase by using the density difference compensation method instead of regular HT-ATES is greater for higher aquifer hydraulic conductivity, larger temperature difference between injection water and ambient groundwater, smaller injection volume, and larger aquifer thickness. This means that density difference compensation allows the application of HT-ATES in thicker, more permeable aquifers and with larger temperatures than would be considered for regular HT-ATES systems.
A comparison of annual vertical crustal displacements from GPS and Gravity Recovery and Climate Experiment (GRACE) over Europe

Science.gov (United States)

van Dam, T.; Wahr, J.; LavalléE, David

2007-03-01

We compare approximately 3 years of GPS height residuals (with respect to the International Terrestrial Reference Frame) with predictions of vertical surface displacements derived from the Gravity Recovery and Climate Experiment (GRACE) gravity fields for stations in Europe. An annual signal fit to the residual monthly heights, corrected for atmospheric pressure and barotropic ocean loading effects, should primarily represent surface displacements due to long-wavelength variations in water storage. A comparison of the annual height signal from GPS and GRACE over Europe indicates that at most sites, the annual signals do not agree in amplitude or phase. We find that unlike the annual signal predicted from GRACE, the annual signal in the GPS heights is not coherent over the region, displaying significant variability from site to site. Confidence in the GRACE data and the unlikely possibility of large-amplitude small-scale features in the load field not captured by the GRACE data leads us to conclude that some of the discrepancy between the GPS and GRACE observations is due to technique errors in the GPS data processing. This is evidenced by the fact that the disagreement between GPS and GRACE is largest at coastal sites, where mismodeling of the semidiurnal ocean tidal loading signal can result in spurious annual signals.
Mercury recovery from mercury-containing wastes using a vacuum thermal desorption system.

Science.gov (United States)

Lee, Woo Rim; Eom, Yujin; Lee, Tai Gyu

2017-02-01

Mercury (Hg)-containing waste from various industrial facilities is commonly treated by incineration or stabilization/solidification and retained in a landfill at a managed site. However, when highly concentrated Hg waste is treated using these methods, Hg is released into the atmosphere and soil environment. To eliminate these risks, Hg recovery technology using thermal treatment has been developed and commercialized to recover Hg from Hg-containing waste for safe disposal. Therefore, we developed Hg recovery equipment to treat Hg-containing waste under a vacuum of 6.67kPa (abs) at 400°C and recover the Hg. In addition, the dust generated from the waste was separated by controlling the temperature of the dust filtration unit to 230°C. Additionally, water and Hg vapors were condensed in a condensation unit. The Hg removal rate after waste treatment was 96.75%, and the Hg recovery rate as elemental Hg was 75.23%. Copyright © 2016 Elsevier Ltd. All rights reserved.
Geothermal waste heat utilization from in situ thermal bitumen recovery operations.

Science.gov (United States)

Nakevska, Nevenka; Schincariol, Robert A; Dehkordi, S Emad; Cheadle, Burns A

2015-01-01

In situ thermal methods for bitumen extraction introduce a tremendous amount of energy into the reservoirs raising ambient temperatures of 13 °C to as high as 200 °C at the steam chamber edge and 50 °C along the reservoir edge. In essence these operations have unintentionally acted as underground thermal energy storage systems which can be recovered after completion of bitumen extraction activities. Groundwater flow and heat transport models of the Cold Lake, Alberta, reservoir, coupled with a borehole heat exchanger (BHE) model, allowed for investigating the use of closed-loop geothermal systems for energy recovery. Three types of BHEs (single U-tube, double U-tube, coaxial) were tested and analyzed by comparing outlet temperatures and corresponding heat extraction rates. Initial one year continuous operation simulations show that the double U-tube configuration had the best performance producing an average temperature difference of 5.7 °C, and an average heat extraction of 41 W/m. Given the top of the reservoir is at a depth of 400 m, polyethylene piping provided for larger extraction gains over more thermally conductive steel piping. Thirty year operation simulations illustrate that allowing 6 month cyclic recovery periods only increases the loop temperature gain by a factor of 1.2 over continuous operation. Due to the wide spacing of existing boreholes and reservoir depth, only a small fraction of the energy is efficiently recovered. Drilling additional boreholes between existing wells would increase energy extraction. In areas with shallower bitumen deposits such as the Athabasca region, i.e. 65 to 115 m deep, BHE efficiencies should be larger. © 2014, National Ground Water Association.
FOAM3D: A numerical simulator for mechanistic prediciton of foam displacement in multidimensions

Energy Technology Data Exchange (ETDEWEB)

Kovscek, A.R.; Patzek, T.W. [Lawrence Berkeley Laboratory, Berkeley, CA (United States); Radke, C.J. [Univ. of California, Berkeley, CA (United States)

1995-03-01

Field application of foam is a technically viable enhanced oil recovery process (EOR) as demonstrated by recent steam-foam field studies. Traditional gas-displacement processes, such as steam drive, are improved substantially by controlling gas mobility and thereby improving volumetric displacement efficiency. For instance, Patzek and Koinis showed major oil-recovery response after about two years of foam injection in two different pilot studies at the Kern River field. They report increased production of 5.5 to 14% of the original oil in place over a five year period. Because reservoir-scale simulation is a vital component of the engineering and economic evaluation of any EOR project, efficient application of foam as a displacement fluid requires a predictive numerical model of foam displacement. A mechanistic model would also expedite scale-up of the process from the laboratory to the field scale. No general, mechanistic, field-scale model for foam displacement is currently in use.
Research on oil recovery mechanisms in heavy oil reservoirs

Energy Technology Data Exchange (ETDEWEB)

Kovscek, Anthony R.; Brigham, William E., Castanier, Louis M.

2000-03-16

The research described here was directed toward improved understanding of thermal and heavy-oil production mechanisms and is categorized into: (1) flow and rock properties, (2) in-situ combustion, (3) additives to improve mobility control, (4) reservoir definition, and (5) support services. The scope of activities extended over a three-year period. Significant work was accomplished in the area of flow properties of steam, water, and oil in consolidated and unconsolidated porous media, transport in fractured porous media, foam generation and flow in homogeneous and heterogeneous porous media, the effects of displacement pattern geometry and mobility ratio on oil recovery, and analytical representation of water influx.
Energy Efficiency Enhancement of Photovoltaics by Phase Change Materials through Thermal Energy Recovery

Directory of Open Access Journals (Sweden)

Ahmad Hasan

2016-09-01

Full Text Available Photovoltaic (PV panels convert a certain amount of incident solar radiation into electricity, while the rest is converted to heat, leading to a temperature rise in the PV. This elevated temperature deteriorates the power output and induces structural degradation, resulting in reduced PV lifespan. One potential solution entails PV thermal management employing active and passive means. The traditional passive means are found to be largely ineffective, while active means are considered to be energy intensive. A passive thermal management system using phase change materials (PCMs can effectively limit PV temperature rises. The PCM-based approach however is cost inefficient unless the stored thermal energy is recovered effectively. The current article investigates a way to utilize the thermal energy stored in the PCM behind the PV for domestic water heating applications. The system is evaluated in the winter conditions of UAE to deliver heat during water heating demand periods. The proposed system achieved a ~1.3% increase in PV electrical conversion efficiency, along with the recovery of ~41% of the thermal energy compared to the incident solar radiation.
Recovery in stages I and II of thermal and fission neutron irradiated molybdenum

International Nuclear Information System (INIS)

Coltman, R.R. Jr.; Klabunde, C.E.; Redman, J.K.

1975-01-01

The influence of initial dose and irradiation doping upon the recovery of Mo was studied for the markedly different types of damage produced by thermal and fission neutrons. The features of the Stage I recovery commonly seen for several fcc metals can be identified, including a I/sub D/ peak at 40 0 K. The typical dose-dependent behavior of a I/sub E/ subpeak was observed at approximately 47 0 K, and evidence for free interstitial migration is further supported by irradiation doping results. Stage II shows a first-order peak at 120 0 K in which the population percentage increases with increasing initial dose in opposite fashion to fcc impurity detrapping peaks. (auth)
Deformations and Displacements of the LHC Superconducting Dipoles Induced by Standard and Non-Standard Operational Modes

CERN Document Server

La China, M; Gubello, G; Scandale, Walter

2004-01-01

A full-scale and fully-instrumented working model of the LHC lattice cell has been tested at CERN between March and December 2002. Aside of the current, pressure and temperature sensors, controlled by an industrial supervision system, a novel device has been set to monitor magnet positions with respect to the surrounding cryostat. The series of operating modes to test cryogenics, current leads and quench recovery electronics offered the chance to investigate potentially harmful deformations of the superconducting structure. In this paper we present a survey of displacements and deformations experienced by the LHC cell magnets during thermal cycles, current ramps and resistive transitions. Although the system complexity prevented from complete modeling, a preliminary phenomena explanation is given.
Analysis of recovery efficiency in high-temperature aquifer thermal energy storage: a Rayleigh-based method

Science.gov (United States)

Schout, Gilian; Drijver, Benno; Gutierrez-Neri, Mariene; Schotting, Ruud

2014-01-01

High-temperature aquifer thermal energy storage (HT-ATES) is an important technique for energy conservation. A controlling factor for the economic feasibility of HT-ATES is the recovery efficiency. Due to the effects of density-driven flow (free convection), HT-ATES systems applied in permeable aquifers typically have lower recovery efficiencies than conventional (low-temperature) ATES systems. For a reliable estimation of the recovery efficiency it is, therefore, important to take the effect of density-driven flow into account. A numerical evaluation of the prime factors influencing the recovery efficiency of HT-ATES systems is presented. Sensitivity runs evaluating the effects of aquifer properties, as well as operational variables, were performed to deduce the most important factors that control the recovery efficiency. A correlation was found between the dimensionless Rayleigh number (a measure of the relative strength of free convection) and the calculated recovery efficiencies. Based on a modified Rayleigh number, two simple analytical solutions are proposed to calculate the recovery efficiency, each one covering a different range of aquifer thicknesses. The analytical solutions accurately reproduce all numerically modeled scenarios with an average error of less than 3 %. The proposed method can be of practical use when considering or designing an HT-ATES system.
The use of salinity contrast for density difference compensation to improve the thermal recovery efficiency in high-temperature aquifer thermal energy storage systems

NARCIS (Netherlands)

van Lopik, J.H.; Hartog, N.; Zaadnoordijk, Willem Jan

The efficiency of heat recovery in high-temperature (>60 °C) aquifer thermal energy storage (HT-ATES) systems is limited due to the buoyancy of the injected hot water. This study investigates the potential to improve the efficiency through compensation of the density difference by increased salinity
Analysis of an Internal Combustion Engine Using Porous Foams for Thermal Energy Recovery

Directory of Open Access Journals (Sweden)

Mehdi Ali Ehyaei

2016-03-01

Full Text Available Homogeneous and complete combustion in internal combustion engines is advantageous. The use of a porous foam in the exhaust gas in an engine cylinder for heat recovery is examined here with the aim of reducing engine emissions. The internal combustion engine with a porous core regenerator is modeled using SOPHT software, which solved the differential equations for the thermal circuit in the engine. The engine thermal efficiency is observed to increase from 43% to 53% when the porous core regenerator is applied. Further, raising the compression ratio causes the peak pressure and thermal efficiency to increase, e.g., increasing the compression ratio from 13 to 15 causes the thermal efficiency and output work to increase from 53% to 55% and from 4.86 to 4.93 kJ, respectively. The regenerator can also be used as a catalytic converter for fine particles and some other emissions. The regenerator oxidizes unburned hydrocarbons. Meanwhile, heat recovered from the exhaust gases can reduce fuel consumption, further reducing pollutant emissions from the internal combustion engine.
Rod displacement measurements by x-ray CT and its impact on thermal-hydraulics in tight-lattice rod bundle (Joint research)

International Nuclear Information System (INIS)

Mitsutake, Toru; Misawa, Takeharu; Kureta, Masatoshi; Akimoto, Hajime

2005-06-01

In tight-lattice simulated rod bundles with about 1 mm gap between rods, a rod displacement might affect thermal-hydraulic characteristics since the displacement has a strong impact on the flow area change along the heated section. It should be important to estimate how large the rod position displacement could quantitatively affect critical power for the tight-lattice rod bundle from the point of improvement of prediction capability of subchannel analysis. In the present study, the inside-structure observation of the simulated seven-rod bundle of Reduced Moderation Water Reactor (RMWR) was made through the whole length of the test assembly. Based on the measured rod position data, the relation between the rod position displacement and the heat transfer characteristics was investigated experimentally and through the two kinds of subchannel analysis, the nominal rod position case and the measured rod position case, the effect on the predicted critical power was estimated. The high-energy X-ray computer tomograph (CT) of Fuels Monitoring Facilities (FMF) at the O-arai Engineering Center in Japan Nuclear Cycle Institute (JNC) was applied for the inside-structure observation of the test assembly. The CT view of the cross sections within the test assembly assured the hexagonal rod position arrangement was almost the same as expected by design. The measured data with the X-ray CT facility showed that all rod displacements were small, 0.5 millimeters at maximum and 0.2 millimeters in average. In the heat transfer experiments for the seven-rod bundle, the boiling transition (BT) position and the rod surface temperature behavior was measured. All thermocouples on the center rod downstream from the BT-onset axial height showed almost simultaneous temperature increase due to BT. And the thermocouples located on the same axial heights showed quite similar time-variation behaviors in the vapor cooling heat transfer regime. These results demonstrated the effect of the
Monitoring and optimization of thermal recovery wells at Nexen's Long Lake project

Energy Technology Data Exchange (ETDEWEB)

Furtado, S.; Howe, A.; Wozney, G.; Zaffar, S. [Nexen Inc. (Canada); Nelson, A. [Matrikon Inc. (Canada)

2011-07-01

The Long Lake project, operated by Nexen and situated in the Athabasca Oil Sands area in Alberta, Canada is a steam assisted gravity drainage scheme. In such thermal recovery processes, access to real time information is crucial. Nexen used specific tools to optimize monitoring in its Long Lake project and the aim of this paper is to present those customized well and facilities dashboards and reservoir trends. Real time and historical data on pressure, temperature injection and production rates are used in a Honeywell PHD Historian connected to a Delta-V DCS system to optimize recovery from the deposit. Results showed that these enhanced monitoring capabilities provided Nexen the ability to react rapidly to abnormal conditions, which resulted in significant financial benefits. The implementation of dashboard and reservoir trends in its Long Lake project helped Nexen to better monitor the reservoir and thus to optimize bitumen recovery.
Pumped Fluid Loop Heat Rejection and Recovery Systems for Thermal Control of the Mars Science Laboratory

Science.gov (United States)

Bhandari, Pradeep; Birur, Gajanana; Prina, Mauro; Ramirez, Brenda; Paris, Anthony; Novak, Keith; Pauken, Michael

2006-01-01

This viewgraph presentation reviews the heat rejection and heat recovery system for thermal control of the Mars Science Laboratory (MSL). The MSL mission will use mechanically pumped fluid loop based architecture for thermal control of the spacecraft and rover. The architecture is designed to harness waste heat from an Multi Mission Radioisotope Thermo-electric Generator (MMRTG) during Mars surface operations for thermal control during cold conditions and also reject heat during the cruise aspect of the mission. There are several test that are being conducted that will insure the safety of this concept. This architecture can be used during any future interplanetary missions utilizing radioisotope power systems for power generation.
Passive Smoking in a Displacement Ventilated Room

DEFF Research Database (Denmark)

Bjørn, Erik; Nielsen, Peter V.

The aim of this research is to see if the displacement ventilation principle can protect a person from exposure to passive tobacco smoking. This is done by full-scale experiments with two breathing thermal manikins, smoke visualisations, and tracer gas measurements. In some situations, exhaled...... smoke will stratify in a certain height due to the vertical temperature gradient. This horizontal layer of exhaled tobacco smoke may lead to exposure. In other situations, the smoke is mixed into the upper zone, and the passive smoker is protected to some extent by the displacement principle...
Impact of the operation of non-displaced feedwater heaters on the performance of Solar Aided Power Generation plants

International Nuclear Information System (INIS)

Qin, Jiyun; Hu, Eric; Nathan, Graham J.

2017-01-01

Highlights: • Impact of non-displaced feedwater heater on plant’s performance has been evaluated. • Two operation strategies for non-displaced feedwater heater has been proposed. • Constant temperature strategy is generally better. • Constant mass flow rate strategy is suit for rich solar thermal input. - Abstract: Solar Aided Power Generation is a technology in which low grade solar thermal energy is used to displace the high grade heat of the extraction steam in a regenerative Rankine cycle power plant for feedwater preheating purpose. The displaced extraction steam can then expand further in the steam turbine to generate power. In such a power plant, using the (concentrated) solar thermal energy to displace the extraction steam to high pressure/temperature feedwater heaters (i.e. displaced feedwater heaters) is the most popular arrangement. Namely the extraction steam to low pressure/temperature feedwater heaters (i.e. non-displaced feedwater heaters) is not displaced by the solar thermal energy. In a Solar Aided Power Generation plants, when solar radiation/input changes, the extraction steam to the displaced feedwater heaters requires to be adjusted according to the solar radiation. However, for the extraction steams to the non-displaced feedwater heaters, it can be either adjusted accordingly following so-called constant temperature strategy or unadjusted i.e. following so-called constant mass flow rate strategy, when solar radiation/input changes. The previous studies overlooked the operation of non-displaced feedwater heaters, which has also impact on the whole plant’s performance. This paper aims to understand/reveal the impact of the two different operation strategies for non-displaced feedwater heaters on the plant’s performance. In this paper, a 300 MW Rankine cycle power plant, in which the extraction steam to high pressure/temperature feedwater heaters is displaced by the solar thermal energy, is used as study case for this purpose. It
Development of a higher-order finite volume method for simulation of thermal oil recovery process using moving mesh strategy

Energy Technology Data Exchange (ETDEWEB)

Ahmadi, M. [Heriot Watt Univ., Edinburgh (United Kingdom)

2008-10-15

This paper described a project in which a higher order up-winding scheme was used to solve mass/energy conservation equations for simulating steam flood processes in an oil reservoir. Thermal recovery processes are among the most complex because they require a detailed accounting of thermal energy and chemical reaction kinetics. The numerical simulation of thermal recovery processes involves localized phenomena such as saturation and temperatures fronts due to hyperbolic features of governing conservation laws. A second order accurate FV method that was improved by a moving mesh strategy was used to adjust for moving coordinates on a finely gridded domain. The Finite volume method was used and the problem of steam injection was then tested using derived solution frameworks on both mixed and moving coordinates. The benefits of using a higher-order Godunov solver instead of lower-order ones were qualified. This second order correction resulted in better resolution on moving features. Preferences of higher-order solvers over lower-order ones in terms of shock capturing is under further investigation. It was concluded that although this simulation study was limited to steam flooding processes, the newly presented approach may be suitable to other enhanced oil recovery processes such as VAPEX, SAGD and in situ combustion processes. 23 refs., 28 figs.

Multiaxial Channeling Study of Disorder Accumulation and Recovery in Gold-Irradiated 6H-SiC

International Nuclear Information System (INIS)

Jiang, Weilin; Weber, William J.

2001-01-01

Single crystal 6H-SiC has been irradiated 60 degrees off normal with 2 MeV Au ions at 300 K to fluences of 0.029, 0.058 and 0.12 ions/nm, which produced relatively low damage levels. The disorder profiles as a function of ion fluence on both the Si and C sublattices have been determined simultaneously in situ using Rutherford backscattering and nuclear reaction analysis with 0.94 MeV D+ ions in channeling geometry along the , and axes. Along the axis at these low doses, similar levels of Si and C disorder are observed, and the damage accumulation is linear with dose. However, along and , the disorder accumulation is larger and increases sublinearly with dose. Furthermore, a higher level of C disorder than Si disorder is observed along the and axes, which is consistent with a smaller threshold displacement energy on the C sublattice in SiC. The mean lattice displacement, perpendicular to each corresponding axis, ranges from 0.014 to 0.037 nm for this range of ion fluences. A steady accumulation of small displacements due to lattice stress is observed along the axis, and a detectable reduction of the lattice stress perpendicular to the axis occurs at 0.12 Au/nm. There is only a moderate recovery of disorder, produced at and below 0.058 Au/nm, during thermal annealing at 570 K; more significant recovery is observed for 0.12 Au/nm along both the and axes
Oil/water displacement in microfluidic packed beds under weakly water-wetting conditions: competition between precursor film flow and piston-like displacement

Science.gov (United States)

Tanino, Yukie; Zacarias-Hernandez, Xanat; Christensen, Magali

2018-02-01

Optical microscopy was used to measure depth-averaged oil distribution in a quasi-monolayer of crushed marble packed in a microfluidic channel as it was displaced by water. By calibrating the transmitted light intensity to oil thickness, we account for depth variation in the fluid distribution. Experiments reveal that oil saturation at water breakthrough decreases with increasing Darcy velocity, U_{ {w}}, between capillary numbers {Ca} = μ _{ {w}} U_{ {w}}/σ = 9× 10^{-7} and 9× 10^{-6}, where μ _{ {w}} is the dynamic viscosity of water and σ is the oil/water interfacial tension, under the conditions considered presently. In contrast, end-point (long-time) remaining oil saturation depends only weakly on U_{ {w}}. This transient dependence on velocity is attributed to the competition between precursor film flow, which controls early time invasion dynamics but is inefficient at displacing oil, and piston-like displacement, which controls ultimate oil recovery. These results demonstrate that microfluidic experiments using translucent grains and fluids are a convenient tool for quantitative investigation of sub-resolution liquid/liquid displacement in porous media.
Pushing desalination recovery to the maximum limit: Membrane and thermal processes integration

KAUST Repository

Shahzad, Muhammad Wakil

2017-05-05

The economics of seawater desalination processes has been continuously improving as a result of desalination market expansion. Presently, reverse osmosis (RO) processes are leading in global desalination with 53% share followed by thermally driven technologies 33%, but in Gulf Cooperation Council (GCC) countries their shares are 42% and 56% respectively due to severe feed water quality. In RO processes, intake, pretreatment and brine disposal cost 25% of total desalination cost at 30–35% recovery. We proposed a tri-hybrid system to enhance overall recovery up to 81%. The conditioned brine leaving from RO processes supplied to proposed multi-evaporator adsorption cycle driven by low temperature industrial waste heat sources or solar energy. RO membrane simulation has been performed using WinFlow and IMSDesign commercial softwares developed by GE and Nitto. Detailed mathematical model of overall system is developed and simulation has been conducted in FORTRAN. The final brine reject concentration from tri-hybrid cycle can vary from 166,000ppm to 222,000ppm if RO retentate concentration varies from 45,000ppm to 60,000ppm. We also conducted economic analysis and showed that the proposed tri-hybrid cycle can achieve highest recovery, 81%, and lowest energy consumption, 1.76kWhelec/m3, for desalination reported in the literature up till now.
Measuring individual disaster recovery: a socioecological framework.

Science.gov (United States)

Abramson, David M; Stehling-Ariza, Tasha; Park, Yoon Soo; Walsh, Lauren; Culp, Derrin

2010-09-01

Disaster recovery is a complex phenomenon. Too often, recovery is measured in singular fashion, such as quantifying rebuilt infrastructure or lifelines, without taking in to account the affected population's individual and community recovery. A comprehensive framework is needed that encompasses a much broader and far-reaching construct with multiple underlying dimensions and numerous causal pathways; without the consideration of a comprehensive framework that investigates relationships between these factors, an accurate measurement of recovery may not be valid. This study proposes a model that encapsulates these ideas into a single framework, the Socio-Ecological Model of Recovery. Using confirmatory factor analysis, an operational measure of recovery was developed and validated using the five measures of housing stability, economic stability, physical health, mental health, and social role adaptation. The data were drawn from a sample of displaced households following Hurricane Katrina. Measures of psychological strength, risk, disaster exposure, neighborhood contextual effects, and formal and informal help were modeled to examine their direct and indirect effects on recovery using a structural equation model. All five elements of the recovery measure were positively correlated with a latent measure of recovery, although mental health and social role adaptation displayed the strongest associations. An individual's psychological strength had the greatest association with positive recovery, followed by having a household income greater than $20,000 and having informal social support. Those factors most strongly associated with an absence of recovery included the time displaced since the hurricane, being disabled, and living in a community with substantial social disorder. The socio-ecological framework provides a robust means for measuring recovery, and for testing those factors associated with the presence or absence of recovery.
Experimental and simulated displacement of oil in sand berea cores using aqueous solutions

International Nuclear Information System (INIS)

Ramirez, A.; Gonzalez, J.L.; Hernandez, F.; Hernandez, H.

2009-01-01

The development of a mathematical algorithm to simulate the displacement of a resident fluid using a displacing one in a saturated anisotropic porous media is shown in this work. The algorithm was included in the simulator developed by the present authors in previous works to represent the anisotropic distribution of the porous media properties and the fluid injection [Ramirez A et al. Mathematical simulation of oil reservoir properties. Chaos, solitons and Fractals 2008;38:778-88, Ramirez A et al. Simulation of uncompressible fluid flow through a porous media. Chaos, Solitons and Fractals 2009;39:1753-63] in a nested loop to analyze the participant nodes in the transport process and calculate the volumes of the resident and new fluids. The new routine developed takes in count the mobility of both fluids. Additionally experimental fluid displacement tests were done using heavy oil from Mexican reservoirs as a resident fluid in sand berea cores. The injection of new fluids in natural oil reservoirs is a part of the Enhanced oil recovery (EOR) methods used to improve the oil displacement and increase production after the primary stage of the oil recovery has been finished. Water is an available and economical resource to be used as a displacing fluid due to many of the producers (off-shores) of the oil industries are placed in the sea near the coast.
ON STABILITY OF THE OIL DISPLACEMENT FRONT UNDER CONDITIONS OF THERMOGAS IMPACT ON THE OIL BEARING LAYER

Directory of Open Access Journals (Sweden)

K. V. Dobrego

2016-01-01

Full Text Available The method of thermogas impact on the oil bearing layer is a perspective one to improve oil recovery. It is now under experimental implementation in Belarus. Stability of the thermal front and that of the oil displacement is a point of principle for the given technology. The article offers solution based on the method of small perturbations for the problem of the oil-displacement front stability under thermogas impact on the oil layer. The perturbation growth increment is shown to be quite different from that of the gas filtration combustion. Being determined by the perturbation wave number (or wave length, by difference in speed of the blowing filtration and that of the heat development front, by the ratios of densities, filtration coefficients, compressibility of the displacement agent and the displaced oil mass, and by other parameters. The author analyses the main parameters influencing the stability of the front. Recommendations are given on possible methods and procedures improving stability of the displacement front (neutralizing perturbation growth. The mechanisms of suppression or compensation of the front perturbation growth are as follows: the crude oil viscosity reduction and increase of that of the displacement agent, the displacement agent compressibility increase, increase of the thermogas impact heat-front width in the first instance at the expense of the temperature growth and alteration in the chemism (low temperature catalysts utilization, etc., reduction in speed of the front propagation and/or correspondingly of the displacement agent feed. Utilization of the gas or water-gas displacement agent as well as the agent impregnation with hydrophobic gases provides a relatively better stability of the front as compared to that employing water based compounds. Analytical data and derived recommendations are offered for utilization within the framework of general techniques and procedures of the thermogas impact process management
Coarse-grained simulation of molecular mechanisms of recovery in thermally activated shape-memory polymers

Science.gov (United States)

Abberton, Brendan C.; Liu, Wing Kam; Keten, Sinan

2013-12-01

Thermally actuated shape-memory polymers (SMPs) are capable of being programmed into a temporary shape and then recovering their permanent reference shape upon exposure to heat, which facilitates a phase transition that allows dramatic increase in molecular mobility. Experimental, analytical, and computational studies have established empirical relations of the thermomechanical behavior of SMPs that have been instrumental in device design. However, the underlying mechanisms of the recovery behavior and dependence on polymer microstructure remain to be fully understood for copolymer systems. This presents an opportunity for bottom-up studies through molecular modeling; however, the limited time-scales of atomistic simulations prohibit the study of key performance metrics pertaining to recovery. In order to elucidate the effects of phase fraction, recovery temperature, and deformation temperature on shape recovery, here we investigate the shape-memory behavior in a copolymer model with coarse-grained potentials using a two-phase molecular model that reproduces physical crosslinking. Our simulation protocol allows observation of upwards of 90% strain recovery in some cases, at time-scales that are on the order of the timescale of the relevant relaxation mechanism (stress relaxation in the unentangled soft-phase). Partial disintegration of the glassy phase during mechanical deformation is found to contribute to irrecoverable strain. Temperature dependence of the recovery indicates nearly full elastic recovery above the trigger temperature, which is near the glass-transition temperature of the rubbery switching matrix. We find that the trigger temperature is also directly correlated with the deformation temperature, indicating that deformation temperature influences the recovery temperatures required to obtain a given amount of shape recovery, until the plateau regions overlap above the transition region. Increasing the fraction of glassy phase results in higher strain
Control of waste well casing vent gas from a thermal enhanced oil recovery operation

International Nuclear Information System (INIS)

Peavy, M.A.; Braun, J.E.

1991-01-01

This paper presents an overview of a waste gas treatment system designed to control emissions from thermally enhanced oil recovery wells. This case study discusses the need, design, installation and operations of the system. Oryx Energy Company (Oryx) operates approximately 940 wells in the Midway-Sunset (MWSS) field under casing vapor recovery systems. The emissions collected from well casing vent gas cotaining hydrocarbons and hydrogen sulfide that are collected and processed through casing vapor recovery skids. These skids are composed of condensers, compressors, and pumps that separate fluids from the waste gas stream. The non-condensible gas is then disposed of in incinerators that reduce the hydrocarbon and sulfur emissions into the atmosphere. Approximately 91,000 lbs/day of hydrocarbon and 10,116 lbs/day of sulfur dioxide are removed from the atmosphere from wells contained within these systems operated by Oryx. These hydrocarbons yield approximately 550 barrels of oil per day (BOPD). The system helps manage the pressure differential from the reservoir into each wellbore and contributes to improved ambient air quality in Kern County, California
Experimental research on microscopic displacement mechanism of CO2-water alternative flooding in low permeability reservoir

Science.gov (United States)

Han, Hongyan; Zhu, Weiyao; Long, Yunqian; Song, Hongqing; Huang, Kun

2018-02-01

This paper provides an experimental method to deal with the problems of low oil recovery ratio faced with water flooding utilizing the CO2/water alternate displacement technology. A series of CO2/water alternate flooding experiments were carried out under 60°C and 18.4MPa using high temperature / pressure microscopic visualization simulation system. Then, we used the image processing technique and software to analyze the proportion of remaining oil in the displacement process. The results show that CO2 can extract the lighter chemical components in the crude oil and make it easier to form miscible phase, which can reduce the viscosity and favorable mobility ratio of oil. What’s more, the displacement reduces the impact of gas channeling, which can achieve an enlarged sweeping efficiency to improve filtration ability. In addition, the CO2 dissolved in oil and water can greatly reduce the interfacial tension, which can increase the oil displacement efficiency in a large extent. Generally speaking, the recovery rate of residual oil in the micro - model can be elevated up to 15.89% ∼ 16.48% under formation condition by alternate displacement.
Experimental study of solvent-based emulsion injection to enhance heavy oil recovery in Alaska North Slope area

Energy Technology Data Exchange (ETDEWEB)

Qiu, F.; Mamora, D. [Texas A and M Univ., College Station, TX (United States)

2010-07-01

This study examined the feasibility of using a chemical enhanced oil recovery method to overcome some of the technical challenges associated with thermal recovery in the Alaska North Slope (ANS). This paper described the second stage research of an experimental study on nano-particle and surfactant-stabilized solvent-based emulsions for the ANS area. Four successful core flood experiments were performed using heavy ANS oil. The runs included water flooding followed by emulsion flooding; and pure emulsion injection core flooding. The injection rate and core flooding temperature remained constant and only 1 PV micro-emulsion was injected after breakthrough under water flooding or emulsion flooding. Oil recovery increased by 26.4 percent from 56.2 percent original oil in place (OOIP) with waterflooding to 82.6 percent OOIP with injection of emulsion following water flooding. Oil recovery was slightly higher with pure emulsion flooding, at 85.8 percent OOIP. The study showed that low permeability generally resulted in a higher shear rate, which is favourable for in-situ emulsification and higher displacement efficiency. 11 refs., 4 tabs., 20 figs.
Influence of the thermal treatment on the stability of partially constrained recovery of NiTi actuator wire

International Nuclear Information System (INIS)

Mertmann, M.; Bracke, A.; Hornbogen, E.

1995-01-01

NiTi shape memory wire may be used for actuation purposes in flexible robotic grippers, which have to be able to handle objects of different size, shape or weight. Therefore it is advantageous to develop an electrically driven shape memory actuator, which may perform any combination of shape change and exerted force within the following limiting boundaries: - free recovery: gripping of a very small and lightweight object, - constrained recovery: gripping of an object with maximum size and weight. Several NiTi actuator wires are fabricated and annealed between 400 and 600 C after cold working in the martensitic state. After prestraining each wire is embedded in a silicone matrix material. The polymer works as a bias spring and is able to store elastic deformation energy. This paper investigates the influence of thermal treatment on the stability of the exerted force between the two boundaries of completely free and constrained recovery, the ''partially constrained recovery''. The stability of recovery strain and stress is measured in a test assembly, in which different modes of partially constrained recovery are simulated. The work is supplemented by dilatometric measurements carried out with each actuator wire before and after the test procedure. (orig.)
Minimizing temperature instability of heat recovery hot water system utilizing optimized thermal energy storage

Science.gov (United States)

Suamir, I. N.; Sukadana, I. B. P.; Arsana, M. E.

2018-01-01

One energy-saving technology that starts gaining attractive for hotel industry application in Indonesia is the utilization of waste heat of a central air conditioning system to heat water for domestic hot water supply system. Implementing the technology for such application at a hotel was found that hot water capacity generated from the heat recovery system could satisfy domestic hot water demand of the hotel. The gas boilers installed in order to back up the system have never been used. The hot water supply, however, was found to be instable with hot water supply temperature fluctuated ranging from 45 °C to 62 °C. The temperature fluctuations reaches 17 °C, which is considered instable and can reduce hot water usage comfort level. This research is aimed to optimize the thermal energy storage in order to minimize the temperature instability of heat recovery hot water supply system. The research is a case study approach based on cooling and hot water demands of a hotel in Jakarta-Indonesia that has applied water cooled chillers with heat recovery systems. The hotel operation with 329 guest rooms and 8 function rooms showed that hot water production in the heat recovery system completed with 5 m3 thermal energy storage (TES) could not hold the hot water supply temperature constantly. The variations of the cooling demand and hot water demands day by day were identified. It was found that there was significant mismatched of available time (hours) between cooling demand which is directly correlated to the hot water production from the heat recovery system and hot water usage. The available TES system could not store heat rejected from the condenser of the chiller during cooling demand peak time between 14.00 and 18.00 hours. The extra heat from the heat recovery system consequently increases the temperature of hot water up to 62 °C. It is about 12 K above 50 °C the requirement hot water temperature of the hotel. In contrast, the TES could not deliver proper
Multiaxial channeling study of disorder accumulation and recovery in gold-irradiated 6H-SiC

International Nuclear Information System (INIS)

Jiang, W.; Weber, W. J.

2001-01-01

Single crystal 6H-SiC has been irradiated 60 o off normal with 2 MeV Au 2+ ions at 300 K to fluences of 0.029, 0.058, and 0.12 ions/nm2, which produced relatively low damage levels. The disorder profiles as a function of ion fluence on both the Si and C sublattices have been determined simultaneously in situ using Rutherford backscattering and nuclear reaction analysis with 0.94 MeV D + ions in channeling geometry along the , , and axes. Along the axis at these low doses, similar levels of Si and C disorder are observed, and the damage accumulation is linear with dose. However, along and , the disorder accumulation is larger and increases sublinearly with dose. Furthermore, a higher level of C disorder than Si disorder is observed along the and axes, which is consistent with a smaller threshold displacement energy on the C sublattice in SiC. The mean lattice displacement, perpendicular to each corresponding axis, ranges from 0.014 to 0.037 nm for this range of ion fluences. A steady accumulation of small displacements due to lattice stress is observed along the axis, and a detectable reduction of the lattice stress perpendicular to the axis occurs at 0.12 Au 2+ /nm 2 . There is only a moderate recovery of disorder, produced at and below 0.058 Au 2+ /nm 2 , during thermal annealing at 570 K; more significant recovery is observed for 0.12 Au 2+ /nm 2 along both the and axes
Multiaxial Channeling Study of Disorder Accumulation and Recovery in Gold-Irradiated 6H-SiC

Energy Technology Data Exchange (ETDEWEB)

Jiang, Weilin; Weber, William J.

2001-09-14

Single crystal 6H-SiC has been irradiated 60 degrees off normal with 2 MeV Au ions at 300 K to fluences of 0.029, 0.058 and 0.12 ions/nm, which produced relatively low damage levels. The disorder profiles as a function of ion fluence on both the Si and C sublattices have been determined simultaneously in situ using Rutherford backscattering and nuclear reaction analysis with 0.94 MeV D+ ions in channeling geometry along the <0001>, <102> and <101> axes. Along the <0001> axis at these low doses, similar levels of Si and C disorder are observed, and the damage accumulation is linear with dose. However, along <102> and <101>, the disorder accumulation is larger and increases sublinearly with dose. Furthermore, a higher level of C disorder than Si disorder is observed along the <102> and <101> axes, which is consistent with a smaller threshold displacement energy on the C sublattice in SiC. The mean lattice displacement, perpendicular to each corresponding axis, ranges from 0.014 to 0.037 nm for this range of ion fluences. A steady accumulation of small displacements due to lattice stress is observed along the <101> axis, and a detectable reduction of the lattice stress perpendicular to the <0001> axis occurs at 0.12 Au/nm. There is only a moderate recovery of disorder, produced at and below 0.058 Au/nm, during thermal annealing at 570 K; more significant recovery is observed for 0.12 Au/nm along both the <0001> and <102> axes.
Acid rain recovery may help to mitigate the impacts of climate change on thermally sensitive fish in lakes across eastern North America.

Science.gov (United States)

Warren, Dana R; Kraft, Clifford E; Josephson, Daniel C; Driscoll, Charles T

2017-06-01

From the 1970s to 1990s, more stringent air quality regulations were implemented across North America and Europe to reduce chemical emissions that contribute to acid rain. Surface water pH slowly increased during the following decades, but biological recovery lagged behind chemical recovery. Fortunately, this situation is changing. In the past few years, northeastern US fish populations have begun to recover in lakes that were historically incapable of sustaining wild fish due to acidic conditions. As lake ecosystems across the eastern United States recover from acid deposition, the stress to the most susceptible populations of native coldwater fish appears to be shifting from acidification effects to thermal impacts associated with changing climate. Extreme summer temperature events - which are expected to occur with increasing frequency in the coming century - can stress and ultimately kill native coldwater fish in lakes where thermal stratification is absent or highly limited. Based on data from northeastern North America, we argue that recovery from acid deposition has the potential to improve the resilience of coldwater fish populations in some lakes to impacts of climate change. This will occur as the amount of dissolved organic carbon (DOC) in the water increases with increasing lake pH. Increased DOC will reduce water clarity and lead to shallower and more persistent lake thermoclines that can provide larger areas of coldwater thermal refuge habitat. Recovery from acidification will not eliminate the threat of climate change to coldwater fish, but secondary effects of acid recovery may improve the resistance of coldwater fish populations in lakes to the effects of elevated summer temperatures in historically acidified ecosystems. This analysis highlights the importance of considering the legacy of past ecosystem impacts and how recovery or persistence of those effects may interact with climate change impacts on biota in the coming decades. © 2016 John
Physical factors affecting the electrically assisted thermal bitumen recovery

Energy Technology Data Exchange (ETDEWEB)

Bogdanov, I.I.; Torres, J.-A.; Kamp, A.M. [CHLOE, University of Pau (France); Corre, B. [CSTJF, Total (France)

2011-07-01

In the heavy oil industry, thermal processes are used to enhance oil recovery by increasing the reservoir temperature which results in better oil mobility. Low frequency heating (LFH) is a technology using electrical conductivity of connate water to propagate current between electrodes, thus generating heat in the reservoir through the Joule effect. During the preheating and production periods, many physical factors may affect the LFH process and the aim of this study was to determine which factors affect the process and how, using a particular pattern of electrodes. Simulations were conducted using the CMG Stars reservoir simulator under different configurations, conditions and parameters. Important physical properties and operational conditions affecting the LFH process were determined and results showed that convection heat, bulk electrical conductivity and power distribution can be improved by salt water circulation. This paper highlighted the physical factors affecting LFH efficiency and these findings will be useful for future process design.
Analysis of displacement damage and defect production under cascade damage conditions

DEFF Research Database (Denmark)

Zinkle, S.J.; Singh, B.N.

1993-01-01

and residual defect production must be treated separately. An evaluation of experimental and computer defect production studies indicates that the overall fraction of defects surviving correlated annihilation in an energetic displacement cascade in copper decreases from about 30% of the Norgett......-Robinson-Torrens (NRT) calculated displacements at 4 K to about 10% of the NRT displacements at 300 K. Due to differences in the thermal stability of vacancy versus interstitial clusters, the fractions of freely migrating defects available for inducing microstructural changes at elevated temperatures may be higher...... for vacancies than for interstitials. The available evidence suggests that the fraction of freely migrating vacancies at temperatures relevant for void swelling in copper is greater than or similar to 5% of the calculated NRT displacements....
A Comparative Study for Modeling Displacement Instabilities due to TGO Formation in TBCs of High-Temperature Components in Nuclear Power Plant

Directory of Open Access Journals (Sweden)

Xia Huang

2016-01-01

Full Text Available This paper reports two numerical simulation methods for modeling displacement instabilities around a surface groove in a metal substrate used in nuclear power plant. The amplitude change in the groove, the downward displacement at the base node, and the groove displacement at the periphery were simulated using ABAQUS to compare the results from two methods, as well as the tangential stress in the elements at the groove base and periphery. The comparison showed that for the tangential stress two methods were in close agreement for all thermal cycles. For the amplitude change, the downward displacement, the groove displacement, and the stress distribution, the two methods were in close agreement for the first 3 to 6 thermal cycles. After that, inconsistency increased with the number of thermal cycles. It is interesting that the thermal cycle at which the discrepancy between the two methods began to occur corresponded to a thermally grown oxide (TGO thickness of 1 μm, which showed the accuracy of the present work over the classic method. It is concluded that the present work’s numerical simulation scheme worked better with a thinner TGO layer than the classic method and could overcome the limitation of TGO thickness by simulating any thickness.
Airflow and Contaminant Distribution in Hospital Wards with a Displacement Ventililation System

DEFF Research Database (Denmark)

Qian, H.; Nielsen, Peter Vilhelm; Li, Y.

2004-01-01

Airflow and Contaminant Distribution in Hospital Wards with a Displacement Ventilalation System. The 2nd International Conference on Build Environment and Public Health, BEPH 2004, Shenzhen , China . ABSTRACT Displacement ventilation has not been considered to be an applicable system for hospital...... to accurately predict three-dimensional distribution of air velocity, temperature, and contaminant concentration in the ward. Indoor airflow in a displacement ventilation system involves a combination of different flow streams such as the gravity currents and thermal plumes. It is important to choose...... ventilation system in hospital wards. It is for this purpose that we study the performance of displacement ventilation in hospital wards as one of the steps to optimize the ventilation design. When the prospect of applying displacement ventilation system in a hospital ward is examined, it should be necessary...
The effect of location of a convective heat source on displacement ventilation: CFD study

Energy Technology Data Exchange (ETDEWEB)

Park, H.J.; Holland, D. [Dunham Associates, Inc., Minneapolis, MN (United States). Advanced Technologies Group

2001-08-01

Two-dimensional computational simulations are performed to examine the effect of vertical location of a convective heat source on thermal displacement ventilation systems. In this study, a heat source is modeled with seven different heights from the floor (0.5, 0.75, 1.0, 1.25, 1.5, 1.75, 2.0 m) in a displacement ventilation environment. The flow and temperature fields in thermal displacement ventilation systems vary depending on the location of the heat source. As the heat source rises, the convective heat gain from the heat source to an occupied zone becomes less significant. This effect changes the temperature field and results in the reduction of the cooling load in the occupied zone. The stratification level is also affected by the heat source location at a given flow rate. (author)

Fast thermal annealing of implantation defects in silicon. Solid phase epitaxy and residual imperfection recovery

International Nuclear Information System (INIS)

Adekoya, O.A.

1987-06-01

Basic processes ruling the crystal reconstitution in solid phase during fast thermal annealing are studied; the role of electronic and thermodynamic effects at the interface is precised, following the implantations of a donor element (p + ), an acceptor element (B + ) and an intrinsic element (Ge + ). Then, after recrystallization, the electric role of residual point defects is shown together with the possibility of total recovery and an important electric activation of the doping [fr
Signal displacement in spiral-in acquisitions: simulations and implications for imaging in SFG regions.

Science.gov (United States)

Brewer, Kimberly D; Rioux, James A; Klassen, Martyn; Bowen, Chris V; Beyea, Steven D

2012-07-01

Susceptibility field gradients (SFGs) cause problems for functional magnetic resonance imaging (fMRI) in regions like the orbital frontal lobes, leading to signal loss and image artifacts (signal displacement and "pile-up"). Pulse sequences with spiral-in k-space trajectories are often used when acquiring fMRI in SFG regions such as inferior/medial temporal cortex because it is believed that they have improved signal recovery and decreased signal displacement properties. Previously postulated theories explain differing reasons why spiral-in appears to perform better than spiral-out; however it is clear that multiple mechanisms are occurring in parallel. This study explores differences in spiral-in and spiral-out images using human and phantom empirical data, as well as simulations consistent with the phantom model. Using image simulations, the displacement of signal was characterized using point spread functions (PSFs) and target maps, the latter of which are conceptually inverse PSFs describing which spatial locations contribute signal to a particular voxel. The magnitude of both PSFs and target maps was found to be identical for spiral-out and spiral-in acquisitions, with signal in target maps being displaced from distant regions in both cases. However, differences in the phase of the signal displacement patterns that consequently lead to changes in the intervoxel phase coherence were found to be a significant mechanism explaining differences between the spiral sequences. The results demonstrate that spiral-in trajectories do preserve more total signal in SFG regions than spiral-out; however, spiral-in does not in fact exhibit decreased signal displacement. Given that this signal can be displaced by significant distances, its recovery may not be preferable for all fMRI applications. Copyright © 2012 Elsevier Inc. All rights reserved.
Evaluating the climate benefits of CO2-enhanced oil recovery using life cycle analysis.

Science.gov (United States)

Cooney, Gregory; Littlefield, James; Marriott, Joe; Skone, Timothy J

2015-06-16

This study uses life cycle analysis (LCA) to evaluate the greenhouse gas (GHG) performance of carbon dioxide (CO2) enhanced oil recovery (EOR) systems. A detailed gate-to-gate LCA model of EOR was developed and incorporated into a cradle-to-grave boundary with a functional unit of 1 MJ of combusted gasoline. The cradle-to-grave model includes two sources of CO2: natural domes and anthropogenic (fossil power equipped with carbon capture). A critical parameter is the crude recovery ratio, which describes how much crude is recovered for a fixed amount of purchased CO2. When CO2 is sourced from a natural dome, increasing the crude recovery ratio decreases emissions, the opposite is true for anthropogenic CO2. When the CO2 is sourced from a power plant, the electricity coproduct is assumed to displace existing power. With anthropogenic CO2, increasing the crude recovery ratio reduces the amount of CO2 required, thereby reducing the amount of power displaced and the corresponding credit. Only the anthropogenic EOR cases result in emissions lower than conventionally produced crude. This is not specific to EOR, rather the fact that carbon-intensive electricity is being displaced with captured electricity, and the fuel produced from that system receives a credit for this displacement.
Multi-link laser interferometry architecture for interspacecraft displacement metrology

Science.gov (United States)

Francis, Samuel P.; Lam, Timothy T.-Y.; McClelland, David E.; Shaddock, Daniel A.

2018-03-01

Targeting a future Gravity Recovery and Climate Experiment (GRACE) mission, we present a new laser interferometry architecture that can be used to recover the displacement between two spacecraft from multiple interspacecraft measurements. We show it is possible to recover the displacement between the spacecraft centers of mass in post-processing by forming linear combinations of multiple, spatially offset, interspacecraft measurements. By canceling measurement error due to angular misalignment of the spacecraft, we remove the need for precise placement or alignment of the interferometer, potentially simplifying spacecraft integration. To realize this multi-link architecture, we propose an all-fiber interferometer, removing the need for any ultrastable optical components such as the GRACE Follow-On mission's triple mirror assembly. Using digitally enhanced heterodyne interferometry, the number of links is readily scalable, adding redundancy to our measurement. We present the concept, an example multi-link implementation and the signal processing required to recover the center of mass displacement from multiple link measurements. Finally, in a simulation, we analyze the limiting noise sources in a 9 link interferometer and ultimately show we can recover the 80 {nm}/√{ {Hz}} displacement sensitivity required by the GRACE Follow-On laser ranging interferometer.
Thermally-enhanced oil recovery method and apparatus

Science.gov (United States)

Stahl, Charles R.; Gibson, Michael A.; Knudsen, Christian W.

1987-01-01

A thermally-enhanced oil recovery method and apparatus for exploiting deep well reservoirs utilizes electric downhole steam generators to provide supplemental heat to generate high quality steam from hot pressurized water which is heated at the surface. A downhole electric heater placed within a well bore for local heating of the pressurized liquid water into steam is powered by electricity from the above-ground gas turbine-driven electric generators fueled by any clean fuel such as natural gas, distillate or some crude oils, or may come from the field being stimulated. Heat recovered from the turbine exhaust is used to provide the hot pressurized water. Electrical power may be cogenerated and sold to an electric utility to provide immediate cash flow and improved economics. During the cogeneration period (no electrical power to some or all of the downhole units), the oil field can continue to be stimulated by injecting hot pressurized water, which will flash into lower quality steam at reservoir conditions. The heater includes electrical heating elements supplied with three-phase alternating current or direct current. The injection fluid flows through the heater elements to generate high quality steam to exit at the bottom of the heater assembly into the reservoir. The injection tube is closed at the bottom and has radial orifices for expanding the injection fluid to reservoir pressure.
Experimental study on electromagnetic-assisted ZnO nanofluid flooding for enhanced oil recovery (EOR).

Science.gov (United States)

Adil, Muhammad; Lee, Keanchuan; Mohd Zaid, Hasnah; Ahmad Latiff, Noor Rasyada; Alnarabiji, Mohamad Sahban

2018-01-01

Recently, nano-EOR has emerged as a new frontier for improved and enhanced oil recovery (IOR & EOR). Despite their benefits, the nanoparticles tend to agglomerate at reservoir conditions which cause their detachment from the oil/water interface, and are consequently retained rather than transported through a porous medium. Dielectric nanoparticles including ZnO have been proposed to be a good replacement for EOR due to their high melting point and thermal properties. But more importantly, these particles can be polarized under electromagnetic (EM) irradiation, which provides an innovative smart Nano-EOR process denoted as EM-Assisted Nano-EOR. In this study, parameters involved in the oil recovery mechanism under EM waves, such as reducing mobility ratio, lowering interfacial tensions (IFT) and altering wettability were investigated. Two-phase displacement experiments were performed in sandpacks under the water-wet condition at 95°C, with permeability in the range of 265-300 mD. A crude oil from Tapis oil field was employed; while ZnO nanofluids of two different particle sizes (55.7 and 117.1 nm) were prepared using 0.1 wt. % nanoparticles that dispersed into brine (3 wt. % NaCl) along with SDBS as a dispersant. In each flooding scheme, three injection sequential scenarios have been conducted: (i) brine flooding as a secondary process, (ii) surfactant/nano/EM-assisted nano flooding, and (iii) second brine flooding to flush nanoparticles. Compare with surfactant flooding (2% original oil in place/OOIP) as tertiary recovery, nano flooding almost reaches 8.5-10.2% of OOIP. On the other hand, EM-assisted nano flooding provides an incremental oil recovery of approximately 9-10.4% of OOIP. By evaluating the contact angle and interfacial tension, it was established that the degree of IFT reduction plays a governing role in the oil displacement mechanism via nano-EOR, compare to mobility ratio. These results reveal a promising way to employ water-based ZnO nanofluid for
Experimental study on electromagnetic-assisted ZnO nanofluid flooding for enhanced oil recovery (EOR)

Science.gov (United States)

Ahmad Latiff, Noor Rasyada; Alnarabiji, Mohamad Sahban

2018-01-01

Recently, nano-EOR has emerged as a new frontier for improved and enhanced oil recovery (IOR & EOR). Despite their benefits, the nanoparticles tend to agglomerate at reservoir conditions which cause their detachment from the oil/water interface, and are consequently retained rather than transported through a porous medium. Dielectric nanoparticles including ZnO have been proposed to be a good replacement for EOR due to their high melting point and thermal properties. But more importantly, these particles can be polarized under electromagnetic (EM) irradiation, which provides an innovative smart Nano-EOR process denoted as EM-Assisted Nano-EOR. In this study, parameters involved in the oil recovery mechanism under EM waves, such as reducing mobility ratio, lowering interfacial tensions (IFT) and altering wettability were investigated. Two-phase displacement experiments were performed in sandpacks under the water-wet condition at 95°C, with permeability in the range of 265–300 mD. A crude oil from Tapis oil field was employed; while ZnO nanofluids of two different particle sizes (55.7 and 117.1 nm) were prepared using 0.1 wt. % nanoparticles that dispersed into brine (3 wt. % NaCl) along with SDBS as a dispersant. In each flooding scheme, three injection sequential scenarios have been conducted: (i) brine flooding as a secondary process, (ii) surfactant/nano/EM-assisted nano flooding, and (iii) second brine flooding to flush nanoparticles. Compare with surfactant flooding (2% original oil in place/OOIP) as tertiary recovery, nano flooding almost reaches 8.5–10.2% of OOIP. On the other hand, EM-assisted nano flooding provides an incremental oil recovery of approximately 9–10.4% of OOIP. By evaluating the contact angle and interfacial tension, it was established that the degree of IFT reduction plays a governing role in the oil displacement mechanism via nano-EOR, compare to mobility ratio. These results reveal a promising way to employ water-based ZnO nanofluid
Maximizing heavy-oil recovery by containing steam through optimized cementing

Energy Technology Data Exchange (ETDEWEB)

Ravi, K.; Hunter, B.; Kulakofsky, D [Halliburton Energy Services, Calgary, AB (Canada)

2008-10-15

As the world's oil and gas reserves decline, interest in unconventional sources, such as heavy oil, is increasing in response to global energy demand. Conventional methods are not sufficient to produce highly viscous heavy oil, and measures must be taken to decrease its viscosity. Although steam injection is an option, steam heats the casing and the cement sheath posing considerable thermal stress on the casing and the cement sheath. This paper described the design procedures that are required for evaluating the properties needed in the cement sheath in order to assist in withstanding thermal stresses. The steps needed to deliver an optimized cement system were presented. The paper presented an illustration of a typical wellbore for heavy-oil application and listed the parameters responsible for the extent of heat loss. These included formation properties; cement sheath thermal conductivity; steam-injection rate; and steam quality. The paper also described the Zhang unified mechanistic model which involved the temperature, pressure, steam quality, and heat loss changes as a function of the depth and the surroundings. Recommendations for withstanding well operations, hole cleaning, and slurry placement were also presented. Insurance for incomplete drilling fluid displacement and cement with the ability to react and respond were also proposed. It was concluded that in thermal recovery wells, energy loss to the surroundings could be reduced by lowering the thermal conductivity of the cement sheath. This could greatly improve the economics of such wells. 9 refs., 5 figs.
The recovery between 30K and 400K of copper and copper alloyed with gold after thermal-neutron irradiation

International Nuclear Information System (INIS)

Aspeling, J.C.

1977-08-01

The point defect reactions responsible for the recovery in resistivity between substages I(D) and I(E) in Stage I after thermal-neutron irradiation were investigated, using a new method termed the ideal isochronal method. Another substage was observed between I(D) and I(E). Whereas the peak temperatures of substages I(D) and I(E) are dependent on applied holding times in a well-known way, the main and very unusual characteristic of the new substage is that its peak temperature does not shift with a change in holding time. Using the ideal isochronal method, it was confirmed that substages I(D) and I(E) have a uniquely thermally activated energy. The new substage was attributed to a process whereby the interstitial has to overcome an energy barrier before recombining with a vacancy. In pure copper several recovery stages are observed between substage I(E) (about 52K) and Stage III (about 300K), whereas with the alloying of gold as a substitutional impurity, additional recovery stages are observed. In the alloyed copper a dose dependence contrary to that normally expected for interstitial-impurity reactions was observed. This phenomenon can, however, be explained consistently when the concentrations of interstitials, vacancies, impurities and impurity agglomerates are considered. No other free migrating point defect stage was observed between substage I(E) and Stage III. High-resolution measurements of the recovery stage at 225K, previously believed to shift in temperature with dose, showed that this stage actually consists of two stages and that the latter do not shift with dose. The two stages were explained in terms of close-pair recovery, in contrast to the previous explanation [af
The Long Term Recovery of New Orleans' Population after Hurricane Katrina.

Science.gov (United States)

Fussell, Elizabeth

2015-09-01

Hurricane Katrina created a catastrophe in the city of New Orleans when the storm surge caused the levee system to fail on August 29, 2005. The destruction of housing displaced hundreds of thousands of residents for varying lengths of time, often permanently. It also revealed gaps in our knowledge of how population is recovered after a disaster causes widespread destruction of urban infrastructure, housing and workplaces, and how mechanisms driving housing recovery often produce unequal social, spatial and temporal population recovery. In this article, I assemble social, spatial and temporal explanatory frameworks for housing and population recovery and then review research on mobility - both evacuation and migration - after Hurricane Katrina. The review reveals a need for a comprehensive social, spatial and temporal framework for explaining inequality in population recovery and displacement. It also shows how little is known about in-migrants and permanent out-migrants after a disaster.
Development of More Effective Biosurfactants for Enhanced Oil Recovery/Advanced Recovery Concepts Awards

Energy Technology Data Exchange (ETDEWEB)

McInerney, M.J.; Marsh, T.L.; Zhang, X.; Knapp, R.M.; Nagle, Jr., D.P.; Sharma, P.K.; Jackson, B.E.

2002-05-28

The objectives of this were two fold. First, core displacement studies were done to determine whether microbial processes could recover residual oil at elevated pressures. Second, the importance of biosurfactant production for the recovery of residual oil was studies. In these studies, a biosurfactant-producing, microorganisms called Bacillus licheniformis strain JF-2 was used. This bacterium produces a cyclic peptide biosurfactant that significantly reduces the interfacial tension between oil and brine (7). The use of a mutant deficient in surfactant production and a mathematical MEOR simulator were used to determine the major mechanisms of oil recovery by these two strains.
Technology of Inspection and Real-time Displacement Monitoring on Critical Pipe for Power Plant

Energy Technology Data Exchange (ETDEWEB)

Hyun, Jung Seob; Heo, Jae Sil [Korea Electric Power Research Institute, Daejeon (Korea, Republic of); Cho, Sun Young [KLES, Daejeon (Korea, Republic of); Heo, Jeong Yeol; Lee, Seong Kee [Korea South-East Power Co., Seoul (Korea, Republic of)

2009-10-15

High temperature steam pipes of thermal power plant are subject to a severe thermal range and usually operates well into the creep range. Cyclic operation of the plant subjects the piping system to mechanical and thermal fatigue damages. Also, poor or malfunctional supports can impose massive loads or stress onto the piping system. In order to prevent the serious damage and failure of the critical piping system, various inspection methods such as visual inspection, computational analysis and on-line piping displacement monitoring were developed. 3-dimensional piping displacement monitoring system was developed with using the aluminum alloy rod and rotary encoder sensors, this system was installed and operated on the high temperature steam piping of 'Y' thermal power plant successfully. It is expected that this study will contribute to the safety of piping system, which could minimize stress and extend the actual life of critical piping.
Practical considerations in developing numerical simulators for thermal recovery

Energy Technology Data Exchange (ETDEWEB)

Abou-Kassem, J.H. [Chemical and Petroleum Engineering Department, UAE University, Al-Ain (United Arab Emirates)

1996-08-15

Numerical simulation of steam injection and in-situ combustion-based oil recovery processes is of great importance in project design. Development of such numerical simulators is an on-going process, with improvements made as the process description becomes more complete, and also as better methods are devised to resolve certain numerical difficulties. This paper addresses some of the latter, and based on the author`s experience gives useful guidelines for developing more efficient numerical simulators of steam injection and in-situ combustion. The paper takes up a series of questions related to simulating thermal processes. Included are: the elimination of constraint equations at the matrix level, phase change, steam injection rate, alternative treatments of heat loss, relative permeabilities and importance of hysteresis effects, improved solutions to the grid orientation problem and other simulation problems such as potential inversion, grid block size, time-step size control and induced fractures. The points discussed in the paper should be of use to both simulator developers and users alike, and will lead to a better understanding of simulation results
Personal Exposure in Displacement Ventilated Rooms

DEFF Research Database (Denmark)

Brohus, Henrik; Nielsen, Peter Vilhelm

1996-01-01

in the lower part of the room close to the occupant. A personal exposure model for displacement ventilated rooms is proposed. The model takes the influence of gradients and the human thermal boundary layer into account. Two new quantities describing the interaction between a person and the ventilation......Personal exposure in a displacement ventilated room is examined. The stratified flow and the considerable concentration gradients necessitate an improvement of the widely used fully mixing compartmental approach. The exposure of a seated and a standing person in proportion to the stratification...... contaminant sources, this entrainment improves the indoor air quality. Measurements of exposure due to a passive contaminant source show a significant dependence on the flow field as well as on the contaminant source location. Poor system performance is found in the case of a passive contaminant released...
A spongy graphene based bimorph actuator with ultra-large displacement towards biomimetic application.

Science.gov (United States)

Hu, Ying; Lan, Tian; Wu, Guan; Zhu, Zicai; Chen, Wei

2014-11-07

Bimorph actuators, consisting of two layers with asymmetric expansion and generating bending displacement, have been widely researched. Their actuation performances greatly rely on the difference of coefficients of thermal expansion (CTE) between the two material layers. Here, by introducing a spongy graphene (sG) paper with a large negative CTE as well as high electrical-to-thermal properties, an electromechanical sG/PDMS bimorph actuator is designed and fabricated, showing an ultra-large bending displacement output under low voltage stimulation (curvature of about 1.2 cm(-1) at 10 V for 3 s), a high displacement-to-length ratio (∼0.79), and vibration motion at AC voltage (up to 10 Hz), which is much larger and faster than that of the other electromechanical bimorph actuators. Based on the sG/PDMS bimorph serving as the "finger", a mechanical gripper is constructed to realize the fast manipulation of the objects under 0.1 Hz square wave voltage stimulation (0-8 V). The designed bimorph actuator coupled with ultra-large bending displacement, low driven voltage, and the ease of fabrication may open up substantial possibilities for the utilization of electromechanical actuators in practical biomimetic device applications.
Investigation on Mechanisms of Polymer Enhanced Oil Recovery by Nuclear Magnetic Resonance and Microscopic Theoretical Analysis

International Nuclear Information System (INIS)

Ji-Cheng, Zhang; Kao-Ping, Song; Er-Long, Yang; Li, Liu

2008-01-01

Polymer flooding is an efficient technique to enhance oil recovery over water flooding. There are lots of discussions regarding the mechanisms for polymer flooding enhancing oil recovery. The main focus is whether polymer flooding can increase sweep efficiency alone, or can increase both of sweep efficiency and displacement efficiency. We present a study on this problem. Oil displacement experiments on 4 natural cores show that polymer flooding can increase oil recovery efficiency by more than 12% over water. Moreover, photos are taken by the nuclear magnetic resonance (NMR) method both after water flooding and after polymer flooding, which show remaining oil saturation distribution at the middle cross section and the central longitudinal section. Analyses of these photos demonstrate that polymer flooding can increase both sweep efficiency and displacement efficiency. (fundamental areas of phenomenology (including applications))
Study of Aquifer Thermal Energy Storage

Science.gov (United States)

Okuyama, Masaaki; Umemiya, Hiromichi; Shibuya, Ikuko; Haga, Eiji

Yamagata University 'Aquifer Thermal Energy Storage (ATES)' is the experimental system which has been running since 1982. From the results for along terms of experiments, we obtain many important knowledge. This paper presents the accomplishments for 16 years and the characteristics of thermal energy storage in thermal energy storage well. The conclusions show as follows. 1)In recent years, the thermal recovery factor of warm energy storage well becomes almost constant at about 60%. 2) The thermal recovery factor of cool energy storage well increases gradually and becomes at about 15%. 3) Since the ferric colloidal dam is formed in aquifer, thermal recovery factor increase year after year. 4) Back wash can remove clogging for ferric colloidal dam. 5) The apparent thermal diffusivity decrease gradually due to ferric colloidal dam.
The potential of permeability damage during thermal recovery of Cold Lake bitumen

Energy Technology Data Exchange (ETDEWEB)

Zhou, Z.; Wiwchar, B.; Gunter, W. D. [Alberta Research Council, Devon, AB (Canada); Dudley, J. S. [Imperial Oil Resources, Calgary, AB (Canada)

1999-09-01

Methods and results of coreflood tests designed to evaluate permeability damage caused by Clearwater formation clays in the Cold Lake area of Alberta are described. Three periods of permeability damage were encountered, the first during and shortly after the core was heated to 250 degrees C. Experimental evidence suggests that thermally activated grain crushing and subsequent fines migration were responsible for this initial permeability loss. The second period of damage was a gradual process which resulted in 65 per cent and 78 percent of permeability loss for the two corefloods, respectively. This phase of the permeability damage was considered to have been the result of hydrothermal reactions (berthierine to Fe-saponite). The third period of permeability damage occurred when fresh water was injected into the core. This was attributed to osmotic swelling of the Fe-saponite. A comparison of field evidence with experimental results revealed certain discrepancies, suspected to be due to the kinetics of the reaction, including disruption of berthierine grain coats and permeability damage due to subsequent fines migration. To err on the safe side, it is recommended that thermal recovery wells should be completed away from berthierine-rich zones. 15 refs., 2 tabs., 7 figs.
Development of More Effective Biosurfactants for Enhanced Oil Recovery/Advanced Recovery Concepts Awards; SEMIANNUAL

International Nuclear Information System (INIS)

McInerney, M.J.; Marsh, T.L.; Zhang, X.; Knapp, R.M.; Nagle, Jr. D.P.; Sharma, P.K.; Jackson, B.E.

2002-01-01

The objectives of this were two fold. First, core displacement studies were done to determine whether microbial processes could recover residual oil at elevated pressures. Second, the importance of biosurfactant production for the recovery of residual oil was studies. In these studies, a biosurfactant-producing, microorganisms called Bacillus licheniformis strain JF-2 was used. This bacterium produces a cyclic peptide biosurfactant that significantly reduces the interfacial tension between oil and brine (7). The use of a mutant deficient in surfactant production and a mathematical MEOR simulator were used to determine the major mechanisms of oil recovery by these two strains
Thermal recovery characteristics of Kori-unit 1 linde 80 weld

International Nuclear Information System (INIS)

Chi, S. H.; Hong, J. H.; Kuk, I. H.; Kim, I. S.

1997-01-01

The recovery activation energy, the order of reaction and the characteristic recovery rate constant were determined by isochronal (573K -823K) and isothermal (723K - 775K) annealing experiments on specimens made from a broken half of a Kori-Unit 1 surveillance weld specimen (fluence: 1.21 x 10 23 n/m 2 , E (1MeV, Cu: 0.29 wt%) to investigate the recovery characteristics of a high copper weld of neutron-irradiated reactor pressure vessel (RPV). Vickers microhardness tests were conducted to trace the recovery behavior after heat treatments. The results were analyzed in terms of recovery stages, behavior of responsible defects and recovery kinetics. It was shown that recovery occurred through two annealing stages (stage I: 673K - 753K, stage II: 753K - 823K) with recovery activation energies of 2.68 eV and 2.83 eV for stage I and II, respectively. The isothermal hardness recovery at 723 K and 775 K coincided with the ratio of the characteristic rate constant for each recovery stage. The order of reaction was 2 for both recovery stages. The recovery activation energies of present specimens are approximately equal to that of copper diffusion in α-iron in the presence of vacancies, suggesting that recovery may occur through the diffusion of copper atoms. The present results strongly support the copper precipitate coarsening model. (author)

Viscous fingering effects in solvent displacement of heavy oil

Energy Technology Data Exchange (ETDEWEB)

Cuthiell, D. [Suncor Energy, Fort McMurray, AB (Canada); Kissel, G.; Jackson, C.; Frauenfeld, T.W.J.; Fisher, D. [Alberta Research Council, Devon, AB (Canada); Rispler, K. [Saskatchewan Research Council, Saskatoon, SK (Canada)

2004-07-01

Vapour Extraction (VAPEX) is a solvent-based process that is analogous to steam-assisted gravity drainage (SAGD) for the recovery of heavy oil. A cyclic solvent process is preferred for thin reservoirs, particularly primary-depleted reservoirs. In a cyclic steam stimulation process, a solvent is injected into the reservoir for a period of time before oil is produced from the well. Viscous fingering is a phenomena that characterizes several solvent-based processes for the recovery of heavy oil. A combined experimental and simulation study was conducted to characterize viscous fingering under heavy oil recovery conditions (high ratio of oil to solvent viscosity). Four experiments were conducted in heavy oil-saturated sand packs. Three involved injection of a miscible, liquid solvent at the bottom of the sand pack. The heavy oil in these experiments was displaced upwardly. The fourth experiment involved top-down injection of a gaseous solvent. The miscible liquid displacement was dominated by one solvent finger which broke through to a producing well at the other end of the sand pack. Breakthrough times were similar to that at lower viscosity. The fourth experiment showed fingering along with features of a gravity-driven VAPEX process. Key features of the experiment and realistic fingering patterns were numerically simulated using a commercial reservoir simulator. It was emphasized that accurate modelling of dispersion is necessary in matching the observed phenomena. The simulations should include the capillary effects because of their significance for gaseous fingering and the VAPEX processes. 17 refs., 2 tabs., 20 figs.
Supporting technology for enhanced oil recovery: EOR thermal processes. Seventh Amendment and Extension to Annex 4, Enhanced oil recovery thermal processes

Energy Technology Data Exchange (ETDEWEB)

Reid, T B [USDOE Bartlesville Project Office, OK (United States); Colonomos, P [INTEVEP, Filial de Petroleos de Venezuela, SA, Caracas (Venezuela)

1993-02-01

This report contains the results of efforts under the six tasks of the Seventh Amendment and Extension of Annex IV, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Agreement. The report is presented in sections (for each of the 6 tasks) and each section contains one or more reports prepared by various individuals or groups describing the results of efforts under each of the tasks. A statement of each task, taken from the agreement, is presented on the first page of each section. The tasks are numbered 50 through 55. The first, second, third, fourth, fifth, sixth and seventh reports on Annex IV, Venezuela MEM/USA-DOE Fossil Energy Report IV-1, IV-2, IV-3, IV-4, IV-5 and IV-6 (DOE/BETC/SP-83/15, DOE/BC-84/6/SP, DOE/BC-86/2/SP, DOE/BC-87/2/SP, DOE/BC-89/l/SP, DOE/BC-90/l/SP, and DOE/BC-92/l/SP) contain the results for the first 49 tasks. Those reports are dated April 1983, August 1984, March 1986, July 1987, November 1988, December 1989, and October 1991, respectively. Each task report has been processed separately for inclusion in the Energy Science and Technology Database.
Boron isotopic enrichment by displacement chromatography

International Nuclear Information System (INIS)

Mohapatra, K.K.; Bose, Arun

2014-01-01

10 B enriched boron is used in applications requiring high volumetric neutron absorption (absorption cross section- 3837 barn for thermal and 1 barn for 1 MeV fast neutron). It is used in fast breeder reactor (as control rod material), in neutron counter, in Boron Neutron Capture Therapy etc. Owing to very small separation factor, boron isotopic enrichment is a complex process requiring large number of separation stages. Heavy Water Board has ventured in industrial scale production of 10 B enriched boron using Exchange Distillation Process as well as Ion Displacement Chromatography Process. Ion Displacement Chromatography process is used in Boron Enrichment Plant at HWP, Manuguru. It is based on isotopic exchange between borate ions (B(OH) 4 - ) on anion exchange resin and boric acid passing through resin. The isotopic exchange takes place due to difference in zero point energy of 10 B and 11 B
Sleeving-back of horizontal wells to control downstream oil saturation and improve oil recovery

Energy Technology Data Exchange (ETDEWEB)

Greaves, M.; Saghr, A. M. [Bath Univ (United Kingdom)

1998-12-31

Air injection has become popular as an enhanced recovery technology, applicable over a wide variety of reservoir conditions including heavy, medium and light oils. One problem observed in light oil reservoirs is the tendency to desaturate the oil layer downstream of the moving front. This is particularly common in the case of thermal recovery processes. In this experiment designed to study ways to restrict the de-saturation of the oil layer, a modified horizontal producer well, incorporating a `sleeve-back` principal was used. The objective was to replicate the `toe-to-heel` displacement process occurring during heavy oil recovery, wherein downstream oil is essentially immobile due to its high viscosity. The `sleeve-back` of the well was achieved using a co-aligned, two-well assembly, so that the upstream section of the horizontal producer well was active, and continuously adjusted during propagation of the combustion front. The use of this continuous `sleeve-back` operation to control the level of de-saturation in the downstream section of a sand pack was successful as confirmed by the very high oil recovery achieved, equivalent to 93.5 per cent of oil in place. The level of CO{sub 2} production was also very high. The `sleeve-back` of the horizontal producer well made the light oil in-situ combustion more efficient compared to what would be expected in a fully-open well. The `sleeve-back` of the well also produced thermal contours in the sand pack that closely resembled those observed with heavy, highly viscous oil. By sealing-off the otherwise open well in the downstream part of the reservoir, the de-saturation of the oil layer was prevented. 9 refs., 4 tabs., 9 figs.
Displaced Sense: Displacement, Religion and Sense-making

OpenAIRE

Naidu, Maheshvari

2016-01-01

Whether formally categorized as refugees or not, displaced migrants experience varying degrees of vulnerability in relation to where they find themselves displaced. The internally displaced furthermore squat invisibly and outside the boundaries of the legal framework and incentive structures accorded to those classified as 'refugee'. They are thus arguably, by and large, left to source sustaining solutions for themselves. This article works through the theoretical prism of sense-making theory...
Assessment of thermal efficiency of heat recovery coke making

Science.gov (United States)

Tiwari, H. P.; Saxena, V. K.; Haldar, S. K.; Sriramoju, S. K.

2017-08-01

The heat recovery stamp charge coke making process is quite complicated due to the evolved volatile matter during coking, is partially combusted in oven crown and sole flue in a controlled manner to provide heat for producing metallurgical coke. Therefore, the control and efficient utilization of heat in the oven crown, and sole flue is difficult, which directly affects the operational efficiency. Considering the complexity and importance of thermal efficiency, evolution of different gases, combustion of gasses in oven crown and sole flue, and heating process of coke oven has been studied. A nonlinear regression methodology was used to predict temperature profile of different depth of coal cake during the coking. It was observed that the predicted temperature profile is in good agreement with the actual temperature profile (R2 = 0.98) and is validated with the actual temperature profile of other ovens. A complete study is being done to calculate the material balance, heat balance, and heat losses. This gives an overall understanding of heat flow which affects the heat penetration into the coal cake. The study confirms that 60% heat was utilized during coking.
Performance and thermal decomposition analysis of foaming agent NPL-10 for use in heavy oil recovery by steam injection

Directory of Open Access Journals (Sweden)

Zhao Fa-Jun

2018-02-01

Full Text Available Foaming agents, despite holding potential in steam injection technology for heavy oil recovery, are still poorly investigated. In this work, we analyzed the performance of the foaming agent NPL-10 in terms of foam height and half-life under various conditions of temperature, pH, salinity, and oil content by orthogonal experiments. The best conditions of use for NPL-10 among those tested are T=220°C, pH 7, salinity 10000 mg·L–1 and oil content 10 g·L–1. Thermal decomposition of NPL-10 was also studied by thermogravimetric and differential thermal analyses. NPL-10 decomposes above 220°C, and decomposition is a two-step process. The kinetic triplet (activation energy, kinetic function and pre-exponential factor and the corresponding rate law were calculated for each step. Steps 1 and 2 follow kinetics of different order (n = 2 and ½, respectively. These findings provide some criteria for the selection of foaming agents for oil recovery by steam injection.
Multiaxial channeling study of disorder accumulation and recovery in gold-irradiated 6H-SiC

Energy Technology Data Exchange (ETDEWEB)

Jiang, W.; Weber, W. J.

2001-09-15

Single crystal 6H-SiC has been irradiated 60{sup o} off normal with 2 MeV Au{sup 2+} ions at 300 K to fluences of 0.029, 0.058, and 0.12 ions/nm2, which produced relatively low damage levels. The disorder profiles as a function of ion fluence on both the Si and C sublattices have been determined simultaneously in situ using Rutherford backscattering and nuclear reaction analysis with 0.94 MeV D{sup +} ions in channeling geometry along the <0001>, <1{bar 1}02>, and <10{bar 1}1> axes. Along the <0001> axis at these low doses, similar levels of Si and C disorder are observed, and the damage accumulation is linear with dose. However, along <1{bar 1}02> and <10{bar 1}1>, the disorder accumulation is larger and increases sublinearly with dose. Furthermore, a higher level of C disorder than Si disorder is observed along the <1{bar 1}02> and <10{bar 1}1> axes, which is consistent with a smaller threshold displacement energy on the C sublattice in SiC. The mean lattice displacement, perpendicular to each corresponding axis, ranges from 0.014 to 0.037 nm for this range of ion fluences. A steady accumulation of small displacements due to lattice stress is observed along the <10{bar 1}1> axis, and a detectable reduction of the lattice stress perpendicular to the <0001> axis occurs at 0.12 Au{sup 2+}/nm{sup 2}. There is only a moderate recovery of disorder, produced at and below 0.058 Au{sup 2+}/nm{sup 2}, during thermal annealing at 570 K; more significant recovery is observed for 0.12 Au{sup 2+}/nm{sup 2} along both the <0001> and <1{bar 1}02> axes.
A review of NOx formation mechanisms in recovery furnaces

International Nuclear Information System (INIS)

Nichols, K.M.; Thompson, L.M.; Empie, H.J.

1993-01-01

Review of NOx formation studies shows that NO forms in recovery furnaces primarily by two independent mechanisms, thermal and fuel. Thermal NO formation is extremely temperature-sensitive. However, theoretical predictions indicate that recovery furnace temperatures are not high enough to form significant thermal NO. Fuel NO formation is less temperature-sensitive, and is related to fuel nitrogen content. Black liquors are shown to contain 0.05 to 0.24 weight percent fuel nitrogen. Conversion of just 20% of this would yield approximately 25-120 ppm NOx (at 8% 0 2 ) in the flue gas, enough to represent the majority of the total NOx. Data from operating recovery furnaces show NOx emissions ranging from near zero to over 100 ppm at 8% 0 2 . An apparent increase in recovery furnace NOx emissions was observed with increasing solids. This increase is much less than predicted by thermal NO formation theory, indicating that other NO formation/destruction mechanisms, such as fuel NO formation, are important. No data are available to show the relative importance of thermal and fuel NO to total NOx during black liquor combustion
Hydro-Thermal Fatigue Resistance Measurements on Polymer Interfaces

Science.gov (United States)

Gurumurthy, Charan K.; Kramer, Edward J.; Hui, Chung-Yuen

1998-03-01

We have developed a new technique based on a fiber optic displacement sensor for rapid determination of hydro-thermal fatigue crack growth rate per cycle (da/dN) of an epoxy/polyimide interface used in flip chip attach microelectronic assembly. The sample is prepared as a trilayered cantilever beam by capillary flow of the epoxy underfill over a polyimide coated metallic beam. During hydro-thermal cycling the crack growth along the interface (from the free end) changes the displacement of this end of the beam and we measure the free end displacement at the lowest temperature in each hydro-thermal cycle. The change in beam displacement is then converted into crack growth rate (da/dN). da/dN depends on the maximum change in the strain energy release rate of the crack and the phase angle in each cycle. The relation between da/dN and maximum strain energy release rate characterizes the fatigue crack growth resistance of the interface. We have developed and used a simple model anhydride cured and a commercially available PMDA/ODA passivation for this study.
Reproductive Health Education and Services Needs of Internally Displaced Persons and Refugees following Disaster

Science.gov (United States)

Westhoff, Wayne W.; Lopez, Guillermo E.; Zapata, Lauren B.; Wilke Corvin, Jaime A.; Allen, Peter; McDermott, Robert J.

2008-01-01

Background: Following the occurrence of natural or man-made disaster, relief worker priorities include providing water, food, shelter, and immunizations for displaced persons. Like these essential initiatives, reproductive health education and services must also be incorporated into recovery efforts. Purpose: This study examined reproductive…
Comparison of microtweezers based on three lateral thermal actuator configurations

Science.gov (United States)

Luo, J. K.; Flewitt, A. J.; Spearing, S. M.; Fleck, N. A.; Milne, W. I.

2005-06-01

Thermal actuator-based microtweezers with three different driving configurations have been designed, fabricated and characterized. Finite element analysis has been used to model the device performance. It was found that one configuration of microtweezer, based on two lateral bimorph thermal actuators, has a small displacement (tip opening of the tweezers) and a very limited operating power range. An alternative configuration consisting of two horizontal hot bars with separated beams as the arms can deliver a larger displacement with a much-extended operating power range. This structure can withstand a higher temperature due to the wider beams used, and has flexible arms for increased displacement. Microtweezers driven by a number of chevron structures in parallel have similar maximum displacements but at a cost of higher power consumption. The measured temperature of the devices confirms that the device with the chevron structure can deliver the largest displacement for a given working temperature, while the bimorph thermal actuator design has the highest operating temperature at the same power due to its thin hot arm, and is prone to structural failure.
Calorimetric thermal-vacuum performance characterization of the BAe 80K space cryocooler

International Nuclear Information System (INIS)

Kotsubo, V.Y.; Johnson, D.L.; Ross, R.G. Jr.

1992-01-01

This paper on a comprehensive characterization program which is underway at JPL to generate test data on long-life, miniature Stirling-cycle cryocoolers for space application. The key focus of this paper is on the thermal performance of the British Aerospace (BAe) 80K split-Stirling-cycle cryocooler as measured in a unique calorimetric thermal-vacuum test chamber that accurately simulates the heat-transfer interfaces of space. Two separate cooling fluid loops provide precis individual control of the compressor and displacer heatsink temperatures. In addition, heatflow transducers enable calorimetric measurements of the heat rejected separately by the compressor and displacer. Cooler thermal performance has been mapped for coldtip temperatures ranging from below 45 K to above 150 K, for heat-sink temperatures ranging from 280 K to 320 K, and for a wide variety of operational variables including compressor-displacer phase, compressor-displacer stoke, drive frequency, and piston-displacer dc offset
The GDQ Method of Thermal Vibration Laminated Shell with Actuating Magnetostrictive Layers

Directory of Open Access Journals (Sweden)

C.C. Hong

2017-06-01

Full Text Available The research of laminated magnetostrictive shell under thermal vibration was computed by using the generalized differential quadrature (GDQ method. In the thermoelastic stress-strain equations that contain the terms linear temperature rise and the magnetostrictive material with velocity feedback control. The dynamic equilibrium differential equations with displacements were normalized and discretized into the dynamic discretized equations by the GDQ method. Two edges of laminated shell with clamped boundary conditions were considered. The values of interlaminar thermal stresses and center displacement of shell with and without velocity feedback control were calculated, respectively. The purpose of this research is to compute the time responses of displacement and stresses in the laminated magnetostrictive shell subjected to thermal vibration with suitable controlled gain values. The numerical GDQ results of displacement and stresses are also obtained and investigated. With velocity feedback and suitable control gain values are found to reduce the amplitude of displacement and stresses into a smaller value. The higher values of temperature get the higher amplitude of displacement and stresses. The GDQ results of actuating magnetostrictive shells can be applied in the field of morphing aircraft (adaptive structures and smart materials to reduce and suppress the vibration when under aero-thermal flutter.
Improved process for the injection of water for secondary recovery of petroleum

Energy Technology Data Exchange (ETDEWEB)

1967-07-24

In this process for the secondary recovery of petroleum from the formation, an aqueous displacing medium is injected through an injection well in communication with the formation. In this aqueous medium, a polymer is dissolved and the petroleum is thus displaced toward a producing well also in communication with the formation. The polymer is a liquid organic polymer, substantially linear, water-soluble, and having a resistance characteristic of at least 1.5. The polymer is dissolved in water in sufficient quantity such that the viscosity of the displacing medium is 0.5-15% of the viscosity of the crude oil to be displaced. The displacing medium is substantially free of molecular oxygen.
Study on properties and testing methods of thermo-responsive cementing system for well cementing in heavy oil thermal recovery

Science.gov (United States)

Li, Lianjiang

2017-08-01

In this paper, thermo-responsive cement slurry system were being developed, the properties of conventional cement slurry, compressive strength high temperature of cement sheath, mechanical properties of cement sheath and thermal properties of cement sheath were being tested. Results were being used and simulated by Well-Life Software, Thermo-responsive cement slurry system can meet the requirements of heavy oil thermal recovery production. Mechanical and thermal properties of thermo-responsive cement sheath were being tested. Tensile fracture energy of the thermo-responsive cement sheath is larger than conventional cement. The heat absorption capacity of conventional cement sheath is larger than that of thermo-responsive cement sheath, this means more heat is needed for the unit mass once increasing 1.0 °C, which also indicates that thermo-responsive cement own good heat insulating and preservation effects. The heat conductivity coefficient and thermal expansion coefficient of thermo-responsive cement is less than and conventional cement, this means that thermo-responsive cement have good heat preservation and insulation effects with good thermal expansion stabilities.
Waste Heat Recovery and Recycling in Thermal Separation Processes: Distillation, Multi-Effect Evaporation (MEE) and Crystallization Processes

Energy Technology Data Exchange (ETDEWEB)

Emmanuel A. Dada; Chandrakant B. Panchal; Luke K. Achenie; Aaron Reichl; Chris C. Thomas

2012-12-03

Evaporation and crystallization are key thermal separation processes for concentrating and purifying inorganic and organic products with energy consumption over 1,000 trillion Btu/yr. This project focused on a challenging task of recovering low-temperature latent heat that can have a paradigm shift in the way thermal process units will be designed and operated to achieve high-energy efficiency and significantly reduce the carbon footprint as well as water footprint. Moreover, this project has evaluated the technical merits of waste-heat powered thermal heat pumps for recovery of latent heat from distillation, multi-effect evaporation (MEE), and crystallization processes and recycling into the process. The Project Team has estimated the potential energy, economics and environmental benefits with the focus on reduction in CO2 emissions that can be realized by 2020, assuming successful development and commercialization of the technology being developed. Specifically, with aggressive industry-wide applications of heat recovery and recycling with absorption heat pumps, energy savings of about 26.7 trillion Btu/yr have been estimated for distillation process. The direct environmental benefits of this project are the reduced emissions of combustible products. The estimated major reduction in environmental pollutants in the distillation processes is in CO2 emission equivalent to 3.5 billion lbs/year. Energy consumption associated with water supply and treatments can vary between 1,900 kWh and 23,700 kWh per million-gallon water depending on sources of natural waters [US DOE, 2006]. Successful implementation of this technology would significantly reduce the demand for cooling-tower waters, and thereby the use and discharge of water treatment chemicals. The Project Team has also identified and characterized working fluid pairs for the moderate-temperature heat pump. For an MEE process, the two promising fluids are LiNO3+KNO3+NANO3 (53:28:19 ) and LiNO3+KNO3+NANO2
The potential of permeability damage during the thermal recovery of the Cold Lake bitumen

Energy Technology Data Exchange (ETDEWEB)

Zhou, Z.; Wiwchar, B.; Gunter, W. D. [Alberta Research Council, Devon, AB (Canada); Dudley, J. S. [Imperial Oil Ltd., Sarnia, ON (Canada). Research Dept.

1997-08-01

It has been suggested that hydrothermal reactions of clay minerals, present in all oil sands deposits in the Clearwater Formation at Cold Lake, may cause permeability damage during thermal recovery. To gain an idea of the extent of the damage, two corefloods were conducted at 250 degrees C. The first period of permeability damage occurred during and shortly after the core was heated to 250 degrees C, the second period was a gradual process , but resulted in 65 per cent and 78 per cent respectively, whereas the third period occurred when fresh water was injected into the core. These periods of damage were attributed to thermally activated grain crushing and fines migration, hydrothermal reactions, and osmotic swelling of the hydrothermal clay, respectively. Laboratory results do not agree with field experiments, although there is some field evidence for the disruption of berthierine (a form of clay) grain coats and permeability damage due to subsequent fines migration. In view of this evidence it was suggested that injection wells should not be placed in berthierine-rich zone. 15 refs., 2 tabs., 7 figs.
Thermal Error Test and Intelligent Modeling Research on the Spindle of High Speed CNC Machine Tools

Science.gov (United States)

Luo, Zhonghui; Peng, Bin; Xiao, Qijun; Bai, Lu

2018-03-01

Thermal error is the main factor affecting the accuracy of precision machining. Through experiments, this paper studies the thermal error test and intelligent modeling for the spindle of vertical high speed CNC machine tools in respect of current research focuses on thermal error of machine tool. Several testing devices for thermal error are designed, of which 7 temperature sensors are used to measure the temperature of machine tool spindle system and 2 displacement sensors are used to detect the thermal error displacement. A thermal error compensation model, which has a good ability in inversion prediction, is established by applying the principal component analysis technology, optimizing the temperature measuring points, extracting the characteristic values closely associated with the thermal error displacement, and using the artificial neural network technology.
A review of concentrated photovoltaic-thermal (CPVT) hybrid solar systems with waste heat recovery (WHR)

Institute of Scientific and Technical Information of China (English)

Xing Ju; Chao Xu; Zhirong Liao; Xiaoze Du; Gaosheng Wei; Zhifeng Wang; Yongping Yang

2017-01-01

In conventional photovoltaic (PV) systems,a large portion of solar energy is dissipated as waste heat since the generating efficiency is usually less than 30％.As the dissipated heat can be recovered for various applications,the wasted heat recovery concentrator PV/thermal (WHR CPVT) hybrid systems have been developed.They can provide both electricity and usable heat by combining thermal systems with concentrator PV (CPV) module,which dramatically improves the overall conversion efficiency of solar energy.This paper systematically and comprehensively reviews the research and development ofWHR CPVT systems.WHR CPVT systems with innovative design configurations,different theoretical evaluation models and experimental test processes for several implementations are presented in an integrated manner.We aim to provide a global point of view on the research trends,market potential,technical obstacles,and the future work which is required in the development of WHR CPVT technology.Possibly,it will offer a generic guide to the investigators who are interested in the study of WHR CPVT systems.

First-order character of the displacive structural transition in BaWO4

International Nuclear Information System (INIS)

Tan Da-Yong; Xiao Wan-Sheng; Zhou Wei; Chen Ming; Xiong Xiao-Lin; Song Mao-Shuang

2012-01-01

Nearly all displacive transitions have been considered to be continuous or second order, and the rigid unit mode (RUM) provides a natural candidate for the soft mode. However, in-situ X-ray diffraction and Raman measurements show clearly the first-order evidences for the scheelite-to-fergusonite displacive transition in BaWO 4 : a 1.6% volume collapse, coexistence of phases, and hysteresis on release of pressure. Such first-order signatures are found to be the same as the soft modes in BaWO 4 , which indicates the scheelite-to-fergusonite displacive phase transition hides a deeper physical mechanism. By the refinement of atomic displacement parameters, we further show that the first-order character of this phase transition stems from a coupling of large compression of soft BaO 8 polyhedrons to the small displacive distortion of rigid WO 4 tetrahedrons. Such a coupling will lead to a deeper physical insight in the phase transition of the common scheelite-structured compounds. (condensed matter: structural, mechanical, and thermal properties)
THERMAL CONSOLIDATION OF LAYERED POROUS HALF-SPACE TO VARIABLE THERMAL LOADING

Institute of Scientific and Technical Information of China (English)

BAI Bing

2006-01-01

An analytical method was derived for the thermal consolidation of layered,saturated porous half-space to variable thermal loading with time. In the coupled governing equations of linear thermoelastic media, the influences of thermo-osmosis effect and thermal filtration effect were introduced. Solutions in Laplace transform space were first obtained and then numerically inverted. The responses of a double-layered porous space subjected to exponential decaying thermal loading were studied. The influences of the differences between the properties of the two layers (e.g., the coefficient of thermal consolidation, elastic modulus) on thermal consolidation were discussed. The studies show that the coupling effects of displacement and stress fields on temperature field can be completely neglected, however, thc thermo-osmosis effect has an obvious influence on thermal responses.
Combined Simulation of a Micro Permanent Magnetic Linear Contactless Displacement Sensor

Directory of Open Access Journals (Sweden)

Jing Gao

2010-09-01

Full Text Available The permanent magnetic linear contactless displacement (PLCD sensor is a new type of displacement sensor operating on the magnetic inductive principle. It has many excellent properties and has already been used for many applications. In this article a Micro-PLCD sensor which can be used for microelectromechanical system (MEMS measurements is designed and simulated with the CST EM STUDIO® software, including building a virtual model, magnetostatic calculations, low frequency calculations, steady current calculations and thermal calculations. The influence of some important parameters such as air gap dimension, working frequency, coil current and eddy currents etc. is studied in depth.
Simulation of petroleum recovery in naturally fractured reservoirs: physical process representation

Energy Technology Data Exchange (ETDEWEB)

Paiva, Hernani P.; Miranda Filho, Daniel N. de [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil); Schiozer, Denis J. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil)

2012-07-01

The naturally fractured reservoir recovery normally involves risk especially in intermediate to oil wet systems because of the simulations poor efficiency results under waterflood displacement. Double-porosity models are generally used in fractured reservoir simulation and have been implemented in the major commercial reservoir simulators. The physical processes acting in petroleum recovery are represented in double-porosity models by matrix-fracture transfer functions, therefore commercial simulators have their own implementations, and as a result different kinetics and final recoveries are attained. In this work, a double porosity simulator was built with Kazemi et al. (1976), Sabathier et al. (1998) and Lu et al. (2008) transfer function implementations and their recovery results have been compared using waterflood displacement in oil-wet or intermediate-wet systems. The results of transfer function comparisons have showed recovery improvements in oil-wet or intermediate-wet systems under different physical processes combination, particularly in fully discontinuous porous medium when concurrent imbibition takes place, coherent with Firoozabadi (2000) experimental results. Furthermore, the implemented transfer functions, related to a double-porosity model, have been compared to double-porosity commercial simulator model, as well a discrete fracture model with refined grid, showing differences between them. Waterflood can be an effective recovery method even in fully discontinuous media for oil-wet or intermediate-wet systems where concurrent imbibition takes place with high enough pressure gradients across the matrix blocks. (author)
APPLICATIONS OF THERMAL ENERGY STORAGE TO WASTE HEAT RECOVERY IN THE FOOD PROCESSING INDUSTRY, Final Report

Energy Technology Data Exchange (ETDEWEB)

Lundberg, W. L.; Christenson, James A.

1979-07-31

A project is discussed in which the possibilities for economical waste heat recovery and utilization in the food industry were examined. Waste heat availability and applications surveys were performed at two manufacturing plants engaged in low temperature (freezing) and high temperature (cooking, sterilizing, etc.) food processing. The surveys indicate usable waste heat is available in significant quantities which could be applied to existing, on-site energy demands resulting in sizable reductions in factory fuel and energy usage. At the high temperature plant, the energy demands involve the heating of fresh water for boiler make-up, for the food processes and for the daily clean-up operation. Clean-up poses an opportunity for thermal energy storage since waste heat is produced during the one or two production shifts of each working day while the major clean-up effort does not occur until food production ends. At the frozen food facility, the clean-up water application again exists and, in addition, refrigeration waste heat could also be applied to warm the soil beneath the ground floor freezer space. Systems to recover and apply waste heat in these situations were developed conceptually and thermal/economic performance predictions were obtained. The results of those studies indicate the economics of waste heat recovery can be attractive for facilities with high energy demand levels. Small factories, however, with relatively low energy demands may find the economics marginal although, percentagewise, the fuel and energy savings are appreciable.
Supporting technology for enhanced oil recovery for thermal processes

Energy Technology Data Exchange (ETDEWEB)

Reid, T.B.; Bolivar, J.

1997-12-01

This report contains the results of efforts under the six tasks of the Ninth Amendment and Extension of Annex IV, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Agreement. The report is presented in sections (for each of the 6 tasks) and each section contains one or more reports prepared by various individuals or groups describing the results of efforts under each of the tasks. A statement of each task, taken from the agreement, is presented on the first page of each section. The tasks are numbered 62 through 67. The first, second, third, fourth fifth, sixth, seventh, eighth, and ninth reports on Annex IV, [Venezuela MEM/USA-DOE Fossil Energy Report IV-1, IV-2, IV-3, IV-4, IV-5, IV-6, IV-7, and IV-8 (DOE/BETC/SP-83/15, DOE/BC-84/6/SP, DOE/BC-86/2/SP, DOE/BC-87/2/SP, DOE/BC-90/1/SP, DOE/BC-90/1/SP) (DOE/BC-92/1/SP, DOE/BC-93/3/SP, and DOE/BC-95/3/SP)] contain the results from the first 61 tasks. Those reports are dated April 1983, August 1984, March 1986, July 1987, November 1988, October 1991, February 1993, and March 1995 respectively.
Recovery in dc and rf performance of off-state step-stressed AlGaN/GaN high electron mobility transistors with thermal annealing

International Nuclear Information System (INIS)

Kim, Byung-Jae; Hwang, Ya-Hsi; Ahn, Shihyun; Zhu, Weidi; Dong, Chen; Lu, Liu; Ren, Fan; Holzworth, M. R.; Jones, Kevin S.; Pearton, Stephen J.; Smith, David J.; Kim, Jihyun; Zhang, Ming-Lan

2015-01-01

The recovery effects of thermal annealing on dc and rf performance of off-state step-stressed AlGaN/GaN high electron mobility transistors were investigated. After stress, reverse gate leakage current and sub-threshold swing increased and drain current on-off ratio decreased. However, these degradations were completely recovered after thermal annealing at 450 °C for 10 mins for devices stressed either once or twice. The trap densities, which were estimated by temperature-dependent drain-current sub-threshold swing measurements, increased after off-state step-stress and were reduced after subsequent thermal annealing. In addition, the small signal rf characteristics of stressed devices were completely recovered after thermal annealing
Displacement Parameter Inversion for a Novel Electromagnetic Underground Displacement Sensor

Directory of Open Access Journals (Sweden)

Nanying Shentu

2014-05-01

Full Text Available Underground displacement monitoring is an effective method to explore deep into rock and soil masses for execution of subsurface displacement measurements. It is not only an important means of geological hazards prediction and forecasting, but also a forefront, hot and sophisticated subject in current geological disaster monitoring. In previous research, the authors had designed a novel electromagnetic underground horizontal displacement sensor (called the H-type sensor by combining basic electromagnetic induction principles with modern sensing techniques and established a mutual voltage measurement theoretical model called the Equation-based Equivalent Loop Approach (EELA. Based on that work, this paper presents an underground displacement inversion approach named “EELA forward modeling-approximate inversion method”. Combining the EELA forward simulation approach with the approximate optimization inversion theory, it can deduce the underground horizontal displacement through parameter inversion of the H-type sensor. Comprehensive and comparative studies have been conducted between the experimentally measured and theoretically inversed values of horizontal displacement under counterpart conditions. The results show when the measured horizontal displacements are in the 0–100 mm range, the horizontal displacement inversion discrepancy is generally tested to be less than 3 mm under varied tilt angles and initial axial distances conditions, which indicates that our proposed parameter inversion method can predict underground horizontal displacement measurements effectively and robustly for the H-type sensor and the technique is applicable for practical geo-engineering applications.
Study on Dynamic Characteristics of Microbial Enhanced Oil Recovery

Science.gov (United States)

Zhao, Yang; Shi, Fang; Qin, Wuying; Yan, Jing

2018-01-01

With the rapid development of economy, the demand for oil is increasing day by day. MEOR has the advantages of low cost and no pollution to the environment, attracted widespread attention. In this paper, the dynamic characteristics of microbial enhanced oil recovery were studied by laboratory experiments. The result showed that all the microbial flooding recovery rate could reach more than 5%, and the total recovery could reach more than 35% and if the injection period of microbial composite system was advanced, the whole oil displacement process could be shortened and the workload would be reduced.
Surface displacements and pillar stresses associated with nuclear waste disposal in salt

International Nuclear Information System (INIS)

Hardy, M.P.; St John, C.M.

1977-01-01

A numerical model for regional analysis of stresses and displacement, resulting from heat generating waste placement in underground salt excavations, is presented. The model, which is an extension of that described by McClain and Starfield (1971), is based upon the displacement discontinuity method of stress analysis. It incorporates an empirical characterization of creep behavior of material on the excavation horizon and accounts for thermally induced stresses and displacements. The versatility of this approach is illustrated by the results of three relatively short simulations of test scale disposal facilities at shallow and greater depths. In addition, a three-dimensional code was used to evaluate the surface displacement history for a full-scale repository. This latter code, a thermoelastic analysis, gives an upper bound for the surface movements. It is concluded that the pillar stresses are the result of a complex non-linear interaction of many variables, and the maximum pillar stress can reach several multiples of the tributory-area pillar stress
Adaptive implicit method for thermal compositional reservoir simulation

Energy Technology Data Exchange (ETDEWEB)

Agarwal, A.; Tchelepi, H.A. [Society of Petroleum Engineers, Richardson, TX (United States)]|[Stanford Univ., Palo Alto (United States)

2008-10-15

As the global demand for oil increases, thermal enhanced oil recovery techniques are becoming increasingly important. Numerical reservoir simulation of thermal methods such as steam assisted gravity drainage (SAGD) is complex and requires a solution of nonlinear mass and energy conservation equations on a fine reservoir grid. The most currently used technique for solving these equations is the fully IMplicit (FIM) method which is unconditionally stable, allowing for large timesteps in simulation. However, it is computationally expensive. On the other hand, the method known as IMplicit pressure explicit saturations, temperature and compositions (IMPEST) is computationally inexpensive, but it is only conditionally stable and restricts the timestep size. To improve the balance between the timestep size and computational cost, the thermal adaptive IMplicit (TAIM) method uses stability criteria and a switching algorithm, where some simulation variables such as pressure, saturations, temperature, compositions are treated implicitly while others are treated with explicit schemes. This presentation described ongoing research on TAIM with particular reference to thermal displacement processes such as the stability criteria that dictate the maximum allowed timestep size for simulation based on the von Neumann linear stability analysis method; the switching algorithm that adapts labeling of reservoir variables as implicit or explicit as a function of space and time; and, complex physical behaviors such as heat and fluid convection, thermal conduction and compressibility. Key numerical results obtained by enhancing Stanford's General Purpose Research Simulator (GPRS) were also presented along with a list of research challenges. 14 refs., 2 tabs., 11 figs., 1 appendix.
Enhanced Recovery in Tight Gas Reservoirs using Maxwell-Stefan Equations

Science.gov (United States)

Santiago, C. J. S.; Kantzas, A.

2017-12-01

Due to the steep production decline in unconventional gas reservoirs, enhanced recovery (ER) methods are receiving great attention from the industry. Wet gas or liquid rich reservoirs are the preferred ER candidates due to higher added value from natural gas liquids (NGL) production. ER in these reservoirs has the potential to add reserves by improving desorption and displacement of hydrocarbons through the medium. Nevertheless, analysis of gas transport at length scales of tight reservoirs is complicated because concomitant mechanisms are in place as pressure declines. In addition to viscous and Knudsen diffusion, multicomponent gas modeling includes competitive adsorption and molecular diffusion effects. Most models developed to address these mechanisms involve single component or binary mixtures. In this study, ER by gas injection is investigated in multicomponent (C1, C2, C3 and C4+, CO2 and N2) wet gas reservoirs. The competing effects of Knudsen and molecular diffusion are incorporated by using Maxwell-Stefan equations and the Dusty-Gas approach. This model was selected due to its superior properties on representing the physics of multicomponent gas flow, as demonstrated during the presented model validation. Sensitivity studies to evaluate adsorption, reservoir permeability and gas type effects are performed. The importance of competitive adsorption on production and displacement times is demonstrated. In the absence of adsorption, chromatographic separation is negligible. Production is merely dictated by competing effects between molecular and Knudsen diffusion. Displacement fronts travel rapidly across the medium. When adsorption effects are included, molecules with lower affinity to the adsorption sites will be produced faster. If the injected gas is inert (N2), an increase in heavier fraction composition occurs in the medium. During injection of adsorbing gases (CH4 and CO2), competitive adsorption effects will contribute to improved recovery of heavier
Drop and recovery of thermal conductivity of AlN upon UV irradiation

International Nuclear Information System (INIS)

AlShaikhi, A; Srivastava, G P

2007-01-01

We have performed calculations of the room-temperature thermal conductivity of oxygen contaminated aluminium nitride (AlN) by employing the Callaway model with a detailed account of three-phonon scattering processes. The role of Al vacancy and O substitution of N has been examined in the form of extended defects (clusters) and point defects. Our work provides support for the theoretical model proposed by Harris et al. [Phys. Rev. B. 47, 5428 (1993)] to explain the experimentally observed drop in the conductivity upon UV irradiation and its recovery upon UV removal and subsequent illumination of the sample with visible light at room temperature. With the reported oxygen concentration in the sample, the scattering of phonons from oxygen-related extended defects is found to be ineffective. Within the picture presented by Harris et al., the point impurity scattering parameter increases by around 17% upon UV irradiation of the sample at room temperature
Déplacements polyphasiques en milieu poreux. Injection de vapeur en conditions adiabatiques Multiphase Displacements in Porous Media. Steam Flooding under Adiabatic Conditions

Directory of Open Access Journals (Sweden)

Koci X.

2006-11-01

Full Text Available Dans un article antérieur [1], un dispositif expérimental permettant l'étude en milieu poreux des déplacements par fluides chauds, en conditions isothermes, a été présenté, ainsi que les résultats obtenus. Ce mode d'écoulement, qui ne fait pas intervenir A previous paper [1] described an experimental device designed for the study of multiphase displacements by hot fluids in porous media under isothermal conditions together with the results obtained. This type of flow, which does not take into account the progress of temperature fronts, is not representative of what actually happens in the field when a thermal enhanced oil recovery method is applied. In fact in this case, flows may be considered as quasiadiabatic. To gain a better understanding of the phenomena induced by such adiabatic displacements, new equipment was designed to reproduce conditions close to those in the field. Various experiments were modeled with a simulator developed at Institut Français du Pétrole (IFP, using results obtained under isothermal conditions (for instance, relative permeability curves. There is good agreement between experiments and computation. These experimental results were then compared to those obtained under isothermal conditions. Some hypotheses are put forward to explain the differences observed between the two types of flows. Experiments were carried out in unconsolidated cores made of packed sand. This sand mainly consisted of silica (over 99 weight %. Grain size was between 60 and 100 microns; the corresponding permeability was about 4. 10 to the power of (-12 m². The fluids consisted of distilled water and Albelf C-68 oil. New equipment was designed because of problems related to heat losses. For slow displacement rates at high temperatures, a small heat loss results in a decrease in temperature and therefore in steam condensation. Use of nonmetallic parts for the core-holder strongly reduces heat losses radially and longitudinally so
Uncovering Recovery: The Resistible Rise of Recovery and Resilience

Directory of Open Access Journals (Sweden)

David Harper

2012-10-01

recognition,” founded on a model of identity politics which displaces and marginalizes the need for social, political and economic redistribution to address many of the underlying causes of emotional distress. We conclude by stating that it is only when the collective, structural experiences of inequality and injustice are explicitly linked to processes of emotional distress that recovery will be possible.
Finding New Thermoelectric Compounds Using Crystallographic Data: Atomic Displacement Parameters

International Nuclear Information System (INIS)

Chakoumakos, B.C.; Mandrus, D.G.; Sales, B.C.; Sharp, J.W.

1999-01-01

A new structure-property relationship is discussed which links atomic displacement parameters (ADPs) and the lattice thermal conductivity of clathrate-like compounds. For many clathrate-like compounds, in which one of the atom types is weakly bound and ''rattles'' within its atomic cage, room temperature ADP information can be used to estimate the room temperature lattice thermal conductivity, the vibration frequency of the ''rattler'', and the temperature dependence of the heat capacity. Neutron data and X-ray crystallography data, reported in the literature, are used to apply this analysis to several promising classes of thermoelectric materials
Recovery of heavy metals from intractable wastes: A thermal approach

Energy Technology Data Exchange (ETDEWEB)

Kirk, D.W. [Univ. of Toronto (Canada)

1996-12-31

The generation of industrial solid wastes containing leachable species of environmental concern is a problem for developing and developed nations alike. These materials arise from direct processing of mineral ores, from production of metals and minerals, from manufacturing operations, and from air and water pollution treatment processes. The general characteristics that make these wastes intractable is that their content of hazardous species is not easily liberated from the waste yet is not bound so tightly that they are safe for landfill disposal or industrial use. The approach taken in this work is a thermal treatment that separates the inorganic contaminants from the wastes. The objective is to provide recovery and reuse of both the residual solids and liberated contaminants. The results from operating this technique using two very different types of waste are described. The reasons that the process will work for a wide variety of wastes are explored. By using the knowledge of the thermodynamic stability of the phases found from the characterization analyses, a thermal regime was found that allowed separation of the contaminants without capturing the matrix materials. Bench scale studies were carried out using a tube furnace. Samples of the wastes were heated in crucible boats from 750 to 1150{degrees}C in the presence of various chlorinating agents. The offgas contained 90{sup +}% of the targeted contaminants despite their complex matrix form. The residue was free of contamination. As a result of the efficient concentrating mechanism of the process, the contaminants in the offgas solids are attractive for reuse in metallurgical industries. As an additional benefit, the organic contaminants of the residues were eliminated. Dioxin traces in the solids before treatment were absent after treatment. 15 refs., 4 figs., 4 tabs.
Lamé Parameter Estimation from Static Displacement Field Measurements in the Framework of Nonlinear Inverse Problems

DEFF Research Database (Denmark)

Hubmer, Simon; Sherina, Ekaterina; Neubauer, Andreas

2018-01-01

. The main result of this paper is the verification of a nonlinearity condition in an infinite dimensional Hilbert space context. This condition guarantees convergence of iterative regularization methods. Furthermore, numerical examples for recovery of the Lam´e parameters from displacement data simulating......We consider a problem of quantitative static elastography, the estimation of the Lam´e parameters from internal displacement field data. This problem is formulated as a nonlinear operator equation. To solve this equation, we investigate the Landweber iteration both analytically and numerically...... a static elastography experiment are presented....
Method for limiting movement of a thermal shield for a nuclear reactor, and thermal shield displacement limiter therefor

International Nuclear Information System (INIS)

Meuschke, R.E.; Boyd, C.H.

1989-01-01

This patent describes a method of limiting the movement of a thermal shield of a nuclear reactor. It comprises: machining at least four (4) pockets in upper portions of a thermal shield circumferentially about a core barrel of a nuclear reactor to receive key-wave inserts; tapping bolt holes in the pockets of the thermal shield to receive bolts; positioning key-wave inserts into the pockets of the thermal shield to be bolted in place with the bolt holes; machining dowel holes at least partially through the positioned key-way inserts and the thermal shield to receive dowel pins; positioning dowel pins in the dowel holes in the key-way insert and thermal shield to tangentially restrain movement of the thermal shield relative to the core barrel; sliding limiter keys into the key-way inserts and bolting the limiter keys to the core barrel to tangentially restrain movement of the thermal shield relative and the core barrel while allowing radial and axial movement of the thermal shield relative to the core barrel; machining dowel holes through the limiter key and at least partially through the core barrel to receive dowel pins; positioning dowel pins in the dowel holes in the limiter key and core barrel to restrain tangential movement of the thermal shield relative to the core barrel of the nuclear reactor
National Institute for Petroleum and Energy Research 1989 annual report

Energy Technology Data Exchange (ETDEWEB)

1990-11-01

Research programs on reservoir rocks petroleum, and enhanced recovery are briefly presented. Topics include: Geotechnology; reservoir assessment and characterization; TORIS Research Support; three phase relative permeability; static pore structure analysis of reservoir rocks; effects of pore structure on oil/contaminants ganglia distribution; development of improved microbial flooding methods; development of improved surfactant flooding systems; development of improved alkaline flooding methods; development of improved mobility-control methods; gas miscible displacement; development of improved immiscible gas displacement methodology; thermal processes for light oil recovery; thermal processes for heavy oil recovery; an application of natural isotopes in groundwater for solving environmental problems; processing and thermodynamics research; thermochemistry and thermophysical properties of organic nitrogen- and diheteroatom-containing compounds; in situ hydrogenation; and fuel chemistry.

Displacement ventilation

DEFF Research Database (Denmark)

Kosonen, Risto; Melikov, Arsen Krikor; Mundt, Elisabeth

The aim of this Guidebook is to give the state-of-the art knowledge of the displacement ventilation technology, and to simplify and improve the practical design procedure. The Guidebook discusses methods of total volume ventilation by mixing ventilation and displacement ventilation and it gives...... insights of the performance of the displacement ventilation. It also shows practical case studies in some typical applications and the latest research findings to create good local micro-climatic conditions....
Wireless Displacement Sensing of Micromachined Spiral-Coil Actuator Using Resonant Frequency Tracking

Directory of Open Access Journals (Sweden)

Mohamed Sultan Mohamed Ali

2014-07-01

Full Text Available This paper reports a method that enables real-time displacement monitoring and control of micromachined resonant-type actuators using wireless radiofrequency (RF. The method is applied to an out-of-plane, spiral-coil microactuator based on shape-memory-alloy (SMA. The SMA spiral coil forms an inductor-capacitor resonant circuit that is excited using external RF magnetic fields to thermally actuate the coil. The actuation causes a shift in the circuit’s resonance as the coil is displaced vertically, which is wirelessly monitored through an external antenna to track the displacements. Controlled actuation and displacement monitoring using the developed method is demonstrated with the microfabricated device. The device exhibits a frequency sensitivity to displacement of 10 kHz/µm or more for a full out-of-plane travel range of 466 µm and an average actuation velocity of up to 155 µm/s. The method described permits the actuator to have a self-sensing function that is passively operated, thereby eliminating the need for separate sensors and batteries on the device, thus realizing precise control while attaining a high level of miniaturization in the device.
Application of laser speckle displacement analysis to clinical dentistry

Science.gov (United States)

Cumberpatch, G. K. D.; Hood, J. A. A.

1997-03-01

Success of dental restorations is dependent on the integrity of the tooth/restoration interface. Distortion of teeth due to operative procedures has previously been measured using LVDT's and strain-gauges and has provided useful but limited information. This paper reports on the verification of a system for laser speckle photography and its use to quantitative distortions in teeth from matrix band application and the use of bonded composite resin restorations. Tightening of matrix bands around teeth results in an inward deformation of the cusps, increasing incrementally as the band is tightened. Deflections of 50 micrometer/cusp were recorded. A delayed recovery was noted consistent with the viscoelastic behavior of dentine. For bonded restorations recovery will place the adhesion interface in a state of tension when the band is released and may cause premature failure. Premolar teeth restored with bonded resin restorations exhibited inward displacement of cusps of 12 - 15 micrometer. Deformation was not within the buccal-lingual axis as suggested by prior studies. Molar teeth bonded with composite resin restoration exhibit complex and variable cusp displacement in both magnitude (0 - 30 micrometer) and direction. Complete and partial debonding could be detected. Interproximal cusp bending could be quantitated and lifting of the restoration from the cavity floor was detectable. Deformations evidenced indicate the tooth/restoration interface is in a stressed state and this may subsequently lead to failure. The technique has the potential to aid in development of restoration techniques that minimize residual stress.
Dispersal of Exhaled Air and Personal Exposure in Displacement Ventilated Rooms

DEFF Research Database (Denmark)

Bjørn, Erik; Nielsen, Peter Vilhelm

2002-01-01

The influence of the human exhalation on flow fields, contaminant distributions, and personal exposures in displacement ventilated rooms is studied together with the effects of physical movement. Experiments are conducted in full-scale test rooms with life-sized breathing thermal manikins....... Numerical simulations support the experiments. Air exhaled through the mouth can lock in a thermally stratified layer, if the vertical temperature gradient in breathing zone height is sufficiently large. With exhalation through the nose, exhaled air flows to the upper part of the room. The exhalation flow...
The Effect of Fuel Mass Fraction on the Combustion and Fluid Flow in a Sulfur Recovery Unit Thermal Reactor

Directory of Open Access Journals (Sweden)

Chun-Lang Yeh

2016-11-01

Full Text Available Sulfur recovery unit (SRU thermal reactors are negatively affected by high temperature operation. In this paper, the effect of the fuel mass fraction on the combustion and fluid flow in a SRU thermal reactor is investigated numerically. Practical operating conditions for a petrochemical corporation in Taiwan are used as the design conditions for the discussion. The simulation results show that the present design condition is a fuel-rich (or air-lean condition and gives acceptable sulfur recovery, hydrogen sulfide (H2S destruction, sulfur dioxide (SO2 emissions and thermal reactor temperature for an oxygen-normal operation. However, for an oxygen-rich operation, the local maximum temperature exceeds the suggested maximum service temperature, although the average temperature is acceptable. The high temperature region must be inspected very carefully during the annual maintenance period if there are oxygen-rich operations. If the fuel mass fraction to the zone ahead of the choke ring (zone 1 is 0.0625 or 0.125, the average temperature in the zone behind the choke ring (zone 2 is higher than the zone 1 average temperature, which can damage the downstream heat exchanger tubes. If the zone 1 fuel mass fraction is reduced to ensure a lower zone 1 temperature, the temperature in zone 2 and the heat exchanger section must be monitored closely and the zone 2 wall and heat exchanger tubes must be inspected very carefully during the annual maintenance period. To determine a suitable fuel mass fraction for operation, a detailed numerical simulation should be performed first to find the stoichiometric fuel mass fraction which produces the most complete combustion and the highest temperature. This stoichiometric fuel mass fraction should be avoided because the high temperature could damage the zone 1 corner or the choke ring. A higher fuel mass fraction (i.e., fuel-rich or air-lean condition is more suitable because it can avoid deteriorations of both zone 1
Compliant electro-thermal microactuators

DEFF Research Database (Denmark)

Jonsmann, Jacques; Sigmund, Ole; Bouwstra, Siebe

1999-01-01

This paper describes design, microfabrication and characterisation of topology optimised compliant electro-thermal microactuators. The actuators are fabricated by a fast prototyping process using laser micromachining and electroplating. Actuators are characterised with respect to displacement...
Investigation on thermal environment improvement by waste heat recovery in the underground station in Qingdao metro

Science.gov (United States)

Liu, Jianwei; Liu, Jiaquan; Wang, Fengyin; Wang, Cuiping

2018-03-01

The thermal environment parameters, like the temperature and air velocity, are measured to investigate the heat comfort status of metro staff working area in winter in Qingdao. The temperature is affected obviously by the piston wind from the train and waiting hall in the lower Hall, and the temperature is not satisfied with the least heat comfort temperature of 16 °C. At the same time, the heat produced by the electrical and control equipments is brought by the cooling air to atmosphere for the equipment safety. Utilizing the water-circulating heat pump, it is feasible to transfer the emission heat to the staff working area to improve the thermal environment. Analyzed the feasibility from the technique and economy when using the heat pump, the water-circulating heat pump could be the best way to realize the waste heat recovery and to help the heat comfort of staff working area in winter in the underground metro station in north China.
Gas-assisted gravity drainage (GAGD) process for improved oil recovery

Science.gov (United States)

Rao, Dandina N [Baton Rouge, LA

2012-07-10

A rapid and inexpensive process for increasing the amount of hydrocarbons (e.g., oil) produced and the rate of production from subterranean hydrocarbon-bearing reservoirs by displacing oil downwards within the oil reservoir and into an oil recovery apparatus is disclosed. The process is referred to as "gas-assisted gravity drainage" and comprises the steps of placing one or more horizontal producer wells near the bottom of a payzone (i.e., rock in which oil and gas are found in exploitable quantities) of a subterranean hydrocarbon-bearing reservoir and injecting a fluid displacer (e.g., CO.sub.2) through one or more vertical wells or horizontal wells. Pre-existing vertical wells may be used to inject the fluid displacer into the reservoir. As the fluid displacer is injected into the top portion of the reservoir, it forms a gas zone, which displaces oil and water downward towards the horizontal producer well(s).
Diagnosis and on-line displacement monitoring for critical pipe of fossil power plant

Energy Technology Data Exchange (ETDEWEB)

Heo, J. S.; Hyun, J. S. [Korea Electric Power Corporation, Seoul (Korea, Republic of); Heo, J. R.; Lee, S. K.; Cho, S. Y. [Korea South-East Power Co., Ltd., Seoul (Korea, Republic of)

2009-07-01

High temperature steam pipes of fossil power plant are subject to a severe thermal range and usually operates well into the creep range. Cyclic operation of the plant subjects the piping system to mechanical and thermal fatigue mechanisms and poor or malfunctional support assemblies can impose massive loads or stress onto the piping system. In order to prevent the serious damage and failure of the critical pipe system, various inspection methods such as visual inspection, computational analysis and on-line piping displacement monitoring were developed. 3-Dimensional piping displacement monitoring system was developed with using he aluminum alloy rod and rotary encoder type sensors, this system was installed and operated on the 'Y' fossil power plant successfully. It is expected that this study will contribute to the safety of piping system, which could minimize stress and extend the actual life of critical piping.
Primary shield displacement and bowing

International Nuclear Information System (INIS)

Scott, K.V.

1978-01-01

The reactor primary shield is constructed of high density concrete and surrounds the reactor core. The inlet, outlet and side primary shields were constructed in-place using 2.54 cm (1 in) thick steel plates as the forms. The plates remained as an integral part of the shields. The elongation of the pressure tubes due to thermal expansion and pressurization is not moving through the inlet nozzle hardware as designed but is accommodated by outward displacement and bowing of the inlet and outlet shields. Excessive distortion of the shields may result in gas seal failures, intolerable helium gas leaks, increased argon-41 emissions, and shield cooling tube failures. The shield surveillance and testing results are presented
Energy implications of the thermal recovery of biodegradable municipal waste materials in the United Kingdom

International Nuclear Information System (INIS)

Burnley, Stephen; Phillips, Rhiannon; Coleman, Terry; Rampling, Terence

2011-01-01

Highlights: → Energy balances were calculated for the thermal treatment of biodegradable wastes. → For wood and RDF, combustion in dedicated facilities was the best option. → For paper, garden and food wastes and mixed waste incineration was the best option. → For low moisture paper, gasification provided the optimum solution. - Abstract: Waste management policies and legislation in many developed countries call for a reduction in the quantity of biodegradable waste landfilled. Anaerobic digestion, combustion and gasification are options for managing biodegradable waste while generating renewable energy. However, very little research has been carried to establish the overall energy balance of the collection, preparation and energy recovery processes for different types of wastes. Without this information, it is impossible to determine the optimum method for managing a particular waste to recover renewable energy. In this study, energy balances were carried out for the thermal processing of food waste, garden waste, wood, waste paper and the non-recyclable fraction of municipal waste. For all of these wastes, combustion in dedicated facilities or incineration with the municipal waste stream was the most energy-advantageous option. However, we identified a lack of reliable information on the energy consumed in collecting individual wastes and preparing the wastes for thermal processing. There was also little reliable information on the performance and efficiency of anaerobic digestion and gasification facilities for waste.
Effects of local fatigue on myoelectrical activity of erector spine muscles and the center for pressure displacement of the feet during balance recovery following postural perturbation in kyphotic subjects

Directory of Open Access Journals (Sweden)

Rooholah Rezaee

2014-07-01

Full Text Available Background: kyphosis deformity affects postural control. Muscular fatigue is one of the factors that can impair the mechanism of body balance. The aim of this study was to determine the effects of local fatigue on the myoelectrical activity of erector spine muscles and the center for pressure displacement of the feet during balance recovery following postural perturbation in kyphotic subjects. Methods: In this quasi-experimental study, 12 male students with>40 degrees thoracic kyphosis and 12 controls were selected to participate in the study. A flexible ruler was used to measure thoracic kyphosis. For postural control assessment, each subject underwent unexpected, forward-backward perturbations while standing on a foot scan mounted on a movable plate triggered by a weight equivalent to 10% of the subjects’ body weight. Experimental procedure was measured before (3 trails and after (3 trials the fatigue protocol. The myoelectric activity of the erector spine and multi fidus was compared in the groups using repeated measures of ANOVA and independent t-test (P<0.05. Results: There was no significant difference in the foot center of pressure displacement in both groups after muscular fatigue. After fatigue, there was an increase in the activity of longissimus thoracis (P=0.001 and iliocostalis thoracis (P= 0.001 in control group, while no significant difference was reported for the muscular activity of multifidus (p=0.084. The activity of langisimus thoracis was significantly increased (P=0.028 in kyphtic group after fatigue. Conclusion: erector spine muscles fatigue could not significantly affect the postural control in both groups, but the electrical activity of erector spine muscles during balance recovery following postural perturbation in kyphotic subjects was different than the controls.
Nonclassical thermal-state superpositions: Analytical evolution law and decoherence behavior

Science.gov (United States)

Meng, Xiang-guo; Goan, Hsi-Sheng; Wang, Ji-suo; Zhang, Ran

2018-03-01

Employing the integration technique within normal products of bosonic operators, we present normal product representations of thermal-state superpositions and investigate their nonclassical features, such as quadrature squeezing, sub-Poissonian distribution, and partial negativity of the Wigner function. We also analytically and numerically investigate their evolution law and decoherence characteristics in an amplitude-decay model via the variations of the probability distributions and the negative volumes of Wigner functions in phase space. The results indicate that the evolution formulas of two thermal component states for amplitude decay can be viewed as the same integral form as a displaced thermal state ρ(V , d) , but governed by the combined action of photon loss and thermal noise. In addition, the larger values of the displacement d and noise V lead to faster decoherence for thermal-state superpositions.
Job Displacement and Crime

DEFF Research Database (Denmark)

Bennett, Patrick; Ouazad, Amine

We use a detailed employer-employee data set matched with detailed crime information (timing of crime, fines, convictions, crime type) to estimate the impact of job loss on an individual's probability to commit crime. We focus on job losses due to displacement, i.e. job losses in firms losing...... a substantial share of their workers, for workers with at least three years of tenure. Displaced workers are more likely to commit offenses leading to conviction (probation, prison terms) for property crimes and for alcohol-related traffic violations in the two years following displacement. We find no evidence...... that displaced workers' propensity to commit crime is higher than non-displaced workers before the displacement event; but it is significantly higher afterwards. Displacement impacts crime over and above what is explained by earnings losses and weeks of unemployment following displacement....
Displacement Ventilation

DEFF Research Database (Denmark)

Nielsen, Peter Vilhelm

Displacement ventilation is an interesting new type of air distribution principle which should be considered in connection with design of comfort ventilation in both smal1 and large spaces. Research activities on displacement ventilation are large all over the world and new knowledge of design...... methods appears continuously. This book gives an easy introduction to the basis of displacement ventilation and the chapters are written in the order which is used in a design procedure. The main text is extended by five appendices which show some of the new research activities taking place at Aalborg...
Finding New Thermoelectric Compounds Using Crystallographic Data: Atomic Displacement Parameters

Energy Technology Data Exchange (ETDEWEB)

Chakoumakos, B.C.; Mandrus, D.G.; Sales, B.C.; Sharp, J.W.

1999-08-29

A new structure-property relationship is discussed which links atomic displacement parameters (ADPs) and the lattice thermal conductivity of clathrate-like compounds. For many clathrate-like compounds, in which one of the atom types is weakly bound and ''rattles'' within its atomic cage, room temperature ADP information can be used to estimate the room temperature lattice thermal conductivity, the vibration frequency of the ''rattler'', and the temperature dependence of the heat capacity. Neutron data and X-ray crystallography data, reported in the literature, are used to apply this analysis to several promising classes of thermoelectric materials.
Parametric stress analyses for low-level liquid radwaste system piping of ITER subjected to seismic displacements

Energy Technology Data Exchange (ETDEWEB)

Chang, Yoon-Suk [Department of Nuclear Engineering, Kyung Hee University, Yongin (Korea, Republic of); Oh, Chang-Kyun [Materials Engineering Department, KEPCO E& C, Yongin (Korea, Republic of); Kim, Hyun-Su, E-mail: hyunsu@kepco-enc.com [Materials Engineering Department, KEPCO E& C, Yongin (Korea, Republic of)

2015-10-15

The ITER project is aimed at demonstrating the feasibility of fusion as one of the possible energy options. A layout optimization is one of the design concerns for maintaining safety and reliability of the piping, because some piping penetrating the buildings is subjected to large seismic displacements. The objective of this study is to determine an optimum layout for the radioactive liquid transfer piping to withstand a given seismic displacements combined with internal pressure and thermal expansion. To do this, a series of finite element analyses were performed for various layouts. In addition, the feasibility for utilizing the double-walled structure was investigated. Analysis result shows that effects of the internal pressure and thermal expansion on the total stress are very small compared to that of the seismic displacements. Also, the stress as well as the deformation of the double-walled piping is larger than that of the single-walled piping although the difference is not big. Based on this result, an optimum configuration, a spiral along with U shape, is suggested.
Coupled Modeling of Flow, Transport, and Deformation during Hydrodynamically Unstable Displacement in Fractured Rocks

Science.gov (United States)

Jha, B.; Juanes, R.

2015-12-01

Coupled processes of flow, transport, and deformation are important during production of hydrocarbons from oil and gas reservoirs. Effective design and implementation of enhanced recovery techniques such as miscible gas flooding and hydraulic fracturing requires modeling and simulation of these coupled proceses in geologic porous media. We develop a computational framework to model the coupled processes of flow, transport, and deformation in heterogeneous fractured rock. We show that the hydrocarbon recovery efficiency during unstable displacement of a more viscous oil with a less viscous fluid in a fractured medium depends on the mechanical state of the medium, which evolves due to permeability alteration within and around fractures. We show that fully accounting for the coupling between the physical processes results in estimates of the recovery efficiency in agreement with observations in field and lab experiments.
Temperature measurement by thermal strain imaging with diagnostic power ultrasound, with potential for thermal index determination.

Science.gov (United States)

Liang, Hai-Dong; Zhou, Li-Xia; Wells, Peter N T; Halliwell, Michael

2009-05-01

Over the years, there has been a substantial increase in acoustic exposure in diagnostic ultrasound as new imaging modalities with higher intensities and frame rates have been introduced; and more electronic components have been packed into the probe head, so that there is a tendency for it to become hotter. With respect to potential thermal effects, including those which may be hazardous occurring during ultrasound scanning, there is a correspondingly growing need for in vivo techniques to guide the operator as to the actual temperature rise occurring in the examined tissues. Therefore, an in vivo temperature estimator would be of considerable practical value. The commonly-used method of tissue thermal index (TI) measurement with a hydrophone in water could underestimate the actual value of TI (in one report by as much as 2.9 times). To obtain meaningful results, it is necessary to map the temperature elevation in 2-D (or 3-D) space. We present methodology, results and validation of a 2-D spatial and temporal thermal strain ultrasound temperature estimation technique in phantoms, and its apparently novel application in tracking the evolution of heat deposition at diagnostic exposure levels. The same ultrasound probe is used for both transmission and reception. The displacement and thermal strain estimation methods are similar to those used in high-intensity focused ultrasound thermal monitoring. The use of radiofrequency signals permits the application of cross correlation as a similarity measurement for tracking feature displacement. The displacement is used to calculate the thermal strain directly related to the temperature rise. Good agreement was observed between the temperature rise and the ultrasound power and scan duration. Thermal strain up to 1.4% was observed during 4000-s scan. Based on the results obtained for the temperature range studied in this work, the technique demonstrates potential for applicability in phantom (and possibly in vivo tissue
Study on the Optimizing Operation of Exhaust Air Heat Recovery and Solar Energy Combined Thermal Compensation System for Ground-Coupled Heat Pump

Directory of Open Access Journals (Sweden)

Kuan Wang

2017-01-01

Full Text Available This study proposed an exhaust air heat recovery and solar energy combined thermal compensation system (ESTC for ground-coupled heat pumps. Based on the prediction of the next day’s exhaust air temperature and solar irradiance, an optimized thermal compensation (OTC method was developed in this study as well, in which the exhaust air heat recovery compensator and solar energy compensator in the ESTC system run at high efficiency throughout various times of day. Moreover, a modified solar term similar days group (STSDG method was proposed to improve the accuracy of solar irradiance prediction in hazy weather. This modified STSDG method was based on air quality forecast and AQI (air quality index correction factors. Through analyzing the operating parameters and the simulation results of a case study, the ESTC system proved to have good performance and high efficiency in eliminating the heat imbalance by using the OTC method. The thermal compensation quantity per unit energy consumption (TEC of ESTC under the proposed method was 1.25 times as high as that under the traditional operation method. The modified STSDG method also exhibited high accuracy. For the accumulated solar irradiance of the four highest daily radiation hours, the monthly mean absolute percentage error (MAPE between the predicted values and the measured values was 6.35%.

Microflow Mechanism of Oil Displacement by Viscoelastic Hydrophobically Associating Water-Soluble Polymers in Enhanced Oil Recovery

Directory of Open Access Journals (Sweden)

Huiying Zhong

2018-06-01

Full Text Available Polymer flooding plays an important role in enhanced oil recovery (EOR, particularly in China, where partially hydrolyzed polyacrylamide (HPAM and hydrophobically associating water-soluble polymers (HAWP are used in onshore and offshore reservoirs, respectively. Many researchers have highlighted the elasticity of HPAM, which can be used to improve the sweep efficiency, i.e., the ratio of the area swept by an injected fluid to the oil area. On the other hand, fewer studies exist on the elasticity of HAWP. In this study, we investigate the flow of HAWP and Xanthan solutions with identical viscosities in core experiments in terms of elasticity; results reveal that the HAWP can produce shear thickening in the core. The constitutive equation for the HAWP can be obtained using the simulation results matched with the experimental data. On the basis of these experiments, we established a two-phase flow model of a polymer and oil, including the continuity, momentum, constitutive, and phase equations. The volume-of-fluid (VOF method was used to track the interface between the two phases. A complex pore model was established based on the glass-etched model used in the experiment. We used the OpenFOAM platform to solve the mathematical model. The saturation, pressure, and stress tensor distributions were obtained. The results show that the displacement efficiency increased as the elasticity of the polymer increased; accordingly, the elasticity can enlarge the sweep area and decrease the residual oil saturation. As the elasticity increases, the stresses (the first normal stress, second normal stress, and shear stress increase. Finally, the results obtained in this study can be used as a guideline in polymer design, screening, and optimization in the polymer flooding oilfields.
Application of proving-ring technology to measure thermally induced displacements in large boreholes in rock

International Nuclear Information System (INIS)

Patrick, W.C.; Reactor, N.L.; Butkovich, T.R.

1984-03-01

A strain-gauged proving-ring transducer was designed and deployed to measure small diametral displacements in 0.61-m diameter boreholes in rock. The rock surrounding the boreholes was previously heated by storage of spent nuclear fuel assemblies and measurements during post-retrieval cooling of the rock were made. To accomplish this, a transducer was designed to measure displacements in the range of 10 to 100 μm, to function in a time-varying temperature regime of 30 0 to 60 0 C at a relative humidity of 100%, to be of low stiffness, and to be easily and quickly installed. 7 references, 6 figures, 1 table
Increasing CO2 storage in oil recovery

International Nuclear Information System (INIS)

Jessen, K.; Kovscek, A.R.; Orr, F.M. Jr.

2005-01-01

Oil fields offer a significant potential for storing CO 2 and will most likely be the first large scale geological targets for sequestration as the infrastructure, experience and permitting procedures already exist. The problem of co-optimizing oil production and CO 2 storage differs significantly from current gas injection practice due to the cost-benefit imbalance resulting from buying CO 2 for enhanced oil recovery projects. Consequently, operators aim to minimize the amount of CO 2 required to sweep an oil reservoir. For sequestration purposes, where high availability of low cost CO 2 is assumed, the design parameters of enhanced oil recovery processes must be re-defined to optimize the amount of CO 2 left in the reservoir at the time of abandonment. To redefine properly the design parameters, thorough insight into the mechanisms controlling the pore scale displacement efficiency and the overall sweep efficiency is essential. We demonstrate by calculation examples the different mechanisms controlling the displacement behavior of CO 2 sequestration schemes, the interaction between flow and phase equilibrium and how proper design of the injection gas composition and well completion are required to co-optimize oil production and CO 2 storage. [Author
Increasing CO2 storage in oil recovery

International Nuclear Information System (INIS)

Jessen, Kristian; Kovscek, Anthony R.; Orr, Franklin M.

2005-01-01

Oil fields offer a significant potential for storing CO 2 and will most likely be the first large scale geological targets for sequestration as the infrastructure, experience and permitting procedures already exist. The problem of co-optimizing oil production and CO 2 storage differs significantly from current gas injection practice due to the cost-benefit imbalance resulting from buying CO 2 for enhanced oil recovery projects. Consequently, operators aim to minimize the amount of CO 2 required to sweep an oil reservoir. For sequestration purposes, where high availability of low cost CO 2 is assumed, the design parameters of enhanced oil recovery processes must be re-defined to optimize the amount of CO 2 left in the reservoir at the time of abandonment. To redefine properly the design parameters, thorough insight into the mechanisms controlling the pore scale displacement efficiency and the overall sweep efficiency is essential. We demonstrate by calculation examples the different mechanisms controlling the displacement behavior of CO 2 sequestration schemes, the interaction between flow and phase equilibrium and how proper design of the injection gas composition and well completion are required to co-optimize oil production and CO 2 storage
A numerical study on the effects of exhaust locations on energy consumption and thermal environment in an office room served by displacement ventilation

International Nuclear Information System (INIS)

Ahmed, Ahmed Qasim; Gao, Shian; Kareem, Ali Khaleel

2016-01-01

Highlights: • An advanced CFD program was developed and validated successfully. • The relation between the exhaust positions and heat sources was analysed. • Energy saving, thermal comfort and inhaled air quality were studied for 5 cases. • By combining the exhaust with office lamps, a 25% of energy saving was achieved. - Abstract: In an office room, many factors affect the pattern of airflow, thermal comfort, indoor air quality and energy saving. In this study, the effects of the location of exhaust diffusers where the warm and contaminant air is extracted and their relation to room heat sources on thermal comfort and energy saving were investigated numerically for an office served by a displacement ventilation system. The indoor air quality in the breathing level and the inhaled zone were also evaluated. The contaminants were released from window and door frames in order to simulate the contaminants coming from outside. The amount of energy consumption and the indoor thermal environment for various exhaust locations were investigated numerically using the computational fluid dynamics techniques. The results showed that the thermal indoor environment, thermal comfort, quality of indoor air and energy saving were greatly improved by combining the exhaust outlets with some of the room’s heat sources such as ceiling lamps and external walls. In particular, a 25.0% of energy saving was achieved by combining the exhaust diffuser with room’s ceiling lamps. In addition, locating the exhaust diffuser near the heat sources also reduced the cooling coil load by 13.8%. The risk of a large difference in temperature between the head and foot levels, increased particle concentration in the occupied zone, as well as increased energy consumption was also clearly demonstrated when the exhaust and recirculated air outlet (return opening) were combined in one unit in the occupied boundary area that is located at 2 m away from the occupants. Thus, for the optimum energy
Nomarski imaging interferometry to measure the displacement field of micro-electro-mechanical systems

International Nuclear Information System (INIS)

Amiot, Fabien; Roger, Jean Paul

2006-01-01

We propose to use a Nomarski imaging interferometer to measure the out-of-plane displacement field of micro-electro-mechanical systems. It is shown that the measured optical phase arises from both height and slope gradients. By using four integrating buckets, a more efficient approach to unwrap the measured phase is presented,thus making the method well suited for highly curved objects. Slope and height effects are then decoupled by expanding the displacement field on a functions basis, and the inverse transformation is applied to get a displacement field from a measured optical phase map change with a mechanical loading. A measurement reproducibility of approximately 10 pm is achieved, and typical results are shown on a microcantilever under thermal actuation, thereby proving the ability of such a setup to provide a reliable full-field kinematic measurement without surface modification
Dynamic properties of a metal photo-thermal micro-actuator.

Science.gov (United States)

Shi, B; Zhang, H J; Wang, B; Yi, F T; Jiang, J Z; Zhang, D X

2015-02-20

This work presents the design, modeling, simulation, and characterization of a metal bent-beam photo-thermal micro-actuator. The mechanism of actuation is based on the thermal expansion of the micro-actuator which is irradiated by a laser, achieving noncontact control of the power supply. Models for micro-actuators were established and finite-element simulations were carried out to investigate the effects of various parameters on actuation properties. It is found that the thermal expansion coefficient, thermal conductivity, and the geometry size largely affected actuation behavior whereas heat capacity, density, and Young's modulus did not. Experiments demonstrated the dynamic properties of a Ni micro-actuator fabricated via LIGA technology with 1100/30/100 μm (long/wide/thick) arms. The tip displacement of the micro-actuator could achieve up to 42 μm driven by a laser beam (1064 nm wavelength, 1.2 W power, and a driving frequency of 1 HZ). It is found that the tip displacement decreases with increasing laser driving frequency. For 8 Hz driving frequency, 17 μm (peak-valley value) can be still reached, which is large enough for the application as micro-electro-mechanical systems. Metal photo-thermal micro actuators have advantages such as large displacement, simple structure, and large temperature tolerance, and therefore they will be promising in the fields of micro/nanotechnology.
An experimental displacement and over 50 years of tag-recoveries show that monarch butterflies are not true navigators

DEFF Research Database (Denmark)

Mourtisen, Henrik; Derbyshirec, Rachael; Stalleickena, Julia

2013-01-01

grounds. When displaced 2,500 km to the west, the same individuals continued to fly in a general southwest direction, suggesting that monarchs use a simple vector-navigation strategy (i.e., use a specific compass bearing without compensating for displacement). Using over 5 decades of field data, we also...... directionality of migration from north to south is largely because of the presence of geographic barriers that guide individuals toward overwintering sites. Our work suggests that monarchs breeding in eastern North America likely combine simple orientation mechanisms with geographic features that funnel them...
Thermally Actuated Hydraulic Pumps

Science.gov (United States)

Jones, Jack; Ross, Ronald; Chao, Yi

2008-01-01

Thermally actuated hydraulic pumps have been proposed for diverse applications in which direct electrical or mechanical actuation is undesirable and the relative slowness of thermal actuation can be tolerated. The proposed pumps would not contain any sliding (wearing) parts in their compressors and, hence, could have long operational lifetimes. The basic principle of a pump according to the proposal is to utilize the thermal expansion and contraction of a wax or other phase-change material in contact with a hydraulic fluid in a rigid chamber. Heating the chamber and its contents from below to above the melting temperature of the phase-change material would cause the material to expand significantly, thus causing a substantial increase in hydraulic pressure and/or a substantial displacement of hydraulic fluid out of the chamber. Similarly, cooling the chamber and its contents from above to below the melting temperature of the phase-change material would cause the material to contract significantly, thus causing a substantial decrease in hydraulic pressure and/or a substantial displacement of hydraulic fluid into the chamber. The displacement of the hydraulic fluid could be used to drive a piston. The figure illustrates a simple example of a hydraulic jack driven by a thermally actuated hydraulic pump. The pump chamber would be a cylinder containing encapsulated wax pellets and containing radial fins to facilitate transfer of heat to and from the wax. The plastic encapsulation would serve as an oil/wax barrier and the remaining interior space could be filled with hydraulic oil. A filter would retain the encapsulated wax particles in the pump chamber while allowing the hydraulic oil to flow into and out of the chamber. In one important class of potential applications, thermally actuated hydraulic pumps, exploiting vertical ocean temperature gradients for heating and cooling as needed, would be used to vary hydraulic pressures to control buoyancy in undersea research
Status of Enhanced Recovery by Thermal Methods Bilan et orientations de la récupération assistée par méthodes thermiques

Directory of Open Access Journals (Sweden)

Burger J.

2006-11-01

Full Text Available This paper describes the main developments in thermal methods of oil recovery in recent years. Particular attention is devoted to work aimed at improving understanding of the physical and chemical mechanisms involved and at increasing the efficiency of thermal processes. Their preferred domain of application is described and illustrated by typical cases. The contribution of thermal recovery to oil production in the United States and worldwide is discussed. Cet article décrit les principaux développements des méthodes thermiques de récupération du pétrole au cours des dernières années. L'attention est portée aux travaux visant à la compréhension des mécanismes physiques et chimiques mis en jeu et à accroître l'efficacité des procédés thermiques. Leur domaine d'application est présenté et illustré par des cas types. La contribution de la récupération thermique à la production d'hydrocarbures aux Etats-Unis et dans le monde est discutée.
Displacement characteristics of a piezoactuator-based prototype microactuator with a hydraulic displacement amplification system

Energy Technology Data Exchange (ETDEWEB)

Muralidhara [NMAMIT, Nitte (India); Rao, Rathnamala [NITK, Surathkal (India)

2015-11-15

In this study, a new piezoactuator-based prototype microactuator is proposed with a hydraulic displacement amplification system. A piezoactuator is used to deflect a diaphragm which displaces a certain volume of hydraulic fluid into a smaller-diameter piston chamber, thereby amplifying the displacement at the other end of the piston. An electro-mechanical model is implemented to estimate the displacement of a multilayer piezoelectric actuator for the applied input voltage considering the hysteresis behavior. The displacement characteristics of the proposed microactuator are studied for triangular actuation voltage signal. Results of the experiments and simulation of the displacement behavior of the stacked piezoactuator and the amplified displacement of the prototype actuator were compared. Experimental results suggest that the mathematical model developed for the new piezoactuator-based prototype actuator is capable of estimating its displacement behavior accurately, within an error of 1.2%.
Displacement characteristics of a piezoactuator-based prototype microactuator with a hydraulic displacement amplification system

International Nuclear Information System (INIS)

Muralidhara; Rao, Rathnamala

2015-01-01

In this study, a new piezoactuator-based prototype microactuator is proposed with a hydraulic displacement amplification system. A piezoactuator is used to deflect a diaphragm which displaces a certain volume of hydraulic fluid into a smaller-diameter piston chamber, thereby amplifying the displacement at the other end of the piston. An electro-mechanical model is implemented to estimate the displacement of a multilayer piezoelectric actuator for the applied input voltage considering the hysteresis behavior. The displacement characteristics of the proposed microactuator are studied for triangular actuation voltage signal. Results of the experiments and simulation of the displacement behavior of the stacked piezoactuator and the amplified displacement of the prototype actuator were compared. Experimental results suggest that the mathematical model developed for the new piezoactuator-based prototype actuator is capable of estimating its displacement behavior accurately, within an error of 1.2%.
Measuring vulnerability to disaster displacement

Science.gov (United States)

Brink, Susan A.; Khazai, Bijan; Power, Christopher; Wenzel, Friedemann

2015-04-01

Large scale disasters can cause devastating impacts in terms of population displacement. Between 2008 and 2013, on average 27 million people were displaced annually by disasters (Yonetani 2014). After large events such as hurricane Katrina or the Port-au-Prince earthquake, images of inadequate public shelter and concerns about large scale and often inequitable migration have been broadcast around the world. Population displacement can often be one of the most devastating and visible impacts of a natural disaster. Despite the importance of population displacement in disaster events, measures to understand the socio-economic vulnerability of a community often use broad metrics to estimate the total socio-economic risk of an event rather than focusing on the specific impacts that a community faces in a disaster. Population displacement is complex and multi-causal with the physical impact of a disaster interacting with vulnerability arising from the response, environmental issues (e.g., weather), cultural concerns (e.g., expectations of adequate shelter), and many individual factors (e.g., mobility, risk perception). In addition to the complexity of the causes, population displacement is difficult to measure because of the wide variety of different terms and definitions and its multi-dimensional nature. When we speak of severe population displacement, we may refer to a large number of displaced people, an extended length of displacement or associated difficulties such as poor shelter quality, risk of violence and crime in shelter communities, discrimination in aid, a lack of access to employment or other difficulties that can be associated with large scale population displacement. We have completed a thorough review of the literature on disaster population displacement. Research has been conducted on historic events to understand the types of negative impacts associated with population displacement and also the vulnerability of different groups to these impacts. We
Emittance growth in displaced, space-charge-dominated beams with energy spread

International Nuclear Information System (INIS)

Barnard, J.J.; Miller, J.; Haber, I.

1993-01-01

Conversion of transverse energy associated with the coherent motion of displaced beams into thermal energy, and thus emittance growth, has been predicted theoretically by a number of authors. Here, they authors show, using 2-D particle-in-cell simulations, that emittance growth is inhibited for tune depressed beams, if the energy spread of the beam is not too large. Further, using a uniform density model to calculate the space charge field of the beam, they numerically determine the criteria for emittance growth as a function of tune depression, energy spread, and beam displacement over a wide range of parameters. A theoretical interpretation of the results is presented. This study is applicable to an inertial fusion reactor driven by a heavy ion accelerator
Resonant neutron-induced atomic displacements

Energy Technology Data Exchange (ETDEWEB)

Elmaghraby, Elsayed K., E-mail: e.m.k.elmaghraby@gmail.com

2017-05-01

Highlights: • Neutron induced atomic displacements was investigated based on scattering of energy of neutron. • Model for cascade function (multiplication of displacements with increasing energy transfer) was proposed and justified. • Parameterizations for the dpa induced in all elements were performed. • Table containing all necessary parameters to calculate the displacement density induced by neutron is given. • Contribution of non resonance displacement and resonant-neutron induced displacements are distinguished. - Abstract: A model for displacement cascade function was modified to account for the continuous variation of displacement density in the material in response to neutron exposure. The model is based on the Gaussian distribution of displacement energies of atoms in a material. Analytical treatment for moderated epithermal neutron field was given in which the displacement density was divided into two terms, discrete-resonance term and continuum term. Calculation are done for all isotopes using ENDF/B VII.1 data files and temperature dependent cross section library. Weighted elemental values were reported a fitting was performed to obtain energy-dependent formula of displacement density and reduce the number of parameters. Results relevant the present specification of the cascade function are tabulated for each element to enable calculation of displacement density at any value of displacement energy in the between 5 eV and 55 eV.
State of the Art Review on Theoretical Tribology of Fluid Power Displacement Machines

DEFF Research Database (Denmark)

Cerimagic, Remzija; Johansen, Per; Andersen, Torben O.

2016-01-01

machines, and also the work done to validate the theoretical models. This review is not a complete historical account, but aim to describe current trends in fluid power displacement machine tribology. The review considers the rheological models used in the theoretical approaches, the modeling...... and wear mechanisms in the lubricating gaps in fluid power machines is confined to simulation models, as experimental treatments of these mechanisms are very difficult. The aim of this paper is a state of the art review on the theoretical work for the design and optimization of fluid power displacement...... of elastohydrodynamic effects, the modeling of thermal effects, and finally the experimental validation of the theoretical models....
A new solution of measuring thermal response of prestressed concrete bridge girders for structural health monitoring

International Nuclear Information System (INIS)

Jiao, Pengcheng; Borchani, Wassim; Hasni, Hassene; Lajnef, Nizar

2017-01-01

This study develops a novel buckling-based mechanism to measure the thermal response of prestressed concrete bridge girders under continuous temperature changes for structural health monitoring. The measuring device consists of a bilaterally constrained beam and a piezoelectric polyvinylidene fluoride transducer that is attached to the beam. Under thermally induced displacement, the slender beam is buckled. The post-buckling events are deployed to convert the low-rate and low-frequency excitations into localized high-rate motions and, therefore, the attached piezoelectric transducer is triggered to generate electrical signals. Attaching the measuring device to concrete bridge girders, the electrical signals are used to detect the thermal response of concrete bridges. Finite element simulations are conducted to obtain the displacement of prestressed concrete girders under thermal loads. Using the thermal-induced displacement as input, experiments are carried out on a 3D printed measuring device to investigate the buckling response and corresponding electrical signals. A theoretical model is developed based on the nonlinear Euler–Bernoulli beam theory and large deformation assumptions to predict the buckling mode transitions of the beam. Based on the presented theoretical model, the geometry properties of the measuring device can be designed such that its buckling response is effectively controlled. Consequently, the thermally induced displacement can be designed as limit states to detect excessive thermal loads on concrete bridge girders. The proposed solution sufficiently measures the thermal response of concrete bridges. (paper)
A new solution of measuring thermal response of prestressed concrete bridge girders for structural health monitoring

Science.gov (United States)

Jiao, Pengcheng; Borchani, Wassim; Hasni, Hassene; Lajnef, Nizar

2017-08-01

This study develops a novel buckling-based mechanism to measure the thermal response of prestressed concrete bridge girders under continuous temperature changes for structural health monitoring. The measuring device consists of a bilaterally constrained beam and a piezoelectric polyvinylidene fluoride transducer that is attached to the beam. Under thermally induced displacement, the slender beam is buckled. The post-buckling events are deployed to convert the low-rate and low-frequency excitations into localized high-rate motions and, therefore, the attached piezoelectric transducer is triggered to generate electrical signals. Attaching the measuring device to concrete bridge girders, the electrical signals are used to detect the thermal response of concrete bridges. Finite element simulations are conducted to obtain the displacement of prestressed concrete girders under thermal loads. Using the thermal-induced displacement as input, experiments are carried out on a 3D printed measuring device to investigate the buckling response and corresponding electrical signals. A theoretical model is developed based on the nonlinear Euler-Bernoulli beam theory and large deformation assumptions to predict the buckling mode transitions of the beam. Based on the presented theoretical model, the geometry properties of the measuring device can be designed such that its buckling response is effectively controlled. Consequently, the thermally induced displacement can be designed as limit states to detect excessive thermal loads on concrete bridge girders. The proposed solution sufficiently measures the thermal response of concrete bridges.
Recovery and purification of ethylene

Science.gov (United States)

Reyneke, Rian [Katy, TX; Foral, Michael J [Aurora, IL; Lee, Guang-Chung [Houston, TX; Eng, Wayne W. Y. [League City, TX; Sinclair, Iain [Warrington, GB; Lodgson, Jeffery S [Naperville, IL

2008-10-21

A process for the recovery and purification of ethylene and optionally propylene from a stream containing lighter and heavier components that employs an ethylene distributor column and a partially thermally coupled distributed distillation system.
Development of Displacement Gages Exposed to Solid Rocket Motor Internal Environments

Science.gov (United States)

Bolton, D. E.; Cook, D. J.

2003-01-01

The Space Shuttle Reusable Solid Rocket Motor (RSRM) has three non-vented segment-to-segment case field joints. These joints use an interference fit J-joint that is bonded at assembly with a Pressure Sensitive Adhesive (PSA) inboard of redundant O-ring seals. Full-scale motor and sub-scale test article experience has shown that the ability to preclude gas leakage past the J-joint is a function of PSA type, joint moisture from pre-assembly humidity exposure, and the magnitude of joint displacement during motor operation. To more accurately determine the axial displacements at the J-joints, two thermally durable displacement gages (one mechanical and one electrical) were designed and developed. The mechanical displacement gage concept was generated first as a non-electrical, self-contained gage to capture the maximum magnitude of the J-joint motion. When it became feasible, the electrical displacement gage concept was generated second as a real-time linear displacement gage. Both of these gages were refined in development testing that included hot internal solid rocket motor environments and simulated vibration environments. As a result of this gage development effort, joint motions have been measured in static fired RSRM J-joints where intentional venting was produced (Flight Support Motor #8, FSM-8) and nominal non-vented behavior occurred (FSM-9 and FSM-10). This data gives new insight into the nominal characteristics of the three case J-joint positions (forward, center and aft) and characteristics of some case J-joints that became vented during motor operation. The data supports previous structural model predictions. These gages will also be useful in evaluating J-joint motion differences in a five-segment Space Shuttle solid rocket motor.

Quantum-teleportation benchmarks for independent and identically distributed spin states and displaced thermal states

International Nuclear Information System (INIS)

Guta, Madalin; Bowles, Peter; Adesso, Gerardo

2010-01-01

A successful state-transfer (or teleportation) experiment must perform better than the benchmark set by the 'best' measure and prepare procedure. We consider the benchmark problem for the following families of states: (i) displaced thermal equilibrium states of a given temperature; (ii) independent identically prepared qubits with a completely unknown state. For the first family we show that the optimal procedure is heterodyne measurement followed by the preparation of a coherent state. This procedure was known to be optimal for coherent states and for squeezed states with the 'overlap fidelity' as the figure of merit. Here, we prove its optimality with respect to the trace norm distance and supremum risk. For the second problem we consider n independent and identically distributed (i.i.d.) spin-(1/2) systems in an arbitrary unknown state ρ and look for the measurement-preparation pair (M n ,P n ) for which the reconstructed state ω n :=P n circle M n (ρ xn ) is as close as possible to the input state (i.e., parallel ω n -ρ xn parallel 1 is small). The figure of merit is based on the trace norm distance between the input and output states. We show that asymptotically with n this problem is equivalent to the first one. The proof and construction of (M n ,P n ) uses the theory of local asymptotic normality developed for state estimation which shows that i.i.d. quantum models can be approximated in a strong sense by quantum Gaussian models. The measurement part is identical to 'optimal estimation', showing that 'benchmarking' and estimation are closely related problems in the asymptotic set up.
Evidence for hydrogen-assisted recovery of cold-worked palladium: hydrogen solubility and mechanical properties studies

Directory of Open Access Journals (Sweden)

Maria Ferrer

2017-07-01

Full Text Available The influence of hydrogen as an agent to accelerate the thermal recovery of cold-worked palladium has been investigated. The techniques used to characterize the effects of hydrogen on the thermal recovery of palladium were hydrogen solubility and mechanical property measurements. Results show that the presence of modest amounts of hydrogen during annealing of cold-worked palladium does enhance the degree of thermal recovery, with a direct correlation between the amount of hydrogen during annealing and the degree of recovery. The results indicate that the damage resulting from cold-working palladium can be more effectively and efficiently reversed by suitable heat treatments in the presence of appropriate amounts of hydrogen, as compared to heat treatment in vacuum. The somewhat novel technique of using changes in the hydrogen solubility of palladium as an indicator of thermal recovery has been validated and complements the more traditional technique of mechanical property measurements.
Job Displacement and Crime

DEFF Research Database (Denmark)

Bennett, Patrick; Ouazad, Amine

theory of crime. Marital dissolution is more likely post-displacement, and we find small intra-family externalities of adult displacement on younger family members’ crime. The impact of displacement on crime is stronger in municipalities with higher capital and labor income inequalities....
Microbial Enhanced Oil Recovery: 3D Simulation with Gravity Effects

DEFF Research Database (Denmark)

Nielsen, Sidsel Marie; Jessen, K.; Shapiro, Alexander

2010-01-01

Microbial enhanced oil recovery (MEOR) utilizes the activity of microorganisms, where microorganisms simultaneously grow in a reservoir and convert substrate into recovery enhancing products (usually, surfactants). In order to predict the performance of a MEOR process, a simulation tool is required...... using an operator splitting technique. To the best of our knowledge, this has resulted in the first full 3D MEOR streamline simulator. For verification purposes, we compare results from our streamline MEOR simulator to those of a conventional finite difference approach for 1D and 2D displacement...
Development of More Effective Biosurfactants for Enhanced Oil Recovery

Energy Technology Data Exchange (ETDEWEB)

McInerney, J.J.; Han, S.O.; Maudgalya, S.; Mouttaki, H.; Folmsbee, M.; Knapp, R.; Nagle, D.; Jackson, B.E.; Stuadt, M.; Frey, W.

2003-01-16

The objectives of this were two fold. First, core displacement studies were done to determine whether microbial processes could recover residual oil at elevated pressures. Second, the importance of biosurfactant production for the recovery of residual oil was studies. In these studies, a biosurfactant-producing, microorganisms called Bacillus licheniformis strain JF-2 was used. This bacterium produces a cyclic peptide biosurfactant that significantly reduces the interfacial tension between oil and brine (7). The use of a mutant deficient in surfactant production and a mathematical MEOR simulator were used to determine the major mechanisms of oil recovery by these two strains.
Displacement monitoring and modelling of a high-speed railway bridge using C-band Sentinel-1 data

Science.gov (United States)

Huang, Qihuan; Crosetto, Michele; Monserrat, Oriol; Crippa, Bruno

2017-06-01

Bridge displacement monitoring is one of the key components of bridge structural health monitoring. Traditional methods, usually based on limited sets of sensors mounted on a given bridge, collect point-like deformation information and have the disadvantage of providing incomplete displacement information. In this paper, a Persistent Scatterer Interferometry (PSI) approach is used to monitor the displacements of the Nanjing Dashengguan Yangtze River high-speed railway bridge. Twenty-nine (29) European Space Agency Sentinel-1A images, acquired from April 25, 2015 to August 5, 2016, were used in the PSI analysis. A total of 1828 measurement points were selected on the bridge. The results show a maximum longitudinal displacement of about 150 mm on each side of the bridge. The measured displacements showed a strong correlation with the environmental temperature at the time the images used were acquired, indicating that they were due to thermal expansion of the bridge. At each pier, a regression model based on the PSI-measured displacements was compared with a model based on in-situ measurements. The good agreement of these models demonstrates the capability of the PSI technique to monitor long-span railway bridge displacements. By comparing the modelled displacements and dozens of PSI measurements, we show how the performance of movable bearings can be evaluated. The high density of the PSI measurement points is advantageous for the health monitoring of the entire bridge.
Effects of chlorimuron ethyl on terrestrial and wetland plants: Levels of, and time to recovery following sublethal exposure

International Nuclear Information System (INIS)

Carpenter, David; Boutin, Céline; Allison, Jane E.

2013-01-01

Current pesticide registration guidelines call for short-term testing of plants; long-term effects on vegetative parts and reproduction remain untested. The aims of our study were to determine level of recovery and recovery times for plants exposed to the sulfonylurea herbicide chlorimuron ethyl using data collected from single species, dose–response greenhouse experiments. The nine terrestrial and eight wetland species tested showed variable levels of recovery and recovery timeframes. Many species (six terrestrial and five wetland) were vegetatively stunted at sublethal doses and were reproductively impaired. Full recovery did not occur at all doses and maximum recovery times varied from 3 to 15 weeks in this controlled environment. In a complex community, affected species may be displaced by tolerant species, through interspecific competition, before they fully recover. It is plausible that individual populations could be diminished or eliminated through reduced seedbank inputs (annuals and perennials) and asexual reproduction (perennials). - Highlights: ► Native terrestrial and wetland plants were used to assess the risks of herbicide drift. ► Vegetative and reproductive health endpoints were evaluated over time. ► Recovery rates were found to be both species and dose dependant. ► Reproductive recovery does not always equal vegetative recovery. ► Susceptible species may be displaced by resilient or resistant species. - Capsule: This study serves to bridge the gap between simplified short-term greenhouse tests and effects of herbicides on recovery of non-target plant species after sublethal exposures.
Final report for the Iowa Livestock Industry Waste Characterization and Methane Recovery Information Dissemination Project

Energy Technology Data Exchange (ETDEWEB)

Garrison, M.V.; Richard, Thomas L

2001-11-13

This report summarizes analytical methods, characterizes Iowa livestock wastes, determines fossil fuel displacement by methane use, assesses the market potential, and offers recommendations for the implementation of methane recovery technologies.
Ventilation with heat recovery

DEFF Research Database (Denmark)

Tommerup, Henrik M.; Svendsen, Svend

2005-01-01

This paper presents the experiences from the use of ventilation with heat recovery in several experimental single-family houses developed and built within the last four years to meet the new Danish energy requirements of 2005. Included are descriptions of the ventilation system components...... and the main functional demands as well as measurements of the thermal efficiency, electricity consumptions and building air tightness. The paper addresses the aspects of minimizing the heat loss from the duct system and the heat recovery unit (when placed in an unheated attic space) in order to obtain...
Waste heat recovery for offshore applications

DEFF Research Database (Denmark)

Pierobon, Leonardo; Kandepu, Rambabu; Haglind, Fredrik

2012-01-01

vary in the range 20-30%. There are several technologies available for onshore gas turbines (and low/medium heat sources) to convert the waste heat into electricity. For offshore applications it is not economical and practical to have a steam bottoming cycle to increase the efficiency of electricity...... production, due to low gas turbine outlet temperature, space and weight restrictions and the need for make-up water. A more promising option for use offshore is organic Rankine cycles (ORC). Moreover, several oil and gas platforms are equipped with waste heat recovery units to recover a part of the thermal...... energy in the gas turbine off-gas using heat exchangers, and the recovered thermal energy acts as heat source for some of the heat loads on the platform. The amount of the recovered thermal energy depends on the heat loads and thus the full potential of waste heat recovery units may not be utilized...
Considering Angle Selection When Using Ultrasound Electrode Displacement Elastography to Evaluate Radiofrequency Ablation of Tissues

Science.gov (United States)

Li, Qiang; Chen, Pin-Yu; Wang, Chiao-Yin; Liu, Hao-Li; Teng, Jianfu

2014-01-01

Percutaneous radiofrequency ablation (RFA) is a minimally invasive treatment to thermally destroy tumors. Ultrasound-based electrode-displacement elastography is an emerging technique for evaluating the region of RFA-induced lesions. The angle between the imaging probe and the RFA electrode can influence electrode-displacement elastography when visualizing the ablation zone. We explored the angle effect on electrode-displacement elastography to measure the ablation zone. Phantoms embedded with meatballs were fabricated and then ablated using an RFA system to simulate RFA-induced lesions. For each phantom, a commercial ultrasound scanner with a 7.5 MHz linear probe was used to acquire raw image data at different angles, ranging from 30° to 90° at increments of 10°, to construct electrode-displacement images and facilitate comparisons with tissue section images. The results revealed that the ablation regions detected using electrode-displacement elastography were highly correlated with those from tissue section images when the angle was between 30° and 60°. However, the boundaries of lesions were difficult to distinguish, when the angle was larger than 60°. The experimental findings suggest that angle selection should be considered to achieve reliable electrode-displacement elastography to describe ablation zones. PMID:24971347
Displacement Models for THUNDER Actuators having General Loads and Boundary Conditions

Science.gov (United States)

Wieman, Robert; Smith, Ralph C.; Kackley, Tyson; Ounaies, Zoubeida; Bernd, Jeff; Bushnell, Dennis M. (Technical Monitor)

2001-01-01

This paper summarizes techniques for quantifying the displacements generated in THUNDER actuators in response to applied voltages for a variety of boundary conditions and exogenous loads. The PDE (partial differential equations) models for the actuators are constructed in two steps. In the first, previously developed theory quantifying thermal and electrostatic strains is employed to model the actuator shapes which result from the manufacturing process and subsequent repoling. Newtonian principles are then employed to develop PDE models which quantify displacements in the actuator due to voltage inputs to the piezoceramic patch. For this analysis, drive levels are assumed to be moderate so that linear piezoelectric relations can be employed. Finite element methods for discretizing the models are developed and the performance of the discretized models are illustrated through comparison with experimental data.
Enzymes for Enhanced Oil Recovery (EOR)

Energy Technology Data Exchange (ETDEWEB)

Nasiri, Hamidreza

2011-04-15

Primary oil recovery by reservoir pressure depletion and secondary oil recovery by waterflooding usually result in poor displacement efficiency. As a consequence there is always some trapped oil remaining in oil reservoirs. Oil entrapment is a result of complex interactions between viscous, gravity and capillary forces. Improving recovery from hydrocarbon fields typically involves altering the relative importance of the viscous and capillary forces. The potential of many EOR methods depends on their influence on fluid/rock interactions related to wettability and fluid/fluid interactions reflected in IFT. If the method has the potential to change the interactions favorably, it may be considered for further investigation, i.e. core flooding experiment, pilot and reservoir implementation. Enzyme-proteins can be introduced as an enhanced oil recovery method to improve waterflood performance by affecting interactions at the oil-water-rock interfaces. An important part of this thesis was to investigate how selected enzymes may influence wettability and capillary forces in a crude oil-brine-rock system, and thus possibly contribute to enhanced oil recovery. To investigate further by which mechanisms selected enzyme-proteins may contribute to enhance oil recovery, groups of enzymes with different properties and catalytic functions, known to be interfacially active, were chosen to cover a wide range of possible effects. These groups include (1) Greenzyme (GZ) which is a commercial EOR enzyme and consists of enzymes and stabilizers (surfactants), (2) The Zonase group consists of two types of pure enzyme, Zonase1 and Zonase2 which are protease enzymes and whose catalytic functions are to hydrolyze (breakdown) peptide bonds, (3) The Novozyme (NZ) group consists of three types of pure enzyme, NZ2, NZ3 and NZ6 which are esterase enzymes and whose catalytic functions are to hydrolyze ester bonds, and (4) Alpha-Lactalbumin ( -La) which is an important whey protein. The effect of
Shape memory thermal conduction switch

Science.gov (United States)

Vaidyanathan, Rajan (Inventor); Krishnan, Vinu (Inventor); Notardonato, William U. (Inventor)

2010-01-01

A thermal conduction switch includes a thermally-conductive first member having a first thermal contacting structure for securing the first member as a stationary member to a thermally regulated body or a body requiring thermal regulation. A movable thermally-conductive second member has a second thermal contacting surface. A thermally conductive coupler is interposed between the first member and the second member for thermally coupling the first member to the second member. At least one control spring is coupled between the first member and the second member. The control spring includes a NiTiFe comprising shape memory (SM) material that provides a phase change temperature <273 K, a transformation range <40 K, and a hysteresis of <10 K. A bias spring is between the first member and the second member. At the phase change the switch provides a distance change (displacement) between first and second member by at least 1 mm, such as 2 to 4 mm.
Internal Displacement: Livelihood saving responses

OpenAIRE

Deborah Hines

2001-01-01

Deborah Hines explores how to assist the internally displaced and those prone to displacement. She considers the major causes of internal displacement, making the case for a more comprehensive set of policy and operational actions in response to situations of internal displacement. Development (2001) 44, 34–39. doi:10.1057/palgrave.development.1110289
Investigation of thermal integration between biogas production and upgrading

International Nuclear Information System (INIS)

Zhang, Xiaojing; Yan, Jinying; Li, Hailong; Chekani, Shabnam; Liu, Loncheng

2015-01-01

Highlights: • Identify thermal characteristics of amine-based biogas upgrading for waste heat recovery. • Identify thermal characteristics of AD biogas production as sink for heat recovery. • Evaluation of thermal integration between biogas production and upgrading to improve overall energy efficiency. • Cost analysis applied for the economic feasibility of the thermal integration. • Using the principles of target design and system integration for connected thermal processes. - Abstract: Thermal integration of anaerobic digestion (AD) biogas production with amine-based chemical absorption biogas upgrading has been studied to improve the overall efficiency of the intergraded system. The thermal characteristics have been investigated for industrial AD raw biogas production and amine-based chemical absorption biogas upgrading. The investigation provides a basic understanding for the possibilities of energy saving through thermal integration. The thermal integration is carried out through well-defined cases based on the thermal characteristics of the biogas production and the biogas upgrading. The following factors are taken into account in the case study: thermal conditions of sub-systems, material and energy balances, cost issues and main benefits. The potential of heat recovery has been evaluated to utilise the waste heat from amine-based upgrading process for the use in the AD biogas production. The results show that the thermal integration has positive effects on improving the overall energy efficiency of the integrated biogas plant. Cost analysis shows that the thermal integration is economically feasible
Final report for the Iowa Livestock Industry Waste Characterization and Methane Recovery Information Dissemination Project; FINAL

International Nuclear Information System (INIS)

Garrison, M.V.; Richard, Thomas L

2001-01-01

This report summarizes analytical methods, characterizes Iowa livestock wastes, determines fossil fuel displacement by methane use, assesses the market potential, and offers recommendations for the implementation of methane recovery technologies
Molecular dynamics studies of displacement cascades

International Nuclear Information System (INIS)

Averback, R.S.; Hsieh, Horngming; Diaz de la Rubia, T.

1990-02-01

Molecular-dynamics simulations of cascades in Cu and Ni with primary-knock-on energies up to 5 keV and lattice temperatures in the range 0 K--700 K are described. Interatomic forces were represented by either the Gibson II (Cu) or Johnson-Erginsoy (Ni) potentials in most of this work, although some simulations using ''Embedded Atom Method'' potentials, e.g., for threshold events in Ni 3 Al, are also presented. The results indicate that the primary state of damage produced by displacement cascades is controlled by two phenomena, replacement collision sequences during the collisional phase of the cascade and local melting during the thermal spike. As expected, the collisional phase is rather similar in Cu and Ni, however, the thermal spike is of longer duration and has a more pronounced influence in Cu than Ni. When the ambient temperature of the lattice is increased, the melt zones are observed to both increase in size and cool more slowly. This has the effect of reducing defect production and enhancing atomic mixing and disordering. The implications of these results for defect production, cascade collapse, atomic disordering will be discussed. 34 refs., 7 figs., 2 tabs
Foam rheology in porous media and enhanced oil recovery potential

International Nuclear Information System (INIS)

Burley, R.

1985-01-01

Previous studies using foam as a mobility control agent in partially depleted oil wells have shown that foam has a potential for enhancing oil recovery after primary water flooding. The characteristics of foam as indicated by the results of several studies point to three potential applications of foam in oil recovery processes. These are: Improving the displacement efficiency of gas-drive processes (mobility control). Improving the sweep efficiency of other fluid injection processes (mobility control and flow impediment). Restricting the flow of undesired fluids and plugging of high permeable oil 'thief' zones (partial or total pore blockage). (author)
Thermal Plumes in Ventilated Rooms

DEFF Research Database (Denmark)

Kofoed, Peter; Nielsen, Peter V.

The design of a displacement ventilation system involves determination of the flow rate in the thermal plumes. The flow rate in the plumes and the vertical temperature gradient influence each other, and they are influenced by many factors. This paper shows some descriptions of these effects....

A pratical case of a pipeline deformation by transverse and longitudinal thermal gradient

International Nuclear Information System (INIS)

Franca Filho, J.L. de; Souza, H.S.; Ribeiro, S.V.G.

1982-01-01

A pratical case of pipeline deformation due to a thermal gradient that exist in the cross section and along its length is presented. From an approximation of the temperature profile obtained by measurements made in the field and taking into account the boundary conditions of the structure, its displacements are calculated for comparison with the actual values observed. The analytical calculation of the displacements fields and stress fields are executed, using the concept of thermal momentum in the section. (EG) [pt
Strain Recovery by TiNi Element Under Fast Heating

Science.gov (United States)

Volkov, Aleksandr E.; Miszuris, Wiktoria; Volkova, Natalia A.

2018-01-01

A theoretical and experimental study of strain recovery under fast heating of a shape memory alloy (SMA) rod preliminarily stretched in the martensitic state is carried out. Two theoretical models are considered: instantaneous heating and heating with temperature variation during a finite time. In the first case, it is supposed that the straight SMA rod experiences an instantaneous reverse martensitic transformation, and in the second the transformation is supposed to progress at a rate corresponding to the temperature rate. Analytical expression for the time dependence of the rod free-end displacement is obtained. In the experiment, a wire specimen made of titanium-nickel SMA was heated by a short impulse of electric current. The variation of the specimen length in time was registered. Thus, it has been shown that the minimum operation time of an SMA actuator (time needed for the strain recovery) can be reduced to 20 µs. Comparison of the theoretical results with the experimental ones leads to the conclusion that the displacement variation in time is controlled by the rate of heating and the inertia of the specimen. The incubation time of the martensitic transformation on the microscale apparently is estimated as less than 1 µs.
Potential for spatial displacement of Cook Inlet beluga whales by anthropogenic noise in critical habitat

Science.gov (United States)

Small, Robert J.; Brost, Brian M.; Hooten, Mevin B.; Castellote, Manuel; Mondragon, Jeffrey

2017-01-01

The population of beluga whales in Cook Inlet, Alaska, USA, declined by nearly half in the mid-1990s, primarily from an unsustainable harvest, and was listed as endangered in 2008. In 2014, abundance was ~340 whales, and the population trend during 1999-2014 was -1.3% yr-1. Cook Inlet beluga whales are particularly vulnerable to anthropogenic impacts, and noise that has the potential to reduce communication and echolocation range considerably has been documented in critical habitat; thus, noise was ranked as a high potential threat in the Cook Inlet beluga Recovery Plan. The current recovery strategy includes research on effects of threats potentially limiting recovery, and thus we examined the potential impact of anthropogenic noise in critical habitat, specifically, spatial displacement. Using a subset of data on anthropogenic noise and beluga detections from a 5 yr acoustic study, we evaluated the influence of noise events on beluga occupancy probability. We used occupancy models, which account for factors that affect detection probability when estimating occupancy, the first application of these models to examine the potential impacts of anthropogenic noise on marine mammal behavior. Results were inconclusive, primarily because beluga detections were relatively infrequent. Even though noise metrics (sound pressure level and noise duration) appeared in high-ranking models as covariates for occupancy probability, the data were insufficient to indicate better predictive ability beyond those models that only included environmental covariates. Future studies that implement protocols designed specifically for beluga occupancy will be most effective for accurately estimating the effect of noise on beluga displacement.
WASTE HEAT RECOVERY IN HEAT PUMP SYSTEMS: SOLUTION TO REDUCE GLOBAL WARMING

Directory of Open Access Journals (Sweden)

Y. Baradey

2015-11-01

Full Text Available Energy conversion technologies, where waste heat recovery systems are included, have received significant attention in recent years due to reasons that include depletion of fossil fuel, increasing oil prices, changes in climatic conditions, and global warming. For low temperature applications, there are many sources of thermal waste heat, and several recovery systems and potential useful applications have been proposed by researchers [1-4]. In addition, many types of equipment are used to recover waste thermal energy from different systems at low, medium, and high temperature applications, such as heat exchangers, waste heat recovery boiler, thermo-electric generators, and recuperators. In this paper, the focus is on waste heat recovery from air conditioners, and an efficient application of these energy resources. Integration of solar energy with heat pump technologies and major factors that affect the feasibility of heat recovery systems have been studied and reviewed as well. KEYWORDS: waste heat recovery; heat pump.
Thermal Plumes in Ventilated Rooms

DEFF Research Database (Denmark)

Kofoed, P.; Nielsen, Peter Vilhelm

The main objective of ventilation is to provide good air quality for the occupants. For this purpose the necessary ventilating air change rate must be determined. Within displacement ventilation the estimation is closely related to the air flow rate in the thermal plumes when an air quality based...
Modeling of displacement damage in silicon carbide detectors resulting from neutron irradiation

Science.gov (United States)

Khorsandi, Behrooz

There is considerable interest in developing a power monitor system for Generation IV reactors (for instance GT-MHR). A new type of semiconductor radiation detector is under development based on silicon carbide (SiC) technology for these reactors. SiC has been selected as the semiconductor material due to its superior thermal-electrical-neutronic properties. Compared to Si, SiC is a radiation hard material; however, like Si, the properties of SiC are changed by irradiation by a large fluence of energetic neutrons, as a consequence of displacement damage, and that irradiation decreases the life-time of detectors. Predictions of displacement damage and the concomitant radiation effects are important for deciding where the SiC detectors should be placed. The purpose of this dissertation is to develop computer simulation methods to estimate the number of various defects created in SiC detectors, because of neutron irradiation, and predict at what positions of a reactor, SiC detectors could monitor the neutron flux with high reliability. The simulation modeling includes several well-known---and commercial---codes (MCNP5, TRIM, MARLOWE and VASP), and two kinetic Monte Carlo codes written by the author (MCASIC and DCRSIC). My dissertation will highlight the displacement damage that may happen in SiC detectors located in available positions in the OSURR, GT-MHR and IRIS. As extra modeling output data, the count rates of SiC for the specified locations are calculated. A conclusion of this thesis is SiC detectors that are placed in the thermal neutron region of a graphite moderator-reflector reactor have a chance to survive at least one reactor refueling cycle, while their count rates are acceptably high.
Experimental approach to investigate the constrained recovery behavior of coiled monofilament polymer fibers

Science.gov (United States)

Mendes, S. S.; Nunes, L. C. S.

2017-11-01

The aim of this work is to propose a new approach for investigating the thermo-mechanical behavior of coiled oriented polymer fibers with fixed ends and promote an understanding of the actuation response of coiled polymers in constrained recovery applications. In the proposed experimental methodology, a coiled fiber was pre-stretched by 50% and the distance between its ends remained constant, then it was subjected to a heating-cooling cycle ranging from 30 °C to 120 °C and the induced restoring force was measured. Based on these measurements, axial deformation and shear strain were obtained from full-field displacements extracted by the digital image correlation method from images of the coiled fiber. Three coiled fibers with different initial pitch angles were manufactured, and samples with lengths of 15 mm and 20 mm were tested. Bias angles and coil radius were also estimated using the experimental data associated with the helical spring theory. Results show that significant shape changes can be noticed above the glass transition temperature (47 °C), and these changes induce variation in the resultant forces. The effects of thermal softening and thermal contraction for a modest negative thermal expansion coefficient became evident at temperatures ranging from ∼47 °C to ∼90 °C, while the response of a coiled homochiral polymer fiber was achieved at temperatures close to 90 °C. During the cooling process, saturated states of the axial deformation and shear strain of the coiled fibers were observed at temperatures between 120 °C and 100 °C.
Microbial enhanced oil recovery and compositions therefor

Science.gov (United States)

Bryant, Rebecca S.

1990-01-01

A method is provided for microbial enhanced oil recovery, wherein a combination of microorganisms is empirically formulated based on survivability under reservoir conditions and oil recovery efficiency, such that injection of the microbial combination may be made, in the presence of essentially only nutrient solution, directly into an injection well of an oil bearing reservoir having oil present at waterflood residual oil saturation concentration. The microbial combination is capable of displacing residual oil from reservoir rock, which oil may be recovered by waterflooding without causing plugging of the reservoir rock. Further, the microorganisms are capable of being transported through the pores of the reservoir rock between said injection well and associated production wells, during waterflooding, which results in a larger area of the reservoir being covered by the oil-mobilizing microorganisms.
Deterministic Lateral Displacement: The Next-Generation CAR T-Cell Processing?

Science.gov (United States)

Campos-González, Roberto; Skelley, Alison M; Gandhi, Khushroo; Inglis, David W; Sturm, James C; Civin, Curt I; Ward, Tony

2018-01-01

Reliable cell recovery and expansion are fundamental to the successful scale-up of chimeric antigen receptor (CAR) T cells or any therapeutic cell-manufacturing process. Here, we extend our previous work in whole blood by manufacturing a highly parallel deterministic lateral displacement (DLD) device incorporating diamond microposts and moving into processing, for the first time, apheresis blood products. This study demonstrates key metrics of cell recovery (80%) and platelet depletion (87%), and it shows that DLD T-cell preparations have high conversion to the T-central memory phenotype and expand well in culture, resulting in twofold greater central memory cells compared to Ficoll-Hypaque (Ficoll) and direct magnetic approaches. In addition, all samples processed by DLD converted to a majority T-central memory phenotype and did so with less variation, in stark contrast to Ficoll and direct magnetic prepared samples, which had partial conversion among all donors (automated while simultaneously addressing multiple steps when there is potential for human error, microbial contamination, and other current technical challenges associated with the manufacture of therapeutic cells.
75 FR 10258 - Notice of a Project Waiver of Section 1605: (Buy American Requirement) of the American Recovery...

Science.gov (United States)

2010-03-05

... recovery by funding current infrastructure construction, not to delay shovel ready projects by requiring... would result in unreasonable delay and thus displace the ``shovel ready'' status for this project...
75 FR 66375 - Notice of a Regional Waiver of Section 1605 (Buy American Requirement) of the American Recovery...

Science.gov (United States)

2010-10-28

... recovery by funding current infrastructure construction, not to delay projects that are already shovel... for DWSRF assistance would result in unreasonable delay and thus displace the ``shovel ready'' status...
Thermal reorientation of hydrogenic Pr3+ centers

International Nuclear Information System (INIS)

Jones, G. D.

1996-01-01

Sets of five multi-hydrogenic centers of both CaF 2 :Pr 3+ and SrF 2 :Pr 3 + show bleaching under selective polarized-light irradiation. Two forms of bleaching behaviour are observed. In reversible polarized bleaching, irradiation creates re-oriented equivalent centers, which can be restored to the original orientation by switching the laser polarization by 90 deg. Indefinite sequences of bleaching and recovery can be established. In photoproduct bleaching, inequivalent centers are produced, which can be reverted by subsequently selectively exciting their absorption lines. Thermal recovery of the bleached centers on warming the crystals occurs abruptly over a 5 K range around 100 K and is noteworthy in occurring at essentially identical temperatures for H - , D - and T - centers. The simplest model for this thermal recovery is thermal activation of the mobile hydrogenic ions over a double well potential barrier. An alternative model proposed by Universitaet Regensburg requires the involvement of high frequency excitations in scattering processes for surmounting the barrier
Cold water immersion recovery following intermittent-sprint exercise in the heat.

Science.gov (United States)

Pointon, Monique; Duffield, Rob; Cannon, Jack; Marino, Frank E

2012-07-01

This study examined the effects of cold water immersion (CWI) on recovery of neuromuscular function following simulated team-sport exercise in the heat. Ten male team-sport athletes performed two sessions of a 2 × 30-min intermittent-sprint exercise (ISE) in 32°C and 52% humidity, followed by a 20-min CWI intervention or passive recovery (CONT) in a randomized, crossover design. The ISE involved a 15-m sprint every minute separated by bouts of hard running, jogging and walking. Voluntary and evoked neuromuscular function, ratings of perceived muscle soreness (MS) and blood markers for muscle damage were measured pre- and post-exercise, immediately post-recovery, 2-h and 24-h post-recovery. Measures of core temperature (Tcore), heart rate (HR), capillary blood and perceptions of exertion, thermal strain and thirst were also recorded at the aforementioned time points. Post-exercise maximal voluntary contraction (MVC) and activation (VA) were reduced in both conditions and remained below pre-exercise values for the 24-h recovery (P recovery period (P recovery rate of reduction in Tcore, HR and MS was enhanced with CWI whilst increasing MVC and VA (P recovery MVC and activation were significantly higher in CONT compared to CWI (P = 0.05). Following exercise in the heat, CWI accelerated the reduction in thermal and cardiovascular load, and improved MVC alongside increased central activation immediately and 2-h post-recovery. However, despite improved acute recovery CWI resulted in an attenuated MVC 24-h post-recovery.
Development and Optimization of Gas-Assisted Gravity Drainage (GAGD) Process for Improved Light Oil Recovery

Energy Technology Data Exchange (ETDEWEB)

Dandina N. Rao; Subhash C. Ayirala; Madhav M. Kulkarni; Wagirin Ruiz Paidin; Thaer N. N. Mahmoud; Daryl S. Sequeira; Amit P. Sharma

2006-09-30

This is the final report describing the evolution of the project ''Development and Optimization of Gas-Assisted Gravity Drainage (GAGD) Process for Improved Light Oil Recovery'' from its conceptual stage in 2002 to the field implementation of the developed technology in 2006. This comprehensive report includes all the experimental research, models developments, analyses of results, salient conclusions and the technology transfer efforts. As planned in the original proposal, the project has been conducted in three separate and concurrent tasks: Task 1 involved a physical model study of the new GAGD process, Task 2 was aimed at further developing the vanishing interfacial tension (VIT) technique for gas-oil miscibility determination, and Task 3 was directed at determining multiphase gas-oil drainage and displacement characteristics in reservoir rocks at realistic pressures and temperatures. The project started with the task of recruiting well-qualified graduate research assistants. After collecting and reviewing the literature on different aspects of the project such gas injection EOR, gravity drainage, miscibility characterization, and gas-oil displacement characteristics in porous media, research plans were developed for the experimental work to be conducted under each of the three tasks. Based on the literature review and dimensional analysis, preliminary criteria were developed for the design of the partially-scaled physical model. Additionally, the need for a separate transparent model for visual observation and verification of the displacement and drainage behavior under gas-assisted gravity drainage was identified. Various materials and methods (ceramic porous material, Stucco, Portland cement, sintered glass beads) were attempted in order to fabricate a satisfactory visual model. In addition to proving the effectiveness of the GAGD process (through measured oil recoveries in the range of 65 to 87% IOIP), the visual models demonstrated
Isothermal recovery rates in shape memory polyurethanes

International Nuclear Information System (INIS)

Azra, Charly; Plummer, Christopher J G; Månson, Jan-Anders E

2011-01-01

This work compares the time dependence of isothermal shape recovery in thermoset and thermoplastic shape memory polyurethanes (SMPUs) with comparable glass transition temperatures. In each case, tensile tests have been used to quantify the influence of various thermo-mechanical programming parameters (deformation temperature, recovery temperature, and stress and storage times following the deformation step) on strain recovery under zero load (free recovery) and stress recovery under fixed strain (constrained recovery). It is shown that the duration of the recovery event may be tuned over several decades of time with an appropriate choice of programming parameters, but that there is a trade-off between the rate of shape recovery and the recoverable stress level. The results are discussed in terms of the thermal characteristics of the SMPUs in the corresponding temperature range as characterized by modulated differential scanning calorimetry and dynamic mechanical analysis, with the emphasis on the role of the effective width of the glass transition temperature and the stability of the network that gives rise to the shape memory effect. (fast track communication)
Supporting Technology for Enhanced Oil Recovery-EOR Thermal Processes Report IV-12

Energy Technology Data Exchange (ETDEWEB)

Izequeido, Alexandor

2001-04-01

This report contains the results of efforts under the six tasks of the Ninth Amendment and Extension of Annex IV, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Agreement. The report is presented in sections (for each of the 6 tasks) and each section contains one or more reports prepared by various individuals or groups describing the results of efforts under each of the tasks. A statement of each task, taken from the agreement, is presented on the first page of each section. The tasks are numbered 62 through 67. The first, second, third, fourth, fifth, sixth, seventh, eight, and ninth reports on Annex IV, [Venezuela MEM/USA-DOE Fossil Energy Report IV-1, IV-2, IV-3, IV-4, IV-5, IV-6, IV-7, and IV-8 (DOE/BETC/SP-83/15, DOE/BC-84/6/SP, DOE/BC-86/2/SP, DOE/BC-87/2/SP, DOE/BC-89/1/SP, DOE/BC-90/1/SP) DOE/BC-92/1/SP, DOE/BC-93/3/SP, and DOE/BC-95/3/SP] contain the results from the first 61 tasks. Those reports are dated April 1983, August 1984, March 1986, July 1! 987, November 1988, December 1989, October 1991, February 1993, and March 1995 respectively.
Floor Heating with Displacement Ventilation: An Experimental and Numerical Analysis

DEFF Research Database (Denmark)

Causone, Francesco; Olesen, Bjarne W.; Corgnati, S.P.

2010-01-01

The effect of floor heating combined with displacement ventilation (DV) on thermal indoor environments and indoor air quality (IAQ) was studied by means of CFD. The numerical model was validated with experimental data. A typical office room was simulated, and one of the occupants was considered...... to simulate different kinds of contaminant sources, under the same boundary conditions. It was found that DV does not guarantee a better IAQ than full mixing when contaminant sources are not linked to heat sources, even when floor heating is used. Contaminants produced by powerful heat sources require high...
The use of a displacement device negatively affects the performance of dogs (Canis familiaris) in visible object displacement tasks.

Science.gov (United States)

Müller, Corsin A; Riemer, Stefanie; Range, Friederike; Huber, Ludwig

2014-08-01

Visible and invisible displacement tasks have been used widely for comparative studies of animals' understanding of object permanence, with evidence accumulating that some species can solve invisible displacement tasks and, thus, reach Piagetian stage 6 of object permanence. In contrast, dogs appear to rely on associative cues, such as the location of the displacement device, during invisible displacement tasks. It remains unclear, however, whether dogs, and other species that failed in invisible displacement tasks, do so because of their inability to form a mental representation of the target object, or simply because of the involvement of a more salient but potentially misleading associative cue, the displacement device. Here we show that the use of a displacement device impairs the performance of dogs also in visible displacement tasks: their search accuracy was significantly lower when a visible displacement was performed with a displacement device, and only two of initially 42 dogs passed the sham-baiting control conditions. The negative influence of the displacement device in visible displacement tasks may be explained by strong associative cues overriding explicit information about the target object's location, reminiscent of an overshadowing effect, and/or object individuation errors as the target object is placed within the displacement device and moves along a spatiotemporally identical trajectory. Our data suggest that a comprehensive appraisal of a species' performance in object permanence tasks should include visible displacement tasks with the same displacement device used in invisible displacements, which typically has not been done in the past.
Displacement data assimilation

Energy Technology Data Exchange (ETDEWEB)

Rosenthal, W. Steven [Pacific Northwest Laboratory, Richland, WA 99354 (United States); Venkataramani, Shankar [Department of Mathematics and Program in Applied Mathematics, University of Arizona, Tucson, AZ 85721 (United States); Mariano, Arthur J. [Rosenstiel School of Marine & Atmospheric Science, University of Miami, Miami, FL 33149 (United States); Restrepo, Juan M., E-mail: restrepo@math.oregonstate.edu [Department of Mathematics, Oregon State University, Corvallis, OR 97331 (United States)

2017-02-01

We show that modifying a Bayesian data assimilation scheme by incorporating kinematically-consistent displacement corrections produces a scheme that is demonstrably better at estimating partially observed state vectors in a setting where feature information is important. While the displacement transformation is generic, here we implement it within an ensemble Kalman Filter framework and demonstrate its effectiveness in tracking stochastically perturbed vortices.
Mathematical models utilized in the retrieval of displacement information encoded in fringe patterns

Science.gov (United States)

Sciammarella, Cesar A.; Lamberti, Luciano

2016-02-01

All the techniques that measure displacements, whether in the range of visible optics or any other form of field methods, require the presence of a carrier signal. A carrier signal is a wave form modulated (modified) by an input, deformation of the medium. A carrier is tagged to the medium under analysis and deforms with the medium. The wave form must be known both in the unmodulated and the modulated conditions. There are two basic mathematical models that can be utilized to decode the information contained in the carrier, phase modulation or frequency modulation, both are closely connected. Basic problems connected to the detection and recovery of displacement information that are common to all optical techniques will be analyzed in this paper, focusing on the general theory common to all the methods independently of the type of signal utilized. The aspects discussed are those that have practical impact in the process of data gathering and data processing.

Vertical Displacements Driven by Groundwater Storage Changes in the North China Plain Detected by GPS Observations

Directory of Open Access Journals (Sweden)

Renli Liu

2018-02-01

Full Text Available The North China Plain (NCP has been experiencing the most severe groundwater depletion in China, leading to a broad region of vertical motions of the Earth’s surface. This paper explores the seasonal and linear trend variations of surface vertical displacements caused by the groundwater changes in NCP from 2009 to 2013 using Global Positioning System (GPS and Gravity Recovery and Climate Experiment (GRACE techniques. Results show that the peak-to-peak amplitude of GPS-derived annual variation is about 3.7~6.0 mm and is highly correlated (R > 0.6 for most selected GPS stations with results from GRACE, which would confirm that the vertical displacements of continuous GPS (CGPS stations are mainly caused by groundwater storage (GWS changes in NCP, since GWS is the dominant component of total water storage (TWS anomalies in this area. The linear trends of selected bedrock-located IGS CGPS stations reveal the distinct GWS changes in period of 2009–2010 (decrease and 2011–2013 (rebound, which are consistent with results from GRACE-derived GWS anomalies and in situ GWS observations. This result implies that the rate of groundwater depletion in NCP has slowed in recent years. The impacts of geological condition (bedrock or sediment of CGPS stations to their results are also investigated in this study. Contrasted with the slight linear rates (−0.69~1.5 mm/a of bedrock-located CGPS stations, the linear rates of sediment-located CGPS stations are between −44 mm/a and −17 mm/a. It is due to the opposite vertical displacements induced by the Earth surface’s porous and elastic response to groundwater depletion. Besides, the distinct renewal characteristics of shallow and deep groundwater in NCP are discussed. The GPS-based vertical displacement time series, to some extent, can reflect the quicker recovery of shallow unconfined groundwater than the deep confined groundwater in NCP; through one month earlier to attain the maximum height for CGPS
Finite element modelling and experimental characterization of an electro-thermally actuated silicon-polymer micro gripper

International Nuclear Information System (INIS)

Krecinic, F; Duc, T Chu; Sarro, P M; Lau, G K

2008-01-01

This paper presents simulation and experimental characterization of an electro-thermally actuated micro gripper. This micro actuator can conceptually be seen as a bi-morph structure of SU-8 and silicon, actuated by thermal expansion of the polymer. The polymer micro gripper with an embedded comb-like silicon skeleton is designed to reduce unwanted out-of-plane bending of the actuator, while offering a large gripper stroke. The temperature and displacement field of the micro gripper structure is determined using a two-dimensional finite element analysis. This analysis is compared to experimental data from steady-state and transient measurements of the integrated heater resistance, which depends on the average temperature of the actuator. The stability of the polymer actuator is evaluated by recording the transient behaviour of the actual jaw displacements. The maximum single jaw displacement of this micro gripper design is 34 µm at a driving voltage of 4 V and an average actuator temperature of 170 °C. The transient thermal response is modelled by a first-order system with a characteristic time constant of 11.1 ms. The simulated force capability of the device is 0.57 mN per µm jaw displacement
Polydyne displacement interferometer using frequency-modulated light

Science.gov (United States)

Arablu, Masoud; Smith, Stuart T.

2018-05-01

A radio-frequency Frequency-Modulated (FM) signal is used to diffract a He-Ne laser beam through an Acousto-Optic Modulator (AOM). Due to the modulation of the FM signal, the measured spectra of the diffracted beams comprise a series of phase-synchronized harmonics that have exact integer frequency separation. The first diffraction side-beam emerging from the AOM is selected by a slit to be used in a polydyne displacement interferometer in a Michelson interferometer topology. The displacement measurement is derived from the phase measurement of selected modulation harmonic pairs. Individual harmonic frequency amplitudes are measured using discrete Fourier transform applied to the signal from a single photodetector. Phase signals are derived from the changes in the amplitudes of different harmonic pairs (typically odd-even pairs) with the phase being extracted using a standard quadrature method. In this study, two different modulation frequencies of 5 and 10 kHz are used at different modulation depths. The measured displacements by different harmonic pairs are compared with a commercial heterodyne interferometer being used as a reference for these studies. Measurements obtained from five different harmonic pairs when the moving mirror of the interferometer is scanned over ranges up to 10 μm all show differences of less than 50 nm from the reference interferometer measurements. A drift test was also used to evaluate the differences between the polydyne interferometer and reference measurements that had different optical path lengths of approximately 25 mm and 50 mm, respectively. The drift test results indicate that about half of the differences can be attributed to temperature, pressure, and humidity variations. Other influences include Abbe and thermal expansion effects. Rough magnitude estimates using simple models for these two effects can account for remaining observed deviations.
Displacement cascades in diatomic materials

International Nuclear Information System (INIS)

Parkin, D.M.; Coulter, C.A.

1981-01-01

A new function, the specified-projectile displacement function p/sub ijk/ (E), is introduced to describe displacement cascades in polyatomic materials. This function describes the specific collision events that produce displacements and hence adds new information not previously available. Calculations of p/sub ijk/ (E) for MgO, Al 2 O 3 and TaO are presented and discussed. Results show that the parameters that have the largest effect on displacement collision events are the PKA energy and the mass ratio of the atom types in the material. It is further shown that the microscopic nature of the displacement events changes over the entire recoil energy range relevant to fusion neutron spectra and that these changes are different in materials whose mass ratio is near one than in those where it is far from one
DEVELOPMENT OF BIOSURFACTANT-MEDIATED OIL RECOVERY IN MODEL POROUS SYSTEMS AND COMPUTER SIMULATIONS OF BIOSURFACTANT-MEDIATED OIL RECOVERY

Energy Technology Data Exchange (ETDEWEB)

M.J. McInerney; S.K. Maudgalya; R. Knapp; M. Folmsbee

2004-05-31

Current technology recovers only one-third to one-half of the oil that is originally present in an oil reservoir. Entrapment of petroleum hydrocarbons by capillary forces is a major factor that limits oil recovery (1, 3, 4). Hydrocarbon displacement can occur if interfacial tension (IFT) between the hydrocarbon and aqueous phases is reduced by several orders of magnitude. Microbially-produced biosurfactants may be an economical method to recover residual hydrocarbons since they are effective at low concentrations. Previously, we showed that substantial mobilization of residual hydrocarbon from a model porous system occurs at biosurfactant concentrations made naturally by B. mojavensis strain JF-1 if a polymer and 2,3-butanediol were present (2). In this report, we include data on oil recovery from Berea sandstone experiments along with our previous data from sand pack columns in order to relate biosurfactant concentration to the fraction of oil recovered. We also investigate the effect that the JF-2 biosurfactant has on interfacial tension (IFT). The presence of a co-surfactant, 2,3-butanediol, was shown to improve oil recoveries possibly by changing the optimal salinity concentration of the formulation. The JF-2 biosurfactant lowered IFT by nearly 2 orders of magnitude compared to typical values of 28-29 mN/m. Increasing the salinity increased the IFT with or without 2,3-butanediol present. The lowest interfacial tension observed was 0.1 mN/m. Tertiary oil recovery experiments showed that biosurfactant solutions with concentrations ranging from 10 to 60 mg/l in the presence of 0.1 mM 2,3-butanediol and 1 g/l of partially hydrolyzed polyacrylamide (PHPA) recovered 10-40% of the residual oil present in Berea sandstone cores. When PHPA was used alone, about 10% of the residual oil was recovered. Thus, about 10% of the residual oil recovered in these experiments was due to the increase in viscosity of the displacing fluid. Little or no oil was recovered at
Oil recovery enhancement from fractured, low permeability reservoirs. Part 2, Annual report, October 1, 1990--September 31, 1991

Energy Technology Data Exchange (ETDEWEB)

Poston, S.W.

1991-12-31

The results of the investigative efforts for this jointly funded DOE-State of Texas research project achieved during the 1990--1991 year may be summarized as follows: Geological Characterization -- Detailed maps of the development and hierarchical nature the fracture system exhibited by Austin Chalk outcrops were prepared. These results of these efforts were directly applied to the development of production decline type curves applicable to a dual fracture-matrix flow system. Analysis of production records obtained from Austin Chalk operators illustrated the utility of these type curves to determine relative fracture/matrix contributions and extent. Well-log response in Austin Chalk wells has been shown to be a reliable indicator of organic maturity. (VSP) Vertical-Seismic Profile data was used to use shear-wave splitting concepts to estimate fracture orientations. Several programs were to be written to facilitate analysis of the data. The results of these efforts indicated fractures could be detected with VSP seismic methods. Development of the (EOR) Enhanced Oil Recovery Imbibition Process -- Laboratory displacement as well as MRI and CT imaging studies have shown the carbonated water-imbibition displacement process significantly accelerates and increases recovery of an oil saturated, low permeability core material, when compared to that of a normal brine imbibition displacement process. A study of oil recovery by the application of a cyclic carbonated water imbibition process, followed by reducing the pressure below the bubble point of the CO{sub 2}-water solution, indicated the possibility of alternate and new enhanced recovery method. The installation of an artificial solution gas drive significantly increased oil recovery. The extent and arrangement of micro-fractures in Austin Chalk horizontal cores was mapped with CT scanning techniques. The degree of interconnection of the micro-fractures was easily visualized.
Interactions between displacement cascades and Σ3〈110〉 tilt grain boundaries in Cu

Energy Technology Data Exchange (ETDEWEB)

Li, Bo [CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, Anhui, 230027 (China); The Peac Institute of Multiscale Sciences, Chengdu, Sichuan, 610031 (China); Long, Xiao-Jiang [The Peac Institute of Multiscale Sciences, Chengdu, Sichuan, 610031 (China); College of Physical Science and Technology, Sichuan University, Chengdu, Sichuan, 610064 (China); Shen, Zhao-Wu, E-mail: ZWShen@ustc.edu.cn [CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, Anhui, 230027 (China); Luo, Sheng-Nian, E-mail: sluo@pims.ac.cn [Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu, Sichuan, 610031 (China); The Peac Institute of Multiscale Sciences, Chengdu, Sichuan, 610031 (China)

2016-12-01

With large-scale molecular dynamics simulations, we investigate systematically the interaction of displacement cascades with a set of Σ3〈110〉 tilt grain boundaries (GBs) in Cu bicrystals at low ambient temperatures, as regards irradiation-induced defect production/absorption and GB migration/faceting. Except for coherent twin boundary, GBs exhibit pronounced preferential absorption of interstitials, which depends on initial primary knock-on atom distance from GB plane and inclination angle. GB migration occurs when displacement cascades overlap with a GB plane, as induced by recrystallization of thermal spike, and concurrent asymmetric grain growth. Faceting occurs via expanding coherent twin boundaries for asymmetric GBs.
Dynamic recovery in nanocrystalline Ni

International Nuclear Information System (INIS)

Sun, Z.; Van Petegem, S.; Cervellino, A.; Durst, K.; Blum, W.; Van Swygenhoven, H.

2015-01-01

The constant flow stress reached during uniaxial deformation of electrodeposited nanocrystalline Ni reflects a quasi-stationary balance between dislocation slip and grain boundary (GB) accommodation mechanisms. Stress reduction tests allow to suppress dislocation slip and bring recovery mechanisms into the foreground. When combined with in situ X-ray diffraction it can be shown that grain boundary recovery mechanisms play an important role in producing plastic strain while hardening the microstructure. This result has a significant consequence for the parameters of thermally activated glide of dislocations, such as athermal stress and activation volume, which are traditionally derived from stress/strain rate change tests
1D Simulations for Microbial Enhanced Oil Recovery with Metabolite Partitioning

DEFF Research Database (Denmark)

Nielsen, Sidsel Marie; Shapiro, Alexander; Michelsen, Michael Locht

2010-01-01

We have developed a mathematical model describing the process of microbial enhanced oil recovery (MEOR). The one-dimensional isothermal model comprises displacement of oil bywater containing bacteria and substrate for their feeding. The bacterial products are both bacteria andmetabolites....... The characteristics for the water phase saturation profiles and the oil recovery curves are elucidated. However, the effect from the surfactant is not necessarily restricted to influence only interfacial tension, but it can also be an approach for changing, e.g., wettability. The distribution coefficient determines...... the time lag, until residual oil mobilization is initialized. It has also been found that the final recovery depends on the distance from the inlet before the surfactant effect takes place. The surfactant effect position is sensitive to changes in maximum growth rate, and injection concentrations...
One-dimensional modeling of thermal energy produced in a seismic fault

Science.gov (United States)

Konga, Guy Pascal; Koumetio, Fidèle; Yemele, David; Olivier Djiogang, Francis

2017-12-01

Generally, one observes an anomaly of temperature before a big earthquake. In this paper, we established the expression of thermal energy produced by friction forces between the walls of a seismic fault while considering the dynamic of a one-dimensional spring-block model. It is noted that, before the rupture of a seismic fault, displacements are caused by microseisms. The curves of variation of this thermal energy with time show that, for oscillatory and aperiodic displacement, the thermal energy is accumulated in the same way. The study reveals that thermal energy as well as temperature increases abruptly after a certain amount of time. We suggest that the corresponding time is the start of the anomaly of temperature observed which can be considered as precursory effect of a big seism. We suggest that the thermal energy can heat gases and dilate rocks until they crack. The warm gases can then pass through the cracks towards the surface. The cracks created by thermal energy can also contribute to the rupture of the seismic fault. We also suggest that the theoretical model of thermal energy, produced in seismic fault, associated with a large quantity of experimental data may help in the prediction of earthquakes.
Control performances of a piezoactuator direct drive valve system at high temperatures with thermal insulation

Science.gov (United States)

Han, Yung-Min; Han, Chulhee; Kim, Wan Ho; Seong, Ho Yong; Choi, Seung-Bok

2016-09-01

This technical note presents control performances of a piezoactuator direct drive valve (PDDV) operated at high temperature environment. After briefly discussing operating principle and mechanical dimensions of the proposed PDDV, an appropriate size of the PDDV is manufactured. As a first step, the temperature effect on the valve performance is experimentally investigated by measuring the spool displacement at various temperatures. Subsequently, the PDDV is thermally insulated using aerogel and installed in a large-size heat chamber in which the pneumatic-hydraulic cylinders and sensors are equipped. A proportional-integral-derivative feedback controller is then designed and implemented to control the spool displacement of the valve system. In this work, the spool displacement is chosen as a control variable since it is directly related to the flow rate of the valve system. Three different sinusoidal displacements with different frequencies of 1, 10 and 50 Hz are used as reference spool displacement and tracking controls are undertaken up to 150 °C. It is shown that the proposed PDDV with the thermal insulation can provide favorable control responses without significant tracking errors at high temperatures.
Modelling toehold-mediated RNA strand displacement.

Science.gov (United States)

Šulc, Petr; Ouldridge, Thomas E; Romano, Flavio; Doye, Jonathan P K; Louis, Ard A

2015-03-10

We study the thermodynamics and kinetics of an RNA toehold-mediated strand displacement reaction with a recently developed coarse-grained model of RNA. Strand displacement, during which a single strand displaces a different strand previously bound to a complementary substrate strand, is an essential mechanism in active nucleic acid nanotechnology and has also been hypothesized to occur in vivo. We study the rate of displacement reactions as a function of the length of the toehold and temperature and make two experimentally testable predictions: that the displacement is faster if the toehold is placed at the 5' end of the substrate; and that the displacement slows down with increasing temperature for longer toeholds. Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.
Recent developments in numerical simulation techniques of thermal recovery processes

Energy Technology Data Exchange (ETDEWEB)

Tamim, M. [Bangladesh University of Engineering and Technology, Bangladesh (Bangladesh); Abou-Kassem, J.H. [Chemical and Petroleum Engineering Department, UAE University, Al-Ain 17555 (United Arab Emirates); Farouq Ali, S.M. [University of Alberta, Alberta (Canada)

2000-05-01

Numerical simulation of thermal processes (steam flooding, steam stimulation, SAGD, in-situ combustion, electrical heating, etc.) is an integral part of a thermal project design. The general tendency in the last 10 years has been to use commercial simulators. During the last decade, only a few new models have been reported in the literature. More work has been done to modify and refine solutions to existing problems to improve the efficiency of simulators. The paper discusses some of the recent developments in simulation techniques of thermal processes such as grid refinement, grid orientation, effect of temperature on relative permeability, mathematical models, and solution methods. The various aspects of simulation discussed here promote better understanding of the problems encountered in the simulation of thermal processes and will be of value to both simulator users and developers.
Pulsational stabilities of a star in thermal imbalance: comparison between the methods

International Nuclear Information System (INIS)

Vemury, S.K.

1978-01-01

The stability coefficients for quasi-adiabatic pulsations for a model in thermal imbalance are evaluated using the dynamical energy (DE) approach, the total (kinetic plus potential) energy (TE) approach, and the small amplitude (SA) approaches. From a comparison among the methods, it is found that there can exist two distinct stability coefficients under conditions of thermal imbalance as pointed out by Demaret. It is shown that both the TE approaches lead to one stability coefficient, while both the SA approaches lead to another coefficient. The coefficient obtained through the energy approaches is identified as the one which determines the stability of the velocity amplitudes.For a prenova model with a thin hydrogen-burning shell in thermal imbalance, several radial modes are found to be unstable both for radial displacements and for velocity amplitudes. However, a new kind of pulsational instability also appears, viz., while the radial displacements are unstable, the velocity amplitudes may be stabilized through the thermal imbalance terms
MRI of displaced meniscal fragments

International Nuclear Information System (INIS)

Dunoski, Brian; Zbojniewicz, Andrew M.; Laor, Tal

2012-01-01

A torn meniscus frequently requires surgical fixation or debridement as definitive treatment. Meniscal tears with associated fragment displacement, such as bucket handle and flap tears, can be difficult to recognize and accurately describe on MRI, and displaced fragments can be challenging to identify at surgery. A displaced meniscal fragment can be obscured by synovium or be in a location not usually evaluated at arthroscopy. We present a pictorial essay of meniscal tears with displaced fragments in patients referred to a pediatric hospital in order to increase recognition and accurate interpretation by the radiologist, who in turn can help assist the surgeon in planning appropriate therapy. (orig.)
MRI of displaced meniscal fragments

Energy Technology Data Exchange (ETDEWEB)

Dunoski, Brian [University of Cincinnati College of Medicine, Department of Radiology, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States); Children' s Hospital of Michigan, Department of Radiology, Detroit, MI (United States); Zbojniewicz, Andrew M.; Laor, Tal [University of Cincinnati College of Medicine, Department of Radiology, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States)

2012-01-15

A torn meniscus frequently requires surgical fixation or debridement as definitive treatment. Meniscal tears with associated fragment displacement, such as bucket handle and flap tears, can be difficult to recognize and accurately describe on MRI, and displaced fragments can be challenging to identify at surgery. A displaced meniscal fragment can be obscured by synovium or be in a location not usually evaluated at arthroscopy. We present a pictorial essay of meniscal tears with displaced fragments in patients referred to a pediatric hospital in order to increase recognition and accurate interpretation by the radiologist, who in turn can help assist the surgeon in planning appropriate therapy. (orig.)
Variation in thermal sensitivity and thermal tolerances in an invasive species across a climatic gradient: lessons from the land snail Cornu aspersum.

Directory of Open Access Journals (Sweden)

Juan Diego Gaitán-Espitia

Full Text Available The ability of organisms to perform at different temperatures could be described by a continuous nonlinear reaction norm (i.e., thermal performance curve, TPC, in which the phenotypic trait value varies as a function of temperature. Almost any shift in the parameters of this performance curve could highlight the direct effect of temperature on organism fitness, providing a powerful framework for testing thermal adaptation hypotheses. Inter-and intraspecific differences in this performance curve are also reflected in thermal tolerances limits (e.g., critical and lethal limits, influencing the biogeographic patterns of species' distribution. Within this context, here we investigated the intraspecific variation in thermal sensitivities and thermal tolerances in three populations of the invasive snail Cornu aspersum across a geographical gradient, characterized by different climatic conditions. Thus, we examined population differentiation in the TPCs, thermal-coma recovery times, expression of heat-shock proteins and standard metabolic rate (i.e., energetic costs of physiological differentiation. We tested two competing hypotheses regarding thermal adaptation (the "hotter is better" and the generalist-specialist trade-offs. Our results show that the differences in thermal sensitivity among populations of C. aspersum follow a latitudinal pattern, which is likely the result of a combination of thermodynamic constraints ("hotter is better" and thermal adaptations to their local environments (generalist-specialist trade-offs. This finding is also consistent with some thermal tolerance indices such as the Heat-Shock Protein Response and the recovery time from chill-coma. However, mixed responses in the evaluated traits suggest that thermal adaptation in this species is not complete, as we were not able to detect any differences in neither energetic costs of physiological differentiation among populations, nor in the heat-coma recovery.
Effects of threshold displacement energy on defect production by displacement cascades in α, β and γ-LiAlO2

International Nuclear Information System (INIS)

Tsuchihira, H.; Oda, T.; Tanaka, S.

2013-01-01

Threshold displacement energy evaluation and a series of displacement cascade simulations in α, β, and γ-LiAlO 2 were performed using molecular dynamics. Threshold displacement energy evaluations indicated that higher absolute ionic charge values and larger densities both increase threshold displacement energy. The displacement cascade simulations suggest that the influence of different crystal structures on the number of interstitial atoms generated in a displacement cascade is explainable almost entirely by the difference of the threshold displacement energy
Effect of displaced versus non-displaced pelvic fractures on long-term racing performance in 31 Thoroughbred racehorses.

Science.gov (United States)

Hennessy, S E; Muurlink, M A; Anderson, G A; Puksmann, T N; Whitton, R C

2013-06-01

To evaluate the long-term racing prognosis for Thoroughbred racehorses with displaced versus non-displaced fractures of the pelvis identified by scintigraphy. Retrospective case analysis. Medical records of 31 Thoroughbred racehorses presenting to the University of Melbourne Equine Centre with fractures of the pelvis that were identified by scintigraphy were reviewed. Pelvic fracture site was determined and defined as displaced or non-displaced based on ultrasound and/or radiographic findings. Race records were analysed for each horse, with a minimum of 24 months' follow-up, and correlated with fracture type to determine long-term prognosis for racing. Results are expressed as median and range. Fractures at a single site were more common (n = 22) than fractures involving two sites (n = 9) and the ilial wing was the most commonly affected (n = 12). Thoroughbred racehorses with displaced pelvic fractures at any site (n = 12) raced fewer times within 24 months of diagnosis than horses with non-displaced fractures (n = 19) (median 0.5, range 0-13 vs 7, 0-24; P = 0.037), but there was no clear statistical difference in race earnings between the two groups (median A$0, range A$0-$123,250 vs A$14,440, A$0-$325,500, respectively; P = 0.080). Four horses with displaced fractures (33%) were euthanased on humane grounds because of persistent severe pain. When these horses were excluded from the analysis, there were no differences in performance variables between horses with a displaced or non-displaced pelvic fracture. Thoroughbred racehorses with a displaced or non-displaced pelvic fracture that survive the initial post-injury period have a good prognosis for racing. © 2013 The Authors. Australian Veterinary Journal © 2013 Australian Veterinary Association.
Influence of solder joint length to the mechanical aspect during the thermal stress analysis

Science.gov (United States)

Tan, J. S.; Khor, C. Y.; Rahim, Wan Mohd Faizal Wan Abd; Ishak, Muhammad Ikman; Rosli, M. U.; Jamalludin, Mohd Riduan; Zakaria, M. S.; Nawi, M. A. M.; Aziz, M. S. Abdul; Ani, F. Che

2017-09-01

Solder joint is an important interconnector in surface mount technology (SMT) assembly process. The real time stress, strain and displacement of the solder joint is difficult to observe and assess the experiment. To tackle these problems, simulation analysis was employed to study the von Mises stress, strain and displacement in the thermal stress analysis by using Finite element based software. In this study, a model of leadless electronic package was considered. The thermal stress analysis was performed to investigate the effect of the solder length to those mechanical aspects. The simulation results revealed that solder length gives significant effect to the maximum von Mises stress to the solder joint. Besides, changes in solder length also influence the displacement of the solder joint in the thermal environment. The increment of the solder length significantly reduces the von Mises stress and strain on the solder joint. Thus, the understanding of the physical parameter for solder joint is important for engineer prior to designing the solder joint of the electronic component.

Fundamentals of displacement production in irradiated metals

International Nuclear Information System (INIS)

Doran, D.G.

1975-09-01

Radioinduced displacement damage in metals is described. Discussions are included on the displacement event itself, calculation of displacement rates in general, the manner in which different types of radiation interact with metals to produce displacements, the similarities and differences in the types of damage produced, the current status of computer simulations of displacement cascades, experimental evidence regarding cascades, and aspects of correlating damage produced by different types of radiation
Modelling Toehold-Mediated RNA Strand Displacement

OpenAIRE

Šulc, Petr; Ouldridge, Thomas E.; Romano, Flavio; Doye, Jonathan P.K.; Louis, Ard A.

2015-01-01

We study the thermodynamics and kinetics of an RNA toehold-mediated strand displacement reaction with a recently developed coarse-grained model of RNA. Strand displacement, during which a single strand displaces a different strand previously bound to a complementary substrate strand, is an essential mechanism in active nucleic acid nanotechnology and has also been hypothesized to occur in vivo. We study the rate of displacement reactions as a function of the length of the toehold and temperat...
Measurement of interfacial displacement of a liquid film in microchannels using laser focus displacement meter

International Nuclear Information System (INIS)

Hazuku, Tatsuya; Fukamachi, Norihiro; Takamasa, Tomoji; Hibiki, Takashi

2004-01-01

This paper presents a new method for measuring the interfacial displacement of a liquid film in microchannels using a laser focus displacement meter (LFD). The purpose of the study is to clarify the effectiveness of the new method for obtaining detailed information concerning interfacial displacement, especially in the case of a thin liquid film, in micro- and mini-channels. To prevent the tube wall signal from disturbing that of the gas-liquid interface, a fluorocarbon tube with water box was used; the refraction index of this device is same as that for water. With this method, accurate instantaneous measurements of interfacial displacement of the liquid film were achieved. The error caused by refraction of the laser beam passing through the acrylic water box and fluorocarbon tube was estimated analytically and experimentally. The formulated analytical equation can estimate the real interface displacement using measured displacement in a fluorocarbon tube of 25 μm to 2.0 mm I.D. A preliminary test using fluorocarbon tubes of 1 and 2 mm I.D. showed that the corrected interface displacement calculated by the equation agreed with real displacement within a 1% margin of error. It was also confirmed that the LFD in the system could measure a liquid film of 0.25 μm at the thinnest. We made simultaneous measurements of the interface in fluorocarbon tubes of 0.5 and 1 mm I.D. using the LFD and a high-speed video camera with a microscope. These showed that the LFD could measure the interface of a liquid film with high spatial and temporal resolution during annular, slug, and piston flow regimes. The data also clarified the existence of a thin liquid film less than 1 μm in thickness in slug and annular flow regions. (author)
Condensate recovery by cycling at declining pressures

Energy Technology Data Exchange (ETDEWEB)

Havlena, Z G; Griffith, J D; Pot, R; Kiel, O G

1967-06-05

Cycling condensate reservoirs under conditions of declining pressure, rather than constant pressure, is advantageous from both a recovery and an economic standpoint. Wet gas displaced from the swept areas is recovered concurrently with wet gas recovered by gas expansion from the unswept portions of the reservoir. Any liquid condensed in the swept areas is revaporized by dry injection gas and recovered as an enriched gas. By this mode of operation, high condensate recovery is obtained, gas sales may be possible at an earlier stage of depletion, more flexibility in field and plant operations is feasible and reduction of 15% in investment and operating costs is achieved. Injection gas requirements are reduced by 40%. The Windfall reservoir in Canada has been successfully produced in this manner, starting in 1962. It is a typical retrograde type reservoir which in 1965 represented 15% of reservoirs exploited in North America.
Efficiency of two-step solar thermochemical non-stoichiometric redox cycles with heat recovery

International Nuclear Information System (INIS)

Lapp, J.; Davidson, J.H.; Lipiński, W.

2012-01-01

Improvements in the effectiveness of solid phase heat recovery and in the thermodynamic properties of metal oxides are the most important paths to achieving unprecedented thermal efficiencies of 10% and higher in non-stoichiometric solar redox reactors. In this paper, the impact of solid and gas phase heat recovery on the efficiency of a non-stoichiometric cerium dioxide-based H 2 O/CO 2 splitting cycle realized in a solar-driven reactor are evaluated in a parametric thermodynamic analysis. Application of solid phase heat recovery to the cycling metal oxide allows for lower reduction zone operating temperatures, simplifying reactor design. An optimum temperature for metal oxide reduction results from two competing phenomena as the reduction temperature is increased: increasing re-radiation losses from the reactor aperture and decreasing heat loss due to imperfect solid phase heat recovery. Additionally, solid phase heat recovery increases the efficiency gains made possible by gas phase heat recovery. -- Highlights: ► Both solid and gas phase heat recovery are essential to achieve high thermal efficiency in non-stoichiometric ceria-based solar redox reactors. ► Solid phase heat recovery allows for lower reduction temperatures and increases the gains made possible by gas phase heat recovery. ► The optimum reduction temperature increases with increasing concentration ratio and decreasing solid phase heat recovery effectiveness. ► Even moderate levels of heat recovery dramatically improve reactor efficiency from 3.5% to 16%.
Potential use of California lignite and other alternate fuel for enhanced oil recovery. Phase I and II. Final report. [As alternative fuels for steam generation in thermal EOR

Energy Technology Data Exchange (ETDEWEB)

Shelton, R.; Shimizu, A.; Briggs, A.

1980-02-01

The Nation's continued reliance on liquid fossil fuels and decreasing reserves of light oils gives increased impetus to improving the recovery of heavy oil. Thermal enhanced oil recovery EOR techniques, such as steam injection, have generally been the most effective for increasing heavy oil production. However, conventional steam generation consumes a large fraction of the produced oil. The substitution of alternate (solid) fuels would release much of this consumed oil to market. This two-part report focuses on two solid fuels available in California, the site of most thermal EOR - petroleum coke and lignite. Phase I, entitled Economic Analysis, shows detailed cost comparisons between the two candidate fuels and also with Western coal. The analysis includes fuels characterizations, process designs for several combustion systems, and a thorough evaluation of the technical and economic uncertainties. In Phase II, many technical parameters of petroleum coke combustion were measured in a pilot-plant fluidized bed. The results of the study showed that petroleum coke combustion for EOR is feasible and cost effective in a fluidized bed combustor.
Modeling thermal spike driven reactions at low temperature and application to zirconium carbide radiation damage

Science.gov (United States)

Ulmer, Christopher J.; Motta, Arthur T.

2017-11-01

The development of TEM-visible damage in materials under irradiation at cryogenic temperatures cannot be explained using classical rate theory modeling with thermally activated reactions since at low temperatures thermal reaction rates are too low. Although point defect mobility approaches zero at low temperature, the thermal spikes induced by displacement cascades enable some atom mobility as it cools. In this work a model is developed to calculate "athermal" reaction rates from the atomic mobility within the irradiation-induced thermal spikes, including both displacement cascades and electronic stopping. The athermal reaction rates are added to a simple rate theory cluster dynamics model to allow for the simulation of microstructure evolution during irradiation at cryogenic temperatures. The rate theory model is applied to in-situ irradiation of ZrC and compares well at cryogenic temperatures. The results show that the addition of the thermal spike model makes it possible to rationalize microstructure evolution in the low temperature regime.
Mechanical and thermal measurements on a 11 m long beam screen in the LHC Magnet Test String during RUN 3A

CERN Document Server

Artoos, K; Kos, N

1999-01-01

Two eleven meter long beam screens were installed in the third dipole of the LHC Magnet Test String. Instrumentation was used to measure the mechanical and thermal behaviour of the screens during thermal transients and quenches. The horizontal deformation, angular displacement, heating of the screen as a result of the quench induced eddy currents and relative longitudinal displacement between beam screen and magnet end were measured.
Displacement functions for diatomic materials

International Nuclear Information System (INIS)

Panrkin, D.M.; Coulter, C.A.

1979-01-01

An extension of the methods of Lindhard et at. was used to calculate the total displacement function n/sub ij/(E) for a number of diatomic materials, where n/sub ij/(E) is defined to be the average number of atoms of type j which are displaced from their sites in a displacement cascade initiated by a PKA of type i and energy E. From the n/sub ij/(E) one can calculate the fraction n/sub ij/(E) of the displacements produced by a type i PKA with energy E which are of type j. Values of the n/sub ij/ for MgO, CaO, Al 2 O 3 , and TaO are presented. It is shown that for diatomic materials with mass ratios reasonably near one (e.g., MgO, Al 2 O 3 ) and equal displacement thresholds for the two species the n/sub ij/ become independent of the PKA type i at energies only a few times threshold. However, for larger mass ratios the n/sub ij/ do not become independent of i until much larger, energies are reached - e.g. > 10 5 eV for TaO. In addition, it is found that the n/sub ij/ depend sensitively on the displacement thresholds, with very dramatic charges occuring when the two thresholds become significantly different from one another
Fine Formation During Brine-Crude Oil-Calcite Interaction in Smart Water Enhanced Oil Recovery for Caspian Carbonates

DEFF Research Database (Denmark)

Chakravarty, Krishna Hara; Fosbøl, Philip Loldrup; Thomsen, Kaj

2015-01-01

Modified sea water has been shown to affect the oil recovery fraction considerably during secondary and tertiary waterfloods. Available soluble potential ions (i.e. Ca2+, Mg2+ & SO42-) in the interacting waterflood (ITW) are suggested to play a key role in increasing the displacement efficiency...... of oil. In previous studies, compositions of injected waterfloods (IJW) have been correlated to the observed oil recovery. This study highlights differences between IJW and ITW for different studies reported in literature....
Etiopathogenesis of abomasal displacement in cattle

Directory of Open Access Journals (Sweden)

Šamanc Horea

2003-01-01

Full Text Available Abomasal displacement presents topographic gastropathy, where this organ has changed its position, and there is simultaneous dilatation which can vary in intensity. The incidence of this disorder in herds of high-yield dairy cows varies to a great degree (1 to 18 %. Abomasal displacement was established in herds of East-Frisian cows in 1 to 3% animals, and in Holstein cow herds in 5 to 18 % animals. The most frequent abomasal displacement is to the left (88%. There is significant seasonal variation in the incidence of abomasal displacement. About two-thirds of cases of abomasal displacement are diagnosed from October until April. The disorder appears more frequently in cows with repeated lactations. It has been established that it appears after the first calving in 27.8% cases, after the second to fifth calving in 66.7% cases, and after the sixth and seventh calving in 5.5% of the cows. The response of endocrine pancreas B-cells for insulin secretion to hyperglycaemia caused by applying an excess-glucose test is reduced in cows with left abomasal displacement, and there is constant hyperglycaemia in cows with right abomasal displacement. The excess-glucose test indicates a disrupted function of the endocrine pancreas in diseased animals. It has been determined through examinations of Aml genotypes in Holstein cow herds in connection with the appearance of abomasal displacement, that the occurrence of this disorder cannot be attributed to a genetic predisposition.
Conflict, displacement and health in the Middle East.

Science.gov (United States)

Mowafi, Hani

2011-01-01

Displacement is a hallmark of modern humanitarian emergencies. Displacement itself is a traumatic event that can result in illness or death. Survivors face challenges including lack of adequate shelter, decreased access to health services, food insecurity, loss of livelihoods, social marginalisation as well as economic and sexual exploitation. Displacement takes many forms in the Middle East and the Arab World. Historical conflicts have resulted in long-term displacement of Palestinians. Internal conflicts have driven millions of Somalis and Sudanese from their homes. Iraqis have been displaced throughout the region by invasion and civil strife. In addition, large numbers of migrants transit Middle Eastern countries or live there illegally and suffer similar conditions as forcibly displaced people. Displacement in the Middle East is an urban phenomenon. Many displaced people live hidden among host country populations in poor urban neighbourhoods - often without legal status. This represents a challenge for groups attempting to access displaced populations. Furthermore, health information systems in host countries often do not collect data on displaced people, making it difficult to gather data needed to target interventions towards these vulnerable populations. The following is a discussion of the health impacts of conflict and displacement in the Middle East. A review was conducted of published literature on migration and displacement in the region. Different cases are discussed with an emphasis on the recent, large-scale and urban displacement of Iraqis to illustrate aspects of displacement in this region.
Gender-based violence in conflict and displacement: qualitative findings from displaced women in Colombia.

Science.gov (United States)

Wirtz, Andrea L; Pham, Kiemanh; Glass, Nancy; Loochkartt, Saskia; Kidane, Teemar; Cuspoca, Decssy; Rubenstein, Leonard S; Singh, Sonal; Vu, Alexander

2014-01-01

Gender-based violence (GBV) is prevalent among, though not specific to, conflict affected populations and related to multifarious levels of vulnerability of conflict and displacement. Colombia has been marked with decades of conflict, with an estimated 5.2 million internally displaced persons (IDPs) and ongoing violence. We conducted qualitative research to understand the contexts of conflict, displacement and dynamics with GBV. This as part of a multi-phase, mixed method study, in collaboration with UNHCR, to develop a screening tool to confidentially identify cases of GBV for referral among IDP women who were survivors of GBV. Qualitative research was used to identify the range of GBV, perpetrators, contexts in conflict and displacement, barriers to reporting and service uptake, as well as to understand experiences of service providers. Thirty-five female IDPs, aged 18 years and older, who self-identified as survivors of GBV were enrolled for in-depth interviews in San Jose de Guaviare and Quibdo, Colombia in June 2012. Thirty-one service providers participated in six focus group discussions and four interviews across these sites. Survivors described a range of GBV across conflict and displacement settings. Armed actors in conflict settings perpetrated threats of violence and harm to family members, child recruitment, and, to a lesser degree, rape and forced abortion. Opportunistic violence, including abduction, rape, and few accounts of trafficking were more commonly reported to occur in the displacement setting, often perpetrated by unknown individuals. Intrafamilial violence, intimate partner violence, including physical and sexual violence and reproductive control were salient across settings and may be exacerbated by conflict and displacement. Barriers to reporting and services seeking were reported by survivors and providers alike. Findings highlight the need for early identification of GBV cases, with emphasis on confidential approaches and active
Thermal-recovery of modal instability in rod fiber amplifiers

DEFF Research Database (Denmark)

Jørgensen, Mette Marie; Laurila, Marko; Noordegraaf, Danny

2013-01-01

We investigate the temporal dynamics of Modal instabilities (MI) in ROD fiber amplifiers using a 100 μm core rod fiber in a single-pass amplifier configuration, and we achieve ~200W of extracted output power before the onset of MI. Above the MI threshold, we investigate the temporal dynamics of b...... and thermally annealed between each test series. We find that the MI threshold degrades as it is reached multiple times, but is recovered by thermal annealing. We also find that the test history of the rods affects the temporal dynamics....
Comparative Effects of Biomass Pre-Treatments for Direct and Indirect Transesterification to Enhance Microalgal Lipid Recovery

International Nuclear Information System (INIS)

Ghasemi Naghdi, Forough; Thomas-Hall, Skye R.; Durairatnam, Reuben; Pratt, Steven; Schenk, Peer M.

2014-01-01

Microalgal lipid recovery for biodiesel production is currently considered suboptimal, but pre-treatment of algal biomass, the use of solvent mixtures and the positioning of transesterification can lead to increased yields. Here, the effect of various reportedly successful pre-treatments and solvent mixtures were directly compared to each other and combined with direct and indirect transesterification methods using the oleaginous microalga Tetraselmis sp. M8. Microwave and thermal pre-treatments were applied and the total lipid and fatty acid methyl ester (FAME) recoveries were investigated. The application of pre-treatments increased FAME recovery through indirect transesterification when a Soxhlet system was used but they had no significant effect for direct transesterification. Gravimetric analyses of total lipids revealed that lipid recovery was highest when utilizing the chloroform-based Bligh and Dyer extraction method; however, FAME yield was the highest when applying a Soxhlet system utilizing a solvent mixture of hexane–ethanol (3:1). Total lipid recovery did not necessarily correlate with the recovery of FAMEs. The highest FAME recovery was achieved from thermal or microwave pre-treated biomass followed by indirect transesterification through Soxhlet extraction. FAME recovery could be more than doubled (increase of up to 171%) under these conditions. We conclude that a simple thermal pre-treatment (80°C for 10 min) in combination with solvent mixture extraction through indirect transesterification may present a cost-effective and scalable option for large-scale lipid extraction from microalgae.
Comparative effects of biomass pre-treatments for direct and indirect transesterification to enhance microalgal lipid recovery

Directory of Open Access Journals (Sweden)

Forough eGhasemi Naghdi

2014-12-01

Full Text Available Microalgal lipid recovery for biodiesel production is currently considered suboptimal, but pre-treatment of algal biomass, the use of solvent mixtures and the positioning of transesterification can lead to increased yields. Here, the effect of various reportedly successful pre-treatments and solvent mixtures were directly compared to each other and combined with direct and indirect transesterification methods using the oleaginous microalga Tetraselmis sp. M8. Microwave and thermal pre-treatments were applied and the total lipid and fatty acid methyl ester (FAME recoveries were investigated. The application of pre-treatments increased FAME recovery through indirect transesterification when a Soxhlet system was used but they had no significant effect for direct transesterification. Gravimetric analyses of total lipids revealed that lipid recovery was highest when utilizing the chloroform-based Bligh and Dyer extraction method; however FAME yield was the highest when applying a Soxhlet system utilizing a solvent mixture of hexane-ethanol (3:1. Total lipid recovery did not necessarily correlate with the recovery of FAMEs. The highest FAME recovery was achieved from thermal or microwave pre-treated biomass followed by indirect transesterification through Soxhlet extraction. FAME recovery could be more than doubled (increase of up to 171% under these conditions. We conclude that a simple thermal pre-treatment (80°C for 10 min in combination with solvent mixture extraction through indirect transesterification may present a cost-effective and scalable option for large-scale lipid extraction from microalgae.
Comparative Effects of Biomass Pre-Treatments for Direct and Indirect Transesterification to Enhance Microalgal Lipid Recovery

Energy Technology Data Exchange (ETDEWEB)

Ghasemi Naghdi, Forough; Thomas-Hall, Skye R.; Durairatnam, Reuben [Algae Biotechnology Laboratory, School of Agriculture and Food Sciences, The University of Queensland, Brisbane, QLD (Australia); Pratt, Steven [School of Chemical Engineering, The University of Queensland, Brisbane, QLD (Australia); Schenk, Peer M., E-mail: p.schenk@uq.edu.au [Algae Biotechnology Laboratory, School of Agriculture and Food Sciences, The University of Queensland, Brisbane, QLD (Australia)

2014-12-04

Microalgal lipid recovery for biodiesel production is currently considered suboptimal, but pre-treatment of algal biomass, the use of solvent mixtures and the positioning of transesterification can lead to increased yields. Here, the effect of various reportedly successful pre-treatments and solvent mixtures were directly compared to each other and combined with direct and indirect transesterification methods using the oleaginous microalga Tetraselmis sp. M8. Microwave and thermal pre-treatments were applied and the total lipid and fatty acid methyl ester (FAME) recoveries were investigated. The application of pre-treatments increased FAME recovery through indirect transesterification when a Soxhlet system was used but they had no significant effect for direct transesterification. Gravimetric analyses of total lipids revealed that lipid recovery was highest when utilizing the chloroform-based Bligh and Dyer extraction method; however, FAME yield was the highest when applying a Soxhlet system utilizing a solvent mixture of hexane–ethanol (3:1). Total lipid recovery did not necessarily correlate with the recovery of FAMEs. The highest FAME recovery was achieved from thermal or microwave pre-treated biomass followed by indirect transesterification through Soxhlet extraction. FAME recovery could be more than doubled (increase of up to 171%) under these conditions. We conclude that a simple thermal pre-treatment (80°C for 10 min) in combination with solvent mixture extraction through indirect transesterification may present a cost-effective and scalable option for large-scale lipid extraction from microalgae.
Characterization and Alteration of Wettability States of Alaskan Reserviors to Improve Oil Recovery Efficiency (including the within-scope expansion based on Cyclic Water Injection - a pulsed waterflood for Enhanced Oil Recovery)

Energy Technology Data Exchange (ETDEWEB)

Abhijit Dandekar; Shirish Patil; Santanu Khataniar

2008-12-31

Numerous early reports on experimental works relating to the role of wettability in various aspects of oil recovery have been published. Early examples of laboratory waterfloods show oil recovery increasing with increasing water-wetness. This result is consistent with the intuitive notion that strong wetting preference of the rock for water and associated strong capillary-imbibition forces gives the most efficient oil displacement. This report examines the effect of wettability on waterflooding and gasflooding processes respectively. Waterflood oil recoveries were examined for the dual cases of uniform and non-uniform wetting conditions. Based on the results of the literature review on effect of wettability and oil recovery, coreflooding experiments were designed to examine the effect of changing water chemistry (salinity) on residual oil saturation. Numerous corefloods were conducted on reservoir rock material from representative formations on the Alaska North Slope (ANS). The corefloods consisted of injecting water (reservoir water and ultra low-salinity ANS lake water) of different salinities in secondary as well as tertiary mode. Additionally, complete reservoir condition corefloods were also conducted using live oil. In all the tests, wettability indices, residual oil saturation, and oil recovery were measured. All results consistently lead to one conclusion; that is, a decrease in injection water salinity causes a reduction in residual oil saturation and a slight increase in water-wetness, both of which are comparable with literature observations. These observations have an intuitive appeal in that water easily imbibes into the core and displaces oil. Therefore, low-salinity waterfloods have the potential for improved oil recovery in the secondary recovery process, and ultra low-salinity ANS lake water is an attractive source of injection water or a source for diluting the high-salinity reservoir water. As part of the within-scope expansion of this project
Displacement sensing system and method

Science.gov (United States)

VunKannon, Jr., Robert S

2006-08-08

A displacement sensing system and method addresses demanding requirements for high precision sensing of displacement of a shaft, for use typically in a linear electro-dynamic machine, having low failure rates over multi-year unattended operation in hostile environments. Applications include outer space travel by spacecraft having high-temperature, sealed environments without opportunity for servicing over many years of operation. The displacement sensing system uses a three coil sensor configuration, including a reference and sense coils, to provide a pair of ratio-metric signals, which are inputted into a synchronous comparison circuit, which is synchronously processed for a resultant displacement determination. The pair of ratio-metric signals are similarly affected by environmental conditions so that the comparison circuit is able to subtract or nullify environmental conditions that would otherwise cause changes in accuracy to occur.
Magnetic resonance separation imaging using a divided inversion recovery technique (DIRT).

Science.gov (United States)

Goldfarb, James W

2010-04-01

The divided inversion recovery technique is an MRI separation method based on tissue T(1) relaxation differences. When tissue T(1) relaxation times are longer than the time between inversion pulses in a segmented inversion recovery pulse sequence, longitudinal magnetization does not pass through the null point. Prior to additional inversion pulses, longitudinal magnetization may have an opposite polarity. Spatial displacement of tissues in inversion recovery balanced steady-state free-precession imaging has been shown to be due to this magnetization phase change resulting from incomplete magnetization recovery. In this paper, it is shown how this phase change can be used to provide image separation. A pulse sequence parameter, the time between inversion pulses (T180), can be adjusted to provide water-fat or fluid separation. Example water-fat and fluid separation images of the head, heart, and abdomen are presented. The water-fat separation performance was investigated by comparing image intensities in short-axis divided inversion recovery technique images of the heart. Fat, blood, and fluid signal was suppressed to the background noise level. Additionally, the separation performance was not affected by main magnetic field inhomogeneities.

Effects of Fault Displacement on Emplacement Drifts

International Nuclear Information System (INIS)

Duan, F.

2000-01-01

The purpose of this analysis is to evaluate potential effects of fault displacement on emplacement drifts, including drip shields and waste packages emplaced in emplacement drifts. The output from this analysis not only provides data for the evaluation of long-term drift stability but also supports the Engineered Barrier System (EBS) process model report (PMR) and Disruptive Events Report currently under development. The primary scope of this analysis includes (1) examining fault displacement effects in terms of induced stresses and displacements in the rock mass surrounding an emplacement drift and (2 ) predicting fault displacement effects on the drip shield and waste package. The magnitude of the fault displacement analyzed in this analysis bounds the mean fault displacement corresponding to an annual frequency of exceedance of 10 -5 adopted for the preclosure period of the repository and also supports the postclosure performance assessment. This analysis is performed following the development plan prepared for analyzing effects of fault displacement on emplacement drifts (CRWMS M and O 2000). The analysis will begin with the identification and preparation of requirements, criteria, and inputs. A literature survey on accommodating fault displacements encountered in underground structures such as buried oil and gas pipelines will be conducted. For a given fault displacement, the least favorable scenario in term of the spatial relation of a fault to an emplacement drift is chosen, and the analysis is then performed analytically. Based on the analysis results, conclusions are made regarding the effects and consequences of fault displacement on emplacement drifts. Specifically, the analysis will discuss loads which can be induced by fault displacement on emplacement drifts, drip shield and/or waste packages during the time period of postclosure
High-displacement spiral piezoelectric actuators

Science.gov (United States)

Mohammadi, F.; Kholkin, A. L.; Jadidian, B.; Safari, A.

1999-10-01

A high-displacement piezoelectric actuator, employing spiral geometry of a curved piezoelectric strip is described. The monolithic actuators are fabricated using a layered manufacturing technique, fused deposition of ceramics, which is capable of prototyping electroceramic components with complex shapes. The spiral actuators (2-3 cm in diameter) consisted of 4-5 turns of a lead zirconate titanate ceramic strip with an effective length up to 28 cm. The width was varied from 0.9 to 1.75 mm with a height of 3 mm. When driven by the electric field applied across the width of the spiral wall, the tip of the actuator was found to displace in both radial and tangential directions. The tangential displacement of the tip was about 210 μm under the field of 5 kV/cm. Both the displacement and resonant frequency of the spirals could be tailored by changing the effective length and wall width. The blocking force of the actuator in tangential direction was about 1 N under the field of 5 kV/cm. These properties are advantageous for high-displacement low-force applications where bimorph or monomorph actuators are currently employed.
Thermal performance and heat transport in aquifer thermal energy storage

Science.gov (United States)

Sommer, W. T.; Doornenbal, P. J.; Drijver, B. C.; van Gaans, P. F. M.; Leusbrock, I.; Grotenhuis, J. T. C.; Rijnaarts, H. H. M.

2014-01-01

Aquifer thermal energy storage (ATES) is used for seasonal storage of large quantities of thermal energy. Due to the increasing demand for sustainable energy, the number of ATES systems has increased rapidly, which has raised questions on the effect of ATES systems on their surroundings as well as their thermal performance. Furthermore, the increasing density of systems generates concern regarding thermal interference between the wells of one system and between neighboring systems. An assessment is made of (1) the thermal storage performance, and (2) the heat transport around the wells of an existing ATES system in the Netherlands. Reconstruction of flow rates and injection and extraction temperatures from hourly logs of operational data from 2005 to 2012 show that the average thermal recovery is 82 % for cold storage and 68 % for heat storage. Subsurface heat transport is monitored using distributed temperature sensing. Although the measurements reveal unequal distribution of flow rate over different parts of the well screen and preferential flow due to aquifer heterogeneity, sufficient well spacing has avoided thermal interference. However, oversizing of well spacing may limit the number of systems that can be realized in an area and lower the potential of ATES.
Thermal and structural analysis of a cryogenic conduction cooling system for a HTS NMR magnet

Energy Technology Data Exchange (ETDEWEB)

In, Se Hwan; Hong, Yong Jun; Yeom, Han Kil; Ko, Hyo Bong; Park, Seong Je [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

2016-03-15

The superconducting NMR magnets have used cryogen such as liquid helium for their cooling. The conduction cooling method using cryocoolers, however, makes the cryogenic cooling system for NMR magnets more compact and user-friendly than the cryogen cooling method. This paper describes the thermal and structural analysis of a cryogenic conduction cooling system for a 400 MHz HTS NMR magnet, focusing on the magnet assembly. The highly thermo-conductive cooling plates between HTS double pancake coils are used to transfer the heat generated in coils, namely Joule heating at lap splice joints, to thermal link blocks and finally the cryocooler. The conduction cooling structure of the HTS magnet assembly preliminarily designed is verified by thermal and structural analysis. The orthotropic thermal properties of the HTS coil, thermal contact resistance and radiation heat load are considered in the thermal analysis. The thermal analysis confirms the uniform temperature distribution for the present thermal design of the NMR magnet within 0.2 K. The mechanical stress and the displacement by the electromagnetic force and the thermal contraction are checked to verify structural stability. The structural analysis indicates that the mechanical stress on each component of the magnet is less than its material yield strength and the displacement is acceptable in comparison with the magnet dimension.
Thermal treatment of sewage sludge from waste water. Tratamiento termico de lodos procedentes de aguas residuales

Energy Technology Data Exchange (ETDEWEB)

Andreottola, G. (Universidad de Trento (Italy)); Canziani, R.; Ragazzi, M. (Politicnico de Milan (Italy))

1994-01-01

Thermal Treatment of sewage sludge can be beneficial as a pre-treatment step of many treatment/disposal options, but above all, it allows the recovery of the energetic content sludge. Energy recovery from sewage sludge can be performed in many ways; direct incineration thermal drying followed by incineration and co-combustion with municipal solid wastes or other non conventional fuels. Another option is the recovery of waste energy (e.g. from an endo thermal engine using biogas as fuel) to dry sludge wich, in turn can be used as a fuel. The paper will evaluate several options of thermal treatment of sewage sludge, with particular emphasis on the energetic yield from different processes. (Author)
Experimental results of thermally controlled superconducting switches for high frequency operation

International Nuclear Information System (INIS)

Mulder, G.B.J.; IerAvest, D.; Tenkate, H.H.J.; Krooshoop, H.J.G.; Van de Klundert, L.

1988-01-01

The aim of this study is to develop thermally controlled switches which are to be used in superconducting rectifiers operating at a few hertz and 1 kA. Usually, the operating frequency of thermally controlled rectifiers is limited to about 0.1 Hz due to the thermal recovery times of the switches. The thermal switches have to satisfy two conditions which are specific for the application in a superconducting rectifier: a) they have to operate in the repetitive mode so beside short activation times, fast recovery times of the switches are equally important, b) the power required to effect and maintain the normal state of the switches should be low since it will determine the rectifier efficiency. To what extent these obviously conflicting demands can be satisfied depends on the material and geometry of the switch. This paper presents a theoretical model of the thermal behaviour of a switch. The calculations are compared with experimental results of several switches having recovery times between 40 and 200 ms. Also, the feasibility of such switches for application in superconducting rectifiers operating at a few hertz with an acceptable efficiency is demonstrated
Imaging Correlations in Heterodyne Spectra for Quantum Displacement Sensing

Science.gov (United States)

Pontin, A.; Lang, J. E.; Chowdhury, A.; Vezio, P.; Marino, F.; Morana, B.; Serra, E.; Marin, F.; Monteiro, T. S.

2018-01-01

The extraordinary sensitivity of the output field of an optical cavity to small quantum-scale displacements has led to breakthroughs such as the first detection of gravitational waves and of the motions of quantum ground-state cooled mechanical oscillators. While heterodyne detection of the output optical field of an optomechanical system exhibits asymmetries which provide a key signature that the mechanical oscillator has attained the quantum regime, important quantum correlations are lost. In turn, homodyning can detect quantum squeezing in an optical quadrature but loses the important sideband asymmetries. Here we introduce and experimentally demonstrate a new technique, subjecting the autocorrelators of the output current to filter functions, which restores the lost heterodyne correlations (whether classical or quantum), drastically augmenting the useful information accessible. The filtering even adjusts for moderate errors in the locking phase of the local oscillator. Hence we demonstrate the single-shot measurement of hundreds of different field quadratures allowing the rapid imaging of detailed features from a simple heterodyne trace. We also obtain a spectrum of hybrid homodyne-heterodyne character, with motional sidebands of combined amplitudes comparable to homodyne. Although investigated here in a thermal regime, the method's robustness and generality represents a promising new approach to sensing of quantum-scale displacements.
Qinshan phase II extension nuclear power project thermal stratification and fatigue stress analysis for pressurizer surge line

International Nuclear Information System (INIS)

Yu Xiaofei; Zhang Yixiong; Ai Honglei

2010-01-01

Thermal stratification of pressurizer surge line induced by the inside fluid brings on global bending moments, local thermal stresses, unexpected displacements and support loadings of the pipe system. In order to avoid a costly three-dimensional computation, a combined 1D/2D technique has been developed and implemented to analyze the thermal stratification and fatigue stress of pressurize surge line of QINSHAN Phase II Extension Nuclear Power Project in this paper, using the computer codes SYSTUS and ROCOCO. According to the mechanical analysis results of stratification, the maximum stress and cumulative usage factor, the loadings at connections of surge line to main pipe and RCP and the displacements of surge line at supports are obtained. (authors)
Recovery of deuterium from H-D gas mixture by thermal diffusion in a multi-concentric-tube column device of fixed total sum of column heights with transverse sampling streams

International Nuclear Information System (INIS)

Yeh, H.-M.

2010-01-01

The effect of the increment in the number of concentric-tube thermal diffusion columns on the recovery of deuterium from H 2 -HD-D 2 system with fixed total sum of column heights, has been investigated. The equations for predicting the degrees of separation in single-column, double-column and triple-column devices have been derived. Considerable improvement in recovery can be achieved if a multi-column device with larger number of column is employed, instead of a single-column device with column height equal to the same total sum of column heights, especially for the case of higher flow-rate operation and larger total sum of column heights.
Atomistic simulations of displacement cascades in Y2O3 single crystal

International Nuclear Information System (INIS)

Dholakia, Manan; Chandra, Sharat; Valsakumar, M.C.; Mathi Jaya, S.

2014-01-01

Graphical abstract: (a) The averaged distortion index and the Y–O bond length of the Y 2 O 3 octahedra as a function of the simulation time for 5 keV PKA. (b) Shows the nearest neighbourhood of one of the Y ions as a function of simulation time, showing the destruction and the recovery of the YO 6 octahedron during the cascade corresponding to 5 keV Y PKA. - Highlights: • Qualitative difference in displacement cascades exists for Y and O PKA. • Nearest neighbour correlation between Y and O ions exists even at cascade peak. • Cascade core in Y 2 O 3 does not undergo melting. • Topological connectivity of YO 6 polyhedra plays important role in stability of Y 2 O 3 . - Abstract: We study the characteristics of displacement cascades in single crystal Y 2 O 3 using classical molecular dynamics. There are two possible ways to generate the cascades in yttria, using either the Y or the O atoms as the primary knock-on (PKA) atom. It is shown that there is a qualitative difference in the characteristics of the cascades obtained in these two cases. Even though the crystal is seen to be in a highly disordered state in the cascade volume, as seen from the plots of radial distribution function, the correlation between the Y and O atoms is not completely lost. This facilitates a quick recovery of the system during the annealing phase. Topological connectivity of the YO 6 polyhedral units plays an important role in imparting stability to the Y 2 O 3 crystal. These characteristics of the cascades can help explain the stability of the yttria nanoparticles when they are dispersed in oxide dispersion strengthened steels
On broadened definitions of instability for stars in thermal imbalance

International Nuclear Information System (INIS)

Simon, N.R.

1977-01-01

The classical theory of stability of dynamical systems is employed to demonstrate that traditional definitions of pulsational instability cannot be directly applied to stars in thermal imbalance. In particular, it is shown that, for the case of thermal imbalance, pulsational displacements and pulsational velocities have separate and distinct e-folding times. This being true, a broadened set of definitions becomes necessary, and such a set is formulated again with reference to the classical theory. In accordance with the new definitions, it is argued that the development of observable pulsations requires as a necessary condition infinitesimal instability of both absolute displacement and velocity. If either one is unstable without the other, this constitutes a class of (probably) non-pulsational instability, not previously treated in the astrophysical literature. Finally, it is shown that the stability of stars in thermal imbalance may be evaluated according to the present definitions by employing either of two existing theories - the energy approach due to Demaret (1974; 1975; 1976) or the small perturbation technique of Cox et al. (1973). (Auth.)
Peroneal tendon displacement accompanying intra-articular calcaneal fractures.

Science.gov (United States)

Toussaint, Rull James; Lin, Darius; Ehrlichman, Lauren K; Ellington, J Kent; Strasser, Nicholas; Kwon, John Y

2014-02-19

Peroneal tendon displacement (subluxation or dislocation) accompanying an intra-articular calcaneal fracture is often undetected and under-treated. The goals of this study were to determine (1) the prevalence of peroneal tendon displacement accompanying intra-articular calcaneal fractures, (2) the association of tendon displacement with fracture classifications, (3) the association of tendon displacement with heel width, and (4) the rate of missed diagnosis of the tendon displacement on radiographs and computed tomography (CT) scans and the resulting treatment rate. A retrospective radiographic review of all calcaneal fractures presenting at three institutions from June 30, 2006, to June 30, 2011, was performed. CT imaging of 421 intra-articular calcaneal fractures involving the posterior facet was available for review. The prevalence of peroneal tendon displacement was noted and its associations with fracture classification and heel width were evaluated. Peroneal tendon displacement was identified in 118 (28.0%) of the 421 calcaneal fracture cases. The presence of tendon displacement was significantly associated with joint-depression fractures compared with tongue-type fractures (p displacement had been identified in the radiology reports. Although sixty-five (55.1%) of the fractures with tendon displacement had been treated with internal fixation, the tendon displacement was treated surgically in only seven (10.8%) of these cases. Analysis of CT images showed a 28% prevalence of peroneal tendon displacement accompanying intra-articular calcaneal fractures. Surgeons and radiologists are encouraged to consider this association.
Surface flaw in a thermally shocked hollow cylinder

International Nuclear Information System (INIS)

Kobayashi, A.S.; Emery, A.F.; Polvanich, N.; Love, W.J.

1975-01-01

The objective of this paper is to illustrate a procedure for estimating the stress intensity factors of a semi-elliptical crack located in the inner or outer surface of a thermally shocked hollow cylinder. The first step in this procedure is to estimate the transient thermal elastic stresses induced by sudden cooling of an uncracked cylinder by numerically evaluating standard heat transfer and thermal stress formulae. The stresses at the location of the crack surface in the uncracked cylinder are eliminated by the method of superposition in order to obtain a stress free crack surface. The stress intensity factors are then determined by a judicious use of two sets of solutions, one set involving stress intensity factors for a semi-elliptical crack in a flat plate and subjected to a polynomial distribution of pressure loading, and another set involving single-edge notched plates with prescribed edge-displacements and single-edge internally or externally notched cylinders with thermal shock loading. The former solutions are determined by the alternating technique in three-dimensional fracture mechanics with a fourth order polynomial pressure distribution on the crack surface where both the front and back surface effects are accounted for. The latter solutions involve two-dimensional finite element solutions of single-edge notched plates with prescribed edge-displacements and single-edge notched cylinders with thermal shock loading. By comparing these two two-dimensional solutions, an estimate of the effect of the cylindrical curvature on an edge-cracked plate is obtained. The combination of these two sets of solutions thus yields an estimate of the stress intensity factor in an internal and external semi-elliptical crack in a thermally shocked cylinder
Design and fabrication of a MEMS chevron-type thermal actuator

Energy Technology Data Exchange (ETDEWEB)

Baracu, Angela, E-mail: angela.baracu@imt.ro [Laboratory of Modeling, Simulation and CAD, National Institute for R and D in Microtechnologies - IMT Bucharest, 126A, Erou Iancu Nicolae Street, 077190, Bucharest, Romania and University Politehnica of Bucharest (Romania); Voicu, Rodica; Müller, Raluca; Avram, Andrei [Laboratory of Modeling, Simulation and CAD, National Institute for R and D in Microtechnologies - IMT Bucharest, 126A, Erou Iancu Nicolae Street, 077190, Bucharest (Romania); Pustan, Marius, E-mail: marius.pustan@omt.utcluj.ro; Chiorean, Radu, E-mail: marius.pustan@omt.utcluj.ro; Birleanu, Corina, E-mail: marius.pustan@omt.utcluj.ro; Dudescu, Cristian, E-mail: marius.pustan@omt.utcluj.ro [Laboratory of Micro and Nano Systems, Technical University of Cluj-Napoca, Bd. Muncii, no. 103-105, 400641 Cluj-Napoca (Romania)

2015-02-17

This paper presents the design and fabrication of a MEMS chevron-type thermal actuator. The device was designed for fabrication in the standard MEMS technology, where the topography of the upper layers depends on the patterns of structural and sacrificial layers underneath. The proposed actuator presents some advantages over usual thermal vertical chevron actuators by means of low operating voltages, high output force and linear movement without deformation of the shaft. The device simulations were done using COVENTOR software. The movement obtained by simulation was 12 μm, for a voltage of 0.2 V and the current intensity of 257 mA. The design optimizes the in-plane displacement by fixed anchors and beam inclination angle. Heating is provided by Joule dissipation. The material used for manufacture of chevron-based actuator was aluminum due to its thermal and mechanical properties. The release of the movable part was performed using isotropic dry etching by Reactive Ion Etching (RIE). A first inspection was achieved using Scanning Electron Microscope (SEM). In order to obtain the in-plane displacement we carried out electrical measurements. The thermal actuator can be used for a variety of optical and microassembling applications. This kind of thermal actuator could be integrated easily with other micro devices since its fabrication is compatible with the general semiconductor processes.
A study on thermal ratcheting structure test of 316L test cylinder

International Nuclear Information System (INIS)

Lee, H. Y.; Kim, J. B.; Koo, G. H.

2001-01-01

In this study, the progressive inelastic deformation, so called, thermal ratchet phenomenon which can occur in high temperature liquid metal reactor was simulated with thermal ratchet structural test facility and 316L stainless steel test cylinder. The inelastic deformation of the reactor baffle cylinder can occur due to the moving temperature distribution along the axial direction as the hot free surface moves up and down under the cyclic heat-up and cool-down of reactor operations. The ratchet deformations were measured with the laser displacement sensor and LVDTs after cooling the structural specimen which experiences thermal load up to 550 .deg. C and the temperature differences of about 500 .deg. C. During structural thermal ratchet test, the temperature distribution of the test cylinder along the axial direction was measured from 28 channels of thermocouples and the temperatures were used for the ratchet analysis. The thermal ratchet deformation analysis was performed with the NONSTA code whose constitutive model is nonlinear combined kinematic and isotropic hardening model and the test results were compared with those of the analysis. Thermal ratchet test was carried out with respect to 9 cycles of thermal loading and the maximum residual displacements were measured to be 1.8mm. It was shown that thermal ratchet load can cause a progressive deformation to the reactor structure. The analysis results with the combined hardening model were in reasonable agreement with those of the tests
Project-induced displacement, secondary stressors, and health.

Science.gov (United States)

Cao, Yue; Hwang, Sean-Shong; Xi, Juan

2012-04-01

It has been estimated that about 15 million people are displaced by development projects around the world each year. Despite the magnitude of people affected, research on the health and other impacts of project-induced displacement is rare. This study extends existing knowledge by exploring the short-term health impact of a large scale population displacement resulting from China's Three Gorges Dam Project. The study is theoretically guided by the stress process model, but we supplement it with Cernea's impoverishment risks and reconstruction (IRR) model widely used in displacement literature. Our panel analysis indicates that the displacement is associated positively with relocatees' depression level, and negatively with their self-rated health measured against a control group. In addition, a path analysis suggests that displacement also affects depression and self-rated health indirectly by changing social integration, socioeconomic status, and community resources. The importance of social integration as a protective mechanism, a factor that has been overlooked in past studies of population displacement, is highlighted in this study. Published by Elsevier Ltd.
Thermal response of integral abutment bridges with mechanically stabilized earth walls.

Science.gov (United States)

2013-03-01

The advantages of integral abutment bridges (IABs) include reduced maintenance costs and increased useful life spans. : However, improved procedures are necessary to account for the impacts of cyclic thermal displacements on IAB components, : includi...
Economic analysis of using excess renewable electricity to displace heating fuels

DEFF Research Database (Denmark)

Pensini, Alessandro; Rasmussen, Claus Nygaard; Kempton, Willett

2014-01-01

. Because excess electricity appears to be cost-optimum, this raises the question as to whether the excess electricity, which in the case of wind power is predominately produced in colder weather, might displace other fuels for purposes such as heat. This study models using excess electricity for heating......, based on an analysis of electricity and heat use in a TSO in the North-Eastern part of the United States (PJM Interconnection). The heating system was modeled as heat pump based district heating (HPDH) with thermal energy storage (TES). Thus, excess electricity is transformed into heat, which is easy....... An algorithm that calculates the total cost of a unit of heat was used to determine the economically optimal size of the system’s main components and the influence that natural gas (NG) and electricity prices have on this optimum. It was found that a system based on heat pumps (HP) and centralized thermal...
Influence of pH on dynamics of microbial enhanced oil recovery processes using biosurfactant producing Pseudomonas putida: Mathematical modelling and numerical simulation.

Science.gov (United States)

Sivasankar, P; Suresh Kumar, G

2017-01-01

In present work, the influence of reservoir pH conditions on dynamics of microbial enhanced oil recovery (MEOR) processes using Pseudomonas putida was analysed numerically from the developed mathematical model for MEOR processes. Further, a new strategy to improve the MEOR performance has also been proposed. It is concluded from present study that by reversing the reservoir pH from highly acidic to low alkaline condition (pH 5-8), flow and mobility of displaced oil, displacement efficiency, and original oil in place (OOIP) recovered gets significantly enhanced, resulting from improved interfacial tension (IFT) reduction by biosurfactants. At pH 8, maximum of 26.1% of OOIP was recovered with higher displacement efficiency. The present study introduces a new strategy to increase the recovery efficiency of MEOR technique by characterizing the biosurfactants for IFT min /IFT max values for different pH conditions and subsequently, reversing the reservoir pH conditions at which the IFT min /IFT max value is minimum. Copyright © 2016 Elsevier Ltd. All rights reserved.
Emittance growth rates for displaced beams

International Nuclear Information System (INIS)

Anderson, O.A.

1993-05-01

Emittance growth rates have been previously analyzed for nonuniform beams in linear channels and for initially uniform mismatched beams in nonlinear channels. These studies were for centered beams. Additional emittance growth can arise in cases where the beam is initially displaced. The purpose of this study is to obtain growth rates for displaced beams. This work differs from studies involving random displacement of electrodes. Our analysis assumes instead that the focusing system is perfectly aligned but that the beam is initially displaced with respect to the equilibrium axis. If the focusing force is slightly nonlinear, we find a gradual transfer of the potential energy of beam displacement into kinetic energy associated with emittance growth. We present explicit results for the emittance growth distance as a function of the nonlinearity of the channel. These results will have practical importance for designers of accelerators and transport systems when setting realistic tolerances for initial beam alignment. These tolerances will depend on the nonlinearity and the length of the system

Impacts of convection on high-temperature aquifer thermal energy storage

Science.gov (United States)

Beyer, Christof; Hintze, Meike; Bauer, Sebastian

2016-04-01

injection temperatures exceed 35°C. Convection results in an accumulation of heat below the upper confining layer. The consequential increase of the heat plume contact area with this formation results in increased conductive heat transfer. Also, thermal gradients between the heat plume and the ambient groundwater increase with injection temperature, which increases heat conduction within the aquifer. Both effects reduce the thermal recovery of the ATES system. At the end of the 10th injection / withdrawal cycle the efficiency of thermal recovery thus reaches about 76 % for the 20°C scenario, 74% for 35°C, 71 % for 60°C and 66 % for the 90 °C scenario. Sensitivity analysis indicates that permeability in horizontal and vertical directions are controlling factors for the extent of convective heat displacement. Also, heat plume dimensions are influenced by permeability, and to a lesser extent by heat capacity and porosity of the aquifer. The planning of high-temperature ATES at a specific site hence requires a careful investigation of hydraulic and heat transport properties. Acknowledgments: This work is part of the ANGUS+ project (www.angusplus.de) and funded by the German Federal Ministry of Education and Research (BMBF) as part of the energy storage initiative "Energiespeicher".
Is Fibular Fracture Displacement Consistent with Tibiotalar Displacement?

NARCIS (Netherlands)

van den Bekerom, Michel P. J.; van Dijk, C. Niek

2010-01-01

We believed open reduction with internal fixation is required for supination-external rotation ankle fractures located at the level of the distal tibiofibular syndesmosis (Lauge-Hanssen SER II and Weber B) with 2 mm or more fibular fracture displacement. The rationale for surgery for these ankle
Phenomenon of displacement in Arabic language

Directory of Open Access Journals (Sweden)

2015-09-01

Full Text Available Displacement is one of the characteristics of language and common phenomena in the Arabic language. Not only is this phenomenon limited to Arabic poetry and prose, but it is also broadened, so we can see examples of this in the Qur'an. Because of this phenomenon extensively in Arabic literature and also because of its essence that leads to the transmission of the elements for the first visibility to the other visibility in the sentence and sometimes had to change the grammatical role of the words, its identify helps us in a better understanding of text and the correct translation of it and protects the reader from mistakes. This paper in the descriptive analytical approach tries studying of the phenomenon of the displacement in the Arabic language and bringing its instances in Arabic poetry and prose as well as verses contained in the Holy Quran, to show that through the types and characteristics in the Arabic language and to response to several questions, including: how important is the displacement and what is its types in rhetoric, and the reasons of the displacement, and etc... Of the most important results of this study may refer to the undeniable role of the displacement as a rhetorical method to better understanding of the texts including: one of the most important reasons of the displacement in the use of language is to improve speech verbally and morally, and violation of the standard language and create a poetic atmosphere, and the recognition of the occurrence of the phenomenon of displacement in the Arabic language that uphold different interpretations remote and estimates when faced with the displacement in the text and help us to understand it and etc...
Cold storage condensation heat recovery system with a novel composite phase change material

International Nuclear Information System (INIS)

Xia, Mingzhu; Yuan, Yanping; Zhao, Xudong; Cao, Xiaoling; Tang, Zhonghua

2016-01-01

Highlights: • Cold storage condensation heat recovery system using PCM was proposed. • CW with a phase change temperature of nearly 80 °C was selected as the potential PCM. • The optimal mass ratio between the CW and EG was 10:1. • The thermal and physical performances of the CW/EG were investigated. • The thermal reliability was demonstrated by 1000 cycles. - Abstract: Using condensation heat from cold storage refrigeration systems to provide heat for domestic hot water preparation and industrial hot water supply promotes energy conservation. However, few studies have investigated cold storage condensation heat recovery using phase change materials (PCMs). In this study, a cold storage condensation heat recovery system that uses PCMs has been designed and analysed. According to the principle of energy cascade recycling, different operation modes could be effectively switched to recycle condensation heat. Furthermore, a novel and suitable phase change composite material is developed for cold storage condensation heat recovery, which has a relatively large latent heat, high thermal conductivity, and an appropriate phase change temperature (i.e. 80 °C). With carnauba wax (CW) as the PCM and expanded graphite (EG) as the additive, a composite was developed with an optimal mass ratio of CW:EG = 10:1. The thermal and physical properties and the interior structure of the composite were then investigated using a scanning electron microscope (SEM), thermal constants analyser (Hot Disk), differential scanning calorimeter (DSC), and Fourier transform infrared spectrometer (FT-IR). Furthermore, experiments on the melting and solidification processes and accelerated thermal cycling were also conducted. It was found that at the optimal mass ratio of 10:1, the temperatures of the CW/EG composite in the melting and solidification processes were 81.98 °C and 80.43 °C, respectively, while the corresponding latent heats were 150.9 J/g and 142.6 J/g, respectively
Experimental investigation of molten salt droplet quenching and solidification processes of heat recovery in thermochemical hydrogen production

International Nuclear Information System (INIS)

Ghandehariun, S.; Wang, Z.; Naterer, G.F.; Rosen, M.A.

2015-01-01

Highlights: • Thermal efficiency of a thermochemical cycle of hydrogen production is improved. • Direct contact heat recovery from molten salt is analyzed. • Falling droplets quenched into water are investigated experimentally. - Abstract: This paper investigates the heat transfer and X-ray diffraction patterns of solidified molten salt droplets in heat recovery processes of a thermochemical Cu–Cl cycle of hydrogen production. It is essential to recover the heat of the molten salt to enhance the overall thermal efficiency of the copper–chlorine cycle. A major portion of heat recovery within the cycle can be achieved by cooling and solidifying the molten salt exiting an oxygen reactor. Heat recovery from the molten salt is achieved by dispersing the molten stream into droplets. In this paper, an analytical study and experimental investigation of the thermal phenomena of a falling droplet quenched into water is presented, involving the droplet surface temperature during descent and resulting composition change in the quench process. The results show that it is feasible to quench the molten salt droplets for an efficient heat recovery process without introducing any material imbalance for the overall cycle integration.
Earthquake related displacement fields near underground facilities

International Nuclear Information System (INIS)

Pratt, H.R.; Zandt, G.; Bouchon, M.

1979-04-01

Relative displacements of rock masses are evaluated in terms of geological evidence, seismological evidence, data from simulation experiments, and analytical predictive models. Numerical models have been developed to determine displacement fields as a function of depth, distance, and azimuth from an earthquake source. Computer calculations for several types of faults indicate that displacements decrease rapidly with distance from the fault, but that displacements can either increase or decrease as a function of depth depending on the type and geometry of the fault. For long shallow vertical strike-slip faults the displacement decreases markedly with depth. For square strike slip faults and for dip slip faults displacement does not decrease as markedly with depth. Geologic structure, material properties, and depth affect the seismic source spectrum. Amplification of the high frequencies of shear waves is larger by a factor of about 2 for layered geologic models than for an elastic half space
A Thermal Energy Recovery System and its Applications in Building (A Short Comunication

Directory of Open Access Journals (Sweden)

Afsane Chavoshani

2016-01-01

Full Text Available In this paper a heat recovery system from oil heater as a water heater is proposed and analyzed. The potential of heat recovery is studied technically and economically. A model was built and experiments on it are discussed. Recovery of waste heat from the oil heater stack and its application in building is proven to be economically beneficial. The most part of this apparatus was a double-walled tanks and oil heater stack act as firebox for water heater. This tank with 200 liters volume was made of galvanized iron sheets and painted with black color for adsorption of solar radiation. The tank of water heater was filled with 12-15○C water. Sampling was performed at 8 in the morning to 8 at night during one week. The analysis results show that the heat recovery system is recognized as a well option for the examined residential building from both economic and environmental points of view. With the operation considering optimal economic benefits, cost is reduced by about 50%. With maximizing the environmental advantages, CO2 emissions are decreased.
A comparison of pine and spruce in recovery from winter stress; changes in recovery kinetics, and the abundance and phosphorylation status of photosynthetic proteins during winter.

Science.gov (United States)

Merry, Ryan; Jerrard, Jacob; Frebault, Julia; Verhoeven, Amy

2017-09-01

During winter evergreens maintain a sustained form of thermal energy dissipation that results in reduced photochemical efficiency measured using the chlorophyll fluorescence parameter Fv/Fm. Eastern white pine (Pinus strobus L.) and white spruce [Picea glauca (Moench) Voss] have been shown to differ in their rate of recovery of Fv/Fm from winter stress. The goal of this study was to monitor changes in photosynthetic protein abundance and phosphorylation status during winter recovery that accompany these functional changes. An additional goal was to determine whether light-dependent changes in light harvesting complex II (LHCII) phosphorylation occur during winter conditions. We used a combination of field measurements and recovery experiments to monitor chlorophyll fluorescence and photosynthetic protein content and phosphorylation status. We found that pine recovered three times more slowly than spruce, and that the kinetics of recovery in spruce included a rapid and slow component, while in pine there was only a rapid component to recovery. Both species retained relatively high amounts of the light harvesting protein Lhcb5 (CP26) and the PsbS protein during winter, suggesting a role for these proteins in sustained thermal dissipation. Both species maintained high phosphorylation of LHCII and the D1 protein in darkness during winter. Pine and spruce differed in the kinetics of the dephosphorylation of LHCII and D1 upon warming, suggesting the rate of dephosphorylation of LHCII and D1 may be important in the rapid component of recovery from winter stress. Finally, we demonstrated that light-dependent changes in LHII phosphorylation do not continue to occur on subzero winter days and that needles are maintained in a phosphorylation pattern consistent with the high light conditions to which those needles are exposed. Our results suggest a role for retained phosphorylation of both LHCII and D1 in maintenance of the photosynthetic machinery in a winter conformation
Experimental study on mass transfer of contaminants through an enthalpy recovery unit with polymer membrane foils

DEFF Research Database (Denmark)

Nie, Jinzhe; Fang, Lei

2014-01-01

Laboratory experimental studies were conducted to investigate the mass transfer of contaminants through a total heat recovery unit with polymer membranes foils. The studies were conducted in twin climate chambers which simulated outdoor and indoor thermal climates. One manufacturd total heat...... chemical gases were used to simulate air contaminants. The concentrations of dosed contaminants in the supply and exhaust air upstream and downstream of the total heat recovery unit were measured with Multi-Gas Monitor Innova 1316 in real time. Experiment results showed that 5% to 9% of dosed contaminants...... could transfer from exhaust air to supply air through the enthalpy recovery unit. The mass transfer efficiency of contaminants was independent of the hygro-thermal differences between indoor and outdoor climate conditions. The mass transfer ratio of the chemical contaminants in the total heat recovery...
SOCIAL CAPITAL IN INVOLUNTARY DISPLACEMENT AND RESETTLEMENT

Directory of Open Access Journals (Sweden)

Melissa Quetulio-Navarra

2013-07-01

Full Text Available Social capital is often seen as a substitute for lack of other types of capital amongpoor people. Because of the recognized applicability of the social capital conceptand its correlation with the different dimensions of poverty, it has been used inevaluating the adaptation and integration of involuntarily displaced individualsinto their new environment. This paper presents insights based on a review of thefindings of studies that looked into the role of social capital in conflict- anddevelopment-induced displacement contexts. Althoughboth types of displace-ments are involuntary or forced in nature, they differ in terms of the role of socialcapital regarding its main sources, the formation pattern and its determinants.Social capital studies in forced resettlement appear to be relatively small innumber and are heavily concentrated on first worldcountries and conflict- anddevelopment-induced displacements. The conduct of similar studies in developingcountries and in a disaster-induced resettlement context, the third type ofinvoluntary displacement, should generate new and relevant findings regardingthe role of social capital in resettlement communities.
War, forced displacement and growth in Laotian adults.

Science.gov (United States)

Clarkin, Patrick F

2012-01-01

Evidence from several populations suggests that war negatively impacts civilian nutrition, physical growth and overall health. This effect is often enduring or permanent, particularly if experienced early in life. To assess whether the number of lifetime displacement experiences and being displaced in infancy were associated with adult height, sitting height, leg length and the sitting height ratio. Retrospective questionnaires on displacement and resettlement experiences and anthropometric data were collected from a sample of Laotian adult refugees (ethnic Hmong and Lao; n = 365). All were born in Laos or Thailand and had resettled in French Guiana or the US. Many had been displaced several times by military conflict in Laos. In bivariate analyses, being displaced in infancy and the number of lifetime displacement experiences one had were negatively associated with final adult height and leg length in both sexes. The association was stronger in females, particularly Hmong females. There was no significant association between total displacement experiences and the sitting height ratio. In multiple regression analyses, linear growth in males was negatively associated with being displaced in infancy; in females, the number of lifetime displacement experiences was a significant predictor. Forced displacement from war appears to have a lasting effect on final adult height, sitting height and leg length, although not necessarily on the sitting height ratio in this sample.
Performance of ductless personalized ventilation in conjunction with displacement ventilation

DEFF Research Database (Denmark)

Dalewski, Mariusz; Melikov, Arsen Krikor; Vesely, Michal

2014-01-01

perception of the environment. The subjects could control the position of the DPV supply diffuser and the personalized air flow (air velocity). The use of DPV improved perceived air quality and thermal comfort compared to displacement ventilation alone. At 26 °C and 29 °C the percentage dissatisfied with air......, increased eye dryness sensation was reported by 30% of subjects. The personalized air flow selected by nearly 80% of the subjects at 26 °C was between 10 and 20 l/s corresponding to the target air velocity of 1.2–1.7 m/s. At 29 °C almost 90% of subjects chose a personalized air flow between 15 and 20 l/s (1...
Recovery of mouth-opening after closed treatment of a fracture of the mandibular condyle: a longitudinal study.

Science.gov (United States)

Niezen, E T; Stuive, I; Post, W J; Bos, R R M; Dijkstra, P U

2015-02-01

The aim of this retrospective study was to assess recovery of mouth opening after closed treatment of fractures of the mandibular condyle, and analyse which characteristics might influence recovery. We measured mouth opening in 142 patients (mean (SD) age 30 (14) years, 96 of whom were male) during follow-up at 3, 6, 13, 26, and 52 weeks after the injury. Fractures were assessed on radiographs. Data were analysed using a multilevel analysis. Half the fractures were of the low condylar neck (n=71). Thirty-seven patients had bilateral condylar fractures, 29 had dislocated fractures, and in 80 the fracture was displaced. One or more additional mandibular fractures were present in 68. During follow-up mean (SD) mouth opening increased to: 33.6 (9.6) at 3 weeks, 40.1 (10.0) at 6 weeks, 45.1 (9.6) at 13 weeks, 49.8 (9.5) at 26 weeks, and 52.6 (7.5) at 52 weeks. Older age, female sex, displaced fracture, bilateral fractures, additional mandibular fractures, and the interaction between follow-up time and additional mandibular fractures, were predictors of a less favourable recovery of mouth opening. Clinicians can use the results of this study to predict recovery of mouth opening after closed treatment of fractures of the mandibular condyle at first consultation. Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Shear Resistance Properties of Modified Nano-SiO2/AA/AM Copolymer Oil Displacement Agent

Directory of Open Access Journals (Sweden)

Nanjun Lai

2016-12-01

Full Text Available To address the problem regarding poor shear resistance of commonly employed polymers for oil displacement, modified nano-SiO2/AA/AM copolymer (HPMNS oil displacement agents were synthesized using acrylic acid (AA, acrylamide (AM, and modified nano-SiO2 of different modification degrees as raw materials. HPMNS was characterized by means of infrared spectroscopy (IR, nuclear magnetic resonance (1H-NMR, 13C-NMR, dynamic/static light scattering, and scanning electron microscope. A comparative study of the shear resistance properties for partially hydrolyzed polyacrylamide (HPAM and HPMNS was conducted. Compared to HPAM, the introduced hyperbranched structure endowed HPMNS with good shear resistance, which was quantified from the viscosity retention ratio of the polymer solutions. From the perspective of rheological property, HPMNS also showed great shear stability after shearing by a Mixing Speed Governor and porous media shear model. Furthermore, with a higher degree of modification, HPMNS-2 had better shear stability in terms of viscosity and rheological property than HPMNS-1. The phenomena were due to its lower hydrodynamic radius, weight-average molecular weight, and better flexibility of its molecular chains. In addition, upon the indoor displacement test, the resistance factor and residual resistance factor values of HPMNS-2 were higher than those of HPAM. This behavior is beneficial for increasing oil recovery.
A New Screening Methodology for Improved Oil Recovery Processes Using Soft-Computing Techniques

Science.gov (United States)

Parada, Claudia; Ertekin, Turgay

2010-05-01

The first stage of production of any oil reservoir involves oil displacement by natural drive mechanisms such as solution gas drive, gas cap drive and gravity drainage. Typically, improved oil recovery (IOR) methods are applied to oil reservoirs that have been depleted naturally. In more recent years, IOR techniques are applied to reservoirs even before their natural energy drive is exhausted by primary depletion. Descriptive screening criteria for IOR methods are used to select the appropriate recovery technique according to the fluid and rock properties. This methodology helps in assessing the most suitable recovery process for field deployment of a candidate reservoir. However, the already published screening guidelines neither provide information about the expected reservoir performance nor suggest a set of project design parameters, which can be used towards the optimization of the process. In this study, artificial neural networks (ANN) are used to build a high-performance neuro-simulation tool for screening different improved oil recovery techniques: miscible injection (CO2 and N2), waterflooding and steam injection processes. The simulation tool consists of proxy models that implement a multilayer cascade feedforward back propagation network algorithm. The tool is intended to narrow the ranges of possible scenarios to be modeled using conventional simulation, reducing the extensive time and energy spent in dynamic reservoir modeling. A commercial reservoir simulator is used to generate the data to train and validate the artificial neural networks. The proxy models are built considering four different well patterns with different well operating conditions as the field design parameters. Different expert systems are developed for each well pattern. The screening networks predict oil production rate and cumulative oil production profiles for a given set of rock and fluid properties, and design parameters. The results of this study show that the networks are
Radiological study of the secondary reduction effect of early functional exercise on displaced intra-articular calcaneal fractures after internal compression fixation.

Science.gov (United States)

Chen, Wei; Liu, Bo; Lv, Hongzhi; Su, Yanling; Chen, Xiao; Zhu, Yanbin; Du, Chenguang; Zhang, Xiaolin; Zhang, Yingze

2017-09-01

Early post-operative exercise and weight-bearing activities are found to improve the functional recovery of patients with displaced intra-articular calcaneal fractures (DIACFs). We hypothesized that early functional exercise after surgery might have a secondary reduction effect on the subtalar joint, in particular the smaller fracture fragments that were not fixed firmly. A prospective study was conducted to verify this hypothesis. From December 2012 to September 2013, patients with unilateral DIACFs were enrolled and received a treatment consisting of percutaneous leverage and minimally invasive fixation. After surgery, patients in the study group started exercising on days two to three, using partial weight bearing starting week three, and full weight bearing starting week 12. Patients in the control group followed a conventional post-operative protocol of partial weight bearing after week six and full weight bearing after the bone healed. Computed tomography (CT) scanning was performed at post-operative day one, week four, week eight, and week 12 to reconstruct coronal, sagittal, and axial images, on which the maximal residual displacements of the fractures were measured. Function was evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) scoring scale at the 12th post-operative month. Twenty-eight patients in the study group and 32 in the control group were followed up for more than 12 months; their data were collected and used for the final analysis. Repeated-measures analysis of variance (ANOVA) of the maximal residual displacements of the fracture measured on CT images revealed significant differences between the study and the control groups. There were interaction effects between group and time point. Except for the first time point, the differences between the groups at all studied time points were significant. In the study group, the differences between all studied time points were significant. Strong correlations were observed between
TSC plasma halo simulation of a DIII-D vertical displacement episode

International Nuclear Information System (INIS)

Sayer, R.O.; Peng, Y.K.M.; Jardin, S.C.

1993-01-01

A benchmark of the Tokamak Simulation Code (TSC) plasma halo model has been achieved by calibration against a DIII-D vertical displacement episode (VDE) consisting of vertical drift, thermal quench and current quench. With a suitable halo surrounding the main plasma, the TSC predictions are in good agreement with experimental results for the plasma current decay, plasma trajectory, toroidal and poloidal vessel currents, and for the magnetic probe and flux loop values for the entire VDE. Simulations with no plasma halo yield much faster vertical motion and significantly worse agreement with the magnetics and flux loop data than do halo simulations. (author). 12 refs, 13 figs
Aromatic fluorine compounds. VI. Displacement of aryl fluorine in diazonium salts

Science.gov (United States)

Finger, G.C.; Oesterling, R.E.

1956-01-01

Several chlorofluorobenzenes have been isolated from the Schiemann synthesis of fluorobenzenes. These have been shown to be the products of two side reactions occurring during thermal decomposition of the dry benzenediazonium fluoborate salt containing coprecipitated sodium chloride, an unavoidable contaminant in large preparations involving the use of hydrochloric acid and sodium fluoborate. The major side reaction and its chloro product were unexpected; a unique displacement of fluorine ortho to the diazonium group was observed. Replacement of the diazo group with chlorine was the predicted side reaction which proved to be minor. Conditions causing the side reactions and the isolation and identification of the products are described.
Utilizing waste heat. Energy recovery options for trade and industry

Energy Technology Data Exchange (ETDEWEB)

Krieg, W

1988-08-01

The article shows options for efficient and low-cost thermal energy recovery. Heat recovery involves a number of problems, e.g. the type of waste heat, the uses of the energy recovered, and the best way of utilizing it. There is no generally applicable way of solving these problems. Some practical examples are presented. Economically efficient solutions require detailed technical knowledge as well as a good portion of creativity and imagination. (BR).
Reactor pressure vessel thermal annealing

International Nuclear Information System (INIS)

Lee, A.D.

1997-01-01

The steel plates and/or forgings and welds in the beltline region of a reactor pressure vessel (RPV) are subject to embrittlement from neutron irradiation. This embrittlement causes the fracture toughness of the beltline materials to be less than the fracture toughness of the unirradiated material. Material properties of RPVs that have been irradiated and embrittled are recoverable through thermal annealing of the vessel. The amount of recovery primarily depends on the level of the irradiation embrittlement, the chemical composition of the steel, and the annealing temperature and time. Since annealing is an option for extending the service lives of RPVs or establishing less restrictive pressure-temperature (P-T) limits; the industry, the Department of Energy (DOE) and the Nuclear Regulatory Commission (NRC) have assisted in efforts to determine the viability of thermal annealing for embrittlement recovery. General guidance for in-service annealing is provided in American Society for Testing and Materials (ASTM) Standard E 509-86. In addition, the American Society of Mechanical Engineers (ASME) Code Case N-557 addresses annealing conditions (temperature and duration), temperature monitoring, evaluation of loadings, and non-destructive examination techniques. The NRC thermal annealing rule (10 CFR 50.66) was approved by the Commission and published in the Federal Register on December 19, 1995. The Regulatory Guide on thermal annealing (RG 1.162) was processed in parallel with the rule package and was published on February 15, 1996. RG 1.162 contains a listing of issues that need to be addressed for thermal annealing of an RPV. The RG also provides alternatives for predicting re-embrittlement trends after the thermal anneal has been completed. This paper gives an overview of methodology and recent technical references that are associated with thermal annealing. Results from the DOE annealing prototype demonstration project, as well as NRC activities related to the

Tracking speckle displacement by double Kalman filtering

Institute of Scientific and Technical Information of China (English)

Donghui Li; Li Guo

2006-01-01

@@ A tracking technique using two sequentially-connected Kalman filter for tracking laser speckle displacement is presented. One Kalman filter tracks temporal speckle displacement, while another Kalman filter tracks spatial speckle displacement. The temporal Kalman filter provides a prior for the spatial Kalman filter, and the spatial Kalman filter provides measurements for the temporal Kalman filter. The contribution of a prior to estimations of the spatial Kalman filter is analyzed. An optical analysis system was set up to verify the double-Kalman-filter tracker's ability of tracking laser speckle's constant displacement.
Aquifer thermal energy storage - A feasibility study for large scale demonstration

Science.gov (United States)

Skinner, W. V.; Supkow, D. J.

Engineering procedures necessary for aquifer thermal energy storage (ATES), based on studies of the Magothy Aquifer on Long Island, NY, are presented, with chilled winter water pumped into the aquifer and reclaimed in summer months for air conditioning. The choice of aquifer involves necessary volume, flow rate, efficiency of thermal recovery, and avoidance of conflict with other users; utilization depends on choice of appropriate piping, heat exchangers, and well construction to prevent degradation of the aquifer. The methods employed to probe the Magothy for suitability are described, including drilling an asymmetric well cluster for observation, and 48 hr pumping and 8 hr recovery. Transmissivity was found to vary from 8,000 to 29,000 sq ft/day. A doublet well was then drilled and water withdrawn, chilled, and returned. Later withdrawal indicated a 46% thermal recovery, with computer models projecting 80% with additional cycling. The study verified the feasibility of ATES, which can be expanded with additional demand.
Displaced epithelium after liposuction for gynecomastia.

Science.gov (United States)

McLaughlin, Cristina S; Petrey, Chris; Grant, Shawn; Ransdell, Jill S; Reynolds, Carol

2011-08-01

The authors describe the case of a 36-year-old man with gynecomastia who was previously treated with liposuction of the breast for cosmetic purposes. Histologic examination of a subsequent excisional biopsy revealed nests of displaced epithelial cells in adipose tissue. Epithelial cell displacement is a well-known risk of core needle biopsies and fine-needle aspirations of breast lesions. However, to the authors' knowledge, epithelial displacement in gynecomastia after liposuction, mimicking invasive ductal carcinoma, has not previously been reported.
Effects of different cooling principles on thermal sensation and physiological responses

DEFF Research Database (Denmark)

Schellen, Lisje; Loomans, Marcel G.L.C.; De Wit, Martin H.

2013-01-01

Applying low exergy cooling concepts in the built environment allows reduction of use of high quality energy sources. Non-uniform thermal conditions, which may occur due to application of lowex systems, can result in discomfort. Two different cooling principles were studied: passive (through...... by the floor and mixing ventilation, and (6) AC-R-D-F; active cooling through radiation by the floor and displacement ventilation. Though all cases were designed at PMV ≈ 0, subjective data indicate significant differences between the cases. For the prediction of thermal sensation and thermal comfort under non...
Development of thermal actuators with multi-locking positions

Science.gov (United States)

Luo, J. K.; Zhu, Y.; Fu, Y. Q.; Flewitt, A. J.; Spearing, S. M.; Miao, J. M.; Milne, W. I.

2006-04-01

To reduce power consumption and operation temperature for micro-thermal actuators, metal-based micro-mechanical locks with multi-locking positions were analyzed and fabricated. The micro-locks consist of two or three U-shaped thermal actuators. The devices were made by a single mask process using electroplated Ni as the active material. Tests showed that the metal based thermal actuators deliver a maximum displacement of ~20µm at a much lower temperature than that of Si-based actuators. However Ni-actuators showed a severe back bending, which increases with increasing applied power. The temperature to initiate the back bending is as low as ~240°C. Back bending increases the distance between the two actuators, and leads to locking function failure. For practical application, Ni-based thermal actuators must be operated below 200°C.
Assessment of infiltration heat recovery and its impact on energy consumption for residential buildings

International Nuclear Information System (INIS)

Solupe, Mikel; Krarti, Moncef

2014-01-01

Highlights: • Five steady-state air infiltration heat recovery or IHR models are described and compared. • IHR models are incorporated within whole-building simulation analysis tool. • IHR can reduce the thermal loads of residential buildings by 5–30%. - Abstract: Infiltration is a major contributor to the energy consumption of buildings, particularly in homes where it accounts for one-third of the heating and cooling loads. Traditionally, infiltration is calculated independent of the building envelope performance, however, it has been established that a thermal coupling exists between the infiltration and conduction heat transfer of the building envelope. This effect is known as infiltration heat recovery (IHR). Experiments have shown that infiltration heat recovery can typically reduce the infiltration thermal load by 10–20%. Currently, whole-building energy simulation tools do not account for the effect of infiltration heat recovery on heating and cooling loads. In this paper, five steady-state IHR models are described to account for the thermal interaction between infiltration air and building envelope components. In particular, inter-model and experimental comparisons are carried out to assess the prediction accuracy of five IHR models. In addition, the results from a series of sensitivity analyses are presented, including an evaluation of the predictions for heating energy use associated with four audited homes obtained from whole-building energy simulation analysis with implemented infiltration heat recovery models. Experimental comparison of the IHR models reveal that the predictions from all the five models are consistent and are within 2% when 1-D flow and heat transfer conditions are considered. When implementing IHR models to a whole-building simulation environment, a reduction of 5–30% in heating consumption is found for four audited residential homes
Comparative environmental analysis of waste brominated plastic thermal treatments

International Nuclear Information System (INIS)

Bientinesi, M.; Petarca, L.

2009-01-01

The aim of this research activity is to investigate the environmental impact of different thermal treatments of waste electric and electronic equipment (WEEE), applying a life cycle assessment methodology. Two scenarios were assessed, which both allow the recovery of bromine: (A) the co-combustion of WEEE and green waste in a municipal solid waste combustion plant, and (B) the staged-gasification of WEEE and combustion of produced syngas in gas turbines. Mass and energy balances on the two scenarios were set and the analysis of the life cycle inventory and the life cycle impact assessment were conducted. Two impact assessment methods (Ecoindicator 99 and Impact 2002+) were slightly modified and then used with both scenarios. The results showed that scenario B (staged-gasification) had a potentially smaller environmental impact than scenario A (co-combustion). In particular, the thermal treatment of staged-gasification was more energy efficient than co-combustion, and therefore scenario B performed better than scenario A, mainly in the impact categories of 'fossil fuels' and 'climate change'. Moreover, the results showed that scenario B allows a higher recovery of bromine than scenario A; however, Br recovery leads to environmental benefits for both the scenarios. Finally the study demonstrates that WEEE thermal treatment for energy and matter recovery is an eco-efficient way to dispose of this kind of waste
Influence of displacement damage on deuterium and helium retention in austenitic and ferritic-martensitic alloys considered for ADS service

Energy Technology Data Exchange (ETDEWEB)

Voyevodin, V.N.; Karpov, S.A.; Kopanets, I.E.; Ruzhytskyi, V.V. [National Science Center “Kharkov Institute of Physics and Technology” Kharkov, 1, Akademicheskaya St., Kharkov, 61108 (Ukraine); Tolstolutskaya, G.D., E-mail: g.d.t@kipt.kharkov.ua [National Science Center “Kharkov Institute of Physics and Technology” Kharkov, 1, Akademicheskaya St., Kharkov, 61108 (Ukraine); Garner, F.A. [Radiation Effects Consulting, Richland, WA (United States)

2016-01-15

The behavior of ion-implanted hydrogen (deuterium) and helium in austenitic 18Cr10NiTi stainless steel, EI-852 ferritic steel and ferritic/martensitic steel EP-450 and their interaction with displacement damage were investigated. Energetic argon irradiation was used to produce displacement damage and bubble formation to simulate nuclear power environments. The influence of damage morphology and the features of radiation-induced defects on deuterium and helium trapping in structural alloys was studied using ion implantation, the nuclear reaction D({sup 3}He,p){sup 4}He, thermal desorption spectrometry and transmission electron microscopy. It was found in the case of helium irradiation that various kinds of helium-radiation defect complexes are formed in the implanted layer that lead to a more complicated spectra of thermal desorption. Additional small changes in the helium spectra after irradiation with argon ions to a dose of ≤25 dpa show that the binding energy of helium with these traps is weakly dependent on the displacement damage. It was established that retention of deuterium in ferritic and ferritic-martensitic alloys is three times less than in austenitic steel at damage of ∼1 dpa. The retention of deuterium in steels is strongly enhanced by presence of radiation damages created by argon ion irradiation, with a shift in the hydrogen release temperature interval of 200 K to higher temperature. At elevated temperatures of irradiation the efficiency of deuterium trapping is reduced by two orders of magnitude.
Pressurized Recuperator For Heat Recovery In Industrial High Temperature Processes

Directory of Open Access Journals (Sweden)

Gil S.

2015-09-01

Full Text Available Recuperators and regenerators are important devices for heat recovery systems in technological lines of industrial processes and should have high air preheating temperature, low flow resistance and a long service life. The use of heat recovery systems is particularly important in high-temperature industrial processes (especially in metallurgy where large amounts of thermal energy are lost to the environment. The article presents the process design for a high efficiency recuperator intended to work at high operating parameters: air pressure up to 1.2 MPa and temperature of heating up to 900°C. The results of thermal and gas-dynamic calculations were based on an algorithm developed for determination of the recuperation process parameters. The proposed technical solution of the recuperator and determined recuperation parameters ensure its operation under maximum temperature conditions.
Water displacement mercury pump

Science.gov (United States)

Nielsen, M.G.

1984-04-20

A water displacement mercury pump has a fluid inlet conduit and diffuser, a valve, a pressure cannister, and a fluid outlet conduit. The valve has a valve head which seats in an opening in the cannister. The entire assembly is readily insertable into a process vessel which produces mercury as a product. As the mercury settles, it flows into the opening in the cannister displacing lighter material. When the valve is in a closed position, the pressure cannister is sealed except for the fluid inlet conduit and the fluid outlet conduit. Introduction of a lighter fluid into the cannister will act to displace a heavier fluid from the cannister via the fluid outlet conduit. The entire pump assembly penetrates only a top wall of the process vessel, and not the sides or the bottom wall of the process vessel. This insures a leak-proof environment and is especially suitable for processing of hazardous materials.
Enhanced Oil Recovery from Oil-wet Carbonate Rock by Spontaneous Imbibition of Aqueous Surfactant Solutions

Energy Technology Data Exchange (ETDEWEB)

Standnes, Dag Chun

2001-09-01

The main theme of this thesis is an experimental investigation of spontaneous imbibition (SI) of aqueous cationic surfactant solution into oil-wet carbonate (chalk- and dolomite cores). The static imbibition process is believed to represent the matrix flow of oil and water in a fractured reservoir. It was known that aqueous solution of C{sub 12}-N(CH{sub 3}){sub 3}Br (C12TAB) was able to imbibe spontaneously into nearly oil-wet chalk material, but the underlying mechanism was not understood. The present work was therefore initiated, with the following objectives: (1) Put forward a hypothesis for the chemical mechanism underlying the SI of C12TAB solutions into oil-wet chalk material based on experimental data and (2) Perform screening tests of low-cost commercially available surfactants for their ability to displace oil by SI of water into oil-wet carbonate rock material. It is essential for optimal use of the surfactant in field application to have detailed knowledge about the mechanism underlying the SI process. The thesis also discusses some preliminary experimental results and suggests mechanisms for enhanced oil recovery from oil-wet carbonate rock induced by supply of thermal energy.
Mechanisms of microbial oil recovery by Clostridium acetobutylicum and Bacillus strain JF-2

Energy Technology Data Exchange (ETDEWEB)

Marsh, T.L.; Zhang, X.; Knapp, R.M.; McInerney, M.J.; Sharma, P.K.; Jackson, B.E.

1995-12-31

Core displacement experiments at elevated pressures were conducted to determine whether microbial processes are effective under conditions that simulate those found in an actual oil reservoir. The in-situ growth of Clostridium acetobutylicum and Bacillus strain JF-2 resulted in the recovery of residual oil. About 21 and 23% of the residual oil was recovered by C. acetobutylicum and Bacillus strain JF-2, respectively. Flooding cores with cell-free culture fluids of C. acetobutylicum with and without the addition of 50 mM acetone and 100 mM butanol did not result in the recovery of residual oil. Mathematical simulations showed that the amount of gas produced by the clostridial fermentation was not showed that the amount of gas produced by the clostridial fermentation was not sufficient to recover residual oil. Oil recovery by Bacillus strain JF-2 was highly correlated to surfactant production. A biosurfactant-deficient mutant of strain JF-2 was not capable of recovering residual oil. These data show that surfactant production is an important mechanism for microbially enhanced oil recovery. The mechanism for oil recovery by C. acetobutylicum is not understood at this time, but the production of acids, solvents, or gases alone cannot explain the observed increases in oil recovery by this organism.
High actuation properties of shape memory polymer composite actuator

International Nuclear Information System (INIS)

Basit, A; L’Hostis, G; Durand, B

2013-01-01

The shape memory polymers (SMPs) possess two shapes: permanent shape and temporary shape. This property leads to replacement of shape memory alloys by SMPs in various applications. In this work, two properties, namely structure activeness and the shape memory property of ‘controlled behavior composite material (CBCM)’ plate and its comparison with the conventional symmetrical composite plate (SYM), are studied. The SMPC plates (CBCM and SYM) are manufactured using epoxy resin with a thermal glass transition temperature (T g ) of 130 °C. The shape memory properties of these composites are investigated (under three-point bending test) and compared by deforming them to the same displacement. Three types of recoveries are conducted: unconstrained recovery, constrained recovery, and partial recovery under load. It is found that by coupling the structure activeness (due to its asymmetry) and its shape memory property, higher activated displacement is obtained during the unconstrained recovery. Also, at a lower recovery temperature (90 °C) than the fixing temperature, a recovery close to 100% is obtained for CBCM, whereas for SYM it is only 25%. During constrained recovery, CBCM produces five times larger recovery force than SYM. In addition, higher actuation properties are demonstrated by calculating recovered work and recovery percentages during partial recovery under load. (paper)
Study of elevated temperature design standard against thermal loads

International Nuclear Information System (INIS)

Kasahara, Naoto; Asayama, Tai; Morishita, Masaki

2001-01-01

Elevated temperature components must be designed against both pressure and thermal loads. In the case of sodium circuits of fast breeder reactors, a restriction from the pressure load becomes small because of the high boiling point of sodium. Design approaches for thermal loads (displacement-controlled) are compared with those against pressure loads (load-controlled). Considering differences between those two approaches, a concept of the elevated temperature design standard that takes the nature of thermal loads fully into account is proposed. This concept is a basis of load evaluation techniques and an inelastic analysis guide, that are being developed. Finally, problems and plans to realize the above concept are discussed. (author)
Prolonged displacement may compromise resilience in Eritrean mothers.

Science.gov (United States)

Almedom, Astier; Tesfamichael, Berhe; Mohammed, Zein; Mascie-Taylor, Nick; Muller, Jocelyn; Alemu, Zemui

2005-12-01

to assess the impact of prolonged displacement on the resilience of Eritrean mothers. an adapted SOC scale (short form) was administered. Complementary qualitative data were gathered from study participants' spontaneous reactions to and commentaries on the SOC scale. Displaced women's SOC scores were significantly less than those of the non-displaced: Mean = 54.84; SD = 6.48 in internally displaced person (IDP) camps, compared to non-displaced urban and rural/pastoralist: Mean = 48. 94, SD = 11.99; t = 3.831, p urban (non-displaced). Rural but traditionally mobile (pastoralist or transhumant) communities scored more or less the same as the urban non-displaced--i.e., significantly higher than those in IDP camps (p urban and pastoralist/transhumant groups were similar, while women in IDP camps were lower scoring--RR = .268, p < .001. The implications of these findings for health policy are critical. It is incumbent on the international health institutions including the World Health Organization and regional as well as local players to address the plight of internally displaced women, their families and communities in Eritrea and other places of dire conditions such as, for example Darfur in the Sudan.
Oil recovery from naturally fractured reservoirs by steam injection methods. Final report

Energy Technology Data Exchange (ETDEWEB)

Reis, J.C.; Miller, M.A.

1995-05-01

Oil recovery by steam injection is a proven, successful technology for nonfractured reservoirs, but has received only limited study for fractured reservoirs. Preliminary studies suggest recovery efficiencies in fractured reservoirs may be increased by as much as 50% with the application of steam relative to that of low temperature processes. The key mechanisms enhancing oil production at high temperature are the differential thermal expansion between oil and the pore volume, and the generation of gases within matrix blocks. Other mechanisms may also contribute to increased production. These mechanisms are relatively independent of oil gravity, making steam injection into naturally fractured reservoirs equally attractive to light and heavy oil deposits. The objectives of this research program are to quantify the amount of oil expelled by these recovery mechanisms and to develop a numerical model for predicting oil recovery in naturally fractured reservoirs during steam injection. The experimental study consists of constructing and operating several apparatuses to isolate each of these mechanisms. The first measures thermal expansion and capillary imbibition rates at relatively low temperature, but for various lithologies and matrix block shapes. The second apparatus measures the same parameters, but at high temperatures and for only one shape. A third experimental apparatus measures the maximum gas saturations that could build up within a matrix block. A fourth apparatus measures thermal conductivity and diffusivity of porous media. The numerical study consists of developing transfer functions for oil expulsion from matrix blocks to fractures at high temperatures and incorporating them, along with the energy equation, into a dual porosity thermal reservoir simulator. This simulator can be utilized to make predictions for steam injection processes in naturally-fractured reservoirs. Analytical models for capillary imbibition have also been developed.
Thermal stratification and fatigue stress analysis for pressurizer surge line

International Nuclear Information System (INIS)

Yu Xiaofei; Zhang Yixiong

2011-01-01

Thermal stratification of pressurizer surge line induced by the inside fluid results in the global bending moments, local thermal stresses, unexpected displacements and support loadings of the pipe system. In order to avoid a costly three-dimensional computation, a combined 1D/2D technique has been developed and implemented to analyze the thermal stratification and fatigue stress of pressurize surge line of QINSHAN Phase II Extension Nuclear Power Project in this paper, using the computer codes SYSTUS and ROCOCO. According to the mechanical analysis results of stratification, the maximum stress and cumulative usage factor are obtained. The results indicate that the stress and fatigue intensity considering thermal stratification satisfies RCC-M criterion. (authors)
Displaced and non-displaced Colombian children's evaluations of moral transgressions, retaliation, and reconciliation

Science.gov (United States)

Ardila-Rey, Alicia; Killen, Melanie; Brenick, Alaina

2015-01-01

In order to assess the effects of displacement and exposure to violence on children's moral reasoning, Colombian children exposed to minimal violence (non-displaced or low-risk) (N = 99) and to extreme violence (displaced or high-risk) (N = 94), evenly divided by gender, at 6-, 9-, and 12 - years of age, were interviewed regarding their evaluation of peer-oriented moral transgressions (hitting and not sharing toys). The vast majority of children evaluated moral transgressions as wrong. Group and age differences were revealed, however, regarding provocation and retaliation. Children who were exposed to violence, in contrast to those with minimum exposure, judged it more legitimate to inflict harm or deny resources when provoked and judged it more okay to retaliate for reasons of retribution. Surprisingly, and somewhat hopefully, all children viewed reconciliation as feasible. The results are informative regarding theories of morality, culture, and the effects of violence on children's social development. PMID:25722543
Identifying Time Periods of Minimal Thermal Gradient for Temperature-Driven Structural Health Monitoring

Directory of Open Access Journals (Sweden)

John Reilly

2018-03-01

Full Text Available Temperature changes play a large role in the day to day structural behavior of structures, but a smaller direct role in most contemporary Structural Health Monitoring (SHM analyses. Temperature-Driven SHM will consider temperature as the principal driving force in SHM, relating a measurable input temperature to measurable output generalized strain (strain, curvature, etc. and generalized displacement (deflection, rotation, etc. to create three-dimensional signatures descriptive of the structural behavior. Identifying time periods of minimal thermal gradient provides the foundation for the formulation of the temperature–deformation–displacement model. Thermal gradients in a structure can cause curvature in multiple directions, as well as non-linear strain and stress distributions within the cross-sections, which significantly complicates data analysis and interpretation, distorts the signatures, and may lead to unreliable conclusions regarding structural behavior and condition. These adverse effects can be minimized if the signatures are evaluated at times when thermal gradients in the structure are minimal. This paper proposes two classes of methods based on the following two metrics: (i the range of raw temperatures on the structure, and (ii the distribution of the local thermal gradients, for identifying time periods of minimal thermal gradient on a structure with the ability to vary the tolerance of acceptable thermal gradients. The methods are tested and validated with data collected from the Streicker Bridge on campus at Princeton University.
Identifying Time Periods of Minimal Thermal Gradient for Temperature-Driven Structural Health Monitoring.

Science.gov (United States)

Reilly, John; Glisic, Branko

2018-03-01

Temperature changes play a large role in the day to day structural behavior of structures, but a smaller direct role in most contemporary Structural Health Monitoring (SHM) analyses. Temperature-Driven SHM will consider temperature as the principal driving force in SHM, relating a measurable input temperature to measurable output generalized strain (strain, curvature, etc.) and generalized displacement (deflection, rotation, etc.) to create three-dimensional signatures descriptive of the structural behavior. Identifying time periods of minimal thermal gradient provides the foundation for the formulation of the temperature-deformation-displacement model. Thermal gradients in a structure can cause curvature in multiple directions, as well as non-linear strain and stress distributions within the cross-sections, which significantly complicates data analysis and interpretation, distorts the signatures, and may lead to unreliable conclusions regarding structural behavior and condition. These adverse effects can be minimized if the signatures are evaluated at times when thermal gradients in the structure are minimal. This paper proposes two classes of methods based on the following two metrics: (i) the range of raw temperatures on the structure, and (ii) the distribution of the local thermal gradients, for identifying time periods of minimal thermal gradient on a structure with the ability to vary the tolerance of acceptable thermal gradients. The methods are tested and validated with data collected from the Streicker Bridge on campus at Princeton University.

Displacement of location in illusory line motion.

Science.gov (United States)

Hubbard, Timothy L; Ruppel, Susan E

2013-05-01

Six experiments examined displacement in memory for the location of the line in illusory line motion (ILM; appearance or disappearance of a stationary cue is followed by appearance of a stationary line that is presented all at once, but the stationary line is perceived to "unfold" or "be drawn" from the end closest to the cue to the end most distant from the cue). If ILM was induced by having a single cue appear, then memory for the location of the line was displaced toward the cue, and displacement was larger if the line was closer to the cue. If ILM was induced by having one of two previously visible cues vanish, then memory for the location of the line was displaced away from the cue that vanished. In general, the magnitude of displacement increased and then decreased as retention interval increased from 50 to 250 ms and from 250 to 450 ms, respectively. Displacement of the line (a) is consistent with a combination of a spatial averaging of the locations of the cue and the line with a relatively weaker dynamic in the direction of illusory motion, (b) might be implemented in a spreading activation network similar to networks previously suggested to implement displacement resulting from implied or apparent motion, and (c) provides constraints and challenges for theories of ILM.
FUNCTIONAL OUTCOME OF INTERNAL FIXATION FOR DISPLACED INTRA-ARTICULAR CALCANEAL FRACTURE

Directory of Open Access Journals (Sweden)

Saket Jati

2016-12-01

functional outcome individually. However, these relationships were all weak to low. CONCLUSION A strong connection between preoperative Bohler’s angle and the injury severity of displaced intra-articular calcaneal fractures, but only postoperative Bohler’s angle factors were major relationship with the functional recovery.
Variable displacement alpha-type Stirling engine

Science.gov (United States)

Homutescu, V. M.; Bălănescu, D. T.; Panaite, C. E.; Atanasiu, M. V.

2016-08-01

The basic design and construction of an alpha-type Stirling engine with on load variable displacement is presented. The variable displacement is obtained through a planar quadrilateral linkage with one on load movable ground link. The physico-mathematical model used for analyzing the variable displacement alpha-type Stirling engine behavior is an isothermal model that takes into account the real movement of the pistons. Performances and power adjustment capabilities of such alpha-type Stirling engine are calculated and analyzed. An exemplification through the use of the numerical simulation was performed in this regard.
Transient thermal stresses in a transversely isotropic finite hollow circular cylinder due to arbitrary surface heat generations

International Nuclear Information System (INIS)

Sugano, Yoshihiro; Nakanishi, Takanori.

1980-01-01

The materials macroscopically regarded as anisotropic materials such as fiber-reinforced composite materials have become to be used for the structural elements at elevated temperature, and the studies on the problem of thermal stress in anisotropic bodies are carried out actively. The unsteady thermal stress in anisotropic finite circular cylinders has not been analyzed so far. In this study, the problem of unsteady thermal stress in an anisotropic finite circular cylinder having arbitrary surface heat generation in axial direction on the internal and external surfaces, and emitting heat from both ends and the internal and external surfaces, was analyzed. For the analysis of temperature distribution, generalized finite Fourier transformation and finite Hankel transformation were used, and thermal stress and thermal displacement were analyzed by the use of the stress function of Singh. By adopting the function used for the transformation nucleus in generalized finite Fourier transformation as the stress function, the analysis was made without separating symmetric and opposite symmetric problems. Numerical calculation was carried out on the basis of the analytical results, and the effects of the anisotropy in thermal conductivity, Young's modulus and linear expansion on unsteady temperature distribution, thermal stress and thermal displacement were quantitatively examined. (Kako, I.)
Managing Injected Water Composition To Improve Oil Recovery: A Case Study of North Sea Chalk Reservoirs

DEFF Research Database (Denmark)

Zahid, Adeel; Shapiro, Alexander; Stenby, Erling Halfdan

2012-01-01

of the temperature dependence of the oil recovery indicated that the interaction of the ions contained in brine with the rock cannot be the only determining mechanism of enhanced recovery. We observed no substitution of Ca2+ ions with Mg2+ ions at high temperatures for both rocks. Not only the injection brine......In recent years, many core displacement experiments of oil by seawater performed on chalk rock samples have reported SO42–, Ca2+, and Mg2+ as potential determining ions for improving oil recovery. Most of these studies were carried out with outcrop chalk core plugs. The objective of this study...... is to investigate the potential of the advanced waterflooding process by carrying out experiments with reservoir chalk samples. The study results in a better understanding of the mechanisms involved in increasing the oil recovery with potential determining ions. We carried out waterflooding instead of spontaneous...
Feasibility analysis of a small-scale ORC energy recovery system for vehicular application

International Nuclear Information System (INIS)

Capata, Roberto; Toro, Claudia

2014-01-01

Highlights: • We analyzed the feasibility of an “on-board” ORC recovery system to power auxiliaries. • Performance of the ORC cycle has been simulated with CAMEL-Pro™. • Several relevant ORC components have been designed. • Approximate characteristics dimensions of HRSG and evaporator have been calculated and a preliminary layout provided. • The evaluation of a possible assembling of the system has been developed. - Abstract: This paper analyses the feasibility of an “on-board” innovative and patented ORC recovery system. The vehicle thermal source can be either a typical diesel engine (1400 cc) or a small gas turbine set (15–30 kW). The sensible heat recovered from the exhaust gases feeds the energy recovery system that can produce sufficient extra power to sustain the conditioning system and other auxiliaries. The concept is suitable for all types of thermally propelled vehicles, but it is studied here for automotive applications. The characteristics of the organic cycle-based recovery system are discussed, and a preliminary design of the main components, such as the heat recovery exchanger, the evaporator and the pre-heater is presented. The main challenge are the imposed size and weight limitations that require a particular design for this compact recovery system. A possible system layout is analyzed and the requirements for a prototypal application are investigated
Energy recovery from municipal solid wastes in Italy: Actual study and perspective for future

International Nuclear Information System (INIS)

Brunetti, N.; Ciampa, F.; De Cecco, C.

1992-01-01

Materials and energy recovery from municipal solid wastes (MSW) and assimilable waste, and their re-use is one of strong points of current regulations and tendencies, both at the national and at community level in Europe. In Italy, the interest in energy recovery from renewable sources has been encouraged by energy-savings law which included financial incentives for thermal plant building if low grade fuels such as MSW were employed. New electric power prices imposed by Italian Electric Power Authority, ENEL, encourage energy recovery from waste burners. This paper aims to point out the present state of energy recovery from wastes in Italy, trends and prospects to satisfy, with new plants, the need for waste thermal destruction and part of the demand for energy in the different Italian regions: only about 10% of MSW are burned and just a small percentage of the estimated amount of recoverable energy (2 MTOE/y) is recuperated. Different technological cycles are discussed: incineration of untreated wastes and energy recovery; incineration (or gasification) of RDF (refuse derived fuels) and heat-electricity co-generation; burning of RDF in industrial plants, in addition to other fuels
Neutron displacement damage cross sections for SiC

International Nuclear Information System (INIS)

Huang Hanchen; Ghoniem, N.

1993-01-01

Calculations of neutron displacement damage cross sections for SiC are presented. We use Biersack and Haggmark's empirical formula in constructing the electronic stopping power, which combines Lindhard's model at low PKA energies and Bethe-Bloch's model at high PKA energies. The electronic stopping power for polyatomic materials is computed on the basis of Bragg's Additivity Rule. A continuous form of the inverse power law potential is used for nuclear scattering. Coupled integro-differential equations for the number of displaced atoms j, caused by PKA i, are then derived. The procedure outlined above gives partial displacement cross sections, displacement cross sections for each specie of the lattice, and for each PKA type. The corresponding damage rates for several fusion and fission neutron spectra are calculated. The stoichiometry of the irradiated material is investigated by finding the ratio of displacements among various atomic species. The role of each specie in displacing atoms is also investigated by calculating the fraction of displacements caused by each PKA type. The study shows that neutron displacement damage rates of SiC in typical magnetic fusion reactor first walls will be ∝10-15 dpa MW -1 m 2 ; in typical lead-protected inertial confinement fusion reactor first walls they will be ∝15-20 dpa MW -1 m 2 . For fission spectra, we find that the neutron displacement damage rate of SiC is ∝74 dpa per 10 27 n/m 2 in FFTF, ∝39 dpa per 10 27 n/m 2 in HFIR, and 25 dpa per 10 27 n/m 2 in NRU. Approximately 80% of displacement atoms are shown to be of the carbon-type. (orig.)
Asymmetric SOL Current in Vertically Displaced Plasma

Science.gov (United States)

Cabrera, J. D.; Navratil, G. A.; Hanson, J. M.

2017-10-01

Experiments at the DIII-D tokamak demonstrate a non-monotonic relationship between measured scrape-off layer (SOL) currents and vertical displacement event (VDE) rates with SOL currents becoming largely n=1 dominant as plasma is displaced by the plasma control system (PCS) at faster rates. The DIII-D PCS is used to displace the magnetic axis 10x slower than the intrinsic growth time of similar instabilities in lower single-null plasmas. Low order (n VDE instabilities observed when vertical control is disabled. Previous inquiry shows VDE asymmetry characterized by SOL current fraction and geometric parameters of tokamak plasmas. We note that, of plasmas displaced by the PCS, short displacement time scales near the limit of the PCS temporal control appear to result in larger n=1/n=2 asymmetries. Work supported under USDOE Cooperative Agreement DE-FC02-04ER54698 and DE-FG02-04ER54761.
Internal displacement in Colombia: Fifteen distinguishing features.

Science.gov (United States)

Shultz, James M; Ceballos, Ángela Milena Gómez; Espinel, Zelde; Oliveros, Sofia Rios; Fonseca, Maria Fernanda; Florez, Luis Jorge Hernandez

2014-01-01

This commentary aims to delineate the distinguishing features of conflict-induced internal displacement in the nation of Colombia, South America. Even as Colombia is currently implementing a spectrum of legal, social, economic, and health programs for "victims of armed conflict," with particular focus on internally displaced persons (IDPs), the dynamics of forced migration on a mass scale within this country are little known beyond national borders. The authors of this commentary are embarking on a global mental health research program in Bogota, Colombia to define best practices for reaching the displaced population and implementing sustainable, evidence-based screening and intervention for common mental disorders. Presenting the defining characteristics of internal displacement in Colombia provides the context for our work and, more importantly, conveys the compelling and complex nature of this humanitarian crisis. We attempt to demonstrate Colombia's unique position within the global patterning of internal displacement.
Investigation of Multiscale and Multiphase Flow, Transport and Reaction in Heavy Oil Recovery Processes

Energy Technology Data Exchange (ETDEWEB)

Yortsos, Yanis C.

2002-10-08

In this report, the thrust areas include the following: Internal drives, vapor-liquid flows, combustion and reaction processes, fluid displacements and the effect of instabilities and heterogeneities and the flow of fluids with yield stress. These find respective applications in foamy oils, the evolution of dissolved gas, internal steam drives, the mechanics of concurrent and countercurrent vapor-liquid flows, associated with thermal methods and steam injection, such as SAGD, the in-situ combustion, the upscaling of displacements in heterogeneous media and the flow of foams, Bingham plastics and heavy oils in porous media and the development of wormholes during cold production.
Venezuela-MEM/USA-DOE Fossil Energy Report IV-11: Supporting technology for enhanced oil recovery - EOR thermal processes

Energy Technology Data Exchange (ETDEWEB)

Venezuela

2000-04-06

This report contains the results of efforts under the six tasks of the Tenth Amendment anti Extension of Annex IV, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Energy Agreement. This report is presented in sections (for each of the six Tasks) and each section contains one or more reports that were prepared to describe the results of the effort under each of the Tasks. A statement of each Task, taken from the Agreement Between Project Managers, is presented on the first page of each section. The Tasks are numbered 68 through 73. The first through tenth report on research performed under Annex IV Venezuela MEM/USA-DOE Fossil Energy Report Number IV-1, IV-2, IV-3, IV-4, IV-5, IV-6, IV-7, IV-8, IV-9, IV-10 contain the results of the first 67 Tasks. These reports are dated April 1983, August 1984, March 1986, July 1987, November 1988, December 1989, October 1991, February 1993, March 1995, and December 1997, respectively.
Force transmissibility versus displacement transmissibility

Science.gov (United States)

Lage, Y. E.; Neves, M. M.; Maia, N. M. M.; Tcherniak, D.

2014-10-01

It is well-known that when a single-degree-of-freedom (sdof) system is excited by a continuous motion of the foundation, the force transmissibility, relating the force transmitted to the foundation to the applied force, equals the displacement transmissibility. Recent developments in the generalization of the transmissibility to multiple-degree-of-freedom (mdof) systems have shown that similar simple and direct relations between both types of transmissibility do not appear naturally from the definitions, as happens in the sdof case. In this paper, the authors present their studies on the conditions under which it is possible to establish a relation between force transmissibility and displacement transmissibility for mdof systems. As far as the authors are aware, such a relation is not currently found in the literature, which is justified by being based on recent developments in the transmissibility concept for mdof systems. Indeed, it does not appear naturally, but the authors observed that the needed link is present when the displacement transmissibility is obtained between the same coordinates where the applied and reaction forces are considered in the force transmissibility case; this implies that the boundary conditions are not exactly the same and instead follow some rules. This work presents a formal derivation of the explicit relation between the force and displacement transmissibilities for mdof systems, and discusses its potential and limitations. The authors show that it is possible to obtain the displacement transmissibility from measured forces, and the force transmissibility from measured displacements, opening new perspectives, for example, in the identification of applied or transmitted forces. With this novel relation, it becomes possible, for example, to estimate the force transmissibility matrix with the structure off its supports, in free boundary conditions, and without measuring the forces. As far as force identification is concerned, this
The Chinese Export Displacement Effect Revisited

DEFF Research Database (Denmark)

Elleby, Christian; Yu, Wusheng; Yu, Qian

China’s global export share has increased dramatically over the past decades. This development has prompted an empirical literature on whether Chinese exports displace those originated from elsewhere in various destination markets. In this paper we focus on the growth of China’s exports to the East...... African Community (EAC) countries and show how it has affected exports from the European Union (EU) to the EAC. Our main contribution to the literature on the displacement effect of Chinese exports is a set of total and relative displacement estimates based on different specifications of the gravity model...... where we control for country-year fixed effects so as to avoid the “gold medal mistake” of not accounting for time varying “multilateral resistance”. Our findings do not support the hypothesis that Chinese exports have displaced exports from other countries in general. Nor do they support the hypothesis...
The Three Gorges: the unexamined toll of development-induced displacement

Directory of Open Access Journals (Sweden)

Martin Stein

1998-04-01

Full Text Available In China, the context of forced displacement in its broadest sense centres on four issues: (1 coercive displacement for development; (2 political persecution resulting in controlled displacement; (3 massive labour dislocations; and (4 disaster-induced displacement. This article looks at the role of the state in displacement, focusing on the first of these issues: development-induced displacement.
Transport infrastructure monitoring: Testing of the NIODIM optical displacement monitoring system at the Sihlhochstrasse bridge in Zürich, Switzerland.

Science.gov (United States)

Hagene, J. K.

2012-04-01

night. The results with regards to short duration peaks is in line with the expectations namely within 1 mm displacement. However, a larger, long time constant displacement was registered during a certain time frame before noon on sunny days. A displacement of more than 10 mm was registered for a time interval in the order of one hour or more. This larger displacement decreased and the displacement was back on an even slower time-of-day, periodic looking displacement variation. If we disregards the larger "before noon" displacement the long time constant displacement is in the order of 2-3 mm one sunny day and in the order of 5 mm the second sunny day. The above results have been analysed with regards to different contributions to the long time constant displacement and three candidate causes have been targeted; thermal effects in the mounting brackets, thermal effects related to the pillar and thermal effects in the bridge deck. The time-of-day periodic displacements (2-5 mm) is most likely due to thermal effects in the bridge as a whole or the bridge deck. On the other hand the larger displacements (>10mm), around 1 hour duration before noon, could be caused by the mounting brackets or possibly the pillar. Both the pillar and the camera with mounting brackets of a temporary nature were exposed to direct sunlight in the affected time interval. However, we have not been able to fully explain the displacement seen based on the pillar and the mounting brackets, but we doubt it could be caused by bridge movement alone. From a development project point of view the tests have been successful; we have both learned some new lessons and demonstrated that the system works not to mention that we have demonstrated for the general public passing by in Zürich that scientists are also able to solve practical problems and cross rivers when required. Acknowledgement: The research leading to these results has received funding from the European Community's Seventh Framework Programme
Thermal structure of the Western Indian Ocean during the southwest monsoon, 1983

Digital Repository Service at National Institute of Oceanography (India)

Sarma, Y.V.B.; Sarma, M.S.S.; Rao, L.V.G.

The thermal structure and the variability of heat content of the upper 400 m of the Western Indian Ocean were examined using the expendable bathythermograph (XBT) data collected onboard RV Sagar Kanya during July-August, 1983. Vertical displacement...
Saskatchewan combustion recovery an operational success

Energy Technology Data Exchange (ETDEWEB)

1967-12-04

Mobil Oil Co.'s in-situ combustion recovery project in the Battrum heavy oil field in SW. Saskatchewan is an operational success, but not a profit-making venture so far. Some of the details resulting from a discussion with the senior project engineer are discussed. It is explained that 100% displacement efficiency is attained in the burned zone by way of fluid convection resulting from heat conduction. Reasons for selecting the Battrum reservoir are also considered. The pilot project currently being conducted is intended to determine information on the following factors: effect of productivity, injectivity index data, air-oil ratio performance, distribution of injected gas, ignition characteristics, and sweep efficiency. The largest problems are associated with equipment, well completions, and handling of produced fluids.
Thermal flexural analysis of cross-ply laminated plates using trigonometric shear deformation theory

Directory of Open Access Journals (Sweden)

Yuwaraj Marotrao Ghugal

Full Text Available Thermal stresses and displacements for orthotropic, two-layer antisymmetric, and three-layer symmetric square cross-ply laminated plates subjected to nonlinear thermal load through the thickness of laminated plates are presented by using trigonometric shear deformation theory. The in-plane displacement field uses sinusoidal function in terms of thickness co-ordinate to include the shear deformation effect. The theory satisfies the shear stress free boundary conditions on the top and bottom surfaces of the plate. The present theory obviates the need of shear correction factor. Governing equations and boundary conditions of the theory are obtained using the principle of virtual work. The validity of present theory is verified by comparing the results with those of classical plate theory and first order shear deformation theory and higher order shear deformation theory.
Thermal reactor safety

International Nuclear Information System (INIS)

1980-06-01

Information is presented concerning new trends in licensing; seismic considerations and system structural behavior; TMI-2 risk assessment and thermal hydraulics; statistical assessment of potential accidents and verification of computational methods; issues with respect to improved safety; human factors in nuclear power plant operation; diagnostics and activities in support of recovery; LOCA transient analysis; unresolved safety issues and other safety considerations; and fission product transport

Thermal reactor safety

Energy Technology Data Exchange (ETDEWEB)

1980-06-01

Information is presented concerning new trends in licensing; seismic considerations and system structural behavior; TMI-2 risk assessment and thermal hydraulics; statistical assessment of potential accidents and verification of computational methods; issues with respect to improved safety; human factors in nuclear power plant operation; diagnostics and activities in support of recovery; LOCA transient analysis; unresolved safety issues and other safety considerations; and fission product transport.
Displaced Homemakers: Vo-Tech Workshop Guide.

Science.gov (United States)

Peltier, Wanda Jo

Written for displaced homemaker programs in vocational-technical schools, this curriculum contains material designed so that instructors can prepare student manuals appropriate to almost any educational support situation for displaced homemakers. An overview provides information on special needs groups, curriculum use, and resources and sample…
5 CFR 330.706 - Notification of displaced employees.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Notification of displaced employees. 330... RECRUITMENT, SELECTION, AND PLACEMENT (GENERAL) Interagency Career Transition Assistance Plan for Displaced Employees § 330.706 Notification of displaced employees. (a) In addition to meeting the requirements of...
Local behaviour of negative thermal expansion materials

International Nuclear Information System (INIS)

Fornasini, P.; Dalba, G.; Grisenti, R.; Purans, J.; Vaccari, M.; Rocca, F.; Sanson, A.

2006-01-01

EXAFS can represent a powerful probe of the local behaviour of negative thermal expansion (NTE) materials, thanks to the possibility of measuring the expansion of selected inter-atomic bonds and the perpendicular relative atomic displacements. The effectiveness of EXAFS for NTE studies is illustrated by a comparison of results recently obtained on germanium, CuCl and the cuprites Cu 2 O and Ag 2 O
40 CFR 205.153 - Engine displacement.

Science.gov (United States)

2010-07-01

..., in accordance with American Society for Testing Materials (ASTM) E 29-67. (b) For rotary engines... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Engine displacement. 205.153 Section... TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Motorcycles § 205.153 Engine displacement. (a) Engine...
Dissolved oxygen detection by galvanic displacement-induced

Indian Academy of Sciences (India)

Dissolved oxygen detection by galvanic displacement-induced graphene/silver nanocomposite ... dissolved oxygen (DO) detection based on a galvanic displacement synthesized reduced graphene oxide–silver nanoparticles ... Current Issue
Performance of stratified thermal-storage system for Oliver Springs Elementary School. Progress report

Energy Technology Data Exchange (ETDEWEB)

Reid, R.L.; Bedinger, A.F.G.

1981-01-01

A progress report is given on the performance of a stratified thermal storage system coupled with a heat recovery refrigeration machine designed to provide space heating, cooling and service water heating. Water storage tanks utilizing a flexible membrane to resist temperature blending will be used as the thermal storage element. The two design goals of the heat recovery and thermal energy storage system are (1) to minimize the need to purchase energy for space heating and cooling and water heating and (2) to minimize electrical demand. An automatic data acquisition system will be used for system performance and data gathering. Data collection is expected to begin in September, 1981.
Test and analysis of thermal ratcheting deformation for 316L stainless steel cylindrical structure

International Nuclear Information System (INIS)

Lee, Hyeong Yeon; Kim, Jong Bum; Lee, Jae Han

2002-01-01

In this study, the progressive inelastic deformation, so called, thermal ratchet phenomenon which can occur in high temperature structures of liquid metal simulated with thermal ratchet structural test facility and 316L stainless steel test cylinder. The thermal ratchet deformation at the reactor baffle cylinder of the liquid metal reactor can occur due to the moving temperature distribution along the axial direction as the sodium free surface moves up and down under the cyclic heat-up and cool-down transients. The ratchet deformation was measured with the laser displacement sensor and LVDTs after cooling the structural specimen which is heated up to 550 degree C with steep temperature gradients along the axial direction. The temperature distribution of the test cylinder along the axial direction was measured with 28 channels of thermocouples and was used for the ratchet analysis. The thermal ratchet deformation was analyzed with the constitutive equation of nonlinear combined hardening model which was implemented as ABAQUS user subroutine and the analysis results were compared with those of the test. Thermal ratchet load was applied 9 times and the residual displacement after 9 cycles of thermal load was measured to be 1.79 mm. The ratcheting deformation shapes obtained by the analysis with the combined hardening model were in reasonable agreement with those of the structural tests
Transient thermal stresses in a transversely isotropic finite composite hollow circular cylinder due to arbitrary surface heat-generations and surrounding temperatures

International Nuclear Information System (INIS)

Sugano, Y.

1981-01-01

An exact solution is given for the temperature distribution, the thermal stresses and displacements in a transversely isotropic finite composite hollow circular cylinder composed of two distinct cylindrical laminae. The temperature field is determined by using of the Laplace transform and the finite Fourier-cosine transform, respectively, with respect to time and axial coordinate included in the governing equation and the associated thermal stresses and displacements are analvsed by the use of a set of stress functions closely related to the Love's function valid for the axisymmetric isothermal problem of isotropic bodies. (orig.)
A comparison of two low grade heat recovery options

International Nuclear Information System (INIS)

Walsh, Conor; Thornley, Patricia

2013-01-01

Low grade heat (LGH) recovery is one way of increasing industrial energy efficiency and reducing associated greenhouse gas emissions. The organic Rankine cycle (ORC) and condensing boiler are two options that can be used to recover low grade heat ( 2 annually, but the high carbon intensity of the coking process means this has a negligible influence (<1%) on the overall process lifecycle impacts. However, if the electricity generated offsets the external purchasing of electricity this results in favourable economic payback periods of between 3 and 6 years. The operation of a condensing boiler within a woodchip boiler reduces the fuel required to achieve an increased thermal output. The thermal efficiency gains reduce the lifecycle impacts by between 11 and 21%, and reflect payback periods as low as 1.5–2 years, depending on the condenser type and wood supply chain. The two case studies are used to highlight the difficulty in identifying LGH recovery solutions that satisfy multiple environmental, economic and wider objectives
French studies on the thermal effluents of electric power plants

International Nuclear Information System (INIS)

Dezes-Cadiere, H.

1976-01-01

This report presents a synthesis of studies made in France in the thermal effluent field: thermal power plant cooling systems, transfer and dispersion of thermal effluents in the receptive media, effects of thermal effluents on water physicochemistry and biochemistry, effects of thermal effluents on aquatic ecosystems, and, possibilities of waste heat recovery with the view of utilization in agriculture, aquaculture and district heating. A catalogue of French organizations working or having data on thermal effluents is presented, as also an alphabetical list of the contacted persons. A bibliography of French documents concerning the previously mentioned studies is finally given (193 refs.) [fr
Research on the porous flow of the mechanism of viscous-elastic fluids displacing residual oil droplets in micro pores

Science.gov (United States)

Dong, Guanyu

2018-03-01

In order to analyze the microscopic stress field acting on residual oil droplets in micro pores, calculate its deformation, and explore the hydrodynamic mechanism of viscous-elastic fluids displacing oil droplets, the viscous-elastic fluid flow equations in micro pores are established by choosing the Upper Convected Maxwell constitutive equation; the numerical solutions of the flow field are obtained by volume control and Alternate Direction Implicit methods. From the above, the velocity field and microscopic stress field; the forces acting on residual oil droplets; the deformations of residual oil droplets by various viscous-elastic displacing fluids and at various Wiesenberg numbers are calculated and analyzed. The result demonstrated that both the normal stress and horizontal force acting on the residual oil droplets by viscous-elastic fluids are much larger compared to that of inelastic fluid; the distribution of normal stress changes abruptly; under the condition of the same pressure gradient in the system under investigation, the ratio of the horizontal forces acting on the residual oil droplets by different displacing fluids is about 1:8:20, which means that under the above conditions, the driving force on a oil droplet is 20 times higher for a viscous-elastic fluid compared to that of a Newtonian Fluid. The conclusions are supportive of the mechanism that viscous-elastic driving fluids can increase the Displacement Efficiency. This should be of help in designing new chemicals and selecting Enhanced Oil Recovery systems.
Modeling the Impact of Deformation on Unstable Miscible Displacements in Porous Media

Science.gov (United States)

Santillán, D.; Cueto-Felgueroso, L.

2014-12-01

Coupled flow and geomechanics is a critical research challenge in engineering and the geosciences. The simultaneous flow of two or more fluids with different densities or viscosities through deformable media is ubiquitous in environmental, industrial, and biological processes, including the removal of non-aqueous phase liquids from underground water bodies, the geological storage of CO2, and current challenges in energy technologies, such as enhanced geothermal systems, unconventional hydrocarbon resources or enhanced oil recovery techniques. Using numerical simulation, we study the interplay between viscous-driven flow instabilities (viscous fingering) and rock mechanics, and elucidate the structure of the displacement patterns as a function of viscosity contrast, injection rate and rock mechanical properties. Finally, we discuss the role of medium deformation on transport and mixing processes in porous media.
Displacement in new economy labor markets: Post-displacement wage loss in high tech versus low tech cities.

Science.gov (United States)

Davis, Daniel J; Rubin, Beth A

2016-11-01

While scholars and politicians tout education as the salve to employment disruptions, we argue that the geography of the new economy, and the social closure mechanisms that geography creates, may be just as important as individuals' characteristics for predicting post-displacement wage loss (or gain). We use data from the 2012 Displaced Workers ement of the Current Population Survey and from the 2010 United States Census to test hypotheses linking local labor markets in different industrial contexts to post-displacement wage loss. Our results point to age as a closure mechanism, and to the partially protective effect of education in high-tech versus low-tech economic sectors. This study is the first to use national level data to examine how employment in high-tech cities influences post-displacement wages. These findings are relevant both for theorizing about the new economy and for public policy. Copyright © 2016 Elsevier Inc. All rights reserved.
Ductile fracture estimation of reactor pressure vessel under thermal shock

International Nuclear Information System (INIS)

Takahashi, Jun; Sakai, Shinsuke; Okamura, Hiroyuki

1990-01-01

This paper presents a new scheme for the estimation of unstable ductile fracture of a reactor pressure vessel under thermal shock conditions. First, it is shown that the bending moment applied to the cracked section can be evaluated by considering the plastic deformation of the cracked section and the thermal deformation of the shell. As the contribution of the local thermal stress to the J-value is negligible, the J-value under thermal shock can be easily evaluated by using fully plastic solutions for the cracked part. Next, the phenomena of ductile fracture under thermal shock are expressed on the load-versus-displacement diagram which enables us to grasp the transient phenomena visually. In addition, several parametrical surveys are performed on the above diagram concerning the variation of (1) thermal shock conditions, (2) initial crack length, and (3) J-resistance curve (i.e. embrittlement by neutron irradiation). (author)
Polymer as permeability modifier in porous media for enhanced oil recovery

Science.gov (United States)

Parsa, Shima; Weitz, David

2017-11-01

We use confocal microscopy to directly visualize the changes in morphology and mobilization of trapped oil ganglia within a 3D micromodel of porous media upon polymer flooding. Enhanced oil recovery is achieved in polymer flooding with large molecular weight at concentrations close or higher than a critical concentration of polymer. We also measure the fluctuations of the velocity of the displacing fluid and show that the velocities change upon polymer flooding in the whole medium. The changes in the fluid velocities are heterogeneous and vary in different pores, hence only providing enough pressure gradient across a few of the trapped oil ganglia and mobilize them. Our measurements show that polymer flooding is an effective method for enhancing oil recovery due to retention of polymer on the solid surfaces and changing the resistances of the available paths to water.
Modeling the Impact of Fracture Growth on Fluid Displacements in Deformable Porous Media

Science.gov (United States)

Santillán, D.; Cueto-Felgueroso, L.; Juanes, R.

2015-12-01

Coupled flow and geomechanics is a critical research challenge in engineering and the geosciences. The flow of a fluid through a deformable porous media is present in manyenvironmental, industrial, and biological processes,such as the removal of pollutants from underground water bodies, enhanced geothermal systems, unconventional hydrocarbon resources or enhanced oil recovery techniques. However, the injection of a fluid can generate or propagate fractures, which are preferential flow paths. Using numerical simulation, we study the interplay between injection and rock mechanics, and elucidate fracture propagation as a function of injection rate, initial crack topology and mechanical rock properties. Finally, we discuss the role of fracture growth on fluid displacements in porous media. Figure: An example of fracture (in red) propagated in a porous media (in blue)
A review on applications of nanotechnology in the enhanced oil recovery part B: effects of nanoparticles on flooding

Science.gov (United States)

Cheraghian, Goshtasp; Hendraningrat, Luky

2016-11-01

Chemical flooding is of increasing interest and importance due to high oil prices and the need to increase oil production. Research in nanotechnology in the petroleum industry is advancing rapidly, and an enormous progress in the application of nanotechnology in this area is to be expected. The nanotechnology has been widely used in several other industries, and the interest in the oil industry is increasing. Nanotechnology has the potential to profoundly change enhanced oil recovery and to improve mechanism of recovery, and it is chosen as an alternative method to unlock the remaining oil resources and applied as a new enhanced oil recovery method in last decade. This paper therefore focuses on the reviews of the application of nanotechnology in chemical flooding process in oil recovery and reviews the applications of nanomaterials for improving oil recovery that have been proposed to explain oil displacement by polymer flooding within oil reservoirs, and also this paper highlights the research advances of polymer in oil recovery. Nanochemical flooding is an immature method from an application point of view.
Study on CO{sub 2} Recovery System Design in Supercritical CO{sub 2} Cycle for SFR Application

Energy Technology Data Exchange (ETDEWEB)

Kim, Min Seok; Jung, Hwa-Young; Lee, Jeong Ik [KAIST, Daejeon (Korea, Republic of)

2016-10-15

As a part of Sodium-cooled Fast Reactor (SFR) development in Korea, the supercritical CO{sub 2} (S-CO{sub 2}) Brayton cycle is considered as an alternative power conversion system to eliminate sodium-water reaction (SWR) when the current conventional steam Rankine cycle is utilized with SFR. The parasitic loss caused by the leakage flow should be minimized since this greatly influences the cycle efficiency. Thus, a simple model for estimating the critical flow in a turbo-machinery seal was developed to predict the leakage flow rate and calculate the required total mass of working fluid in a S-CO{sub 2} power system to minimize the parasitic loss. In this work, study on CO{sub 2} recovery system design was conducted by finding the suitable recovery point with the developed simple CO{sub 2} critical flow model and sensitivity analysis was performed on the power system performance with respect to multiple CO{sub 2} recovery process options. The study of a CO{sub 2} recovery system design was conducted to minimize the thermal efficiency losses caused by CO{sub 2} inventory recovery system. For the first step, the configuration of a seal was selected. A labyrinth seal has suitable features for the S-CO{sub 2} power cycle application. Then, thermal efficiency losses with different CO{sub 2} leak rate and recovery point were evaluated. To calculate the leak rate in turbo-machinery by using the developed CO{sub 2} critical flow model, the conditions of storage tank is set to be closer to the recovery point. After modifying the critical flow model appropriately, total mass flow rate of leakage flow was calculated. Finally, the CO{sub 2} recovery system design work was performed to minimize the loss of thermal efficiency. The suggested system is not only simple and intuitive but also has relatively very low additional work loss from the compressor than other considered systems. When each leak rate is set to the conventional leakage rate of 1 kg/s per seal, the minimum and
Advanced regenerative heat recovery system

Science.gov (United States)

Prasad, A.; Jasti, J. K.

1982-02-01

A regenerative heat recovery system was designed and fabricated to deliver 1500 scfm preheated air to a maximum temperature of 1600 F. Since this system is operating at 2000 F, the internal parts were designed to be fabricated with ceramic materials. This system is also designed to be adaptable to an internal metallic structure to operate in the range of 1100 to 1500 F. A test facility was designed and fabricated to test this system. The test facility is equipped to impose a pressure differential of up to 27 inches of water column in between preheated air and flue gas lines for checking possible leakage through the seals. The preliminary tests conducted on the advanced regenerative heat recovery system indicate the thermal effectiveness in the range of 60% to 70%. Bench scale studies were conducted on various ceramic and gasket materials to identify the proper material to be used in high temperature applications. A market survey was conducted to identify the application areas for this heat recovery system. A cost/benefit analysis showed a payback period of less than one and a half years.

Displacement measurement system for linear array detector

International Nuclear Information System (INIS)

Zhang Pengchong; Chen Ziyu; Shen Ji

2011-01-01

It presents a set of linear displacement measurement system based on encoder. The system includes displacement encoders, optical lens and read out circuit. Displacement read out unit includes linear CCD and its drive circuit, two amplifier circuits, second order Butterworth low-pass filter and the binarization circuit. The coding way is introduced, and various parts of the experimental signal waveforms are given, and finally a linear experimental test results are given. The experimental results are satisfactory. (authors)
Stability Evaluation of Buildings in Urban Area Using Persistent Scatterer Interfometry -Focused on Thermal Expansion Effect

Science.gov (United States)

Choi, J. H.; Kim, S. W.; Won, J. S.

2017-12-01

The objective of this study is monitoring and evaluating the stability of buildings in Seoul, Korea. This study includes both algorithm development and application to a case study. The development focuses on improving the PSI approach for discriminating various geophysical phase components and separating them from the target displacement phase. A thermal expansion is one of the key components that make it difficult for precise displacement measurement. The core idea is to optimize the thermal expansion factor using air temperature data and to model the corresponding phase by fitting the residual phase. We used TerraSAR-X SAR data acquired over two years from 2011 to 2013 in Seoul, Korea. The temperature fluctuation according to seasons is considerably high in Seoul, Korea. Other problem is the highly-developed skyscrapers in Seoul, which seriously contribute to DEM errors. To avoid a high computational burden and unstable solution of the nonlinear equation due to unknown parameters (a thermal expansion parameter as well as two conventional parameters: linear velocity and DEM errors), we separate a phase model into two main steps as follows. First, multi-baseline pairs with very short time interval in which deformation components and thermal expansion can be negligible were used to estimate DEM errors first. Second, single-baseline pairs were used to estimate two remaining parameters, linear deformation rate and thermal expansion. The thermal expansion of buildings closely correlate with the seasonal temperature fluctuation. Figure 1 shows deformation patterns of two selected buildings in Seoul. In the figures of left column (Figure 1), it is difficult to observe the true ground subsidence due to a large cyclic pattern caused by thermal dilation of the buildings. The thermal dilation often mis-leads the results into wrong conclusions. After the correction by the proposed method, true ground subsidence was able to be precisely measured as in the bottom right figure
Experimental Study of Enhancing Oil Recovery with Weak Base Alkaline/Surfactant/Polymer

Directory of Open Access Journals (Sweden)

Dandan Yin

2017-01-01

Full Text Available Na2CO3 was used together with surfactant and polymer to form the Alkaline/Surfactant/Polymer (ASP flooding system. Interfacial tension (IFT and emulsification of Dagang oil and chemical solutions were studied in the paper. The experiment results show that the ASP system can form super-low interfacial tension with crude oil and emulsified phase. The stability of the emulsion is enhanced by the Na2CO3, surfactant, and the soap generated at oil/water contact. Six core flooding experiments are conducted in order to investigate the influence of Na2CO3 concentration on oil recovery. The results show the maximum oil recovery can be obtained with 0.3 wt% surfactant, 0.6 wt% Na2CO3, and 2000 mg/L polymer. In a heterogeneous reservoir, the ASP flooding could not enhance the oil recovery by reducing IFT until it reaches the critical viscosity, which indicates expanding the sweep volume is the premise for reducing IFT to enhance oil recovery. Reducing or removing the alkali from ASP system to achieve high viscosity will reduce oil recovery because of the declination of oil displacement efficiency. Weak base ASP alkali can ensure that the whole system with sufficient viscosity can start the medium and low permeability layers and enhance oil recovery even if the IFT only reaches 10−2 mN/m.
Water-displacement plethysmography: a technique for the simultaneous thermal manipulation and measurement of whole-hand and whole-foot blood flows

International Nuclear Information System (INIS)

Caldwell, Joanne N; Taylor, Nigel A S

2014-01-01

The purpose of this project was to design, construct and validate water-displacement plethysmographs for the forearm, hand and foot that could clamp segmental skin temperature whilst simultaneously measuring cutaneous blood flow. Two experiments were performed. In the first, the forearm plethysmograph was validated against a mercury-in-silastic plethysmograph under thermoneutral conditions, with and without forearm heating. Cutaneous vascular conductance was elevated almost three-fold by this treatment, however, there were no significant differences between the two forms of plethysmography in either state (P > 0.05). In study two, hand and foot blood flows were measured under clamped thermoneutral conditions, but with three local skin temperature treatments (5, 25, 40 °C). The hand had significantly higher blood flows than the foot at both 25 °C (4.07 versus 2.20 mL.100 mL − 1 .min − 1 ; P < 0.05) and 40 °C (8.20 versus 4.47 mL.100 mL − 1 .min − 1 ; P < 0.05). The foot was maximally constricted during the two lower temperatures, yet the cutaneous thermal sensitivity of the hand was almost two-fold greater (P < 0.05). This evidence supports the significant role played by these appendages in heat loss and conservation, and these plethysmographs will now be used to map cutaneous vascular responses (forearm, hand, calf, foot) across combinations of core and local skin temperatures. (paper)
Experimental and modeling study of forest fire effect on soil thermal conductivity

Science.gov (United States)

Kathleen M. Smits; Elizabeth Kirby; William J. Massman; Scott Baggett

2016-01-01

An understanding of soil thermal conductivity after a wildfire or controlled burn is important to land management and post-fire recovery efforts. Although soil thermal conductivity has been well studied for non-fire heated soils, comprehensive data that evaluate the long-term effect of extreme heating from a fire on the soil thermal conductivity are limited....
Job Displacement and First Birth Over the Business Cycle.

Science.gov (United States)

Hofmann, Barbara; Kreyenfeld, Michaela; Uhlendorff, Arne

2017-06-01

In this article, we investigate the impact of job displacement on women's first-birth rates as well as the variation in this effect over the business cycle. We use mass layoffs to estimate the causal effects of involuntary job loss on fertility in the short and medium term, up to five years after displacement. Our analysis is based on rich administrative data from Germany, with an observation period spanning more than 20 years. We apply inverse probability weighting (IPW) to flexibly control for the observed differences between women who were and were not displaced. To account for the differences in the composition of the women who were displaced in a downturn and the women who were displaced in an upswing, we use a double weighting estimator. Results show that the extent to which job displacement has adverse effects on fertility depends on the business cycle. The first-birth rates were much lower for women who were displaced in an economic downturn than for those who lost a job in an economic upturn. This result cannot be explained by changes in the observed characteristics of the displaced women over the business cycle.
The displacement of oil polymer slug considering of adsorption effects; Deslocamento de oleo por banco de polimero considerando os efeitos de adsorcao

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, Priscila M. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Pires, Adolfo P. [Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacazes, RJ (Brazil)

2008-07-01

Among different Enhanced Oil Recovery methods, the injection of chemical solutions plays an important role in mature fields additional recovery. The continuous injection of this kind of fluid would be very expensive, so, the injection of chemical slugs is an attractive alternative to improve the recovery of mature oil fields. Analytical models for 1-D displacement of oil by water with chemical compounds have been developed since the 1960's. This paper presents the 1-D analytical solution of the injection of a chemical slug followed by water drive into an oil reservoir. A flow potential associated with the conservation of water phase is introduced and used as a new independent variable instead of time. This technique permits splitting the system of equations into a thermodynamic system and one transport equation. Another important application of these solutions is the prediction of chemical flooding regardless of the transport properties (relative permeabilities and viscosities). (author)
Fuel retention and recovery in natural and MGI disruptions on KSTAR

International Nuclear Information System (INIS)

Yu, Y.W.; Hong, S.H.; Yoon, S.W.; Kim, K.P.; Kim, W.C.; Seo, D.C.

2013-01-01

Fuel retention and recovery are studied during natural and Massive Gas Injection (MGI) induced disruptions in KSTAR with full graphite wall. The amount of released particles in natural disruptions in 15 s after the discharge is ∼5–10 times higher than that of non-disruption shots, but the difference is only ∼ 2 MGI induced disruptions depends on magnetic field (B t ) and MGI amount. The MGI disruption under a low B t and a medium MGI amount shows shorter thermal quench (TQ) and current quench (CQ), thereby higher fuel recovery. High B t plasma requires higher MGI amount for both disruption mitigation and fuel recovery. A high recovery of 4.2 × 10 22 D (∼0.78 monolayers) is obtained by MGI disruption in KSTAR 2011
Stability of Miscible Displacements Across Stratified Porous Media

Energy Technology Data Exchange (ETDEWEB)

Shariati, Maryam; Yortsos, Yanis C.

2000-09-11

This report studied macro-scale heterogeneity effects. Reflecting on their importance, current simulation practices of flow and displacement in porous media were invariably based on heterogeneous permeability fields. Here, it was focused on a specific aspect of such problems, namely the stability of miscible displacements in stratified porous media, where the displacement is perpendicular to the direction of stratification.
Solar-generated steam for oil recovery: Reservoir simulation, economic analysis, and life cycle assessment

International Nuclear Information System (INIS)

Sandler, Joel; Fowler, Garrett; Cheng, Kris; Kovscek, Anthony R.

2014-01-01

Highlights: • Integrated assessment of solar thermal enhanced oil recovery (TEOR). • Analyses of reservoir performance, economics, and life cycle factors. • High solar fraction scenarios show economic viability for TEOR. • Continuous variable-rate steam injection meets the benchmarks set by conventional steam flood. - Abstract: The viability of solar thermal steam generation for thermal enhanced oil recovery (TEOR) in heavy-oil sands was evaluated using San Joaquin Valley, CA data. The effectiveness of solar TEOR was quantified through reservoir simulation, economic analysis, and life-cycle assessment. Reservoir simulations with continuous but variable rate steam injection were compared with a base-case Tulare Sand steamflood project. For equivalent average injection rates, comparable breakthrough times and recovery factors of 65% of the original oil in place were predicted, in agreement with simulations in the literature. Daily cyclic fluctuations in steam injection rate do not greatly impact recovery. Oil production rates do, however, show seasonal variation. Economic viability was established using historical prices and injection/production volumes from the Kern River oil field. For comparison, this model assumes that present day steam generation technologies were implemented at TEOR startup in 1980. All natural gas cogeneration and 100% solar fraction scenarios had the largest and nearly equal net present values (NPV) of $12.54 B and $12.55 B, respectively. Solar fraction refers to the steam provided by solar steam generation. Given its large capital cost, the 100% solar case shows the greatest sensitivity to discount rate and no sensitivity to natural gas price. Because there are very little emissions associated with day-to-day operations from the solar thermal system, life-cycle emissions are significantly lower than conventional systems even when the embodied energy of the structure is considered. We estimate that less than 1 g of CO 2 /MJ of refined
Thermal Energy Recovery through Optimal Salt concentration in a Parabolic Trough Systems

Directory of Open Access Journals (Sweden)

Ramsurn Rikesh

2018-01-01

Full Text Available Making a PVT system hybrid is to support the use of thermal and electrical energy simultaneously or independently, to control the thermal effect to improve electrical efficiency or vice-versa. This project makes use of the Parabolic Trough design with emphasis on making the system to be sustainable and also increasing the thermal efficiency of the system. Polystyrene and acrylic foam is utilized to maximize the heat retention capability of the system. To power, the pump that moves the heat transfer fluid (tested with salt water proportions within the copper tube, a set of solar PV panel is to support its power demand making it sustainable. The closed loop setup designed achieved an improved thermal efficiency level of 66.2%, which contributes to having a reliable heat energy source for applications such as hot showers. The novel setup design also makes use of PV cells to support other energy demands through power electronic control designs. Using a similar heat dissipation technique, a novel setup has been designed to improve the voltage supply by making use of liquid cooling and translucent glass PV panels. Cooling the PV panel restored up to 11.7% of its rated voltage supply. This is achieved by keeping the PV panels within its best thermal operating conditions using an energy efficient electronically controlled cooling system.
Atomic displacements in bcc dilute alloys

Indian Academy of Sciences (India)

We present here a systematic investigation of the atomic displacements in bcc transition metal (TM) dilute alloys. We have calculated the atomic displacements in bcc (V, Cr, Fe, Nb, Mo, Ta and W) transition metals (TMs) due to 3d, 4d and 5d TMs at the substitutional site using the Kanzaki lattice static method. Wills and ...
Buckling of thermally fluctuating spherical shells: Parameter renormalization and thermally activated barrier crossing

Science.gov (United States)

Baumgarten, Lorenz; Kierfeld, Jan

2018-05-01

We study the influence of thermal fluctuations on the buckling behavior of thin elastic capsules with spherical rest shape. Above a critical uniform pressure, an elastic capsule becomes mechanically unstable and spontaneously buckles into a shape with an axisymmetric dimple. Thermal fluctuations affect the buckling instability by two mechanisms. On the one hand, thermal fluctuations can renormalize the capsule's elastic properties and its pressure because of anharmonic couplings between normal displacement modes of different wavelengths. This effectively lowers its critical buckling pressure [Košmrlj and Nelson, Phys. Rev. X 7, 011002 (2017), 10.1103/PhysRevX.7.011002]. On the other hand, buckled shapes are energetically favorable already at pressures below the classical buckling pressure. At these pressures, however, buckling requires to overcome an energy barrier, which only vanishes at the critical buckling pressure. In the presence of thermal fluctuations, the capsule can spontaneously overcome an energy barrier of the order of the thermal energy by thermal activation already at pressures below the critical buckling pressure. We revisit parameter renormalization by thermal fluctuations and formulate a buckling criterion based on scale-dependent renormalized parameters to obtain a temperature-dependent critical buckling pressure. Then we quantify the pressure-dependent energy barrier for buckling below the critical buckling pressure using numerical energy minimization and analytical arguments. This allows us to obtain the temperature-dependent critical pressure for buckling by thermal activation over this energy barrier. Remarkably, both parameter renormalization and thermal activation lead to the same parameter dependence of the critical buckling pressure on temperature, capsule radius and thickness, and Young's modulus. Finally, we study the combined effect of parameter renormalization and thermal activation by using renormalized parameters for the energy
Internal Displacement, the Guiding Principles on Internal Displacement, the Principles Normative Status, and the Need for their Effective Domestic Implementation in Colombia.

Directory of Open Access Journals (Sweden)

Robert K. Goldman

2010-05-01

Full Text Available The paper briefly examines the phenomenon of internal displacement world-wide and the genesis of the United Nation’s mandate to deal with this problem. It examines key conclusions of a UN sponsored study which found that existing international law contained signifi cant gaps and grey areas in terms of meeting the needs of internally displaced persons. It also examines the origins and the content of the Guiding Principles on Internal Displacement and the normative status of these Principles. It suggests that, while not binding as such on states, the Guiding Principles have nonetheless become the most authoritative expression of minimum international standards applicable to the internally displaced and that based on state practice many, if not all, of these principles may eventually become part of customary international law. The paper also discusses the need for effective domestic implementation of the Guiding Principles, and examines how governmental authorities, the Constitutional Court and civil society organizations in Colombia, as well as inter-governmental bodies, have responded to the crisis of internal displacement in the country. While noting the adequacy of Colombia’s legislative framework on internal displacement, the paper concludes that the State has not taken the measures required to prevent future displacement or to effectively meet the protection and assistance needs of its displaced citizens.
The Effect of Basepair Mismatch on DNA Strand Displacement

OpenAIRE

Broadwater, D.?W.?Bo; Kim, Harold?D.

2016-01-01

DNA strand displacement is a key reaction in DNA homologous recombination and DNA mismatch repair and is also heavily utilized in DNA-based computation and locomotion. Despite its ubiquity in science and engineering, sequence-dependent effects of displacement kinetics have not been extensively characterized. Here, we measured toehold-mediated strand displacement kinetics using single-molecule fluorescence in the presence of a single base pair mismatch. The apparent displacement rate varied si...
The role of environmental degradation in population displacement.

Science.gov (United States)

Lonergan, S

1998-01-01

This article answers a series of questions about the role of environmental degradation in population displacement, refugee movement, and migration. The environment tends not to be included in the reasons for migration. Roger's indicators of migration potential include population growth, economic restructuring, increased economic disparities, and increased refugee flows. Myers (1993) estimated that international displacement and internal displacement may amount to about 25 million and may rise to 150 million by 2050. The role of the environment in displacement must be examined in the broader political and cultural context. Definitions of environmental refugees are ambiguous and inconsistent, and research has not answered why people continue to move to Mexico City and Chongqing, China, which both have very high levels of pollution. El-Hinnawi (1985) defined 3 groups of environmental refugees: those displaced due to natural disasters; those displaced due to permanent habitat changes; and those displaced who migrated from areas that cannot support their basic needs and who desire an improved quality of life. Lonergan (1994) identified environmental stresses as natural disasters, cumulative or slow-onset changes, accidental disruptions or industrial accidents, development projects, and conflict and warfare. These 5 causes must be treated separately and not lumped together as environmental degradation. Shoreline erosion, coastal flooding, and agricultural disruption associated with climate change may increase migration. Global measures must address world poverty and promote sustainable development.
Modelling of waste heat recovery for combined heat and power applications

International Nuclear Information System (INIS)

Descombes, Georges; Boudigues, Serge

2009-01-01

The current environmental context dictates to reduce the pollutant emissions by improving thermal efficiency of the energy production units. The authors present some studies of cogeneration applications using gas turbines and thermal engines. The on-going research concerns a detailed study of thermodynamic modelling cycles with energy recovery. These combined cycles with gas turbine and ICE can generate a potential increase of about 10% of the energy efficiency. They will generate a technological complexity and the over-charge must be estimated. At last, the authors insist on the necessary synergy between gas turbines and thermal engines.
Transport of runaway and thermal electrons due to magnetic microturbulence

International Nuclear Information System (INIS)

Mynick, H.E.; Strachan, J.D.

1981-01-01

The ratio of the runaway electron confinement to thermal electron energy confinement is derived for tokamaks where both processes are determined by free streaming along stochastic magnetic field lines. The runaway electron confinement is enhanced at high runaway electron energies due to phase averaging over the magnetic perturbations when the runaway electron drift surfaces are displaced from the magnetic surfaces. Comparison with experimental data from LT-3, Ormak, PLT, ST, and TM-3 indicates that magnetic stochasticity may explain the relative transport rates of runaways and thermal electron energy
Effect of Freezing, Thermal Pasteurization, and Hydrostatic Pressure on Fractionation and Folate Recovery in Egg Yolk.

Science.gov (United States)

Naderi, Nassim; Pouliot, Yves; House, James D; Doyen, Alain

2017-09-06

In this study, the impact of pasteurization and freezing of raw material, as performed at a commercial scale, on egg yolk fractionation and folate recovery was assessed. Freezing induced denaturation of the lipoproteins in egg yolk, which prevented further fractionation of the yolk. Thermal pasteurization of egg yolk at 61.1 °C for 3.5 min as well as high hydrostatic pressure (HHP) treatment (400 MPa for 5 min) did not change (p < 0.05) the composition of egg yolk or yolk fractions after their recovery by centrifugation. Expressed as dry matter, folate in pasteurized yolk was measured to be 599 μg/100 g, while its concentration reached 1969.7 μg/100 g for pasteurized granule and 1902.5 μg/100 g for HHP-treated granule. Folate was not detected in plasma, emphasizing the complete separation of yolk folate into granule. Further, we studied the effect of HHP on different dilutions of egg yolk, which were then fractionated. Egg yolk was diluted with water at different concentrations (0.1, 1.0, 10, 25, and 50%), HHP-treated at 400 MPa for 5 min, and centrifuged. Characterization of the compositions of the separated granule and plasma followed. Folate was stable under the HHP conditions used. However, HHP caused separation of folate from the yolk structure into water-soluble plasma. After HHP processing, the amount of folate detected in the plasma fraction was significantly (p < 0.05) higher (1434.9 μg/100 g) in the 25% diluted samples but was significantly (p < 0.05) lower in HHP-treated granule samples. Native sodium dodecyl sulfate-polyacrylamide gel electrophoresis results showed that phosvitin, α-livetin, and apovitellenin VIa were the proteins most resistant to HHP. This study confirms that dilution of egg yolk before HHP treatment can significantly (p < 0.05) change the composition of granule and plasma fractions after centrifugal fractionation of egg yolk.
Displacement laser interferometry with sub-nanometer uncertainty

NARCIS (Netherlands)

Cosijns, S.J.A.G.

2004-01-01

Development in industry is asking for improved resolution and higher accuracy in mechanical measurement. Together with miniaturization the demand for sub nanometer uncertainty on dimensional metrology is increasing rapidly. Displacement laser interferometers are used widely as precision displacement

Efficiency of a variable displacement open circuit floating cup pump

NARCIS (Netherlands)

Vael, G.E.M.; Achten, P.A.J.; Brink, van den T.L.

2009-01-01

The Floating Cup Displacement principle is a relatively new axial piston displacement principle for hydrostatic pumps, motors and transformers. Since its origin in 2001, it has been mainly applied in fixed displacement pump prototypes. At the SICFP’05, a design for a variable displacement open
Epitaxial growth by monolayer restricted galvanic displacement

Directory of Open Access Journals (Sweden)

Vasilić Rastko

2012-01-01

Full Text Available The development of a new method for epitaxial growth of metals in solution by galvanic displacement of layers pre-deposited by underpotential deposition (UPD was discussed and experimentally illustrated throughout the lecture. Cyclic voltammetry (CV and scanning tunneling microscopy (STM are employed to carry out and monitor a “quasi-perfect”, two-dimensional growth of Ag on Au(111, Cu on Ag(111, and Cu on Au(111 by repetitive galvanic displacement of underpotentially deposited monolayers. A comparative study emphasizes the displacement stoichiometry as an efficient tool for thickness control during the deposition process and as a key parameter that affects the deposit morphology. The excellent quality of layers deposited by monolayer-restricted galvanic displacement is manifested by a steady UPD voltammetry and ascertained by a flat and uniform surface morphology maintained during the entire growth process.
Silicon carbide layer structure recovery after ion implantation

International Nuclear Information System (INIS)

Violin, Eh.E.; Demakov, K.D.; Kal'nin, A.A.; Nojbert, F.; Potapov, E.N.; Tairov, Yu.M.

1984-01-01

The process of recovery of polytype structure of SiC surface layers in the course of thermal annealing (TA) and laser annealing (LA) upon boron and aluminium implantation is studied. The 6H polytype silicon carbide C face (0001) has been exposed to ion radiation. The ion energies ranged from 80 to 100 keV, doses varied from 5x10 14 to 5x10 16 cm -2 . TA was performed in the 800-2000 K temperature range. It is shown that the recovery of the structure of silicon carbide layers after ion implantation takes place in several stages. Considerable effect on the structure of the annealed layers is exerted by the implantation dose and the type of implanted impurity. The recovery of polytype structure is possible only under the effect of laser pulses with duration not less than the time for the ordering of the polytype in question
On the Recovery Stress of a Ni50.3Ti29.7Hf20 High Temperature Shape Memory Alloy

Science.gov (United States)

Benafan, O.; Noebe, R. D.; Padula, S. A., II; Bigelow, G. S.; Gaydosh, D. J.; Garg, A.; Halsmer, T. J.

2015-01-01

Recovery stress in shape memory alloys (SMAs), also known as blocking stress, is an important property generally obtained during heating under a dimensional constraint as the material undergoes the martensitic phase transformation. This property has been instinctively utilized in most SMA shape-setting procedures, and has been used in numerous applications such as fastening and joining, rock splitting, safety release mechanisms, reinforced composites, medical devices, and many other applications. The stress generation is also relevant to actuator applications where jamming loads (e.g., in case the actuator gets stuck and is impeded from moving) need to be determined for proper hardware sizing. Recovery stresses in many SMA systems have been shown to reach stresses in the order of 800 MPa, achieved via thermo-mechanical training such as pre-straining, heat treatments or other factors. With the advent of high strength, high temperature SMAs, recovery stress data has been rarely probed, and there is no information pertinent to the magnitudes of these stresses. Thus, the purpose of this work is to investigate the recovery stress capability of a precipitation strengthened, Ni50.3Ti29.7Hf20 (at.) high temperature SMA in uniaxial tension and compression. This material has been shown to exhibit outstanding strength and stability during constant-stress, thermal cycling, but no data exists on constant-strain thermal cycling. Several training routines were implemented as part of this work including isothermal pre-straining, isobaric thermal cycling, and isothermal cyclic training routines. Regardless of the training method used, the recovery stress was characterized using constant-strain (strain-controlled condition) thermal cycling between the upper and lower cycle temperatures. Preliminary results indicate recovery stresses in excess of 1.5 GPa were obtained after a specific training routine. This stress magnitude is significantly higher than conventional NiTi stress
Thermal recovery simulation at the pore-network level; Simulacao de recuperacao termica em escala microscopica

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Claudio L.N.; Almeida, Murilo P.; Andrade Junior, Jose S. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil); Herrmann, Hans J. [Eidgenossische Technische Hochschule Zurich (ETHZ), Zurich (Switzerland)

2008-07-01

We have investigated the effect of temperature in penetration of an inviscid fluid into a porous media saturated with a very high viscous fluid. Gradient of temperature is applied across the medium. The viscosity of the defending fluid is considered as an exponential-like function with temperature. This scheme represents a small fraction of a heavy oil reservoir where steam injection is applied. The results show that the recovery of the viscous fluid is a hyperbolic tangent function with the difference of temperature, where it has a maximum recovery for high gradient. Our results show, also, that the recovery efficiency can increase substantially with the gradient of temperature. (author)
Acoustic wave emission for enhanced oil recovery (WAVE.O.R.)

International Nuclear Information System (INIS)

Reichmann, S.; Amro, M.; Giese, R.; Jaksch, K.; Krauss, F.; Krueger, K.; Jurczyk, A.

2016-09-01

In the project WAVE.O.R the potential of acoustic waves to enhance oil recovery was reviewed. The project focused on laboratory experiments of the oil displacement in sandstone cores under acoustic stimulation. Additionally, the Seismic Prediction While Drilling (SPWD) borehole device prototype was set up for a feasibility field test. The laboratory experiments showed that, depending on the stimulation frequency, acoustic stimulation allows for an enhanced oil recovery. For single frequency stimulation a mean increase of 3 % pore volumes was observed at distinguished frequencies. A cyclic stimulation, where two of these frequencies were combined, an increase of 5% pore volume was observed. The SPWD borehole device was tested and adjusted during feasibility tests in the GFZ underground laboratory in the research and education mine ''Reiche Zeche'' of the TU Bergakademie Freiberg and in the GFZ KTB-Deep Laboratory in Windischeschenbach. The first successful test of the device under realistic conditions was performed at the test site ''Piana di Toppo'' of the OGS Trieste, Italy.
A thermal-driven silicon micro xy-stage integrated with piezoresistive sensors for nano-positioning

International Nuclear Information System (INIS)

Choi, Young-Soo; Zhang, Yan; Lee, Dong-Weon

2012-01-01

This paper describes a novel micro xy-stage, driven by double-hot arm horizontal thermal micro-actuators integrated with a piezoresistive sensor (PS) for low-voltage operation and precise control. This micro xy-stage structure is linked with chevron beams and optimized to amplify the displacement generated by the micro-actuators that provide a pull force to the movable platform. The PS employed for in situ displacement detection and feedback control is fabricated at the base of a cold arm, which minimizes the influence of temperature change induced by electro-thermal heating. The micro xy-stage structure is defined through the use of a simple micromachining process, released by backside wet etching with a special tool. For an input power of approximately 44 mW, each chevron actuator provides about 16 µm and the total displacement of the platform is close to 32 µm. The sensitivity of the PS is better than 1 mV µm −1 , obtained from the amplified voltage output of the Wheatstone bridge circuit. The potential applications of the proposed micro xy-stage lie in micro- or nano-manipulation, as well as the positioning of ultra-small objects in nanotechnology. (paper)
Application of electronic speckle-pattern interferometry to measure in-plane thermal displacement in flip-chip packages

International Nuclear Information System (INIS)

Lee, Baik-Woo; Jang, Woosoon; Kim, Dong-Won; Jeong, Jeung-hyun; Nah, Jae-Woong; Paik, Kyung-Wook; Kwon, Dongil

2004-01-01

Electronic speckle-pattern interferometry (ESPI) was applied for noncontact, real-time evaluation of thermal deformation in a flip-chip package. The spatial resolution of ESPI was increased to submicron scale by magnifying the areas studied in order to measure the deformation of such small-scale components as the solder in the flip-chip package. Thermal deformation in the horizontal and vertical directions around the solder joints was measured as two-dimensional mappings during heating from 25 to 125 deg. C. ESPI was successful in obtaining information on the complicated deformation field around the solder joints. Furthermore, the shear strain could also be calculated using the measured thermal deformation around each solder joint. The applicability of ESPI to flip-chip packages was verified by comparing the ESPI results with those of finite-element analysis (FEA)
Study of thermal energy storage using fluidized bed heat exchangers

Science.gov (United States)

Weast, T. E.; Shannon, L. J.; Ananth, K. P.

1980-01-01

The technical and economic feasibility of fluid bed heat exchangers (FBHX) for thermal energy storage (TES) in waste heat recovery applications is assessed by analysis of two selected conceptual systems, the rotary cement kiln and the electric arc furnace. It is shown that the inclusion of TES in the energy recovery system requires that the difference in off-peak and on-peak energy rates be large enough so that the value of the recovered energy exceeds the value of the stored energy by a wide enough margin to offset parasitic power and thermal losses. Escalation of on-peak energy rates due to fuel shortages could make the FBHX/TES applications economically attractive in the future.
Fiber-optic couplers as displacement sensors

Science.gov (United States)

Baruch, Martin C.; Gerdt, David W.; Adkins, Charles M.

2003-04-01

We introduce the novel concept of using a fiber-optic coupler as a versatile displacement sensor. Comparatively long fiber-optic couplers, with a coupling region of approximately 10 mm, are manufactured using standard communication SM fiber and placed in a looped-back configuration. The result is a displacement sensor, which is robust and highly sensitive over a wide dynamic range. This displacement sensor resolves 1-2 μm over distances of 1-1.5 mm and is characterized by the essential absence of a 'spring constant' plaguing other strain gauge-type sensors. Consequently, it is possible to couple to extremely weak vibrations, such as the skin displacement affected by arterial heart beat pulsations. Used as a wrist-worn heartbeat monitor, the fidelity of the arterial pulse signal has been shown to be so high that it is possible to not only determine heartbeat and breathing rates, but to implement a new single-point blood pressure measurement scheme which does not squeeze the arm. In an application as a floor vibration sensor for the non-intrusive monitoring of independently living elderly, the sensor has been shown to resolve the distinct vibration spectra of different persons and different events.
Topology synthesis of large-displacement compliant mechanisms

DEFF Research Database (Denmark)

Pedersen, Claus B. Wittendorf; Buhl, Thomas; Sigmund, Ole

2001-01-01

This paper describes the use of topology optimization as a synthesis tool for the design of large-displacement compliant mechanisms. An objective function for the synthesis of large-displacement mechanisms is proposed together with a formulation for synthesis of path-generating compliant mechanisms...
Prolonged displacement may compromise resilience in Eritrean ...

African Journals Online (AJOL)

Objective: to assess the impact of prolonged displacement on the resilience of Eritrean mothers. Methods: an adapted SOC scale (short form) was administered. Complementary qualitative data were gathered from study participants' spontaneous reactions to and commentaries on the SOC scale. Results: Displaced ...
Embrittlement recovery due to annealing of reactor pressure vessel steels

International Nuclear Information System (INIS)

Eason, E.D.; Wright, J.E.; Nelson, E.E.; Odette, G.R.; Mader, E.V.

1998-01-01

The irradiation embrittlement of nuclear reactor pressure vessels (RPV) can be reduced by thermal annealing at temperatures higher than the normal operating conditions. The objective of this work was to analyze the pertinent data and develop quantitative models for estimating the recovery in 41 J (30 ft-lb) Charpy transition temperature (TT) and Charpy upper shelf energy (USE) due to annealing. An analysis data base was developed, reviewed for completeness and accuracy, and documented as part of this work. Models were developed based on a combination of statistical techniques, including pattern recognition and transformation analysis, and the current understanding of the mechanisms governing embrittlement and recovery. The quality of models fitted in this project was evaluated by considering both the Charpy annealing data used for fitting and a surrogate hardness data base. This work demonstrates that microhardness recovery is a good surrogate for shift recovery and that there is a high level of consistency between the observed annealing trends and fundamental models of embrittlement and recovery processes. (orig.)
Soil Thermal Balance Analysis for a Ground Source Heat Pump System in a Hot-Summer and Cold-Winter Region

Directory of Open Access Journals (Sweden)

Zhongchao Zhao

2018-05-01

Full Text Available As a renewable and high energy efficiency technology providing air conditioning and domestic hot water, the ground source heat pump system (GSHPS has been extensively used worldwide in recent years. Compared with conventional systems, GSHPSs with heat recovery reject less heat into the soil and extract more heat from it, which can help reduce soil thermal imbalance in hot-summer and cold-winter regions. In this paper, conventional GSHPS, and GSHPS with different heat recovery ratios, in a typical city were compared based on thermal imbalance ratios, average soil temperatures and soil temperature increases. The transient system simulation software was used to simulate the operation performance of GSHPS. The thermal imbalance ratio and soil temperature decreased with increasing heat recovery ratio. After 20 years of operation, the soil thermal imbalance ratios of the GSHPS were 29.2%, 21.1%, 16%, and 5.2%, and the soil temperature rises were 8.78 °C, 5.25 °C, 3.44 °C, and 0.34 °C, while the heat recovery ratios were 0, 18%, 30% and 53%, respectively. Consequently, a GSHPS with heat recovery is a potentially efficient and economical approach for buildings in hot-summer and cold-winter regions.
Job displacement and stress-related health outcomes

DEFF Research Database (Denmark)

Browning, Martin; Danø, Anne Møller; Heinesen, Eskil

2006-01-01

We investigate whether job loss as the result of displacement causes hospitalization for stress-related diseases which are widely thought to be associated with unemployment. In doing this, we use much better data than any previous investigators. Our data are a random 10% sample of the male...... group of displaced workers if they had not in fact been displaced. Our results indicate unequivocally that being displaced in Denmark does not cause hospitalization for stress-related disease. An analysis of the power of our test suggests that even though we are looking for a relatively rare outcome...... population of Denmark for the years 1981-1999 with full records on demographics, health and work status for each person, and with a link from every working person to a plant. We use the method of matching on observables to estimate the counter-factual of what would have happened to the health of a particular...
On virtual displacement and virtual work in Lagrangian dynamics

International Nuclear Information System (INIS)

Ray, Subhankar; Shamanna, J

2006-01-01

The confusion and ambiguity encountered by students in understanding virtual displacement and virtual work is discussed in this paper. A definition of virtual displacement is presented that allows one to express them explicitly for holonomic (velocity independent), non-holonomic (velocity dependent), scleronomous (time independent) and rheonomous (time dependent) constraints. It is observed that for holonomic, scleronomous constraints, the virtual displacements are the displacements allowed by the constraints. However, this is not so for a general class of constraints. For simple physical systems, it is shown that the work done by the constraint forces on virtual displacements is zero. This motivates Lagrange's extension of d'Alembert's principle to a system of particles in constrained motion. However, a similar zero work principle does not hold for the allowed displacements. It is also demonstrated that d'Alembert's principle of zero virtual work is necessary for the solvability of a constrained mechanical problem. We identify this special class of constraints, physically realized and solvable, as the ideal constraints. The concept of virtual displacement and the principle of zero virtual work by constraint forces are central to both Lagrange's method of undetermined multipliers and Lagrange's equations in generalized coordinates
2014 and beyond: implications for displacement

Directory of Open Access Journals (Sweden)

Aidan O’Leary

2014-05-01

Full Text Available 2014 marks a watershed for Afghanistan, with the withdrawal of the International Security Assistance Force after twelve years, and the very real risks this withdrawal poses to the capacity of the Afghan state to meet the many internal and external challenges faced by the country. These challenges have significant implications for displaced and returning Afghans and for the potential for displacement in the future.
A review of waste heat recovery technologies for maritime applications

International Nuclear Information System (INIS)

Singh, Dig Vijay; Pedersen, Eilif

2016-01-01

Highlights: • Major waste heat sources available on ships have been reviewed. • A review of suitable waste heat recovery systems was conducted for marine vessels. • Technologies have been compared for their potential and suitability for marine use. • Kalina cycle offers the highest potential for marine waste heat recovery. • Turbo compound system most suitable for recovering diesel exhaust pressure energy. - Abstract: A waste heat recovery system produces power by utilizing the heat energy lost to the surroundings from thermal processes, at no additional fuel input. For marine vessels, about 50 percent of the total fuel energy supplied to diesel power-plant aboard is lost to the surroundings. While the total amount of wasted energy is considerable, the quality of this energy is quite low due to its low temperature and has limited potential for power production. Effective waste heat recovery systems use the available low temperature waste heat to produce mechanical/electrical power with high efficiency value. In this study a review of different waste heat recovery systems has been conducted, to lay out the potential recovery efficiencies and suitability for marine applications. This work helps in identifying the most suitable heat recovery technologies for maritime use depending on the properties of shipboard waste heat and achievable recovery efficiencies, whilst discussing the features of each type of system.
Solar thermal barometer

International Nuclear Information System (INIS)

Anon.

2010-01-01

In 2008, the European solar thermal market put on a strong spurt only to mark time in 2009 with about 4.2 million m 2 installed, which is 450000 m 2 less year-on-year. The main reasons of the decrease is the financial crisis and the low oil price, other reasons more specific to the country exist, for instance the property crisis has dragged the Spanish market down. In 2009, the solar thermal collector surface area in service in the European Union is of the magnitude of 32.6 million m 2 , equivalent to a capacity of 22.8 GWTh. The solar thermal sector is one of the renewable sectors that creates the highest number of jobs and wealth, partly because the vast majority of the system components sold in Europe are produced in Europe and partly because the sale, installation fitting and maintenance are labour-intensive. In 2009, there were 50000 direct or indirect jobs in the European solar thermal sector. The main European actors in this sector are GREENoneTEC, Bosch-Thermotechnik, Viessmann, Vaillant and Solvis. No clear recovery is expected before 2011. (A.C.)
ICP-AES determination of rare earth elements in coal fly ash samples of thermal power stations: assessment of possible recovery and environmental impact of rare earth elements

International Nuclear Information System (INIS)

Premadas, A.; Mary, Thomas Anitha; Chakrapani, G.

2013-01-01

Accurate determination of rare earth elements (REEs) in ashes of thermal power plants is important in the current scenario due to its economic value, and the pollution caused if they are released in to the environment. Their toxicity to living organisms now gaining importance in international community, and some investigation shows it causes retardation in plant growth. In coal based thermal stations huge quantity of coal used annually as a fuel and lakhs of tones of waste is generated in the form of ashes. Therefore studies were carried out on three aspects - fairly rapid and accurate ICP-AES determination REEs in coal fly ash samples using addition technique, a preliminary acid leaching studies on coal received from three different fired thermal power stations using hydrochloric acid at pH 1 and 2, and quantify the REEs leached, and economic recovery of REEs using di-(2-ethylhexyl) phosphoric acid solvent extraction process or precipitation hydroxides using dilute ammonia solution. The standard addition method of REEs determination using rate and reproducible values, besides the analysis is fast compared to the ion exchange separation of REEs followed by the ICP-AES determination. (author)

Oil Recovery Increases by Low-Salinity Flooding: Minnelusa and Green River Formations

Energy Technology Data Exchange (ETDEWEB)

Eric P. Robertson

2010-09-01

Waterflooding is by far the most widely used method in the world to increase oil recovery. Historically, little consideration has been given in reservoir engineering practice to the effect of injection brine composition on waterflood displacement efficiency or to the possibility of increased oil recovery through manipulation of the composition of the injected water. However, recent work has shown that oil recovery can be significantly increased by modifying the injection brine chemistry or by injecting diluted or low salinity brine. This paper reports on laboratory work done to increase the understanding of improved oil recovery by waterflooding with low salinity injection water. Porous media used in the studies included outcrop Berea sandstone (Ohio, U.S.A.) and reservoir cores from the Green River formation of the Uinta basin (Utah, U.S.A.). Crude oils used in the experimental protocols were taken from the Minnelusa formation of the Powder River basin (Wyoming, U.S.A.) and from the Green River formation, Monument Butte field in the Uinta basin. Laboratory corefloods using Berea sandstone, Minnelusa crude oil, and simulated Minnelusa formation water found a significant relationship between the temperature at which the oil- and water-saturated cores were aged and the oil recovery resulting from low salinity waterflooding. Lower aging temperatures resulted in very little to no additional oil recovery, while cores aged at higher temperatures resulted in significantly higher recoveries from dilute-water floods. Waterflood studies using reservoir cores and fluids from the Green River formation of the Monument Butte field also showed significantly higher oil recoveries from low salinity waterfloods with cores flooded with fresher water recovering 12.4% more oil on average than those flooded with undiluted formation brine.
Stored energy recovery of irradiated copper

International Nuclear Information System (INIS)

Richard, R.T.; Chaplin, R.L.; Coltman, R.R. Jr.; Kerchner, H.R.; Klabunde, C.E.

1990-01-01

The stored energy released in Stage I recovery of reactor neutron irradiated copper was measured by differential thermal analysis calorimetry for three fluences up to a maximum of 3.5 x 10 18 n/cm 2 (E>0.1 MeV) after irradiation at temperatures of less than 10 K. The dependence of the stored energy upon fluence, and a tendency toward saturation, were observed. Theoretical reaction rate processes were compared directly with the experimental rates of stored energy release, and the parameters associated with the theory were compared with results from previous resistivity measurements. Good agreement was found for several parameters, but major differences with previous D + E substage results lead to the conclusion that the point defect model may not describe materials experiencing severe neutron damage. Computer studies of warmup rates were made for first and second order and for correlated recovery processes as a function of defect concentration and of external power input. First and second order processes show definite distortion in their recovery rate curves for high defect concentrations; the correlated recovery process shows a much less pronounced effect. This investigation of stored energy used several new approaches. The use of induced radioactivity within the sample as the heating source, and the use of computer generated theoretical stored energy release curves to analyze the data were unique. (author)
Centrifugal Compressor Unit-based Heat Energy Recovery at Compressor Stations

Directory of Open Access Journals (Sweden)

V. S. Shadrin

2016-01-01

Full Text Available About 95% of the electricity consumed by air compressor stations around the world, is transformed into thermal energy, which is making its considerable contribution to global warming. The present article dwells on the re-use (recovery of energy expended for air compression.The article presents the energy analysis of the process of compressing air from the point of view of compressor drive energy conversion into heat energy. The temperature level of excess heat energy has been estimated in terms of a potential to find the ways of recovery of generated heat. It is shown that the temperature level formed by thermal energy depends on the degree of air compression and the number of stages of the compressor.Analysis of technical characteristics of modern equipment from leading manufacturers, as well as projects of the latest air compressor stations have shown that there are two directions for the recovery of heat energy arising from the air compression: Resolving technological problems of compressor units. The use of the excess heat generation to meet the technology objectives of the enterprise. This article examines the schematic diagrams of compressor units to implement the idea of heat recovery compression to solve technological problems: Heating of the air in the suction line during operation of the compressor station in winter conditions. Using compression heat to regenerate the adsorbent in the dryer of compressed air.The article gives an equity assessment of considered solutions in the total amount of heat energy of compressor station. Presented in the present work, the analysis aims to outline the main vectors of technological solutions that reduce negative impacts of heat generation of compressor stations on the environment and creating the potential for reuse of energy, i.e. its recovery.
MRI of radial displacement of the meniscus in the knee

International Nuclear Information System (INIS)

Chen Jian; Lv Houshan; Lao Shan; Guan Zhenpeng; Hong Nan; Liang Hao

2006-01-01

Objective: To describe the phenomenon of radial displacement of the meniscus of the knees in the study population with MR imaging, and to establish MRI diagnostic criteria for radial displacement of the meniscus and displacement index. Methods: MR signs of radial displacement of the meniscus were evaluated retrospectively in 398 patients with knee symptoms who were examined with non- weight bearing MR images from Jan. 2000 to Feb. 2004. The patients younger than 18 years old, with joint effusion or serious arthropathy were excluded and 312 patients were eligible to be enrolled in this study. The criterion for radial displacement of the meniscus was defined as the location of the edge of meniscal body beyond the femoral and tibial outer border line. A displacement index, defined as the ratio of meniscal overhang to meniscal width, was used to quantify meniscal displacement. Results: The prevalence of radial displacement of the meniscus was 16.7% (52/312) and 13.9% (21/151) in right knee and 19.3% (31/161 )in left knee, respectively. There was no significant difference between left and right knee (χ 2 =1.60, P>0.05) and the ratio between medial and lateral meniscus was 7.8:1. The average displacement index was 0.54±0.24. The displacement indices were significant higher in older group (F=3.63, P<0.05). The incidence and indices of radial displacement of the meniscus for patients under or above 50 year older were 12.0%(17/142), 0.46±0.22 and 20.6% (35/170), 0.64±0.20, respectively. Difference was highly significant (t=0.84, P<0.01). Conclusion: It was concluded that radial displacement of the meniscus in knees was not a rare finding with MR imaging in patients with knee symptoms. The incidence increased in older age group. Further investigations were recommended to understand the etiology and clinical significance of the phenomenon of radial displacement of the meniscus. (authors)
Overtreatment of displaced midshaft clavicle fractures

DEFF Research Database (Denmark)

Ban, Ilija; Nowak, Jan; Virtanen, Kaisa

2016-01-01

Background and purpose - The best treatment for displaced clavicle fractures has been debated for decades. Operative treatment has become more common. However, several randomized trials comparing non-operative and operative treatment have not shown any compelling evidence in favor of surgery. We...... identified the preferred treatment of displaced midshaft clavicle fractures at public hospitals in 3 countries in Scandinavia. Patients and methods - A purpose-made multiple-choice questionnaire in English was sent to all public hospitals in Denmark, Sweden, and Finland. This was addressed to the orthopedic...... surgeon responsible for treatment of clavicle fractures, and completed questionnaires were obtained from 85 of 118 hospitals. Results - In the 3 countries, 69 of the 85 hospitals that responded would treat displaced clavicle fractures operatively. Clear criteria for treatment allocation were used at 58...
Environmental Effects on Long Term Displacement Data of Woven Fabric Webbings Under Constant Load for Inflatable Structures

Science.gov (United States)

Kenner, WInfred S.; Jones, Thomas C.; Doggett, William R.; Duncan, Quinton; Plant, James

2015-01-01

tends to neutralize the annual sinusoidal displacement pattern. Study indicates that applied load, environmental effects, mechanical strength, coefficient of thermal expansion, and hygroscopic properties of webbings are fundamental requirements for quantifying accurate creep displacements and behaviors over multiple year time periods. Results from a study of the environmental effects on long-term creep displacement data of Kevlar and Vectran woven webbings are presented to increase the knowledge base of webbing materials and to enhance designs of inflatable space structures for long-duration space missions.
Performance experimental investigation of novel multifunctional nanohybrids on enhanced oil recovery

Science.gov (United States)

Gharibshahi, Reza; Jafari, Arezou; Omidkhah, Mohammadreza; Nezhad, Javad Razavi

2018-01-01

The unique characteristics of materials at the nanoscale make them a good candidate to use in the enhanced oil recovery (EOR) processes. Therefore, in this study, the effect of functionalized multi-walled carbon nanotube/silica nanohybrids on the oil recovery factor is investigated experimentally and nanofluids were injected into a glass micromodel for the first time. The nanohybrids synthesized by using sol-gel method. Micromodels as microscale apparatuses considered as 2D porous medium. Because they enable visual observation of phase displacement behavior at the pore scale. Distillated water used as the dispersion medium of nanoparticles for nanofluids preparation. A series of runs designed for flooding operations included water injection, carbon nanotube/water injection and two nanohybrids with different weight of MWCNT to the overall weight of the nanohybrid structure (10% and 70%) into the distilled water. Also, the oil recovery factor was considered as the goal parameter to compare the results. It has been found that functionalized multi-walled carbon nanotube/silica nanohybrids have a great potential in enhanced oil recovery processes. Results showed that addition of nanohybrids into distillate water causes enhancement of sweep efficiency. In other words, the fingering effect decreases and higher surface of porous medium is in contact with the injected fluid. So the higher amount of oil can produce from the porous medium consequently. By injecting nanofluid with 0.1 wt. % of carbon nanotube, the oil recovery factor increases about 11 % in comparison with water injection alone. Also by increasing the weight of MWCNT to the overall weight of the nanohybrid structure from 10% to 70%, the oil recovery factor increases from 35% to 39%.
Ab initio and Molecular Dynamic models of displacement damage in crystalline and turbostratic graphite

Science.gov (United States)

McKenna, Alice

One of the functions of graphite is as a moderator in several nuclear reactor designs, including the Advanced Gas-cooled Reactor (AGR). In the reactor graphite is used to thermalise the neutrons produced in the fission reaction thus allowing a self-sustained reaction to occur. The graphite blocks, acting as the moderator, are constantly irradiated and consequently suffer damage. This thesis examines the types of damage caused using molecular dynamic (MD) simulations and ab intio calculations. Neutron damage starts with a primary knock-on atom (PKA), which is travelling so fast that it creates damage through electronic and thermal excitation (this is addressed with thermal spike simulations). When the PKA has lost energy the subsequent cascade is based on ballistic atomic displacement. These two types of simulations were performed on single crystal graphite and other carbon structures such as diamond and amorphous carbon as a comparison. The thermal spike in single crystal graphite produced results which varied from no defects to a small number of permanent defects in the structure. It is only at the high energy range that more damage is seen but these energies are less likely to occur in the nuclear reactor. The thermal spike does not create damage but it is possible that it can heal damaged sections of the graphite, which can be demonstrated with the motion of the defects when a thermal spike is applied. The cascade simulations create more damage than the thermal spike even though less energy is applied to the system. A new damage function is found with a threshold region that varies with the square root of energy in excess of the energy threshold. This is further broken down in to contributions from primary and subsequent knock-on atoms. The threshold displacement energy (TDE) is found to be Ed=25eV at 300K. In both these types of simulation graphite acts very differently to the other carbon structures. There are two types of polycrystalline graphite structures
Recycling light metals : Optimal thermal de-coating

NARCIS (Netherlands)

Kvithyld, A.; Meskers, C.E.M.; Gaal, S.; Reuter, M.

2008-01-01

Thermal de-coating of painted and lacquered scrap is one of the new innovations developed for aluminum recycling. If implemented in all recycling and optimized as suggested in this article, recovery would be improved with considerable economic impact. Generally, contaminated scrap is difficult to
Axial displacements in external and internal implant-abutment connection.

Science.gov (United States)

Lee, Ji-Hye; Kim, Dae-Gon; Park, Chan-Jin; Cho, Lee-Ra

2014-02-01

The purpose of this study was to evaluate the axial displacement of the abutments during clinical procedures by the tightening torque and cyclic loading. Two different implant-abutment connection systems were used (external butt joint connection [EXT]; internal tapered conical connection [INT]). The master casts with two implant replicas, angulated 10° from each other, were fabricated for each implant connection system. Four types of impression copings were assembled and tightened with the corresponding implants (hex transfer impression coping, non-hex transfer impression coping, hex pick-up impression coping, non-hex pick-up impression coping). Resin splinted abutments and final prosthesis were assembled. The axial displacement was measured from the length of each assembly, which was evaluated repeatedly, after 30 Ncm torque tightening. After 250 N cyclic loading of final prosthesis for 1,000,000 cycles, additional axial displacement was recorded. The mean axial displacement was statistically analyzed (repeated measured ANOVA). There was more axial displacement in the INT group than that of the EXT group in impression copings, resin splinted abutments, and final prosthesis. Less axial displacement was found at 1-piece non-hex transfer type impression coping than other type of impression copings in the INT group. There was more axial displacement at the final prosthesis than resin splinted abutments in the INT and the EXT groups. After 250 N cyclic loading of final prosthesis, the INT group showed more axial displacement than that of the EXT group. Internal tapered conical connection demonstrated a varying amount of axial displacement with tightening torque and cyclic loading. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.
Employment protection and the consequences for displaced workers

DEFF Research Database (Denmark)

Albæk, Karsten; van Audenrode, Marc; Browning, Martin

We compare the wage and employment consequences of a job displacement in Belgium and Denmark. These two countries both have generous unemployment insurance schemes but job protection laws vary dramatically between the two. Using comparable data we find that the incidence of displacement and the c...... and the consequences for wages are similar in the two countries. The consequences for employment are very different with Danish workers experiencing much less unemployment after a displacement...
The structure and behavior of salts in kraft recovery boilers

Energy Technology Data Exchange (ETDEWEB)

Backman, R.; Badoi, R.D.; Enestam, S. [Aabo Akademi Univ., Turku (Finland). Combustion Chemistry Research Group

1997-10-01

The melting behavior in the salt system (Na,K)(CO{sub 3},SO{sub 4},S,Cl,OH) is investigated by laboratory methods to enhance and further develop a chemical model for salt mixtures with compositions relevant for recovery boilers. The model, based on both literature data and experimental work can be used as (a) submodel in models for the over-all chemistry in recovery boilers and to estimate (b) deposit formation on heat transfer surfaces (fouling), (c) the melting properties of the fly ash, and (d) the smelt bed in recovery boilers. Experimental techniques used are thermal analysis, high temperature microscopy` and scanning electron microscopy. The model is implemented in a global calculation model which can handle both gas phases and condensed phases in the recovery boiler. The model gives a detailed description of the chemical reactions involved in the fume and dust formation in different locations of the flue gas channel in the boiler. (orig.)
Bucky gel actuator displacement: experiment and model

International Nuclear Information System (INIS)

Ghamsari, A K; Zegeye, E; Woldesenbet, E; Jin, Y

2013-01-01

Bucky gel actuator (BGA) is a dry electroactive nanocomposite which is driven with a few volts. BGA’s remarkable features make this tri-layered actuator a potential candidate for morphing applications. However, most of these applications would require a better understanding of the effective parameters that influence the BGA displacement. In this study, various sets of experiments were designed to investigate the effect of several parameters on the maximum lateral displacement of BGA. Two input parameters, voltage and frequency, and three material/design parameters, carbon nanotube type, thickness, and weight fraction of constituents were selected. A new thickness ratio term was also introduced to study the role of individual layers on BGA displacement. A model was established to predict BGA maximum displacement based on the effect of these parameters. This model showed good agreement with reported results from the literature. In addition, an important factor in the design of BGA-based devices, lifetime, was investigated. (paper)
An extended collection length model for the description of keV-electron induced degradation and thermal recovery of p-i-n solar cells

International Nuclear Information System (INIS)

Schneider, U.; Schroder, B.

1990-01-01

The results of keV-electron degradation and annealing experiments obtained on a-Si:H based p-i-n solar cells are interpretated under inclusion of models developed earlier for the degradation of a-Si:H films and are placed in the framework of an extended collection length model. The strong degradation of the cell parameters j sc and FF due to considerable keV-electron irradiation can be explained quantitatively. This enables a crucial test of the validity of the mathematical models for the keV-electron induced effects developed so far. Furthermore the results of a detailed investigation of the thermal recovery of electron-degraded solar cells can be cleared up consistently. Some unresolved issues are discussed, and experiments to resolve these questions are proposed
Additive recovery at lateral boundaries of grains under electronic exposure

International Nuclear Information System (INIS)

Plotnikov, S.V.; Postnikov, D.V.

2000-01-01

The experimental investigation of additive re-distribution under electronic beam revealed a recovery of the additive at grain boundaries. Additive accumulation mainly takes place at the boundaries that are perpendicular to material surface, whereas there is no an observed recovery of additive at the boundaries that are parallel to the surface. To construe the processes of additive recovery at grain boundaries, we may use the kinetic diffusion equation describing the mass transfer processes in the presence of temperature gradients and non-equilibrium vacancies. The additive recovery is caused by spot fault gradients near the grain boundary. The grain boundary is an intensive run-off region of vacancies. Therefore, the average vacancy distribution profile near the grain boundary changes its pattern. The above case indicates that there are two additive fluxes. One of them is vectored perpendicular to the surface, and the other one is parallel to it, i.e. it is vectored to the grain boundary. A study of the perpendicular and parallel boundaries shows that there is no additive settling at the boundaries that are parallel to the surface, since the general flux is vectored to the parallel boundaries. There is no such kind of phenomenon at the grain boundaries that are perpendicular to the surface. Besides, the perpendicular boundaries are more effective run-off regions for vacancies, since there is a slower build-up of the region with vacancies due to displacement of the vacancies to the surface
Development of alkaline/surfactant/polymer (ASP flooding technology for recovery of Karazhanbas oil

Directory of Open Access Journals (Sweden)

Birzhan Zhappasbaev

2016-03-01

Full Text Available The tertiary oil recovery methods like alkaline, surfactant and polymer (ASP flooding are very perspective in order to achieve the synergetic effect out of the different impacts which are caused by these chemicals, which affect oil and water filtration in the reservoir and increase oil recovery. In this communication, we consider the applicability of hydrophobically modified polyampholyte – poly(hexadecylaminocrotonatebetaine (PHDACB as ASP flooding agent for recovery of oil from Karazhanbas oilfield. As “polysoap”, the aqueous solution of PHDACB dissolved in aqueous KOH was used. This system combines the advantages of alkaline, surfactant and polymer and exhibits the synergistic effect. The laboratory results showed that the ASP flooding considerably increases the oil recovery in addition to water flooding. In perspective, the ASP flooding may substitute the steam injection and other thermal enhanced oil recovery (EOR technologies.
Subjective study of thermal acceptability of novel enhanced displacement ventilation system and implication of occupants' personal control

DEFF Research Database (Denmark)

Sun, Weimeng; Cheong, K.W.D.; Melikov, Arsen Krikor

2012-01-01

with DV and constant heat load at different supply air temperatures, namely 20, 22, and 24 °C and room air temperatures, 22, 24, and 26 °C. Subjective assessments were carried out with 32 tropically-acclimatized college students who were given the choice to adjust the fan speed. Subjects' thermal comfort...... of 22 and 24 °C when the fans were in operation. It was also found that the Whole Body Thermal Sensation (WBTS) reported by the subjects was correlated with the Local Thermal Sensation (LTS) at the waist, the arms, the calf and the feet when the novel DV system was employed. An expression which allows...
Analysis of an integrated packed bed thermal energy storage system for heat recovery in compressed air energy storage technology

International Nuclear Information System (INIS)

Ortega-Fernández, Iñigo; Zavattoni, Simone A.; Rodríguez-Aseguinolaza, Javier; D'Aguanno, Bruno; Barbato, Maurizio C.

2017-01-01

Highlights: •A packed bed TES system is proposed for heat recovery in CAES technology. •A CFD-based approach has been developed to evaluate the behaviour of the TES unit. •TES system enhancement and improvement alternatives are also demonstrated. •TES performance evaluated according to the first and second law of thermodynamics. -- Abstract: Compressed air energy storage (CAES) represents a very attracting option to grid electric energy storage. Although this technology is mature and well established, its overall electricity-to-electricity cycle efficiency is lower with respect to other alternatives such as pumped hydroelectric energy storage. A meager heat management strategy in the CAES technology is among the main reasons of this gap of efficiency. In current CAES plants, during the compression stage, a large amount of thermal energy is produced and wasted. On the other hand, during the electricity generation stage, an extensive heat supply is required, currently provided by burning natural gas. In this work, the coupling of both CAES stages through a thermal energy storage (TES) unit is introduced as an effective solution to achieve a noticeable increase of the overall CAES cycle efficiency. In this frame, the thermal energy produced in the compression stage is stored in a TES unit for its subsequent deployment during the expansion stage, realizing an Adiabatic-CAES plant. The present study addresses the conceptual design of a TES system based on a packed bed of gravel to be integrated in an Adiabatic-CAES plant. With this objective, a complete thermo-fluid dynamics model has been developed, including the implications derived from the TES operating under variable-pressure conditions. The formulation and treatment of the high pressure conditions were found being particularly relevant issues. Finally, the model provided a detailed performance and efficiency analysis of the TES system under charge/discharge cyclic conditions including a realistic operative
Lingual nerve injury in third molar surgery I. Observations on recovery of sensation with spontaneous healing

DEFF Research Database (Denmark)

Hillerup, S; Stoltze, Kaj

2007-01-01

, thermal stimuli and location of stimulus, as well as two-point discrimination, pain and the presence of a neuroma at the lesion site. Neurogenic signs and symptoms related to the injury and their variation over time were registered. Females were more often referred than males. Most lingual nerve injuries...... exhibited a significant potential for recovery, but only a few patients made a full recovery with absence of neurogenic symptoms. The recovery rate was highest during the first 6 months. Recovery was not influenced by gender, and only slightly by age. The presence of a neuroma was associated with a more...
A Vision-Based Sensor for Noncontact Structural Displacement Measurement

Science.gov (United States)

Feng, Dongming; Feng, Maria Q.; Ozer, Ekin; Fukuda, Yoshio

2015-01-01

Conventional displacement sensors have limitations in practical applications. This paper develops a vision sensor system for remote measurement of structural displacements. An advanced template matching algorithm, referred to as the upsampled cross correlation, is adopted and further developed into a software package for real-time displacement extraction from video images. By simply adjusting the upsampling factor, better subpixel resolution can be easily achieved to improve the measurement accuracy. The performance of the vision sensor is first evaluated through a laboratory shaking table test of a frame structure, in which the displacements at all the floors are measured by using one camera to track either high-contrast artificial targets or low-contrast natural targets on the structural surface such as bolts and nuts. Satisfactory agreements are observed between the displacements measured by the single camera and those measured by high-performance laser displacement sensors. Then field tests are carried out on a railway bridge and a pedestrian bridge, through which the accuracy of the vision sensor in both time and frequency domains is further confirmed in realistic field environments. Significant advantages of the noncontact vision sensor include its low cost, ease of operation, and flexibility to extract structural displacement at any point from a single measurement. PMID:26184197

Presentation of the project Thermal processes with energy recovery for sludge and special or hazardous waste disposal

International Nuclear Information System (INIS)

Mininni, G.; Passino, R.

2001-01-01

Main results obtained in the framework of the project Thermal processes with energy recovery for sludge and special waste (also hazardous) disposal granted for 2.16 M Euro by the Italian Ministry of Education through Structural Funds are reported. This project is subdivided into the following four main sub projects: combustion of hazardous sludges on a demonstrative plant; combustion of sludges in fluidized bed reactors on pilot and laboratory scale; set up of a flue gas sampling device at high temperature; fluid dynamic modelling of combustion. Original and interesting results were produced mainly connected with the following aspects: combined incineration of sewage and hazardous sludges appeared to be reliable considering that gaseous emissions did not show any deterioration following the addition of chlorinated hydrocarbons to sewage sludge. Gaseous emissions were found to be not conform with the standards only in very few cases generally not linked with critical conditions: polynuclear aromatic hydrocarbons (PAHs) were found to be a reliable parameter for emissions monitoring considering that they are produced in abundance following up set conditions due to a temperature decline or an insufficient oxygen supply; the very stringent limit at the emissions of 0.1 ng/m 3 for dioxins and furans (TE) can be respected in the most of the cases but this monitoring is very complex, time consuming and expensive. Sampling and extraction errors might considerably impact the measured value, which is much more dependent on the conditions inside the recovery boiler rather than on the combustion efficiency; metals are enriched onto the fly ashes produced in the tests carried out by rotating drum furnace more than in the tests by fluidized bed furnace; after burning chamber mode of operation did not display a direct influence on the emissions; incineration tests carried out on reduced pilot scale have shown a total absence of fragmentation during volatilisation while particulate
Fabrication of dendritic silver-coated copper powders by galvanic displacement reaction and their thermal stability against oxidation

International Nuclear Information System (INIS)

Park, Yu-Seon; An, Chang Yong; Kannan, Padmanathan Karthick; Seo, Nary; Zhuo, Kai; Yoo, Tae Kyong; Chung, Chan-Hwa

2016-01-01

Highlights: • The dendritic silver-coated copper powders with high specific surface area have been prepared using a simple wet chemical reduction process at room temperature. • It is found that the Cu starts to be oxidized into Cu_2O followed by CuO at elevated temperatures. • The more amount of Ag-coating provides the less oxidation, which confirms that the Ag-shell prevents the Cu-core from oxidation. • The resistivity of dendritic 33.27 wt.% Ag-coated Cu powders was measured to 25.67 μΩ cm after the annealing at 150 °C for 30 min. - Abstract: Two steps of wet chemical processes have been developed for the preparation of core-shell nanostructures of copper and silver, which is a facile and low cost method for the production of large quantity of dendritic powders. First step involves a galvanic displacement reaction with hydrogen evolution which is the motive force of spontaneous electrochemical reaction. To achieve the core-shell structure, silver has been coated on the dendritic copper using the galvanic displacement reaction. The dendritic silver-coated copper powders exhibit high surface-area, excellent conductivity, and good oxidation resistance. It has been found that silver-coated copper powders maintain the electrical conductivity even after annealing at 150 °C for several to tens of minutes, thus it is a promising material and an alternative to pure silver powders in printed electronics application.
Fabrication of dendritic silver-coated copper powders by galvanic displacement reaction and their thermal stability against oxidation

Energy Technology Data Exchange (ETDEWEB)

Park, Yu-Seon [School of Chemical Engineering, Sungkyunkwan University, Suwon 16419 (Korea, Republic of); Farad Materials Co., Ltd., Suwon 16419 (Korea, Republic of); An, Chang Yong; Kannan, Padmanathan Karthick; Seo, Nary [School of Chemical Engineering, Sungkyunkwan University, Suwon 16419 (Korea, Republic of); Zhuo, Kai [School of Chemical Engineering, Sungkyunkwan University, Suwon 16419 (Korea, Republic of); Farad Materials Co., Ltd., Suwon 16419 (Korea, Republic of); Yoo, Tae Kyong [School of Chemical Engineering, Sungkyunkwan University, Suwon 16419 (Korea, Republic of); Chung, Chan-Hwa, E-mail: chchung@skku.edu [School of Chemical Engineering, Sungkyunkwan University, Suwon 16419 (Korea, Republic of); Farad Materials Co., Ltd., Suwon 16419 (Korea, Republic of)

2016-12-15

Highlights: • The dendritic silver-coated copper powders with high specific surface area have been prepared using a simple wet chemical reduction process at room temperature. • It is found that the Cu starts to be oxidized into Cu{sub 2}O followed by CuO at elevated temperatures. • The more amount of Ag-coating provides the less oxidation, which confirms that the Ag-shell prevents the Cu-core from oxidation. • The resistivity of dendritic 33.27 wt.% Ag-coated Cu powders was measured to 25.67 μΩ cm after the annealing at 150 °C for 30 min. - Abstract: Two steps of wet chemical processes have been developed for the preparation of core-shell nanostructures of copper and silver, which is a facile and low cost method for the production of large quantity of dendritic powders. First step involves a galvanic displacement reaction with hydrogen evolution which is the motive force of spontaneous electrochemical reaction. To achieve the core-shell structure, silver has been coated on the dendritic copper using the galvanic displacement reaction. The dendritic silver-coated copper powders exhibit high surface-area, excellent conductivity, and good oxidation resistance. It has been found that silver-coated copper powders maintain the electrical conductivity even after annealing at 150 °C for several to tens of minutes, thus it is a promising material and an alternative to pure silver powders in printed electronics application.
Displacement control of an antagonistic-type twisted and coiled polymer actuator

Science.gov (United States)

Suzuki, Motoya; Kamamichi, Norihiro

2018-03-01

A novel artificial muscle actuator referred to as a twisted and coiled polymer actuator can be easily fabricated by commercially available nylon fibers. It can be thermally activated and has remarkable properties such as large deformation and flexibility. The actuator uses conductive nylon fibers and can be activated by Joule heating and is easily controlled electrically. However, asymmetric response characteristics due to a speed difference in heating-cooling are a problem. In the case of actuation in air, the cooling speed depends on the external temperature, and is slower than the heating speed. To solve these problems, we apply an antagonistic structure. The validity of the applied method is investigated through numerical simulations and experiments. The response characteristics of the PID feedback control and the 2-DOF control of the displacement are investigated.
Neutron-induced displacement damage analysis (with particular reference to zirconium)

International Nuclear Information System (INIS)

Woo, C.H.

1978-10-01

Neutron irradiation produces damage in a solid, initially in the form of atomic displacements. As a first step to understanding the effects of irradiation damage in reactor structural materials, information on the initial atomic displacements is necessary. The computer program DISPKAN, based on an extension and generalization of the program RICE, written at ORNL for such calculations, has been developed and installed on the CDC system at CRNL. Using neutron scattering data from ENDF/B files, DISPKAN performs a displacement and PKO analysis on the initial damage caused by neutrons from a given spectrum. The following quantities are calculated: the displacement rate per unit neutron flux, the PKO spectrum, the displacement spectrum, the fraction of PKO's with energy above T, the fraction of displacements produced by PKO's with energy above T, the average PKO energy, the average number of displacements produced per PKO, and the total number of PKO's produced per atom of the solid per unit fluence. The input and output formats of the program are explained. Sample runs are demonstrated. Results for zirconium, exposed to five neutron spectra typically available to experimentalist, are given to illustrate the spectral dependence of the initial displacement events. (author)
Analysis of vehicle exhaust waste heat recovery potential using a Rankine cycle

International Nuclear Information System (INIS)

Domingues, António; Santos, Helder; Costa, Mário

2013-01-01

This study evaluates the vehicle exhaust WHR (waste heat recovery) potential using a RC (Rankine cycle ). To this end, both a RC thermodynamic model and a heat exchanger model have been developed. Both models use as input, experimental data obtained from a vehicle tested on a chassis dynamometer. The thermodynamic analysis was performed for water, R123 and R245fa and revealed the advantage of using water as the working fluid in applications of thermal recovery from exhaust gases of vehicles equipped with a spark-ignition engine. Moreover, the heat exchanger effectiveness for the organic working fluids R123 and R245fa is higher than that for the water and, consequently, they can also be considered appropriate for use in vehicle WHR applications through RCs when the exhaust gas temperatures are relatively low. For an ideal heat exchanger, the simulations revealed increases in the internal combustion engine thermal and vehicle mechanical efficiencies of 1.4%–3.52% and 10.16%–15.95%, respectively, while for a shell and tube heat exchanger, the simulations showed an increase of 0.85%–1.2% in the thermal efficiency and an increase of 2.64%–6.96% in the mechanical efficiency for an evaporating pressure of 2 MPa. The results confirm the advantages of using the thermal energy contained in the vehicle exhaust gases through RCs. Furthermore, the present analysis demonstrates that improved evaporator designs and appropriate expander devices allowing for higher evaporating pressures are required to obtain the maximum WHR potential from vehicle RC systems. -- Highlights: ► This study evaluates the vehicle exhaust waste heat recovery potential using Rankine cycle systems. ► A thermodynamic model and a heat exchanger model were developed. ► Experimental data obtained in a vehicle tested on a chassis dynamometer was used as models input. ► Thermodynamic analysis was performed for water, R123 and R245fa. ► Results confirm advantages of using the thermal energy
Economical photovoltaic power generation with heat recovery

Science.gov (United States)

Ascher, G.

1977-01-01

Three designs for conversion of solar radiation to electricity and thermal energy are analyzed. The objective of these converters is to increase the electric and thermal output for each photovoltaic array so as to lower the cell cost relative to the amount of energy delivered. An analysis of the economical aspects of conversion by photovoltaic cells with heat recovery is carried out in terms of hypothetical examples. Thus, it is shown that the original cost of say $40,000 per generated kilowat can be reduced to $572.00 per kilowatt by increasing the original electric output of 1 kW to 10 kW in electricity and 60 kW in thermal energy. The newly derived specific cost is only 1.4 percent of the original one. It is expected that a cost reduction of roughly 2% of the present specific cost per kilowatt will greatly stimulate public acceptance of photovoltaic terrestrial conversion to electricity.
Application of a novel Kalman filter based block matching method to ultrasound images for hand tendon displacement estimation.

Science.gov (United States)

Lai, Ting-Yu; Chen, Hsiao-I; Shih, Cho-Chiang; Kuo, Li-Chieh; Hsu, Hsiu-Yun; Huang, Chih-Chung

2016-01-01

Information about tendon displacement is important for allowing clinicians to not only quantify preoperative tendon injuries but also to identify any adhesive scaring between tendon and adjacent tissue. The Fisher-Tippett (FT) similarity measure has recently been shown to be more accurate than the Laplacian sum of absolute differences (SAD) and Gaussian sum of squared differences (SSD) similarity measures for tracking tendon displacement in ultrasound B-mode images. However, all of these similarity measures can easily be influenced by the quality of the ultrasound image, particularly its signal-to-noise ratio. Ultrasound images of injured hands are unfortunately often of poor quality due to the presence of adhesive scars. The present study investigated a novel Kalman-filter scheme for overcoming this problem. Three state-of-the-art tracking methods (FT, SAD, and SSD) were used to track the displacements of phantom and cadaver tendons, while FT was used to track human tendons. These three tracking methods were combined individually with the proposed Kalman-filter (K1) scheme and another Kalman-filter scheme used in a previous study to optimize the displacement trajectories of the phantom and cadaver tendons. The motion of the human extensor digitorum communis tendon was measured in the present study using the FT-K1 scheme. The experimental results indicated that SSD exhibited better accuracy in the phantom experiments, whereas FT exhibited better performance for tracking real tendon motion in the cadaver experiments. All three tracking methods were influenced by the signal-to-noise ratio of the images. On the other hand, the K1 scheme was able to optimize the tracking trajectory of displacement in all experiments, even from a location with a poor image quality. The human experimental data indicated that the normal tendons were displaced more than the injured tendons, and that the motion ability of the injured tendon was restored after appropriate rehabilitation
Diagnosing displaced four-part fractures of the proximal humerus

DEFF Research Database (Denmark)

Brorson, Stig; Bagger, Jens; Sylvest, Annette

2009-01-01

Displaced four-part fractures comprise 2-10 % of all proximal humeral fractures. The optimal treatment is unclear and randomised trials are needed. The conduct and interpretation of such trials is facilitated by a reproducible fracture classification. We aimed at quantifying observer agreement...... on the classification of displaced four-part fractures according to the Neer system. Published and unpublished data from five observer studies were reviewed. Observers agreed less on displaced four-part fractures than on the overall Neer classification. Mean kappa values for interobserver agreement ranged from 0.......16 to 0.48. Specialists agreed slightly more than fellows and residents. Advanced imaging modalities (CT and 3D CT) seemed to contribute more to classification of displaced four-part patterns than in less complex fracture patterns. Low observer agreement may challenge the clinical approach to displaced...
Land Restitution and Prevention of Forced Displacement in Colombia

Directory of Open Access Journals (Sweden)

Felipe Gómez-Isa

2010-11-01

Full Text Available The armed conflict in Colombia, which has generated over three million internally displaced persons, has dramatic humanitarian consequences and raises serious issues regarding the protection of displaced peoples’ rights. The underlying reasons for the displacement often lie in the dynamics associated with territorial control and land seizures undertaken for strategic, military or purely economic purposes. Domestic and international legal provisions have established the victims’ right to the restitution of their homes and property as the “preferred remedy” in cases of displacement. However, policies dealing with displacement, both those of the Colombian government and of several international institutions, fail to take this sufficiently into account. A comprehensive reparation policy for victims must necessarily entail the reversion of lands, territories and goods seized in Colombia under the pretext of the internal armed conflict.
Method of making self-calibrated displacement measurements

International Nuclear Information System (INIS)

Pedersen, H.N.

1977-01-01

A method for monitoring the displacement of an object having an acoustically reflective surface at least partially submerged in an acoustically conductive medium is described. The reflective surface is designed to have a stepped interface responsive to an incident acoustic pulse to provide separate discrete reflected pulses to a receiving transducer. The difference in the time of flight of the reflected acoustic signals corresponds to the known step height and the time of travel of the signals to the receiving transducer provides a measure of the displacement of the object. Accordingly, the reference step length enables simultaneous calibration of each displacement measurement. 3 claims, 3 figures
Experimental studies of thermal preparation of internal combustion engine

Science.gov (United States)

Karnaukhov, N. N.; Merdanov, Sh M.; V, Konev V.; Borodin, D. M.

2018-05-01

In conditions of autonomous functioning of road construction machines, it becomes necessary to use its internal sources. This can be done by using a heat recovery system of an internal combustion engine (ICE). For this purpose, it is proposed to use heat accumulators that accumulate heat of the internal combustion engine during the operation of the machine. Experimental studies have been carried out to evaluate the efficiency of using the proposed pre-start thermal preparation system, which combines a regular system based on liquid diesel fuel heaters and an ICE heat recovery system. As a result, the stages of operation of the preheating thermal preparation system, mathematical models and the dependence of the temperature change of the antifreeze at the exit from the internal combustion engine on the warm-up time are determined.
Mental health of internally displaced persons in Jalozai camp, Pakistan.

Science.gov (United States)

Mujeeb, Arooj

2015-11-01

Internal displacement has been a distressing issue of Pakistan for last one decade. Few research works have been conducted on the psychological issues of internally displaced persons in Pakistan. The current research was aimed at determining the psychological effects of internal displacement, that is, psychological well-being, depression, anxiety and stress (internalizing problems) of the individuals who were displaced as a result of an armed conflict in Swat. A sample of 126 internally displaced persons was taken from Jalozai camp which included females (n = 65) and males (n = 61). Age of the sample ranged from 20 to 75 years with a mean of 47.5 years. Translated and adapted versions of Well-Being Affectometer-2 Scale and Depression Anxiety Stress Scale were used in the current research. Results of the study indicated differences between males and females, females being higher on internalizing problems and lower on psychological well-being, whereas family loss during displacement affected the results in the same way. Well-being, gender and family loss emerged as significant predictors of internalizing problems, and gender moderated the relationship between well-being and internalizing problems. Internal displacement may bring psychological issues for internally displaced persons, that is, their well-being may decrease and depression, anxiety and stress may increase during displacement. Limitations and implications of the study were discussed further. © The Author(s) 2015.
Investigation of Chemical-Foam Design as a Novel Approach toward Immiscible Foam Flooding for Enhanced Oil Recovery.

Science.gov (United States)

Hosseini-Nasab, S M; Zitha, P L J

2017-10-19

Strong foam can be generated in porous media containing oil, resulting in incremental oil recovery; however, oil recovery factor is restricted. A large fraction of oil recovered by foam flooding forms an oil-in-water emulsion, so that costly methods may need to be used to separate the oil. Moreover, strong foam could create a large pressure gradient, which may cause fractures in the reservoir. This study presents a novel chemical-foam flooding process for enhanced oil recovery (EOR) from water-flooded reservoirs. The presented method involved the use of chemically designed foam to mobilize the remaining oil after water flooding and then to displace the mobilized oil to the production well. A blend of two anionic surfactant formulations was formulated for this method: (a) IOS, for achieving ultralow interfacial tension (IFT), and (b) AOS, for generating a strong foam. Experiments were performed using Bentheimer sandstone cores, where X-ray CT images were taken during foam generation to find the stability of the advancing front of foam propagation and to map the gas saturation for both the transient and the steady-state flow regimes. Then the proposed chemical-foam strategy for incremental oil recovery was tested through the coinjection of immiscible nitrogen gas and surfactant solutions with three different formulation properties in terms of IFT reduction and foaming strength capability. The discovered optimal formulation contains a foaming agent surfactant, a low IFT surfactant, and a cosolvent, which has a high foam stability and a considerably low IFT (1.6 × 10 -2 mN/m). Coinjection resulted in higher oil recovery and much less MRF than the same process with only using a foaming agent. The oil displacement experiment revealed that coinjection of gas with a blend of surfactants, containing a cosolvent, can recover a significant amount of oil (33% OIIP) over water flooding with a larger amount of clean oil and less emulsion.
ECOLOGY SAFETY TECHNOLOGIES OF UNCONVENTIONAL OIL RESERVES RECOVERY FOR SUSTAINABLE OIL AND GAS INDUSTRY DEVELOPMENT

Directory of Open Access Journals (Sweden)

Viacheslav Zyrin

2016-09-01

Full Text Available The problem of effective technology for heavy oil recovery nowadays has a great importance, because of worsening geological conditions of the developed deposits, decreasing recovery factor, increasing the part of heavy oil. For the future sustainable development of oil producing industry the involved technologies must require energy effectiveness and ecological safety. The paper proves the enhanced oil recovery methods necessity for heavy oil deposits, highlighted thermal technologies as the most effective. But traditional thermal treatment technologies is a source of air pollutant emission, such as CO, NO etc. The calculation of emissions for traditional steam generator is provided. Besides, the paper shows the effectiveness of electrical enhanced oil recovery methods. The advantages of associated gas as a fuel for cogeneration plants is shown. The main approaches to implementation of carbon dioxide sequestration technologies in the oil and gas industry of Russia are defined. Conceptual view of СО2-EOR technologies potential within the context of sustainable development of oil and gas industry are presented. On the basis of the conducted research a number of scientific research and practical areas of the CCS technology development are revealed.
[Displacement of the posterior part of the eyeball in myopia].

Science.gov (United States)

Akizawa, Yasuko; Masahiro, Ida

2006-12-01

The principal aim of this study was to investigate displacement of the posterior part of the eyeball within the muscle cone in myopic eyes, particularly in moderately myopic subjects as well as in high myopes. Secondly, the correlation of the amount of displacement and the outer axial length of the globe was studied. The direction of displacement was also examined to clarify whether the eyeball tends to shift toward a certain direction. Seven patients with moderate myopia (moderate myopia group), fifteen patients with high myopia without esotropia (high myopia group), five patients with high myopia and esotropia (myopic esotropia group), and twenty-two controls (control group) were examined. Using magnetic resonance imaging, the outer axial length and the displacement of the posterior portion of the eyeball in the muscle cone were measured. In order to eliminate interindividual differences in the facial configuration, the coronal scanning was done perpendicularly to the orbital axis. The displacement was measured in a plane 4 mm anterior to the globe-optic nerve junction. The displacement was represented by the distance and direction of the globe center from the center of the muscle cone. In the moderate myopia group, there was no displacement of the posterior part of the eyeball in the muscle cone. It was the same as in the control group. But among the three groups, the displacement (mean standard deviation) was significantly greater in the myopic esotropia group (1.53 +/- 0.49 mm) and the high myopia group (0.94 +/- 0.52 mm) than in the control group (0.11 +/- 0.18 mm) (one way ANOVA and multiple comparison). The outer axial length and the distance of the displacement in all cases was significantly correlated (r = 0.87, p = 0.01). Moreover, the posterior part of the eyeball of the myopic esotropia group and the high myopia group was displaced superiorly and temporally. The posterior part of the eyeball of myopic eyes was displaced superotemporally in the muscle
Algebraic motion of vertically displacing plasmas

Science.gov (United States)

Bhattacharjee, Amitava; Pfefferle, David; Hirvijoki, Eero

2017-10-01

The vertical displacement of tokamak plasmas is modelled during the non-linear phase by a free-moving current-carrying rod coupled to a set of fixed conducting wires and a cylindrical conducting shell. The models capture the leading term in a Taylor expansion of the Green's function for the interaction between the plasma column and the vacuum vessel. The plasma is assumed not to vary during the VDE such that it behaves as a rigid body. In the limit of perfectly conducting structures, the plasma is prevented from coming in contact with the wall due to steep effective potential barriers by the eddy currents, and will hence oscillate at Alfvénic frequencies about a given force-free position. In addition to damping oscillations, resistivity allows for the column to drift towards the vessel on slow flux penetration timescales. The initial exponential motion of the plasma, i.e. the resistive vertical instability, is succeeded by a non-linear sinking behaviour, that is shown analytically to be algebraic and decelerative. The acceleration of the plasma column often observed in experiments is thus conjectured to originate from an early sharing of toroidal current between the core, the halo plasma and the wall or from the thermal quench dynamics precipitating loss of plasma current
Quantification of the vocal folds’ dynamic displacements

Science.gov (United States)

del Socorro Hernández-Montes, María; Muñoz, Silvino; De La Torre, Manuel; Flores, Mauricio; Pérez, Carlos; Mendoza-Santoyo, Fernando

2016-05-01

Fast dynamic data acquisition techniques are required to investigate the motional behavior of the vocal folds (VFs) when they are subjected to a steady air-flow through the trachea. High-speed digital holographic interferometry (DHI) is a non-invasive full-field-of-view technique that has proved its usefulness to study rapid and non-repetitive object movements. Hence it is an ideal technique used here to measure VF displacements and vibration patterns at 2000 fps. Analyses from a set of 200 displacement images showed that VFs’ vibration cycles are established along their width (y) and length (x). Furthermore, the maximum deformation for the right and left VFs’ area may be quantified from these images, which in itself represents an important result in the characterization of this structure. At a controlled air pressure, VF displacements fall within the range ~100-1740 nm, with a calculated precision and accuracy that yields a variation coefficient of 1.91%. High-speed acquisition of full-field images of VFs and their displacement quantification are on their own significant data in the study of their functional and physiological behavior since voice quality and production depend on how they vibrate, i.e. their displacement amplitude and frequency. Additionally, the use of high speed DHI avoids prolonged examinations and represents a significant scientific and technological alternative contribution in advancing the knowledge and working mechanisms of these tissues.
Lateral vibration analysis of continuous bridges utilizing equal displacement rule

Directory of Open Access Journals (Sweden)

Biao Wei

Full Text Available The application of equal displacement rule simplifies the evaluation of lateral displacement demand forSDOF system. For complex multi-degree-of-freedom (MDOF structures such as continuous bridge systems, however, it requires more investigations. In this paper, a comprehensive parametric study of the ratio of maximum inelastic displacement to maximum elastic displacement for typical continuous bridges is performedto advance the application of equal displacement rule to MDOF systems. Particurlarly for the bridges with long periods, this adapted methodlogy is further simplified. It is concluded that equal displacement rule of MDOF is applicable to continuous bridges when the periods of the main modes are no less than the limiting period, which usually serves as an indication to the level of inelastic deformation for a bridge subjected to an earthquake.
Sacrificial adsorbate for surfactants utilized in chemical floods of enhanced oil recovery operations

Science.gov (United States)

Johnson, Jr., James S.; Westmoreland, Clyde G.

1982-01-01

The present invention is directed to a sacrificial or competitive adsorbate for surfactants contained in chemical flooding emulsions for enhanced oil recovery operations. The adsorbate to be utilized in the method of the present invention is a caustic effluent from the bleach stage or the weak black liquor from the digesters and pulp washers of the kraft pulping process. This effluent or weak black liquor is injected into an oil-bearing subterranean earth formation prior to or concurrent with the chemical flood emulsion and is adsorbed on the active mineral surfaces of the formation matrix so as to effectively reduce adsorption of surfactant in the chemical flood. Alternatively, the effluent or liquor can be injected into the subterranean earth formation subsequent to a chemical flood to displace the surfactant from the mineral surfaces for the recovery thereof.

Removing oxygen from a solvent extractant in an uranium recovery process

International Nuclear Information System (INIS)

Hurst, F.J.; Brown, G.M.; Posey, F.A.

1984-01-01

An improvement in effecting uranium recovery from phosphoric acid solutions is provided by sparging dissolved oxygen contained in solutions and solvents used in a reductive stripping stage with an effective volume of a nonoxidizing gas before the introduction of the solutions and solvents into the stage. Effective volumes of nonoxidizing gases, selected from the group consisting of argon, carbon dioxide, carbon monoxide, helium, hydrogen, nitrogen, sulfur dioxide, and mixtures thereof, displace oxygen from the solutions and solvents thereby reduce deleterious effects of oxygen such as excessive consumption of elemental or ferrous and accumulation of complex iron phosphates or cruds
Aquifer thermal-energy-storage modeling

Science.gov (United States)

Schaetzle, W. J.; Lecroy, J. E.

1982-09-01

A model aquifer was constructed to simulate the operation of a full size aquifer. Instrumentation to evaluate the water flow and thermal energy storage was installed in the system. Numerous runs injecting warm water into a preconditioned uniform aquifer were made. Energy recoveries were evaluated and agree with comparisons of other limited available data. The model aquifer is simulated in a swimming pool, 18 ft by 4 ft, which was filled with sand. Temperature probes were installed in the system. A 2 ft thick aquifer is confined by two layers of polyethylene. Both the aquifer and overburden are sand. Four well configurations are available. The system description and original tests, including energy recovery, are described.
Neutron induced displacement damage in beryllium in the blanket of a (d,t)-fusion reactor

International Nuclear Information System (INIS)

Hermanutz, D.

1995-09-01

Beryllium is a favoured candidate for a neutron multiplier in solid breeder blankets of fusion reactors. This is mainly due to its low (n, 2n)-reaction threshold and because of its good thermal and mechanical properties. Its behaviour under intense neutron irradiation, however, is a crucial issue for its use in future fusion reactors. Displacement damage in beryllium so far has been calculated both with data related and methodological deficiencies. First of all, there is a need to have accurate cross-section data in order to obtain reliable spectra of primary knock-on atoms (PKA's). Furthermore, there are principal restrictions of the NRT-model in general used to calculate secondary displacements initiated by PKA's. The underlying theory of damage-energy (part of kinetic energy of PKA transferred elastically to matrix atoms) according to Lindhard is strictly valid only for medium and heavy mass ions with moderate energies in targets of the same element. In this work improved damage cross-sections and displacement rates (dpa/s) in beryllium have been calculated based on cross-section data from ENDF/B-VI (with a significantly improved (n, 2n)-evaluation) and on an appropriate treatment of damage-energy that is suitable for fusion relevant damage of light mass materials. ''This work has been performed in the framework of the Nuclear Fusion Project of the Forschungszentrum Karlsruhe and is supported by the European Communities within the European Fusion Technology Program''. (orig.)
Large scale chromatographic separations using continuous displacement chromatography (CDC)

International Nuclear Information System (INIS)

Taniguchi, V.T.; Doty, A.W.; Byers, C.H.

1988-01-01

A process for large scale chromatographic separations using a continuous chromatography technique is described. The process combines the advantages of large scale batch fixed column displacement chromatography with conventional analytical or elution continuous annular chromatography (CAC) to enable large scale displacement chromatography to be performed on a continuous basis (CDC). Such large scale, continuous displacement chromatography separations have not been reported in the literature. The process is demonstrated with the ion exchange separation of a binary lanthanide (Nd/Pr) mixture. The process is, however, applicable to any displacement chromatography separation that can be performed using conventional batch, fixed column chromatography
Effect of excavation method on rock mass displacement

International Nuclear Information System (INIS)

Sato, Toshinori; Kikuchi, Tadashi; Sugihara, Kozo

1998-01-01

Rock mass displacement measurements have been performed to understand rock mass behavior and its dependence on excavation method during drift excavation at the Tono mine. Rock mass displacements of 1.46 mm and 0.67 mm have been measured at one meter (0.33D: blasting, 0.42D: machine, D: width of drift) from the walls of drifts excavated by the drill and blasting method and machine, respectively. Numerical analysis of rock mass displacements with Finite Element Method has been performed assuming an excavation disturbed zone. Measured and analysed rock mass displacements are consistent with each other for the drift excavation by the drill and blasting method. The excavation disturbed zone was narrower for the drift excavated by machine than for the drift excavated by the drill and blasting method. (author)
Pitot-probe displacement in a supersonic turbulent boundary layer

Science.gov (United States)

Allen, J. M.

1972-01-01

Eight circular pitot probes ranging in size from 2 to 70 percent of the boundary-layer thickness were tested to provide experimental probe displacement results in a two-dimensional turbulent boundary layer at a nominal free-stream Mach number of 2 and unit Reynolds number of 8 million per meter. The displacement obtained in the study was larger than that reported by previous investigators in either an incompressible turbulent boundary layer or a supersonic laminar boundary layer. The large probes indicated distorted Mach number profiles, probably due to separation. When the probes were small enough to cause no appreciable distortion, the displacement was constant over most of the boundary layer. The displacement in the near-wall region decreased to negative displacement in some cases. This near-wall region was found to extend to about one probe diameter from the test surface.
Neutron diffraction determination of mean-square atomic displacements

International Nuclear Information System (INIS)

Tibballs, J.E.; Feteris, S.M.; Barnea, Z.

1981-01-01

Integrated intensities for Bragg reflection of neutrons from single crystals of the III-V compounds, InAs and GaSb, have been measured at room temperature. The data were collected at two wavelengths, 0.947 A and 1.241 A, in order to establish the adequacy of a correction for moderate to severe anisotropic extinction. Data were also obtained for InAs at four temperatures from 408 K to 933 K. Corrections for thermal diffuse scattering were applied. The results were analysed in the one-particle potential approximation with terms to fourth-order in the atomic displacements u = (u 1 , u 2 , u 3 ). At 296 K, the mean-square components were determined for In, 0.0116(2)A 2 and As, 0.0102 (1)A 2 ; for Ga, 0.0120(3)A 2 and Sb, 0.0107(3)A 2 . The third-order coefficients for InAs are comparable with those for Si and Ge, those for GaSb with those for zinc chalcogenides. Non-harmonic behaviour in InAs is observed below 400 K
The Effect of Basepair Mismatch on DNA Strand Displacement.

Science.gov (United States)

Broadwater, D W Bo; Kim, Harold D

2016-04-12

DNA strand displacement is a key reaction in DNA homologous recombination and DNA mismatch repair and is also heavily utilized in DNA-based computation and locomotion. Despite its ubiquity in science and engineering, sequence-dependent effects of displacement kinetics have not been extensively characterized. Here, we measured toehold-mediated strand displacement kinetics using single-molecule fluorescence in the presence of a single basepair mismatch. The apparent displacement rate varied significantly when the mismatch was introduced in the invading DNA strand. The rate generally decreased as the mismatch in the invader was encountered earlier in displacement. Our data indicate that a single base pair mismatch in the invader stalls branch migration and displacement occurs via direct dissociation of the destabilized incumbent strand from the substrate strand. We combined both branch migration and direct dissociation into a model, which we term the concurrent displacement model, and used the first passage time approach to quantitatively explain the salient features of the observed relationship. We also introduce the concept of splitting probabilities to justify that the concurrent model can be simplified into a three-step sequential model in the presence of an invader mismatch. We expect our model to become a powerful tool to design DNA-based reaction schemes with broad functionality. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.
An Exogenous Surfactant-Producing Bacillus subtilis Facilitates Indigenous Microbial Enhanced Oil Recovery.

Science.gov (United States)

Gao, Peike; Li, Guoqiang; Li, Yanshu; Li, Yan; Tian, Huimei; Wang, Yansen; Zhou, Jiefang; Ma, Ting

2016-01-01

This study used an exogenous lipopeptide-producing Bacillus subtilis to strengthen the indigenous microbial enhanced oil recovery (IMEOR) process in a water-flooded reservoir in the laboratory. The microbial processes and driving mechanisms were investigated in terms of the changes in oil properties and the interplay between the exogenous B. subtilis and indigenous microbial populations. The exogenous B. subtilis is a lipopeptide producer, with a short growth cycle and no oil-degrading ability. The B. subtilis facilitates the IMEOR process through improving oil emulsification and accelerating microbial growth with oil as the carbon source. Microbial community studies using quantitative PCR and high-throughput sequencing revealed that the exogenous B. subtilis could live together with reservoir microbial populations, and did not exert an observable inhibitory effect on the indigenous microbial populations during nutrient stimulation. Core-flooding tests showed that the combined exogenous and indigenous microbial flooding increased oil displacement efficiency by 16.71%, compared with 7.59% in the control where only nutrients were added, demonstrating the application potential in enhanced oil recovery in water-flooded reservoirs, in particular, for reservoirs where IMEOR treatment cannot effectively improve oil recovery.
Vehicle Exhaust Waste Heat Recovery Model with Integrated Thermal Load Leveling

Science.gov (United States)

2015-08-01

backpressure can decrease engine power by ~1% per inch Hg.27 A specific exhaust heat exchanger design would need to take this effect into account...Materials. 2009;39:2142–2148. 4. Sprouse III C, Depcik C. Review of organic Rankine cycles for internal combustion engine exhaust waste heat recovery...Adams TG. Effect of exhaust system design on engine performance. 1980. SAE Technical Paper No. 800319. 16 1 DEFENSE TECHNICAL
Histone displacement during nucleotide excision repair

DEFF Research Database (Denmark)

Dinant, C.; Bartek, J.; Bekker-Jensen, S.

2012-01-01

Nucleotide excision repair (NER) is an important DNA repair mechanism required for cellular resistance against UV light and toxic chemicals such as those found in tobacco smoke. In living cells, NER efficiently detects and removes DNA lesions within the large nuclear macromolecular complex called...... of histone variants and histone displacement (including nucleosome sliding). Here we review current knowledge, and speculate about current unknowns, regarding those chromatin remodeling activities that physically displace histones before, during and after NER....
Using Amines and Alkanes as Thermal-Runaway Retardants for Lithium-Ion Battery

Science.gov (United States)

Shi, Yang

Thermal runaway imposes major challenges to large-scale lithium-ion batteries (LIBs). The working temperature of a LIB is usually around room temperature. However, upon mechanical abuse such as an impact or nail penetration, LIB cell components may fail and internal short circuits could be formed. As a result, a series of exothermic electrochemical reactions and decompositions would take place and the local temperature can rapidly increase. In this thesis, a few novel techniques are investigated to mitigate thermal runaway of LIBs. Mechanically triggered approach has been employed. Thermal-runaway retardant (TRR) is encapsulated in mechanically responsive packages made of materials inert to the battery environment, and upon external mechanical loadings the packages can be broken apart and release the TRR. This mechanism allows for the use of aggressive chemicals to suppress the short circuit discharge and reduce the subsequent exothermic phenomena, immediately after the battery is damaged even before temperature increase begins. The best TRR candidates are identified to be amines and alkanes. Among amines, secondary amines and tertiary amines perform better than primary amines. The reduction in electrolyte ionic conductivity and the displacement of electrolyte are the thermal-runaway-mitigation mechanisms of the secondary and the tertiary amines, respectively. Pentadecane is the best candidate among the alkanes under investigation, with the major working mechanism being electrolyte displacement. Impact tests on large pouch cells and high-energy battery chemistry were also performed; the results were quite encouraging.
Performance of thermal solvent process in Athabasca reservoir

Energy Technology Data Exchange (ETDEWEB)

Das, Swapan [Marathon Oil (Canada)

2011-07-01

In the petroleum industry, due to depletion of conventional resources and high demand operators are looking into heavy oil and bitumen production. Different recovery methods exist, some of them based on heating the reservoir and others on the use of solvent. Thermal solvent process is a combination of both: a small amount of heat is used to maintain a solvent vapor phase in the reservoir. This process has advantages, solvent is mostly recycled which increases bitumen recovery efficiency and reduces the need for fresh solvent, but it also poses challenges, such as maintaining a vapor chamber and the fact that solvent solubility might be affected by heating. The aim of this paper is to discuss these issues. Simulations and field tests were conducted on bitumen in the the Athabasca region. This paper presented a thermal solvent process and its application's results in Athabasca reservoir.
Video Games, Adolescents, and the Displacement Effect

Science.gov (United States)

Fisher, Carla Christine

2012-01-01

The displacement effect (the idea that time spent in one activity displaces time spent in other activities) was examined within the lens of adolescents' video game use and their time spent reading, doing homework, in physically active sports and activities, in creative play, and with parents and friends. Data were drawn from the Panel Study…
Livingston Parish Landfill Methane Recovery Project (Feasibility Study)

Energy Technology Data Exchange (ETDEWEB)

White, Steven

2012-11-15

economically stressed. The primary reason for this is the recent fundamental shift in the US energy landscape. Abundant supplies of natural gas have put downward pressure on any project that displaces natural gas or natural gas substitutes. Moreover, this shift appears long-term as domestic supplies for natural gas may have been increased for several hundred years. While electricity prices are less affected by natural gas prices than other thermal projects, they are still significantly affected since much of the power in the Entergy cost structure is driven by natural gas-fired generation. Consequently, rates reimbursed by the power company based on their avoided cost structure also face downward pressure over the near and intermediate term. In addition, there has been decreasing emphasis on environmental concerns regarding the production of thermal energy, and as a result both the voluntary and mandatory markets that drive green attribute prices have softened significantly over the past couple of years. Please note that energy markets are constantly changing due to fundamental supply and demand forces, as well as from external forces such as regulations and environmental concerns. At any point in the future, the outlook for energy prices may change and could deem either the electricity generation or pipeline injection project more feasible. This report is intended to serve as the primary background document for subsequent decisions made at Parish staff and governing board levels.
Toward a Heat Recovery Chimney

Directory of Open Access Journals (Sweden)

Min Pan

2011-11-01

Full Text Available The worldwide population increase and subsequent surge in energy demand leads electricity producers to increase supply in an attempt to generate larger profit margins. However, with Global Climate Change becoming a greater focus in engineering, it is critical for energy to be converted in as environmentally benign a way as possible. There are different sustainable methods to meet the energy demand. However, the focus of this research is in the area of Waste Heat Recovery. The waste heat stored in the exiting condenser cooling water is delivered to the air flow through a water-air cross flow heat exchanger. A converging thermal chimney structure is then applied to increase the velocity of the airflow. The accelerated air can be used to turn on the turbine-generator installed on the top the thermal chimney so that electricity can be generated. This system is effective in generating electricity from otherwise wasted heat.
Destabilization, Propagation, and Generation of Surfactant-Stabilized Foam during Crude Oil Displacement in Heterogeneous Model Porous Media.

Science.gov (United States)

Xiao, Siyang; Zeng, Yongchao; Vavra, Eric D; He, Peng; Puerto, Maura; Hirasaki, George J; Biswal, Sibani L

2018-01-23

Foam flooding in porous media is of increasing interest due to its numerous applications such as enhanced oil recovery, aquifer remediation, and hydraulic fracturing. However, the mechanisms of oil-foam interactions have yet to be fully understood at the pore level. Here, we present three characteristic zones identified in experiments involving the displacement of crude oil from model porous media via surfactant-stabilized foam, and we describe a series of pore-level dynamics in these zones which were not observed in experiments involving paraffin oil. In the displacement front zone, foam coalesces upon initial contact with crude oil, which is known to destabilize the liquid lamellae of the foam. Directly upstream, a transition zone occurs where surface wettability is altered from oil-wet to water-wet. After this transition takes place, a strong foam bank zone exists where foam is generated within the porous media. We visualized each zone using a microfluidic platform, and we discuss the unique physicochemical phenomena that define each zone. In our analysis, we also provide an updated mechanistic understanding of the "smart rheology" of foam which builds upon simple "phase separation" observations in the literature.
Measuring displacement signal with an accelerometer

International Nuclear Information System (INIS)

Han, Sang Bo

2010-01-01

An effective and simple way to reconstruct displacement signal from a measured acceleration signal is proposed in this paper. To reconstruct displacement signal by means of double-integrating the time domain acceleration signal, the Nyquist frequency of the digital sampling of the acceleration signal should be much higher than the highest frequency component of the signal. On the other hand, to reconstruct displacement signal by taking the inverse Fourier transform, the magnitude of the significant frequency components of the Fourier transform of the acceleration signal should be greater than the 6 dB increment line along the frequency axis. With a predetermined resolution in time and frequency domain, determined by the sampling rate to measure and record the original signal, reconstructing high-frequency signals in the time domain and reconstructing low-frequency signals in the frequency domain will produce biased errors. Furthermore, because of the DC components inevitably included in the sampling process, low-frequency components of the signals are overestimated when displacement signals are reconstructed from the Fourier transform of the acceleration signal. The proposed method utilizes curve-fitting around the significant frequency components of the Fourier transform of the acceleration signal before it is inverse-Fourier transformed. Curve-fitting around the dominant frequency components provides much better results than simply ignoring the insignificant frequency components of the signal
Overhead Transmission Lines Deicing under Different Incentive Displacement

Directory of Open Access Journals (Sweden)

Qing He

2014-01-01

Full Text Available Overhead transmission line icing is one of the main factors affecting safety and reliability of power grid. This paper proposed an excitation deicing method of iced wire and theoretically revealed the ice removal mechanism under displacement excitation conditions, by taking the LGJ-70/10 glaze icing wire as the 3D model and analyzing and studying its dynamic response under the effect of displacement excitation. The simulation results show that the stress of wire icing area is enlarged with the increase of excitation displacement and frequency. Through the comparison of the compression strength experimental results on a series of different iced wires in low temperature environment, the authors found out that the stress generated from the wire icing area is greater than the crushing strength of the ice within the scope of the calculation parameters, which proved the validity and the feasibility of the method, and finally the suitable excitation displacement is determined. Following studies show that, as far as possible, it is necessary to reduce the incentive displacement and also to select the appropriate constraint length in order to avoid the line jumping that may be caused by large span ice shedding.
Particle displacement tracking for PIV

Science.gov (United States)

Wernet, Mark P.

1990-01-01

A new Particle Imaging Velocimetry (PIV) data acquisition and analysis system, which is an order of magnitude faster than any previously proposed system has been constructed and tested. The new Particle Displacement Tracing (PDT) system is an all electronic technique employing a video camera and a large memory buffer frame-grabber board. Using a simple encoding scheme, a time sequence of single exposure images are time coded into a single image and then processed to track particle displacements and determine velocity vectors. Application of the PDT technique to a counter-rotating vortex flow produced over 1100 velocity vectors in 110 seconds when processed on an 80386 PC.

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