Sustainable colloidal-silver-impregnated ceramic filter for point-of-use water treatment.

Science.gov (United States)

Oyanedel-Craver, Vinka A; Smith, James A

2008-02-01

Cylindrical colloidal-silver-impregnated ceramic filters for household (point-of-use) water treatment were manufactured and tested for performance in the laboratory with respect to flow rate and bacteria transport. Filters were manufactured by combining clay-rich soil with water, grog (previously fired clay), and flour, pressing them into cylinders, and firing them at 900 degrees C for 8 h. The pore-size distribution of the resulting ceramic filters was quantified by mercury porosimetry. Colloidal silver was applied to filters in different quantities and ways (dipping and painting). Filters were also tested without any colloidal-silver application. Hydraulic conductivity of the filters was quantified using changing-head permeability tests. [3H]H2O water was used as a conservative tracer to quantify advection velocities and the coefficient of hydrodynamic dispersion. Escherichia coli (E. coli) was used to quantify bacterial transport through the filters. Hydraulic conductivity and pore-size distribution varied with filter composition; hydraulic conductivities were on the order of 10(-5) cm/s and more than 50% of the pores for each filter had diameters ranging from 0.02 to 15 microm. The filters removed between 97.8% and 100% of the applied bacteria; colloidal-silver treatments improved filter performance, presumably by deactivation of bacteria. The quantity of colloidal silver applied per filter was more important to bacteria removal than the method of application. Silver concentrations in effluent filter water were initially greater than 0.1 mg/L, but dropped below this value after 200 min of continuous operation. These results indicate that colloidal-silver-impregnated ceramic filters, which can be made using primarily local materials and labor, show promise as an effective and sustainable point-of-use water treatment technology for the world's poorest communities.

The Novel Design and Manufacturing Technology of Densified RDF from Reclaimed Landfill without a Mixing Binding Agent Using a Hydraulic Hot Pressing Machine

Directory of Open Access Journals (Sweden)

Kerdsuwan Somrat

2016-01-01

Full Text Available The manufacturing of RDF (Refuse Derived Fuel from a conventional cold press extrusion machine is not suitable for producing RDF from reclaimed landfill since it is not identical in shape and form after production due to the swelling of the plastic fraction contained inside the reclaimed landfill and hence needs a very high compression force. Moreover, a binder agent is needed in order to keep the RDF in a similar shape and form. A novel design and manufacturing technology for a hydraulic hot pressing machine has been established and can produce high-quality RDF without any binder. The two electrical heaters are installed at the inner core and on the surface of the mold. The compression force on the mold is performed by a hydraulic jack. In addition, a newly-designed locking plate system which is designed by a slider to open and close along the paired horizontal slots, can reduce the cycle time of the manufacturing process and yield higher productivity. The testing properties of the RDF produced by the novel hydraulic hot pressing machine include the examination of size, shape, weight, unit density, bulk density, compression strength, moisture content, and heating value. The results showed that the RDF is suitable to be used as feedstock in an incinerator or gasifier to produce green and clean energy from reclaimed landfill.

THERMAL HYDRAULIC ISSUES OF CONTAINMENT FILTERED VENTING SYSTEM FOR A LONG OPERATING TIME

Directory of Open Access Journals (Sweden)

YOUNG SU NA

2014-12-01

Full Text Available This study investigated the thermal hydraulic issues in the Containment Filtered Venting System (CFVS for a long operating time using the MELCOR computer code. The modeling of the CFVS, including the models for pool scrubbing and the filter, was added to the input file for the OPR-1000, and a Station Blackout (SBO was chosen as an accident scenario. Although depressurization in the containment building as a primary objective of the CFVS was successful, the decontamination feature by scrubbing and filtering in the CFVS for a long operating time could fail by the continuous evaporation of the scrubbing solution. After the operation of the CFVS, the atmosphere temperature in the CFVS became slightly above the water saturation temperature owing to the release of an amount of steam with high temperature from the containment building to the scrubbing solution. Reduced pipe diameters at the inlet and outlet of the CFVS vessel mitigated the evaporation of scrubbing water by controlling the amount of high-temperature steam and the water saturation temperature.

Laboratory for filter testing

Energy Technology Data Exchange (ETDEWEB)

Paluch, W.

1987-07-01

Filters used for mine draining in brown coal surface mines are tested by the Mine Draining Department of Poltegor. Laboratory tests of new types of filters developed by Poltegor are analyzed. Two types of tests are used: tests of scale filter models and tests of experimental units of new filters. Design and operation of the test stands used for testing mechanical properties and hydraulic properties of filters for coal mines are described: dimensions, pressure fluctuations, hydraulic equipment. Examples of testing large-diameter filters for brown coal mines are discussed.

Mannes of Forging and Perspectives of Knuckle Joint Presses Modernization

Directory of Open Access Journals (Sweden)

A. A. Antsifirov

2014-01-01

Full Text Available The article raises an issue to enhance technological forging capabilities on the known knuckle joint presses. It provides an illustrated overview of main design types of presses with crank-knuckle, toggle-knuckle, and knuckle joint mechanisms. The article also shows the advantages of the modernization way and improvement just of the active press equipment in terms of quality-to-price ratio, for example, as compared to the similar new foreign press equipment.It gives an overview of features, which provide forging processes owing to kinetic energy accumulated with the moving parts of the known designs of the knuckle joint presses depending on the drive actuating mechanism. Focused attention is drawn to forging on the knuckle joint presses for a time of contact with a work piece to be comparable with the duration of the work piece deformation process on hydraulic forging hammers. This allows us to forge thin-wall products with process automation compared to the forging hammers.Analysis of accumulating processes of kinetic energy by the moving parts of the knuckle joint presses has shown that presses driven by hydraulic cylinders or two screw hydraulic cylinder are the most optimal for technological operations as evidenced by references to domestic and foreign invention certificates and patents. The article presents disadvantages of forging on presses with hydraulic or pneumatic drive. It is a dependence of the deformation force, caused, mainly, by a force of the drive cylinder. The article gives linear movement rate quantities of press moving members depending on the drives of the actuating mechanism. Based on the above analysis of the features to manufacture work pieces on the knuckle joint presses, the article gives the rationale for the relevance of forging in a short period of time, provided that the moving parts of the press accumulate the required kinetic energy. This can be achieved only through modernization and improvement of forging

Removal of chloride from fly ash produced in hazardous waste incineration by leaching and displacement washing in a vertical filter press.

Science.gov (United States)

Kinnarinen, Teemu; Huhtanen, Mikko; Penttilä, Mika; Häkkinen, Antti

2013-02-01

Fly ash is generated in large quantities by waste incineration processes. Chloride is commonly present in the fly ash produced by the incineration of hazardous materials, such as polyvinylchloride plastic. Major difficulties related to the disposal and handling of fly ash include the high concentration of easily leachable chlorides, heavy metals and toxic compounds. In order to avoid adverse environmental effects from the disposal of fly ash, the content of soluble chlorides must be reduced. One of the most effective options for chloride removal is leaching and displacement washing in a filter press. The primary aim of this study was to obtain efficient removal of chloride from fly ash by utilizing a leaching and displacement washing process, carried out in a filter press. The secondary objective was to obtain high filtration capacities and low filter cake moisture contents. The slurry was prepared by mixing fly ash with water at an ash:water ratio of 1:2 and filtered to separate the solids from the liquid. After solid-liquid separation, most of the dissolved residual chloride was removed from the filter cake by washing the cake with fresh water in the second stage of separation. It was possible to remove up to 98% of the total chloride and to obtain sufficient filtration capacities. The residual moisture content of the filter cakes varied from 22 to 35 wt%, which meant that the cakes could be disposed of in landfill, or possibly utilized as a construction material.

Computational fluid dynamics simulations of single-phase flow in a filter-press flow reactor having a stack of three cells

International Nuclear Information System (INIS)

Sandoval, Miguel A.; Fuentes, Rosalba; Walsh, Frank C.; Nava, José L.; Ponce de León, Carlos

2016-01-01

Highlights: • Computational fluid dynamic simulations in a filter-press stack of three cells. • The fluid velocity was different in each cell due to local turbulence. • The upper cell link pipe of the filter press cell acts as a fluid mixer. • The fluid behaviour tends towards a continuous mixing flow pattern. • Close agreement between simulations and experimental data was achieved. - Abstract: Computational fluid dynamics (CFD) simulations were carried out for single-phase flow in a pre-pilot filter press flow reactor with a stack of three cells. Velocity profiles and streamlines were obtained by solving the Reynolds-Averaged Navier-Stokes (RANS) equations with a standard k − ε turbulence model. The flow behaviour shows the appearance of jet flow at the entrance to each cell. At lengths from 12 to 15 cm along the cells channels, a plug flow pattern is developed at all mean linear flow rates studied here, 1.2 ≤ u ≤ 2.1 cm s −1 . The magnitude of the velocity profiles in each cell was different, due to the turbulence generated by the change of flow direction in the last fluid manifold. Residence time distribution (RTD) simulations indicated that the fluid behaviour tends towards a continuous mixing flow pattern, owing to flow at the output of each cell across the upper cell link pipe, which acts as a mixer. Close agreement between simulations and experimental RTD was obtained.

Nitrogen removal in permeable woodchips filters affected by hydraulic loading rate and woodchips ratio

DEFF Research Database (Denmark)

Bruun, Jacob Druedahl; Kjærgaard, Charlotte; Hoffmann, Carl Christian

2016-01-01

response of mixed reactive media (woodchips-Seashells and woodchips-Filtralite mixtures) at two woodchips ratios (WR) to changes in the hydraulic loading rate (HLR). The tests implied continuous loading of aerated NO3-N spiked artificial drainage water and tritium (3H2O) breakthrough experiments. Flow...... normalized nitrate reduction rates were 0.35-3.97 g N m-3 L-1, corresponding to N- removal efficiencies of 5 to 74% depending on HLR and filter mixtures. At high HLR oxic conditions prevailed, thus N removal was restricted to the immobile domain, controlled by diffusion. At lower HLR, progressively lower...

Geo synthetics in hydraulic and coastal engineering: Filters, revetments and sand filled structures

International Nuclear Information System (INIS)

Bezuijen, A.; Pilarczyk, K. W.

2014-01-01

The paper deals with 2 applications of geo textiles in coastal and hydraulic engineering: Geo textiles in filters and revetments; and geo textiles in sand filled structure. Geo textiles are often replacing granular filters. However, they have different properties than a granular filter. For the application of geo textiles in revetments, the consequences of the different properties will be shown: how permeability is influenced by a geo textile and what can be the consequences of the weight differences between granular and geo textile filters. In the other application, the filter properties of geo textiles are only secondary. In geo textile tubes and containers the geo textile is used as wrapping material to create large unties that will not erode during wave attach. the structures with geo textile tubes and containers serve as an alternative for rock based structures. The first of these structures were more or less constructed by trial and error, but research on the shape of the structures, the stability under wave attach and the durability of the used of the used material has given the possibility to use design tools for these structures. Recently also the morphological aspects of these structures have been investigated. This is of importance because regularly structures with geo textile tubes fail due to insufficient toe protection against the scour hole that that develops in front of the structure, leading to undermining of the structure. Recent research in the Dealt Flume of Deltares and the Large Wave Flume in Hannover has led to better understanding what mechanisms determine the stability under wave attach. It is shown that also the degree of filling is of importance and the position of the water level with respect to the tube has a large influence. (Author)

Simulation of the hydraulic performance of highway filter drains through laboratory models and stormwater management tools.

Science.gov (United States)

Sañudo-Fontaneda, Luis A; Jato-Espino, Daniel; Lashford, Craig; Coupe, Stephen J

2017-05-23

Road drainage is one of the most relevant assets in transport infrastructure due to its inherent influence on traffic management and road safety. Highway filter drains (HFDs), also known as "French Drains", are the main drainage system currently in use in the UK, throughout 7000 km of its strategic road network. Despite being a widespread technique across the whole country, little research has been completed on their design considerations and their subsequent impact on their hydraulic performance, representing a gap in the field. Laboratory experiments have been proven to be a reliable indicator for the simulation of the hydraulic performance of stormwater best management practices (BMPs). In addition to this, stormwater management tools (SMT) have been preferentially chosen as a design tool for BMPs by practitioners from all over the world. In this context, this research aims to investigate the hydraulic performance of HFDs by comparing the results from laboratory simulation and two widely used SMT such as the US EPA's stormwater management model (SWMM) and MicroDrainage®. Statistical analyses were applied to a series of rainfall scenarios simulated, showing a high level of accuracy between the results obtained in laboratory and using SMT as indicated by the high and low values of the Nash-Sutcliffe and R 2 coefficients and root-mean-square error (RMSE) reached, which validated the usefulness of SMT to determine the hydraulic performance of HFDs.

Peatlands as Filters for Polluted Mine Water?—A Case Study from an Uranium-Contaminated Karst System in South Africa—Part III: Quantifying the Hydraulic Filter Component

Directory of Open Access Journals (Sweden)

Frank Winde

2011-03-01

Full Text Available As Part III of a four-part series on the filter function of peat for uranium (U, this paper focuses on the hydraulic component of a conceptual filter model introduced in Part II. This includes the quantification of water flow through the wetland as a whole, which was largely unknown and found to be significantly higher that anticipated. Apart from subaquatic artesian springs associated with the underlying karst aquifer the higher flow volumes were also caused by plumes of polluted groundwater moving laterally into the wetland. Real-time, quasi-continuous in situ measurements of porewater in peat and non-peat sediments indicate that rising stream levels (e.g., during flood conditions lead to the infiltration of stream water into adjacent peat deposits and thus allow for a certain proportion of flood water to be filtered. However, changes in porewater quality triggered by spring rains may promote the remobilization of possibly sorbed U.

Pemanfaatan Silika Abu Sekam Padi sebagai Bahan Pengisi Rubber Membrane Filter Press untuk Memisahkan Minyak Inti Sawit

OpenAIRE

Nasruddin

2012-01-01

This research was aimed to obtain rubber membrane filter press (RMFP) from natural rubber (NR) as well as synthetic rubber (chloroprene rubber and nytrike butadiene rubber). The research method was done my vulcanizing natural rubber, synthetic rubber, and filler to shape RMFP. Research formulation was done with 8 units of experiments using variations of mixers that have been pre-determined. The examination to the RMFP was done with ASTM test methods that cover parameters such as viscometer mo...

Simultaneous identification of a contaminant source and hydraulic conductivity via the restart normal-score ensemble Kalman filter

Science.gov (United States)

Xu, Teng; Gómez-Hernández, J. Jaime

2018-02-01

Detecting where and when a contaminant entered an aquifer from observations downgradient of the source is a difficult task; this identification becomes more challenging when the uncertainty about the spatial distribution of hydraulic conductivity is accounted for. In this paper, we have implemented an application of the restart normal-score ensemble Kalman filter (NS-EnKF) for the simultaneous identification of a contaminant source and the spatially variable hydraulic conductivity in an aquifer. The method is capable of providing estimates of the spatial location, initial release time, the duration of the release and the mass load of a point-contamination event, plus the spatial distribution of hydraulic conductivity together with an assessment of the estimation uncertainty of all the parameters. The method has been applied in synthetic aquifers exhibiting both Gaussian and non-Gaussian patterns. The identification is made possible by assimilating in time both piezometric head and concentration observations from an array of observation wells. The method is demonstrated in three different synthetic scenarios that combine hydraulic conductivities with unimodal and bimodal histograms, and releases in high and low conductivity zones. The results prove that the specific implementation of the EnKF is capable of recovering the source parameters with some uncertainty and of recovering the main patterns of heterogeneity of the hydraulic conductivity fields by assimilating a sufficient number of state variable observations. The proposed approach is an important step towards contaminant source identification in real aquifers, which may have logconductivity spatial distributions with either Gaussian or non-Gaussian features, yet, it is still far from practical applications since the transport parameters, the external sinks and sources and the initial and boundary conditions are assumed known.

Effect of physical property of supporting media and variable hydraulic loading on hydraulic characteristics of advanced onsite wastewater treatment system.

Science.gov (United States)

Sharma, Meena Kumari; Kazmi, Absar Ahmad

2015-01-01

A laboratory-scale study was carried out to investigate the effects of physical properties of the supporting media and variable hydraulic shock loads on the hydraulic characteristics of an advanced onsite wastewater treatment system. The system consisted of two upflow anaerobic reactors (a septic tank and an anaerobic filter) accommodated within a single unit. The study was divided into three phases on the basis of three different supporting media (Aqwise carriers, corrugated ring and baked clay) used in the anaerobic filter. Hydraulic loadings were based on peak flow factor (PFF), varying from one to six, to simulate the actual conditions during onsite wastewater treatment. Hydraulic characteristics of the system were identified on the basis of residence time distribution analyses. The system showed a very good hydraulic efficiency, between 0.86 and 0.93, with the media of highest porosity at the hydraulic loading of PFF≤4. At the higher hydraulic loading of PFF 6 also, an appreciable hydraulic efficiency of 0.74 was observed. The system also showed good chemical oxygen demand and total suspended solids removal efficiency of 80.5% and 82.3%, respectively at the higher hydraulic loading of PFF 6. Plug-flow dispersion model was found to be the most appropriate one to describe the mixing pattern of the system, with different supporting media at variable loading, during the tracer study.

SENSORS FAULT DIAGNOSIS ALGORITHM DESIGN OF A HYDRAULIC SYSTEM

Directory of Open Access Journals (Sweden)

Matej ORAVEC

2017-06-01

Full Text Available This article presents the sensors fault diagnosis system design for the hydraulic system, which is based on the group of the three fault estimation filters. These filters are used for estimation of the system states and sensors fault magnitude. Also, this article briefly stated the hydraulic system state control design with integrator, which is important assumption for the fault diagnosis system design. The sensors fault diagnosis system is implemented into the Matlab/Simulink environment and it is verified using the controlled hydraulic system simulation model. Verification of the designed fault diagnosis system is realized by series of experiments, which simulates sensors faults. The results of the experiments are briefly presented in the last part of this article.

Effects of substrate concentration, specific surface area and hydraulic loading on the treatment efficiency in a submerged biological filter. Sesshoku bakkiho no shori koritsu ni taisuru kishitsu nodo, hihyo menseki oyobi suiryo fuka no eikyo

Energy Technology Data Exchange (ETDEWEB)

Iyo, T; Ono, S; Yoshino, T [Kitasato University, Kanagawa (Japan). School of Hygienic Science

1991-06-10

Effects of substrate concentration, specific surface area, and hydraulic loading, which are major factors influencing treatment efficiency in a submerged biological filter, were analyzed through the test with a special apparatus. In the test, the wall of the submerged biological filter was regarded as the contact material, and the specific surface area was changed by adjusting the sectional form of the filter. Using specimens from actual plant reservoirs, treatment efficiency for each case of three kinds of substrate concentration and hydraulic loading was measured. BOD removal rate was lower with smaller specific surface area. It was conspicuous particularly with higher BOD concentration in influent water. After the multiple regression analysis of the test results, the multiple regression equation to estimate BOD residual rate from three variates such as BOD concentration, specific surface area, and hydraulic loading was obtained. When 200mg l as BOD concentration and 50m{sup 2} m{sup {minus}3} as specific surface area were applied in this equation, the result almost agreed with the tendency obtained from data of actual plants. 6 refs., 4 figs., 1 tab.

Tracking control of the hydraulically actuated flexible manipulator

International Nuclear Information System (INIS)

Kwon, D.S.; Babcock, S.M.; Burks, B.L.; Kress, R.L.

1995-01-01

The remediation of single-shell radioactive waste storage tanks is one of the urgent tasks of the Department of Energy that challenge state-of-the-art equipment and methods. The use of long-reach manipulators is being seriously considered for this remediation task. Because high payload capacity and high length-to-cross-section ratio requirements, these long-reach manipulator systems are expected to use hydraulic actuators and to exhibit significant structural flexibility. The controller has been designed to compensate for the hydraulic actuator dynamics by using a load-compensated velocity feedforward loop and to increase the bandwidth by using a pressure feed backloop. Shaping filter techniques have been applied as a feedforward controller to avoid structural vibrations during operation. Among various types of shaping filter methods investigated an approach, referred to as a ''feedforward simulation filter'' that uses embedded simulation, has been presented

A method to press powder at 6000 ton using small amount of explosive

Science.gov (United States)

Hilmi, Ahmad Humaizi; Azmi, Nor Azmaliana; Ismail, Ariffin

2017-12-01

Large die hydraulic press forces are one of the key instruments in making jumbo planes. The machine can produce aircraft components such as wing spars, landing gear supports and armor plates. Superpower nations such as USA, Russia, Germany, Japan, Korea and China have large die hydraulic press which can press 50,000 tons. In Malaysia, heavy-duty press is available from companies such as Proton that builds chassis for cars. However, that heavy-duty press is not able to produce better bulkhead for engines, fuselage, and wings of an aircraft. This paper presents the design of an apparatus that uses 50 grams of commercial grade explosives to produce 6000 tons of compaction. This is a first step towards producing larger scale apparatus that can produce 50,000-ton press. The design was done using AUTODYN blast simulation software. According to the results, the maximum load the apparatus can withstand was 6000 tons which was contributed by 50 grams of commercial explosive(Emulex). Explosive size larger than 50 grams will lead to catastrophic failure. Fabrication of the apparatus was completed. However, testing of the apparatus is not presented in this article.

Performance and optimisation of trickling filters on eel farms

NARCIS (Netherlands)

Kamstra, A.; Heul, van der J.W.; Nijhof, M.

1998-01-01

The design of trickling filters used on commercial eel farms differs considerably with respect to dimensions, hydraulic and substrate loads and filter medium applied. In this paper, a model, developed for ammonium removal in a pilot-scale trickling filter, has been validated for a range of

Real-time neural network-based self-tuning control of a nonlinear electro-hydraulic servomotor

Energy Technology Data Exchange (ETDEWEB)

Canelon, J.I.; Ortega, A.G. [Univ. del Zulia, Maracaibo, Zulia (Venezuela, Bolivarian Republic of). School of Electrical Engineering; Shieh, L.S. [Houston Univ., Houston, TX (United States). Dept. of Electrical and Computer Engineering; Bastidas, J.I. [Univ. del Zulia, Maracaibo, Zulia (Venezuela, Bolivarian Republic of). School of Mechanical Engineering; Zhang, Y.; Akujuobi, C.M. [Prairie View A and M Univ., Prairie View, TX (United States). Center of Excellence for Communication Systems Technology Research and Dept. of Engineering Technology

2010-08-13

For high power applications, hydraulic actuators offer many advantages over electromagnetic actuators, including higher torque/mass ratios; smaller control gains; excellent torque capability; filtered high frequency noise; better heat transfer characteristics; smaller size; higher speed of response of the servomechanism; cheaper hardware; and higher reliability. Therefore, any application that requires a large force applied smoothly by an actuator is a candidate for hydraulic power. Examples of such applications include vehicle steering and braking systems; roll mills; drilling rigs; heavy duty crane and presses; and industrial robots and actuators for aircraft control surfaces such as ailerons and flaps. It is extremely important to create effective control strategies for hydraulic systems. This paper outlined the real-time implementation of a neural network-based approach, for self-tuning control of the angular position of a nonlinear electro-hydraulic servomotor. Using an online training algorithm, a neural network autoregressive moving-average model with exogenous input (ARMAX) model of the system was identified and continuously updated and an optimal linear ARMAX model was determined. The paper briefly depicted the neural network-based self-tuning control approach and a description of the experimental equipment (hardware and software) was presented including the implementation details. The experimental results were discussed and conclusions were summarized. It was found that the approach proved to be very effective in the control of this fast dynamics system, outperforming a fine tuned PI controller. Therefore, although the self-tuning approach was computationally demanding, it was feasible for real-time implementation. 22 refs., 6 figs.

Hydraulic regenerative system for a light vehicle

OpenAIRE

Orpella Aceret, Jordi; Guinart Trayter, Xavier

2009-01-01

The thesis is based in a constructed light vehicle that must be improved by adding a hydraulic energy recovery system. This vehicle named as TrecoLiTH, participated in the Formula Electric and Hybrid competition (Formula EHI) 2009 in Italy -Rome- and won several awards. This system consists in two hydraulic motors hub mounted which are used to store fluid at high pressure in an accumulator when braking. Through a valve the pressure will flow from the high pressure accumulator to the low press...

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

Thermal-hydraulic effects of transition to improved System 80TM fuel

International Nuclear Information System (INIS)

Rodack, T.; Joffre, P.F.; Kapoor, R.K.

2004-01-01

ABB CE's improved System 80 TM PWR fuel design includes GUARDIAN debris-resistant features and laser-welded Zircaloy grids. The GUARDIAN features include an Inconel grid with debris-filtering features located just above the Lower End Fitting, and a solid fuel rod bottom end cap that extends above the filtering features. Tests and analyses were done to establish the impact of these design improvements on fuel assembly hydraulic performance. Further analysis was done to determine the mixed core thermal-hydraulic performance as the transition is made over two fuel cycles to a full core of the improved System 80 TM fuel. Results confirm that the Thermal-Hydraulic (T-H) effects of the reduction in hydraulic resistance between the improved and resident fuel due to the laser-welded Zircaloy grids offsets the effects of the increased resistance GUARDIAN grid. Therefore, the mechanically improved System 80 TM fuel can be implemented with no net impact on Departure from Nucleate Boiling (DNB) margin in transition cores. (author)

Anaerobic treatment of rice winery wastewater in an upflow filter packed with steel slag under different hydraulic loading conditions.

Science.gov (United States)

Jo, Yeadam; Kim, Jaai; Hwang, Seokhwan; Lee, Changsoo

2015-10-01

Rice-washing drainage (RWD), a strong organic wastewater, was anaerobically treated using an upflow filter filled with blast-furnace slag. The continuous performance of the reactor was examined at varying hydraulic retention times (HRTs). The reactor achieved 91.7% chemical oxygen demand removal (CODr) for a 10-day HRT (0.6 g COD/Ld organic loading rate) and maintained fairly stable performance until the HRT was shortened to 2.2 days (CODr > 84%). Further decreases in HRT caused process deterioration (CODr < 50% and pH < 5.5 for a 0.7-day HRT). The methane production rate increased with decreasing HRT to reach the peak level for a 1.3-day HRT, whereas the yield was significantly greater for 3.4-day or longer HRTs. The substrate removal and methane production kinetics were successfully evaluated, and the generated kinetic models produced good performance predictions. The methanogenic activity of the reactor likely relies on the filter biofilm, with Methanosaeta being the main driver. Copyright © 2015 Elsevier Ltd. All rights reserved.

Selective perceptions of hydraulic fracturing.

Science.gov (United States)

Sarge, Melanie A; VanDyke, Matthew S; King, Andy J; White, Shawna R

2015-01-01

Hydraulic fracturing (HF) is a focal topic in discussions about domestic energy production, yet the American public is largely unfamiliar and undecided about the practice. This study sheds light on how individuals may come to understand hydraulic fracturing as this unconventional production technology becomes more prominent in the United States. For the study, a thorough search of HF photographs was performed, and a systematic evaluation of 40 images using an online experimental design involving N = 250 participants was conducted. Key indicators of hydraulic fracturing support and beliefs were identified. Participants showed diversity in their support for the practice, with 47 percent expressing low support, 22 percent high support, and 31 percent undecided. Support for HF was positively associated with beliefs that hydraulic fracturing is primarily an economic issue and negatively associated with beliefs that it is an environmental issue. Level of support was also investigated as a perceptual filter that facilitates biased issue perceptions and affective evaluations of economic benefit and environmental cost frames presented in visual content of hydraulic fracturing. Results suggested an interactive relationship between visual framing and level of support, pointing to a substantial barrier to common understanding about the issue that strategic communicators should consider.

Thermal Hydraulic Analysis on Containment Filtered Venting System

Energy Technology Data Exchange (ETDEWEB)

Bang, Young Suk; Park, Tong Kyu; Lee, Doo Yong; Lee, Byung Chul [FNC Technology Co. Ltd., Yongin (Korea, Republic of); Lee, Sang Won; Kim, Hyeong Taek [KHNP-Central Research Institute, Daejeon (Korea, Republic of)

2014-05-15

In this study, the thermal hydraulic conditions (e. g. pressure and flow rate) at each component have been examined and the sensitivity analysis on CFVS design parameters (e. g. water inventory, volumetric flow rate). The purpose is to know the possible range of flow conditions at each component to determine the optimum size of filtration system. GOTHIC code has been used to simulate the thermal-hydraulic behavior inside of CFVS. The behavior of flows in the CFVS has been investigated. The vessel water level and the flow rates during the CFVS operation are examined. It was observed that the vessel water level would be changed significantly due to steam condensation/thermal expansion and steam evaporation. Therefore, the vessel size and the initial water inventory should be carefully determined to keep the minimum water level required for filtration components and not to flood the components in the upper side of the vessel. It has been also observed that the volumetric flow rate is maintained during the CFVS operation, which is beneficial for pool scrubbing units. However, regarding the significant variations at the orifice downstream, careful design would be necessary.

Particulate removal processes and hydraulics of porous gravel media filters

Science.gov (United States)

Minto, J. M.; Phoenix, V. R.; Dorea, C. C.; Haynes, H.; Sloan, W. T.

2013-12-01

Sustainable urban Drainage Systems (SuDS) are rapidly gaining acceptance as a low-cost tool for treating urban runoff pollutants close to source. Road runoff water in particular requires treatment due to the presence of high levels of suspended particles and heavy metals adsorbed to these particles. The aim of this research is to elucidate the particle removal processes that occur within gravel filters that have so far been considered as 'black-box' systems. Based on these findings, a better understanding will be attained on what influences gravel filter removal efficiency and how this changes throughout their design life; leading to a more rational design of this useful technology. This has been achieved by tying together three disparate research elements: tracer residence time distribution curves of filters during clogging; 3D magnetic resonance imaging (MRI) of clogging filters and computational fluid dynamics (CFD) modelling of complex filter pore networks. This research relates column average changes in particle removal efficiency and tracer residence time distributions (RTDs) due to clogging with non-invasive measurement of the spatial variability in particle deposition. The CFD modelling provides a link between observed deposition patterns, flow velocities and wall shear stresses as well as the explanations for the change in RTD with clogging and the effect on particle transport. Results show that, as a filter clogs, particles take a longer, more tortuous path through the filter. This is offset by a reduction in filter volume resulting in higher flow velocities and more rapid particle transport. Higher velocities result in higher shear stresses and the development of preferential pathways in which the velocity exceeds the deposition threshold and the overall efficiency of the filter decreases. Initial pore geometry is linked to the pattern of deposition and subsequent formation of preferential pathways. These results shed light on the 'black-box' internal

Using mathematical modelling of the changes in the characteristics of the bodies during SHS-process for porous ceramic filters manufacture

Directory of Open Access Journals (Sweden)

Юлія Славоміровна Повстяна

2016-11-01

Full Text Available Porous ceramic materials possess great lifetime, high mechanical strength, are resistant to household effects and easy to use. The binder volume fraction and normalized pressure as a function of the temperature in the SHS process in the ceramic body have been studied in this work. Basing on theoretical calculations the temperature range of the binder burnout has been determined. The theoretical results can be used to predict and obtain porous ceramic filters with predetermined characteristics. The theoretical calculations were used in the manufacture of experimental samples of porous ceramic bodies obtained on the basis of 18H2N4MA steel scale and the saponite. Pressing in a hydraulic press was used to manufacture ceramic pieces. Unilateral press mould made of stainless steel was used to form the samples. Pressing was carried out in the pressure range of 10-25 MPa. The resulting pieces were formed in cylinders of 30mm in diameter and 40 mm height. Sintering of the samples was conducted in the modernized reactor for the SHS process. Mathematical justification of SHS process made it possible to avoid the formation of cracks in the ceramic bodies and crumble areas

Adaptive Control System of Hydraulic Pressure Based on The Mathematical Modeling

Science.gov (United States)

Pilipenko, A. V.; Pilipenko, A. P.; Kanatnikov, N. V.

2016-04-01

In this paper, the authors highlight the problem of replacing an old heavy industrial equipment, and offer the replacement of obsolete control systems on the modern adaptive control system, which takes into account changes in the hydraulic system of the press and compensates them with a corrective action. The proposed system can reduce a water hammer and thereby increase the durability of the hydraulic system and tools.

Tertiary treatment of textile wastewater with combined media biological aerated filter (CMBAF) at different hydraulic loadings and dissolved oxygen concentrations

International Nuclear Information System (INIS)

Liu Fang; Zhao Chaocheng; Zhao Dongfeng; Liu Guohua

2008-01-01

An up-flow biological aerated filter packed with two layers media was employed for tertiary treatment of textile wastewater secondary effluent. Under steady state conditions, good performance of the reactor was achieved and the average COD, NH 4 + -N and total nitrogen (TN) in the effluent were 31, 2 and 8 mg/L, respectively. For a fixed dissolved oxygen (DO) concentration, an increase of hydraulic loading resulted in a decrease in substrate removal. With the increase of hydraulic loadings from 0.13 to 0.78 m 3 /(m 2 h), the removal efficiencies of COD, NH 4 + -N and TN all decreased, which dropped from 52 to 38%, from 90 to 68% and from 45 to 33%, respectively. In addition, the results also confirmed that the increase of COD and NH 4 + -N removal efficiencies resulted from the increase of DO concentrations, but this variation trend was not observed for TN removal. With the increase of DO concentrations from 2.4 to 6.1 mg/L, the removal efficiencies of COD and NH 4 + -N were 39-53% and 64-88%, whenas TN removal efficiencies increased from 39 to 42% and then dropped to 35%

Hydraulic fracture considerations in oil sand overburden dams

Energy Technology Data Exchange (ETDEWEB)

Cameron, R.; Madden, B.; Danku, M. [Syncrude Canada Ltd., Fort McMurray, AB (Canada)

2008-07-01

This paper discussed hydraulic fracture potential in the dry-filled temporary dams used in the oil sands industry. Hydraulic fractures can occur when reservoir fluid pressures are greater than the minimum stresses in a dam. Stress and strain conditions are influenced by pore pressures, levels of compaction in adjacent fills as well as by underlying pit floor and abutment conditions. Propagation pressure and crack initiation pressures must also be considered in order to provide improved hydraulic fracture protection to dams. Hydraulic fractures typically result in piping failures. Three cases of hydraulic fracture at oil sands operations in Alberta were presented. The study showed that hydraulic fracture failure modes must be considered in dam designs, particularly when thin compacted lift of dry fill are used to replace wetted clay cores. The risk of hydraulic fractures can be reduced by eliminating in situ bedrock irregularities and abutments. Overpressure heights, abutment sloping, and the sloping of fills above abutments, as well as the dam's width and base conditions must also be considered in relation to potential hydraulic fractures. It was concluded that upstream sand beaches and internal filters can help to prevent hydraulic fractures in dams in compacted control zones. 5 refs., 16 figs.

Preliminary investigation into the pressing process of sweet pearl millet and sweet sorghum biomass for ethanol production

Energy Technology Data Exchange (ETDEWEB)

Crepeau, M.; Khelifi, M.; Vanasse, A. [Laval Univ., Quebec City, PQ (Canada). Dept. of Soil Science and Agri-Food Engineering

2010-07-01

Corn is the main source for biofuel production in North America. However, both sweet pearl millet and sweet sorghum crops represent an interesting alternative to corn for ethanol production because of their high biomass yield under a wide range of environmental conditions and high concentration of readily fermentable sugars. Coproducts such as pressing residues can be also be utilized so that nothing is lost in the process. However, in order to improve the extraction of juice for ethanol production, the pressing process of this biomass must be optimized. Preliminary experiments were therefore conducted to optimize the juice extraction from sweet pearl millet and sweet sorghum using 2 different presses, notably a screw press and a manually operated hydraulic press. Both types of biomass were either chopped finely or coarsely and were exposed to various pressures with the hydraulic press. The volume of juice extracted from both crops increased linearly with increasing pressure. Sweet sorghum appeared to be a better feedstock for ethanol production because it produced about 0.03 to 0.06 litre of juice per kg of biomass more than sweet pearl millet. Juice extraction was more effective with the screw press, but only a small difference was noted between the 2 chopping modes.

Development test of multiple die with hydraulic compensation and auto lubrication

International Nuclear Information System (INIS)

Chen Mengyou; Zhang Xichang; Zhu Ninghua; Liu Zichang

1988-05-01

Multiple die with hydraulic compensating device adopts the design of multidies gathering in a common grease cavity, using high temperature lubricating grease as the pressure compensating medium. According to Pascal's Law, each die will receive equal pressure during the process of pressing. Such device changes the equi-volume pressing mode of single mechanical die to equipressure pressing mode of multiple die in nuclear fuel element production, thus improves the quality and raises the quantity of nuclear fuel and powder ceramic products, giving a better economic benefit

TA-03-0035 Press Building – D&D

Energy Technology Data Exchange (ETDEWEB)

Hasenack, Marvin Leroy [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-11-02

The Press Building was constructed in 1954 with 15,073 ft² of floor space. It was built to house a 5000 ton double action Lake Erie hydraulic press and a uranium casting area. Missions included uranium activities associated with the Nuclear Weapons and Rover Rocket programs. At the end of the Rover program, the building continued to support various uranium materials science projects until the building was placed into a cold and dark status in 2013 and then was demolished in 2017. The building interior, the press, and associated systems were radiological contaminated and disposed of as low level waste. The demolition of this building opened up valuable real estate in the TA-3 area for the future construction of an ~11,000 Sq. Ft. Biosafety Level 2 laboratory and office building. This building will support the ongoing Bioscience Division mission at the laboratory.

Linking plant hydraulics and beta diversity in tropical forests

Energy Technology Data Exchange (ETDEWEB)

Christoffersen, Bradley [Earth and Environmental Sciences, Los Alamos National Laboratory, Los Alamos NM 87545 USA; Meir, Patrick [School of GeoSciences, University of Edinburgh, Edinburgh EH9 3FE UK; Research School of Biology, Australian National University, Canberra ACT 2601 Australia; McDowell, Nate G. [Pacific Northwest National Laboratory, Richland WA 99352 USA

2017-05-31

In tropical forests, studies of xylem traits governing water transport through plants, or ‘hydraulic architecture’ (Tyree et al., 1991), and changes in species composition across environmental gradients, or ‘beta diversity’ (Gentry, 1988; Ackerly & Cornwell, 2007), have progressedmostly in parallel until recently (Hao et al., 2008; Bartlett et al., 2016). In this issue of New Phytologist, Cosme et al. (pp. 000–5 000) present a timely contribution to the intersection of plant hydraulic architecture (HA) with trait-based community ecology. Building on previous biogeographical work that demonstrated shifts in species composition (beta diversity) across a gradient from valleys to plateaus in central Amazonia (Schietti et al., 2014), Cosme et al. explore how variation in HA might underpin this sorting, sampling pairs of congeneric species restrictedmostly to either plateau or valley habitats. Valley species had significantly lower wood density and higher hydraulically-weighted vessel diameter and vessel area. By contrast, trees with some of the largest hydraulically-weighted vessel diameters existed in tall, deciduous plateau species, while the leaf: sapwood area ratio decreased with height in valley but not plateau species. These intriguing results suggest that species differentiation in water transport traits mediate edaphic filtering along the valley-toplateau gradient, in contrast to previous work where wood mechanical support mediated valley-to-plateau environmental filtering (Fortunel et al., 2014).

Study of long term chemo-hydro-mechanic behaviour of hydraulic barrier reinforced by polymer

International Nuclear Information System (INIS)

Razakamanantsoa, Andry Rico

2009-01-01

Passive barrier for landfill liners are designed with bentonite material as Geo-synthetic Clay Liners (GCL's) or Sand Bentonite Mixtures (SBM). This thesis is focused on the experimental study of the long term Chemo-Hydro-Mechanic behaviour of polymer treated geo-materials. Tests are performed with two powder polyelectrolyte polymers (P1, P2). Soil and one selected type of bentonite from a set of six are used. The corresponding testing fluid is composed with: synthesized leachate, CaCl_2 and NaCl. This first step of the study is to select the suitable bentonite (B) and the corresponding polymer concentration (2%) that gives the best swelling ability to the bentonite. Compatibility test of the bentonite polymer mixture with synthesized leachable is done. Tests are performed by fabricating GL's, with filter press and oedo-permeameter. Results show that hydraulic performance grows with the bentonite concentration. And the LS aggressiveness occurs immediately in a case of bentonite. The effects of polymer treatment are different: P1 increases the swelling ability of bentonite by flocculation, P2 increases the hydraulic performance of the bentonite by dispersion. The long term hydraulic performance tests with SBM are carried out with a rigid wall permeameter. Tests results show that pre-hydration delays only the fluid aggressiveness in spite of reducing the corresponding effects. The long term effect of polymer treatment reveals benefits to geo-material behaviour by increasing water retention and reducing the undesired effects of pollutant. The chemical index is proposed to forecast the geo-material degradation. (author)

Hydraulic Behavior and Chemical Characterization of Lapilli as Material for Natural Filtering of Slurry

Directory of Open Access Journals (Sweden)

Nereida Falcón-Cardona

2015-06-01

Full Text Available Livestock effluents are a beneficial nutrient supply for crops, whereby their use is critical to ensure the sustainability of the farms global management. However, they can cause serious ecological problems if misused, polluting soils and groundwater. Combining “soft technology” and local materials is a low cost solution in terms of finance and energy. The REAGUA project (REuso AGUA, Water reuse in Spanish analyzes the possibility of using “picon” (lapilli as a material for the treatment of liquid manure from ruminants, for later use in subsurface drip irrigation system to produce forage and biofuels, in which the soil acts as a subsequent advanced treatment. A three-phase system, in which the effluent was poured with a vertical subsurface flow in an unsaturated medium, is designed. In order to determine the management conditions that optimize the filter, it was necessary to characterize the hydraulic behavior of lapilli and its ability to remove substances. Using three lapilli-filled columns, unsaturated flux, and a ruminant effluent, the reduction of chemical oxygen demand (COD, biochemical oxygen demand after 5 days (BOD5 and ammonia, phosphorus and suspension solids (SS obtained was over 80%, 90%, and 95% respectively, assumable values for irrigation.

Assimilation of temperature and hydraulic gradients for quantifying the spatial variability of streambed hydraulics

Science.gov (United States)

Huang, Xiang; Andrews, Charles B.; Liu, Jie; Yao, Yingying; Liu, Chuankun; Tyler, Scott W.; Selker, John S.; Zheng, Chunmiao

2016-08-01

Understanding the spatial and temporal characteristics of water flux into or out of shallow aquifers is imperative for water resources management and eco-environmental conservation. In this study, the spatial variability in the vertical specific fluxes and hydraulic conductivities in a streambed were evaluated by integrating distributed temperature sensing (DTS) data and vertical hydraulic gradients into an ensemble Kalman filter (EnKF) and smoother (EnKS) and an empirical thermal-mixing model. The formulation of the EnKF/EnKS assimilation scheme is based on a discretized 1D advection-conduction equation of heat transfer in the streambed. We first systematically tested a synthetic case and performed quantitative and statistical analyses to evaluate the performance of the assimilation schemes. Then a real-world case was evaluated to calculate assimilated specific flux. An initial estimate of the spatial distributions of the vertical hydraulic gradients was obtained from an empirical thermal-mixing model under steady-state conditions using a constant vertical hydraulic conductivity. Then, this initial estimate was updated by repeatedly dividing the assimilated specific flux by estimates of the vertical hydraulic gradients to obtain a refined spatial distribution of vertical hydraulic gradients and vertical hydraulic conductivities. Our results indicate that optimal parameters can be derived with fewer iterations but greater simulation effort using the EnKS compared with the EnKF. For the field application in a stream segment of the Heihe River Basin in northwest China, the average vertical hydraulic conductivities in the streambed varied over three orders of magnitude (5 × 10-1 to 5 × 102 m/d). The specific fluxes ranged from near zero (qz < ±0.05 m/d) to ±1.0 m/d, while the vertical hydraulic gradients were within the range of -0.2 to 0.15 m/m. The highest and most variable fluxes occurred adjacent to a debris-dam and bridge pier. This phenomenon is very likely

Seabed Filter Feasibility Study of Om Almisk Island

KAUST Repository

Sesler, Kathryn

2012-06-01

Freshwater access has always been and is continuing to be a severe problem in desert coastal regions, despite the fact that they have an unlimited supply of easily accessible saline water. Water desalination plants are well established and heavily relied upon throughout the Middle East, Saudi Arabia in particular. However, water desalination tends to be a very expensive and energy intensive solution to the problem. The transition from using open water intake systems and all of the pretreatment processes that they require, to using seabed water filters as an intake, would potentially reduce the lifetime costs, energy consumption, and environmental impacts commonly associated with water desalination. This is because the filtration process that the seabed filter generates, serves as sufficient pretreatment for seawater as well as eliminating any risk of entrainment or impingement of marine organisms. The main objective of this research is to conduct a feasibility study on Om Almisk Island, an island off the coast of King Abdullah University of Science and Technology (KAUST), to determine if it would be a suitable location to construct a seabed water filter as a replacement for the current open water intake. The Om Almisk Island site was evaluated through collection of sand samples over a radial grid around Om Almisk Island and sample analysis using grain size distribution, porosity, and hydraulic conductivity. The lack of mud, high hydraulic conductivity, proximity to KAUST, and the shallow waters of the sandy apron surrounding Om Almisk Island make this an ideal location for a seabed water filter to be used as an intake and pretreatment for the KAUST desalination plant. This location also has low tide change and the presence of benthic macrofauna to create bioturbation in the sediments, which could inhibit the growth of a schmutzdecke. If this biological layer forms, it could drastically reduce the hydraulic conductivity of the system. Due to the high hydraulic

The importance of hydraulic architecture to the distribution patterns of trees in a central Amazonian forest.

Science.gov (United States)

Cosme, Luiza H M; Schietti, Juliana; Costa, Flávia R C; Oliveira, Rafael S

2017-07-01

Species distributions and assemblage composition may be the result of trait selection through environmental filters. Here, we ask whether filtering of species at the local scale could be attributed to their hydraulic architectural traits, revealing the basis of hydrological microhabitat partitioning in a Central Amazonian forest. We analyzed the hydraulic characteristics at tissue (anatomical traits, wood specific gravity (WSG)), organ (leaf area, specific leaf area (SLA), leaf area : sapwood area ratio) and whole-plant (height) levels for 28 pairs of congeneric species from 14 genera restricted to either valleys or plateaus of a terra-firme forest in Central Amazonia. On plateaus, species had higher WSG, but lower mean vessel area, mean vessel hydraulic diameter, sapwood area and SLA than in valleys; traits commonly associated with hydraulic safety. Mean vessel hydraulic diameter and mean vessel area increased with height for both habitats, but leaf area and leaf area : sapwood area ratio investments with tree height declined in valley vs plateau species. [Correction added after online publication 29 March 2017: the preceding sentence has been reworded.] Two strategies for either efficiency or safety were detected, based on vessel size or allocation to sapwood. In conclusion, contrasting hydrological conditions act as environmental filters, generating differences in species composition at the local scale. This has important implications for the prediction of species distributions under future climate change scenarios. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Effects of dynamic operating conditions on nitrification in biological rapid sand filters for drinking water treatment

DEFF Research Database (Denmark)

Lee, Carson Odell; Boe-Hansen, Rasmus; Musovic, Sanin

2014-01-01

Biological rapid sand filters are often used to remove ammonium from groundwater for drinking water supply. They often operate under dynamic substrate and hydraulic loading conditions, which can lead to increased levels of ammonium and nitrite in the effluent. To determine the maximum nitrification...... operating conditions. The ammonium removal rate of the filter was determined by the ammonium loading rate, but was independent of both the flow and influent ammonium concentration individually. Ammonia-oxidizing bacteria and archaea were almost equally abundant in the filter. Both ammonium removal...... rates and safe operating windows of rapid sand filters, a pilot scale rapid sand filter was used to test short-term increased ammonium loads, set by varying either influent ammonium concentrations or hydraulic loading rates. Ammonium and iron (flock) removal were consistent between the pilot...

Forming of AHSS using Servo-Presses

Science.gov (United States)

Groseclose, Adam Richard

Stamping of Advanced High Strength Steel (AHSS) alloys poses several challenges due to the material's higher strength and low formability compared to conventional steels and other problems such as (a) inconsistency of incoming material properties, (b) ductile fracture during forming, (c) higher contact pressure and temperature rise during forming, (d) higher die wear leading to reduced tool life, (e) higher forming load/press capacity, and (f) large springback leading to dimensional inaccuracy in the formed part. [Palaniswamy et. al., 2007]. The use of AHSS has been increasing steadily in automotive stamping. New AHSS alloys (TRIP, TWIP) may replace some of the Hot Stamping applications. Stamping of AHSS alloys, especially higher strength materials, 780 MPa and higher, present new challenges in obtaining good part definition (corner and fillet radii), formability (fracture and resulting scrap) and in reducing springback. Servo-drive presses, having the capability to have infinitely variable and adjustable ram speed and dwell at BDC, offer a potential improvement in quality, part definition, and springback reduction especially when the infinitely adjustable slide motion is used in combination with a CNC hydraulic cushion. Thus, it is desirable to establish a scientific/engineering basis for improving the stamping conditions in forming AHSS using a servo-drive press.

Hydraulic Presses,

Science.gov (United States)

1984-03-09

inaccuracy in the sizes/dimensions along the length of prepared/ prefabricated for the installation ducts/tubes/pipes. Flange joints depending on the...of pump in its housing is an auxiliary cylinder 3, connected with the working line. The plunger of cylinder abut against the unit of pump and is

Sand filter clogging by septic tank effluent.

Science.gov (United States)

Spychała, M; Błazejewski, R

2003-01-01

The aim of this study was to characterise conditions and factors affecting fine sand clogging by septic tank effluent on the basis of physical modelling. The physical model consisted of 12 sand columns dosed with sewage from one household (5 persons), preliminary treated in a septic tank. Hydraulic loadings of the sand filters were equal to 82 mm/d. The mean discharge from sand columns, measured as the effluent volume collected during 10 minutes, decreased significantly over the experiment period from 34 cm3/min in August 2000 to 20 cm3/min in August 2001 at the same temperature of about 20 degrees C. First the columns clogged almost completely after 480 days in December 2001, however six columns had remained unclogged till the end of the experiment (March 2002). The temperature had a significant impact on hydraulic conductivity. A vertical distribution of accumulated mass and biomass was investigated in partly clogged sand. Microscopic survey of the clogging layer showed a presence of live micro-organisms, residuals of dead micro-organisms, particularly pieces of small animal armour and many fibres. These particles accelerated the accumulation of solids in the upper clogging layer. The study indicated that temperature impact on the filter hydraulic conductivity was more significant for biological activity, than for sewage viscosity.

Arsenic and fluoride removal from groundwater by electrocoagulation using a continuous filter-press reactor.

Science.gov (United States)

Guzmán, Athziri; Nava, José L; Coreño, Oscar; Rodríguez, Israel; Gutiérrez, Silvia

2016-02-01

We investigated simultaneous arsenic and fluoride removal from ground water by electrocoagulation (EC) using aluminum as the sacrificial anode in a continuous filter-press reactor. The groundwater was collected at a depth of 320 m in the Bajío region in Guanajuato Mexico (arsenic 43 µg L(-1), fluoride 2.5 mg L(-1), sulfate 89.6 mg L(-1), phosphate 1.8 mg L(-1), hydrated silica 112.4 mg L(-1), hardness 9.8 mg L(-1), alkalinity 31.3 mg L(-1), pH 7.6 and conductivity 993 µS cm(-1)). EC was performed after arsenite was oxidized to arsenate by addition of 1 mg L(-1) hypochlorite. The EC tests revealed that at current densities of 4, 5 and 6 mA cm(-2) and flow velocities of 0.91 and 1.82 cm s(-1), arsenate was abated and residual fluoride concentration satisfies the WHO standard (CF < 1.5 mg L(-1)). Spectrometric analyses performed on aluminum flocs indicated that these are mainly composed of aluminum-silicates of calcium and magnesium. Arsenate removal by EC involves adsorption on aluminum flocs, while fluoride replaces a hydroxyl group from aluminum aggregates. The best EC was obtained at 4 mA cm(-2) and 1.82 cm s(-1) with electrolytic energy consumption of 0.34 KWh m(-3). Copyright © 2015 Elsevier Ltd. All rights reserved.

Kalman filters for assimilating near-surface observations into the Richards equation - Part 2: A dual filter approach for simultaneous retrieval of states and parameters

Science.gov (United States)

Medina, H.; Romano, N.; Chirico, G. B.

2014-07-01

This study presents a dual Kalman filter (DSUKF - dual standard-unscented Kalman filter) for retrieving states and parameters controlling the soil water dynamics in a homogeneous soil column, by assimilating near-surface state observations. The DSUKF couples a standard Kalman filter for retrieving the states of a linear solver of the Richards equation, and an unscented Kalman filter for retrieving the parameters of the soil hydraulic functions, which are defined according to the van Genuchten-Mualem closed-form model. The accuracy and the computational expense of the DSUKF are compared with those of the dual ensemble Kalman filter (DEnKF) implemented with a nonlinear solver of the Richards equation. Both the DSUKF and the DEnKF are applied with two alternative state-space formulations of the Richards equation, respectively differentiated by the type of variable employed for representing the states: either the soil water content (θ) or the soil water matric pressure head (h). The comparison analyses are conducted with reference to synthetic time series of the true states, noise corrupted observations, and synthetic time series of the meteorological forcing. The performance of the retrieval algorithms are examined accounting for the effects exerted on the output by the input parameters, the observation depth and assimilation frequency, as well as by the relationship between retrieved states and assimilated variables. The uncertainty of the states retrieved with DSUKF is considerably reduced, for any initial wrong parameterization, with similar accuracy but less computational effort than the DEnKF, when this is implemented with ensembles of 25 members. For ensemble sizes of the same order of those involved in the DSUKF, the DEnKF fails to provide reliable posterior estimates of states and parameters. The retrieval performance of the soil hydraulic parameters is strongly affected by several factors, such as the initial guess of the unknown parameters, the wet or dry

Six-axis multi-anvil press for high-pressure, high-temperature neutron diffraction experiments

Energy Technology Data Exchange (ETDEWEB)

Sano-Furukawa, A., E-mail: sano.asami@jaea.go.jp; Hattori, T. [Quantum Beam Science Center, Japan Atomic Energy Agency, Ibaraki 319-1195 (Japan); J-PARC Center, Japan Atomic Energy Agency, Ibaraki 319-1195 (Japan); Arima, H. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Yamada, A. [The University of Shiga Prefecture, Shiga 522-8533 (Japan); Tabata, S.; Kondo, M.; Nakamura, A. [Sumitomo Heavy Industries Co., Ltd., Ehime 792-0001 (Japan); Kagi, H.; Yagi, T. [Geochemical Research Center, Graduate School of Science, The University of Tokyo, Tokyo 113-0033 (Japan)

2014-11-15

We developed a six-axis multi-anvil press, ATSUHIME, for high-pressure and high-temperature in situ time-of-flight neutron powder diffraction experiments. The press has six orthogonally oriented hydraulic rams that operate individually to compress a cubic sample assembly. Experiments indicate that the press can generate pressures up to 9.3 GPa and temperatures up to 2000 K using a 6-6-type cell assembly, with available sample volume of about 50 mm{sup 3}. Using a 6-8-type cell assembly, the available conditions expand to 16 GPa and 1273 K. Because the six-axis press has no guide blocks, there is sufficient space around the sample to use the aperture for diffraction and place an incident slit, radial collimators, and a neutron imaging camera close to the sample. Combination of the six-axis press and the collimation devices realized high-quality diffraction pattern with no contamination from the heater or the sample container surrounding the sample. This press constitutes a new tool for using neutron diffraction to study the structures of crystals and liquids under high pressures and temperatures.

A superconducting solenoid and press for permanent magnet fabrication

International Nuclear Information System (INIS)

Mulcahy, T. M.; Hull, J. R.

2002-01-01

For the first time, a superconducting solenoid (SCM) was used to increase the remnant magnetization of sintered NdFeB permanent magnets (PMs). In particular, improved magnetic alignment of commercial-grade PM powder was achieved, as it was axial die pressed into 12.7-mm diameter cylindrical compacts in the 76.2-mm warm bore of a 9-T SCM. The press used to compact the powder is unique and was specifically designed for use with the SCM. Although the press was operated in the batch mode for this proof of concept study, its design is intended to enable automated production. In operation, a simple die and punch set made of nonmagnetic materials was filled with powder and loaded into a nonmagnetic press tube. The cantilevered press tube was inserted horizontally, on a carrier manually advanced along a track, into the SCM. The robustness of the mechanical components and the SCM, in its liquid helium dewar, were specifically designed to allow for insertion and extraction of the magnetic powder and compacts, while operating at 9 T. Compaction was achieved by pressing the punches between the closed end of the press tube and the hydraulic cylinder mounted on the opposite end. Improvements up to 10% in magnetization and 20% in energy products of the permanent magnets were obtained, as the alignment fields were increased above the 2-T maximum field of the electromagnets used in industry. Increases in magnetization of 3% are significant in the mature sintered magnet industry

Predicting the Hydraulic Conductivity of Metallic Iron Filters: Modeling Gone Astray

Directory of Open Access Journals (Sweden)

Chicgoua Noubactep

2016-04-01

Full Text Available Since its introduction about 25 years ago, metallic iron (Fe0 has shown its potential as the key component of reactive filtration systems for contaminant removal in polluted waters. Technical applications of such systems can be enhanced by numerical simulation of a filter design to improve, e.g., the service time or the minimum permeability of a prospected system to warrant the required output water quality. This communication discusses the relevant input quantities into such a simulation model, illustrates the possible simplifications and identifies the lack of relevant thermodynamic and kinetic data. As a result, necessary steps are outlined that may improve the numerical simulation and, consequently, the technical design of Fe0 filters. Following a general overview on the key reactions in a Fe0 system, the importance of iron corrosion kinetics is illustrated. Iron corrosion kinetics, expressed as a rate constant kiron, determines both the removal rate of contaminants and the average permeability loss of the filter system. While the relevance of a reasonable estimate of kiron is thus obvious, information is scarce. As a conclusion, systematic experiments for the determination of kiron values are suggested to improve the database of this key input parameter to Fe0 filters.

Coil measurement data acquisition and curing press control system for SSC dipole magnet coils

International Nuclear Information System (INIS)

Dickey, C.E.

1989-03-01

A coil matching program, similar in theory to the methods used to match Tevatron coils, is being developed at Fermilab. Modulus of elasticity and absolute coil size will be determined at 18-inch intervals along the coils while in the coil curing press immediately following the curing process. A data acquisition system is under construction to automatically acquire and manage the large quantities of data that result. Data files will be transferred to Fermilab's VAX Cluster for long-term storage and actual coil matching. The data acquisition system will also provide the control algorithm for the curing press hydraulic system. A description of the SSC Curing Press Data Acquisition and Controls System will be reported. 20 figs

Using one filter stage of unsaturated/saturated vertical flow filters for nitrogen removal and footprint reduction of constructed wetlands.

Science.gov (United States)

Morvannou, Ania; Troesch, Stéphane; Esser, Dirk; Forquet, Nicolas; Petitjean, Alain; Molle, Pascal

2017-07-01

French vertical flow constructed wetlands (VFCW) treating raw wastewater have been developed successfully over the last 30 years. Nevertheless, the two-stage VFCWs require a total filtration area of 2-2.5 m 2 /P.E. Therefore, implementing a one-stage system in which treatment performances reach standard requirements is of interest. Biho-Filter ® is one of the solutions developed in France by Epur Nature. Biho-Filter ® is a vertical flow system with an unsaturated layer at the top and a saturated layer at the bottom. The aim of this study was to assess this new configuration and to optimize its design and operating conditions. The hydraulic functioning and pollutant removal efficiency of three different Biho-Filter ® plants commissioned between 2011 and 2012 were studied. Outlet concentrations of the most efficient Biho-Filter ® configuration are 70 mg/L, 15 mg/L, 15 mg/L and 25 mg/L for chemical oxygen demand (COD), 5-day biological oxygen demand (BOD 5 ), total suspended solids (TSS) and total Kjeldahl nitrogen (TKN), respectively. Up to 60% of total nitrogen is removed. Nitrification efficiency is mainly influenced by the height of the unsaturated zone and the recirculation rate. The optimum recirculation rate was found to be 100%. Denitrification in the saturated zone works at best with an influent COD/NO 3 -N ratio at the inflet of this zone larger than 2 and a hydraulic retention time longer than 0.75 days.

Application of Self Cleaning Rapid Sand Filter in Water Treatment

Directory of Open Access Journals (Sweden)

Ali Reza Rahmani

2005-08-01

Full Text Available Rapid sand filter is one of the most important units in the water treatment plants. It has some difficulties in operation such as backwashing. For the solving of this problem a rapid sand filter has designed and built with the self-cleaning backwashing system. This system consist of 3 main constituents; one galvanized siphon and two galvanized steel tanks. One of them is used for filtration and the other used for the storage of filtrated water in elevation for backwashing the system. Water enter from upside of the filter through the inlet pipe, and collected from the under drainage pipe. Then filter water conduct to the storage tank and exit from outlet pipe. In the beginning, the head loss was low, but because of bed clogging by suspended solids, it increases gradually to the designed head loss (1.2m. Then the system is outed of the service automatically and the backwash is began. The main data for the design of system selected from the hydraulic rules of siphons and rapid sand filter criteria. After essential calculations it was constructed and was started operation. For the hydraulic studies a known volume of storage tank was selected and the time needed for the fill (in filtration stage and empty (in backwash stage of water volume with volumetric method were measured. In hydraulic studies the filter surface rate (SOR was selected about 5-7.5m3/m2/hr (1.39-2.08 lit/sec and the flow of water in siphon, during the backwashing was measured 8.7 lit/sec. It can be seen that the siphon passes 4-6 times the inlet raw water thus a negative pressure will created in the siphon which causes the water above the sand bed to be discharged automatically and rinse water from elevated tank flow under the sand bed and back wash it. So according to this study self cleaning rapid sand filter is very useful for water filtration, especially in small population community. The construction of system is rapid, simple and economic.

Potentials of enhancing the physicochemical and functional characteristics of Nigella sativa oil by using the screw pressing technique for extraction

International Nuclear Information System (INIS)

Hamed, S.F.; Shaaban, H.A.; Ramadan, A.A.; Edris, A.E.

2017-01-01

In the current investigation the crude oil of Nigella sativa was extracted from seeds using hydraulic and screw pressing techniques. Different parameters were evaluated in order to find out the appropriate technique to enhance the physicochemical and functional-related characteristics of the extracted crude oil. Results showed that the acid and peroxide values were significantly lower in the screw pressed oil (SPO) than in the hydraulic pressed oil (HPO). The total phenolic content of the SPO was significantly higher than that of HPO. Evaluation of the oxidative stability using the Rancimat test showed that SPO recorded a much higher oxidative stability index (40.07 h) than HPO (0.51 h). The yield of the volatile oil fraction and its contents of thymoquinone isolated from the SPO were higher than that from the HPO. Biological evaluation revealed that the SPO had significantly higher antimicrobial activity than HPO against Listeria monocytogenes and Staphylococcus aureus at 40 μL/well. [es

TRACKING CONTROL FOR A HYDRAULIC DRIVE WITH A PRESSURE COMPENSATOR

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S. V. Aranovskiy

2015-07-01

Full Text Available A problem of tracking control is considered for a hydraulic drive with a pressure compensator that is widespread in the equipment of heavy-duty machines. Method. The control problem is solved by means of a switching sliding-mode controller coupled with static nonlinear compensation and desired velocity feedforward. Main Results. Mathematical model of a hydraulic drive is given in view of the pressure compensator presence. Traditional model of a hydraulic drive is formulated for a system with a spool valve; purpose and principles of operation of the pressure compensator in hydraulic systems are described, and the extended model is presented illustrating compensator contribution to overall system dynamics. It is shown that the obtained model has an input static nonlinearity; the nonlinearity cancellation method is proposed giving the possibility for injection of a desired velocity feedforward term. The control law is chosen as a switching one and two chattering attenuation methods are studied: equivalent control estimation via filtering and sign function integration. Experimental studies are performed at a forestry hydraulic crane prototype and illustrate high tracking accuracy achieved for typical crane motions. Practical Significance. The results are suitable for heavy-duty hydraulic machines automation in construction, road building and forestry.

Parameter importance and uncertainty in predicting runoff pesticide reduction with filter strips.

Science.gov (United States)

Muñoz-Carpena, Rafael; Fox, Garey A; Sabbagh, George J

2010-01-01

Vegetative filter strips (VFS) are an environmental management tool used to reduce sediment and pesticide transport from surface runoff. Numerical models of VFS such as the Vegetative Filter Strip Modeling System (VFSMOD-W) are capable of predicting runoff, sediment, and pesticide reduction and can be useful tools to understand the effectiveness of VFS and environmental conditions under which they may be ineffective. However, as part of the modeling process, it is critical to identify input factor importance and quantify uncertainty in predicted runoff, sediment, and pesticide reductions. This research used state-of-the-art global sensitivity and uncertainty analysis tools, a screening method (Morris) and a variance-based method (extended Fourier Analysis Sensitivity Test), to evaluate VFSMOD-W under a range of field scenarios. The three VFS studies analyzed were conducted on silty clay loam and silt loam soils under uniform, sheet flow conditions and included atrazine, chlorpyrifos, cyanazine, metolachlor, pendimethalin, and terbuthylazine data. Saturated hydraulic conductivity was the most important input factor for predicting infiltration and runoff, explaining >75% of the total output variance for studies with smaller hydraulic loading rates ( approximately 100-150 mm equivalent depths) and approximately 50% for the higher loading rate ( approximately 280-mm equivalent depth). Important input factors for predicting sedimentation included hydraulic conductivity, average particle size, and the filter's Manning's roughness coefficient. Input factor importance for pesticide trapping was controlled by infiltration and, therefore, hydraulic conductivity. Global uncertainty analyses suggested a wide range of reductions for runoff (95% confidence intervals of 7-93%), sediment (84-100%), and pesticide (43-100%) . Pesticide trapping probability distributions fell between runoff and sediment reduction distributions as a function of the pesticides' sorption. Seemingly

FEATURES OF THE REGENERATION PROCESS OF THE FILTER

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S. Yu. Panov

2015-01-01

Full Text Available The regeneration system exercises significant influence on the efficiency and reliability of the filters. During operation of the filter it continuously increases the hydraulic resistance and the gas permeability of the filter material decreases as the deposition of the disperse phase capturable on the filter element, and to maintain the bandwidth of the filter in the filter element within the set must be periodically changed or regenerated. Thus, regeneration of a process of removing part of the dust layer with the purpose of full or partial reduction of the initial filter partitioning properties. On the basis of theoretical synthesis, physico-chemical effects of dust in layers, analysis of energy effects, developed methods of intensification of the process of regeneration of particulate filters. Pneumopulse regeneration of bag filter has been investigated, and based on it a regression equation for regeneration efficiency has been derived. It has been shown that pulse pressure exerts the dominant influence on the regeneration efficiency. The obtained model was used for assessment and prediction of the efficiency of the pneumopulse system of regeneration of bag filters at a number of structural materials producing enterprises in the Voronezh region.

Prediction of Pressing Quality for Press-Fit Assembly Based on Press-Fit Curve and Maximum Press-Mounting Force

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Bo You

2015-01-01

Full Text Available In order to predict pressing quality of precision press-fit assembly, press-fit curves and maximum press-mounting force of press-fit assemblies were investigated by finite element analysis (FEA. The analysis was based on a 3D Solidworks model using the real dimensions of the microparts and the subsequent FEA model that was built using ANSYS Workbench. The press-fit process could thus be simulated on the basis of static structure analysis. To verify the FEA results, experiments were carried out using a press-mounting apparatus. The results show that the press-fit curves obtained by FEA agree closely with the curves obtained using the experimental method. In addition, the maximum press-mounting force calculated by FEA agrees with that obtained by the experimental method, with the maximum deviation being 4.6%, a value that can be tolerated. The comparison shows that the press-fit curve and max press-mounting force calculated by FEA can be used for predicting the pressing quality during precision press-fit assembly.

Hydraulic modelling of drinking water treatment plant operations

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L. C. Rietveld

2009-06-01

Full Text Available The flow through a unit of a drinking water treatment plant is one of the most important parameters in terms of a unit's effectiveness. In the present paper, a new EPAnet library is presented with the typical hydraulic elements for drinking water treatment processes well abstraction, rapid sand filtration and cascade and tower aeration. Using this treatment step library, a hydraulic model was set up, calibrated and validated for the drinking water treatment plant Harderbroek. With the actual valve position and pump speeds, the flows were calculated through the several treatment steps. A case shows the use of the model to calculate the new setpoints for the current frequency converters of the effluent pumps during a filter backwash.

Biological treatment of wastewaters from a dye manufacturing company using a trickling filter

International Nuclear Information System (INIS)

Kornaros, M.; Lyberatos, G.

2006-01-01

The aim of this work was to assess the effectiveness of a biological trickling filter for the treatment of wastewaters produced by a company manufacturing organic dyes and varnishes. The combined wastewater effluent was fed to a pilot-scale trickling filter in two feeding modes, continuously and as a sequencing batch reactor (SBR). The biodegradability of the diluted wastewaters that were subjected to physicochemical treatment, using Ca(OH) 2 and FeSO 4 , was initially studied using a continuously operated trickling filter. The system efficiency ranged up to 60-70% for a hydraulic loading of 1.1 m 3 /m 2 day and up to 80-85% for a hydraulic loading 0.6 m 3 /m 2 day. A stable chemical oxygen demand (COD) removal efficiency of 60-70% was achieved even in the case of undiluted wastewater at a hydraulic loading of 1.1 m 3 /m 2 day. The effectiveness of biological treatment of a mixture of the company's main wastewater streams was also examined. The microorganisms developed in the trickling filter were able to efficiently remove COD levels up to 36,000 mg/L, under aerobic conditions at pH values between 5.5 and 8.0. Depending on the operating conditions of the system, about 30-60% of the total COD removal was attributed to air stripping caused by the air supply at the bottom of the filter, whereas the rest of the COD was clearly removed through biological action. The proposed biological treatment process based on a trickling filter, which was operated either continuously or even better in an SBR mode, appears as a promising pretreatment step for coping with dye manufacturing wastewaters in terms of removing a significant portion of the organic content

Trade-offs between xylem hydraulic properties, wood anatomy and yield in Populus.

Science.gov (United States)

Hajek, Peter; Leuschner, Christoph; Hertel, Dietrich; Delzon, Sylvain; Schuldt, Bernhard

2014-07-01

Trees face the dilemma that achieving high plant productivity is accompanied by a risk of drought-induced hydraulic failure due to a trade-off in the trees' vascular system between hydraulic efficiency and safety. By investigating the xylem anatomy of branches and coarse roots, and measuring branch axial hydraulic conductivity and vulnerability to cavitation in 4-year-old field-grown aspen plants of five demes (Populus tremula L. and Populus tremuloides Michx.) differing in growth rate, we tested the hypotheses that (i) demes differ in wood anatomical and hydraulic properties, (ii) hydraulic efficiency and safety are related to xylem anatomical traits, and (iii) aboveground productivity and hydraulic efficiency are negatively correlated to cavitation resistance. Significant deme differences existed in seven of the nine investigated branch-related anatomical and hydraulic traits but only in one of the four coarse-root-related anatomical traits; this likely is a consequence of high intra-plant variation in root morphology and the occurrence of a few 'high-conductivity roots'. Growth rate was positively related to branch hydraulic efficiency (xylem-specific conductivity) but not to cavitation resistance; this indicates that no marked trade-off exists between cavitation resistance and growth. Both branch hydraulic safety and hydraulic efficiency significantly depended on vessel size and were related to the genetic distance between the demes, while the xylem pressure causing 88% loss of hydraulic conductivity (P88 value) was more closely related to hydraulic efficiency than the commonly used P50 value. Deme-specific variation in the pit membrane structure may explain why vessel size was not directly linked to growth rate. We conclude that branch hydraulic efficiency is an important growth-influencing trait in aspen, while the assumed trade-off between productivity and hydraulic safety is weak. © The Author 2014. Published by Oxford University Press. All rights reserved

The reaction environment in a filter-press laboratory reactor: the FM01-LC flow cell

International Nuclear Information System (INIS)

Rivera, Fernando F.; León, Carlos Ponce de; Walsh, Frank C.; Nava, José L.

2015-01-01

A parallel plate cell facilitating controlled flow in a rectangular channel and capable of incorporating a wide range of electrode materials is important in studies of electrode reactions prior to process development and scale-up. The FM01-LC, a versatile laboratory-scale, plane parallel filter-press type electrochemical cell (having a projected electrode area of 64 cm 2 ) which is based on the larger FM21-SP electrolyser (2100 cm 2 area). Many laboratories have used this type of reactor to quantify the importance of reaction environment in fundamental studies and to prepare for industrial applications. A number of papers have concerned the experimental characterization and computational modelling of its reaction environment but the experimental and computational data has become dispersed. The cell has been used in a diverse range of synthesis and processing applications which require controlled flow and known reaction environment. In a previous review, the cell construction and reaction environment was summarised followed by the illustration of its use for a range of applications that include organic and inorganic electrosynthesis, metal ion removal, energy storage, environmental remediation (e.g., metal recycling or anodic destruction of organics) and drinking water treatment. This complementary review considers the characteristics of the FM01-LC electrolyser as an example of a well-engineered flow cell facilitating cell scale-up and provides a rigorous analysis of its reaction environment. Particular aspects include the influence of electrolyte velocity on mass transport rates, flow dispersion and current distribution

Desenvolvimento e avaliação de um descaroçador e prensa enfardadeira itinerantes para o beneficiamento do algodão Development of a mobile gin and baler press for cotton

Directory of Open Access Journals (Sweden)

Jeane F. Jerônimo

2013-03-01

Full Text Available Novas tecnologias vêm sendo incorporadas ao sistema produtivo da cotonicultura brasileira, visando verticalizar a produção por meio do beneficiamento do algodão em caroço possibilitando, aos produtores ou associações, a agregação de valor à sua produção. Objetivou-se então, com o presente trabalho, desenvolver e avaliar um equipamento de beneficiamento composto de descaroçador e prensa enfardadeira itinerantes. O descaroçador se compõe de: limpador, cilindro de serras, cilindro de escovas, condensador e rolo. A prensa enfardadeira é constituída de chapas de prensagem, cilindros hidráulicos, bomba hidráulica, válvula de controle de acionamento, dispositivos de filtragem do óleo hidráulico e manômetro. Esses equipamentos são montados sobre um reboque composto por chassi de cantoneiras em U, quatro rodas de aro 13, pontas de eixo, dois feixes de cinco molas, lastro em chapa de ferro e sistema de frenagem. Na avaliação e validação do conjunto pelos cotonicultores, este conjunto recebeu o conceito "muito bom" quanto ao rendimento do descaroçador, o peso do fardo e em relação à qualidade da fibra obtida. A qualidade da fibra obtida com o conjunto descaroçador e prensa enfardadeira atendeu aos padrões da indústria têxtil.New technologies have been incorporated into the Brazilian cotton production system, in order to verticalize the production through processing, allowing the producers or associations to add value to their production. Thus, the present study aimed to develop and evaluate processing equipment composed of mobile gin and baler press. The ginner consists of cleaner, saw cylinder, cylinder brushes, condenser and coil. The baler press is constituted of pressing sheets, hydraulic cylinders, hydraulic pump, control valve actuation, devices for filtering hydraulic oil and manometer. These devices are mounted on a trailer chassis composed of U-shaped angle iron chassis, four wheels (rim 13, shaft ends, two

The Effect of the Hydraulic Retention Time on the Performance of an Ecological Wastewater Treatment System: An Anaerobic Filter with a Constructed Wetland

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María L. Merino-Solís

2015-03-01

Full Text Available This work assesses the performance of a municipal pilot wastewater treatment system employing an up-flow anaerobic filter (UAF followed by a horizontal subsurface constructed wetland (HSSCW. This pilot scale demonstration project was implemented in a zone with subtropical climate in order to protect Lake Chapala from wastewater loads that are discharged by small communities in the Lake’s vicinity. The filters were filled with tezontle as the media for biofilm support and the HSSCW was planted with two ornamental plants species, Canna hybrids and Strelitzia reginae. The experiment evaluated three hydraulic retention times (HRT of 18, 28 and 38 h in the UAF, which corresponds to two, three and four days in HSSCW over 66 weeks. The mean efficiencies found for the complete system were 80% and 90% of BOD, 80% and 86% of COD, 30% and 33% of Ntot and between 24% and 44% of Ptot. It was possible to remove almost 80% of organic matter in 18 h in the UAF while the HSSCW reached 30% of removal for Ntot in a HRT of three days. As expected, the UAF was responsible for removing most of the organic matter and the HSSCW removed most of the nitrogen.

Automatic Hydraulic Jack Inbuilt In A Four Wheeler

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Parth M. Patel

2015-08-01

Full Text Available With increasing levels of technology efforts being put to increase the comfort and safety. These can be done by implementation of better design. This paper describes Implementation of Automatic hydraulic jack Mechanism in a four wheeler itself. The jack will be powered by the battery. So at a time of puncture to replace the wheel one has to just press the button and the jack which is fitted in the car itself will lift the car.

Geo synthetics in hydraulic and coastal engineering: Filters, revetments and sand filled structures; Geosinteticos en ingenieria hidraulica y costera: filtros, revestimientos y estructuras llenas de arena

Energy Technology Data Exchange (ETDEWEB)

Bezuijen, A.; Pilarczyk, K. W.

2014-02-01

The paper deals with 2 applications of geo textiles in coastal and hydraulic engineering: Geo textiles in filters and revetments; and geo textiles in sand filled structure. Geo textiles are often replacing granular filters. However, they have different properties than a granular filter. For the application of geo textiles in revetments, the consequences of the different properties will be shown: how permeability is influenced by a geo textile and what can be the consequences of the weight differences between granular and geo textile filters. In the other application, the filter properties of geo textiles are only secondary. In geo textile tubes and containers the geo textile is used as wrapping material to create large unties that will not erode during wave attach. the structures with geo textile tubes and containers serve as an alternative for rock based structures. The first of these structures were more or less constructed by trial and error, but research on the shape of the structures, the stability under wave attach and the durability of the used of the used material has given the possibility to use design tools for these structures. Recently also the morphological aspects of these structures have been investigated. This is of importance because regularly structures with geo textile tubes fail due to insufficient toe protection against the scour hole that that develops in front of the structure, leading to undermining of the structure. Recent research in the Dealt Flume of Deltares and the Large Wave Flume in Hannover has led to better understanding what mechanisms determine the stability under wave attach. It is shown that also the degree of filling is of importance and the position of the water level with respect to the tube has a large influence. (Author)

Electrochemical oxidation of cyanide on 3D Ti-RuO2 anode using a filter-press electrolyzer.

Science.gov (United States)

Pérez, Tzayam; López, Rosa L; Nava, José L; Lázaro, Isabel; Velasco, Guillermo; Cruz, Roel; Rodríguez, Israel

2017-06-01

The novelty of this communication lies in the use of a Ti-RuO 2 anode which has not been tested for the oxidation of free cyanide in alkaline media at concentrations similar to those found in wastewater from the Merrill Crowe process (100 mg L -1 KCN and pH 11), which is typically used for the recovery of gold and silver. The anode was prepared by the Pechini method and characterized by SEM. Linear sweep voltammetries on a Ti-RuO 2 rotating disk electrode (RDE) confirmed that cyanide is oxidized at 0.45 cyanide was investigated on Ti-RuO 2 meshes fitted into a filter-press electrolyzer. Bulk electrolyzes were performed at constant potentials of 0.85 V and 0.95 V and at different mean linear flow rates ranging between 1.2 and 4.9 cm s -1 . The bulk anodic oxidation of cyanide at 0.85 V and 3.7 cm s -1 achieved a degradation of 94%, with current efficiencies of 38% and an energy consumption of 24.6 kWh m -3 . Moreover, the degradation sequence of cyanide was also examined by HPLC. Copyright © 2017 Elsevier Ltd. All rights reserved.

Different depth intermittent sand filters for laboratory treatment of synthetic wastewater with concentrations close to measured septic tank effluent.

Science.gov (United States)

Rodgers, M; Walsh, G; Healy, M G

2011-01-01

The objective of this study was to apply hydraulic and chemical oxygen demand (COD) loading rates at the upper limits of the design criteria for buried sand filters to test the sand filter depth design criteria. Over a 274-day study duration, synthetic effluent with a strength of domestic wastewater was intermittently dosed onto two sand filters of 0.2 m diameter, with depths of 0.3 and 0.4 m. Hydraulic and organic carbon loading rates of 105 L m(-2) d(-1) and 40 g COD m(-2) d(-1), respectively, were applied to the filters. The filters did not clog and had good effluent removal capabilities for 274 and 190 days, respectively. However, the 0.3 m-deep filter did experience a reduced performance towards the end of the study period. In the 0.3 and 0.4 m-deep filters, the effluent COD and SS concentrations were less than 86 and 31 mg L(-1), respectively, and nitrification was nearly complete in both these columns. Ortho-phosphorus (PO(4)-P) removal in fine sand and laterite 'upflow' filters, receiving effluent from the 0.3 m-deep filter, was 10% and 44%, respectively.

Fracking in the UK press: Threat dynamics in an unfolding debate

OpenAIRE

Jaspal, Rusi; Nerlich, Brigitte

2014-01-01

Shale gas is a novel source of fossil fuel which is extracted by induced hydraulic fracturing, or “fracking.” This article examines the the socio-political dimension of fracking as manifested in the UK press at three key temporal points in the debate on the practice. Three newspaper corpora were analysed qualitatively using Thematic Analysis and Social Representations Theory. Three overarching themes are discussed: “April-May 2011: From Optimism to Scepticism”; “November 2011: ...

Decentralized wastewater treatment using passively aerated biological filter.

Science.gov (United States)

Abou-Elela, Sohair I; Hellal, Mohamed S; Aly, Olfat H; Abo-Elenin, Salah A

2017-10-13

This study aimed to evaluate the efficiency of a novel pilot-scale passively aerated biological filter (PABF) as a low energy consumption system for the treatment of municipal wastewater. It consists of four similar compartments, each containing 40% of a non-woven polyester fabric as a bio-bed. The PABF was fed with primary treated wastewater under a hydraulic retention time (HRT) of 3.5 hr and a hydraulic loading rate of 5.5 m 2 /m 3 /d. The effect of media depth, HRT, dissolved oxygen (DO) and surface area of the media on the removal efficiency of pollutants was investigated. Results indicated that increasing media depth along the axis of the reactor and consequently increasing the HRT and DO resulted in great removal of different pollutants. A significant increase in the DO levels in the final effluent up to 6.7 mg/l resulted in good nitrification processes. Statistical analysis using SPSS showed that the reactor performance has significant removal efficiency (p filter systems.

Relationship between self-priming and hydraulic behavior in Venturi Scrubber

International Nuclear Information System (INIS)

Horiguchi, Naoki; Kaneko, Akiko; Abe, Yutaka; Yoshida, Hiroyuki

2014-01-01

As revealed by Fukushima Daiichi nuclear disaster, countermeasures against severe accident in nuclear power plants are an urgent need. In particular, from the viewpoint of protecting a containment and suppressing the diffusion of radioactive materials, it is important to develop the device which allows a filtered venting of contaminated high pressure gas. In the filtered venting system that used in European reactors, so called Multi Venturi Scrubbers System is used to realize filtered venting without any power supply (Lindau, 1988) (Rust, et al., 1995). The system operates with any power supply and high pressure gas filled in the containment. This system is able to define to be composed of Venturi Scrubbers (VS) and a bubble column. In the VS, scrubbing of contaminated gas is promoted by both gas releases through a submerged VS and gas-liquid contact with splay flow formed by liquid suctioned through a hole provided by the pressure difference between inner and outer parts of a throat part of the VS. This type of the VS is called self-priming ones. However, the scrubbing mechanism of the self-priming VS including effects of gas mass flow rate and shape of the VS are understood insufficiently in the previous studies. In this study, to understand the VS operation characteristics for the filtered venting, we discussed the mechanisms of the self-priming phenomena and the hydraulic behavior in the VS. In this paper, we conducted a visualized observation of the hydraulic behavior in the VS and measured liquid flow rate of the self-priming. As a result, it is shown that there is the possibility that the VS decontamination performance falls low level with no self-priming. (author)

Aircraft Hydraulic System Leakage Detection and Servicing Recommendations Method

Science.gov (United States)

2014-10-02

ITA), Brazil. He is with Empresa Brasileira de Aeronáutica S.A (EMBRAER), São José dos Campos, SP, Brazil, since 2007. He works as a Development...degree in Control Engineering from Universidade Estadual de Campinas (Unicamp, 2004), Brazil, and a Master Degree in Aeronautical Engineering from...accumulators, filters, and consumers, that include all the actuators connected to the hydraulic power such as flight controls , brake and landing

Hydrogen production from a rectangular horizontal filter press Divergent Electrode-Flow-Through (DEFT™) alkaline electrolysis stack

Science.gov (United States)

Gillespie, M. I.; Kriek, R. J.

2017-12-01

A membraneless Divergent Electrode-Flow-Through (DEFT™) alkaline electrolyser, for unlocking profitable hydrogen production by combining a simplistic, inexpensive, modular and durable design, capable of overcoming existing technology current density thresholds, is ideal for decentralised renewable hydrogen production, with the only requirement of electrolytic flow to facilitate high purity product gas separation. Scale-up of the technology was performed, representing a deviation from the original tested stack design, incorporating elongated electrodes housed in a filter press assembly. The pilot plant operating parameters were limited to a low flow velocity range (0.03 m s-1 -0.04 m s-1) with an electrode gap of 2.5 mm. Performance of this pilot plant demonstrated repeatability to results previously obtained. Mesh electrodes with geometric area of 344.32 cm2 were used for plant performance testing. A NiO anode and Ni cathode combination developed optimal performance yielding 508 mA cm-2 at 2 VDC in contrast to a Ni anode and cathode combination providing 467 mA cm-2 at 2.26 VDC at 0.04 m s-1, 30% KOH and 80 °C. An IrO2/RuO2/TiO2 anode and Pt cathode combination underwent catalyst deactivation. Owing to the nature of the gas/liquid separation system, gas qualities were inadequate compared to results achieved previously. Future improvements will provide qualities similar to results achieved before.

INFORMATION-MEASURING TEST SYSTEM OF DIESEL LOCOMOTIVE HYDRAULIC TRANSMISSIONS

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I. V. Zhukovytskyy

2015-08-01

Full Text Available Purpose. The article describes the process of developing the information-measuring test system of diesel locomotives hydraulic transmission, which gives the possibility to obtain baseline data to conduct further studies for the determination of the technical condition of diesel locomotives hydraulic transmission. The improvement of factory technology of post-repair tests of hydraulic transmissions by automating the existing hydraulic transmission test stands according to the specifications of the diesel locomotive repair enterprises was analyzed. It is achieved based on a detailed review of existing foreign information-measuring test systems for hydraulic transmission of diesel locomotives, BelAZ earthmover, aircraft tug, slag car, truck, BelAZ wheel dozer, some brands of tractors, etc. The problem for creation the information-measuring test systems for diesel locomotive hydraulic transmission is being solved, starting in the first place from the possibility of automation of the existing test stand of diesel locomotives hydraulic transmission at Dnipropetrovsk Diesel Locomotive Repair Plant "Promteplovoz". Methodology. In the work the researchers proposed the method to create a microprocessor automated system of diesel locomotives hydraulic transmission stand testing in the locomotive plant conditions. It acts by justifying the selection of the necessary sensors, as well as the application of the necessary hardware and software for information-measuring systems. Findings. Based on the conducted analysis there was grounded the necessity of improvement the plant hydraulic transmission stand testing by creating a microprocessor testing system, supported by the experience of developing such systems abroad. Further research should be aimed to improve the accuracy and frequency of data collection by adopting the more modern and reliable sensors in tandem with the use of filtering software for electromagnetic and other interference. Originality. The

Hydraulic Pump Fault Diagnosis Control Research Based on PARD-BP Algorithm

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LV Dongmei

2014-12-01

Full Text Available Combining working principle and failure mechanism of RZU2000HM hydraulic press, with its present fault cases being collected, the working principle of the oil pressure and faults phenomenon of the hydraulic power unit –swash-plate axial piston pump were studied with some emphasis, whose faults will directly affect the dynamic performance of the oil pressure and flow. In order to make hydraulic power unit work reliably, PARD-BP (Pruning Algorithm based Random Degree neural network fault algorithm was introduced, with swash-plate axial piston pump’s vibration fault sample data regarded as input, and fault mode matrix regarded as target output, so that PARD-BP algorithm could be trained. In the end, the vibration results were verified by the vibration modal test, and it was shown that the biggest upward peaks of vacuum pump in X-direction, Y-direction and Z- direction have fallen by 30.49 %, 21.13 % and 18.73 % respectively, so that the reliability of the fact that PARD-BP algorithm could be used for the online fault detection and diagnosis of the hydraulic pump was verified.

Preparation and characterization of monel (70% Ni-30% Cu) metallic filters

International Nuclear Information System (INIS)

Camargo Lavos, I. de.

1993-01-01

This work investigates a process for the fabrication and characterization of monel (Ni-Cu) filters. The powder consolidation was made by vibration or by pressing at various pressures (200, 300 e 400 MPa). The sintering was carried out at 1100 0 C during 1 hour under H 2 atmosphere. The filter characterization was performed by measuring its density, porosity, filtering capacity and permeability. It was obtained a correlation between the processing variables (consolidation and sintering), including powder properties, and the filters characteristics. (author). 59 refs, 41 figs, 7 tabs

Entupimento de gotejadores e seu efeito na pressão da rede hidráulica de um sistema de microirrigação Clogging of drippers and its effect on the hydraulic network pressure in a micro-irrigation system

Directory of Open Access Journals (Sweden)

Luís F. Faria

2002-01-01

Full Text Available Com o presente trabalho, objetivou-se avaliar a sobreelevação de pressão na rede hidráulica de um sistema de irrigação por gotejamento, quando ocorre redução da vazão por entupimento dos emissores. A área avaliada foi de 280 ha, irrigando citrus através de gotejamento subsuperficial, com emissores autocompensantes. A metodologia consistiu num modelo matemático baseado na equação de Bernoulli, utilizando-se uma planilha eletrônica para simular os efeitos do entupimento dos emissores na malha hidráulica. Para estimar a variação de pressão no sistema, simulou-se obstrução dos emissores de 0 a 100%. Para a condição de 50% de entupimento, 80% do comprimento da malha hidráulica apresentaram pressão superior à da classe de pressão da tubulação. O modelo matemático permitiu simular: (a a variação da rotação do conjunto moto-bomba diesel, como possível solução para controle da sobreelevação de pressão na malha hidráulica e (b a variação de pressão na rede, devido ao excesso de rotação no motor diesel (imprecisão no tacômetro. Quando se simularam a situação de 50% de entupimento e 2100 rotações min-1, 98% do comprimento da tubulação apresentaram pressão acima à da classe de pressão da tubulação.The present study attempts to evaluate the pressure increase in the hydraulic network of a micro-irrigation system when partial or total clogging of emitters occurs. The evaluated area was of 280 ha, with citrus irrigation based on subsurface auto-compensating drippers. The methodology utilized a mathematical model based on Bernoulli's equation, simulating the effects of different clogging rates on the network pressure. To evaluate the pressure variation in the system, the obstructions in the range from 0 to 100% were simulated. For the condition of 50% clogging, 80% of the total pipeline length presented hydraulic pressure more than the nominal pressure foreseen in the project. The mathematical model

Study of bioleaching under different hydraulic retention time for enhancing the dewaterability of digestate.

Science.gov (United States)

Li, Linshuai; Gao, Jingqing; Zhu, Songfeng; Li, Yonghong; Zhang, Ruiqin

2015-12-01

Dewatering of kitchen waste digestate is a key problem to solve so as to increase the application of kitchen waste after anaerobic digestion. In this study, the effects of bioleaching under different hydraulic retention time (HRT = 2, 2.5, and 3 days) on dewaterability of kitchen waste digestate were evaluated. A 12-stage plug flow bioreactor with 180 L working volume was used for digestate bioleaching. The bioleached digestate under different HRTs were collected and dewatered by plate-and-frame filter press. The results showed that the moisture contents of digestate cakes were 67.87 % at 2 days of HRT, 58.06 % at 2.5 days of HRT, and 54.45 % at 3 days of HRT, respectively, indicating the longer the HRT, the lower the moisture content of filter cake. Balanced between the cost and practical need, 2.5 days can be used as the HRT in engineering application. Under the condition of HRT of 2.5 days, the pH, specific resistance to filtration (SRF), capillary suction time (CST), and sedimentation rate of digestate changed from the initial values of 8.08, 210.6 s, 23.4 × 10(12) m kg(-1) and 10 % to 3.21, 32.7 s, 2.44 × 10(12) m kg(-1) and 76.8 %, respectively. Based on the observations above, the authors conclude that bioleaching technology is an effective method to enhance digestate dewaterability and reduce the cost of subsequent reutilization.

Biogas production from Jatropha curcas press-cake.

Science.gov (United States)

Staubmann, R; Foidl, G; Foidl, N; Gübitz, G M; Lafferty, R M; Arbizu, V M; Steiner, W

1997-01-01

Seeds of the tropical plant Jatropha curcas (purge nut, physic nut) are used for the production of oil. Several methods for oil extraction have been developed. In all processes, about 50% of the weight of the seeds remain as a press cake containing mainly protein and carbohydrates. Investigations have shown that this residue contains toxic compounds and cannot be used as animal feed without further processing. Preliminary experiments have shown that the residue is a good substrate for biogas production. Biogas formation was studied using a semicontinous upflow anaerobic sludge blanket (UASB) reactor; a contact-process and an anaerobic filter each reactor having a total volume of 110 L. A maximum production rate of 3.5 m3 m"3 d"1 was obtained in the anaerobic filter with a loading rate of 13 kg COD m~3 d"1. However, the UASB reactor and the contact-process were not suitable for using this substrate. When using an anaerobic filter with Jatropha curcas seed cake as a substrate, 76% of the COD was degraded and 1 kg degraded COD yielded 355 L of biogas containing 70% methane.

Biogas production from Jatropha curcas press-cake

Energy Technology Data Exchange (ETDEWEB)

Staubmann, R.; Guebitz, G.M.; Lafferty, R.M. [Graz Technical Univ. (Austria)] [and others

1997-12-31

Seeds of the tropical plant Jatropha curcas (purge nut, physic nut) are used for the production of oil. Several methods for oil extraction have been developed. In all processes, about 50% of the weight of the seeds remain as a press cake containing mainly protein and carbohydrates. Investigations have shown that this residue contains toxic compounds and cannot be used as animal feed without further processing. Preliminary experiments have shown that the residue is a good substrate for biogas production. Biogas formation was studied using a semicontinous upflow anaerobic sludge blanket (UASB) reactor; a contact-process and an anaerobic filter each reactor having a total volume of 110 L. A maximum production rate of 3.5 m{sup 3} m{sup -3} d{sup -1} was obtained in the anaerobic filter with a loading rate of 13 kg COD m{sup -3} d{sup -1}. However, the UAS reactor and the contact-process were not suitable for using this substrate. When using an anaerobic filter with Jatropha curcas seed cake as a substrate, 76% of the COD was degraded and 1 kg degraded COD yielded 355 L of biogas containing 70% methane. 28 refs., 3 figs., 4 tabs.

A new cleaner process to prepare pressing-powder

Directory of Open Access Journals (Sweden)

Shu, Z.

2011-10-01

Full Text Available An alternative cleaner process of pressing-powder preparation, based on filter-pressing and a novel granulation method, is presented to substitute the existing spray-drying process. In the new process, about two-thirds of wet-milled slurry is filterpressed, dried and milled into dry fine powder. The other one-third of the slurry and the as-obtained dry fine powder are spray-mixed in a tower, where the slurry droplets adsorb the dry powder to form granules which are then rolled and dried into a useable pressing-powder for tile pressing. The key stages, filter-pressing and granulation (consisting of spray-mixing and rolling treatment, are specially studied. The pressing-powder properties and pressing/firing behavior, and, energy/water consumption and pollution emission data are presented, and a comparison between the new process and the existing spray-drying process is made. This new process has been found to be feasible and provides a pressing-powder with suitable properties, together with lower energy/water consumption and pollution emission (particulate matter and CO₂.

En ese trabajo se presenta un proceso alternativo y más ecológico para la preparación de polvo de prensas por molienda vía húmeda de las materias primas. En este proceso la eliminación del agua de la suspensión obtenida en la etapa de molienda, en vez de realizarse por secado por atomización, se lleva a cabo en dos etapas, en una primera etapa dos tercios de esta suspensión se filtro-prensan, posteriormente se secan y molturan hasta obtener un polvo seco micronizado. Este material seco se introduce por la parte superior de una torre granuladora, en la que se pulveriza el tercio de la suspensión restante por la parte inferior, de forma que las gotas adsorben sobre su superficie las partículas secas formando gránulos, que posteriormente se compactan por rodamiento (“rolling”, y finalmente se secan hasta la humedad requerida para el prensado. En

Thermal hydraulic analysis of BWR containment venting system

International Nuclear Information System (INIS)

Baburajan, P.K.; Sharma, Prashant; Paul, U.K.; Gaikwad, Avinash

2015-01-01

Installation of additional containment filtered venting system (CFVS) is necessary to depressurize the containment to maintain its mechanical integrity due to over pressurization during severe accident condition. A typical venting system for BWR is modelled using RELAP5 and analysed to investigate the effect of various thermal hydraulic parameters on the operational parameters of the venting system. The venting system consists of piping from the containment to the scrubber tank and exit line from the scrubber tank. The scrubber tank is partially filled with water to enable the scrubbing action to remove the particulate radionuclides from the incoming containment air. The pipe line from the containment is connected to the venturi inlet and the throat of the venturi is open to the scrubber tank water inventory at designed submergence level. The exit of the venturi is open to scrubber tank water. Filters are used in the upper air space of the scrubber tank as mist separator before venting out the air into the atmosphere through the exit vent line. The effect of thermal hydraulic parameters such as inlet fluid temperature, inlet steam content and venturi submergence in the scrubber tank on the venting flow rate, exit steam content, scrubber tank inventory, overflow line and siphon breaker flow rate is analysed. Results show that inlet steam content and the venturi nozzle submergence influence the venting system parameters. (author)

Rotating Ceramic Water Filter Discs System for Water Filtration

Directory of Open Access Journals (Sweden)

Riyadh Z. Al Zubaidy

2017-04-01

Full Text Available This work aimed to design, construct and operate a new laboratory scale water filtration system. This system was used to examine the efficiency of two ceramic filter discs as a medium for water filtration. These filters were made from two different ceramic mixtures of local red clay, sawdust, and water. The filtration system was designed with two rotating interfered modules of these filters. Rotating these modules generates shear force between water and the surfaces of filter discs of the filtration modules that works to reduce thickness of layer of rejected materials on the filters surfaces. Each module consists of seven filtration units and each unit consists of two ceramic filter discs. The average measured hydraulic conductivity of the first module was 13.7mm/day and that for the second module was 50mm/day. Results showed that the water filtration system can be operated continuously with a constant flow rate and the filtration process was controlled by a skin thin layer of rejected materials. The ceramic water filters of both filtration modules have high removal efficiency of total suspended solids up to 100% and of turbidity up to 99.94%.

Deterministic Mean-Field Ensemble Kalman Filtering

KAUST Repository

Law, Kody

2016-05-03

The proof of convergence of the standard ensemble Kalman filter (EnKF) from Le Gland, Monbet, and Tran [Large sample asymptotics for the ensemble Kalman filter, in The Oxford Handbook of Nonlinear Filtering, Oxford University Press, Oxford, UK, 2011, pp. 598--631] is extended to non-Gaussian state-space models. A density-based deterministic approximation of the mean-field limit EnKF (DMFEnKF) is proposed, consisting of a PDE solver and a quadrature rule. Given a certain minimal order of convergence k between the two, this extends to the deterministic filter approximation, which is therefore asymptotically superior to standard EnKF for dimension d<2k. The fidelity of approximation of the true distribution is also established using an extension of the total variation metric to random measures. This is limited by a Gaussian bias term arising from nonlinearity/non-Gaussianity of the model, which arises in both deterministic and standard EnKF. Numerical results support and extend the theory.

Deterministic Mean-Field Ensemble Kalman Filtering

KAUST Repository

Law, Kody; Tembine, Hamidou; Tempone, Raul

2016-01-01

The proof of convergence of the standard ensemble Kalman filter (EnKF) from Le Gland, Monbet, and Tran [Large sample asymptotics for the ensemble Kalman filter, in The Oxford Handbook of Nonlinear Filtering, Oxford University Press, Oxford, UK, 2011, pp. 598--631] is extended to non-Gaussian state-space models. A density-based deterministic approximation of the mean-field limit EnKF (DMFEnKF) is proposed, consisting of a PDE solver and a quadrature rule. Given a certain minimal order of convergence k between the two, this extends to the deterministic filter approximation, which is therefore asymptotically superior to standard EnKF for dimension d<2k. The fidelity of approximation of the true distribution is also established using an extension of the total variation metric to random measures. This is limited by a Gaussian bias term arising from nonlinearity/non-Gaussianity of the model, which arises in both deterministic and standard EnKF. Numerical results support and extend the theory.

Dolomitic lime containing hydraulic additive

International Nuclear Information System (INIS)

Lagzdina, S.; Sedmalis, U.; Bidermanis, L.; Liepins, J.; Grosvalds, I.

1997-01-01

To obtain qualitative dolomitic lime the optimum calcination temperature of dolomite containing about 9 % of clayey substances is 900 deg C. The mechanical strength of dolomitic lime containing 30 % of brick waste additive after 6-9 months of hardening is 1.4-1.5 times higher than that of samples without hydraulic additive, for calcium lime - 2.2-2.6 times higher. Generally the mechanical strength of dolomitic lime is higher than that one of calcium lime. It can be explained by the active role of MgO in the hydration and hardening processes of dolomitic lime. Xray diffraction phase analysis was performed by X-ray diffractometer DPON-3M with Cu-K α emission filter

Performance evaluation and modelling studies of gravel--coir fibre--sand multimedia stormwater filter.

Science.gov (United States)

Samuel, Manoj P; Senthilvel, S; Tamilmani, D; Mathew, A C

2012-09-01

A horizontal flow multimedia stormwater filter was developed and tested for hydraulic efficiency and pollutant removal efficiency. Gravel, coconut (Cocos nucifera) fibre and sand were selected as the media and filled in 1:1:1 proportion. A fabric screen made up of woven sisal hemp was used to separate the media. The adsorption behaviour of coir fibre was determined in a series of column and batch studies and the corresponding isotherms were developed. The hydraulic efficiency of the filter showed a diminishing trend as the sediment level in inflow increased. The filter exhibited 100% sediment removal at lower sediment concentrations in inflow water (>6 g L(-1)). The filter could remove NO3(-), SO4(2-) and total solids (TS) effectively. Removal percentages of Mg(2+) and Na(+) were also found to be good. Similar results were obtained from a field evaluation study. Studies were also conducted to determine the pattern of silt and sediment deposition inside the filter body. The effects of residence time and rate of flow on removal percentages of NO3(-) and TS were also investigated out. In addition, a multiple regression equation that mathematically represents the filtration process was developed. Based on estimated annual costs and returns, all financial viability criteria (internal rate of return, net present value and benefit-cost ratio) were found favourable and affordable to farmers for investment in the developed filtration system. The model MUSIC was calibrated and validated for field conditions with respect to the developed stormwater filter.

Filter media properties of mineral fibres produced by plasma spray.

Science.gov (United States)

Prasauskas, Tadas; Matulevicius, Jonas; Kliucininkas, Linas; Krugly, Edvinas; Valincius, Vitas; Martuzevicius, Dainius

2016-01-01

The purpose of this study was to determine the properties of fibrous gas filtration media produced from mineral zeolite. Fibres were generated by direct current plasma spray. The paper characterizes morphology, chemical composition, geometrical structure of elementary fibres, and thermal resistance, as well as the filtration properties of fibre media. The diameter of the produced elementary fibres ranged from 0.17 to 0.90 μm and the length ranged from 0.025 to 5.1 mm. The release of fibres from the media in the air stream was noticed, but it was minimized by hot-pressing the formed fibre mats. The fibres kept their properties up to the temperature of 956°C, while further increase in temperature resulted in the filter media becoming shrunk and brittle. The filtration efficiency of the prepared filter mats ranged from 95.34% to 99.99% for aerosol particles ranging in a size between 0.03 and 10.0 μm. Unprocessed fibre media showed the highest filtration efficiency when filtering aerosol particles smaller than 0.1 µm. Hot-pressed filters were characterized by the highest quality factor values, ranging from 0.021 to 0.064 Pa(-1) (average value 0.034 Pa(-1)).

Thermal-Hydraulic Performance of Scrubbing Nozzle Used for CFVS

Energy Technology Data Exchange (ETDEWEB)

Lee, Hyun Chul; Lee, Doo Yong; Jung, Woo Young; Lee, Jong Chan; Kim, Gyu Tae [FNC TECH, Yongin (Korea, Republic of)

2016-05-15

A Containment Filtered Venting System (CFVS) is the most interested device to mitigate a threat against containment integrity under the severe accident of nuclear power plant by venting with the filtration of the fission products. FNC technology and partners have been developed the self-priming scrubbing nozzle used for the CFVS which is based on the venturi effect. The thermal-hydraulic performances such as passive scrubbing water suction as well as pressure drop across the nozzle have been tested under various thermal-hydraulic conditions. The two types of test section have been built for testing the thermal-hydraulic performance of the self-priming scrubbing nozzle. Through the visualization loop, the liquid suction performance through the slit, pressure drop across the nozzle are measured. The passive water suction flow through the suction slit at the throat is important parameter to define the scrubbing performance of the self-priming scrubbing nozzle. The water suction flow is increased with the increase of the overhead water level at the same inlet gas flow. It is not so much changed with the change of inlet gas flow at the overhead water level.

Hydraulic structures

CERN Document Server

Chen, Sheng-Hong

2015-01-01

This book discusses in detail the planning, design, construction and management of hydraulic structures, covering dams, spillways, tunnels, cut slopes, sluices, water intake and measuring works, ship locks and lifts, as well as fish ways. Particular attention is paid to considerations concerning the environment, hydrology, geology and materials etc. in the planning and design of hydraulic projects. It also considers the type selection, profile configuration, stress/stability calibration and engineering countermeasures, flood releasing arrangements and scouring protection, operation and maintenance etc. for a variety of specific hydraulic structures. The book is primarily intended for engineers, undergraduate and graduate students in the field of civil and hydraulic engineering who are faced with the challenges of extending our understanding of hydraulic structures ranging from traditional to groundbreaking, as well as designing, constructing and managing safe, durable hydraulic structures that are economical ...

COLLOIDS IN SEPTIC TANK EFFLUENT AND THEIR INFLUENCE ON FILTER PERMEABILITY

Directory of Open Access Journals (Sweden)

Marcin Spychała

2015-09-01

Full Text Available The aim of the study was to evaluate the content of colloids in septic tank effluent and their impact on textile filter permeability. Measurements were performed on septic tank effluent without suspended solids but containing colloids and without colloids - including only dissolved substances (filtered by micro-filters and centrifuged. The study was conducted on unclogged and clogged textile filter coupons. During the study the following measurements were determined: turbidity, chemical oxygen demand and hydraulic conductivity of textile filter coupons. The colloid size range was assumed to be less than 1.2 microns according to the literature. Despite the relatively low content in the septic tank effluent the colloids played an important role in the clogging process. Both the filtering media, filled with low (unclogged and high content of biomass (clogged were sensitive to the clogging process of colloid acceleration due to the possibility of small diameter pore closure and oxygen access termination. Moreover, small size pores were probably sensitive to closing or bridging by small size colloidal particles.

Hydraulic System Design of Hydraulic Actuators for Large Butterfly Valves

Directory of Open Access Journals (Sweden)

Ye HUANG

2014-09-01

Full Text Available Hydraulic control systems of butterfly valves are presently valve-controlled and pump-controlled. Valve-controlled hydraulic systems have serious power loss and generate much heat during throttling. Pump-controlled hydraulic systems have no overflow or throttling losses but are limited in the speed adjustment of the variable-displacement pump, generate much noise, pollute the environment, and have motor power that does not match load requirements, resulting in low efficiency under light loads and wearing of the variable-displacement pump. To overcome these shortcomings, this article designs a closed hydraulic control system in which an AC servo motor drives a quantitative pump that controls a spiral swinging hydraulic cylinder, and analyzes and calculates the structure and parameters of a spiral swinging hydraulic cylinder. The hydraulic system adjusts the servo motor’s speed according to the requirements of the control system, and the motor power matches the power provided to components, thus eliminating the throttling loss of hydraulic circuits. The system is compact, produces a large output force, provides stable transmission, has a quick response, and is suitable as a hydraulic control system of a large butterfly valve.

Effects of Sawdust and Rice husk Additives on Physical Properties of Ceramic Filter

OpenAIRE

Majid. Muhi Shukur; Mohsin Abbas Aswad; Saba Mohamed Bader

2017-01-01

Two processes were employed for forming, specifically,  slip casting and semi-dry press were used to manufacture ceramic filters from local raw materials, red clay and combustible materials  (sawdust and rice husk). Different proportions of additives were used as pores forming agents to create porosity in ceramic filter. Dried filters  were fired at temperature to 1000°C.   It was found that the forming technique and additives have great effect on the physical properties of the produced ...

Species climate range influences hydraulic and stomatal traits in Eucalyptus species.

Science.gov (United States)

Bourne, Aimee E; Creek, Danielle; Peters, Jennifer M R; Ellsworth, David S; Choat, Brendan

2017-07-01

Plant hydraulic traits influence the capacity of species to grow and survive in water-limited environments, but their comparative study at a common site has been limited. The primary aim of this study was to determine whether selective pressures on species originating in drought-prone environments constrain hydraulic traits among related species grown under common conditions. Leaf tissue water relations, xylem anatomy, stomatal behaviour and vulnerability to drought-induced embolism were measured on six Eucalyptus species growing in a common garden to determine whether these traits were related to current species climate range and to understand linkages between the traits. Hydraulically weighted xylem vessel diameter, leaf turgor loss point, the water potential at stomatal closure and vulnerability to drought-induced embolism were significantly ( P Eucalyptus trees has important implications for the limits of species responses to changing environmental conditions and thus for species survival and distribution into the future, and yields new information for physiological models. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Hydraulic Arm Modeling via Matlab SimHydraulics

Czech Academy of Sciences Publication Activity Database

Věchet, Stanislav; Krejsa, Jiří

2009-01-01

Roč. 16, č. 4 (2009), s. 287-296 ISSN 1802-1484 Institutional research plan: CEZ:AV0Z20760514 Keywords : simulatin modeling * hydraulics * SimHydraulics Subject RIV: JD - Computer Applications, Robotics

Effects of Sawdust and Rice husk Additives on Physical Properties of Ceramic Filter

Directory of Open Access Journals (Sweden)

Majid. Muhi Shukur

2017-11-01

Full Text Available Two processes were employed for forming, specifically,  slip casting and semi-dry press were used to manufacture ceramic filters from local raw materials, red clay and combustible materials  (sawdust and rice husk. Different proportions of additives were used as pores forming agents to create porosity in ceramic filter. Dried filters  were fired at temperature to 1000°C.   It was found that the forming technique and additives have great effect on the physical properties of the produced ceramic filters. The slip casting technique was more suitable procedure for producing a porous ceramic filter. As well as, porosity increased as percentage of the combustible materials increased.

Hydraulic Actuators with Autonomous Hydraulic Supply for the Mainline Aircrafts

Directory of Open Access Journals (Sweden)

I. S. Shumilov

2014-01-01

Full Text Available Applied in the aircraft control systems, hydraulic servo actuators with autonomous hydraulic supply, so-called, hydraulic actuators of integrated configuration, i.e. combination of a source of hydraulic power and its load in the single unit, are aimed at increasing control system reliability both owing to elimination of the pipelines connecting the actuator to the hydraulic supply source, and owing to avoidance of influence of other loads failure on the actuator operability. Their purpose is also to raise control system survivability by eliminating the long pipeline communications and their replacing for the electro-conductive power supply system, thus reducing the vulnerability of systems. The main reason for a delayed application of the hydraulic actuators in the cutting-edge aircrafts was that such aircrafts require hydraulic actuators of considerably higher power with considerable heat releases, which caused an unacceptable overheat of the hydraulic actuators. Positive and negative sides of the hydraulic actuators, their alternative options of increased reliability and survivability, local hydraulic systems as an advanced alternative to independent hydraulic actuators are considered.Now to use hydraulic actuators in mainline aircrafts is inexpedient since there are the unfairly large number of the problems reducing, first and last, safety of flights, with no essential weight and operational advantages. Still works to create competitive hydraulic actuators ought to be continued.Application of local hydraulic systems (LHS will allow us to reduce length of pressure head and drain pipelines and mass of pipelines, as well as to raise their general fail-safety and survivability. Application of the LHS principle will allow us to use a majority of steering drive advantages. It is necessary to allocate especially the following:- ease of meeting requirements for the non-local spread of the engine weight;- essentially reducing length and weight of

Development of a Self-Sluicing Pressure Leaf Filter

Science.gov (United States)

Cousineau, Bernard L.; Lumsden, J. R.

The cylindrical Kelly filter presses installed in the Ewarton Works "C" phase did not perform satisfactorily because of difficulties with head seals, locking rings, and shell retraction mechanisms. As rectification required major modifications, a concept of a press which did not require to be opened for sluicing was proposed. Test work of various sluicing and res lurrying spray arrangements was carried out, and this led to the design of a self-sluicing press which used the shell of an existing Kelly press with its main axis vertical. One press was converted by July 1972, and a development period started. Although initial operation was encouraging, effective sluicing could not be guaranteed after 30 shifts. Modifications to leaf spacing, spray rotational speed, spray slot width, feed pressure and pre-coat control by November 1973, however, allowed effective performance for all of the 800 hour canvas life. Advantages are: reduced operating and maintenance manpower, clean environment, and reduced maintenance cost. The use of 1st wash overflow for sluicing has reduced caustic soda and canvas consumption. Ewarton Works now has four converted self-sluicing presses, and arc converting five more, and Arvida Works plan the installation of one for tests on red pressing (blow-off filtration). A side benefit of the development was the study of the benefits of constant pressure overflow filtration.

Calibration of hydrodynamic behavior and biokinetics for TOC removal modeling in biofilm reactors under different hydraulic conditions.

Science.gov (United States)

Zeng, Ming; Soric, Audrey; Roche, Nicolas

2013-09-01

In this study, total organic carbon (TOC) biodegradation was simulated by GPS-X software in biofilm reactors with carriers of plastic rings and glass beads under different hydraulic conditions. Hydrodynamic model by retention time distribution and biokinetic measurement by in-situ batch test served as two significant parts of model calibration. Experimental results showed that TOC removal efficiency was stable in both media due to the enough height of column, although the actual hydraulic volume changed during the variation of hydraulic condition. Simulated TOC removal efficiencies were close to experimental ones with low theil inequality coefficient values (below 0.15). Compared with glass beads, more TOC was removed in the filter with plastic rings due to the larger actual hydraulic volume and lower half saturation coefficient in spite of its lower maximum specific growth rate of biofilm, which highlighted the importance of calibrating hydrodynamic behavior and biokinetics. Copyright © 2013 Elsevier Ltd. All rights reserved.

Hydraulic turbines

International Nuclear Information System (INIS)

Meluk O, G.

1998-01-01

The hydraulic turbines are defined according to the specific speed, in impulse turbines and in reaction turbines. Currently, the Pelton turbines (of impulse) and the Francis and Kaplan turbines (of reaction), they are the most important machines in the hydroelectric generation. The hydraulic turbines are capable of generating in short times, large powers, from its loads zero until the total load and reject the load instantly without producing damages in the operation. When the hydraulic resources are important, the hydraulic turbines are converted in the axle of the electric system. Its combination with thermoelectric generation systems, it allow the continuing supply of the variations in demand of energy system. The available hydraulic resource in Colombia is of 93085 MW, of which solely 9% is exploited, become 79% of all the electrical country generation, 21% remaining is provided by means of the thermoelectric generation

The impact of mass flow and masking on the pressure drop of air filter in heavy-duty diesel engine

Directory of Open Access Journals (Sweden)

Gorji-Bandpy Mofid

2012-04-01

Full Text Available This paper presents a computational fluid dynamics (CFD calculation approach to predict and evaluate the impact of the mass-flow inlet on the pressure drop of turbocharger`s air filtfer in heavy-duty diesel engine. The numerical computations were carried out using a commercial CFD program whereas the inlet area of the air filter consisted of several holes connected to a channel. After entering through the channel, the air passes among the holes and enters the air filter. The effect of masking holes and hydraulic diameter is studied and investigated on pressure drop. The results indicate that pressure drop increase with decreasing of hydraulic diameter and masking of the holes has considerable affect on the pressure drop.

Smashing WordPress Themes Making WordPress Beautiful

CERN Document Server

Hedengren, Thord Daniel

2011-01-01

The ultimate guide to WordPress Themes - one of the hottest topics on the web today WordPress is so much more than a blogging platform, and Smashing WordPress Themes teaches readers how to make it look any way they like - from a corporate site, to a photography gallery and moreWordPress is one of the hottest tools on the web today and is used by sites including The New York Times, Rolling Stone, flickr, CNN, NASA and of course Smashing MagazineBeautiful full colour throughout - web designers expect nothing lessSmashing Magazine will fully support this book by by promoting it through their webs

Modeling and stability of electro-hydraulic servo of hydraulic excavator

Science.gov (United States)

Jia, Wenhua; Yin, Chenbo; Li, Guo; Sun, Menghui

2017-11-01

The condition of the hydraulic excavator is complicated and the working environment is bad. The safety and stability of the control system is influenced by the external factors. This paper selects hydraulic excavator electro-hydraulic servo system as the research object. A mathematical model and simulation model using AMESIM of servo system is established. Then the pressure and flow characteristics are analyzed. The design and optimization of electro-hydraulic servo system and its application in engineering machinery is provided.

RELATIONSHIP BETWEEN COMPACTING PRESSURE AND CONDITIONS IN PRESSING CHAMBER DURING BIOMASS PRESSING

Directory of Open Access Journals (Sweden)

Peter Križan

2016-02-01

Full Text Available In this paper, we will present the impact of the conditions in pressing chambers during the pressing of wooden briquettes. The conditions in pressing chambers can significantly impact the resulting compacting pressure required for the pressing of briquettes. In the introduction, we show which parameters of the pressing chamber during pressing can impact the resulting compacting pressure. The experiment results which are shown in this paper described the detected impact of some important pressing chamber parameters. This experiment aims to detect the pressing chamber length impact and the impact of the way of pressing. By setting the pressing conditions, we will be able to achieve the suitable resulting compacting pressure with respect to the required final briquettes quality.

Application of oxide fine-mesh electrodes composed of Sb-SnO2 for the electrochemical oxidation of Cibacron Marine FG using an SPE filter-press reactor

International Nuclear Information System (INIS)

Da Silva, Leonardo M.; Gonçalves, Ismael C.; Teles, José J.S.; Franco, Débora V.

2014-01-01

Highlights: • Oxide fine-mesh electrodes composed of Sb-SnO 2 (OFM-Sb-SnO 2 ) were fabricated and applied to the decolourisation and mineralisation of dye solutions using an SPE filter-press reactor. • An electrode mechanism was proposed for the irreversible parallel reactions comprising the oxygen evolution reaction (OER) and the electrochemical advanced oxidation process (EAOP) during the electrolysis of electrolyte-free dye solutions. • The reduction in current efficiency for the OER during the oxidation of Cibacron Marine FG (CMFG) increased the electrode stability. - Abstract: Oxide fine-mesh electrodes composed of tin dioxide doped with antimony (OFM-Sb-SnO 2 ), which had different percentages of Sb, were prepared using the thermal decomposition method on a stainless steel fine-mesh support for application in a solid polymer electrolyte (SPE) filter-press reactor. The electrochemical oxidation of Cibacron ® Marine FG (CMFG) was carried out during recirculation through a plug-flow reactor, using electrolyte-free dye solutions. An influence of the Sb content on the electrochemical oxidation of CMFG was verified. The highest combustion rate of CMFG was obtained using an electrode containing 6.57 mol% Sb. Studies were carried out as a function of the initial dye concentration (IDC) and the applied current density (j) for this particular electrode composition. It was verified that the decolourisation and mineralisation reactions were affected considerably by IDC and j. In trying to interpret the experimental findings, an electrode mechanism was proposed for the irreversible parallel reactions comprising the oxygen evolution reaction (OER) and the advanced oxidation process (EAOP). The instantaneous current efficiency (ICE) for the mineralisation reaction was calculated for the different cases using the average mass-transport coefficient () and the initial limiting current (j L 0 ) values. The energy consumption (EC) was also calculated for the

Changes in hydraulic conductivity of sand-bentonite mixtures accompanied with alkaline alteration

International Nuclear Information System (INIS)

Yamaguchi, Tetsuji; Sawaguchi, Takuma; Tsukada, Manabu; Tanaka, Tadao

2012-01-01

Document available in extended abstract form only. Montmorillonite is the main constituent of bentonite clay buffer materials in radioactive waste repositories. Highly alkaline environments induced by cement based materials are likely to alter montmorillonite, and to deteriorate the physical and/or chemical properties of the buffer materials. The deterioration may cause variation in hydraulic conductivity of the buffer and induce major uncertainties in the radionuclide migration analysis. Empirical data on the variation of hydraulic conductivity are, however, scarce mainly because the alteration of compacted buffer materials, sand-bentonite mixture specimen, is extremely slow (1). In this study, laboratory experiments were performed to observe changes in hydraulic conductivity of sand-bentonite mixtures accompanied with their alkaline alteration using NaOH based solutions at 80 - 90 deg. C. Our preliminary attempt to degrade sand-bentonite mixture by permeating alkaline solutions was unsuccessful, in which the flow rate of water became unstable. This was interpreted as an artifact due to generation and stagnation of air in the mixture specimen. The water conduction experimental apparatus was modified by removing membrane filter and leaving only sintered stainless steel filter, and by equipping the pressurizing tank with a preheater. Three types of experiments were performed afterwards. Series-1: Multi step alteration / water-conduction experiments. Two sand-bentonite mixture specimens with 50 mm in diameter, 10 mm in thickness and 1,600 kg m -3 in dry density were applied to hydraulic conductivity measurement and alkaline alteration process alternately. The mixture ratio was 1:1 in dry weight. The hydraulic conductivity was determined by permeating the specimens with 1.0 mol L -1 NaCl solution at 40 deg. C. While the specimens were immersed in Si, Al and Ca-adjusted 1.0 mol L -1 NaOH solution at 90 deg. C to allow alteration. In the final water-conduction step, the

Safety of 5 MW district heating reactor (DHR) and hydraulic dynamic pressure drive control rods

International Nuclear Information System (INIS)

Wu Yuanqiang; Wang Dazhong

1991-11-01

The principles and movement characteristic of the hydraulic dynamic pressure drive for control rods in 5 MW district heating reactor are described with stress on analysis of its effects on reactor safety features. The drive is different from electric-magnetic drive for PWR or hydraulic drive for BWR. The drive cylinder is driven by dynamic pressure. In the new drive system, the reactor coolant (water) used as actuating medium is pressed by pump, then injected into a step cylinder which is set in the reactor core. The cylinder will move step by step by controlling flow, then the cylinder drives the neutron absorber and controls nuclear reaction. The drive is characterized by simplicity in structure, high reliability, inherent safety, reduction in reactor height, economy, etc

Feasibility of electro-osmotic belt filter dewatering technology at pilot scale

CSIR Research Space (South Africa)

Snyman, HG

2000-01-01

Full Text Available -air. The technology was found as sensitive to polyelectrolyte dosages as belt presses. The performance of the electro-osmotic belt filter was sensitive to feed rate, but performed well with non-thickened waste activated sludge (0.61% solids), resulting in cake solids...

Servo-Elastic Dynamics of a Hydraulic Actuator Pitching a Blade with Large Deflections

International Nuclear Information System (INIS)

Hansen, M H; Kallesoee, B S

2007-01-01

This paper deals with the servo-elastic dynamics of a hydraulic pitch actuator acting on a largely bend wind turbine blade. The compressibility of the oil and flexibility of the hoses introduce a dynamic mode in the pitch bearing degree of freedom. This mode may obtain negative damping if the proportional gain on the actuator position error is defined too large relative to the viscous forces in the hydraulic system and the total rotational inertia of the pitch bearing degree of freedom. A simple expression for the stability limit of this proportional gain is derived for tuning the gain based on the Ziegler-Nichols method. Computed transfer functions from reference to actual pitch angles indicate that the actuator can be approximated as a low-pass filter with some appropriate limitations on pitching speed and acceleration. The structural blade model includes the geometrical coupling of edgewise bending and torsion for large flapwise deflections. This coupling is shown to introduce edgewise bending response for pitch reference oscillations around the natural frequency of the edgewise bending mode, in which frequency range the transfer function from reference to actual pitch angle cannot be modeled as a simple low-pass filter. The pitch bearing is assumed to be frictionless as a first approximation

Hydraulic design of Three Gorges right bank powerhouse turbine for improvement of hydraulic stability

International Nuclear Information System (INIS)

Shi, Q

2010-01-01

This paper presents the hydraulic design of Three Gorges Right Bank Powerhouse turbine for improvement of hydraulic stability. The technical challenges faced in the hydraulic design of the turbine are given. The method of hydraulic design for improving the hydraulic stability and particularly for eliminating the upper part load pressure pulsations is clarified. The final hydraulic design results of Three Gorges Right Bank Powerhouse turbine based on modern hydraulic design techniques are presented.

Hydraulic design of Three Gorges right bank powerhouse turbine for improvement of hydraulic stability

Energy Technology Data Exchange (ETDEWEB)

Shi, Q, E-mail: qhshi@dfem.com.c [Dong Fang Electrical Machinery Co., Ltd., DEC 188, Huanghe West Road, Deyang, 618000 (China)

2010-08-15

This paper presents the hydraulic design of Three Gorges Right Bank Powerhouse turbine for improvement of hydraulic stability. The technical challenges faced in the hydraulic design of the turbine are given. The method of hydraulic design for improving the hydraulic stability and particularly for eliminating the upper part load pressure pulsations is clarified. The final hydraulic design results of Three Gorges Right Bank Powerhouse turbine based on modern hydraulic design techniques are presented.

Different hydraulic traits of woody plants from tropical forests with contrasting soil water availability.

Science.gov (United States)

Zhu, Shi-Dan; Chen, Ya-Jun; Fu, Pei-Li; Cao, Kun-Fang

2017-11-01

In southwestern China, tropical karst forests (KF) and non-karst rain forests (NKF) have different species composition and forest structure owing to contrasting soil water availability, but with a few species that occur in both forests. Plant hydraulic traits are important for understanding the species' distribution patterns in these two forest types, but related studies are rare. In this study, we investigated hydraulic conductivity, vulnerability to drought-induced cavitation and wood anatomy of 23 abundant and typical woody species from a KF and a neighboring NKF, as well as two Bauhinia liana species common to both forests. We found that the KF species tended to have higher sapwood density, smaller vessel diameter, lower specific hydraulic conductivity (ks) and leaf to sapwood area ratio, and were more resistant to cavitation than NKF species. Across the 23 species distinctly occurring in either KF or NKF, there was a significant tradeoff between hydraulic efficiency and safety, which might be an underlying mechanism for distributions of these species across the two forests. Interestingly, by possessing rather large and long vessels, the two Bauhinia liana species had extremely high ks but were also high resistance to cavitation (escaping hydraulic tradeoff). This might be partially due to their distinctly dimorphic vessels, but contribute to their wide occurrence in both forests. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Performance evaluation of a dual-flow recharge filter for improving groundwater quality.

Science.gov (United States)

Samuel, Manoj P; Senthilvel, S; Mathew, Abraham C

2014-07-01

A dual-flow multimedia stormwater filter integrated with a groundwater recharge system was developed and tested for hydraulic efficiency and pollutant removal efficiency. The influent stormwater first flows horizontally through the circular layers of planted grass and biofibers. Subsequently, the flow direction changes to a vertical direction so that water moves through layers of pebbles and sand and finally gets recharged to the deep aquifers. The media in the sequence of vegetative medium:biofiber to pebble:sand were filled in nine proportions and tested for the best performing combination. Three grass species, viz., Typha (Typha angustifolia), Vetiver (Chrysopogon zizanioides), and St. Augustine grass (Stenotaphrum secundatum), were tested as the best performing vegetative medium. The adsorption behavior of Coconut (Cocos nucifera) fiber, which was filled in the middle layer, was determined by a series of column and batch studies.The dual-flow filter showed an increasing trend in hydraulic efficiency with an increase in flowrate. The chemical removal efficiency of the recharge dual-flow filter was found to be very high in case of K+ (81.6%) and Na+ (77.55%). The pH normalizing efficiency and electrical conductivity reduction efficiency were also recorded as high. The average removal percentage of Ca2+ was moderate, while that of Mg2+ was very low. The filter proportions of 1:1 to 1:2 (plant:fiber to pebble:sand) showed a superior performance compared to all other proportions. Based on the estimated annual costs and returns, all the financial viability criteria (internal rate of return, net present value, and benefit-cost ratio) were found to be favorable and affordable to farmers in terms of investing in the developed filtration system.

WordPress Bible

CERN Document Server

Brazell, Aaron

2010-01-01

The WordPress Bible provides a complete and thorough guide to the largest self hosted blogging tool. This guide starts by covering the basics of WordPress such as installing and the principles of blogging, marketing and social media interaction, but then quickly ramps the reader up to more intermediate to advanced level topics such as plugins, WordPress Loop, themes and templates, custom fields, caching, security and more. The WordPress Bible is the only complete resource one needs to learning WordPress from beginning to end.

Ex-PRESS glaucoma filter: an MRI compatible metallic orbital foreign body imaged at 1.5 and 3 T

International Nuclear Information System (INIS)

Mabray, M.C.; Uzelac, A.; Talbott, J.F.; Lin, S.C.; Gean, A.D.

2015-01-01

Aim: To report on the MRI compatibility of the Ex-PRESS glaucoma filtration device, a tiny metallic implant placed into the anterior chamber of the eye that is much smaller than traditional glaucoma shunts, and to educate the radiology community regarding its appearance. Materials and methods: Seven patients with Ex-PRESS glaucoma filtration devices were identified that had undergone MRI at San Francisco General Hospital/University of California San Francisco Medical Center by searching and cross-referencing the radiology reporting system and the electronic medical record. MRI images were reviewed for artefact interfering with interpretation. Ophthalmology examinations were reviewed for evidence of complications. Results: Eighteen individual MRI examinations were performed during 12 unique MRI events on these 7 patients. 13/18 individual MRI examinations and 7/12 MRI events were performed at 3 T with the others performed at 1.5 T. Mean time from Ex-PRESS implantation to MRI was 17.5 months. Mean time from MRI to first ophthalmology examination was 1.1 months and from MRI to latest ophthalmology examination was 6.6 months. Susceptibility artefact did not interfere with image interpretation and no complications related to MRI were encountered. Conclusion: The Ex-PRESS glaucoma filtration device appears to be safe for MRI at 1.5 and 3 T and does not produce significant susceptibility artefact to affect diagnostic interpretation adversely. - Highlights: • The Ex-PRESS glaucoma filtration device is a tiny metallic orbital implant. • It can simulate a metallic orbital foreign body on imaging. • There is little information in the literature about it's MRI safety. • We report 18 MRIs performed on 7 patients including the first at 3 T. • Imaging appears to be safe at 1.5 and 3 T in patients with this device

Robust Control of Industrial Hydraulic Cylinder Drives - with Special Reference to Sliding Mode- & Finite-Time Control

DEFF Research Database (Denmark)

Schmidt, Lasse

In industry, performance requirements regarding machinery, applications etc., are constantly increasing, and with the development of reliable proportional flow control components to reasonable prices, the market is increasingly turning its attention toward controllable fluid power solutions....... For series produced systems such as presses etc., dedicated controls are often developed. However, the great majority of the hydraulic systems developed, are produced in limited numbers for specialized applications, and here stand alone economically feasible digital controllers with ease-of-use interfaces...... are widely used. Such controllers typically provide the possibility to employ traditional linear controls such as PID schemes, and variants of this, with parameters tunable via graphical user interfaces. However, due to the intrinsic nonlinearities of hydraulic systems as well as the often limited knowledge...

A multi-packer completion to measure hydraulic heads in a lightly fractured area in the Oxfordian limestone

International Nuclear Information System (INIS)

Scholz, E.; Cruchaudet, M.; Delay, J.; Piedevache, M.

2010-01-01

Document available in extended abstract form only. Andra has designed a new type of borehole completion in order to monitor simultaneously hydraulic heads. This completion is installed in a 420 m deep borehole drilled in the Oxfordian limestone formation. The borehole is located in the South-West of Andra's Underground Research Laboratory (URL) in a lightly fractured area. The multi-packer completion is built and installed by Solexperts. This device is composed of five measurement intervals isolated with rubber expandable packers and supported by stainless steel tubing. The packers are inflated with water at a pressure of 10 bars above the water pressure at that depth. Each measurement interval comprises an interval module embedding a pressure / temperature gauge connected to the interval through a filter. The gauges are connected through one cable to a data acquisition system on surface. This completion is removable. The packers can be deflated and the completion can be installed in another borehole. The packers are positioned in the EST461 borehole according to the caliper logging and the results of permeability tests. The hydraulic head measurements are compared with the local rainfall. Interval 1 (the deepest) shows a stable hydraulic head whereas intervals 2 to 5 show hydraulic head variations. The amplitude of the hydraulic head variations are closely related to the interval depth: the deepest the interval, the lowest the hydraulic head variation. Hydraulic heads in intervals 4 and 5 are similar. These intervals are probably connected. (authors)

Hydraulic Apparatus for Mechanical Testing of Nuts

Science.gov (United States)

Hinkel, Todd J.; Dean, Richard J.; Hacker, Scott C.; Harrington, Douglas W.; Salazar, Frank

2004-01-01

The figure depicts an apparatus for mechanical testing of nuts. In the original application for which the apparatus was developed, the nuts are of a frangible type designed for use with pyrotechnic devices in spacecraft applications in which there are requirements for rapid, one-time separations of structures that are bolted together. The apparatus can also be used to test nonfrangible nuts engaged without pyrotechnic devices. This apparatus was developed to replace prior testing systems that were extremely heavy and immobile and characterized by long setup times (of the order of an hour for each nut to be tested). This apparatus is mobile, and the setup for each test can now be completed in about five minutes. The apparatus can load a nut under test with a static axial force of as much as 6.8 x 10(exp 5) lb (3.0 MN) and a static moment of as much as 8.5 x 10(exp 4) lb in. (9.6 x 10(exp 3) N(raised dot)m) for a predetermined amount of time. In the case of a test of a frangible nut, the pyrotechnic devices can be exploded to break the nut while the load is applied, in which case the breakage of the nut relieves the load. The apparatus can be operated remotely for safety during an explosive test. The load-generating portion of the apparatus is driven by low-pressure compressed air; the remainder of the apparatus is driven by 110-Vac electricity. From its source, the compressed air is fed to the apparatus through a regulator and a manually operated valve. The regulated compressed air is fed to a pneumatically driven hydraulic pump, which pressurizes oil in a hydraulic cylinder, thereby causing a load to be applied via a hydraulic nut (not to be confused with the nut under test). During operation, the hydraulic pressure is correlated with the applied axial load, which is verified by use of a load cell. Prior to operation, one end of a test stud (which could be an ordinary threaded rod or bolt) is installed in the hydraulic nut. The other end of the test stud passes

Winery wastewater treatment using the land filter technique.

Science.gov (United States)

Christen, E W; Quayle, W C; Marcoux, M A; Arienzo, M; Jayawardane, N S

2010-08-01

This study outlines a new approach to the treatment of winery wastewater by application to a land FILTER (Filtration and Irrigated cropping for Land Treatment and Effluent Reuse) system. The land FILTER system was tested at a medium size rural winery crushing approximately 20,000 tonnes of grapes. The approach consisted of a preliminary treatment through a coarse screening and settling in treatment ponds, followed by application to the land FILTER planted to pasture. The land FILTER system efficiently dealt with variable volumes and nutrient loads in the wastewater. It was operated to minimize pollutant loads in the treated water (subsurface drainage) and provide adequate leaching to manage salt in the soil profile. The land FILTER system was effective in neutralizing the pH of the wastewater and removing nutrient pollutants to meet EPA discharge limits. However, suspended solids (SS) and biological oxygen demand (BOD) levels in the subsurface drainage waters slightly exceeded EPA limits for discharge. The high organic content in the wastewater initially caused some soil blockage and impeded drainage in the land FILTER site. This was addressed by reducing the hydraulic loading rate to allow increased soil drying between wastewater irrigations. The analysis of soil characteristics after the application of wastewater found that there was some potassium accumulation in the profile but sodium and nutrients decreased after wastewater application. Thus, the wastewater application and provision of subsurface drainage ensured adequate leaching, and so was adequate to avoid the risk of soil salinisation. Crown Copyright 2010. Published by Elsevier Ltd. All rights reserved.

Designing metallic iron based water filters: Light from methylene blue discoloration.

Science.gov (United States)

Btatkeu-K, B D; Tchatchueng, J B; Noubactep, C; Caré, S

2016-01-15

Available water filtration systems containing metallic iron (Fe(0) filters) are pragmatically designed. There is a lack of sound design criteria to exploit the full potential of Fe(0) filters. A science-based design relies on valuable information on processes within a Fe(0) filter, including chemical reactions, hydrodynamics and their relation to the performance of the filter. The aim of this study was to establish a simple method to evaluate the initial performance of Fe(0) filters. The differential adsorptive affinity of methylene blue (MB) onto sand and iron oxide is exploited to characterize the evolution of a Fe(0)/sand system using the pure sand system as operational reference. Five systems were investigated for more than 70 days: pure sand, pure Fe(0), Fe(0)/sand, Fe(0)/pumice and Fe(0)/sand/pumice. Individual systems were characterized by the extent of changes in pH value, iron breakthrough, MB breakthrough and hydraulic conductivity. Results showed that for MB discoloration (i) pure sand was the most efficient system, (ii) hybrid systems were more sustainable than the pure Fe(0) system, and (iii) the pores of used pumice are poorly interconnected. Characterizing the initial reactivity of Fe(0) filters using MB discoloration has introduced a powerful tool for the exploration of various aspects of filter design. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of evaluation method for hydraulic behavior in Venturi scrubber for filtered venting

International Nuclear Information System (INIS)

Horiguchi, Naoki; Nakao, Yasuhiro; Kaneko, Akiko; Abe, Yutaka; Yoshida, Hiroyuki

2016-01-01

Filtered venting systems have been installed to restart Nuclear Power Plants in Japan after Fukushima Daiichi Nuclear Disaster. Venturi scrubber is main component of one of the systems. To evaluate decontamination performance of the Venturi scrubber for filtered venting, mechanistic evaluation method for hydrodynamic behavior is important. In this paper, our objective is to develop the method. As approaches, we conducted experimental observation under adiabatic (air-water) condition, developed a numerical simulation code with one-dimensional two-fluid model and made verification and validation by comparison between these results in terms of superficial gas, static pressure, superficial liquid velocity, droplet ratio and droplet diameter in Venturi scrubber. As results, we observed the hydrodynamic behavior, developed the code and confirmed that it has capability to evaluate the parameters with following accuracy, superficial gas velocity with +30%, static pressure in throat part with +-10%, superficial liquid velocity with +-80%, droplet diameter with +-30% and droplet ratio with -50%. (author)

Fertilization with urea, ammonium and nitrate produce different effects on growth, hydraulic traits and drought tolerance in Pinus taeda seedlings.

Science.gov (United States)

Faustino, Laura I; Moretti, Ana P; Graciano, Corina

2015-10-01

Urea fertilization decreases Pinus taeda L. growth in clay soils of subtropical areas. The negative effect of urea is related to changes in some hydraulic traits, similar to those observed in plants growing under drought. The aims of this work were (i) to determine whether different sources of nitrogen applied as fertilizers produce similar changes in growth and hydraulic traits to those observed by urea fertilization and (ii) to analyze the impact of those changes in plant drought tolerance. Plants fertilized with urea, nitrate [Formula: see text] or ammonium [Formula: see text] were grown well watered or with reduced water supply. Urea and [Formula: see text] fertilization reduced plant growth and increased root hydraulic conductance scaled by root dry weight (DW). [Formula: see text] fertilization did not reduce plant growth and increased shoot hydraulic conductance and stem hydraulic conductivity. We conclude that [Formula: see text] is the ion involved in the changes linked to the negative effect of urea fertilization on P. taeda growth. [Formula: see text] fertilization does not change drought susceptibility and it produces changes in shoot hydraulic traits, therefore plants avoid the depressive effect of fertilization. Urea and [Formula: see text] fertilizers induce changes in DW and root hydraulic conductance and consequently plants are less affected by drought. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Mine drivage in hydraulic mines

Energy Technology Data Exchange (ETDEWEB)

Ehkber, B Ya

1983-09-01

From 20 to 25% of labor cost in hydraulic coal mines falls on mine drivage. Range of mine drivage is high due to the large number of shortwalls mined by hydraulic monitors. Reducing mining cost in hydraulic mines depends on lowering drivage cost by use of new drivage systems or by increasing efficiency of drivage systems used at present. The following drivage methods used in hydraulic mines are compared: heading machines with hydraulic haulage of cut rocks and coal, hydraulic monitors with hydraulic haulage, drilling and blasting with hydraulic haulage of blasted rocks. Mining and geologic conditions which influence selection of the optimum mine drivage system are analyzed. Standardized cross sections of mine roadways driven by the 3 methods are shown in schemes. Support systems used in mine roadways are compared: timber supports, roof bolts, roof bolts with steel elements, and roadways driven in rocks without a support system. Heading machines (K-56MG, GPKG, 4PU, PK-3M) and hydraulic monitors (GMDTs-3M, 12GD-2) used for mine drivage are described. Data on mine drivage in hydraulic coal mines in the Kuzbass are discussed. From 40 to 46% of roadways are driven by heading machines with hydraulic haulage and from 12 to 15% by hydraulic monitors with hydraulic haulage.

Origin of bank filtered groundwater resources covering the drinking water demand of Budapest, Hungary

International Nuclear Information System (INIS)

Forizs, I.; Deak, J.

1998-01-01

The ratio of Danube water/infiltrated precipitation has been determined using stable oxygen isotope data on four parts of the protection area of the bank filtered water works supplying drinking water for Budapest, Hungary. These ratios comparing to those calculated by hydraulic modeling rarely match each other. The Danube water transit time calculated fro few wells by isotopic data are usually shorter than those determined by hydraulic modeling. The relation between the δ 18 O values and the nitrate chloride and sulfate pollutants shows that the source of the pollutants is on the island area (sewage water, agricultural activity and salt used for de-icing asphalt roads). (author)

Basic hydraulics

CERN Document Server

Smith, P D

1982-01-01

BASIC Hydraulics aims to help students both to become proficient in the BASIC programming language by actually using the language in an important field of engineering and to use computing as a means of mastering the subject of hydraulics. The book begins with a summary of the technique of computing in BASIC together with comments and listing of the main commands and statements. Subsequent chapters introduce the fundamental concepts and appropriate governing equations. Topics covered include principles of fluid mechanics; flow in pipes, pipe networks and open channels; hydraulic machinery;

"A space-time ensemble Kalman filter for state and parameter estimation of groundwater transport models"

Science.gov (United States)

Briseño, Jessica; Herrera, Graciela S.

2010-05-01

Herrera (1998) proposed a method for the optimal design of groundwater quality monitoring networks that involves space and time in a combined form. The method was applied later by Herrera et al (2001) and by Herrera and Pinder (2005). To get the estimates of the contaminant concentration being analyzed, this method uses a space-time ensemble Kalman filter, based on a stochastic flow and transport model. When the method is applied, it is important that the characteristics of the stochastic model be congruent with field data, but, in general, it is laborious to manually achieve a good match between them. For this reason, the main objective of this work is to extend the space-time ensemble Kalman filter proposed by Herrera, to estimate the hydraulic conductivity, together with hydraulic head and contaminant concentration, and its application in a synthetic example. The method has three steps: 1) Given the mean and the semivariogram of the natural logarithm of hydraulic conductivity (ln K), random realizations of this parameter are obtained through two alternatives: Gaussian simulation (SGSim) and Latin Hypercube Sampling method (LHC). 2) The stochastic model is used to produce hydraulic head (h) and contaminant (C) realizations, for each one of the conductivity realizations. With these realization the mean of ln K, h and C are obtained, for h and C, the mean is calculated in space and time, and also the cross covariance matrix h-ln K-C in space and time. The covariance matrix is obtained averaging products of the ln K, h and C realizations on the estimation points and times, and the positions and times with data of the analyzed variables. The estimation points are the positions at which estimates of ln K, h or C are gathered. In an analogous way, the estimation times are those at which estimates of any of the three variables are gathered. 3) Finally the ln K, h and C estimate are obtained using the space-time ensemble Kalman filter. The realization mean for each one

Ex-PRESS glaucoma filter: an MRI compatible metallic orbital foreign body imaged at 1.5 and 3T.

Science.gov (United States)

Mabray, M C; Uzelac, A; Talbott, J F; Lin, S C; Gean, A D

2015-05-01

To report on the MRI compatibility of the Ex-PRESS glaucoma filtration device, a tiny metallic implant placed into the anterior chamber of the eye that is much smaller than traditional glaucoma shunts, and to educate the radiology community regarding its appearance. Seven patients with Ex-PRESS glaucoma filtration devices were identified that had undergone MRI at San Francisco General Hospital/University of California San Francisco Medical Center by searching and cross-referencing the radiology reporting system and the electronic medical record. MRI images were reviewed for artefact interfering with interpretation. Ophthalmology examinations were reviewed for evidence of complications. Eighteen individual MRI examinations were performed during 12 unique MRI events on these 7 patients. 13/18 individual MRI examinations and 7/12 MRI events were performed at 3 T with the others performed at 1.5 T. Mean time from Ex-PRESS implantation to MRI was 17.5 months. Mean time from MRI to first ophthalmology examination was 1.1 months and from MRI to latest ophthalmology examination was 6.6 months. Susceptibility artefact did not interfere with image interpretation and no complications related to MRI were encountered. The Ex-PRESS glaucoma filtration device appears to be safe for MRI at 1.5 and 3 T and does not produce significant susceptibility artefact to affect diagnostic interpretation adversely. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Improving the Quality of Hot Stamping Parts with Innovative Press Technology and Inline Process Control

Science.gov (United States)

Vollmer, R.; Palm, C.

2017-09-01

The increasing number of hot stamped parts in the automotive industry is challenging different process areas. This paper presents a method how to improve the production rates over the whole life cycle of a hot forming part. In the core element of a hot forming line, the hydraulic press, mainly two processing steps are performed. Forming and quenching of the sheet metal part. In addition to the forming operation, it is inevitable to optimize the quenching condition in the bottom dead centre in order to reach a fully martensitic structure and tight geometrical tolerances of the part. Deviations in the blank thickness, tool wear, polishing of classical tools impair the quenching condition and therefore the part quality over the time. A new press and tool design has been developed to counter this effect by providing homogenous contact pressure over the whole die. Especially with a multi cavity tool, the new method is advantageous. Test series have shown that the new tool and press concept can produce parts with a blank thickness of 1.0 mm within 8.0 s cycle time. The so called PCH flex principle makes it possible to produce such high output rates under reliable conditions.

Experimental research on accelerated consolidation using filter jackets in fine oil sands tailings

Energy Technology Data Exchange (ETDEWEB)

Tol van, F.; Yao, Y.; Paaseen van, L.; Everts, B. [Delft Univ. of Technology, Delft (Netherlands). Dept. of Geotechnology

2010-07-01

This PowerPoint presentation discussed prefabricated vertical drains used to enhance the dewatering of fine oil sand tailings. Filtration tests conducted with thickened tailings on standard PVD jackets were presented. Potential clogging mechanisms included clogging of the filter jacket by particles, blinding of the jackets by filter cake, the decreased permeability of consolidated tailings around the drain, and the clogging of the filter jacket with bitumen. Polypropylene and polyester geotextiles were tested in a set-up that replicated conditions observed at 5 to 10 meters below mud level in an oil sand tailings pond. A finite strain consolidation model was used to interpret results obtained in the experimental study. The relationship between the void ratio and hydraulic conductivity was investigated. Results of the study showed that neither the bitumen nor the fines in the sludge cause serious blinding of the filter jackets during the 40 day test period. The consolidation process was adequately simulated with the finite strain consolidation model. tabs., figs.

WordPress for dummies

CERN Document Server

Sabin-Wilson, Lisa

2014-01-01

The bestselling WordPress guide, fully updated to cover the 2013 enhancements WordPress has millions of users, and this popular guide has sold more than 105,000 copies in its previous editions. With the newest releases of WordPress, author and WordPress expert Lisa Sabin-Wilson has completely updated the book to help you use and understand all the latest features. You'll learn about both the hosted WordPress.com version and the more flexible WordPress.org, which requires third-party hosting. Whether you're switching to WordPress from another blogging platform or just beginning to blog, you'll

Hydraulic manipulator research at ORNL

International Nuclear Information System (INIS)

Kress, R.L.; Jansen, J.F.; Love, L.J.

1997-01-01

Recently, task requirements have dictated that manipulator payload capacity increase to accommodate greater payloads, greater manipulator length, and larger environmental interaction forces. General tasks such as waste storage tank cleanup and facility dismantlement and decommissioning require manipulator life capacities in the range of hundreds of pounds rather than tens of pounds. To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned once again to hydraulics as a means of actuation. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem), sophisticated modeling, analysis, and control experiments are usually needed. Oak Ridge National Laboratory (ORNL) has a history of projects that incorporate hydraulics technology, including mobile robots, teleoperated manipulators, and full-scale construction equipment. In addition, to support the development and deployment of new hydraulic manipulators, ORNL has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The purpose of this article is to describe the past hydraulic manipulator developments and current hydraulic manipulator research capabilities at ORNL. Included are example experimental results from ORNL's flexible/prismatic test stand

Hydraulic manipulator research at ORNL

Energy Technology Data Exchange (ETDEWEB)

Kress, R.L.; Jansen, J.F. [Oak Ridge National Lab., TN (United States); Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States)

1997-03-01

Recently, task requirements have dictated that manipulator payload capacity increase to accommodate greater payloads, greater manipulator length, and larger environmental interaction forces. General tasks such as waste storage tank cleanup and facility dismantlement and decommissioning require manipulator life capacities in the range of hundreds of pounds rather than tens of pounds. To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned once again to hydraulics as a means of actuation. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem), sophisticated modeling, analysis, and control experiments are usually needed. Oak Ridge National Laboratory (ORNL) has a history of projects that incorporate hydraulics technology, including mobile robots, teleoperated manipulators, and full-scale construction equipment. In addition, to support the development and deployment of new hydraulic manipulators, ORNL has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The purpose of this article is to describe the past hydraulic manipulator developments and current hydraulic manipulator research capabilities at ORNL. Included are example experimental results from ORNL`s flexible/prismatic test stand.

Reciprocating pellet press

Science.gov (United States)

Jones, Charles W.

1981-04-07

A machine for pressing loose powder into pellets using a series of reciprocating motions has an interchangeable punch and die as its only accurately machines parts. The machine reciprocates horizontally between powder receiving and pressing positions. It reciprocates vertically to press, strip and release a pellet.

Press Advertising – Varieties and Sub-Varieties. Methods of Promoting the Press

OpenAIRE

Mikosz, Joanna

2016-01-01

In the text entitled “Press advertising – varieties and sub-varieties. Methods of promoting the press”, the author discusses press advertising, which is a fast developing mass-media phenomenon. Modernity has granted press advertising a high quality of print and paper, as well as Infinite possibilities of combining various promotional forms with the press. The author argues that press advertising is one of the best ways in which a company can communicate with the market. Its advantage is, abov...

Design and verification of additional filtration for the application of ecological transmission and hydraulic fluids in tractorc

Directory of Open Access Journals (Sweden)

Pavel Máchal

2013-01-01

Full Text Available This contribution presents the design and function verification of additional filtration. It is intended for the common transmission and hydraulic oil filling of tractors. The main role of this filtration concept is to ensure a high level of oil cleanness as a condition for the application of ecologic fluids in tractors. The next one is to decrease the wear of lubricated tractor components, the degradation of oil and eventually to extend the interval of oil change. The designed additional filtering is characterized by ease installation through the use of quick couplings and hoses to the external hydraulic circuit. Therefore, the filtration is suitable for various tractor types. Filter element has been designed with the filter ability 1micron and the ability to separate to 0.5 dm3 of water from oil. Function of additional filtration was verified during the 150 engine hours of tractor operation. During this time period the oil contamination was evaluated on the basis of chemical elements content such as Fe, Cu, Si, Al, Ni, Mo and Cr. The additive concentration was evaluated on the basis of chemical elements content such as Ca, P and Zn. During the test operation of tractor the concentration decrease of chemical elements reached the values 25.53 % (Fe, 23.53 % (Si, 25 % (Al and 5.5 % (Cu. The decrease of additive concentration reached only medium level (6.6 %. Therefore, the designed additional filtration doesn’t remove additives from oil. Based on the evaluation of the content of chemical elements (that representing contamination and additives, we can say that the designed filtering method is suitable for use in agricultural tractors.

Handbook of hydraulic fluid technology

CERN Document Server

Totten, George E

2011-01-01

""The Handbook of Hydraulic Fluid Technology"" serves as the foremost resource for designing hydraulic systems and for selecting hydraulic fluids used in engineering applications. Featuring new illustrations, data tables, as well as practical examples, this second edition is updated with essential information on the latest hydraulic fluids and testing methods. The detailed text facilitates unparalleled understanding of the total hydraulic system, including important hardware, fluid properties, and hydraulic lubricants. Written by worldwide experts, the book also offers a rigorous overview of h

Assessment of a water hydraulics joint for RH operations in the divertor region

International Nuclear Information System (INIS)

Dubus, G.; David, O.; Measson, Y.; Friconneau, J.P.

2007-01-01

Due to the high level of radiations, all the nominal maintenance in the divertor region of ITER will be carried out with help of robotic means. In reduced volumes, hydraulic applications can provide powerful actuators. They become an interesting technology to build a heavy duty manipulator for operations in space constrained areas. Oil hydraulics can not ensure the cleanliness level required for all maintenance operations in the vacuum vessel. Therefore, pure water hydraulics proposes a good alternative to oil and developments are today focusing on that direction. Although basic hydraulic elements like pumps, on-off valves, filters running with pure water are already available on the market, actuators are not so many and generally limited to linear motions. Fine control of the joint is achieved with help of servovalves. Today's off the shelf products are only adaptations from standard oil servovalves and are not specifically designed for water use. Operational experience for these products shows short lifetime expectancy and could not last a complete shutdown. Starting from the oil hydraulic version CEA with help of Cybernetix redesigned for water applications the elbow vane actuator of a Maestro arm, a six-degrees-of-freedom hydraulic manipulator used in decommissioning activities. In parallel with help of In-LHC, CEA developed a servovalve for water hydraulic applications that fits the space constraints of a Maestro manipulator. This prototype is a pressure-control valve. To a current input this servovalve supplies a very accurate pressure difference output instead of a flow rate in the case of flow control servovalve that are generally used in that kind of applications. The advantage is the improvement of the performances and stability of the force control loop. This paper presents the performances of the modified vane actuator and its servovalve. Both static and dynamic responses of the servovalve prototype with and without actuator are presented. Position and

The comparative study of pressing and extrusion like processes of construction ceramic products in the Metropolitan Area of Cucuta

International Nuclear Information System (INIS)

Gelves, J. F.; Monroy, R.; Sanchez, J.; Ramirez, R. P.

2013-01-01

The present work studies the principal variables of control in the manufacturing process of construction pieces of the Metropolitan Area of San Jose de Cucuta by extrusion and pressing techniques for its forming. The investigation was taken out using clayey samples of the two principal geological formations of the region where the raw material is taken for processing at an industrial level. The clayey samples milling was made by dry means as well as by moisture means and its particle size was measured. Subsequently the forming process was taken over by using an hydraulic press and extruder with vacuum system , both equipment s at laboratory scale, the pieces shaped were dry and firing between 980 degree centigrade and 1180 degree centigrade at the end of the process the tests were made to determine water absorption, contraction and mass loss at the pieces firing. The study results left to see that the extrusion technique allowed a faster vitrification for the region's clay in comparing with the pressing technique, the contractions of drying and firing are less marked on the pressing techniques with standard deviations much lower than in extrusion. (Author) 13 refs.

A NEW METHOD OF CHANNEL FRICTION INVERSION BASED ON KALMAN FILTER WITH UNKNOWN PARAMETER VECTOR

Institute of Scientific and Technical Information of China (English)

CHENG Wei-ping; MAO Gen-hai; LIU Guo-hua

2005-01-01

Channel friction is an important parameter in hydraulic analysis.A channel friction parameter inversion method based on Kalman Filter with unknown parameter vector is proposed.Numerical simulations indicate that when the number of monitoring stations exceeds a critical value, the solution is hardly affected.In addition, Kalman Filter with unknown parameter vector is effective only at unsteady state.For the nonlinear equations, computations of sensitivity matrices are time-costly.Two simplified measures can reduce computing time, but not influence the results.One is to reduce sensitivity matrix analysis time, the other is to substitute for sensitivity matrix.

WordPress For Dummies

CERN Document Server

Sabin-Wilson, Lisa

2011-01-01

The bestselling guide to WordPress, fully updated to help you get your blog going! Millions of bloggers rely on WordPress, the popular, free blogging platform. This guide covers all the features and improvements in the most up-to-date version of WordPress. Whether you are switching to WordPress from another blogging platform or just starting your first blog, you'll find the advice in this friendly guide gets you up to speed on both the free-hosted WordPress.com version and WordPress.org, which requires the purchase of web hosting services, and figure out which version is best for you. You'll b

Control rod drive hydraulic device

International Nuclear Information System (INIS)

Takekawa, Toru.

1994-01-01

The device of the present invention can reliably prevent a possible erroneous withdrawal of control rod driving mechanism when the pressure of a coolant line is increased by isolation operation of hydraulic control units upon periodical inspection for a BWR type reactor. That is, a coolant line is connected to the downstream of a hydraulic supply device. The coolant line is connected to a hydraulic control unit. A coolant hydraulic detection device and a pressure setting device are disposed to the coolant line. A closing signal line and a returning signal line are disposed, which connect the hydraulic supply device and a flow rate control valve for the hydraulic setting device. In the device of the present invention, even if pressure of supplied coolants is elevated due to isolation of hydraulic control units, the elevation of the hydraulic pressure can be prevented. Accordingly, reliability upon periodical reactor inspection can be improved. Further, the facility is simplified and the installation to an existent facility is easy. (I.S.)

Study on Characteristics of Hydraulic Servo System for Force Control of Hydraulic Robots

International Nuclear Information System (INIS)

Kim, Hyo-gon; Han, Changsoo; Lee, Jong-won; Park, Sangdeok

2015-01-01

Because a hydraulic actuator has high power and force densities, this allows the weight of the robot's limbs to be reduced. This allows for good dynamic characteristics and high energy efficiency. Thus, hydraulic actuators are used in some exoskeleton robots and quadrupedal robots that require high torque. Force control is useful for robot compliance with a user or environment. However, force control of a hydraulic robot is difficult because a hydraulic servo system is highly nonlinear from a control perspective. In this study, a nonlinear model was used to develop a simulation program for a hydraulic servo system consisting of a servo valve, transmission lines, and a cylinder. The problems and considerations with regard to the force control performance for a hydraulic servo system were investigated. A force control method using the nonlinear model was proposed, and its effect was evaluated with the simulation program

Study on Characteristics of Hydraulic Servo System for Force Control of Hydraulic Robots

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyo-gon; Han, Changsoo [Hanyang University, Seoul (Korea, Republic of); Lee, Jong-won [Korea University of Science and Technology, Seoul (Korea, Republic of); Park, Sangdeok [Korea Institute of Industrial Technology, Seoul (Korea, Republic of)

2015-02-15

Because a hydraulic actuator has high power and force densities, this allows the weight of the robot's limbs to be reduced. This allows for good dynamic characteristics and high energy efficiency. Thus, hydraulic actuators are used in some exoskeleton robots and quadrupedal robots that require high torque. Force control is useful for robot compliance with a user or environment. However, force control of a hydraulic robot is difficult because a hydraulic servo system is highly nonlinear from a control perspective. In this study, a nonlinear model was used to develop a simulation program for a hydraulic servo system consisting of a servo valve, transmission lines, and a cylinder. The problems and considerations with regard to the force control performance for a hydraulic servo system were investigated. A force control method using the nonlinear model was proposed, and its effect was evaluated with the simulation program.

WordPress Bible

CERN Document Server

Brazell, Aaron

2011-01-01

Get the latest word on the biggest self-hosted blogging tool on the marketWithin a week of the announcement of WordPress 3.0, it had been downloaded over a million times. Now you can get on the bandwagon of this popular open-source blogging tool with WordPress Bible, 2nd Edition. Whether you're a casual blogger or programming pro, this comprehensive guide covers the latest version of WordPress, from the basics through advanced application development. If you want to thoroughly learn WordPress, this is the book you need to succeed.Explores the principles of blogging, marketing, and social media

Free-piston engine-and-hydraulic pump for railway vehicles

Directory of Open Access Journals (Sweden)

A. F. Golovchuk

2013-04-01

Full Text Available Purpose. The development of the free-piston diesel engine-and-hydraulic pump for the continuously variable hydrostatical transmission of mobile power vehicles. Methodology. For a long time engine builders have been interesting in the problem of developing free piston engines, which have much bigger coefficient of efficiency (40…80%. Such engines don’t have the conversion of reciprocating motion for inner combustion engine piston into rotating motion of crankshaft, from which the engine torque is transferred to the power machine transmission. Free-piston engines of inner combustion don’t have the crank mechanism (CM that significantly reduces mechanical losses for friction. Such engines can be used as compressors. Free-piston engine compressor (FPEC – is a free-piston machine in which energy received from engine’s cylinder is being transferred direct to compressor’s pistons connected with operational pistons of engine without crank mechanism. Part of the pressed air is being consumed for engine cylinder drain and the other part is going to the consumer. Findings. The use of free-piston engines-and-hydraulic pumps as power-transmission plants of power vehicles (diesel locomotives, combine harvester, tractors, cars and other mobile and stationary power installations with the continuously variable transmissions allows cost effectiveness improvement and metal consumption reduction of these vehicles, since the cost effectiveness of FPE is higher by 25-30%, and the metal consumption is lower by 40-50%. Originality. One of the important advantages of the free-piston engines is their simplicity and engine balance. As a result of the crank mechanism absence their construction is much simplified and the vibrations, peculiar to the ordinary engines are eliminated. In such installation the engine pistons are directly connected through the rod to compressor pistons and therefore there are no losses in the bearing bushes. Practical value. The free

Hydraulic fracture propagation modeling and data-based fracture identification

Science.gov (United States)

Zhou, Jing

Successful shale gas and tight oil production is enabled by the engineering innovation of horizontal drilling and hydraulic fracturing. Hydraulically induced fractures will most likely deviate from the bi-wing planar pattern and generate complex fracture networks due to mechanical interactions and reservoir heterogeneity, both of which render the conventional fracture simulators insufficient to characterize the fractured reservoir. Moreover, in reservoirs with ultra-low permeability, the natural fractures are widely distributed, which will result in hydraulic fractures branching and merging at the interface and consequently lead to the creation of more complex fracture networks. Thus, developing a reliable hydraulic fracturing simulator, including both mechanical interaction and fluid flow, is critical in maximizing hydrocarbon recovery and optimizing fracture/well design and completion strategy in multistage horizontal wells. A novel fully coupled reservoir flow and geomechanics model based on the dual-lattice system is developed to simulate multiple nonplanar fractures' propagation in both homogeneous and heterogeneous reservoirs with or without pre-existing natural fractures. Initiation, growth, and coalescence of the microcracks will lead to the generation of macroscopic fractures, which is explicitly mimicked by failure and removal of bonds between particles from the discrete element network. This physics-based modeling approach leads to realistic fracture patterns without using the empirical rock failure and fracture propagation criteria required in conventional continuum methods. Based on this model, a sensitivity study is performed to investigate the effects of perforation spacing, in-situ stress anisotropy, rock properties (Young's modulus, Poisson's ratio, and compressive strength), fluid properties, and natural fracture properties on hydraulic fracture propagation. In addition, since reservoirs are buried thousands of feet below the surface, the

Testing Of The Dual Rotary Filter System

International Nuclear Information System (INIS)

Herman, D.; Fowley, M.; Stefanko, D.

2011-01-01

The Savannah River National Laboratory (SRNL) installed and tested two hydraulically connected SpinTek rotary microfilter (RMF) units to determine the behavior of a multiple filter system. Both units were successfully controlled by a control scheme written in DELTA-V architecture by Savannah River Remediation (SRR) Process Control Engineering personnel. The control system was tuned to provide satisfactory response to changing conditions during the operation of the multi-filter system. Stability was maintained through the startup and shutdown of one of the filter units while the second was still in operation. The installation configuration originally proposed by the Small Colum Ion Exchange (SCIX) project of independent filter and motor mountings may be susceptible to vibration. Significant stiffening of the filter and motor mounts was required to minimize the vibration. Alignment of the motor to the filter was a challenge in this test configuration. The deployment configuration must be easy to manipulate and allow for fine adjustment. An analysis of the vibration signature of the test system identified critical speeds. Whether it corresponds to the resonance frequency of a rotor radial vibration mode that was excited by rotor unbalance is uncertain based upon the measurements. A relative motion series should be completed on the filter with the final shaft configuration to determine if the resonances exist in the final filter design. The instrumentation selected for deployment, including the concentrate discharge control valve and flow meters, performed well. Automation of the valve control integrated well with the control scheme and when used in concert with the other control variables, allowed automated control of the dual RMF system. The one area of concern with the instrumentation was the condition resulting when the filtrate flow meter operated with less than three gpm. This low flow was at the lower range of performance for the flow meter. This should not be

TESTING OF THE DUAL ROTARY FILTER SYSTEM

Energy Technology Data Exchange (ETDEWEB)

Herman, D.; Fowley, M.; Stefanko, D.

2011-08-29

The Savannah River National Laboratory (SRNL) installed and tested two hydraulically connected SpinTek rotary microfilter (RMF) units to determine the behavior of a multiple filter system. Both units were successfully controlled by a control scheme written in DELTA-V architecture by Savannah River Remediation (SRR) Process Control Engineering personnel. The control system was tuned to provide satisfactory response to changing conditions during the operation of the multi-filter system. Stability was maintained through the startup and shutdown of one of the filter units while the second was still in operation. The installation configuration originally proposed by the Small Colum Ion Exchange (SCIX) project of independent filter and motor mountings may be susceptible to vibration. Significant stiffening of the filter and motor mounts was required to minimize the vibration. Alignment of the motor to the filter was a challenge in this test configuration. The deployment configuration must be easy to manipulate and allow for fine adjustment. An analysis of the vibration signature of the test system identified critical speeds. Whether it corresponds to the resonance frequency of a rotor radial vibration mode that was excited by rotor unbalance is uncertain based upon the measurements. A relative motion series should be completed on the filter with the final shaft configuration to determine if the resonances exist in the final filter design. The instrumentation selected for deployment, including the concentrate discharge control valve and flow meters, performed well. Automation of the valve control integrated well with the control scheme and when used in concert with the other control variables, allowed automated control of the dual RMF system. The one area of concern with the instrumentation was the condition resulting when the filtrate flow meter operated with less than three gpm. This low flow was at the lower range of performance for the flow meter. This should not be

Hydraulic Hybrid Vehicles

Science.gov (United States)

EPA and the United Parcel Service (UPS) have developed a hydraulic hybrid delivery vehicle to explore and demonstrate the environmental benefits of the hydraulic hybrid for urban pick-up and delivery fleets.

A novel control technique for active shunt power filters for aircraft applications

OpenAIRE

Lavopa, Elisabetta

2011-01-01

The More Electric Aircraft is a technological trend in modern aerospace industry to increasingly use electrical power on board the aircraft in place of mechanical, hydraulic and pneumatic power to drive aircraft subsystems. This brings major changes to the aircraft electrical system, increasing the complexity of the network topology together with stability and power quality issues. Shunt active power filters are a viable solution for power quality enhancement, in order to comply with the stan...

The hydraulic wheel

International Nuclear Information System (INIS)

Alvarez Cardona, A.

1985-01-01

The present article this dedicated to recover a technology that key in disuse for the appearance of other techniques. It is the hydraulic wheel with their multiple possibilities to use their energy mechanical rotational in direct form or to generate electricity directly in the fields in the place and to avoid the high cost of transport and transformation. The basic theory is described that consists in: the power of the currents of water and the hydraulic receivers. The power of the currents is determined knowing the flow and east knowing the section of the flow and its speed; they are given you formulate to know these and direct mensuration methods by means of floodgates, drains and jumps of water. The hydraulic receivers or properly this hydraulic wheels that are the machines in those that the water acts like main force and they are designed to transmit the biggest proportion possible of absolute work of the water, the hydraulic wheels of horizontal axis are the common and they are divided in: you rotate with water for under, you rotate with side water and wheels with water for above. It is analyzed each one of them, their components are described; the conditions that should complete to produce a certain power and formulate them to calculate it. There are 25 descriptive figures of the different hydraulic wheels

Denitrifying woodchip bioreactor and phosphorus filter pairing to minimize pollution swapping.

Science.gov (United States)

Christianson, Laura E; Lepine, Christine; Sibrell, Philip L; Penn, Chad; Summerfelt, Steven T

2017-09-15

Pairing denitrifying woodchip bioreactors and phosphorus-sorbing filters provides a unique, engineered approach for dual nutrient removal from waters impaired with both nitrogen (N) and phosphorus (P). This column study aimed to test placement of two P-filter media (acid mine drainage treatment residuals and steel slag) relative to a denitrifying system to maximize N and P removal and minimize pollution swapping under varying flow conditions (i.e., woodchip column hydraulic retention times (HRTs) of 7.2, 18, and 51 h; P-filter HRTs of 7.6-59 min). Woodchip denitrification columns were placed either upstream or downstream of P-filters filled with either medium. The configuration with woodchip denitrifying systems placed upstream of the P-filters generally provided optimized dissolved P removal efficiencies and removal rates. The P-filters placed upstream of the woodchip columns exhibited better P removal than downstream-placed P-filters only under overly long (i.e., N-limited) retention times when highly reduced effluent exited the woodchip bioreactors. The paired configurations using mine drainage residuals provided significantly greater P removal than the steel slag P-filters (e.g., 25-133 versus 8.8-48 g P removed m -3 filter media d -1 , respectively), but there were no significant differences in N removal between treatments (removal rates: 8.0-18 g N removed m -3 woodchips d -1 ; N removal efficiencies: 18-95% across all HRTs). The range of HRTs tested here resulted in various undesirable pollution swapping by-products from the denitrifying bioreactors: nitrite production when nitrate removal was not complete and sulfate reduction, chemical oxygen demand production and decreased pH during overly long retention times. The downstream P-filter placement provided a polishing step for removal of chemical oxygen demand and nitrite. Copyright © 2017 The Conservation Fund. Published by Elsevier Ltd.. All rights reserved.

Denitrifying woodchip bioreactor and phosphorus filter pairing to minimize pollution swapping

Science.gov (United States)

Christianson, Laura E.; Lepine, Christine; Sibrell, Philip; Penn, Chad J.; Summerfelt, Steven T.

2017-01-01

Pairing denitrifying woodchip bioreactors and phosphorus-sorbing filters provides a unique, engineered approach for dual nutrient removal from waters impaired with both nitrogen (N) and phosphorus (P). This column study aimed to test placement of two P-filter media (acid mine drainage treatment residuals and steel slag) relative to a denitrifying system to maximize N and P removal and minimize pollution swapping under varying flow conditions (i.e., woodchip column hydraulic retention times (HRTs) of 7.2, 18, and 51 h; P-filter HRTs of 7.6–59 min). Woodchip denitrification columns were placed either upstream or downstream of P-filters filled with either medium. The configuration with woodchip denitrifying systems placed upstream of the P-filters generally provided optimized dissolved P removal efficiencies and removal rates. The P-filters placed upstream of the woodchip columns exhibited better P removal than downstream-placed P-filters only under overly long (i.e., N-limited) retention times when highly reduced effluent exited the woodchip bioreactors. The paired configurations using mine drainage residuals provided significantly greater P removal than the steel slag P-filters (e.g., 25–133 versus 8.8–48 g P removed m−3 filter media d−1, respectively), but there were no significant differences in N removal between treatments (removal rates: 8.0–18 g N removed m−3 woodchips d−1; N removal efficiencies: 18–95% across all HRTs). The range of HRTs tested here resulted in various undesirable pollution swapping by-products from the denitrifying bioreactors: nitrite production when nitrate removal was not complete and sulfate reduction, chemical oxygen demand production and decreased pH during overly long retention times. The downstream P-filter placement provided a polishing step for removal of chemical oxygen demand and nitrite.

Corneal decompensation following filtering surgery with the Ex-PRESS® mini glaucoma shunt device

Directory of Open Access Journals (Sweden)

Tojo N

2015-03-01

Full Text Available Naoki Tojo, Atsushi Hayashi, Akio Miyakoshi Department of Ophthalmology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan Purpose: To report a case of corneal decompensation due to the Ex-PRESS® mini glaucoma shunt device (Ex-PRESS.Patient and methods: A 75-year-old man had pseudoexfoliation glaucoma in his right eye. He underwent filtration surgery with Ex-PRESS. His intraocular pressure was 7 mmHg after 9 months.Results: We observed partial decompensation of the corneal endothelium adjacent to the filtering bleb. Specular microscopy revealed a marked decrease in the endothelial cell density at the center of the cornea.Conclusion: Anterior segment optical coherence tomography is very useful for evaluating corneal edema and the position of Ex-PRESS. It is important to follow up with an examination of the corneal endothelial cells. Keywords: Ex-PRESS, bullous keratopathy, trabeculectomy, complication, cornea 

Numerical modelling of the erosion and deposition of sand inside a filter layer

DEFF Research Database (Denmark)

Jacobsen, Niels Gjøl; van Gent, Marcel R. A.; Fredsøe, Jørgen

2017-01-01

This paper treats the numerical modelling of the behaviour of a sand core covered by rocks and exposed to waves. The associated displacement of the rock is also studied. A design that allows for erosion and deposition of the sand core beneath a rock layer in a coastal structure requires an accurate...... prediction method to assure that the amount of erosion remains within acceptable limits. This work presents a numerical model that is capable of describing the erosion and deposition patterns inside of an open filter of rock on top of sand. The hydraulic loading is that of incident irregular waves...... and the open filters are surface piercing. Due to the few experimental data sets on sediment transport inside of rock layers, a sediment transport formulation has been proposed based on a matching between the numerical model and experimental data on the profile deformation inside an open filter. The rock layer...

Water Hydraulic Systems

DEFF Research Database (Denmark)

Conrad, Finn

2005-01-01

The paper presents research results using IT-Tools for CAD and dynamic modelling, simulation, analysis, and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. Matlab/Simulink and CATIA are used as IT-Tools. The contributions include results from on......-going research projects on fluid power and mechatronics based on tap water hydraulic servovalves and linear servo actuators and rotary vane actuators for motion control and power transmission. Development and design a novel water hydraulic rotary vane actuator for robot manipulators. Proposed mathematical...... modelling, control and simulation of a water hydraulic rotary vane actuator applied to power and control a two-links manipulator and evaluate performance. The results include engineering design and test of the proposed simulation models compared with IHA Tampere University’s presentation of research...

Fracking in the UK press: threat dynamics in an unfolding debate.

Science.gov (United States)

Jaspal, Rusi; Nerlich, Brigitte

2014-04-01

Shale gas is a novel source of fossil fuel which is extracted by induced hydraulic fracturing, or "fracking". This article examines the socio-political dimension of fracking as manifested in the UK press at three key temporal points in the debate on the practice. Three newspaper corpora were analysed qualitatively using Thematic Analysis and Social Representations Theory. Three overarching themes are discussed: "April-May 2011: from Optimism to Scepticism"; "November 2011: (De-) Constructing and Re-Constructing Risk and Danger"; "April 2012: consolidating Social Representations of Fracking". In this article, we examine the emergence of and inter-relations between competing social representations, discuss the dynamics of threat positioning and show how threat can be re-construed in order to serve particular socio-political ends in the debate on fracking.

Characteristic Length Scales in Fracture Networks: Hydraulic Connectivity through Periodic Hydraulic Tests

Science.gov (United States)

Becker, M.; Bour, O.; Le Borgne, T.; Longuevergne, L.; Lavenant, N.; Cole, M. C.; Guiheneuf, N.

2017-12-01

Determining hydraulic and transport connectivity in fractured bedrock has long been an important objective in contaminant hydrogeology, petroleum engineering, and geothermal operations. A persistent obstacle to making this determination is that the characteristic length scale is nearly impossible to determine in sparsely fractured networks. Both flow and transport occur through an unknown structure of interconnected fracture and/or fracture zones making the actual length that water or solutes travel undetermined. This poses difficulties for flow and transport models. For, example, hydraulic equations require a separation distance between pumping and observation well to determine hydraulic parameters. When wells pairs are close, the structure of the network can influence the interpretation of well separation and the flow dimension of the tested system. This issue is explored using hydraulic tests conducted in a shallow fractured crystalline rock. Periodic (oscillatory) slug tests were performed at the Ploemeur fractured rock test site located in Brittany, France. Hydraulic connectivity was examined between three zones in one well and four zones in another, located 6 m apart in map view. The wells are sufficiently close, however, that the tangential distance between the tested zones ranges between 6 and 30 m. Using standard periodic formulations of radial flow, estimates of storativity scale inversely with the square of the separation distance and hydraulic diffusivity directly with the square of the separation distance. Uncertainty in the connection paths between the two wells leads to an order of magnitude uncertainty in estimates of storativity and hydraulic diffusivity, although estimates of transmissivity are unaffected. The assumed flow dimension results in alternative estimates of hydraulic parameters. In general, one is faced with the prospect of assuming the hydraulic parameter and inverting the separation distance, or vice versa. Similar uncertainties exist

Assessing clustering strategies for Gaussian mixture filtering a subsurface contaminant model

KAUST Repository

Liu, Bo

2016-02-03

An ensemble-based Gaussian mixture (GM) filtering framework is studied in this paper in term of its dependence on the choice of the clustering method to construct the GM. In this approach, a number of particles sampled from the posterior distribution are first integrated forward with the dynamical model for forecasting. A GM representation of the forecast distribution is then constructed from the forecast particles. Once an observation becomes available, the forecast GM is updated according to Bayes’ rule. This leads to (i) a Kalman filter-like update of the particles, and (ii) a Particle filter-like update of their weights, generalizing the ensemble Kalman filter update to non-Gaussian distributions. We focus on investigating the impact of the clustering strategy on the behavior of the filter. Three different clustering methods for constructing the prior GM are considered: (i) a standard kernel density estimation, (ii) clustering with a specified mixture component size, and (iii) adaptive clustering (with a variable GM size). Numerical experiments are performed using a two-dimensional reactive contaminant transport model in which the contaminant concentration and the heterogenous hydraulic conductivity fields are estimated within a confined aquifer using solute concentration data. The experimental results suggest that the performance of the GM filter is sensitive to the choice of the GM model. In particular, increasing the size of the GM does not necessarily result in improved performances. In this respect, the best results are obtained with the proposed adaptive clustering scheme.

BWR 9 X 9 Fuel Assembly Thermal-Hydraulic Tests (2): Hydraulic Vibration Test

International Nuclear Information System (INIS)

Yoshiaki Tsukuda; Katsuichiro Kamimura; Toshiitsu Hattori; Akira Tanabe; Noboru Saito; Masahiko Warashina; Yuji Nishino

2002-01-01

Nuclear Power Engineering Corporation (NUPEC) conducted thermal-hydraulic projects for verification of thermal-hydraulic design reliability for BWR high-burnup 8 x 8 and 9 x 9 fuel assemblies, entrusted by the Ministry of Economy, Trade and Industry (METI). As a part of the NUPEC thermal-hydraulic projects, hydraulic vibration tests using full-scale test assemblies simulating 9 x 9 fuel assemblies were carried out to evaluate BWR fuel integrity. The test data were applied to development of a new correlation for the estimation of fuel rod vibration amplitude. (authors)

News/Press Releases

Data.gov (United States)

Office of Personnel Management — A press release, news release, media release, press statement is written communication directed at members of the news media for the purpose of announcing programs...

Head First WordPress

CERN Document Server

Siarto, Jeff

2010-01-01

Whether you're promoting your business or writing about your travel adventures, Head First WordPress will teach you not only how to make your blog look unique and attention-grabbing, but also how to dig into the more complex features of WordPress 3.0 to make your website work well, too. You'll learn how to move beyond the standard WordPress look and feel by customizing your blog with your own URL, templates, plugin functionality, and more. As you learn, you'll be working with real WordPress files: The book's website provides pre-fab WordPress themes to download and work with as you follow al

WordPress multisite administration

CERN Document Server

Longren, Tyler

2013-01-01

This is a simple, concise guide with a step-by-step approach, packed with screenshots and examples to set up and manage a network blog using WordPress.WordPress Multisite Administration is ideal for anyone wanting to familiarize themselves with WordPress Multisite. You'll need to know the basics about WordPress, and having at least a broad understanding of HTML, CSS, and PHP will help, but isn't required.

EFFECTIVE APPLICATIO N OF LIDAR DATA IN T WO - DIMENSIONAL HYDRAULIC MODELLING

Directory of Open Access Journals (Sweden)

Bakuła Krzysztof

2014-12-01

Full Text Available This paper presents aspects of ALS data usage in two - dimensional hydraulic modelling including generation of high - precision digital terrain models, t heir effective processing which is a compromise between the resolution and the accuracy of the processed data, as well as information about the roughness of the land cover providing information that could compete with information from topographic databases and orthophotomaps. Still evolving ALS technology makes it possible to collect the data with constantly increasing spatial resolution that guarantees correct representation of the terrain shape and height. It also provides a reliable description of the la nd cover. However, the size of generated files may cause roblems in their effective usage in the 2D hydraulic modeling where Saint - Venant’s equations are implemented. High - resolution elevation models make it impossible or prolong the duration of the calcu lations for large areas in complex algorithms defining a model of the water movement, which is directly related to the cost of the hydraulic analysis. As far as an effective usage of voluminous datasets is concerned, the data reduction is recommended. Suc h a process should reduce the size of the data files, maintain their accuracy and keep the appropriate structure to allow their further application in the hydraulic modelling. An application of only a few percent of unprocessed datasets, selected with the use of specified filtering algorithms and spatial analysis tools, can give the same result of the hydraulic modeling obtained in a significantly shorter time than the result of the comparable operation on unprocessed datasets. Such an approach, however, is not commonly used, which means the most reliable hydraulic models are applied only in small areas in the largest cities. Another application of ALS data is its potential usage in digital roughness model creation for 2D hydraulic models. There are many po ssibilities of roughness

Enhancement of CNT-based filters efficiency by ion beam irradiation

Science.gov (United States)

Elsehly, Emad M.; Chechenin, N. G.; Makunin, A. V.; Shemukhin, A. A.; Motaweh, H. A.

2018-05-01

It is shown in the report that disorder produced by ion beam irradiation can enhance the functionality of the carbon nanotubes. The filters of pressed multiwalled carbon nanotubes (MWNTs) were irradiated by He+ ions of the energy E = 80 keV with the fluence 2 × 1016 ion/cm2. The removal of manganese from aqueous solutions by using pristine and ion beam irradiated MWNTs filters was studied as a function of pH, initial concentration of manganese in aqueous solution, MWNT mass and contact time. The filters before and after filtration were characterized by Raman (RS) and energy dispersive X-ray spectroscopy (EDS) techniques to investigate the deposition content in the filter and defect formation in the MWNTs. The irradiated samples showed an enhancement of removal efficiency of manganese up to 97.5% for 10 ppm Mn concentration, suggesting that irradiated MWNT filter is a better Mn adsorbent from aqueous solutions than the pristine one. Radiation-induced chemical functionalization of MWNTs due to ion beam irradiation, suggesting that complexation between the irradiated MWNTs and manganese ions is another mechanism. This conclusion is supported by EDS and RS and is correlated with a larger disorder in the irradiated samples as follows from RS. The study demonstrates that ion beam irradiation is a promising tool to enhance the filtration efficiency of MWNT filters.

A Robust Control Concept for Hydraulic Drives Based on Second Order Sliding Mode Disturbance Compensation

DEFF Research Database (Denmark)

Schmidt, Lasse; Andersen, Torben O.; Johansen, Per

2017-01-01

, the successful implementation relies heavily on the low-pass filter design where the drive dynamics, sample rate etc. play a significant role. In this paper the utilization of the super twisting algorithm for disturbance compensation is considered. The fact that the discontinuity here is nested in an integral......The application of sliding mode algorithms for control of hydraulic drives has gained increasing interest in recent years due to algorithm simplicity, low number of parameters and possible excellent control performance. Both application of firstand higher order sliding mode control algorithms...... observer based control etc., and several examples of such approaches have been presented in literature. The latter case appear especially interesting as a sliding mode actually takes place, but only the low-pass filtered sliding mode algorithm output is used in the actual control input. However...

Power Management in Mobile Hydraulic Applications - An Approach for Designing Hydraulic Power Supply Systems

DEFF Research Database (Denmark)

Pedersen, Henrik Clemmensen

2004-01-01

Throughout the last three decades energy consumption has become one of the primary design aspects in hydraulic systems, especially for mobile hydraulic systems, as power and cooling capacity here is at limited disposal. Considering the energy usage, this is dependent on component efficiency, but ...... the hydraulic power supply in the most energy efficient way, when considering a number of load situations. Finally an example of the approach is shown to prove its validity.}......Throughout the last three decades energy consumption has become one of the primary design aspects in hydraulic systems, especially for mobile hydraulic systems, as power and cooling capacity here is at limited disposal. Considering the energy usage, this is dependent on component efficiency...

Hydraulic Yaw System

DEFF Research Database (Denmark)

Stubkier, Søren; Pedersen, Henrik C.; Mørkholt, M.

a hydraulic soft yaw system, which is able to reduce the loads on the wind turbine significantly. A full scale hydraulic yaw test rig is available for experiments and tests. The test rig is presented as well as the system schematics of the hydraulic yaw system....... the HAWC2 aeroelastic code and an extended model of the NREL 5MW turbine combined with a simplified linear model of the turbine, the parameters of the soft yaw system are optimized to reduce loading in critical components. Results shows that a significant reduction in fatigue and extreme loads to the yaw...... system and rotor shaft when utilizing the soft yaw drive concept compared to the original stiff yaw system. The physical demands of the hydraulic yaw system are furthermore examined for a life time of 20 years. Based on the extrapolated loads, the duty cycles show that it is possible to construct...

Assessment of a water hydraulics joint for RH operations in the divertor region

Energy Technology Data Exchange (ETDEWEB)

Dubus, G.; David, O.; Measson, Y.; Friconneau, J.P. [CEA LIST, Interactive Robotics Unit (France)

2007-07-01

Due to the high level of radiations, all the nominal maintenance in the divertor region of ITER will be carried out with help of robotic means. In reduced volumes, hydraulic applications can provide powerful actuators. They become an interesting technology to build a heavy duty manipulator for operations in space constrained areas. Oil hydraulics can not ensure the cleanliness level required for all maintenance operations in the vacuum vessel. Therefore, pure water hydraulics proposes a good alternative to oil and developments are today focusing on that direction. Although basic hydraulic elements like pumps, on-off valves, filters running with pure water are already available on the market, actuators are not so many and generally limited to linear motions. Fine control of the joint is achieved with help of servovalves. Today's off the shelf products are only adaptations from standard oil servovalves and are not specifically designed for water use. Operational experience for these products shows short lifetime expectancy and could not last a complete shutdown. Starting from the oil hydraulic version CEA with help of Cybernetix redesigned for water applications the elbow vane actuator of a Maestro arm, a six-degrees-of-freedom hydraulic manipulator used in decommissioning activities. In parallel with help of In-LHC, CEA developed a servovalve for water hydraulic applications that fits the space constraints of a Maestro manipulator. This prototype is a pressure-control valve. To a current input this servovalve supplies a very accurate pressure difference output instead of a flow rate in the case of flow control servovalve that are generally used in that kind of applications. The advantage is the improvement of the performances and stability of the force control loop. This paper presents the performances of the modified vane actuator and its servovalve. Both static and dynamic responses of the servovalve prototype with and without actuator are presented. Position

Hydraulic lifter of a drilling unit

Energy Technology Data Exchange (ETDEWEB)

Velikovskiy, L S; Demin, A V; Shadchinov, L M

1979-01-08

The invention refers to drilling equipment, in particular, devices for lowering and lifting operations during drilling. A hydraulic lifter of the drilling unit is suggested which contains a hydraulic cylinder, pressure line and hollow plunger whose cavities are hydraulically connected. In order to improve the reliability of the hydraulic lifter by balancing the forces of compression in the plunger of the hydraulic cylinder, a closed vessel is installed inside the plunger and rigidly connected to its ends. Its cavity is hydraulically connected to the pressure line.

Vibration of hydraulic machinery

CERN Document Server

Wu, Yulin; Liu, Shuhong; Dou, Hua-Shu; Qian, Zhongdong

2013-01-01

Vibration of Hydraulic Machinery deals with the vibration problem which has significant influence on the safety and reliable operation of hydraulic machinery. It provides new achievements and the latest developments in these areas, even in the basic areas of this subject. The present book covers the fundamentals of mechanical vibration and rotordynamics as well as their main numerical models and analysis methods for the vibration prediction. The mechanical and hydraulic excitations to the vibration are analyzed, and the pressure fluctuations induced by the unsteady turbulent flow is predicted in order to obtain the unsteady loads. This book also discusses the loads, constraint conditions and the elastic and damping characters of the mechanical system, the structure dynamic analysis, the rotor dynamic analysis and the system instability of hydraulic machines, including the illustration of monitoring system for the instability and the vibration in hydraulic units. All the problems are necessary for vibration pr...

Preparation and characterization of monel (70% Ni-30% Cu) metallic filters; Preparacao e caracterizacao de filtro metalico monel (70% Ni-30% Cu)

Energy Technology Data Exchange (ETDEWEB)

Camargo Lavos, I de

1994-12-31

This work investigates a process for the fabrication and characterization of monel (Ni-Cu) filters. The powder consolidation was made by vibration or by pressing at various pressures (200, 300 e 400 MPa). The sintering was carried out at 1100{sup 0} C during 1 hour under H{sub 2} atmosphere. The filter characterization was performed by measuring its density, porosity, filtering capacity and permeability. It was obtained a correlation between the processing variables (consolidation and sintering), including powder properties, and the filters characteristics. (author). 59 refs, 41 figs, 7 tabs.

The Global University Press

Science.gov (United States)

Dougherty, Peter J.

2012-01-01

The modern world's understanding of American university press has long been shaped by university-press books. American university-press books are good international advertisements for the universities whose logos grace their spines. The growth of transnational scholarship and the expansion of digital communications networks are converging in ways…

TESTING OF THE SECOND GENERATION SPINTEK ROTARY FILTER -11357

Energy Technology Data Exchange (ETDEWEB)

Herman, D.; Poirier, M.; Fowley, M.; Keefer, M.; Huff, T.

2011-02-02

The SpinTek rotary microfilter has been developed under the Department of Energy (DOE) Office of Environmental Management (EM) for the purpose of deployment in radioactive service in the DOE complex. The unit that was fabricated and tested is the second generation of the filter that incorporates recommended improvements from previous testing. The completion of this test satisfied a key milestone for the EM technology development program and technology readiness for deployment by Savannah River Remediation in the Small Column Ion Exchange and Sludge Washing processes at the Savannah River Site (SRS). The Savannah River National Laboratory (SRNL) contracted SpinTek Filtration to fabricate a full scale 25 disk rotary filter and perform a 1000 hour endurance test with a simulated SRS sludge. Over 1500 hours of operation have been completed with the filter. SpinTek Filtration fabricated a prototypic 25 disk rotary filter including updates to manufacturing tolerances, an updated design to the rotary joint, improved cooling to the bottom journal, decreases in disk and filter shaft hydraulic resistances. The filter disks were fabricated with 0.5 {micro} pore size, sintered-metal filter media manufactured by Pall Corporation (M050). After fabrication was complete, the filter passed acceptance tests demonstrating rejection of solids and clean water flux with a 50% improvement over the previous filters. Once the acceptance test was complete, a 1000 hour endurance test was initiated simulating a sludge washing process. The test used a simulated SRS Sludge Batch 6 recipe. The insoluble solids started at 5 wt% and were raised to 10 and 15 wt% insoluble solids to simulate the concentration of a large volume tank. The filter system was automated and set up for 24 hour unattended operation. To facilitate this, process control logic was written to operate the filter. During the development it was demonstrated that the method of starting and stopping the filter can affect the build

Hydraulic Structures : Caissons

NARCIS (Netherlands)

Voorendt, M.Z.; Molenaar, W.F.; Bezuyen, K.G.

These lecture notes on caissons are part of the study material belonging to the course 'Hydraulic Structures 1' (code CTB3355), part of the Bachelor of Science education and the Hydraulic Engineering track of the Master of Science education for civil engineering students at Delft University of

Vegetation-zonation patterns across a temperate mountain cloud forest ecotone are not explained by variation in hydraulic functioning or water relations.

Science.gov (United States)

Berry, Z Carter; Johnson, Daniel M; Reinhardt, Keith

2015-09-01

sensitive indicators of hydraulic functioning in these mesic, foggy ecosystems. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Determining the Conditions for the Hydraulic Impacts Emergence at Hydraulic Systems

Directory of Open Access Journals (Sweden)

Mazurenko A.S.

2017-08-01

Full Text Available This research aim is to develop a method for modeling the conditions for the critical hydrau-lic impacts emergence on thermal and nuclear power plants’ pipeline systems pressure pumps depart-ing from the general provisions of the heat and hydrodynamic instability theory. On the developed method basis, the conditions giving rise to the reliability-critical hydraulic impacts emergence on pumps for the thermal and nuclear power plants’ typical pipeline system have been determined. With the flow characteristic minimum allowable (critical sensitivity, the flow velocity fluctuations ampli-tude reaches critical values at which the pumps working elements’ failure occurs. The critical hydrau-lic impacts emergence corresponds to the transition of the vibrational heat-hydrodynamic instability into an aperiodic one. As research revealed, a highly promising approach as to the preventing the criti-cal hydraulic impacts related to the foreground use of pumps having the most sensitive consumption (at supply network performance (while other technical characteristics corresponding to that parame-ter. The research novelty refers to the suggested method elaborated by the authors’ team, which, in contrast to traditional approaches, is efficient in determining the pump hydraulic impact occurrence conditions when the vibrational heat-hydrodynamic instability transition to the aperiodic instability.

Hot-pressed geopolymer

DEFF Research Database (Denmark)

Ranjbar, Navid; Mehrali, Mohammad; Maheri, Mahmoud R.

2017-01-01

This research explores the use of simultaneous heating and pressing techniques in order to enhance the mechanical properties of fly ash (FA) based geopolymer under relatively low temperature conditions to ensure minimum-porosity. Four effective parameters of pressing force, alkali activator...

Water hydraulic applications in hazardous environments

International Nuclear Information System (INIS)

Siuko, M.; Koskinen, K.T.; Vilenius, M.J.

1996-01-01

Water hydraulic technology provides several advantages for devices operating in critical environment. Though water hydraulics has traditionally been used in very rough applications, gives recent strong development of components possibility to build more sophisticated applications and devices with similar capacity and control properties than those of oil hydraulics without the disadvantages of oil hydraulic systems. In this paper, the basic principles, possibilities and advantages of water hydraulics are highlighted, some of the most important design considerations are presented and recent developments of water hydraulic technology are presented. Also one interesting application area, ITER fusion reactor remote handling devices, are discussed. (Author)

Change of Pressing Chamber Conicalness at Briquetting Process in Briquetting Machine Pressing Chamber

Directory of Open Access Journals (Sweden)

Peter Križan

2012-01-01

Full Text Available In this paper, we will present the impact of the conical shape of a pressing chamber, an important structural parameter. Besides the known impact of the technological parameters of pressing chambers, it is also very important to pay attention to their structural parameters. In the introduction, we present a theoretical analysis of pressing chamber conicalness. An experiment aimed at detecting this impact was performed at our institute, and it showed that increasing the conicalness of a pressing chamber improves the quality of the final briquettes. The conicalness of the pressing chamber has a significanteffect on the final briquette quality and on the construction of briquetting machines. The experimental findings presented here show the importance of this parameter in the briquetting process.

A Particle Smoother with Sequential Importance Resampling for soil hydraulic parameter estimation: A lysimeter experiment

Science.gov (United States)

Montzka, Carsten; Hendricks Franssen, Harrie-Jan; Moradkhani, Hamid; Pütz, Thomas; Han, Xujun; Vereecken, Harry

2013-04-01

An adequate description of soil hydraulic properties is essential for a good performance of hydrological forecasts. So far, several studies showed that data assimilation could reduce the parameter uncertainty by considering soil moisture observations. However, these observations and also the model forcings were recorded with a specific measurement error. It seems a logical step to base state updating and parameter estimation on observations made at multiple time steps, in order to reduce the influence of outliers at single time steps given measurement errors and unknown model forcings. Such outliers could result in erroneous state estimation as well as inadequate parameters. This has been one of the reasons to use a smoothing technique as implemented for Bayesian data assimilation methods such as the Ensemble Kalman Filter (i.e. Ensemble Kalman Smoother). Recently, an ensemble-based smoother has been developed for state update with a SIR particle filter. However, this method has not been used for dual state-parameter estimation. In this contribution we present a Particle Smoother with sequentially smoothing of particle weights for state and parameter resampling within a time window as opposed to the single time step data assimilation used in filtering techniques. This can be seen as an intermediate variant between a parameter estimation technique using global optimization with estimation of single parameter sets valid for the whole period, and sequential Monte Carlo techniques with estimation of parameter sets evolving from one time step to another. The aims are i) to improve the forecast of evaporation and groundwater recharge by estimating hydraulic parameters, and ii) to reduce the impact of single erroneous model inputs/observations by a smoothing method. In order to validate the performance of the proposed method in a real world application, the experiment is conducted in a lysimeter environment.

Teach yourself visually WordPress

CERN Document Server

Majure, Janet

2012-01-01

Get your blog up and running with the latest version of WordPress WordPress is one of the most popular, easy-to-use blogging platforms and allows you to create a dynamic and engaging blog, even if you have no programming skills or experience. Ideal for the visual learner, Teach Yourself VISUALLY WordPress, Second Edition introduces you to the exciting possibilities of the newest version of WordPress and helps you get started, step by step, with creating and setting up a WordPress site. Author and experienced WordPress user Janet Majure shares advice, insight, and best practices for taking full

Velocity Potential in Engineering Hydraulics versus Force Potential in Groundwater Dynamics

Science.gov (United States)

Weyer, K.

2013-12-01

required to overcome the resistance to downward flow in penetrated rocks. As one of the consequences, the engineering hydraulics concept of buoyancy forces does not comply with physics. In general the vectorial forces within gravitationally-driven flow systems are ignored when using engineering hydraulics. Scheidegger (1974, p. 79) states, however, verbatim and unequivocally: 'It is thus a force potential and not a velocity potential which governs flow through porous media' (emphasis added). This presentation will outline the proper forces for groundwater flow and their calculations based on Hubbert's force potential and additional physical insights by Weyer (1978). REFERENCES Bear, J. 1972. Dynamics of Fluids in Porous Media. American Elsevier Publishing Company, Inc., New York, NY, USA. de Marsily, G. 1986. Quantitative Hydrogeology: Groundwater Hydrology for Engineers. Academic Press, San Diego, California, USA. Hubbert, M.K. 1940. The theory of groundwater motion. Journal of Geology 48(8): 785-944. Muskat, Morris, 1937. The flow of homogeneous fluids through porous media. McGraw-Hill Book Company Inc., New York, NY, USA Scheidegger. A.E., 1974. The physics of flow through permeable media. Third Edition. University of Toronto Press, Toronto, Ontario, Canada Weyer, K.U., 1978. Hydraulic forces in permeable media. Bulletin du B.R.G.M., Vol. 91, pp. 286-297, Orléans, France.

Cradle modification for hydraulic ram

International Nuclear Information System (INIS)

Koons, B.M.

1995-01-01

The analysis of the cradle hydraulic system considers stress, weld strength, and hydraulic forces required to lift and support the cradle/pump assembly. The stress and weld strength of the cradle modifications is evaluated to ensure that they meet the requirements of the American Institute for Steel Construction (AISC 1989). The hydraulic forces are evaluated to ensure that the hydraulic system is capable of rotating the cradle and pump assembly to the vertical position (between 70 degrees and 90 degrees)

Specific storage and hydraulic conductivity tomography through the joint inversion of hydraulic heads and self-potential data

Science.gov (United States)

Ahmed, A. Soueid; Jardani, A.; Revil, A.; Dupont, J. P.

2016-03-01

Transient hydraulic tomography is used to image the heterogeneous hydraulic conductivity and specific storage fields of shallow aquifers using time series of hydraulic head data. Such ill-posed and non-unique inverse problem can be regularized using some spatial geostatistical characteristic of the two fields. In addition to hydraulic heads changes, the flow of water, during pumping tests, generates an electrical field of electrokinetic nature. These electrical field fluctuations can be passively recorded at the ground surface using a network of non-polarizing electrodes connected to a high impedance (> 10 MOhm) and sensitive (0.1 mV) voltmeter, a method known in geophysics as the self-potential method. We perform a joint inversion of the self-potential and hydraulic head data to image the hydraulic conductivity and specific storage fields. We work on a 3D synthetic confined aquifer and we use the adjoint state method to compute the sensitivities of the hydraulic parameters to the hydraulic head and self-potential data in both steady-state and transient conditions. The inverse problem is solved using the geostatistical quasi-linear algorithm framework of Kitanidis. When the number of piezometers is small, the record of the transient self-potential signals provides useful information to characterize the hydraulic conductivity and specific storage fields. These results show that the self-potential method reveals the heterogeneities of some areas of the aquifer, which could not been captured by the tomography based on the hydraulic heads alone. In our analysis, the improvement on the hydraulic conductivity and specific storage estimations were based on perfect knowledge of electrical resistivity field. This implies that electrical resistivity will need to be jointly inverted with the hydraulic parameters in future studies and the impact of its uncertainty assessed with respect to the final tomograms of the hydraulic parameters.

Comparative study of methods to estimate hydraulic parameters in the hydraulically undisturbed Opalinus Clay (Switzerland)

Energy Technology Data Exchange (ETDEWEB)

Yu, C.; Matray, J.-M. [Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-aux-Roses, (France); Yu, C.; Gonçalvès, J. [Aix Marseille Université UMR 6635 CEREGE Technopôle Environnement Arbois-Méditerranée Aix-en-Provence, Cedex 4 (France); and others

2017-04-15

The deep borehole (DB) experiment gave the opportunity to acquire hydraulic parameters in a hydraulically undisturbed zone of the Opalinus Clay at the Mont Terri rock laboratory (Switzerland). Three methods were used to estimate hydraulic conductivity and specific storage values of the Opalinus Clay formation and its bounding formations through the 248 m deep borehole BDB-1: application of a Poiseuille-type law involving petrophysical measurements, spectral analysis of pressure time series and in situ hydraulic tests. The hydraulic conductivity range in the Opalinus Clay given by the first method is 2 × 10{sup -14}-6 × 10{sup -13} m s{sup -1} for a cementation factor ranging between 2 and 3. These results show low vertical variability whereas in situ hydraulic tests suggest higher values up to 7 × 10{sup -12} m s{sup -1}. Core analysis provides economical estimates of the homogeneous matrix hydraulic properties but do not account for heterogeneities at larger scale such as potential tectonic conductive features. Specific storage values obtained by spectral analysis are consistent and in the order of 10{sup -6} m{sup -1}, while formulations using phase shift and gain between pore pressure signals were found to be inappropriate to evaluate hydraulic conductivity in the Opalinus Clay. The values obtained are globally in good agreement with the ones obtained previously at the rock laboratory. (authors)

Peatlands as Filters for Polluted Mine Water?—A Case Study from an Uranium-Contaminated Karst System in South Africa—Part II: Examples from Literature and a Conceptual Filter Model

Directory of Open Access Journals (Sweden)

Frank Winde

2011-03-01

Full Text Available As the second part of a series of four, this paper reviews a number of case studies of natural uranium attenuation in peat, as well as underlying chemical mechanisms reported in literature. Based on this review, a generic, conceptual, model for peat to act as filter for dissolved uranium (U is developed for guiding subsequent field investigations. The model consists of a chemical and an hydraulic component which is derived largely from data reported in literature as well as from limited field observations. For the chemical model component 10 different processes, each controlled by factors relating to water chemistry, have been identified to govern the attenuation of U in peat via a net balance of immobilization and remobilization. For the hydraulic aspect of the filter model, five different principal modes of U polluted water coming in contact with peat are discussed, focusing on the associated peat-water contact time as a crucial parameter controlling chemical U attenuation. Moreover, links between the two model components are discussed and, based on the integrated conceptual model, possible effects of natural and anthropogenic events on U attenuation in peatlands are outlined. Guided by the model, various site-specific field and laboratory investigations are finally designed to verify how far the identified generic factors and processes are indeed applicable to the Gerhard Minnebron Peatland.

Analysis of Institutional Press Releases and its Visibility in the Press

Directory of Open Access Journals (Sweden)

José Antonio Alcoceba-Hernando, Ph.D.

2010-01-01

Full Text Available The relationships between institutional communication and media communication influence the shaping of social representations of public issues. This research article analyses these relationships based on the case study of the external communication of a public institution, the press releases of Spain’s Youth Institute (Instituto de la Juventud, aka, Injuve, during three years and their repercussion in the press during the same period of time. The results obtained in this research allowed drawing conclusions on the types of communication production of the aforementioned institution and the news treatment of such pieces of information by the printed and digital media. The press releases and the news items were studied using quantitative media content analysis which focused, especially, in referential issues like the information treatment, the thematic analysis, youth representations in the case of the releases; and the visibility of the press releases in the making of news

3D Hydraulic tomography from joint inversion of the hydraulic heads and self-potential data. (Invited)

Science.gov (United States)

Jardani, A.; Soueid Ahmed, A.; Revil, A.; Dupont, J.

2013-12-01

Pumping tests are usually employed to predict the hydraulic conductivity filed from the inversion of the head measurements. Nevertheless, the inverse problem is strongly underdetermined and a reliable imaging requires a considerable number of wells. We propose to add more information to the inversion of the heads by adding (non-intrusive) streaming potentials (SP) data. The SP corresponds to perturbations in the local electrical field caused directly by the fow of the ground water. These SP are obtained with a set of the non-polarising electrodes installed at the ground surface. We developed a geostatistical method for the estimation of the hydraulic conductivity field from measurements of hydraulic heads and SP during pumping and injection experiments. We use the adjoint state method and a recent petrophysical formulation of the streaming potential problem in which the streaming coupling coefficient is derived from the hydraulic conductivity allowed reducing of the unknown parameters. The geostatistical inverse framework is applied to three synthetic case studies with different number of the wells and electrodes used to measure the hydraulic heads and the streaming potentials. To evaluate the benefits of the incorporating of the streaming potential to the hydraulic data, we compared the cases in which the data are coupled or not to map the hydraulic conductivity. The results of the inversion revealed that a dense distribution of electrodes can be used to infer the heterogeneities in the hydraulic conductivity field. Incorporating the streaming potential information to the hydraulic head data improves the estimate of hydraulic conductivity field especially when the number of piezometers is limited.

Hydraulic Shearing and Hydraulic Jacking Observed during Hydraulic Stimulations in Fractured Geothermal Reservoir in Pohang, Korea

Science.gov (United States)

Min, K. B.; Park, S.; Xie, L.; Kim, K. I.; Yoo, H.; Kim, K. Y.; Choi, J.; Yoon, K. S.; Yoon, W. S.; Lee, T. J.; Song, Y.

2017-12-01

Enhanced Geothermal System (EGS) relies on sufficient and irreversible enhancement of reservoir permeability through hydraulic stimulation and possibility of such desirable change of permeability is an open question that can undermine the universality of EGS concept. We report results of first hydraulic stimulation campaign conducted in two deep boreholes in fractured granodiorite geothermal reservoir in Pohang, Korea. Borehole PX-1, located at 4.22 km, was subjected to the injection of 3,907 m3 with flow rate of up to 18 kg/s followed by bleeding off of 1,207 m3. The borehole PX-2, located at 4.35 km, was subjected to the injection of 1,970 m3 with flow rate of up to 46 kg/sIn PX-1, a sharp distinct decline of wellhead pressure was observed at around 16 MPa of wellhead pressure which was similar to the predicted injection pressure to induce hydraulic shearing. Injectivity interpretation before and after the hydraulic shearing indicates that permanent increase of permeability was achieved by a factor of a few. In PX-2, however, injectivity was very small and hydraulic shearing was not observed due possibly to the near wellbore damage made by the remedying process of lost circulation such as using lost circulation material during drilling. Flow rate of larger than 40 kg/s was achieved at very high well head pressure of nearly 90 MPa. Hydraulic jacking, that is reversible opening and closure of fracture with change of injection pressure, was clearly observed. Although sharp increase of permeability due to fracture opening was achieved with elevated injection pressure, the increased permeability was reversed with decreased injection pressure.Two contrasting response observed in the same reservoir at two different boreholes which is apart only 600 m apart provide important implication that can be used for the stimulation strategy for EGS.This work was supported by the New and Renewable Energy Technology Development Program of the Korea Institute of Energy Technology

Hydraulic Stability of Accropode Armour

DEFF Research Database (Denmark)

Jensen, T.; Burcharth, H. F.; Frigaard, Peter

The present report describes the hydraulic model tests of Accropode armour layers carried out at the Hydraulics Laboratory at Aalborg University from November 1995 through March 1996. The objective of the model tests was to investigate the hydraulic stability of Accropode armour layers...... with permeable core (crushed granite with a gradation of 5-8 mm). The outcome of this study is described in "Hydraulic Stability of Single-Layer Dolos and Accropode Armour Layers" by Christensen & Burcharth (1995). In January/February 1996, Research Assistant Thomas Jensen carried out a similar study...

WordPress Top Plugins

CERN Document Server

Corbin, Brandon

2010-01-01

Time flies when you're having fun. This is the right way to describe this WordPress Top Plugins book by Brandon Corbin. With real world examples and by showing you the perks of having these plugins installed on your websites, the author is all set to captivate your interest from start to end. Regardless of whether this is your first time working with WordPress, or you're a seasoned WordPress coding ninja, WordPress Top Plugins will walk you through finding and installing the best plugins for generating and sharing content, building communities and reader base, and generating real advertising r

Digital switched hydraulics

Science.gov (United States)

Pan, Min; Plummer, Andrew

2018-06-01

This paper reviews recent developments in digital switched hydraulics particularly the switched inertance hydraulic systems (SIHSs). The performance of SIHSs is presented in brief with a discussion of several possible configurations and control strategies. The soft switching technology and high-speed switching valve design techniques are discussed. Challenges and recommendations are given based on the current research achievements.

A New Method for the Deposition of Metallic Silver on Porous Ceramic Water Filters

Directory of Open Access Journals (Sweden)

Kathryn N. Jackson

2018-01-01

Full Text Available A new method of silver application to a porous ceramic water filter used for point-of-use water treatment is developed. We evaluated filter performance for filters manufactured by the conventional method of painting an aqueous suspension of silver nanoparticles onto the filter and filters manufactured with a new method that applies silver nitrate to the clay-water-sawdust mixture prior to pressing and firing the filter. Filters were evaluated using miscible displacement flow-through experiments with pulse and continuous-feed injections of E. coli. Flow characteristics were quantified by tracer experiments using [3H]H2O. Experiments using pulse injections of E. coli showed similar performance in breakthrough curves between the two application methods. Long-term challenge tests performed with a continuous feed of E. coli and growth medium resulted in similar log removal rates, but the removal rate by nanosilver filters decreased over time. Silver nitrate filters provided consistent removal with lower silver levels in the effluent and effective bacterial disinfection. Results from continued use with synthetic groundwater over 4 weeks, with a pulse injection of E. coli at 2 and 4 weeks, support similar conclusions—nanosilver filters perform better initially, but after 4 weeks of use, nanosilver filters suffer larger decreases in performance. Results show that including silver nitrate in the mixing step may effectively reduce costs, improve silver retention in the filter, increase effective lifespan, and maintain effective pathogen removal while also eliminating the risk of exposure to inhalation of silver nanoparticles by workers in developing-world filter production facilities.

Hydraulic hoisting and backfilling

Science.gov (United States)

Sauermann, H. B.

In a country such as South Africa, with its large deep level mining industry, improvements in mining and hoisting techniques could result in substantial savings. Hoisting techniques, for example, may be improved by the introduction of hydraulic hoisting. The following are some of the advantages of hydraulic hoisting as against conventional skip hoisting: (1) smaller shafts are required because the pipes to hoist the same quantity of ore hydraulically require less space in the shaft than does skip hoisting equipment; (2) the hoisting capacity of a mine can easily be increased without the necessity of sinking new shafts. Large savings in capital costs can thus be made; (3) fully automatic control is possible with hydraulic hoisting and therefore less manpower is required; and (4) health and safety conditions will be improved.

Metal removal efficiency, operational life and secondary environmental impacts of a stormwater filter developed from iron-oxide-amended bottom ash.

Science.gov (United States)

Ilyas, Aamir; Muthanna, Tone M

2017-12-06

The aim of this paper was to conduct pilot-scale column tests on an alternative treatment filter designed for the treatment of highway stormwater in cold climates. The study evaluated adsorption performance of the filter with regard to the four most commonly found metals (Cu, Ni, Pb, and Zn) in highway stormwater. An alternative method was used to estimate the operational life of the filter from the adsorption test data without a breakthrough under high hydraulic loads. The potential environmental impact of the filter was assessed by comparing desorption test data with four different environmental quality standards. The proposed filter achieved high adsorption (over 90%) of the target metals. The comparisons of desorption and leaching data with the environmental standards indicated that iron-oxide/bottom ash was non-hazardous, reusable and without serious environmental risks. The operational life and filter dimensions were highly dependent on rainfall depth, which indicated that the filter design would have to be adapted to suit the climate. To fully appreciate the performance and environmental aspects, the filter unit should be tested in the field and the testing should explicitly include ecotoxicological and life cycle impacts.

Which Freedom of the Press?

DEFF Research Database (Denmark)

Rytter, Jens Elo

2010-01-01

The article surveys the historical and current meaning of "Freedom of the Press" in constitutional and human rights law. Two different conceptions exist, the narrow one defining freedom of the press as the freedom of every one to publish without prior restraint, the broader one defining it as a...... privileged freedom of the organised press to gather and report on information of public interest. These two conceptions have very different answers to the question of whether the press should enjoy some privilege to be exempt from ordinary legislation when such legislation restricts the access of the press to inform...

Preliminary study on filamentous particle distribution in septic tank effluent and their impact on filter cake development.

Science.gov (United States)

Spychała, Marcin; Nieć, Jakub; Pawlak, Maciej

2013-01-01

In this paper, the preliminary study on the impact of filamentous particles (FP) in the septic tank effluent (STE) on filter cake (FC) development was presented. The number, length and diameter (30 p./cm3, 451 and 121 microm, respectively, on average) of FPs were measured using microscope image analysis of STE samples condensed using a vacuum evaporation set. Results of this study showed, that 0.73% of volatile suspended solids (VSSs) mass from the STE occurs in the form of FPs. No correlation between FP total mass and VSS was found. An experiment with a layer of FPs simulated by ground toilet paper was conducted and showed the impact of this layer (4.89 mg/cm2) on wastewater hydraulic conductivity--for an FC with FPs (FC-FP), hydraulic conductivity was seven times lower than for the FC without the FP layer, and on outflow quality (lower concentration of organic matter expressed as chemical oxygen demand (COD) in effluent from the FC-FP filter than in the effluent from the FC filter: 618 and 732 gO2/m3, respectively). Despite a relatively small amount of FPs in STE solids (as volume fraction), they play an important role in FC development due to their relatively high length and low degradability. Probably relatively small pores of the FC containing FPs (FC-FP) caused a small particle blocking and a decrease in permeability.

Hot-pressing steatite bodies

International Nuclear Information System (INIS)

Aparicio Arroyo, E.

1967-01-01

Requirements for some special nuclear engineering ceramic shapes are: big size, impervious, dimensional accuracy and good mechanical and dielectric properties. Limitations of te conventional methods and advantages of te hot pressing techniques for the manufacturing of these shapes are discussed. Hot pressing characteristics of a certain steatite powder are studied. Occurrence of an optimum densification temperature just above the tale decomposition range is found. Experimental data show that the height/diameter ratio of the specimen has no effect on the sintering conditions. Increasing darkness from the graphite mould is detected above the optimum temperature. The hot-pressed steatite is compared with a fired dry-pressed sample of the same composition. (Author) 13 refs

CRITICALITY CURVES FOR PLUTONIUM HYDRAULIC FLUID MIXTURES

International Nuclear Information System (INIS)

WITTEKIND WD

2007-01-01

This Calculation Note performs and documents MCNP criticality calculations for plutonium (100% 239 Pu) hydraulic fluid mixtures. Spherical geometry was used for these generalized criticality safety calculations and three geometries of neutron reflection are: (sm b ullet)bare, (sm b ullet)1 inch of hydraulic fluid, or (sm b ullet)12 inches of hydraulic fluid. This document shows the critical volume and critical mass for various concentrations of plutonium in hydraulic fluid. Between 1 and 2 gallons of hydraulic fluid were discovered in the bottom of HA-23S. This HA-23S hydraulic fluid was reported by engineering to be Fyrquel 220. The hydraulic fluid in GLovebox HA-23S is Fyrquel 220 which contains phosphorus. Critical spherical geometry in air is calculated with 0 in., 1 in., or 12 inches hydraulic fluid reflection

Derivation of site-specific relationships between hydraulic parameters and p-wave velocities based on hydraulic and seismic tomography

Energy Technology Data Exchange (ETDEWEB)

Brauchler, R.; Doetsch, J.; Dietrich, P.; Sauter, M.

2012-01-10

In this study, hydraulic and seismic tomographic measurements were used to derive a site-specific relationship between the geophysical parameter p-wave velocity and the hydraulic parameters, diffusivity and specific storage. Our field study includes diffusivity tomograms derived from hydraulic travel time tomography, specific storage tomograms, derived from hydraulic attenuation tomography, and p-wave velocity tomograms, derived from seismic tomography. The tomographic inversion was performed in all three cases with the SIRT (Simultaneous Iterative Reconstruction Technique) algorithm, using a ray tracing technique with curved trajectories. The experimental set-up was designed such that the p-wave velocity tomogram overlaps the hydraulic tomograms by half. The experiments were performed at a wellcharacterized sand and gravel aquifer, located in the Leine River valley near Göttingen, Germany. Access to the shallow subsurface was provided by direct-push technology. The high spatial resolution of hydraulic and seismic tomography was exploited to derive representative site-specific relationships between the hydraulic and geophysical parameters, based on the area where geophysical and hydraulic tests were performed. The transformation of the p-wave velocities into hydraulic properties was undertaken using a k-means cluster analysis. Results demonstrate that the combination of hydraulic and geophysical tomographic data is a promising approach to improve hydrogeophysical site characterization.

Attentional Focus and Grip Width Influences on Bench Press Resistance Training.

Science.gov (United States)

Calatayud, Joaquin; Vinstrup, Jonas; Jakobsen, Markus D; Sundstrup, Emil; Colado, JuanCarlos; Andersen, Lars L

2018-04-01

This study evaluated the influence of different attentional foci for varied grip widths in the bench press. Eighteen resistance-trained men were familiarized with the procedure and performed a one-repetition maximum (1RM) test during Session 1. In Session 2, they used three different standardized grip widths (100%, 150%, and 200% of biacromial width distance) in random order at 50% of 1RM while also engaged in three different attention focus conditions (external focus on the bench press, internal focus on pectoralis major muscles, and internal focus on triceps brachii muscles). Surface electromyography (EMG) signals were recorded from the triceps brachii and pectoralis major, and peak EMG of the filtered signals were normalized to maximum EMG of each muscle. Both grip width and focus influenced the muscle activity level, but there were no significant interactions between these variables. Exploratory analyses suggested that an internal focus may slightly (4%-6%) increase pectoralis major activity at wider grip widths and triceps brachii activity at narrower grip widths, but this should be confirmed or rejected in a study with a larger sample size or through a meta-analysis of research to date.

Mathematical modelling of wet paper pressing

NARCIS (Netherlands)

Bežanovic, D.

2005-01-01

The aim of this project is to reduce energy costs in paper production by optimising the process in the press section of a paper machine. In this press section water is squeezed as it passes through the press nip. In a modern press section the moisture content of the sheet after three or four presses

Hydraulic Hybrid Vehicle Publications | Transportation Research | NREL

Science.gov (United States)

Hydraulic Hybrid Vehicle Publications Hydraulic Hybrid Vehicle Publications The following technical papers and fact sheets provide information about NREL's hydraulic hybrid fleet vehicle evaluations . Refuse Trucks Project Startup: Evaluating the Performance of Hydraulic Hybrid Refuse Vehicles. Bob

Biodegradation of methyl tertiary butyl ether (MTBE) using a granular activated carbon trickling filter

Energy Technology Data Exchange (ETDEWEB)

Converse, B.M.; Schroeder, E.D.; Chang, D.P.Y.

1999-07-01

A pilot scale trickling filter was constructed using granular activated carbon (GAC) as the packing medium and inoculated with a microbial culture known to degrade MTBE. The packing dimensions were 0.076 m in diameter and 0.22 m deep. The unit operated with recycling flow for two months before a biofilm was observed on the GAC. After two additional months the biofilm had visibly spread throughout the packing. A few pieces of GAC were placed in a sealed bottle with MTBE-contaminated water and nutrients. Headspace analysis performed over 14 days confirmed that MTBE degradation was occurring. The trickling filter was converted to continuous flow and operated for one month at a nominal flow rate of 0.1 L/min and a hydraulic loading rate of 32 m{sup 3}/m{sup 2}-d. Samples were collected for analysis at the spray nozzle and at the bottom of the trickling filter. Fractional removal varied with influent MTBE concentration, temperature and liquid flow rate. Percent MTBE removal was as high as 85%. A mechanical failure resulted in the trickling filter bed drying and percent removal dropping to less than 1 percent. However, the system recovered within five days.

MEDOF - MINIMUM EUCLIDEAN DISTANCE OPTIMAL FILTER

Science.gov (United States)

Barton, R. S.

1994-01-01

values of amplitude and phase for the k whose metric was largest, as well as consistency checks, are reported. A finer search can be done in the neighborhood of the optimal k if desired. The filter finally selected is written to disk in terms of drive values, not in terms of the filter's complex transmittance. Optionally, the impulse response of the filter may be created to permit users to examine the response for the features the algorithm deems important to the recognition process under the selected metric, limitations of the filter SLM, etc. MEDOF uses the filter SLM to its greatest potential, therefore filter competence is not compromised for simplicity of computation. MEDOF is written in C-language for Sun series computers running SunOS. With slight modifications, it has been implemented on DEC VAX series computers using the DEC-C v3.30 compiler, although the documentation does not currently support this platform. MEDOF can also be compiled using Borland International Inc.'s Turbo C++ v1.0, but IBM PC memory restrictions greatly reduce the maximum size of the reference images from which the filters can be calculated. MEDOF requires a two dimensional Fast Fourier Transform (2DFFT). One 2DFFT routine which has been used successfully with MEDOF is a routine found in "Numerical Recipes in C: The Art of Scientific Programming," which is available from Cambridge University Press, New Rochelle, NY 10801. The standard distribution medium for MEDOF is a .25 inch streaming magnetic tape cartridge (Sun QIC-24) in UNIX tar format. MEDOF was developed in 1992-1993.

Hydraulic Yaw System for Wind Turbines with New Compact Hydraulic Motor Principle

DEFF Research Database (Denmark)

Sørensen, Rasmus Mørk; Hansen, Michael Rygaard; Mouritsen, Ole Ø.

2011-01-01

This paper presents a new hydraulic yaw system for wind turbines. The basic component is a new type of hydraulic motor characterized by an extraordinary high specific displacement yielding high output torque in a compact form. The focus in the paper is the volumetric efficiency of the motor, which...

Gravimetric Measurements of Filtering Facepiece Respirators Challenged With Diesel Exhaust.

Science.gov (United States)

Satish, Swathi; Swanson, Jacob J; Xiao, Kai; Viner, Andrew S; Kittelson, David B; Pui, David Y H

2017-07-01

Elevated concentrations of diesel exhaust have been linked to adverse health effects. Filtering facepiece respirators (FFRs) are widely used as a form of respiratory protection against diesel particulate matter (DPM) in occupational settings. Previous results (Penconek A, Drążyk P, Moskal A. (2013) Penetration of diesel exhaust particles through commercially available dust half masks. Ann Occup Hyg; 57: 360-73.) have suggested that common FFRs are less efficient than would be expected for this purpose based on their certification approvals. The objective of this study was to measure the penetration of DPM through NIOSH-certified R95 and P95 electret respirators to verify this result. Gravimetric-based penetration measurements conducted using polytetrafluoroethylene (PTFE) and polypropylene (PP) filters were compared with penetration measurements made with a Scanning Mobility Particle Sizer (SMPS, TSI Inc.), which measures the particle size distribution. Gravimetric measurements using PP filters were variable compared to SMPS measurements and biased high due to adsorption of gas phase organic material. Relatively inert PTFE filters adsorbed less gas phase organic material resulting in measurements that were more accurate. To attempt to correct for artifacts associated with adsorption of gas phase organic material, primary and secondary filters were used in series upstream and downstream of the FFR. Correcting for adsorption by subtracting the secondary mass from the primary mass improved the result for both PTFE and PP filters but this correction is subject to 'equilibrium' conditions that depend on sampling time and the concentration of particles and gas phase hydrocarbons. Overall, the results demonstrate that the use of filters to determine filtration efficiency of FFRs challenged with diesel exhaust produces erroneous results due to the presence of gas phase hydrocarbons in diesel exhaust and the tendency of filters to adsorb organic material. Published by

Contribuição da estrutura interna na perda de carga de filtros de areia utilizados na irrigação Contribution of the internal structure in the sand filters head loss used in irrigation

Directory of Open Access Journals (Sweden)

Marcio Mesquita

2012-02-01

Full Text Available A dinâmica de operação dos filtros de areia afeta o desempenho hidráulico do sistema de irrigação, elevando a perda de carga e alterando a altura manométrica total do sistema. Buscando entender parte dessa dinâmica, o objetivo deste trabalho foi determinar o efeito da estrutura interna de filtros de areia na perda de carga de três modelos de equipamentos fabricados no Brasil, sem a presença do elemento filtrante e utilizando água limpa. Adicionalmente, com o ajuste do modelo matemático exponencial aos dados experimentais, procurou-se estabelecer comparações entre os tipos de estrutura dos filtros avaliados. Os ensaios foram realizados em um módulo experimental construído no Laboratório de Hidráulica e Irrigação da FEAGRI/UNICAMP. Os resultados mostraram que a estrutura hidráulica interna dos filtros determinou comportamentos hidráulicos diferenciados e que os tipos de estruturas (placa difusora e drenos alteraram o padrão de operação dos modelos ensaiados. A função matemática proposta representou, significativamente, o fenômeno físico de perda de carga para as condições do experimento.The dynamic of operation of sand filters affect the hydraulic performance of irrigation systems, increasing the head loss and changing the total dynamic head of the system. Trying to understand part of this dynamic, the objective of this research was to determine the effect of internal hydraulic structures in the head loss of three sand filters of commercial models, manufactured in Brazil and operating without the filter layer and with clean water. In addition, using an exponential mathematical model adjusted to the experimental data, comparisons among types of structure of each evaluated filter were performed. The trails were accomplished in the experimental module developed in the Laboratory of Hydraulics and Irrigation of FEAGRI / UNICAMP. The results showed that the filters structures determined differentiate hydraulic behaviors

Hydraulic turbines and auxiliary equipment

Energy Technology Data Exchange (ETDEWEB)

Luo Gaorong [Organization of the United Nations, Beijing (China). International Centre of Small Hydroelectric Power Plants

1995-07-01

This document presents a general overview on hydraulic turbines and auxiliary equipment, emphasizing the turbine classification, in accordance with the different types of turbines, standard turbine series in China, turbine selection based on the basic data required for the preliminary design, general hill model curves, chart of turbine series and the arrangement of application for hydraulic turbines, hydraulic turbine testing, and speed regulating device.

Subsea Hydraulic Leakage Detection and Diagnosis

OpenAIRE

Stavenes, Thomas

2010-01-01

The motivation for this thesis is reduction of hydraulic emissions, minimizing of process emergency shutdowns, exploitation of intervention capacity, and reduction of costs. Today, monitoring of hydraulic leakages is scarce and the main way to detect leakage is the constant need for filling of hydraulic fluid to the Hydraulic Power Unit (HPU). Leakage detection and diagnosis has potential, which would be adressed in this thesis. A strategy towards leakage detection and diagnosis is given....

Functional water flow pathways and hydraulic regulation in the xylem network of Arabidopsis.

Science.gov (United States)

Park, Joonghyuk; Kim, Hae Koo; Ryu, Jeongeun; Ahn, Sungsook; Lee, Sang Joon; Hwang, Ildoo

2015-03-01

In vascular plants, the xylem network constitutes a complex microfluidic system. The relationship between vascular network architecture and functional hydraulic regulation during actual water flow remains unexplored. Here, we developed a method to visualize individual xylem vessels of the 3D xylem network of Arabidopsis thaliana, and to analyze the functional activities of these vessels using synchrotron X-ray computed tomography with hydrophilic gold nanoparticles as flow tracers. We show how the organization of the xylem network changes dynamically throughout the plant, and reveal how the elementary units of this transport system are organized to ensure both long-distance axial water transport and local lateral water transport. Xylem vessels form distinct clusters that operate as functional units, and the activity of these units, which determines water flow pathways, is modulated not only by varying the number and size of xylem vessels, but also by altering their interconnectivity and spatial arrangement. Based on these findings, we propose a regulatory model of water transport that ensures hydraulic efficiency and safety. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Development of Aerosol Scrubbing Test Loop for Containment Filtered Venting System

International Nuclear Information System (INIS)

Lee, Doo Yong; Jung, Woo Young; Lee, Hyun Chul; Lee, Jong Chan; Kim, Gyu Tae

2016-01-01

The scrubber tank is filled with scrubbing water with the chemical additives. The droplet separator based on a cyclone is installed above the scrubbing water pool to remove the large droplets that may clog a metal fiber filter installed at the upper section of the scrubber tank. The outlet piping is connected from the scrubber tank to the molecular sieve to chemically remove the gaseous iodine. The aerosol as a particle is physically captured in the scrubbing water pool passing through the scrubbing nozzle as well as the metal fiber filter. The gaseous iodine such as molecular iodine as well as organic iodide is chemically removed in the scrubbing water pool and molecular sieve. The thermal-hydraulic as well as scrubbing performance for the CFVS should be verified with the experiments. The experiment can be divided into the filtration component based experiment and whole system based one. In this paper, the aerosol scrubbing test loop developed to test the thermal-hydraulic and aerosol scrubbing performance of the scrubbing nozzle with the scrubbing water pool is introduced. The aerosol scrubbing test loop has been developed as a part of the Korean CFVS project. In this loop, the filtration components such as the scrubbing nozzle submerged in the scrubbing water pool as well as the cyclone as droplet separator can be tested under the CFVS operating conditions. The aerosol scrubbing performance of the filtration components including pool scrubbing behavior can be tested with the aerosol generation and feeding system and aerosol measurement system.

Development of Aerosol Scrubbing Test Loop for Containment Filtered Venting System

Energy Technology Data Exchange (ETDEWEB)

Lee, Doo Yong; Jung, Woo Young; Lee, Hyun Chul; Lee, Jong Chan; Kim, Gyu Tae [FNC Technology, Yongin (Korea, Republic of)

2016-05-15

The scrubber tank is filled with scrubbing water with the chemical additives. The droplet separator based on a cyclone is installed above the scrubbing water pool to remove the large droplets that may clog a metal fiber filter installed at the upper section of the scrubber tank. The outlet piping is connected from the scrubber tank to the molecular sieve to chemically remove the gaseous iodine. The aerosol as a particle is physically captured in the scrubbing water pool passing through the scrubbing nozzle as well as the metal fiber filter. The gaseous iodine such as molecular iodine as well as organic iodide is chemically removed in the scrubbing water pool and molecular sieve. The thermal-hydraulic as well as scrubbing performance for the CFVS should be verified with the experiments. The experiment can be divided into the filtration component based experiment and whole system based one. In this paper, the aerosol scrubbing test loop developed to test the thermal-hydraulic and aerosol scrubbing performance of the scrubbing nozzle with the scrubbing water pool is introduced. The aerosol scrubbing test loop has been developed as a part of the Korean CFVS project. In this loop, the filtration components such as the scrubbing nozzle submerged in the scrubbing water pool as well as the cyclone as droplet separator can be tested under the CFVS operating conditions. The aerosol scrubbing performance of the filtration components including pool scrubbing behavior can be tested with the aerosol generation and feeding system and aerosol measurement system.

Hydraulic fracturing of rock-fill dam

Directory of Open Access Journals (Sweden)

Jun-Jie WANG

2016-02-01

Full Text Available The condition in which hydraulic fracturing in core of earth-rock fill dam maybe induced, the mechanism by which the reason of hydraulic fracturing canbe explained, and the failure criterion by which the occurrence of hydraulicfracturing can be determined, were investigated. The condition dependson material properties such as, cracks in the core and low permeability ofcore soil, and “water wedging” action in cracks. An unsaturated core soiland fast impounding are the prerequisites for the formation of “waterwedging” action. The mechanism of hydraulic fracturing can be explainedby fracture mechanics. The crack propagation induced by water pressuremay follow any of mode I, mode II and mixed mode I-II. Based on testingresults of a core soil, a new criterion for hydraulic fracturing was suggested,from which mechanisms of hydraulic fracturing in the core of rock-fill damwere discussed. The results indicated that factors such as angle betweencrack surface and direction of principal stress, local stress state at thecrack, and fracture toughness KIC of core soil may largely affect theinduction of hydraulic fracturing and the mode of the propagation of thecrack.The condition in which hydraulic fracturing in core of earth-rock fill dam maybe induced, the mechanism by which the reason of hydraulic fracturing canbe explained, and the failure criterion by which the occurrence of hydraulicfracturing can be determined, were investigated. The condition dependson material properties such as, cracks in the core and low permeability ofcore soil, and “water wedging” action in cracks. An unsaturated core soiland fast impounding are the prerequisites for the formation of “waterwedging” action. The mechanism of hydraulic fracturing can be explainedby fracture mechanics. The crack propagation induced by water pressuremay follow any of mode I, mode II and mixed mode I-II. Based on testingresults of a core soil, a new criterion for hydraulic fracturing

Combined hydraulic and regenerative braking system

Science.gov (United States)

Venkataperumal, R.R.; Mericle, G.E.

1979-08-09

A combined hydraulic and regenerative braking system and method for an electric vehicle is disclosed. The braking system is responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

Four Theories of the Press.

Science.gov (United States)

Siebert, Fred S.; And Others

A systematic understanding of the press requires an understanding of the social and political structures within which the press operates. This book discusses four theories that have determined the kind of press the Western world has had: authoritarian, libertarian, socially responsible, and Soviet communist. Each chapter discusses press…

WordPress 3.7 complete

CERN Document Server

Król, Karol

2013-01-01

WordPress 3.5 Complete: Third Edition is a comprehensive and step-by-step tutorial packed with screenshots and examples to make it easy and quick to pick it up.This WordPress book is a guide to WordPress for online publishers and web developers. If you are new to blogging and want to create your own blog or website from scratch, then ""WordPress 3.5 Complete: Third Edition"" is for you. No prior knowledge of HTML/CSS or PHP is required.

Effects of prescribed burning on ecophysiological, anatomical and stem hydraulic properties in Pinus pinea L.

Science.gov (United States)

Battipaglia, Giovanna; Savi, Tadeja; Ascoli, Davide; Castagneri, Daniele; Esposito, Assunta; Mayr, Stefan; Nardini, Andrea

2016-08-01

Prescribed burning (PB) is a widespread management technique for wildfire hazard abatement. Understanding PB effects on tree ecophysiology is key to defining burn prescriptions aimed at reducing fire hazard in Mediterranean pine plantations, such as Pinus pinea L. stands. We assessed physiological responses of adult P. pinea trees to PB using a combination of dendroecological, anatomical, hydraulic and isotopic analyses. Tree-ring widths, xylem cell wall thickness, lumen area, hydraulic diameter and tree-ring δ(13)C and δ(18)O were measured in trees on burned and control sites. Vulnerability curves were elaborated to assess tree hydraulic efficiency or safety. Despite the relatively intense thermal treatment (the residence time of temperatures above 50 °C at the stem surface ranged between 242 and 2239 s), burned trees did not suffer mechanical damage to stems, nor significant reduction in radial growth. Moreover, the PB did not affect xylem structure and tree hydraulics. No variations in (13)C-derived water use efficiency were recorded. This confirmed the high resistance of P. pinea to surface fire at the stem base. However, burned trees showed consistently lower δ(18)O values in the PB year, as a likely consequence of reduced competition for water and nutrients due to the understory burning, which increased both photosynthetic activity and stomatal conductance. Our multi-approach analysis offers new perspectives on post-fire survival strategies of P. pinea in an environment where fires are predicted to increase in frequency and severity during the 21st century. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A Computational Model of Hydraulic Volume Displacement Drive

Directory of Open Access Journals (Sweden)

V. N. Pil'gunov

2014-01-01

Full Text Available The paper offers a computational model of industrial-purpose hydraulic drive with two hydraulic volume adjustable working chamber machines (pump and motor. Adjustable pump equipped with the pressure control unit can be run together with several adjustable hydraulic motors on the principle of three-phase hydraulic socket-outlet with high-pressure lines, drain, and drainage system. The paper considers the pressure-controlled hydrostatic transmission with hydraulic motor as an output link. It shows a possibility to create a saving hydraulic drive using a functional tie between the adjusting parameters of the pump and hydraulic motor through the pressure difference, torque, and angular rate of the hydraulic motor shaft rotation. The programmable logic controller can implement such tie. The Coulomb and viscous frictions are taken into consideration when developing a computational model of the hydraulic volume displacement drive. Discharge balance considers external and internal leakages in equivalent clearances of hydraulic machines, as well as compression loss volume caused by hydraulic fluid compressibility and deformation of pipe walls. To correct dynamic properties of hydraulic drive, the paper offers that in discharge balance are included the additional regulated external leakages in the open circuit of hydraulic drive and regulated internal leakages in the closed-loop circuit. Generalized differential equations having functional multipliers and multilinked nature have been obtained to describe the operation of hydraulic positioning and speed drive with two hydraulic volume adjustable working chamber machines. It is shown that a proposed computational model of hydraulic drive can be taken into consideration in development of LS («Load-Sensing» drives, in which the pumping pressure is tuned to the value required for the most loaded slave motor to overcome the load. Results attained can be used both in designing the industrial-purpose heavy

Solidification of ion-exchange resins by hydrothermal hot-pressing

International Nuclear Information System (INIS)

Kaneko, M.

1993-01-01

The solidification reaction which easily occurs while continuously keeping the mixture of cation and anion exchange resins compressed under hydrothermal conditions has been demonstrated. Dehydration was considered to occur between sulphonic acid (-SO 3 H) from the cation exchange resin and quaternary ammonium [-CH 2 -N(CH 3 ) 3 OH] from anion-exchange resin-on terminal groups. The cation-and anion-exchange resins were mixed in a 1:1 weight ratio, put in a hot-pressing autoclave and compressed between pistons from the top and bottom at 600 kg cm -2 pressure. The material was continuously compressed during hydrothermal treatment at 200 kg cm -2 by a hydraulic jack and heated to a desired temperature with an induction heater. This system could be used for rapid temperature increasing up to 30 o c min -1 . The pressure and temperature were kept constant for 10 min. The autoclave was cooled to room temperature after the hydrothermal treatment. After the specimen was taken out, the ion-exchange radical reactions were estimated and the product structures were examined. The cation- and anion-exchange resin mixture was solidified. The resultant solidified body at a 300 o C reaction condition for 10 min had a 1.0 g cm -3 density and 700 kg cm -2 compressive strength, and the weight loss did not change in distilled water for 2 weeks. On the other hand, a solidification reaction did not occur at below 250 o C when only the cation or anion was solidified, but they were decomposed. These results suggest that a mixture of cation- and anion-exchange resins causes a solidification reaction under hydrothermal hot-pressing conditions at 300 o C. (author)

Hydraulic lifter for an underwater drilling rig

Energy Technology Data Exchange (ETDEWEB)

Garan' ko, Yu L

1981-01-15

A hydraulic lifter is suggested for an underwater drilling rig. It includes a base, hydraulic cylinders for lifting the drilling pipes connected to the clamp holder and hydraulic distributor. In order to simplify the design of the device, the base is made with a hollow chamber connected to the rod cavities and through the hydraulic distributor to the cavities of the hydraulic cylinders for lifting the drilling pipes. The hydraulic distributor is connected to the hydrosphere through the supply valve with control in time or by remote control. The base is equipped with reverse valves whose outlets are on the support surface of the base.

Research on the Random Shock Vibration Test Based on the Filter-X LMS Adaptive Inverse Control Algorithm

Directory of Open Access Journals (Sweden)

Wang Wei

2016-01-01

Full Text Available The related theory and algorithm of adaptive inverse control were presented through the research which pointed out the adaptive inverse control strategy could effectively eliminate the noise influence on the system control. Proposed using a frequency domain filter-X LMS adaptive inverse control algorithm, and the control algorithm was applied to the two-exciter hydraulic vibration test system of random shock vibration control process and summarized the process of the adaptive inverse control strategies in the realization of the random shock vibration test. The self-closed-loop and field test show that using the frequency-domain filter-X LMS adaptive inverse control algorithm can realize high precision control of random shock vibration test.

Smashing WordPress Beyond the Blog

CERN Document Server

Hedengren, Thord Daniel

2011-01-01

Smashing WordPress shows you how to utilize the power of the WordPress platform, and provides a creative spark to help you build WordPress-powered sites that go beyond the obvious. The second edition of Smashing WordPress has been updated for WordPress 3.1+, which includes internal, custom post types, the admin bar, and lots of other useful new features. You will learn the core concepts used to post types, the admin bar, and lots of other useful new features. You will learn the core concepts used to build just about anything in WordPress, resulting in fast deployments and greater design flexib

Smashing WordPress Beyond the Blog

CERN Document Server

Hedengren, Thord Daniel

2012-01-01

The ultimate guide to WordPress, from the world's most popular resource for web designers and developers As one of the hottest tools on the web today for creating a blog, WordPress has evolved to be much more that just a blogging platform and has been pushed beyond its original purpose. With this new edition of a perennially popular WordPress resource, Smashing Magazine offers you the information you need so you can maximize the potential and power of WordPress. WordPress expert Thord Daniel Hedengren takes you beyond the basic blog to show you how to leverage the capabilities of WordPress to

46 CFR 112.50-3 - Hydraulic starting.

Science.gov (United States)

2010-10-01

... POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-3 Hydraulic starting. A hydraulic starting system must meet the following: (a) The hydraulic starting system must be a... 46 Shipping 4 2010-10-01 2010-10-01 false Hydraulic starting. 112.50-3 Section 112.50-3 Shipping...

Hydraulic testing in crystalline rock

International Nuclear Information System (INIS)

Almen, K.E.; Andersson, J.E.; Carlsson, L.; Hansson, K.; Larsson, N.A.

1986-12-01

Swedish Geolocical Company (SGAB) conducted and carried out single-hole hydraulic testing in borehole Fi 6 in the Finnsjoen area of central Sweden. The purpose was to make a comprehensive evaluation of different methods applicable in crystalline rocks and to recommend methods for use in current and scheduled investigations in a range of low hydraulic conductivity rocks. A total of eight different methods of testing were compared using the same equipment. This equipment was thoroughly tested as regards the elasticity of the packers and change in volume of the test section. The use of a hydraulically operated down-hole valve enabled all the tests to be conducted. Twelve different 3-m long sections were tested. The hydraulic conductivity calculated ranged from about 5x10 -14 m/s to 1x10 -6 m/s. The methods used were water injection under constant head and then at a constant rate-of-flow, each of which was followed by a pressure fall-off period. Water loss, pressure pulse, slug and drill stem tests were also performed. Interpretation was carried out using standard transient evaluation methods for flow in porous media. The methods used showed themselves to be best suited to specific conductivity ranges. Among the less time-consuming methods, water loss, slug and drill stem tests usually gave somewhat higher hydraulic conductivity values but still comparable to those obtained using the more time-consuming tests. These latter tests, however, provided supplementary information on hydraulic and physical properties and flow conditions, together with hydraulic conductivity values representing a larger volume of rock. (orig./HP)

Numerical and experimental approaches to study soil transport and clogging in granular filters

Science.gov (United States)

Kanarska, Y.; Smith, J. J.; Ezzedine, S. M.; Lomov, I.; Glascoe, L. G.

2012-12-01

Failure of a dam by erosion ranks among the most serious accidents in civil engineering. The best way to prevent internal erosion is using adequate granular filters in the transition areas where important hydraulic gradients can appear. In case of cracking and erosion, if the filter is capable of retaining the eroded particles, the crack will seal and the dam safety will be ensured. Numerical modeling has proved to be a cost-effective tool for improving our understanding of physical processes. Traditionally, the consideration of flow and particle transport in porous media has focused on treating the media as continuum. Practical models typically address flow and transport based on the Darcy's law as a function of a pressure gradient and a medium-dependent permeability parameter. Additional macroscopic constitutes describe porosity, and permeability changes during the migration of a suspension through porous media. However, most of them rely on empirical correlations, which often need to be recalibrated for each application. Grain-scale modeling can be used to gain insight into scale dependence of continuum macroscale parameters. A finite element numerical solution of the Navier-Stokes equations for fluid flow together with Lagrange multiplier technique for solid particles was applied to the simulation of soil filtration in the filter layers of gravity dam. The numerical approach was validated through comparison of numerical simulations with the experimental results of base soil particle clogging in the filter layers performed at ERDC. The numerical simulation correctly predicted flow and pressure decay due to particle clogging. The base soil particle distribution was almost identical to those measured in the laboratory experiment. It is believed that the agreement between simulations and experimental data demonstrates the applicability of the proposed approach for prediction of the soil transport and clogging in embankment dams. To get more precise understanding of

Carbofuran biodegradation in brackish groundwater and its effect on the hydraulic properties of the porous medium

Science.gov (United States)

Amiaz, Yanai; Ronen, Zeev; Adar, Eilon; Weisbrod, Noam

2015-04-01

A chalk fractured aquitard beneath an industrial site is subjected to intense contamination due to percolation of contaminants from the different facilities operating at the site. In order to reduce further contamination, draining trenches were excavated and filled with coarse gravel (3-4 cm in diameter) forming a porous medium, to which the contaminated groundwater discharges from the fractures surrounding the trenches. This research is aimed at establishing a biodegrading process of high efficiency and performance within the draining trenches. The research includes both field and laboratory experiments. An experimental setup of five columns (50 cm length and 4.5 cm in diameter) was constructed under highly controlled conditions. Over the course of the experiments, the columns were filled with different particle sizes and placed in a temperature controlled chamber. Filtered groundwater (0.2 µm) from the site groundwater, enriched by a model contaminant carbofuran (CRF), was injected to the columns; as two of the columns were inoculated by CRF degrading microorganisms native in the site's groundwater, two columns were inoculated by CRF degrading bacteria from the external environment, and one column was used as a control. During the experiment, measurements were taken from different locations along each column. These include: (a) CRF concentration and (b) hydraulic pressure and solution viscosity (in order to obtain the changes in permeability). A tracer test using uranine was carried out in parallel, in order to obtain the changes in hydraulic parameters. Correlating CRF concentration variations to changes of hydraulic parameters enable the deduction due to the effect that biological activity (under different temperature regimes) has on the hydraulic properties of the porous medium and its effect on the process of contaminant groundwater bodies' remediation. Preliminary results suggest that although biodegradation occurs, microbial activity has minor effect on

Hydrodynamic calculation of a filter sand bed type used in the containment venting systems

International Nuclear Information System (INIS)

Cuevas V, D.; Sainz M, E.; Ortiz V, J.

2015-09-01

The filtered venting of the containment has been adopted in European countries to mitigate the consequences of excess pressure containment during a severe accident. When venting has taken place, the fission products are released directly into the environment, unless a filter on the same path is placed, so that various types of filters are used to trap the fission products. The venting filters of the containment currently installed use different filtration technologies that involve more than one medium. Those using water as the first stage of filtration are called wet systems and are equipped with additional steps to remove water drops and fine aerosols emissions. And even they may also be equipped with an element containing certain absorption means for the filtration of gaseous iodine species. Other designs based on filtration of deep bed as the primary retention step; called dry filters, use filtration media of metal fiber, ceramic or sand to trap aerosols. This paper evaluates the hydraulic characteristics of the filter sand bed type designed by EDF as a candidate to be installed in the containment of BWR Mark II (type of primary containment of the nuclear power plant of Laguna Verde). The evaluation of filter sand bed type was performed using the software package of open source OpenFOAM. Models of each zone of the filtered device were generated and through a series of parametric calculations of computational fluid mechanics relevant hydrodynamic characteristics of the device were obtained, such as pressure drops against mass flow rate and pressure fields and speed at different operating conditions. On the other hand, the model validation of the sand bed filter when comparing the results of experimental tests on a sand column of PITEAS program (1985-1986) against OpenFOAM simulation was realized. The results are very close to those obtained experimentally. (Author)

Muscle activation when performing the chest press and shoulder press on a stable bench vs. a Swiss ball.

Science.gov (United States)

Uribe, Brandon P; Coburn, Jared W; Brown, Lee E; Judelson, Daniel A; Khamoui, Andy V; Nguyen, Diamond

2010-04-01

The aim of this study was to examine the effects of a stable surface (bench) vs. an unstable surface (Swiss ball) on muscle activation when performing the dumbbell chest press and shoulder press. Sixteen healthy men (24.19 +/- 2.17 years) performed 1 repetition maximum (1RM) tests for the chest press and shoulder press on a stable surface. A minimum of 48 hours post 1RM, subjects returned to perform 3 consecutive repetitions each of the chest press and shoulder press at 80% 1RM under 4 different randomized conditions (chest press on bench, chest press on Swiss ball, shoulder press on bench, shoulder press on Swiss ball). Electromyography was used to assess muscle activation of the anterior deltoid, pectoralis major, and rectus abdominus. The results revealed no significant difference in muscle activation between surface types for either exercise. This suggests that using an unstable surface neither improves nor impairs muscle activation under the current conditions. Coaches and other practitioners can expect similar muscle activation when using a Swiss ball vs. a bench.

Hydraulic design development of Xiluodu Francis turbine

International Nuclear Information System (INIS)

Wang, Y L; Li, G Y; Shi, Q H; Wang, Z N

2012-01-01

Hydraulic optimization design with CFD (Computational Fluid Dynamics) method, hydraulic optimization measures and model test results in the hydraulic development of Xiluodu hydropower station by DFEM (Dongfang Electric Machinery) of DEC (Dongfang Electric Corporation) of China were analyzed in this paper. The hydraulic development conditions of turbine, selection of design parameter, comparison of geometric parameters and optimization measure of turbine flow components were expatiated. And the measures of improving turbine hydraulic performance and the results of model turbine acceptance experiment were discussed in details.

Genotypic variation in tolerance to drought stress is highly coordinated with hydraulic conductivity-photosynthesis interplay and aquaporin expression in field-grown mulberry (Morus spp.).

Science.gov (United States)

Reddy, Kanubothula Sitarami; Sekhar, Kalva Madhana; Reddy, Attipalli Ramachandra

2017-07-01

Hydraulic conductivity quantifies the efficiency of a plant to transport water from root to shoot and is a major constriction on leaf gas exchange physiology. Mulberry (Morus spp.) is the most economically important crop for sericulture industry. In this study, we demonstrate a finely coordinated control of hydraulic dynamics on leaf gas exchange characteristics in 1-year-old field-grown mulberry genotypes (Selection-13 (S13); Kollegal Local (KL) and Kanva-2 (K2)) subjected to water stress by withholding water for 20 days and subsequent recovery for 7 days. Significant variations among three mulberry genotypes have been recorded in net photosynthetic rates (Pn), stomatal conductance and sap flow rate, as well as hydraulic conductivity in stem (KS) and leaf (KL). Among three genotypes, S13 showed significantly high rates of Pn, KS and KL both in control as well as during drought stress (DS) and recovery, providing evidence for superior drought-adaptive strategies. The plant water hydraulics-photosynthesis interplay was finely coordinated with the expression of certain key aquaporins (AQPs) in roots and leaves. Our data clearly demonstrate that expression of certain AQPs play a crucial role in hydraulic dynamics and photosynthetic carbon assimilation during DS and recovery, which could be effectively targeted towards mulberry improvement programs for drought adaptation. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Design Characteristics and Tobacco Metal Concentrations in Filtered Cigars.

Science.gov (United States)

Caruso, Rosalie V; O'Connor, Richard J; Travers, Mark J; Delnevo, Cristine D; Stephens, W Edryd

2015-11-01

While U.S. cigarette consumption has declined, cigar use has steadily increased, for reasons including price compared to cigarettes and the availability of filtered varieties resembling cigarettes, and flavors that have been banned in cigarettes (excluding menthol). Little published data exists on the design characteristics of such cigars. A variety of filtered cigar brands were tested for design characteristics such as whole cigar weight, ventilation, and per-cigar tobacco weight. Cigar sticks were then sent to the University of St. Andrews for metal concentration testing of As, Pb, Cr, Ni, and Cd. Large and small cigars were statistically different between cigar weight (p ≤ .001), per-cigar tobacco weight (p = .001), rod diameter (p = .006), and filter diameter (p = .012). The differences in mean ventilation (overall mean = 19.6%, min. = 0.84%, max. = 57.6%) across filtered cigar brands were found to be statistically significant (p = .031), and can be compared to the ventilation of the average of 2013 U.S. Marlboro Red, Gold, and Silver packs at 29% ventilation. There were no significant differences for metal concentrations between cigar types (p = .650), with Pb and As levels being similar to U.S. 2009 cigarette concentrations, Cd cigar levels being slightly higher, and Cr and Ni levels much lower than cigarette levels. With cigar use rising, and filtered cigars displaying substantial similarities to filtered cigarettes, more research on product characteristics is warranted. Future plans include testing tobacco alkaloid and more observation of cigar weight for tax bracket purposes. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Sensory Pollution from Bag Filters, Carbon Filters and Combinations

DEFF Research Database (Denmark)

Bekö, Gabriel; Clausen, Geo; Weschler, Charles J.

2008-01-01

by an upstream pre-filter (changed monthly), an EU7 filter protected by an upstream activated carbon (AC) filter, and EU7 filters with an AC filter either downstream or both upstream and downstream. In addition, two types of stand-alone combination filters were evaluated: a bag-type fiberglass filter...... that contained AC and a synthetic fiber cartridge filter that contained AC. Air that had passed through used filters was most acceptable for those sets in which an AC filter was used downstream of the particle filter. Comparable air quality was achieved with the stand-alone bag filter that contained AC...

Investing in a Large Stretch Press

Science.gov (United States)

Choate, M.; Nealson, W.; Jay, G.; Buss, W.

1986-01-01

Press for forming large aluminum parts from plates provides substantial economies. Study assessed advantages and disadvantages of investing in large stretch-forming press, and also developed procurement specification for press.

Uncertainty in hydraulic tests in fractured rock

International Nuclear Information System (INIS)

Ji, Sung-Hoon; Koh, Yong-Kwon

2014-01-01

Interpretation of hydraulic tests in fractured rock has uncertainty because of the different hydraulic properties of a fractured rock to a porous medium. In this study, we reviewed several interesting phenomena which show uncertainty in a hydraulic test at a fractured rock and discussed their origins and the how they should be considered during site characterisation. Our results show that the estimated hydraulic parameters of a fractured rock from a hydraulic test are associated with uncertainty due to the changed aperture and non-linear groundwater flow during the test. Although the magnitude of these two uncertainties is site-dependent, the results suggest that it is recommended to conduct a hydraulic test with a little disturbance from the natural groundwater flow to consider their uncertainty. Other effects reported from laboratory and numerical experiments such as the trapping zone effect (Boutt, 2006) and the slip condition effect (Lee, 2014) can also introduce uncertainty to a hydraulic test, which should be evaluated in a field test. It is necessary to consider the way how to evaluate the uncertainty in the hydraulic property during the site characterisation and how to apply it to the safety assessment of a subsurface repository. (authors)

AUPress: A Comparison of an Open Access University Press with Traditional Presses

Science.gov (United States)

McGreal, Rory; Chen, Nian-Shing

2011-01-01

This study is a comparison of AUPress with three other traditional (non-open access) Canadian university presses. The analysis is based on the rankings that are correlated with book sales on Amazon.com and Amazon.ca. Statistical methods include the sampling of the sales ranking of randomly selected books from each press. The results of one-way…

Professional WordPress design and development

CERN Document Server

Williams, Brad; Stern, Hal

2014-01-01

The highest rated WordPress development and design book on the market is back with an all new third edition. Professional WordPress is the only WordPress book targeted to developers, with advanced content that exploits the full functionality of the most popular CMS in the world. Fully updated to align with WordPress 4.1, this edition has updated examples with all new screenshots, and full exploration of additional tasks made possible by the latest tools and features. You will gain insight into real projects that currently use WordPress as an application framework, as well as the basic usage a

Proceedings of the 1991 national conference on hydraulic engineering

International Nuclear Information System (INIS)

Shane, R.M.

1991-01-01

This book contains the proceedings of the 1991 National Conference of Hydraulic Engineering. The conference was held in conjunction with the International Symposium on Ground Water and a Software Exchange that facilitated exchange of information on recent software developments of interest to hydraulic engineers. Also included in the program were three mini-symposia on the Exclusive Economic Zone, Data Acquisition, and Appropriate Technology. Topics include sedimentation; appropriate technology; exclusive economic zone hydraulics; hydraulic data acquisition and display; innovative hydraulic structures and water quality applications of hydraulic research, including the hydraulics of aerating turbines; wetlands; hydraulic and hydrologic extremes; highway drainage; overtopping protection of dams; spillway design; coastal and estuarine hydraulics; scale models; computation hydraulics; GIS and expert system applications; watershed response to rainfall; probabilistic approaches; and flood control investigations

BuddyPress theme development

CERN Document Server

Lister, Tammie

2013-01-01

This book is a hands-on tutorial guide to using BuddyPress.This book is great for designers and developers who are looking to learn how to develop BuddyPress themes. It's assumed that the reader has some understanding of Wordpress and is familiar with CSS and HTML.

Undular Hydraulic Jump

Directory of Open Access Journals (Sweden)

Oscar Castro-Orgaz

2015-04-01

Full Text Available The transition from subcritical to supercritical flow when the inflow Froude number Fo is close to unity appears in the form of steady state waves called undular hydraulic jump. The characterization of the undular hydraulic jump is complex due to the existence of a non-hydrostatic pressure distribution that invalidates the gradually-varied flow theory, and supercritical shock waves. The objective of this work is to present a mathematical model for the undular hydraulic jump obtained from an approximate integration of the Reynolds equations for turbulent flow assuming that the Reynolds number R is high. Simple analytical solutions are presented to reveal the physics of the theory, and a numerical model is used to integrate the complete equations. The limit of application of the theory is discussed using a wave breaking condition for the inception of a surface roller. The validity of the mathematical predictions is critically assessed using physical data, thereby revealing aspects on which more research is needed

Treatment of suspended solids and heavy metals from urban stormwater runoff by a tree box filter.

Science.gov (United States)

Geronimo, F K F; Maniquiz-Redillas, M C; Tobio, J A S; Kim, L H

2014-01-01

Particulates, inorganic and toxic constituents are the most common pollutants associated with urban stormwater runoff. Heavy metals such as chromium, nickel, copper, zinc, cadmium and lead are found to be in high concentration on paved roads or parking lots due to vehicle emissions. In order to control the rapid increase of pollutant loads in stormwater runoff, the Korean Ministry of Environment proposed the utilization of low impact developments. One of these was the application of tree box filters that act as a bioretention treatment system which executes filtration and sorption processes. In this study, a tree box filter located adjacent to an impervious parking lot was developed to treat suspended solids and heavy metal concentrations from urban stormwater runoff. In total, 11 storm events were monitored from July 2010 to August 2012. The results showed that the tree box filter was highly effective in removing particulates (up to 95%) and heavy metals (at least 70%) from the urban stormwater runoff. Furthermore, the tree box filter was capable of reducing the volume runoff by 40% at a hydraulic loading rate of 1 m/day and below.

Birth of a hydraulic jump

Science.gov (United States)

Duchesne, Alexis; Bohr, Tomas; Andersen, Anders

2017-11-01

The hydraulic jump, i.e., the sharp transition between a supercritical and a subcritical free-surface flow, has been extensively studied in the past centuries. However, ever since Leonardo da Vinci asked it for the first time, an important question has been left unanswered: How does a hydraulic jump form? We present an experimental and theoretical study of the formation of stationary hydraulic jumps in centimeter wide channels. Two starting situations are considered: The channel is, respectively, empty or filled with liquid, the liquid level being fixed by the wetting properties and the boundary conditions. We then change the flow-rate abruptly from zero to a constant value. In an empty channel, we observe the formation of a stationary hydraulic jump in a two-stage process: First, the channel fills by the advancing liquid front, which undergoes a transition from supercritical to subcritical at some position in the channel. Later the influence of the downstream boundary conditions makes the jump move slowly upstream to its final position. In the pre-filled channel, the hydraulic jump forms at the injector edge and then moves downstream to its final position.

Divergences in hydraulic architecture form an important basis for niche differentiation between diploid and polyploid Betula species in NE China.

Science.gov (United States)

Zhang, Wei-Wei; Song, Jia; Wang, Miao; Liu, Yan-Yan; Li, Na; Zhang, Yong-Jiang; Holbrook, N Michele; Hao, Guang-You

2017-05-01

Habitat differentiation between polyploid and diploid plants are frequently observed, with polyploids usually occupying more stressed environments. In woody plants, polyploidization can greatly affect wood characteristics but knowledge of its influences on xylem hydraulics is scarce. The four Betula species in NE China, representing two diploids and two polyploids with obvious habitat differentiation, provide an exceptional study system for investigating the impact of polyploidization on environmental adaptation of trees from the point view of xylem hydraulics. To test the hypothesis that changes in hydraulic architecture play an important role in determining their niche differentiation, we measured wood structural traits at both the tissue and pit levels and quantified xylem water transport efficiency and safety in these species. The two polyploids had significantly larger hydraulic weighted mean vessel diameters than the two diploids (45.1 and 45.5 vs 25.9 and 24.5 μm) although the polyploids are occupying more stressed environments. As indicated by more negative water potentials corresponding to 50% loss of stem hydraulic conductivities, the two polyploids exhibited significantly higher resistance to drought-induced embolism than the two diploids (-5.23 and -5.05 vs -3.86 and -3.13 MPa) despite their larger vessel diameters. This seeming discrepancy is reconciled by distinct characteristics favoring greater embolism resistance at the pit level in the two polyploid species. Our results showed clearly that the two polyploid species have remarkably different pit-level anatomical traits favoring greater hydraulic safety than their congeneric diploid species, which have likely contributed to the abundance of polyploid birches in more stressed habitats; however, less porous inter-conduit pits together with a reduced leaf to sapwood area may have compromised their competitiveness under more favorable conditions. Contrasts in hydraulic architecture between diploid and

Conférence de presse | Press Conference

CERN Multimedia

CERN. Geneva; Bejar Alonso, Isabel

2018-01-01

10:00-11:00 Conférence de presse en présence de Lucio Rossi, chef du projet LHC à Haute Luminosité et Isabel Bejar Alonso, chargée de la configuration, de la qualité et des ressources du projet LHC à Haute Luminosité.

Hydraulic Hybrid Fleet Vehicle Testing | Transportation Research | NREL

Science.gov (United States)

Hydraulic Hybrid Fleet Vehicle Evaluations Hydraulic Hybrid Fleet Vehicle Evaluations How Hydraulic Hybrid Vehicles Work Hydraulic hybrid systems can capture up to 70% of the kinetic energy that would -pressure reservoir to a high-pressure accumulator. When the vehicle accelerates, fluid in the high-pressure

The performance of BAF using natural zeolite as filter media under conditions of low temperature and ammonium shock load

International Nuclear Information System (INIS)

He Shengbing; Xue Gang; Kong Hainan

2007-01-01

Natural zeolite and expanded clay were used as filter media for biological aerated filter (BAF) to treat municipal wastewater in parallel in whole three test stages. The stage one test results revealed that zeolite BAF and expanded clay BAF have COD and NH 3 -N removals in the range of 84.63-93.11%, 85.74-96.26%, 82.34-93.71%, and 85.06-93.2%, respectively, under the conditions of water temperature of 20-25 deg. C and hydraulic load of 2-3 m 3 /(m 2 h). At the following stage two, the influent NH 3 -N concentration was increased to about double value of the stage one, and it was investigated that the effluent NH 3 -N of expanded clay BAF increased significantly and then gradually restored to normal condition in 2 weeks, while the effluent NH 3 -N of zeolite BAF kept stable. At stage three, the low reactor temperature has also different effects on these two BAFs, under conditions of water temperature of 7-10 deg. C, hydraulic load of 2-3 m 3 /(m 2 h), zeolite BAF and expanded clay BAF have COD and NH 3 -N removals in the range of 74.5-88.47% (average of 81.57%), 71.73-88.49% (average of 81.06%), 71.91-87.76% (average of 80.49%), and 38.41-77.17% (average of 65.42%), respectively. Three stages test results indicated that the zeolite BAF has a stronger adaptability to NH 3 -N shock load and low temperature compared to expanded clay BAF. In addition, the detection of the amounts of heterobacteria and nitrobacteria of two biological aerated filters in three stages also showed the zeolite filter media was more suitable to the attached growth of nitrobacteria, which is helpful to the improvement of nitrification performance in zeolite BAF

Filter arrays

Science.gov (United States)

Page, Ralph H.; Doty, Patrick F.

2017-08-01

The various technologies presented herein relate to a tiled filter array that can be used in connection with performance of spatial sampling of optical signals. The filter array comprises filter tiles, wherein a first plurality of filter tiles are formed from a first material, the first material being configured such that only photons having wavelengths in a first wavelength band pass therethrough. A second plurality of filter tiles is formed from a second material, the second material being configured such that only photons having wavelengths in a second wavelength band pass therethrough. The first plurality of filter tiles and the second plurality of filter tiles can be interspersed to form the filter array comprising an alternating arrangement of first filter tiles and second filter tiles.

Hybrid Robust Control Law with Disturbance Observer for High-Frequency Response Electro-Hydraulic Servo Loading System

Directory of Open Access Journals (Sweden)

Zhiqing Sheng

2016-04-01

Full Text Available Addressing the simulating issue of the helicopter-manipulating booster aerodynamic load with high-frequency dynamic load superimposed on a large static load, this paper studies the design of the robust controller for the electro-hydraulic loading system to realize the simulation of this kind of load. Firstly, the equivalent linear model of the electro-hydraulic loading system under assumed parameter uncertainty is established. Then, a hybrid control scheme is proposed for the loading system. This control scheme consists of a constant velocity feed-forward compensator, a robust inner loop compensator based on disturbance observer and a robust outer loop feedback controller. The constant velocity compensator eliminates most of the extraneous force at first, and then the double-loop cascade composition control strategy is employed to design the compensated system. The disturbance observer–based inner loop compensator further restrains the disturbances including the remaining extraneous force, and makes the actual plant tracking a nominal model approximately in a certain frequency range. The robust outer loop controller achieves the desired force-tracking performance, and guarantees system robustness in the high frequency region. The optimized low-pass filter Q(s is designed by using the H∞ mixed sensitivity optimization method. The simulation results show that the proposed hybrid control scheme and controller can effectively suppress the extraneous force and improve the robustness of the electro-hydraulic loading system.

Hydraulics and pneumatics

CERN Document Server

Parr, Andrew

2006-01-01

Nearly all industrial processes require objects to be moved, manipulated or subjected to some sort of force. This is frequently accomplished by means of electrical equipment (such as motors or solenoids), or via devices driven by air (pneumatics) or liquids (hydraulics).This book has been written by a process control engineer as a guide to the operation of hydraulic and pneumatic systems for all engineers and technicians who wish to have an insight into the components and operation of such a system.This second edition has been fully updated to include all recent developments su

Thermal-hydraulic unreliability of passive systems

International Nuclear Information System (INIS)

Tzanos, C.P.; Saltos, N.T.

1995-01-01

Advanced light water reactor designs like AP600 and the simplified boiling water reactor (SBWR) use passive safety systems for accident prevention and mitigation. Because these systems rely on natural forces for their operation, their unavailability due to hardware failures and human error is significantly smaller than that of active systems. However, the coolant flows predicted to be delivered by these systems can be subject to significant uncertainties, which in turn can lead to a significant uncertainty in the predicted thermal-hydraulic performance of the plant under accident conditions. Because of these uncertainties, there is a probability that an accident sequence for which a best estimate thermal-hydraulic analysis predicts no core damage (success sequence) may actually lead to core damage. For brevity, this probability will be called thermal-hydraulic unreliability. The assessment of this unreliability for all the success sequences requires very expensive computations. Moreover, the computational cost increases drastically as the required thermal-hydraulic reliability increases. The required computational effort can be greatly reduced if a bounding approach can be used that either eliminates the need to compute thermal-hydraulic unreliabilities, or it leads to the analysis of a few bounding sequences for which the required thermal-hydraulic reliability is relatively small. The objective of this paper is to present such an approach and determine the order of magnitude of the thermal-hydraulic unreliabilities that may have to be computed

WordPress all-in-one for dummies

CERN Document Server

Sabin-Wilson, Lisa

2013-01-01

Top WordPress guide, now fully updated for the latest WordPress release! This updated new edition comprises one of the largest collections of practical intermediate to advanced information on WordPress. Fully updated for the latest WordPress release, this in-depth book covers it all, from setting up your software to publishing your site, using SEO and social media, developing and using plug-ins, running multiple sites with WordPress, and more. Veteran author Lisa Sabin-Wilson is a top authority on WordPress, and she and her co-authors pack this book with essential and easy-to-follo

Characteristics of Air Entrainment in Hydraulic Jump

Science.gov (United States)

Albarkani, M. S. S.; Tan, L. W.; Al-Gheethi, A.

2018-04-01

The characteristics of hydraulic jump, especially the air entrainment within jump is still not properly understood. Therefore, the current work aimed to determine the size and number of air entrainment formed in hydraulic jump at three different Froude numbers and to obtain the relationship between Froude number with the size and number of air entrainment in hydraulic jump. Experiments of hydraulic jump were conducted in a 10 m long and 0.3 m wide Armfield S6MKII glass-sided tilting flume. Hydraulic jumps were produced by flow under sluice gate with varying Froude number. The air entrainment of the hydraulic jump was captured with a Canon Power Shot SX40 HS digital camera in video format at 24 frames per second. Three discharges have been considered, i.e. 0.010 m3/s, 0.011 m3/s, and 0.013 m3/s. For hydraulic jump formed in each discharge, 32 frames were selected for the purpose of analysing the size and number of air entrainment in hydraulic jump. The results revealed that that there is a tendency to have greater range in sizes of air bubbles as Fr1 increases. Experiments with Fr1 = 7.547. 7.707, and 7.924 shown that the number of air bubbles increases exponentially with Fr1 at a relationship of N = 1.3814 e 0.9795Fr1.

Rapid hydraulic recovery in Eucalyptus pauciflora after drought: linkages between stem hydraulics and leaf gas exchange.

Science.gov (United States)

Martorell, Sebastià; Diaz-Espejo, Antonio; Medrano, Hipólito; Ball, Marilyn C; Choat, Brendan

2014-03-01

In woody plants, photosynthetic capacity is closely linked to rates at which the plant hydraulic system can supply water to the leaf surface. Drought-induced embolism can cause sharp declines in xylem hydraulic conductivity that coincide with stomatal closure and reduced photosynthesis. Recovery of photosynthetic capacity after drought is dependent on restored xylem function, although few data exist to elucidate this coordination. We examined the dynamics of leaf gas exchange and xylem function in Eucalyptus pauciflora seedlings exposed to a cycle of severe water stress and recovery after re-watering. Stomatal closure and leaf turgor loss occurred at water potentials that delayed the extensive spread of embolism through the stem xylem. Stem hydraulic conductance recovered to control levels within 6 h after re-watering despite a severe drought treatment, suggesting an active mechanism embolism repair. However, stomatal conductance did not recover after 10 d of re-watering, effecting tighter control of transpiration post drought. The dynamics of recovery suggest that a combination of hydraulic and non-hydraulic factors influenced stomatal behaviour post drought. © 2013 John Wiley & Sons Ltd.

Estimating Hydraulic Resistance for Floodplain Mapping and Hydraulic Studies from High-Resolution Topography: Physical and Numerical Simulations

Science.gov (United States)

Minear, J. T.

2017-12-01

One of the primary unknown variables in hydraulic analyses is hydraulic resistance, values for which are typically set using broad assumptions or calibration, with very few methods available for independent and robust determination. A better understanding of hydraulic resistance would be highly useful for understanding floodplain processes, forecasting floods, advancing sediment transport and hydraulic coupling, and improving higher dimensional flood modeling (2D+), as well as correctly calculating flood discharges for floods that are not directly measured. The relationship of observed features to hydraulic resistance is difficult to objectively quantify in the field, partially because resistance occurs at a variety of scales (i.e. grain, unit and reach) and because individual resistance elements, such as trees, grass and sediment grains, are inherently difficult to measure. Similar to photogrammetric techniques, Terrestrial Laser Scanning (TLS, also known as Ground-based LiDAR) has shown great ability to rapidly collect high-resolution topographic datasets for geomorphic and hydrodynamic studies and could be used to objectively quantify the features that collectively create hydraulic resistance in the field. Because of its speed in data collection and remote sensing ability, TLS can be used both for pre-flood and post-flood studies that require relatively quick response in relatively dangerous settings. Using datasets collected from experimental flume runs and numerical simulations, as well as field studies of several rivers in California and post-flood rivers in Colorado, this study evaluates the use of high-resolution topography to estimate hydraulic resistance, particularly from grain-scale elements. Contrary to conventional practice, experimental laboratory runs with bed grain size held constant but with varying grain-scale protusion create a nearly twenty-fold variation in measured hydraulic resistance. The ideal application of this high-resolution topography

Press to compress contaminated wastes drums

International Nuclear Information System (INIS)

Prevost, J.

1993-01-01

This patent describes a press for contaminated wastes drums pressing. The press is made of a structure comprising a base and an upper stringer bind to the base by vertical bearers, a compression system comprising a main cylinder and a ram, connected to the upper stringer

ISS Expedition 08 Press Kit

Data.gov (United States)

National Aeronautics and Space Administration — Press kit for ISS mission Expedition 08 from 10/2003-04/2004. Press kits contain information about each mission overview, crew, mission timeline, benefits, and media...

Hydraulic gradients in rock aquifers

International Nuclear Information System (INIS)

Dahlblom, P.

1992-05-01

This report deals with fractured rock as a host for deposits of hazardous waste. In this context the rock, with its fractures containing moving groundwater, is called the geological barrier. The desired properties of the geological barrier are low permeability to water, low hydraulic gradients and ability to retain matter dissolved in the water. The hydraulic gradient together with the permeability and the porosity determines the migration velocity. Mathematical modelling of the migration involves calculation of the water flow and the hydrodynamic dispersion of the contaminant. The porous medium approach can be used to calculate mean flow velocities and hydrodynamic dispersion of a large number of fractures are connected, which means that a large volume have to be considered. It is assumed that the porous medium approach can be applied, and a number of idealized examples are shown. It is assumed that the groundwater table is replenished by percolation at a constant rate. One-dimensional analytical calculations show that zero hydraulic gradients may exist at relatively large distance from the coast. Two-dimensional numerical calculations show that it may be possible to find areas with low hydraulic gradients and flow velocities within blocks surrounded by areas with high hydraulic conductivity. (au)

Inherent Limitations of Hydraulic Tomography

Science.gov (United States)

Bohling, Geoffrey C.; Butler, J.J.

2010-01-01

We offer a cautionary note in response to an increasing level of enthusiasm regarding high-resolution aquifer characterization with hydraulic tomography. We use synthetic examples based on two recent field experiments to demonstrate that a high degree of nonuniqueness remains in estimates of hydraulic parameter fields even when those estimates are based on simultaneous analysis of a number of carefully controlled hydraulic tests. We must, therefore, be careful not to oversell the technique to the community of practicing hydrogeologists, promising a degree of accuracy and resolution that, in many settings, will remain unattainable, regardless of the amount of effort invested in the field investigation. No practically feasible amount of hydraulic tomography data will ever remove the need to regularize or bias the inverse problem in some fashion in order to obtain a unique solution. Thus, along with improving the resolution of hydraulic tomography techniques, we must also strive to couple those techniques with procedures for experimental design and uncertainty assessment and with other more cost-effective field methods, such as geophysical surveying and, in unconsolidated formations, direct-push profiling, in order to develop methods for subsurface characterization with the resolution and accuracy needed for practical field applications. Copyright ?? 2010 The Author(s). Journal compilation ?? 2010 National Ground Water Association.

MATLAB algorithm to implement soil water data assimilation with the Ensemble Kalman Filter using HYDRUS.

Science.gov (United States)

Valdes-Abellan, Javier; Pachepsky, Yakov; Martinez, Gonzalo

2018-01-01

Data assimilation is becoming a promising technique in hydrologic modelling to update not only model states but also to infer model parameters, specifically to infer soil hydraulic properties in Richard-equation-based soil water models. The Ensemble Kalman Filter method is one of the most widely employed method among the different data assimilation alternatives. In this study the complete Matlab© code used to study soil data assimilation efficiency under different soil and climatic conditions is shown. The code shows the method how data assimilation through EnKF was implemented. Richards equation was solved by the used of Hydrus-1D software which was run from Matlab. •MATLAB routines are released to be used/modified without restrictions for other researchers•Data assimilation Ensemble Kalman Filter method code.•Soil water Richard equation flow solved by Hydrus-1D.

Experimentation on the anaerobic filter reactor for biogas production using rural domestic wastewater

Science.gov (United States)

Leju Celestino Ladu, John; Lü, Xi-wu; Zhong, Zhaoping

2017-08-01

The biogas production from anaerobic filter (AF) reactor was experimented in Taihu Lake Environmental Engineering Research Center of Southeast University, Wuxi, China. Two rounds of experimental operations were conducted in a laboratory scale at different Hydraulic retention time (HRT) and wastewater temperature. The biogas production rate during the experimentation was in the range of 4.63 to 11.78 L/d. In the first experimentation, the average gas production rate was 10.08 L/d, and in the second experimentation, the average gas production rate was 4.97 L/d. The experimentation observed the favorable Hydraulic Retention Time and wastewater temperature in AF was three days and 30.95°C which produced the gas concentration of 11.78 L/d. The HRT and wastewater temperature affected the efficiency of the AF process on the organic matter removal and nutrients removal as well. It can be deduced from the obtained results that HRT and wastewater temperature directly affects the efficiency of the AF reactor in biogas production. In conclusion, anaerobic filter treatment of organic matter substrates from the rural domestic wastewater increases the efficiency of the AF reactor on biogas production and gives a number of benefits for the management of organic wastes as well as reduction in water pollution. Hence, the operation of the AF reactor in rural domestic wastewater treatment can play an important element for corporate economy of the biogas plant, socio-economic aspects and in the development of effective and feasible concepts for wastewater management, especially for people in rural low-income areas.

14 CFR 33.72 - Hydraulic actuating systems.

Science.gov (United States)

2010-01-01

... AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.72 Hydraulic actuating systems. Each hydraulic actuating system must function properly under all conditions in which the... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic actuating systems. 33.72 Section...

Bullying the media : Cultural and climato-economic readings of press repression versus press freedom

NARCIS (Netherlands)

Van de Vliert, E.

Journalists and media assistants in many places are murdered, imprisoned, censored, threatened, and similarly harrassed. Here I document that, and explain why, there are three climato-economic niches of press repression versus press freedom as part of broader syndromes of national culture. A

Digital Simulation of a Hybrid Active Filter - An Active Filter in Series with a Shunt Passive Filter

OpenAIRE

Sitaram, Mahesh I; Padiyar, KR; Ramanarayanan, V

1998-01-01

Active filters have long been in use for the filtering of power system load harmonics. In this paper, the digital simulation results of a hybrid active power filter system for a rectifier load are presented. The active filter is used for filtering higher order harmonics as the dominant harmonics are filtered by the passive filter. This reduces the rating of the active filter significantly. The DC capacitor voltage of the active filter is controlled using a PI controller.

Hydraulic Structures

Data.gov (United States)

Department of Homeland Security — This table is required whenever hydraulic structures are shown in the flood profile. It is also required if levees are shown on the FIRM, channels containing the...

Activation of Selected Core Muscles during Pressing

Directory of Open Access Journals (Sweden)

Thomas W. Nesser

2015-10-01

Full Text Available Introduction: Unstable surface training is often used to activate core musculature during resistance training. Unfortunately, unstable surface training is risky and leads to detraining. Purpose: The purpose of this study was to determine core muscle activation during stable surface ground-based lifts. Methods: Fourteen recreational trained and former NCAA DI athletes (weight 84.2 ± 13.3 kg; height 176.0 ± 9.5 cm; age 20.9 ± 2.0 years volunteered for participation. Subjects completed two ground-based lifts: overhead press and push-press. Surface EMG was recorded from 4 muscles on the right side of the body (Rectus Abdominus (RA, External Oblique (EO, Transverse Abdominus (TA, and Erector Spinae (ES. Results: Paired sample T-tests identified significant muscle activation differences between the overhead press and the push-press included ES and EO. Average and peak EMG for ES was significantly greater in push-press (P<0.01. Anterior displacement of COP was significantly greater in push-press compared to overhead press during the eccentric phase. Conclusion: The push-press was identified as superior in core muscle activation when compared to the overhead pressing exercise. Keywords: torso, stability, weight lifting, resistance training

Hydraulic pitch control system for wind turbines: Advanced modeling and verification of an hydraulic accumulator

DEFF Research Database (Denmark)

Irizar, Victor; Andreasen, Casper Schousboe

2017-01-01

Hydraulic pitch systems provide robust and reliable control of power and speed of modern wind turbines. During emergency stops, where the pitch of the blades has to be taken to a full stop position to avoid over speed situations, hydraulic accumulators play a crucial role. Their efficiency...... and capability of providing enough energy to rotate the blades is affected by thermal processes due to the compression and decompression of the gas chamber. This paper presents an in depth study of the thermodynamical processes involved in an hydraulic accumulator during operation, and how they affect the energy...

Hydraulics and pneumatics a technician's and engineer's guide

CERN Document Server

Parr, Andrew

1991-01-01

Hydraulics and Pneumatics: A Technician's and Engineer's Guide provides an introduction to the components and operation of a hydraulic or pneumatic system. This book discusses the main advantages and disadvantages of pneumatic or hydraulic systems.Organized into eight chapters, this book begins with an overview of industrial prime movers. This text then examines the three different types of positive displacement pump used in hydraulic systems, namely, gear pumps, vane pumps, and piston pumps. Other chapters consider the pressure in a hydraulic system, which can be quickly and easily controlled

Applicability estimation of flowmeter logging for detecting hydraulic pass

International Nuclear Information System (INIS)

Miyakawa, Kimio; Tanaka, Yasuji; Tanaka, Kazuhiro

1997-01-01

Estimation of the hydraulic pass governing hydrogeological structure contributes significantly to the siting HLW repository. Flowmeter logging can detect hydraulic passes by measuring vertical flow velocity of groundwater in the borehole. We reviewed application of this logging in situ. The hydraulic pass was detected with combination of ambient flow logging, with pumping and/or injecting induced flow logging. This application showed that the flowmeter logging detected hydraulic passes conveniently and accurately compared with other hydraulic tests. Hydraulic conductivity by using flowmeter logging was assessed above 10 -6 m/sec and within one order from comparison with injection packer tests. We suggest that appropriate application of the flowmeter logging for the siting is conducted before hydraulic tests because test sections and monitoring sections are decided rationally for procurement of quantitative hydraulic data. (author)

Advantages of Oscillatory Hydraulic Tomography

Science.gov (United States)

Kitanidis, P. K.; Bakhos, T.; Cardiff, M. A.; Barrash, W.

2012-12-01

Characterizing the subsurface is significant for most hydrogeologic studies, such as those involving site remediation and groundwater resource explo¬ration. A variety of hydraulic and geophysical methods have been developed to estimate hydraulic conductivity and specific storage. Hydraulic methods based on the analysis of conventional pumping tests allow the estimation of conductivity and storage without need for approximate petrophysical relations, which is an advantage over most geophysical methods that first estimate other properties and then infer values of hydraulic parameters. However, hydraulic methods have the disadvantage that the head-change signal decays with distance from the pumping well and thus becomes difficult to separate from noise except in close proximity to the source. Oscillatory hydraulic tomography (OHT) is an emerging technology to im¬age the subsurface. This method utilizes the idea of imposing sinusoidally varying pressure or discharge signals at several points, collecting head observations at several other points, and then processing these data in a tomographic fashion to estimate conductivity and storage coefficients. After an overview of the methodology, including a description of the most important potential advantages and challenges associated with this approach, two key promising features of the approach will be discussed. First, the signal at an observation point is orthogonal to and thus can be separated from nuisance inputs like head fluctuation from production wells, evapotranspiration, irrigation, and changes in the level of adjacent streams. Second, although the signal amplitude may be weak, one can extract the phase and amplitude of the os¬cillatory signal by collecting measurements over a longer time, thus compensating for the effect of large distance through longer sampling period.

Hydraulic power take-off for wave energy systems

DEFF Research Database (Denmark)

Christensen, Georg Kronborg

2001-01-01

Investigation and laboratory experiments with a hydraulic power conversion system for converting forces from a 2.5m diamter float to extract energy from seawaves. The test rig consists of a hydraulic wave simulator and a hydraulic point absorber. The absorber converts the incomming forces to a co...... to a continous rotation of an electric generator. The experiments document efficiencies and losses for the conversion process. The experiments are used for verification and update of a computer model.......Investigation and laboratory experiments with a hydraulic power conversion system for converting forces from a 2.5m diamter float to extract energy from seawaves. The test rig consists of a hydraulic wave simulator and a hydraulic point absorber. The absorber converts the incomming forces...

Cavitation in Hydraulic Machinery

Energy Technology Data Exchange (ETDEWEB)

Kjeldsen, M.

1996-11-01

The main purpose of this doctoral thesis on cavitation in hydraulic machinery is to change focus towards the coupling of non-stationary flow phenomena and cavitation. It is argued that, in addition to turbulence, superimposed sound pressure fluctuations can have a major impact on cavitation and lead to particularly severe erosion. For the design of hydraulic devices this finding may indicate how to further limit the cavitation problems. Chapter 1 reviews cavitation in general in the context of hydraulic machinery, emphasizing the initial cavitation event and the role of the water quality. Chapter 2 discusses the existence of pressure fluctuations for situations common in such machinery. Chapter 3 on cavitation dynamics presents an algorithm for calculating the nucleation of a cavity cluster. Chapter 4 describes the equipment used in this work. 53 refs., 55 figs.,10 tabs.

Process of preparing hydraulic cement

Energy Technology Data Exchange (ETDEWEB)

1919-12-11

A process of preparing hydraulic cement from oil shale or shale coke is characterized in that the oil shale or shale coke after the distillation is burned long and hot to liberate the usual amount of carbonic acid and then is fine ground to obtain a slow hardening hydraulic cement.

Hydraulic loop: practices using open control systems

International Nuclear Information System (INIS)

Carrasco, J.A.; Alonso, L.; Sanchez, F.

1998-01-01

The Tecnatom Hydraulic Loop is a dynamic training platform. It has been designed with the purpose of improving the work in teams. With this system, the student can obtain a full scope vision of a system. The hydraulic Loop is a part of the Tecnatom Maintenance Centre. The first objective of the hydraulic Loop is the instruction in components, process and process control using open control system. All the personal of an electric power plant can be trained in the Hydraulic Loop with specific courses. The development of a dynamic tool for tests previous to plant installations has been an additional objective of the Hydraulic Loop. The use of this platform is complementary to the use of full-scope simulators in order to debug and to analyse advanced control strategies. (Author)

Modified septic tank-anaerobic filter unit as a two-stage onsite domestic wastewater treatment system.

Science.gov (United States)

Sharma, Meena Kumari; Khursheed, Anwar; Kazmi, Absar Ahmad

2014-01-01

This study demonstrates the performance evaluation of a uniquely designed two-stage system for onsite treatment of domestic wastewater. The system consisted of two upflow anaerobic bioreactors, a modified septic tank followed by an upflow anaerobic filter, accommodated within a single cylindrical unit. The system was started up without inoculation at 24 h hydraulic retention time (HRT). It achieved a steady-state condition after 120 days. The system was observed to be remarkably efficient in removing pollutants during steady-state condition with the average removal efficiency of 88.6 +/- 3.7% for chemical oxygen demand, 86.3 +/- 4.9% for biochemical oxygen demand and 91.2 +/- 9.7% for total suspended solids. The microbial analysis revealed a high reduction (>90%) capacity of the system for indicator organism and pathogens. It also showed a very good endurance against imposed hydraulic shock load. Tracer study showed that the flow pattern was close to plug flow reactor. Mean HRT was also found to be close to the designed value.

Hydraulics submission for Middlesex County, NJ

Data.gov (United States)

Federal Emergency Management Agency, Department of Homeland Security — Hydraulics data include spatial datasets and data tables necessary for documenting the hydraulic procedures for estimating base flood elevation for a flood insurance...

Hydraulics submission for Gloucester County, NJ

Data.gov (United States)

Federal Emergency Management Agency, Department of Homeland Security — Hydraulics data include spatial datasets and data tables necessary for documenting the hydraulic procedures for estimating base flood elevation for a flood insurance...

Filter assembly for metallic and intermetallic tube filters

Science.gov (United States)

Alvin, Mary Anne; Lippert, Thomas E.; Bruck, Gerald J.; Smeltzer, Eugene E.

2001-01-01

A filter assembly (60) for holding a filter element (28) within a hot gas cleanup system pressure vessel is provided, containing: a filter housing (62), said filter housing having a certain axial length and having a peripheral sidewall, said sidewall defining an interior chamber (66); a one piece, all metal, fail-safe/regenerator device (68) within the interior chamber (66) of the filter housing (62) and/or extending beyond the axial length of the filter housing, said device containing an outward extending radial flange (71) within the filter housing for seating an essential seal (70), the device also having heat transfer media (72) disposed inside and screens (80) for particulate removal; one compliant gasket (70) positioned next to and above the outward extending radial flange of the fail-safe/regenerator device; and a porous metallic corrosion resistant superalloy type filter element body welded at the bottom of the metal fail-safe/regenerator device.

Statistically-Efficient Filtering in Impulsive Environments: Weighted Myriad Filters

Directory of Open Access Journals (Sweden)

Juan G. Gonzalez

2002-01-01

Full Text Available Linear filtering theory has been largely motivated by the characteristics of Gaussian signals. In the same manner, the proposed Myriad Filtering methods are motivated by the need for a flexible filter class with high statistical efficiency in non-Gaussian impulsive environments that can appear in practice. Myriad filters have a solid theoretical basis, are inherently more powerful than median filters, and are very general, subsuming traditional linear FIR filters. The foundation of the proposed filtering algorithms lies in the definition of the myriad as a tunable estimator of location derived from the theory of robust statistics. We prove several fundamental properties of this estimator and show its optimality in practical impulsive models such as the α-stable and generalized-t. We then extend the myriad estimation framework to allow the use of weights. In the same way as linear FIR filters become a powerful generalization of the mean filter, filters based on running myriads reach all of their potential when a weighting scheme is utilized. We derive the “normal” equations for the optimal myriad filter, and introduce a suboptimal methodology for filter tuning and design. The strong potential of myriad filtering and estimation in impulsive environments is illustrated with several examples.

Filter material charging apparatus for filter assembly for radioactive contaminants

International Nuclear Information System (INIS)

Goldsmith, J.M.; O'Nan, A. Jr.

1977-01-01

A filter charging apparatus for a filter assembly is described. The filter assembly includes a housing with at least one filter bed therein and the filter charging apparatus for adding filter material to the filter assembly includes a tank with an opening therein, the tank opening being disposed in flow communication with opposed first and second conduit means, the first conduit means being in flow communication with the filter assembly housing and the second conduit means being in flow communication with a blower means. Upon activation of the blower means, the blower means pneumatically conveys the filter material from the tank to the filter housing

Laser induced fluorescence thermometry (LIF-T) as a non-invasive temperature measurement technique for thermal hydraulic experiments

Energy Technology Data Exchange (ETDEWEB)

Strack, J.; Leung, K.; Walker, A., E-mail: strackj@mcmaster.ca [McMaster Univ., Hamilton, ON (Canada)

2014-07-01

Laser induced fluorescence (LIF) is an experimental technique whereby a scalar field in a fluid system is measured optically from the fluorescence intensity of a tracer dye following excitation by laser light. For laser induced fluorescence thermometry (LIF-T), a temperature sensitive dye is used. Through the use of a temperature sensitive tracer dye, sheet laser optics, optical filters, and photography, a 2D temperature field can be measured non-invasively. An experiment to test the viability of using LIF-T for macroscopic thermal hydraulic experiments was developed and tested. A reference calibration curve to relate fluorescence measurements to temperature is presented. (author)

Fast-growing Acer rubrum differs from slow-growing Quercus alba in leaf, xylem and hydraulic trait coordination responses to simulated acid rain.

Science.gov (United States)

Medeiros, Juliana S; Tomeo, Nicholas J; Hewins, Charlotte R; Rosenthal, David M

2016-08-01

We investigated the effects of historic soil chemistry changes associated with acid rain, i.e., reduced soil pH and a shift from nitrogen (N)- to phosphorus (P)-limitation, on the coordination of leaf water demand and xylem hydraulic supply traits in two co-occurring temperate tree species differing in growth rate. Using a full-factorial design (N × P × pH), we measured leaf nutrient content, water relations, leaf-level and canopy-level gas exchange, total biomass and allocation, as well as stem xylem anatomy and hydraulic function for greenhouse-grown saplings of fast-growing Acer rubrum (L.) and slow-growing Quercus alba (L.). We used principle component analysis to characterize trait coordination. We found that N-limitation, but not P-limitation, had a significant impact on plant water relations and hydraulic coordination of both species. Fast-growing A. rubrum made hydraulic adjustments in response to N-limitation, but trait coordination was variable within treatments and did not fully compensate for changing allocation across N-availability. For slow-growing Q. alba, N-limitation engendered more strict coordination of leaf and xylem traits, resulting in similar leaf water content and hydraulic function across all treatments. Finally, low pH reduced the propensity of both species to adjust leaf water relations and xylem anatomical traits in response to nutrient manipulations. Our data suggest that a shift from N- to P-limitation has had a negative impact on the water relations and hydraulic function of A. rubrum to a greater extent than for Q. alba We suggest that current expansion of A. rubrum populations could be tempered by acidic N-deposition, which may restrict it to more mesic microsites. The disruption of hydraulic acclimation and coordination at low pH is emphasized as an interesting area of future study. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Two layer powder pressing

International Nuclear Information System (INIS)

Schreiner, H.

1979-01-01

First, significance and advantages of sintered materials consisting of two layers are pointed out. By means of the two layer powder pressing technique metal powders are formed resulting in compacts with high accuracy of shape and mass. Attributes of basic powders, different filling methods and pressing techniques are discussed. The described technique is supposed to find further applications in the field of two layer compacts in the near future

Efficiency of removal of bod5 and ss in sedimentation tanks and filters in wastewater treatment systems for coffee bean (Coffea arabica processing

Directory of Open Access Journals (Sweden)

Nelson Gutiérrez Guzmán

2014-12-01

Full Text Available n order to evaluate the current operating conditions of wastewater treatment systems of small scale coffee growers in the south of Huila a lab-scale prototype (S 1:25 was constructed. It was composed of both a sediment tank and a filter fit in series, simulating similar operating conditions used by coffee producers. Removal of biological oxygen demand (BOD5 and suspended solids (SS was performed in wastewater from coffee bean processing. A 23 factorial experimental design for the evaluation of the type of sedimentation tank, type of filter and hydraulic retention time (HRT in the sedimentation tank was employed. The results showed high removal efficiencies of suspended solid concentrations (more than 95%, and low removal efficiencies in BOD5 (about 20%. The combination of tank type 1 (square with a lower area, filter type 1 (upflow anaerobic filter – UAF and HRT of 30 hours had the highest removal efficiency.

Assessing the influence of the rhizosphere on soil hydraulic properties using X-ray computed tomography and numerical modelling.

Science.gov (United States)

Daly, Keith R; Mooney, Sacha J; Bennett, Malcolm J; Crout, Neil M J; Roose, Tiina; Tracy, Saoirse R

2015-04-01

Understanding the dynamics of water distribution in soil is crucial for enhancing our knowledge of managing soil and water resources. The application of X-ray computed tomography (CT) to the plant and soil sciences is now well established. However, few studies have utilized the technique for visualizing water in soil pore spaces. Here this method is utilized to visualize the water in soil in situ and in three-dimensions at successive reductive matric potentials in bulk and rhizosphere soil. The measurements are combined with numerical modelling to determine the unsaturated hydraulic conductivity, providing a complete picture of the hydraulic properties of the soil. The technique was performed on soil cores that were sampled adjacent to established roots (rhizosphere soil) and from soil that had not been influenced by roots (bulk soil). A water release curve was obtained for the different soil types using measurements of their pore geometries derived from CT imaging and verified using conventional methods, such as pressure plates. The water, soil, and air phases from the images were segmented and quantified using image analysis. The water release characteristics obtained for the contrasting soils showed clear differences in hydraulic properties between rhizosphere and bulk soil, especially in clay soil. The data suggest that soils influenced by roots (rhizosphere soil) are less porous due to increased aggregation when compared with bulk soil. The information and insights obtained on the hydraulic properties of rhizosphere and bulk soil will enhance our understanding of rhizosphere biophysics and improve current water uptake models. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Understanding, Classifying, and Selecting Environmentally Acceptable Hydraulic Fluids

Science.gov (United States)

2016-08-01

traditional mineral oil; therefore, the life cycle costs over time may be reduced . REPLACEMENT OF EXISTING HYDRAULIC FLUIDS: Hydraulic fluids in existing...properly maintaining the fluid can extend the time interval between fluid changes, thus reducing the overall operating cost of the EA hydraulic fluid. It...Environmentally Acceptable Hydraulic Fluids by Timothy J. Keyser, Robert N. Samuel, and Timothy L. Welp INTRODUCTION: On a daily basis, the United States Army

Promoting water hydraulics in Malaysia: A green educational approach

Science.gov (United States)

Yusof, Ahmad Anas; Zaili, Zarin Syukri; Hassan, Siti Nor Habibah; Tuan, Tee Boon; Saadun, Mohd Noor Asril; Ibrahim, Mohd Qadafie

2014-10-01

In promoting water hydraulics in Malaysia, this paper presents research development of water hydraulics educational training system for secondary and tertiary levels in Malaysia. Water hydraulics trainer with robotic attachment has been studied in order to promote the usefulness of such educational tools in promoting sustainability and green technology in the country. The trainer is being developed in order to allow constructive curriculum development and continuous marketing research for the effectiveness and usefulness of using water in hydraulic power trainer. The research on water-based hydraulic trainer is now possible with the current development in water hydraulics technology.

Comparative analysis of hydraulic crane-manipulating installations transport and technological machines and industrial robots hydraulic manipulators

Directory of Open Access Journals (Sweden)

Lagerev I.A.

2016-09-01

Full Text Available The article presents results of comparative analysis of hydraulic crane-manipulator installations of mobile transport and technological machines and hydraulic manipulators of industrial robots. The comparative analysis is based on consid-eration of a wide range of types and sizes indicated technical devices of both domestic and foreign production: 1580 structures of cranes and more than 450 structures of industrial robots. It was performed in the following areas: func-tional purpose and basic technical characteristics; a design; the loading conditions of the model and failures in operation process; approaches to the design, calculation methods and mathematical modeling. The conclusions about the degree of similarity and the degree of difference hydraulic crane-manipulator installations of transport and technological ma-chines and hydraulic industrial robot manipulators from the standpoint of their design and modeling occurring in them during operation of dynamic and structural processes.

Chip compacting press; Jido kirikuzu asshukuki

Energy Technology Data Exchange (ETDEWEB)

Oura, K. [Yuken Kogyo Co. Ltd., Kanagawa (Japan)

1998-08-15

The chips exhausted from various machine tools are massy, occupy much space and make working environment worse by staying added cutting oil to lower part. The chips are exhausted as a result of machining and have not constant quality. Even if used material is same the chips have various shapes and properties by kinds and machining methods of used machine tools, and are troublesome materials from a standpoint of their treatment. Pressing and solidification of the chips have frequently been tried. A chip compacting press introduced in this paper, a relatively cheap chip compacting press aimed for relatively small scale chip treatment, and has such characteristics and effects as follows. Chips are pressed and solidified by each raw material, so fractional management can be easily conducted. As casting metal chips and curled chips of iron and aluminum can be pressed to about 1/3 to 1/5 and about 1/40, respectively, space saving can be conducted. Chip compacting pressing upgrades its transporting efficiency to make possible to reduce its transporting cost. As chip solidification controls its oxidation and most cutting oil are removed, chips are easy to recycle. 2 figs., 1 tab.

Design of An Energy Efficient Hydraulic Regenerative circuit

Science.gov (United States)

Ramesh, S.; Ashok, S. Denis; Nagaraj, Shanmukha; Adithyakumar, C. R.; Reddy, M. Lohith Kumar; Naulakha, Niranjan Kumar

2018-02-01

Increasing cost and power demand, leads to evaluation of new method to increase through productivity and help to solve the power demands. Many researchers have break through to increase the efficiency of a hydraulic power pack, one of the promising methods is the concept of regenerative. The objective of this research work is to increase the efficiency of a hydraulic circuit by introducing a concept of regenerative circuit. A Regenerative circuit is a system that is used to speed up the extension stroke of the double acting single rod hydraulic cylinder. The output is connected to the input in the directional control value. By this concept, increase in velocity of the piston and decrease the cycle time. For the research, a basic hydraulic circuit and a regenerative circuit are designated and compared both with their results. The analysis was based on their time taken for extension and retraction of the piston. From the detailed analysis of both the hydraulic circuits, it is found that the efficiency by introducing hydraulic regenerative circuit increased by is 5.3%. The obtained results conclude that, implementing hydraulic regenerative circuit in a hydraulic power pack decreases power consumption, reduces cycle time and increases productivity in a longer run.

Physico-empirical approach for mapping soil hydraulic behaviour

Directory of Open Access Journals (Sweden)

G. D'Urso

1997-01-01

Full Text Available Abstract: Pedo-transfer functions are largely used in soil hydraulic characterisation of large areas. The use of physico-empirical approaches for the derivation of soil hydraulic parameters from disturbed samples data can be greatly enhanced if a characterisation performed on undisturbed cores of the same type of soil is available. In this study, an experimental procedure for deriving maps of soil hydraulic behaviour is discussed with reference to its application in an irrigation district (30 km2 in southern Italy. The main steps of the proposed procedure are: i the precise identification of soil hydraulic functions from undisturbed sampling of main horizons in representative profiles for each soil map unit; ii the determination of pore-size distribution curves from larger disturbed sampling data sets within the same soil map unit. iii the calibration of physical-empirical methods for retrieving soil hydraulic parameters from particle-size data and undisturbed soil sample analysis; iv the definition of functional hydraulic properties from water balance output; and v the delimitation of soil hydraulic map units based on functional properties.

WordPress web application development

CERN Document Server

Ratnayake, Rakhitha Nimesh

2013-01-01

An extensive, practical guide that explains how to adapt WordPress features, both conventional and trending, for web applications.This book is intended for WordPress developers and designers who have the desire to go beyond conventional website development to develop quality web applications within a limited time frame and for maximum profit. Experienced web developers who are looking for a framework for rapid application development will also find this to be a useful resource. Prior knowledge with of WordPress is preferable as the main focus will be on explaining methods for adapting WordPres

Professional WordPress Plugin Development

CERN Document Server

Williams, Brad; Tadlock, Justin

2011-01-01

Taking WordPress to the next level with advanced plugin developmentWordPress is used to create self-hosted blogs and sites, and it's fast becoming the most popular content management system (CMS) on the Web. Now you can extend it for personal, corporate and enterprise use with advanced plugins and this professional development guide. Learn how to create plugins using the WordPress plugin API: utilize hooks, store custom settings, craft translation files, secure your plugins, set custom user roles, integrate widgets, work with JavaScript and AJAX, create custom post types. You'll find a practic

WordPress 24-Hour Trainer

CERN Document Server

Plumley, George

2011-01-01

The eagerly anticipated second edition, completely updated for WordPress 3.1 As an open source content management system, WordPress allows users to easily build feature-rich web sites with no programming experience. This unique book-and-video package is a friendly, self-paced beginners guide to the latest release of WordPress. Lessons are focused on practical, everyday tasks that users will need to create and maintain their sites: entering new content, creating new pages, managing menus, making content search-engine friendly. Plus you'll find lots of tips based on years of experience teaching

Electrochemical degradation of the herbicide picloram using a filter-press flow reactor with a boron-doped diamond or β-PbO2 anode

International Nuclear Information System (INIS)

Pereira, Gabriel F.; Rocha-Filho, Romeu C.; Bocchi, Nerilso; Biaggio, Sonia R.

2015-01-01

Galvanostatic electrolyses are performed in a filter-press reactor to investigate the electrochemical degradation of picloram (100 mg L −1 , from a commercial herbicide formulation) using a boron-doped diamond (BDD) or β-PbO 2 anode. The effect of pH (3, 6, or 10), applied current density (j apl = 10, 30, or 50 mA cm −2 ), and absence or presence of Cl – ions (25 mM) in the supporting electrolyte (aqueous 0.10 M Na 2 SO 4 ) is investigated, while the picloram concentration, solution chemical oxygen demand (COD) and total organic carbon content (TOC), and energy consumption are monitored as a function of electrolysis time. From the obtained results, it is clear that the electrochemical degradation of picloram is possible using either of the anodes, but with different overall performances. In general, the presence of Cl – ions in the supporting electrolyte (leading to electrogenerated active chlorine) has a positive effect on the performance of both anodes, except for TOC abatement using the BDD anode; the best electrodegradation performances are attained at pH values around 6, when HClO is the predominant active-chlorine species. Faster rates of initial electrodegradation of picloram and of solution TOC abatement are obtained as j apl is increased, but, as expected, lower energy consumptions are always attained at the lowest value of j apl . The performances of the two anodes are virtually the same in the initial degradation of picloram; however, the BDD anode greatly surpasses the β-PbO 2 anode in the abatement of solution COD or TOC. This confirms the importance of the oxidation power of the anode, even when indirect oxidation by active chlorine plays a concomitant role.

Fundamental test results of a hydraulic free piston internal combustion engine

Energy Technology Data Exchange (ETDEWEB)

Hibi, A.; Ito, T. [Toyohashi University of Technology (Japan). Dept. of Mechanical Engineering

2004-10-01

The hydraulic free piston internal combustion engine pump that has been constructed and tested in this work is the opposed piston, two-stroke cycle, uniflow scavenging, direct fuel injection, and compression ignition type. The opposed engine pistons reciprocate the hydraulic pump pistons directly and the hydraulic power to be used in the hydraulic motors is generated. The hydraulic pressure generated is substantially constant. The opposed free pistons rest after every gas cycle and hydraulic power is continuously supplied by a hydraulic accumulator during the free pistons' rest. The smaller the hydraulic flow output, the longer the duration of the rest. Every gas cycle is performed under a fixed working condition independent of hydraulic power output. The test results in this work indicate that the number of gas cycles per second of the free piston engine pump is directly proportional to hydraulic flow output. The opposed free pistons operate every 53.2 s when hydraulic flow output is 1.02 cm{sup 3}/s; at that time hydraulic power output is 0.0124 kW. Hydraulic thermal efficiency, the ratio of hydraulic energy produced to fuel energy consumed, has been measured in the range 0.0124 kW to 4.88 kW of hydraulic power output and it has become clear that hydraulic thermal efficiency in this range is constant. The measured value of hydraulic thermal efficiency is 31 per cent. It has been demonstrated that hydraulic thermal efficiency is kept constant even if hydraulic power output is very small. (author)

Hydraulic performance numerical simulation of high specific speed mixed-flow pump based on quasi three-dimensional hydraulic design method

International Nuclear Information System (INIS)

Zhang, Y X; Su, M; Hou, H C; Song, P F

2013-01-01

This research adopts the quasi three-dimensional hydraulic design method for the impeller of high specific speed mixed-flow pump to achieve the purpose of verifying the hydraulic design method and improving hydraulic performance. Based on the two families of stream surface theory, the direct problem is completed when the meridional flow field of impeller is obtained by employing iterative calculation to settle the continuity and momentum equation of fluid. The inverse problem is completed by using the meridional flow field calculated in the direct problem. After several iterations of the direct and inverse problem, the shape of impeller and flow field information can be obtained finally when the result of iteration satisfies the convergent criteria. Subsequently the internal flow field of the designed pump are simulated by using RANS equations with RNG k-ε two-equation turbulence model. The static pressure and streamline distributions at the symmetrical cross-section, the vector velocity distribution around blades and the reflux phenomenon are analyzed. The numerical results show that the quasi three-dimensional hydraulic design method for high specific speed mixed-flow pump improves the hydraulic performance and reveal main characteristics of the internal flow of mixed-flow pump as well as provide basis for judging the rationality of the hydraulic design, improvement and optimization of hydraulic model

Analysis of the implementation of a sand bed type filter for the venting of a nuclear power plant

International Nuclear Information System (INIS)

Cuevas V, D.; Sainz M, E.; Ortiz V, J.

2017-09-01

The filtered venting of the containment has been adopted in European countries to mitigate the consequences derived from the excess pressure of the containment during a severe accident. When venting has taken place, the fission products are released directly into the environment, unless a filter is placed in the path of the same, so various types of filters are used to trap the fission products. The containment venting filters currently installed use different filtering technologies that involve more than one medium. Those who use water as the first stage of filtration are called wet systems, are equipped with additional stages to eliminate water drops and emissions of fine aerosols, and may even be equipped with an element that contains certain means of absorption for the gaseous iodine species filtration. Other designs, based on deep bed filtration as the main retention stage, called dry filters; use metal fiber, ceramic or sand filtration media to trap aerosols. The present work evaluates the hydraulic characteristics of the sand bed type filter designed by EDF as a candidate to be installed in the containment of the BWR Mark II (primary containment type of the Laguna Verde nuclear power plant). The evaluation of the sand bed filter was performed using the OpenFOAM open source software package. Models of each zone of the filtering device were generated and by means of a series of parametric calculations of computational fluid mechanics, the relevant hydrodynamic characteristics of the device were obtained, such as pressure drops against mass flow and pressure fields and velocity under different operating conditions. On the other hand, the validation of the sand bed filter model was made when comparing the results of experimental tests carried out in a sand column of the PITEAS program (1985-1986) against the simulation in OpenFOAM. The results obtained are very close to those obtained experimentally. (Author)

The Use of Filter-feeders to Manage Disease in a Changing World.

Science.gov (United States)

Burge, Colleen A; Closek, Collin J; Friedman, Carolyn S; Groner, Maya L; Jenkins, Cody M; Shore-Maggio, Amanda; Welsh, Jennifer E

2016-10-01

Rapid environmental change is linked to increases in aquatic disease heightening the need to develop strategies to manage disease. Filter-feeding species are effective biofilters and can naturally mitigate disease risk to humans and wildlife. We review the role of filter-feeders, with an emphasis on bivalves, in altering disease outcomes via augmentation and reduction. Filtration can reduce transmission by removing pathogens from the water column via degradation and release of pathogens in pseudofeces. In other cases, filtration can increase pathogen transmission and disease risk. The effect of filtration on pathogen transmission depends on the selectivity of the filter-feeder, the degree of infectivity by the pathogen, the mechanism(s) of pathogen transmission and the ability of the pathogen to resist degradation. For example, some bacteria and viruses can resist degradation and accumulate within a filter-feeder leading to disease transmission to humans and other wildlife upon ingestion. Since bivalves can concentrate microorganisms, they are also useful as sentinels for the presence of pathogenic microorganisms. While somewhat less studied, other invertebrates, including ascidians and sponges may also provide ecosystem services by altering pathogen transmission. In all scenarios, climate change may affect the potential for filter-feeders to mitigate disease risk. We conclude that an assessment including empirical data and modeling of system-wide impacts should be conducted before selection of filter-feeders to mitigate disease. Such studies should consider physiology of the host and microbe and risk factors for negative impacts including augmentation of other pathogens. © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Interplay of growth rate and xylem plasticity for optimal coordination of carbon and hydraulic economies in Fraxinus ornus trees.

Science.gov (United States)

Petit, Giai; Savi, Tadeja; Consolini, Martina; Anfodillo, Tommaso; Nardini, Andrea

2016-11-01

Efficient leaf water supply is fundamental for assimilation processes and tree growth. Renovating the architecture of the xylem transport system requires an increasing carbon investment while growing taller, and any deficiency of carbon availability may result in increasing hydraulic constraints to water flow. Therefore, plants need to coordinate carbon assimilation and biomass allocation to guarantee an efficient and safe long-distance transport system. We tested the hypothesis that reduced branch elongation rates together with carbon-saving adjustments of xylem anatomy hydraulically compensate for the reduction in biomass allocation to xylem. We measured leaf biomass, hydraulic and anatomical properties of wood segments along the main axis of branches in 10 slow growing (SG) and 10 fast growing (FG) Fraxinus ornus L. trees. Branches of SG trees had five times slower branch elongation rate (7 vs 35 cm year -1 ), and produced a higher leaf biomass (P trees in terms of leaf-specific conductivity (P > 0.05) and xylem safety (Ψ 50 ≈ -3.2 MPa). Slower elongation rate coupled with thinner annual rings and larger vessels allows the reduction of carbon costs associated with growth, while maintaining similar leaf-specific conductivity and xylem safety. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Material characterization and evaluation of Fyrquel effect on the metal part of filters in a system EHC

International Nuclear Information System (INIS)

Diaz S, A.; Zenteno S, J.; Robles P, E.; Contreras R, A.; Arganis J, C.; Griz C, M.

2014-10-01

In recent years, unexpected stoppages in power plants have been associated with problems in electro-hydraulic control systems (EHC) which generally operate with fluids to high pressure resistant to fire, but sensitive to the presence of water and contaminants that can promote damage and malfunction of government and discharge valves. The analysis here presented was performed to two filters prior to the servo valves of an EHC system that came out of service as a result of damage to these components. The study is based on analysis and inspection of metal and filter elements of these devices, integrating both chemical characterization by energy-dispersive X-ray spectroscopy of waste as materials that comprise both filters. The assessment made allowed documenting a poor design of the devices, same that promoted the stagnant fluid (Fyrquel), locally modifying the chemical composition of the medium, prompting the activation of auto-catalytic degradation processes that acidified the environment; the acid ph solutions began in susceptible sites of electrochemical corrosion processes which increased the Fyrquel contamination. (Author)

Hydraulic nuts (hydranuts) for critical bolted joints

International Nuclear Information System (INIS)

Greenwell, S.

2008-01-01

HydraNuts replace the original nut and torquing equipment, combining the two functions into one system. Designed for simple installation and operation, HydraNuts are fitted to the stud bolts. Once all HydraNuts are fitted to the application, flexible hydraulic hoses are connected, forming a closed loop hydraulic harness, allowing simultaneous pressurization of all HydraNuts. Hydraulic pressure is obtained by the use of a pumping unit and the resultant load generated is transferred to the studs and flange closure is obtained. Locking rings are rotated into place, supporting the tensioned load mechanically after hydraulic pressure is released. The hose harness is removed. (author)

A review on hydraulic fracturing of unconventional reservoir

Directory of Open Access Journals (Sweden)

Quanshu Li

2015-03-01

Full Text Available Hydraulic fracturing is widely accepted and applied to improve the gas recovery in unconventional reservoirs. Unconventional reservoirs to be addressed here are with very low permeability, complicated geological settings and in-situ stress field etc. All of these make the hydraulic fracturing process a challenging task. In order to effectively and economically recover gas from such reservoirs, the initiation and propagation of hydraulic fracturing in the heterogeneous fractured/porous media under such complicated conditions should be mastered. In this paper, some issues related to hydraulic fracturing have been reviewed, including the experimental study, field study and numerical simulation. Finally the existing problems that need to be solved on the subject of hydraulic fracturing have been proposed.

Hydraulic characterization of " Furcraea andina

Science.gov (United States)

Rivera-Velasquez, M. F.; Fallico, C.; Molinari, A.; Santillan, P.; Salazar, M.

2012-04-01

The present level of pollution, increasingly involving groundwaters, constitutes a serious risk for environment and human health. Therefore the remediation of saturated and unsaturated soils, removing pollutant materials through innovative and economic bio-remediation techniques is more frequently required. Recent studies on natural fiber development have shown the effectiveness of these fibers for removal of some heavy metals, due to the lignin content in the natural fibers which plays an important role in the adsorption of metal cations (Lee et al., 2004; Troisi et al., 2008; C. Fallico, 2010). In the context of remediation techniques for unsaturated and/or saturated zone, an experimental approach for the hydraulic characterization of the "Furcraea andina" (i.e., Cabuya Blanca) fiber was carried out. This fiber is native to Andean regions and grows easily in wild or cultivated form in the valleys and hillsides of Colombia, Ecuador, and Peru. Fibers of "Furcraea andina" were characterized by experimental tests to determine their hydraulic conductivity or permeability and porosity in order to use this medium for bioremediation of contaminated aquifer exploiting the physical, chemical and microbial capacity of natural fiber in heavy metal adsorption. To evaluate empirically the hydraulic conductivity, laboratory tests were carried out at constant head specifically on the fibers manually extracted. For these tests we used a flow cell (used as permeameter), containing the "Furcraea andina" fibers to be characterized, suitably connected by a tygon pipe to a Marriott's bottle, which had a plastic tube that allow the adjustment of the hydraulic head for different tests to a constant value. By this experiment it was also possible to identify relationships that enable the estimation of permeability as a function of density, i.e. of the compaction degree of the fibers. Our study was carried out for three values of hydraulic head (H), namely 10, 18, and 25 cm and for each

Integrating retention soil filters into urban hydrologic models - Relevant processes and important parameters

Science.gov (United States)

Bachmann-Machnik, Anna; Meyer, Daniel; Waldhoff, Axel; Fuchs, Stephan; Dittmer, Ulrich

2018-04-01

Retention Soil Filters (RSFs), a form of vertical flow constructed wetlands specifically designed for combined sewer overflow (CSO) treatment, have proven to be an effective tool to mitigate negative impacts of CSOs on receiving water bodies. Long-term hydrologic simulations are used to predict the emissions from urban drainage systems during planning of stormwater management measures. So far no universally accepted model for RSF simulation exists. When simulating hydraulics and water quality in RSFs, an appropriate level of detail must be chosen for reasonable balancing between model complexity and model handling, considering the model input's level of uncertainty. The most crucial parameters determining the resultant uncertainties of the integrated sewer system and filter bed model were identified by evaluating a virtual drainage system with a Retention Soil Filter for CSO treatment. To determine reasonable parameter ranges for RSF simulations, data of 207 events from six full-scale RSF plants in Germany were analyzed. Data evaluation shows that even though different plants with varying loading and operation modes were examined, a simple model is sufficient to assess relevant suspended solids (SS), chemical oxygen demand (COD) and NH4 emissions from RSFs. Two conceptual RSF models with different degrees of complexity were assessed. These models were developed based on evaluation of data from full scale RSF plants and column experiments. Incorporated model processes are ammonium adsorption in the filter layer and degradation during subsequent dry weather period, filtration of SS and particulate COD (XCOD) to a constant background concentration and removal of solute COD (SCOD) by a constant removal rate during filter passage as well as sedimentation of SS and XCOD in the filter overflow. XCOD, SS and ammonium loads as well as ammonium concentration peaks are discharged primarily via RSF overflow not passing through the filter bed. Uncertainties of the integrated

Experimental study of filter cake formation on different filter media

International Nuclear Information System (INIS)

Saleem, M.

2009-01-01

Removal of particulate matter from gases generated in the process industry is important for product recovery as well as emission control. Dynamics of filtration plant depend on operating conditions. The models, that predict filter plant behaviour, involve empirical resistance parameters which are usually derived from limited experimental data and are characteristics of the filter media and filter cake (dust deposited on filter medium). Filter cake characteristics are affected by the nature of filter media, process parameters and mode of filter regeneration. Removal of dust particles from air is studied in a pilot scale jet pulsed bag filter facility resembling closely to the industrial filters. Limestone dust and ambient air are used in this study with two widely different filter media. All important parameters like pressure drop, gas flow rate, dust settling, are recorded continuously at 1s interval. The data is processed for estimation of the resistance parameters. The pressure drop rise on test filter media is compared. Results reveal that the surface of filter media has an influence on pressure drop rise (concave pressure drop rise). Similar effect is produced by partially jet pulsed filter surface. Filter behaviour is also simulated using estimated parameters and a simplified model and compared with the experimental results. Distribution of cake area load is therefore an important aspect of jet pulse cleaned bag filter modeling. Mean specific cake resistance remains nearly constant on thoroughly jet pulse cleaned membrane coated filter bags. However, the trend can not be confirmed without independent cake height and density measurements. Thus the results reveal the importance of independent measurements of cake resistance. (author)

The coupled effect of fiber volume fraction and void fraction on hydraulic fluid absorption of quartz/BMI laminates

Science.gov (United States)

Hurdelbrink, Keith R.; Anderson, Jacob P.; Siddique, Zahed; Altan, M. Cengiz

2016-03-01

Bismaleimide (BMI) resin with quartz (AQ581) fiber reinforcement is a composite material frequently used in aerospace applications, such as engine cowlings and radomes. Various composite components used in aircrafts are exposed to different types of hydraulic fluids, which may lead to anomalous absorption behavior over the service life of the composite. Accurate predictive models for absorption of liquid penetrants are particularly important as the composite components are often exposed to long-term degradation due to absorbed moisture, hydraulic fluids, or similar liquid penetrants. Microstructural features such as fiber volume fraction and void fraction can have a significant effect on the absorption behavior of fiber-reinforced composites. In this paper, hydraulic fluid absorption characteristics of quartz/BMI laminates fabricated from prepregs preconditioned at different relative humidity and subsequently cured at different pressures are presented. The composite samples are immersed into hydraulic fluid at room temperature, and were not subjected to any prior degradation. To generate process-induced microvoids, prepregs were conditioned in an environmental chamber at 2% or 99% relative humidity at room temperature for a period of 24 hours prior to laminate fabrication. To alter the fiber volume fraction, the laminates were fabricated at cure pressures of 68.9 kPa (10 psi) or 482.6 kPa (70 psi) via a hot-press. The laminates are shown to have different levels of microvoids and fiber volume fractions, which were observed to affect the absorption dynamics considerably and exhibited clear non-Fickian behavior. A one-dimensional hindered diffusion model (HDM) was shown to be successful in predicting the hydraulic fluid absorption. Model prediction indicates that as the fabrication pressure increased from 68.9 kPa to 482.6 kPa, the maximum fluid content (M∞) decreased from 8.0% wt. to 1.0% wt. The degree of non-Fickian behavior, measured by hindrance coefficient (�

MST Filterability Tests

Energy Technology Data Exchange (ETDEWEB)

Poirier, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Duignan, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-03-12

The Savannah River Site (SRS) is currently treating radioactive liquid waste with the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). The low filter flux through the ARP has limited the rate at which radioactive liquid waste can be treated. Recent filter flux has averaged approximately 5 gallons per minute (gpm). Salt Batch 6 has had a lower processing rate and required frequent filter cleaning. Savannah River Remediation (SRR) has a desire to understand the causes of the low filter flux and to increase ARP/MCU throughput. In addition, at the time the testing started, SRR was assessing the impact of replacing the 0.1 micron filter with a 0.5 micron filter. This report describes testing of MST filterability to investigate the impact of filter pore size and MST particle size on filter flux and testing of filter enhancers to attempt to increase filter flux. The authors constructed a laboratory-scale crossflow filter apparatus with two crossflow filters operating in parallel. One filter was a 0.1 micron Mott sintered SS filter and the other was a 0.5 micron Mott sintered SS filter. The authors also constructed a dead-end filtration apparatus to conduct screening tests with potential filter aids and body feeds, referred to as filter enhancers. The original baseline for ARP was 5.6 M sodium salt solution with a free hydroxide concentration of approximately 1.7 M.3 ARP has been operating with a sodium concentration of approximately 6.4 M and a free hydroxide concentration of approximately 2.5 M. SRNL conducted tests varying the concentration of sodium and free hydroxide to determine whether those changes had a significant effect on filter flux. The feed slurries for the MST filterability tests were composed of simple salts (NaOH, NaNO₂, and NaNO₃) and MST (0.2 – 4.8 g/L). The feed slurry for the filter enhancer tests contained simulated salt batch 6 supernate, MST, and filter enhancers.

The Suitability of Pozzolan as Admixing Aggregate for Fe0-Based Filters

Directory of Open Access Journals (Sweden)

Arnaud Igor Ndé-Tchoupé

2018-04-01

Full Text Available Continuous gravity-fed column experiments using the methylene blue (MB discoloration method were performed to characterize the suitability of a pozzolan (PZ specimen as alternative admixing aggregate for metallic iron filters (Fe0-filters. Investigated systems were: (i pure sand, (ii pure PZ, (iii pure Fe0, (iv Fe0/sand, (v Fe0/PZ, and (vi Fe0/sand/PZ. The volumetric proportion of Fe0 was 25%. The volumetric proportions of the Fe0/sand/PZ system was 25/45/30. The initial MB concentration was 2.0 mg·L−1, 6.0 g of Fe0 was used, and the experiments lasted for 46 days. The individual systems were fed with 3.9 to 8.4 L (7.80 to 16.69 mg of MB and were characterized by the time-dependent changes of: (i the pH value, (ii the iron breakthrough, (iii the MB breakthrough, and (iv the hydraulic conductivity. Results showed that the Fe0/sand/PZ system was the most efficient. This ternary system was also the most permeable and therefore the most sustainable. The suitability of MB as a powerful operative indicator for the characterization of processes in the Fe0/H2O system was confirmed. The tested PZ is recommended as an alternative material for efficient but sustainable Fe0 filters.

Hydraulic fracturing chemicals and fluids technology

CERN Document Server

Fink, Johannes

2013-01-01

When classifying fracturing fluids and their additives, it is important that production, operation, and completion engineers understand which chemical should be utilized in different well environments. A user's guide to the many chemicals and chemical additives used in hydraulic fracturing operations, Hydraulic Fracturing Chemicals and Fluids Technology provides an easy-to-use manual to create fluid formulations that will meet project-specific needs while protecting the environment and the life of the well. Fink creates a concise and comprehensive reference that enables the engineer to logically select and use the appropriate chemicals on any hydraulic fracturing job. The first book devoted entirely to hydraulic fracturing chemicals, Fink eliminates the guesswork so the engineer can select the best chemicals needed on the job while providing the best protection for the well, workers and environment. Pinpoints the specific compounds used in any given fracturing operation Provides a systematic approach to class...

Self-potential observations during hydraulic fracturing

Energy Technology Data Exchange (ETDEWEB)

Moore, Jeffrey R.; Glaser, Steven D.

2007-09-13

The self-potential (SP) response during hydraulic fracturing of intact Sierra granite was investigated in the laboratory. Excellent correlation of pressure drop and SP suggests that the SP response is created primarily by electrokinetic coupling. For low pressures, the variation of SP with pressure drop is linear, indicating a constant coupling coefficient (Cc) of -200 mV/MPa. However for pressure drops >2 MPa, the magnitude of the Cc increases by 80% in an exponential trend. This increasing Cc is related to increasing permeability at high pore pressures caused by dilatancy of micro-cracks, and is explained by a decrease in the hydraulic tortuosity. Resistivity measurements reveal a decrease of 2% prior to hydraulic fracturing and a decrease of {approx}35% after fracturing. An asymmetric spatial SP response created by injectate diffusion into dilatant zones is observed prior to hydraulic fracturing, and in most cases this SP variation revealed the impending crack geometry seconds before failure. At rupture, injectate rushes into the new fracture area where the zeta potential is different than in the rock porosity, and an anomalous SP spike is observed. After fracturing, the spatial SP distribution reveals the direction of fracture propagation. Finally, during tensile cracking in a point load device with no water flow, a SP spike is observed that is caused by contact electrification. However, the time constant of this event is much less than that for transients observed during hydraulic fracturing, suggesting that SP created solely from material fracture does not contribute to the SP response during hydraulic fracturing.

Analysis of buffering process of control rod hydraulic absorber

International Nuclear Information System (INIS)

Bao Jishi; Qin Benke; Bo Hanliang

2011-01-01

Control Rod Hydraulic Drive Mechanism(CRHDM) is a newly invented build-in control rod drive mechanism. Hydraulic absorber is the key part of this mechanism, and is used to cushion the control rod when the rod scrams. Thus, it prevents the control rod from being deformed and damaged. In this paper dynamics program ANSYS CFX is used to calculate all kinds of flow conditions in hydraulic absorber to obtain its hydraulic characteristics. Based on the flow resistance coefficients obtained from the simulation results, fluid mass and momentum equations were developed to get the trend of pressure change in the hydraulic cylinder and the displacement of the piston rod during the buffering process of the control rod. The results obtained in this paper indicate that the hydraulic absorber meets the design requirement. The work in this paper will be helpful for the design and optimization of the control rod hydraulic absorber. (author)

Numerical study of canister filters with alternatives filter cap configurations

Science.gov (United States)

Mohammed, A. N.; Daud, A. R.; Abdullah, K.; Seri, S. M.; Razali, M. A.; Hushim, M. F.; Khalid, A.

2017-09-01

Air filtration system and filter play an important role in getting a good quality air into turbo machinery such as gas turbine. The filtration system and filter has improved the quality of air and protect the gas turbine part from contaminants which could bring damage. During separation of contaminants from the air, pressure drop cannot be avoided but it can be minimized thus helps to reduce the intake losses of the engine [1]. This study is focused on the configuration of the filter in order to obtain the minimal pressure drop along the filter. The configuration used is the basic filter geometry provided by Salutary Avenue Manufacturing Sdn Bhd. and two modified canister filter cap which is designed based on the basic filter model. The geometries of the filter are generated by using SOLIDWORKS software and Computational Fluid Dynamics (CFD) software is used to analyse and simulates the flow through the filter. In this study, the parameters of the inlet velocity are 0.032 m/s, 0.063 m/s, 0.094 m/s and 0.126 m/s. The total pressure drop produce by basic, modified filter 1 and 2 is 292.3 Pa, 251.11 Pa and 274.7 Pa. The pressure drop reduction for the modified filter 1 is 41.19 Pa and 14.1% lower compared to basic filter and the pressure drop reduction for modified filter 2 is 17.6 Pa and 6.02% lower compared to the basic filter. The pressure drops for the basic filter are slightly different with the Salutary Avenue filter due to limited data and experiment details. CFD software are very reliable in running a simulation rather than produces the prototypes and conduct the experiment thus reducing overall time and cost in this study.

Cavitation of intercellular spaces is critical to establishment of hydraulic properties of compression wood of Chamaecyparis obtusa seedlings.

Science.gov (United States)

Nakaba, Satoshi; Hirai, Asami; Kudo, Kayo; Yamagishi, Yusuke; Yamane, Kenichi; Kuroda, Katsushi; Nugroho, Widyanto Dwi; Kitin, Peter; Funada, Ryo

2016-03-01

When the orientation of the stems of conifers departs from the vertical as a result of environmental influences, conifers form compression wood that results in restoration of verticality. It is well known that intercellular spaces are formed between tracheids in compression wood, but the function of these spaces remains to be clarified. In the present study, we evaluated the impact of these spaces in artificially induced compression wood in Chamaecyparis obtusa seedlings. We monitored the presence or absence of liquid in the intercellular spaces of differentiating xylem by cryo-scanning electron microscopy. In addition, we analysed the relationship between intercellular spaces and the hydraulic properties of the compression wood. Initially, we detected small intercellular spaces with liquid in regions in which the profiles of tracheids were not rounded in transverse surfaces, indicating that the intercellular spaces had originally contained no gases. In the regions where tracheids had formed secondary walls, we found that some intercellular spaces had lost their liquid. Cavitation of intercellular spaces would affect hydraulic conductivity as a consequence of the induction of cavitation in neighbouring tracheids. Our observations suggest that cavitation of intercellular spaces is the critical event that affects not only the functions of intercellular spaces but also the hydraulic properties of compression wood. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Short-term effects of light quality on leaf gas exchange and hydraulic properties of silver birch (Betula pendula).

Science.gov (United States)

Niglas, Aigar; Papp, Kaisa; Sekiewicz, Maciej; Sellin, Arne

2017-09-01

Leaves have to acclimatize to heterogeneous radiation fields inside forest canopies in order to efficiently exploit diverse light conditions. Short-term effects of light quality on photosynthetic gas exchange, leaf water use and hydraulic traits were studied on Betula pendula Roth shoots cut from upper and lower thirds of the canopy of 39- to 35-year-old trees growing in natural forest stand, and illuminated with white, red or blue light in the laboratory. Photosynthetic machinery of the leaves developed in different spectral conditions acclimated differently with respect to incident light spectrum: the stimulating effect of complete visible spectrum (white light) on net photosynthesis is more pronounced in upper-canopy layers. Upper-canopy leaves exhibit less water saving behaviour, which may be beneficial for the fast-growing pioneer species on a daily basis. Lower-canopy leaves have lower stomatal conductance resulting in more efficient water use. Spectral gradients existing within natural forest stands represent signals for the fine-tuning of stomatal conductance and tree water relations to afford lavish water use in sun foliage and enhance leaf water-use efficiency in shade foliage sustaining greater hydraulic limitations. Higher sensitivity of hydraulic conductance of shade leaves to blue light probably contributes to the efficient use of short duration sunflecks by lower-canopy leaves. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Determination of the hydraulic residence time of trickling filters using radiotracer experiments

International Nuclear Information System (INIS)

Debien, Bruno R.; Ferreira, Ladislau M.; Barreto, Alberto A.; Pinto, Amenonia M.F.

2013-01-01

Trickling filters (TF) are bioreactors fulfilled with inert materials working as support for biofilm development, and have been used in a large scale in wastewater treatment for organic matter, ammonia nitrogen and nitrate removal. TF's can be widely used in Brazil, especially because of its simplicity and operational low cost. The efficiency of pollutants removal processes depends on the water flow dynamics inside the reactor. For this reason, in the present work the mean residence time of two TF's containing different support materials were determined by means of tracer testes. The radioisotope 82Br - a gamma radiation emitter, produced from soluble potassium bromide irradiated in the TRIGA reactor at the Centre for the Development of Nuclear Energy (CDTN) - was used as a pseudo-conservative tracer for the comparative study of aqueous phase flow dynamics in both TF's. Mean residence time for the first TF (containing a single support material) was 0,3 hours, much smaller than the value obtained for the second TF (containing two alternated support materials), around 2 hours. These results were already expected, once the alternated material is denser than the single one, and are very important for numerical modeling studies aiming to determine the kinetic constant for removal of the pollutants cited above. (author)

Determination of the hydraulic residence time of trickling filters using radiotracer experiments

Energy Technology Data Exchange (ETDEWEB)

Debien, Bruno R.; Ferreira, Ladislau M.; Barreto, Alberto A.; Pinto, Amenonia M.F., E-mail: brunordebien@gmail.com [Universidade Federal de Minas Gerais (UFMG), Minas Gerais, MG (Brazil). Dept. de Geografia. Lab. de Geomorfologia; Moreira, Rubens M., E-mail: aab@cdtn.br, E-mail: amfp@cdtn.br, E-mail: rubens@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2013-07-01

Trickling filters (TF) are bioreactors fulfilled with inert materials working as support for biofilm development, and have been used in a large scale in wastewater treatment for organic matter, ammonia nitrogen and nitrate removal. TF's can be widely used in Brazil, especially because of its simplicity and operational low cost. The efficiency of pollutants removal processes depends on the water flow dynamics inside the reactor. For this reason, in the present work the mean residence time of two TF's containing different support materials were determined by means of tracer testes. The radioisotope 82Br - a gamma radiation emitter, produced from soluble potassium bromide irradiated in the TRIGA reactor at the Centre for the Development of Nuclear Energy (CDTN) - was used as a pseudo-conservative tracer for the comparative study of aqueous phase flow dynamics in both TF's. Mean residence time for the first TF (containing a single support material) was 0,3 hours, much smaller than the value obtained for the second TF (containing two alternated support materials), around 2 hours. These results were already expected, once the alternated material is denser than the single one, and are very important for numerical modeling studies aiming to determine the kinetic constant for removal of the pollutants cited above. (author)

Drawer compacted sand filter: a new and innovative method for on-site grey water treatment.

Science.gov (United States)

Assayed, Almoayied; Chenoweth, Jonathan; Pedley, Steven

2014-01-01

In this paper, results ofa new sand filter design were presented. The drawer compacted sand filter (DCSF) is a modified design for a sand filter in which the sand layer is broken down into several layers, each of which is 10 cm high and placed in a movable drawer separated by a 10 cm space. A lab-scale DCSF was designed and operated for 330 days fed by synthetic grey water. The response of drawer sand filters to variable hydraulic and organic loading rates (HLR and OLR) in terms of biological oxygen demand (BODs), chemical oxygen demand (COD), total suspended solids (TSS), pH, electrical conductivity and Escherichia coli reductions were evaluated. The HLR was studied by increasing from 72 to 142 L m(-2) day(-1) and OLR was studied by increasing it from 23 to 30 g BOD5 m(-2) day(-1) while keeping the HLR constant at 142 L m(-2) day(-1). Each loading regime was applied for 110 days. Results showed that DCSF was able to remove >90% of organic matter and total suspended solids for all doses. No significant difference was noticed in terms of overall filter efficiency between different loads for all parameters. Significant reduction in BOD5 and COD (P water was drained through the third drawer in all tested loads. The paper concludes that DCSF would be appropriate for use in dense urban areas as its footprint is small and is appropriate for a wide range of users because of its convenience and low maintenance requirements.

Several new thermo-hydraulic test facilities in NPIC

International Nuclear Information System (INIS)

Ye Shurong; Sun Yufa; Ji Fuyun; Zong Guifang; Guo Zhongchuan

1997-01-01

Several new thermo-hydraulic test facilities are under construction in Nuclear Power Institute of Chinese (NPIC) at Chengdu. These facilities include: 1. Nuclear Power Component Comprehensive Test Facility. 2. Reactor Hydraulic Modeling Test Facility. 3. Control Rod Drive Line Hydraulic Test Facility. 4. Large Scale Thermo-Hydraulic Test Facility. The construction of these facilities will make huge progress in the research and development capability of nuclear power technology in CHINA. The author will present a brief description of the design parameters flowchart and test program of these facilities

Thermal-Hydraulic Experiments and Modelling for Advanced Nuclear Reactor Systems

International Nuclear Information System (INIS)

Song, C. H.; Baek, W. P.; Chung, M. K.

2007-06-01

The objectives of the project are to study thermal hydraulic characteristics of advanced nuclear reactor system for evaluating key thermal-hydraulic phenomena relevant to new safety concepts. To meet the research goal, several thermal hydraulic experiments were performed and related thermal hydraulic models were developed with the experimental data which were produced through the thermal hydraulic experiments. The Followings are main research topics: - Multi-dimensional Phenomena in a Reactor Vessel Downcomer - Condensation-induced Thermal Mixing in a Pool - Development of Thermal-Hydraulic Models for Two-Phase Flow - Construction of T-H Data Base

The effect of vapour pressure deficit on stomatal conductance, sap pH and leaf-specific hydraulic conductance in Eucalyptus globulus clones grown under two watering regimes.

Science.gov (United States)

Hernandez, Maria Jose; Montes, Fernando; Ruiz, Federico; Lopez, Gustavo; Pita, Pilar

2016-05-01

Stomatal conductance has long been considered of key interest in the study of plant adaptation to water stress. The expected increase in extreme meteorological events under a climate change scenario may compromise survival in Eucalyptus globulus plantations established in south-western Spain. We investigated to what extent changes in stomatal conductance in response to high vapour pressure deficits and water shortage are mediated by hydraulic and chemical signals in greenhouse-grown E. globulus clones. Rooted cuttings were grown in pots and submitted to two watering regimes. Stomatal conductance, shoot water potential, sap pH and hydraulic conductance were measured consecutively in each plant over 4 weeks under vapour pressure deficits ranging 0·42 to 2·25 kPa. Evapotranspiration, growth in leaf area and shoot biomass were also determined. There was a significant effect of both clone and watering regime in stomatal conductance and leaf-specific hydraulic conductance, but not in sap pH. Sap pH decreased as water potential and stomatal conductance decreased under increasing vapour pressure deficit. There was no significant relationship between stomatal conductance and leaf-specific hydraulic conductance. Stomata closure precluded shoot water potential from falling below -1·8 MPa. The percentage loss of hydraulic conductance ranged from 40 to 85 %. The highest and lowest leaf-specific hydraulic conductances were measured in clones from the same half-sib families. Water shortage reduced growth and evapotranspiration, decreases in evapotranspiration ranging from 14 to 32 % in the five clones tested. Changes in sap pH seemed to be a response to changes in atmospheric conditions rather than soil water in the species. Stomata closed after a considerable amount of hydraulic conductance was lost, although intraspecific differences in leaf-specific hydraulic conductance suggest the possibility of selection for improved productivity under water-limiting conditions

Pneumatic and hydraulic microactuators: a review

International Nuclear Information System (INIS)

De Volder, Michaël; Reynaerts, Dominiek

2010-01-01

The development of MEMS actuators is rapidly evolving and continuously new progress in terms of efficiency, power and force output is reported. Pneumatic and hydraulic are an interesting class of microactuators that are easily overlooked. Despite the 20 years of research, and hundreds of publications on this topic, these actuators are only popular in microfluidic systems. In other MEMS applications, pneumatic and hydraulic actuators are rare in comparison with electrostatic, thermal or piezo-electric actuators. However, several studies have shown that hydraulic and pneumatic actuators deliver among the highest force and power densities at microscale. It is believed that this asset is particularly important in modern industrial and medical microsystems, and therefore, pneumatic and hydraulic actuators could start playing an increasingly important role. This paper shows an in-depth overview of the developments in this field ranging from the classic inflatable membrane actuators to more complex piston–cylinder and drag-based microdevices. (topical review)

Indre spenninger og ytre press

DEFF Research Database (Denmark)

Ibsen, Bjarne

2011-01-01

Anmeldelse af bogen 'Norsk idrett. Indre spenninger og ytre press' redigeret af Dag Vidar Hanstad, Gunnar Breivik, Mari Kristin Sisjord og Hans B. Skaset og udgivet af forlaet akilles.......Anmeldelse af bogen 'Norsk idrett. Indre spenninger og ytre press' redigeret af Dag Vidar Hanstad, Gunnar Breivik, Mari Kristin Sisjord og Hans B. Skaset og udgivet af forlaet akilles....

FONESYS: The FOrum and NEtwork of SYStem Thermal-Hydraulic Codes in Nuclear Reactor Thermal-Hydraulics

Energy Technology Data Exchange (ETDEWEB)

Ahn, S.H., E-mail: k175ash@kins.re.kr [Korea Institute of Nuclear Safety (KINS) (Korea, Republic of); Aksan, N., E-mail: nusr.aksan@gmail.com [University of Pisa San Piero a Grado Nuclear Research Group (GRNSPG) (Italy); Austregesilo, H., E-mail: henrique.austregesilo@grs.de [Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) (Germany); Bestion, D., E-mail: dominique.bestion@cea.fr [Commissariat à l’énergie atomique et aux énergies alternatives (CEA) (France); Chung, B.D., E-mail: bdchung@kaeri.re.kr [Korea Atomic Energy Research Institute (KAERI) (Korea, Republic of); D’Auria, F., E-mail: f.dauria@ing.unipi.it [University of Pisa San Piero a Grado Nuclear Research Group (GRNSPG) (Italy); Emonot, P., E-mail: philippe.emonot@cea.fr [Commissariat à l’énergie atomique et aux énergies alternatives (CEA) (France); Gandrille, J.L., E-mail: jeanluc.gandrille@areva.com [AREVA NP (France); Hanninen, M., E-mail: markku.hanninen@vtt.fi [VTT Technical Research Centre of Finland (VTT) (Finland); Horvatović, I., E-mail: i.horvatovic@ing.unipi.it [University of Pisa San Piero a Grado Nuclear Research Group (GRNSPG) (Italy); Kim, K.D., E-mail: kdkim@kaeri.re.kr [Korea Atomic Energy Research Institute (KAERI) (Korea, Republic of); Kovtonyuk, A., E-mail: a.kovtonyuk@ing.unipi.it [University of Pisa San Piero a Grado Nuclear Research Group (GRNSPG) (Italy); Petruzzi, A., E-mail: a.petruzzi@ing.unipi.it [University of Pisa San Piero a Grado Nuclear Research Group (GRNSPG) (Italy)

2015-01-15

Highlights: • We briefly presented the project called Forum and Network of System Thermal-Hydraulics Codes in Nuclear Reactor Thermal-Hydraulics (FONESYS). • We presented FONESYS participants and their codes. • We explained FONESYS projects motivation, its main targets and working modalities. • We presented FONESYS position about projects topics and subtopics. - Abstract: The purpose of this article is to present briefly the project called Forum and Network of System Thermal-Hydraulics Codes in Nuclear Reactor Thermal-Hydraulics (FONESYS), its participants, the motivation for the project, its main targets and working modalities. System Thermal-Hydraulics (SYS-TH) codes, also as part of the Best Estimate Plus Uncertainty (BEPU) approaches, are expected to achieve a more-and-more relevant role in nuclear reactor technology, safety and design. Namely, the number of code-users can easily be predicted to increase in the countries where nuclear technology is exploited. Thus, the idea of establishing a forum and a network among the code developers and with possible extension to code users has started to have major importance and value. In this framework the FONESYS initiative has been created. The main targets of FONESYS are: • To promote the use of SYS-TH Codes and the application of the BEPU approaches. • To establish acceptable and recognized procedures and thresholds for Verification and Validation (V and V). • To create a common ground for discussing envisaged improvements in various areas, including user-interface, and the connection with other numerical tools, including Computational Fluid Dynamics (CFD) Codes.

WordPress 3 Cookbook

CERN Document Server

Shreves, Ric

2011-01-01

This is a Packt Cookbook, which means it contains step-by-step instructions to achieve a particular goal or solve a particular problem. There are plenty of screenshots and explained practical tasks to make comprehension quick and easy. This book is not specifically for developers or programmers; rather it can be used by anyone who wants to get more out of their WordPress blog by following step-by-step instructions. A basic knowledge of PHP/XHTML/CSS/WordPress is desirable but not necessary.

WordPress all-in-one for dummies

CERN Document Server

Sabin-Wilson, Lisa; Palmer, Kevin

2011-01-01

A convenient how-to guide for maximizing your WordPress experience. WordPress is a state-of-the-art blog publishing platform with nearly ten million active installations. Eight minibooks provide you with expanded coverage of the most important topics to the WordPress community, such as WordPress basics, theme designs, plug-in development, social media integration, SEO, customization, and running multiple sites. Veteran author Lisa Sabin-Wilson leads an authoritative team of authors who offer their unique knowledge and skillset while sharing invaluable advice for maximizing your site's potentia

Design of The Test Stand for Hydraulic Active Heave Compensation System

Directory of Open Access Journals (Sweden)

Jakubowski Arkadiusz

2017-01-01

Full Text Available The article presented here described the design of a test stand for hydraulic active heave compensation system. The simulation of sea waves is realized by the use of hydraulic cylinder. A hydraulic motor is used for sea waves compensation. The hydraulic cylinder and the hydraulic motor are controlled by electrohydraulic servo valves. For the measurements Authors used displacement sensor and incremental encoder. Control algorithm is implemented on the PLC. The performed tests included hydraulic actuator and hydraulic motor step responses.

Hydraulic manipulator design, analysis, and control at Oak Ridge National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Kress, R.L.; Jansen, J.F. [Oak Ridge National Lab., TN (United States). Robotics and Process Systems Div.; Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States); Basher, A.M.H. [South Carolina State Univ., Orangeburg, SC (United States)

1996-09-01

To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned to hydraulics as a means of actuation. Hydraulics have always been the actuator of choice when designing heavy-life construction and mining equipment such as bulldozers, backhoes, and tunneling devices. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem) sophisticated modeling, analysis, and control experiments are usually needed. To support the development and deployment of new hydraulic manipulators Oak Ridge National Laboratory (ORNL) has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The hydraulics laboratory at ORNL has three different manipulators. First is a 6-Degree-of-Freedom (6-DoF), multi-planer, teleoperated, flexible controls test bed used for the development of waste tank clean-up manipulator controls, thermal studies, system characterization, and manipulator tracking. Finally, is a human amplifier test bed used for the development of an entire new class of teleoperated systems. To compliment the hardware in the hydraulics laboratory, ORNL has developed a hydraulics simulation capability including a custom package to model the hydraulic systems and manipulators for performance studies and control development. This paper outlines the history of hydraulic manipulator developments at ORNL, describes the hydraulics laboratory, discusses the use of the equipment within the laboratory, and presents some of the initial results from experiments and modeling associated with these hydraulic manipulators. Included are some of the results from the development of the human amplifier/de-amplifier concepts, the characterization of the thermal sensitivity of hydraulic systems, and end-point tracking accuracy studies. Experimental and analytical

Hydraulic manipulator design, analysis, and control at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Kress, R.L.; Jansen, J.F.; Basher, A.M.H.

1996-09-01

To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned to hydraulics as a means of actuation. Hydraulics have always been the actuator of choice when designing heavy-life construction and mining equipment such as bulldozers, backhoes, and tunneling devices. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem) sophisticated modeling, analysis, and control experiments are usually needed. To support the development and deployment of new hydraulic manipulators Oak Ridge National Laboratory (ORNL) has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The hydraulics laboratory at ORNL has three different manipulators. First is a 6-Degree-of-Freedom (6-DoF), multi-planer, teleoperated, flexible controls test bed used for the development of waste tank clean-up manipulator controls, thermal studies, system characterization, and manipulator tracking. Finally, is a human amplifier test bed used for the development of an entire new class of teleoperated systems. To compliment the hardware in the hydraulics laboratory, ORNL has developed a hydraulics simulation capability including a custom package to model the hydraulic systems and manipulators for performance studies and control development. This paper outlines the history of hydraulic manipulator developments at ORNL, describes the hydraulics laboratory, discusses the use of the equipment within the laboratory, and presents some of the initial results from experiments and modeling associated with these hydraulic manipulators. Included are some of the results from the development of the human amplifier/de-amplifier concepts, the characterization of the thermal sensitivity of hydraulic systems, and end-point tracking accuracy studies. Experimental and analytical

Hydraulics national laboratory; Laboratoire national d`hydraulique

Energy Technology Data Exchange (ETDEWEB)

Chabard, J P

1996-12-31

The hydraulics national laboratory is a department of the service of applications of electric power and environment from the direction of studies and researches of Electricite de France. It has to solve the EDF problems concerning the fluids mechanics and hydraulics. Problems in PWR type reactors, fossil fuel power plants, circulating fluidized bed power plants, hydroelectric power plants relative to fluid mechanics and hydraulics studied and solved in 1995 are explained in this report. (N.C.)

A HISTORICAL PERSPECTIVE OF NUCLEAR THERMAL HYDRAULICS

Energy Technology Data Exchange (ETDEWEB)

D’Auria, F; Rohatgi, Upendra S.

2017-01-12

The nuclear thermal-hydraulics discipline was developed following the needs for nuclear power plants (NPPs) and, to a more limited extent, research reactors (RR) design and safety. As in all other fields where analytical methods are involved, nuclear thermal-hydraulics took benefit of the development of computers. Thermodynamics, rather than fluid dynamics, is at the basis of the development of nuclear thermal-hydraulics together with the experiments in complex two-phase situations, namely, geometry, high thermal density, and pressure.

Hydraulics national laboratory; Laboratoire national d`hydraulique

Energy Technology Data Exchange (ETDEWEB)

Chabard, J.P.

1995-12-31

The hydraulics national laboratory is a department of the service of applications of electric power and environment from the direction of studies and researches of Electricite de France. It has to solve the EDF problems concerning the fluids mechanics and hydraulics. Problems in PWR type reactors, fossil fuel power plants, circulating fluidized bed power plants, hydroelectric power plants relative to fluid mechanics and hydraulics studied and solved in 1995 are explained in this report. (N.C.)

Robust Prediction of Hydraulic Roughness

Science.gov (United States)

2011-03-01

Manning’s n were required as input for further hydraulic analyses with HEC - RAS . HYDROCAL was applied to compare different estimates of resistance... River Restoration Science Synthesis (NRRSS) demonstrated that, in 2007, river and stream restoration projects and funding were at an all time high...behavior makes this parameter very difficult to quan- tify repeatedly and accurately. A fundamental concept of hydraulic theory in the context of river

DCS Hydraulics Submittal, Bullock County, Alabama, USA

Data.gov (United States)

Federal Emergency Management Agency, Department of Homeland Security — Hydraulics data includes spatial datasets and data tables necessary for documenting the hydraulic procedures for computing flood elevations for a flood insurance...

DCS Hydraulics Submittal, Butler County, Alabama, USA

Data.gov (United States)

Federal Emergency Management Agency, Department of Homeland Security — Hydraulics data includes spatial datasets and data tables necessary for documenting the hydraulic procedures for computing flood elevations for a flood insurance...

DCS Hydraulics Submittal, Covington County, Alabama, USA

Data.gov (United States)

Federal Emergency Management Agency, Department of Homeland Security — Hydraulics data includes spatial datasets and data tables necessary for documenting the hydraulic procedures for computing flood elevations for a flood insurance...

Effect of hot pressing additives on the leachability of hot pressed sodium hydrous titanium oxide

International Nuclear Information System (INIS)

Valentine, T.M.; Sambell, R.A.J.

1980-01-01

Sodium hydrous titanium oxide is an ion exchange resin which can be used for immobilizing medium level waste (MLW) liquors. When hot pressed, it undergoes conversion to a ceramic. Three low melting point materials (borax, bismuth trioxide, and a mixture of PbO/CuO) were added to the (Na)HTiO and the effect that each of these had on aiding densification was assessed. Hot pressing temperature, applied pressure, and percentage addition of hot pressing aid were varied. Percentage open porosity, flexural strength, and leachability were measured. There was a linear relationship between the percentage open porosity and the logarithm of the leach rate for a constant percentage addition of each additive

Too Human versus the enthusiast press: Video game journalists as mediators of commodity value

Directory of Open Access Journals (Sweden)

Rebecca Carlson

2009-03-01

Full Text Available This article examines the role of mediators in the production of commodity value, arguing that there is a rise in a kind of immaterial labor, shaped by contemporary conditions of late capitalism, that functions explicitly as a mediating force. In this example, video game journalists are understood as actively engaged in producing and negotiating the value and meaning of video games for both producers and consumers. By specifically examining a moment of value contestation, a podcast debate between a journalist and a game developer, this article traces the mediating practices of the enthusiast gaming press and examines the way their history with and relationship to the video game industry continue to structure their ability to filter knowledge and shape desires.

Coordination of stem and leaf hydraulic conductance in southern California shrubs: a test of the hydraulic segmentation hypothesis.

Science.gov (United States)

Pivovaroff, Alexandria L; Sack, Lawren; Santiago, Louis S

2014-08-01

Coordination of water movement among plant organs is important for understanding plant water use strategies. The hydraulic segmentation hypothesis (HSH) proposes that hydraulic conductance in shorter lived, 'expendable' organs such as leaves and longer lived, more 'expensive' organs such as stems may be decoupled, with resistance in leaves acting as a bottleneck or 'safety valve'. We tested the HSH in woody species from a Mediterranean-type ecosystem by measuring leaf hydraulic conductance (Kleaf) and stem hydraulic conductivity (KS). We also investigated whether leaves function as safety valves by relating Kleaf and the hydraulic safety margin (stem water potential minus the water potential at which 50% of conductivity is lost (Ψstem-Ψ50)). We also examined related plant traits including the operating range of water potentials, wood density, leaf mass per area, and leaf area to sapwood area ratio to provide insight into whole-plant water use strategies. For hydrated shoots, Kleaf was negatively correlated with KS , supporting the HSH. Additionally, Kleaf was positively correlated with the hydraulic safety margin and negatively correlated with the leaf area to sapwood area ratio. Consistent with the HSH, our data indicate that leaves may act as control valves for species with high KS , or a low safety margin. This critical role of leaves appears to contribute importantly to plant ecological specialization in a drought-prone environment. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

Controlling flow conditions of test filters in iodine filters

International Nuclear Information System (INIS)

Holmberg, R.; Laine, J.

1979-03-01

Several different iodine filter and test filter designs and experience gained from their operation are presented. For the flow experiments, an iodine filter system equipped with flow regulating and measuring devices was built. In the experiments the influence of the packing method of the iodine sorption material and the influence of the flow regulating and measuring divices upon the flow conditions in the test filters was studied. On the basis of the experiments it has been shown that the flows through the test filters always can be adjusted to a correct value if there only is a high enough pressure difference available across the test filter ducting. As a result of the research, several different methods are presented with which the flows through the test filters in both operating and future iodine sorption system can easily be measured and adjusted to their correct values. (author)

Critical review of hydraulic modeling on atmospheric heat dissipation

International Nuclear Information System (INIS)

Onishi, Y.; Brown, S.M.

1977-01-01

Objectives of this study were: to define the useful roles of hydraulic modeling in understanding the predicting atmospheric effects of heat dissipation systems; to assess the state-of-the-art of hydraulic modeling of atmospheric phenomena; to inventory potentially useful existing hydraulic modeling facilities both in the United States and abroad; and to scope hydraulic model studies to assist the assessment of atmospheric effects of nuclear energy centers

The Rao-Blackwellized Particle Filter: A Filter Bank Implementation

Directory of Open Access Journals (Sweden)

Karlsson Rickard

2010-01-01

Full Text Available For computational efficiency, it is important to utilize model structure in particle filtering. One of the most important cases occurs when there exists a linear Gaussian substructure, which can be efficiently handled by Kalman filters. This is the standard formulation of the Rao-Blackwellized particle filter (RBPF. This contribution suggests an alternative formulation of this well-known result that facilitates reuse of standard filtering components and which is also suitable for object-oriented programming. Our RBPF formulation can be seen as a Kalman filter bank with stochastic branching and pruning.

Convergent Filter Bases

Directory of Open Access Journals (Sweden)

Coghetto Roland

2015-09-01

Full Text Available We are inspired by the work of Henri Cartan [16], Bourbaki [10] (TG. I Filtres and Claude Wagschal [34]. We define the base of filter, image filter, convergent filter bases, limit filter and the filter base of tails (fr: filtre des sections.

Electrochemical oxidation of bio-refractory dye in a simulated textile industry effluent using DSA electrodes in a filter-press type FM01-LC reactor.

Science.gov (United States)

Rodríguez, Francisca A; Mateo, María N; Aceves, Juan M; Rivero, Eligio P; González, Ignacio

2013-01-01

This work presents a study on degradation of indigo carmine dye in a filter-press type FM01-LC reactor using Sb2O5-doped Ti/IrO2-SnO2 dimensionally stable anode (DSA) electrodes. Micro- and macroelectrolysis studies were carried out using solutions of 0.8 mM indigo carmine in 0.05 M NaCl, which resemble blue denim laundry industrial wastewater. Microelectrolysis results show the behaviour of DSA electrodes in comparison with the behaviour of boron-doped diamond (BDD) electrodes. In general, dye degradation reactions are carried out indirectly through active chlorine generated on DSA, whereas in the case of BDD electrodes more oxidizing species are formed, mainly OH radicals, on the electrode surface. The well-characterized geometry, flow pattern and mass transport of the FM01-LC reactor used in macroelectrolysis experiments allowed the evaluation of the effect of hydrodynamic conditions on the chlorine-mediated degradation rate. Four values of Reynolds number (Re) (93, 371, 464 and 557) at four current densities (50, 100, 150 and 200 A/m2) were tested. The results show that the degradation rate is independent of Re at low current density (50 A/m2) but becomes dependent on the Re at high current density (200 A/m2). This behaviour shows the central role of mass transport and the reactor parameters and design. The low energy consumption (2.02 and 9.04 kWh/m3 for complete discolouration and chemical oxygen demand elimination at 50 A/m2, respectively) and the low cost of DSA electrodes compared to BDD make DSA electrodes promising for practical application in treating industrial textile effluents. In the present study, chlorinated organic compounds were not detected.

Hydraulic Conductivity of Residual Soil-Cement Mix

Science.gov (United States)

Govindasamy, P.; Taha, M. R.

2016-07-01

In Malaysia, although there are several researches on engineering properties of residual soils, however study on the hydraulic conductivity properties of metasedimentary residual soils is still lacking. Construction of containment walls like slurry wall techniques can be achieved with hydraulic conductivity of approximately 5 x 10-7cm/sec. The objectives of the study were to determine the physical properties of metasedimentary residual soils and to determine the influence of 1%, 3%, 5% and 10% of cement on hydraulic conductivity parameters. The coefficient of hydraulic conductivity of the soil naturally and soil-cement mixtures were determined by using the falling head test. According to the test, the hydraulic conductivity of the original soil was 4.16 x 10-8 m/s. The value decreases to 3.89 x 10-8 m/s, 2.78 x 10-8 m/s then 6.83 x 10-9 m/s with the addition of 1%, 3% and 5% of cement additives, respectively. During the hydration process, cement hydrates is formed followed by the increase in pH value and Ca(OH)2 which will alter the modification of pores size and distribution. When the quantity of cement increases, the pores size decrease. But, the addition of 10% cement gives an increased hydraulic conductivity value to 2.78 x 10-8 m/s. With 10%, the pore size increase might due to flocculation and agglomeration reaction. The generated hydraulic conductivity values will indirectly become a guide in the preliminary soil cement stabilization to modify the properties of the soil to become more like the properties of a soft rock.1. Introduction

Calculation of saturated hydraulic conductivity of bentonite

International Nuclear Information System (INIS)

He Jun

2006-01-01

Hydraulic conductivity test has some defects such as weak repeatability, time-consuming. Taking bentonite as dual porous media, the calculation formula of the distance, d 2 , between montmorillonite in intraparticle pores is deduced. Improved calculated method of hydraulic conductivity is obtained using d 2 and Poiseuille law. The method is valid through the comparison with results of test and other methods. The method is very convenient to calculate hydraulic conductivity of bentonite of certain montmorillonite content and void ratio. (authors)

Reactor Thermal Hydraulic Numerical Calculation And Modeling

International Nuclear Information System (INIS)

Duong Ngoc Hai; Dang The Ba

2008-01-01

In the paper the results of analysis of thermal hydraulic state models using the numerical codes such as COOLOD, EUREKA and RELAP5 for simulation of the reactor thermal hydraulic states are presented. The calculations, analyses of reactor thermal hydraulic state and safety were implemented using different codes. The received numerical results, which were compared each to other, to experiment measurement of Dalat (Vietnam) research reactor and published results, show their appropriateness and capacity for analyses of different appropriate cases. (author)

Efficiency limit factor analysis for the Francis-99 hydraulic turbine

Science.gov (United States)

Zeng, Y.; Zhang, L. X.; Guo, J. P.; Guo, Y. K.; Pan, Q. L.; Qian, J.

2017-01-01

The energy loss in hydraulic turbine is the most direct factor that affects the efficiency of the hydraulic turbine. Based on the analysis theory of inner energy loss of hydraulic turbine, combining the measurement data of the Francis-99, this paper calculates characteristic parameters of inner energy loss of the hydraulic turbine, and establishes the calculation model of the hydraulic turbine power. Taken the start-up test conditions given by Francis-99 as case, characteristics of the inner energy of the hydraulic turbine in transient and transformation law are researched. Further, analyzing mechanical friction in hydraulic turbine, we think that main ingredients of mechanical friction loss is the rotation friction loss between rotating runner and water body, and defined as the inner mechanical friction loss. The calculation method of the inner mechanical friction loss is given roughly. Our purpose is that explore and research the method and way increasing transformation efficiency of water flow by means of analysis energy losses in hydraulic turbine.

Nonlinear Control of Hydraulic Manipulator for Decommissioning Nuclear Reactor

Energy Technology Data Exchange (ETDEWEB)

Kim, Myoung-Ho; Lee, Sung-Uk; Kim, Chang-Hoi; Choi, Byung-Seon; Moon, Jei-Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

Robot technique is need to decommission nuclear reactor because of high radiation environment. Especially, Manipulator systems are useful for dismantling complex structure in a nuclear facility. In addition, Hydraulic system is applied to handle heavy duty object. Since hydraulic system can demonstrate high power. The manipulator with hydraulic power is already developed. To solve this problem, various nonlinear control method includes acceleration control. But, it is difficult because acceleration value is highly noisy. In this paper, the nonlinear control algorithm without acceleration control is studied. To verify, the hydraulic manipulator model had been developed. Furthermore, the numerical simulation is carried out. The nonlinear control without acceleration parameter method is developed for hydraulic manipulator. To verify control algorithm, the manipulator is modeled by MBD and the hydraulic servo system is also derived. In addition, the numerical simulation is also carried out. Especially, PID gain is determined though TDC algorithm. In the result of numerical simulation, tracking performance is good without acceleration control. Thus, the PID though TDC with SMC is good for hydraulic manipulator control.

Nonlinear Control of Hydraulic Manipulator for Decommissioning Nuclear Reactor

International Nuclear Information System (INIS)

Kim, Myoung-Ho; Lee, Sung-Uk; Kim, Chang-Hoi; Choi, Byung-Seon; Moon, Jei-Kwon

2016-01-01

Robot technique is need to decommission nuclear reactor because of high radiation environment. Especially, Manipulator systems are useful for dismantling complex structure in a nuclear facility. In addition, Hydraulic system is applied to handle heavy duty object. Since hydraulic system can demonstrate high power. The manipulator with hydraulic power is already developed. To solve this problem, various nonlinear control method includes acceleration control. But, it is difficult because acceleration value is highly noisy. In this paper, the nonlinear control algorithm without acceleration control is studied. To verify, the hydraulic manipulator model had been developed. Furthermore, the numerical simulation is carried out. The nonlinear control without acceleration parameter method is developed for hydraulic manipulator. To verify control algorithm, the manipulator is modeled by MBD and the hydraulic servo system is also derived. In addition, the numerical simulation is also carried out. Especially, PID gain is determined though TDC algorithm. In the result of numerical simulation, tracking performance is good without acceleration control. Thus, the PID though TDC with SMC is good for hydraulic manipulator control

Plant hydraulic diversity buffers forest ecosystem responses to drought

Science.gov (United States)

Anderegg, W.; Konings, A. G.; Trugman, A. T.; Pacala, S. W.; Yu, K.; Sulman, B. N.; Sperry, J.; Bowling, D. R.

2017-12-01

Drought impacts carbon, water, and energy cycles in forests and may pose a fundamental threat to forests in future climates. Plant hydraulic transport of water is central to tree drought responses, including curtailing of water loss and the risk of mortality during drought. The effect of biodiversity on ecosystem function has typically been examined in grasslands, yet the diversity of plant hydraulic strategies may influence forests' response to drought. In a combined analysis of eddy covariance measurements, remote-sensing data of plant water content variation, model simulations, and plant hydraulic trait data, we test the degree to which plant water stress schemes influence the carbon cycle and how hydraulic diversity within and across ecosystems affects large-scale drought responses. We find that current plant functional types are not well-suited to capture hydraulic variation and that higher hydraulic diversity buffers ecosystem variation during drought. Our results demonstrate that tree functional diversity, particularly hydraulic diversity, may be critical to simulate in plant functional types in current land surface model projections of future vegetation's response to climate extremes.

Application of DFT Filter Banks and Cosine Modulated Filter Banks in Filtering

Science.gov (United States)

Lin, Yuan-Pei; Vaidyanathan, P. P.

1994-01-01

None given. This is a proposal for a paper to be presented at APCCAS '94 in Taipei, Taiwan. (From outline): This work is organized as follows: Sec. II is devoted to the construction of the new 2m channel under-decimated DFT filter bank. Implementation and complexity of this DFT filter bank are discussed therein. IN a similar manner, the new 2m channel cosine modulated filter bank is discussed in Sec. III. Design examples are given in Sec. IV.

A low order adaptive control scheme for hydraulic servo systems

DEFF Research Database (Denmark)

Andersen, Torben Ole; Pedersen, Henrik Clemmensen; Bech, Michael Møller

2015-01-01

This paper deals with high-performance position control of hydraulics servo systems in general. The hydraulic servo system used is a two link robotic manipulator actuated by two hydraulic servo cylinders. A non-linear model of the hydraulic system and a Newton-Euler based model of the mechanical...

Pellet presses for remote fuel fabrication

International Nuclear Information System (INIS)

Densley, P.J.

1978-01-01

Two types of mechanical presses are being tested from the remote operation and remote maintenance aspects. Results will be used to recommend the type of press and design considerations required for operation in a remotely operated and maintained process line

A Study of Parallel Operation of an active Filter and passive Filters

DEFF Research Database (Denmark)

Chen, Zhe; Blaabjerg, Frede; Pedersen, John Kim

2002-01-01

This paper reports investigations of the parallel operations of a current controlled active filter and passive filters in a system with current harmonic sources. The task of reactive power and harmonic compensation is shared by the active filter and passive filters. The passive filters are used...... arrangements of the active and passive filters can operate relatively independently, also the compensation flexibility of the active filter can be fully exploited, such as one active filter for several harmonic sources.The simulation studies on various systems have been performed to evaluate the effectiveness...... of the systems. The results show that the power factor is corrected by the passive filters, harmonics are minimized by both active and passive filters and overloading of the filter system can be avoided....

Passive Power Filters

CERN Document Server

Künzi, R.

2015-06-15

Power converters require passive low-pass filters which are capable of reducing voltage ripples effectively. In contrast to signal filters, the components of power filters must carry large currents or withstand large voltages, respectively. In this paper, three different suitable filter struc tures for d.c./d.c. power converters with inductive load are introduced. The formulas needed to calculate the filter components are derived step by step and practical examples are given. The behaviour of the three discussed filters is compared by means of the examples. P ractical aspects for the realization of power filters are also discussed.

A study of pressureless microwave sintering, microwave-assisted hot press sintering and conventional hot pressing on properties of aluminium/alumina nanocomposite

Energy Technology Data Exchange (ETDEWEB)

Abedinzadeh, Reza; Safavi, Seyed Mohsen; Karimzadeh, Fathallah [Isfahan University, Isfahan (Iran, Islamic Republic of)

2016-05-15

Bulk Al/4wt-%Al{sub 2}O{sub 3} nanocomposites were prepared by consolidating nanocomposite powders using pressureless microwave sintering, microwave-assisted hot press sintering and conventional hot pressing techniques. Microstructural observations revealed that the microwave-assisted hot press sintering at different sintering temperatures of 400.deg.C and 500.deg.C resulted in more densification and smaller grain size for Al/Al{sub 2}O{sub 3} nanocomposite as compared with the conventional hot pressing. Moreover, the application of pressure in microwave sintering process led to more densification and grain growth. Mechanical properties resulting from microhardness and nanoindentation tests were also compared between three-method processed samples. It was found that the microwave-assisted hot-pressed sample exhibited higher hardness and elastic modulus in comparison with microwave-sintered and conventional hot-pressed samples. The improvement in the mechanical properties can be ascribed to lower porosity of microwave-assisted hot-pressed sample.

Control rod driving hydraulic pressure device

International Nuclear Information System (INIS)

Ishida, Kazuo.

1990-01-01

Discharged water after actuating control rod drives in a BWR type reactor is once discharged to a discharging header, then returned to a master control unit and, subsequently, discharged to a reactor by way of a cooling water header. The radioactive level in the discharging header and the master control unit is increased by the reactor water to increase the operator's exposure. In view of the above, a riser is disposed for connecting a hydraulic pressure control unit incorporating a directional control valve and the cooling water head. When a certain control rod is inserted, the pressurized driving water is supplied through a hydraulic pressure control unit to the control rod drives. The discharged water from the control rod drives is entered by way of the hydraulic pressure control unit into the cooling water header and then returned to the reactor by way of other hydraulic pressure control unit and the control rod drives. Thus, the reactor water is no more recycled to the master control unit to reduce the radioactive exposure. (N.H.)

Influence factors of sand-bentonite mixtures on hydraulic conductivity

International Nuclear Information System (INIS)

Chen Yonggui; Ye Weimin; Chen Bao; Wan Min; Wang Qiong

2008-01-01

Buffer material is a very important part of the engineering barrier for geological disposal of high-level radioactive nuclear waste. Compacted bentonite is attracting greater attention as buffer and backfill material because it offer impermeability and swelling properties, but the pure compacted bentonite strength decreases with increasing hydration and these will reduce the buffer capability. To solve this problem, sand is often used to form compacted sand-bentonite mixtures (SBMs) providing high thermal conductivity, excellent compaction capacity, long-time stability, and low engineering cost. As to SBMs, hydraulic conductivity is a important index for evaluation barrier capability. Based on the review of research results, the factors affecting the hydraulic conductivity of SBMs were put forward including bentonite content, grain size distribution, moisture content, dry density, compacting method and energy, and bentonite type. The studies show that the hydraulic conductivity of SBMs is controlled by the hydraulic conductivity of the bentonite, it also decreases as dry density and bentonite content increase, but when the bentonite content reach a critical point, the influence of increasing bentonite to decrease the hydraulic conductivity is limited. A fine and well-graded SBMs is likely to have a lower hydraulic conductivity than a coarse and poorly graded material. The internal erosion or erodibility based on the grain size distribution of the SBMs has a negative effect on the final hydraulic conductivity. The lowest hydraulic conductivity is gained when the mixtures are compacted close to optimum moisture content. Also, the mixtures compacted at moisture contents slightly above optimum values give lower hydraulic conductivity than when compacted at slightly under the optimum moisture content. Finally, discussion was brought to importance of compaction method, compacting energy, and bentonite type to the hydraulic conductivity of SBMs. (authors)

Thermal-Hydraulic Tests for Reactor Core Safety

International Nuclear Information System (INIS)

Chun, Se Young; Chung, Moon Ki; Baek, Won Pil and others

2005-04-01

The reflood experiments for single rod annulus geometry have been performed to investigate the effect of spacer grid on thermal-hydraulics under reflood conditions. The reflood experimental loop for 6x6 rod bundle with a spacer grid developed in Korea has been provided. About 8000 data points for Post-CHF heat transfer have been obtained from the experiments About 1400 CHF data points for 3x3 Water and 5x5 Freon rod bundles have been obtained. The existing evaluation methodology for core safety under return-to-power conditions has been investigated using KAERI low flow CHF database. The hydraulic tests for turbulence mixing characteristics in subchannel of 5x5 rod bundle have been carried out using advanced measurement technique, LVD and the database for various spacer grids have been provided. In order to measure the turbulence mixing characteristics in details, the hydraulic loop with a magnified 5x5 rod bundle has been prepared. The database which was constructed through a systematic thermal hydraulic tests for the reflood phenomenon, CHF, Post-CHF is surely to be useful to the industry field, the regulation body and the development of thermal-hydraulic analysis code

Effects of pressing temperature and initial microstructure on the equal channel angular pressing of Ti-6Al-4V alloy

International Nuclear Information System (INIS)

Ko, Y.G.; Lee, Y.H.; Jung, W.S.; Shin, D.H.; Lee, C.S.

2003-01-01

The effects of pressing temperature and initial microstructure on the equal channel angular (ECA) pressing of Ti-6Al-4V alloy were investigated in this study. The ECA pressing was carried out isothermally with route C at 500 C, 600 C and 700 C for two typical microstructures, i.e., the Widmanstaetten microstructure and the equiaxed microstructure. The results showed that ECA pressing at 600 C and 700 C was successful without producing any noticeable segment at the specimen surfaces, while a large amount of surface segments were produced at 500 C. After 1 pass pressing at 600 C, the equiaxed microstructure showed more uniform material flow at the surface than the Widmanstaetten microstructure. However, this microstructural influence was diminished with increase of the number of the ECA pressing. A flow-localization parameter that quantifies the flow non-uniform tendency in case of flow softening materials was used to explain the different results in each microstructure. (orig.)

Hydraulic conductivity of rock fractures

International Nuclear Information System (INIS)

Zimmerman, R.W.; Bodvarsson, G.S.

1994-10-01

Yucca Mountain, Nevada contains numerous geological units that are highly fractured. A clear understanding of the hydraulic conductivity of fractures has been identified as an important scientific problem that must be addressed during the site characterization process. The problem of the flow of a single-phase fluid through a rough-walled rock fracture is discussed within the context of rigorous fluid mechanics. The derivation of the cubic law is given as the solution to the Navier-Stokes equations for flow between smooth, parallel plates, the only fracture geometry that is amenable to exact treatment. The various geometric and kinetic conditions that are necessary in order for the Navier-Stokes equations to be replaced by the more tractable lubrication or Hele-Shaw equations are studied and quantified. Various analytical and numerical results are reviewed pertaining to the problem of relating the effective hydraulic aperture to the statistics of the aperture distribution. These studies all lead to the conclusion that the effective hydraulic aperture is always less than the mean aperture, by a factor that depends on the ratio of the mean value of the aperture to its standard deviation. The tortuosity effect caused by regions where the rock walls are in contact with each other is studied using the Hele-Shaw equations, leading to a simple correction factor that depends on the area fraction occupied by the contact regions. Finally, the predicted hydraulic apertures are compared to measured values for eight data sets from the literature for which aperture and conductivity data were available on the same fracture. It is found that reasonably accurate predictions of hydraulic conductivity can be made based solely on the first two moments of the aperture distribution function, and the proportion of contact area. 68 refs

Advanced Hydraulic Studies on Enhancing Particle Removal

DEFF Research Database (Denmark)

He, Cheng

clarifier. The inlet zone of an existing rectangular storm water clarifier was redesigned to improve the fluid flow conditions and reduce the hydraulic head loss in order to remove the lamellar plates and adapt the clarifier to the needs of high-rate clarification of storm water with flocculant addition...... excessive local head losses and helped to select structural changes to reduce such losses. The analysis of the facility showed that with respect to hydraulic operation, the facility is a complex, highly non-linear hydraulic system. Within the existing constraints, a few structural changes examined......The removal of suspended solids and attached pollutants is one of the main treatment processes in wastewater treatment. This thesis presents studies on the hydraulic conditions of various particle removal facilities for possible ways to increase their treatment capacity and performance by utilizing...

Filter-based Aerosol Measurement Experiments using Spherical Aerosol Particles under High Temperature and High Pressure

Energy Technology Data Exchange (ETDEWEB)

Lee, Jong Chan; Jung, Woo Young; Lee, Hyun Chul; Lee, Doo Young [FNC TECH., Yongin (Korea, Republic of)

2016-05-15

Optical Particle Counter (OPC) is used to provide real-time measurement of aerosol concentration and size distribution. Glass fiber membrane filter also be used to measure average mass concentration. Three tests (MTA-1, 2 and 3) have been conducted to study thermal-hydraulic effect, a filtering tendency at given SiO{sub 2} particles. Based on the experimental results, the experiment will be carried out further with a main carrier gas of steam and different aerosol size. The test results will provide representative behavior of the aerosols under various conditions. The aim of the tests, MTA 1, 2 and 3, are to be able to 1) establish the test manuals for aerosol generation, mixing, sampling and measurement system, which defines aerosol preparation, calibration, operating and evaluation method under high pressure and high temperature 2) develop commercial aerosol test modules applicable to the thermal power plant, environmental industry, automobile exhaust gas, chemical plant, HVAC system including nuclear power plant. Based on the test results, sampled aerosol particles in the filter indicate that important parameters affecting aerosol behavior aerosols are 1) system temperature to keep above a evaporation temperature of ethanol and 2) aerosol losses due to the settling by ethanol liquid droplet.

Hydraulic Hybrid Parcel Delivery Truck Deployment, Testing & Demonstration

Energy Technology Data Exchange (ETDEWEB)

Gallo, Jean-Baptiste [Calstart Incorporated, Pasadena, CA (United States)

2014-03-07

Although hydraulic hybrid systems have shown promise over the last few years, commercial deployment of these systems has primarily been limited to Class 8 refuse trucks. In 2005, the Hybrid Truck Users Forum initiated the Parcel Delivery Working Group including the largest parcel delivery fleets in North America. The goal of the working group was to evaluate and accelerate commercialization of hydraulic hybrid technology for parcel delivery vehicles. FedEx Ground, Purolator and United Parcel Service (UPS) took delivery of the world’s first commercially available hydraulic hybrid parcel delivery trucks in early 2012. The vehicle chassis includes a Parker Hannifin hydraulic hybrid drive system, integrated and assembled by Freightliner Custom Chassis Corp., with a body installed by Morgan Olson. With funding from the U.S. Department of Energy, CALSTART and its project partners assessed the performance, reliability, maintainability and fleet acceptance of three pre-production Class 6 hydraulic hybrid parcel delivery vehicles using information and data from in-use data collection and on-road testing. This document reports on the deployment of these vehicles operated by FedEx Ground, Purolator and UPS. The results presented provide a comprehensive overview of the performance of commercial hydraulic hybrid vehicles in parcel delivery applications. This project also informs fleets and manufacturers on the overall performance of hydraulic hybrid vehicles, provides insights on how the technology can be both improved and more effectively used. The key findings and recommendations of this project fall into four major categories: -Performance, -Fleet deployment, -Maintenance, -Business case. Hydraulic hybrid technology is relatively new to the market, as commercial vehicles have been introduced only in the past few years in refuse and parcel delivery applications. Successful demonstration could pave the way for additional purchases of hydraulic hybrid vehicles throughout the

DESIGN AND CONSTRUCTION OF A HYDRAULIC PISTON

OpenAIRE

Santos De la Cruz, Eulogio; Rojas Lazo, Oswaldo; Yenque Dedios, Julio; Lavado Soto, Aurelio

2014-01-01

A hydraulic system project includes the design, materials selection and construction of the hydraulic piston, hydraulic circuit and the joint with the pump and its accesories. This equiment will be driven by the force of moving fluid, whose application is in the devices of machines, tools, printing, perforation, packing and others. El proyecto de un sistema hidráulico, comprende el diseño, selección de materiales y construcción del pistón hidráulico, circuito hidráulico y el ensamble con l...

Particle Kalman Filtering: A Nonlinear Bayesian Framework for Ensemble Kalman Filters*

KAUST Repository

Hoteit, Ibrahim

2012-02-01

This paper investigates an approximation scheme of the optimal nonlinear Bayesian filter based on the Gaussian mixture representation of the state probability distribution function. The resulting filter is similar to the particle filter, but is different from it in that the standard weight-type correction in the particle filter is complemented by the Kalman-type correction with the associated covariance matrices in the Gaussian mixture. The authors show that this filter is an algorithm in between the Kalman filter and the particle filter, and therefore is referred to as the particle Kalman filter (PKF). In the PKF, the solution of a nonlinear filtering problem is expressed as the weighted average of an “ensemble of Kalman filters” operating in parallel. Running an ensemble of Kalman filters is, however, computationally prohibitive for realistic atmospheric and oceanic data assimilation problems. For this reason, the authors consider the construction of the PKF through an “ensemble” of ensemble Kalman filters (EnKFs) instead, and call the implementation the particle EnKF (PEnKF). It is shown that different types of the EnKFs can be considered as special cases of the PEnKF. Similar to the situation in the particle filter, the authors also introduce a resampling step to the PEnKF in order to reduce the risk of weights collapse and improve the performance of the filter. Numerical experiments with the strongly nonlinear Lorenz-96 model are presented and discussed.

Idealized Compression Ratio for a Screw Briquetting Press

Directory of Open Access Journals (Sweden)

Peter Biath

2012-01-01

Full Text Available This paper deals with issues in determining the ideal compression ratio for a screw briquetting press. First, the principles of operation and a basic description of the main parts of a screw briquetting press are introduced. The next section describes the pressing space by means of 3D software. The pressing space was created using a Boolean subtract function. The final section of the paper measures the partial volumes of the pressing chamber in CATIA V5 by function of measuring. The measured values are substituted into the formula for the compression ratio, and the resulting evaluations are presented in the diagram in the conclusion of this paper.

Teach yourself visually complete WordPress

CERN Document Server

Majure, Janet

2013-01-01

Take your WordPress skills to the next level with these tips, tricks, and tasks Congratulations on getting your blog up and running with WordPress! Now are you ready to take it to the next level? Teach Yourself VISUALLY Complete WordPress takes you beyond the blogging basics with expanded tips, tricks, and techniques with clear, step-by-step instructions accompanied by screen shots. This visual book shows you how to incorporate forums, use RSS, obtain and review analytics, work with tools like Google AdSense, and much more.Shows you how to use mobile tools to edit a

Design of a Novel Electro-hydraulic Drive Downhole Tractor

Science.gov (United States)

Fang, Delei; Shang, Jianzhong; Yang, Junhong; Wang, Zhuo; Wu, Wei

2018-02-01

In order to improve the traction ability and the work efficiency of downhole tractor in oil field, a novel electro-hydraulic drive downhole tractor was designed. The tractor’s supporting mechanism and moving mechanism were analyzed based on the tractor mechanical structure. Through the introduction of hydraulic system, the hydraulic drive mechanism and the implementation process were researched. Based on software, analysis of tractor hydraulic drive characteristic and movement performance were simulated, which provide theoretical basis for the development of tractor prototype.

Volatile organic compound emissions during hot-pressing of southern pine particleboard : panel size effects and trade-off between press time and temperature

Science.gov (United States)

Wenlong Wang; Douglas J. Gardner; Melissa G.D. Baumann

2002-01-01

In previous research, it was shown that decreasing either press temperature or press time generally resulted in decreased volatile organic compound (VOC) emissions during the hot-pressing of southern pine particleboard. However, because it is impossible to reduce both pressing time and temperature while maintaining panel physical and mechanical properties, this study...

Rectifier Filters

Directory of Open Access Journals (Sweden)

Y. A. Bladyko

2010-01-01

Full Text Available The paper contains definition of a smoothing factor which is suitable for any rectifier filter. The formulae of complex smoothing factors have been developed for simple and complex passive filters. The paper shows conditions for application of calculation formulae and filters. 

River channel morphology and hydraulics properties due to introduction of plant basket hydraulic structures for river channel management

Science.gov (United States)

Kałuża, Tomasz; Radecki-Pawlik, Artur; Plesiński, Karol; Walczak, Natalia; Szoszkiewicz, Krzysztof; Radecki-Pawlik, Bartosz

2016-04-01

In the present time integrated water management is directly connected with management and direct works in river channels themselves which are taking into account morphological processes in rivers and improve flow conditions. Our work focused on the hydraulic and hydrodynamic consequences upon the introduction of the concept of the improvement of the hydromorphological conditions of the Flinta River in a given reach following river channel management concept. Based on a comprehensive study of the hydromorphological state of the river, four sections were selected where restoration measures can efficiently improve river habitat conditions in the river. For each section a set of technical and biological measures were proposed and implemented in practice. One of the proposed solutions was to construct plant basket hydraulic structures (PBHS) within the river channel, which are essentially plant barriers working as sediment traps, changing river channel morphology and are in line with concepts of Water Framework Directive. These relatively small structures work as crested weirs and unquestionably change the channel morphology. Along our work we show the results of three-year long (2013-2015) systematic measurements that provided information on the morphological consequences of introducing such structures into a river channel. Our main conclusions are as follows: 1. Plant basket hydraulic structures cause changes in hydrodynamic conditions and result in sediment accumulation and the formation of river backwaters upstream and downstream the obstacle; 2. The introduced plant basket hydraulic structures cause plant debris accumulation which influences the hydrodynamic flow conditions; 3. The installation of plant basket hydraulic structures on the river bed changes flow pattern as well as flow hydrodynamic conditions causing river braiding process; 4. The erosion rate below the plant basket hydraulic structures is due to the hydraulic work conditions of the PBHS and its

HYDRAULIC SERVO CONTROL MECHANISM

Science.gov (United States)

Hussey, R.B.; Gottsche, M.J. Jr.

1963-09-17

A hydraulic servo control mechanism of compact construction and low fluid requirements is described. The mechanism consists of a main hydraulic piston, comprising the drive output, which is connected mechanically for feedback purposes to a servo control piston. A control sleeve having control slots for the system encloses the servo piston, which acts to cover or uncover the slots as a means of controlling the operation of the system. This operation permits only a small amount of fluid to regulate the operation of the mechanism, which, as a result, is compact and relatively light. This mechanism is particuiarly adaptable to the drive and control of control rods in nuclear reactors. (auth)

Advanced Performance Hydraulic Wind Energy

Science.gov (United States)

Jones, Jack A.; Bruce, Allan; Lam, Adrienne S.

2013-01-01

The Jet Propulsion Laboratory, California Institute of Technology, has developed a novel advanced hydraulic wind energy design, which has up to 23% performance improvement over conventional wind turbine and conventional hydraulic wind energy systems with 5 m/sec winds. It also has significant cost advantages with levelized costs equal to coal (after carbon tax rebate). The design is equally applicable to tidal energy systems and has passed preliminary laboratory proof-of-performance tests, as funded by the Department of Energy.

Cross-cutting european thermal-hydraulics research for innovative nuclear systems

International Nuclear Information System (INIS)

Roelofs, F.; Class, A.; Cheng, X.; Meloni, P.; Van Tichelen, K.; Boudier, P.; Prasser, M.

2010-01-01

Thermal-hydraulics is recognized as a key scientific subject in the development of different innovative nuclear reactor systems. From the thermal-hydraulic point of view, different innovative reactors are mainly characterized by their coolants (gas, water, liquid metals and molten salt). This results in different micro- and macroscopic behavior of flow and heat transfer and requires specific models and advanced analysis tools. However, many common thermal-hydraulic issues are identified among various innovative nuclear systems. In Europe, such cross-cutting thermal-hydraulic issues are the subject of the 7. framework programme THINS (Thermal-Hydraulics of Innovative Nuclear Systems) project which runs from 2010 until 2014. This paper will describe the activities in this project which address the main identified thermal hydraulics issues for innovative nuclear systems. (authors)

Retina-Inspired Filter.

Science.gov (United States)

Doutsi, Effrosyni; Fillatre, Lionel; Antonini, Marc; Gaulmin, Julien

2018-07-01

This paper introduces a novel filter, which is inspired by the human retina. The human retina consists of three different layers: the Outer Plexiform Layer (OPL), the inner plexiform layer, and the ganglionic layer. Our inspiration is the linear transform which takes place in the OPL and has been mathematically described by the neuroscientific model "virtual retina." This model is the cornerstone to derive the non-separable spatio-temporal OPL retina-inspired filter, briefly renamed retina-inspired filter, studied in this paper. This filter is connected to the dynamic behavior of the retina, which enables the retina to increase the sharpness of the visual stimulus during filtering before its transmission to the brain. We establish that this retina-inspired transform forms a group of spatio-temporal Weighted Difference of Gaussian (WDoG) filters when it is applied to a still image visible for a given time. We analyze the spatial frequency bandwidth of the retina-inspired filter with respect to time. It is shown that the WDoG spectrum varies from a lowpass filter to a bandpass filter. Therefore, while time increases, the retina-inspired filter enables to extract different kinds of information from the input image. Finally, we discuss the benefits of using the retina-inspired filter in image processing applications such as edge detection and compression.

Simultaneous Liquid Chromatographic Determination of 10 Ultra-Violet Filters in Sunscreens.

Science.gov (United States)

Wharton, Mary; Geary, Michael; O'Connor, Niamh; Curtin, Laura; Ketcher, Krystal

2015-09-01

A rapid HPLC method was developed for the simultaneous determination of 10 UV filters found in sunscreen. The following UV filters were analyzed in this method; 2-phenylbenzimidazole-5-sulfonic acid, benzophenone-3, isoamyl p-methoxycinnamate, 4-methylbenzylidene camphor, octocrylene, ethylhexyl dimethyl 4-aminobenzoic acid, ethylhexyl methoxycinnamate, butyl methoxydibenzoylmethane, ethylhexyl salicylate and homosalate. The method was developed on two columns; a Thermo Hypersil C18 BDS, 3 µm column (4.6 × 100 mm) and a Chromolith RP-18e Monolithic column (4.6 × 100 mm). The same mobile phase of ethanol and 1% acetic acid (70:30, v/v) was employed for both columns. The separation of the 10 UV filters was carried out successfully on both columns; the optimal resolution was obtained on the Thermo Scientific Hypersil column in a time frame of 7 min. An isocratic elution utilizing ethanol and acetic acid (70:30, v/v) at a temperature of 35°C was employed. The method was applied to a number of commercial samples of sunscreen and lotions and was validated according to International Conference on Harmonisation guidelines for selectivity, linearity, accuracy, precision and robustness. A comparison of the performances of both columns was also carried out. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Horizontal steam generator thermal-hydraulics

Energy Technology Data Exchange (ETDEWEB)

Ubra, O. [SKODA Praha Company, Prague (Czechoslovakia); Doubek, M. [Czech Technical Univ., Prague (Czechoslovakia)

1995-09-01

Horizontal steam generators are typical components of nuclear power plants with pressure water reactor type VVER. Thermal-hydraulic behavior of horizontal steam generators is very different from the vertical U-tube steam generator, which has been extensively studied for several years. To contribute to the understanding of the horizontal steam generator thermal-hydraulics a computer program for 3-D steady state analysis of the PGV-1000 steam generator has been developed. By means of this computer program, a detailed thermal-hydraulic and thermodynamic study of the horizontal steam generator PGV-1000 has been carried out and a set of important steam generator characteristics has been obtained. The 3-D distribution of the void fraction and 3-D level profile as functions of load and secondary side pressure have been investigated and secondary side volumes and masses as functions of load and pressure have been evaluated. Some of the interesting results of calculations are presented in the paper.

Is high-resolution inverse characterization of heterogeneous river bed hydraulic conductivities needed and possible?

Directory of Open Access Journals (Sweden)

W. Kurtz

2013-10-01

Full Text Available River–aquifer exchange fluxes influence local and regional water balances and affect groundwater and river water quality and quantity. Unfortunately, river–aquifer exchange fluxes tend to be strongly spatially variable, and it is an open research question to which degree river bed heterogeneity has to be represented in a model in order to achieve reliable estimates of river–aquifer exchange fluxes. This research question is addressed in this paper with the help of synthetic simulation experiments, which mimic the Limmat aquifer in Zurich (Switzerland, where river–aquifer exchange fluxes and groundwater management activities play an important role. The solution of the unsaturated–saturated subsurface hydrological flow problem including river–aquifer interaction is calculated for ten different synthetic realities where the strongly heterogeneous river bed hydraulic conductivities (L are perfectly known. Hydraulic head data (100 in the default scenario are sampled from the synthetic realities. In subsequent data assimilation experiments, where L is unknown now, the hydraulic head data are used as conditioning information, with the help of the ensemble Kalman filter (EnKF. For each of the ten synthetic realities, four different ensembles of L are tested in the experiments with EnKF; one ensemble estimates high-resolution L fields with different L values for each element, and the other three ensembles estimate effective L values for 5, 3 or 2 zones. The calibration of higher-resolution L fields (i.e. fully heterogeneous or 5 zones gives better results than the calibration of L for only 3 or 2 zones in terms of reproduction of states, stream–aquifer exchange fluxes and parameters. Effective L for a limited number of zones cannot always reproduce the true states and fluxes well and results in biased estimates of net exchange fluxes between aquifer and stream. Also in case only 10 head data are used for conditioning, the high

Braile vena cava filter and greenfield filter in terms of centralization.

Science.gov (United States)

de Godoy, José Maria Pereira; Menezes da Silva, Adinaldo A; Reis, Luis Fernando; Miquelin, Daniel; Torati, José Luis Simon

2013-01-01

The aim of this study was to evaluate complications experienced during implantation of the Braile Vena Cava filter (VCF) and the efficacy of the centralization mechanism of the filter. This retrospective cohort study evaluated all Braile Biomédica VCFs implanted from 2004 to 2009 in Hospital de Base Medicine School in São José do Rio Preto, Brazil. Of particular concern was the filter's symmetry during implantation and complications experienced during the procedure. All the angiographic examinations performed during the implantation of the filters were analyzed in respect to the following parameters: migration of the filter, non-opening or difficulties in the implantation and centralization of the filter. A total of 112 Braile CVFs were implanted and there were no reports of filter opening difficulties or in respect to migration. Asymmetry was observed in 1/112 (0.9%) cases. A statistically significant difference was seen on comparing historical data on decentralization of the Greenfield filter with the data of this study. The Braile Biomédico filter is an evolution of the Greenfield filter providing improved embolus capture and better implantation symmetry.

White-tailed deer are a biotic filter during community assembly, reducing species and phylogenetic diversity.

Science.gov (United States)

Begley-Miller, Danielle R; Hipp, Andrew L; Brown, Bethany H; Hahn, Marlene; Rooney, Thomas P

2014-06-09

Community assembly entails a filtering process, where species found in a local community are those that can pass through environmental (abiotic) and biotic filters and successfully compete. Previous research has demonstrated the ability of white-tailed deer (Odocoileus virginianus) to reduce species diversity and favour browse-tolerant plant communities. In this study, we expand on our previous work by investigating deer as a possible biotic filter altering local plant community assembly. We used replicated 23-year-old deer exclosures to experimentally assess the effects of deer on species diversity (H'), richness (SR), phylogenetic community structure and phylogenetic diversity in paired browsed (control) and unbrowsed (exclosed) plots. Additionally, we developed a deer-browsing susceptibility index (DBSI) to assess the vulnerability of local species to deer. Deer browsing caused a 12 % reduction in H' and 17 % reduction in SR, consistent with previous studies. Furthermore, browsing reduced phylogenetic diversity by 63 %, causing significant phylogenetic clustering. Overall, graminoids were the least vulnerable to deer browsing based on DBSI calculations. These findings demonstrate that deer are a significant driver of plant community assembly due to their role as a selective browser, or more generally, as a biotic filter. This study highlights the importance of knowledge about the plant tree of life in assessing the effects of biotic filters on plant communities. Application of such knowledge has considerable potential to advance our understanding of plant community assembly. Published by Oxford University Press on behalf of the Annals of Botany Company.

Hydrodynamic calculation of a filter washing in liquids type used in containment venting systems

International Nuclear Information System (INIS)

Reyes G, A. A.; Sainz M, E.; Ortiz V, J.

2015-09-01

From the nuclear accident of Chernobyl, the European nuclear power plants have chosen to install filters on the venting pipes of the containment, whose function is to help to mitigate the consequences of a severe accident, by controlled depressurization of the containment passively through a filtered venting of the containment system. These systems are designed to relieve the internal pressure of the containment by means of the deliberate opening of pressure relief devices, either a valve or rupture disc during a severe accident and be channeled to the filter unit. In this paper the hydraulic response of a filter system of gases washing by liquid is evaluated, due to this information is necessary to estimate the effect that has the pressure increase of the contention on the discharge capacity of the venting pipes. By simulation of computational of fluid dynamics with the programs: CAELINUX-2014 and OpenFOAM, the hydrodynamic characteristics of the Multi Venturi System for gases washing from the containment, which could be included in the general model of the venting pipe, were obtained. Representative models of the Venturi tubes of each concentric area that forming the washing system were generated; and using parametric calculations the average mass flow rate established through each venturi, depending on its size and depth in which it is located inside the tank was estimated. Also, the pressure and mass flow rate required to activate each concentric area depending on the pressure and mass load from the containment were calculated, to estimate the maximum flow that is established through the filter. Finally, the velocity profiles and the characteristic pressure at which each area operates as well as the pressure drop of local and global discharge also were calculated. (Author)

Feasibility of a two-stage biological aerated filter for depth processing of electroplating-wastewater.

Science.gov (United States)

Liu, Bo; Yan, Dongdong; Wang, Qi; Li, Song; Yang, Shaogui; Wu, Wenfei

2009-09-01

A "two-stage biological aerated filter" (T-SBAF) consisting of two columns in series was developed to treat electroplating-wastewater. Due to the low BOD/CODcr values of electroplating-wastewater, "twice start-up" was employed to reduce the time for adaptation of microorganisms, a process that takes up of 20 days. Under steady-state conditions, the removal of CODcr and NH(4)(+)-N increased first and then decreased while the hydraulic loadings increased from 0.75 to 1.5 m(3) m(-2) h(-1). The air/water ratio had the same influence on the removal of CODcr and NH(4)(+)-N when increasing from 3:1 to 6:1. When the hydraulic loadings and air/water ratio were 1.20 m(3) m(-2) h(-1) and 4:1, the optimal removal of CODcr, NH(4)(+)-N and total-nitrogen (T-N) were 90.13%, 92.51% and 55.46%, respectively. The effluent steadily reached the wastewater reuse standard. Compared to the traditional BAF, the period before backwashing of the T-SBAF could be extended to 10days, and the recovery time was considerably shortened.

WordPress web design for dummies

CERN Document Server

Sabin-Wilson, Lisa

2013-01-01

Updated, full-color guide to creating dynamic websites with WordPress 3.6 In this updated new edition, bestselling For Dummies author and WordPress expert Lisa Sabin-Wilson makes it easy for anyone with a basic knowledge of the WordPress software to create a custom site using complementary technologies such as CSS, HTML, PHP, and MySQL. You'll not only get up to speed on essential tools and technologies and further advance your own design skills, this book also gives you pages of great case studies, so you can see just how other companies and individuals are creating compelling, customized, a

Use of Hydraulic Model for Water Loss Reduction

OpenAIRE

Mindaugas Rimeika; Anželika Jurkienė

2016-01-01

Hydraulic modeling is the modern way to apply world water engineering experience in every day practice. Hydraulic model is an effective tool in order to perform analysis of water supply system, optimization of its operation, assessment of system efficiency potential, evaluation of water network development, fire flow capabilities, energy saving opportunities and water loss reduction and ect. Hydraulic model shall include all possible engineering elements and devices allocated in a real water ...

Microchip electrophoresis-single wall carbon nanotube press-transferred electrodes for fast and reliable electrochemical sensing of melatonin and its precursors.

Science.gov (United States)

Gomez, Federico José Vicente; Martín, Aída; Silva, María Fernanda; Escarpa, Alberto

2015-08-01

In the current work, single-wall carbon nanotube press-transferred electrodes (SW-PTEs) were used for detection of melatonin (MT) and its precursors tryptophan (Trp) and serotonin (5-HT) on microchip electrophoresis (ME). SW-PTEs were simply fabricated by press transferring a filtered dispersion of single-wall carbon nanotubes on a nonconductive PMMA substrate, where single-wall carbon nanotubes act as exclusive transducers. The coupling of ME-SW-PTEs allowed the fast detection of MT, Trp, and 5-HT in less than 150 s with excellent analytical features. It exhibited an impressive antifouling performance with RSD values of ≤2 and ≤4% for migration times and peak heights, respectively (n = 12). In addition, sample analysis was also investigated by analysis of 5-HT, MT, and Trp in commercial samples obtaining excellent quantitative and reproducible recoveries with values of 96.2 ± 1.8%, 101.3 ± 0.2%, and 95.6 ± 1.2% for 5-HT, MT, and Trp, respectively. The current novel application reveals the analytical power of the press-transfer technology where the fast and reliable determination of MT and its precursors were performed directly on the nanoscale carbon nanotube detectors without the help of any other electrochemical transducer. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Review of fluid and control technology of hydraulic wind turbines

Institute of Scientific and Technical Information of China (English)

Maolin CAI; Yixuan WANG; Zongxia JIAO; Yan SHI

2017-01-01

This study examines the development of the fluid and control technology of hydraulic wind turbines.The current state of hydraulic wind turbines as a new technology is described,and its basic fluid model and typical control method are expounded by comparing various study results.Finally,the advantages of hydraulic wind turbines are enumerated.Hydraulic wind turbines are expected to become the main development direction of wind turbines.

Review of fluid and control technology of hydraulic wind turbines

Science.gov (United States)

Cai, Maolin; Wang, Yixuan; Jiao, Zongxia; Shi, Yan

2017-09-01

This study examines the development of the fluid and control technology of hydraulic wind turbines. The current state of hydraulic wind turbines as a new technology is described, and its basic fluid model and typical control method are expounded by comparing various study results. Finally, the advantages of hydraulic wind turbines are enumerated. Hydraulic wind turbines are expected to become the main development direction of wind turbines.

Searching for a Free Press in Indian Country.

Science.gov (United States)

Benton, Sherrole

1994-01-01

Describes the tribally controlled media's efforts to provide a form of checks and balances against the tribal council on behalf of the tribal community. Examines the issue of freedom of the tribal press, suggesting that tribal council's control of press's operating funds may limit press freedom. (MAB)

Experimental thermal hydraulics in support of FBR

International Nuclear Information System (INIS)

Padmakumar, G.; Anand Babu, C.; Kalyanasundaram, P.; Vaidyanathan, G.

2009-01-01

The thermal hydraulic design plays a crucial role for the safe and economical deployment of Liquid Metal Cooled Fast Breeder Reactor (LMFBR). Robust experimental programmes are required in support of LMFBR thermal hydraulics design. The philosophy of testing has been to construct small scale models to understand the physical behaviour and to build larger scale models to optimize the component design. The experiments are conducted either in sodium or using a simulant like water/air. The paper gives a brief account of the various thermal hydraulic experiments carried out in support of the design of Prototype Fast Breeder Reactor (PFBR). (author)

Elevator and hydraulics; Elevator to yuatsu

Energy Technology Data Exchange (ETDEWEB)

Nakamura, I. [Hitachi, Ltd., Tokyo (Japan)

1994-07-15

A hydraulic type elevator is installed in relatively lower buildings as compared with a rope type elevator, but the ratio in the number of installation of the former elevator is increasing. This paper explains from its construction and features to especially various control systems for the riding comfort and safety. A direct push-up system with hydraulic jacks arranged beneath a car, and an indirect push-up system that has hydraulic jacks arranged on flank of a car and transmits the movement of a plunger via a rope are available. The latter system eliminates the need of large holes to embed hydraulic jacks. While the speed is controlled by controlling flow rates of high-pressure oil, the speed, position, acceleration and even time differential calculus of the acceleration must be controlled severely. The system uses two-step control for the through-speed and the landing speed. Different systems that have been realized may include compensation for temperatures in flow rate control valves, load pressures, and oil viscosity, from learning control to fuzzy control for psychological effects, or control of inverters in motors. 13 refs., 12 figs., 1 tab.

Graphic Arts: Book Three. The Press and Related Processes.

Science.gov (United States)

Farajollahi, Karim; And Others

The third of a three-volume set of instructional materials for a graphic arts course, this manual consists of nine instructional units dealing with presses and related processes. Covered in the units are basic press fundamentals, offset press systems, offset press operating procedures, offset inks and dampening chemistry, preventive maintenance…

Hydraulic elements in reduction of vibrations in mechanical systems

Science.gov (United States)

Białas, K.; Buchacz, A.

2017-08-01

This work presents non-classical method of design of mechanic systems with subsystem reducing vibrations. The purpose of this paper is also introduces synthesis of mechanic system with reducing vibrations understand as design of this type of systems. The synthesis may be applied to modify the already existing systems in order to achieve a desired result. Elements which reduce vibrations can be constructed with passive, semi-active or active components. These considerations systems have selected active items. A hallmark of active elements it is possible to change the parameters on time of these elements and their power from an external source. The implementation of active elements is very broad. These elements can be implemented through the use of components of electrical, pneumatic, hydraulic, etc. The system was consisted from mechanical and hydraulic elements. Hydraulic elements were used as subsystem reducing unwanted vibration of mechanical system. Hydraulic elements can be realized in the form of hydraulic cylinder. In the case of an active vibration reduction in the form of hydraulic cylinder it is very important to find the corresponding values of hydraulic components. The values of these elements affect the frequency of vibrations of this sub-system which is related to the effective vibration reduction [7,11].

The hydraulic conductivity of sediments: A pore size perspective

KAUST Repository

Ren, X.W.

2017-12-06

This article presents an analysis of previously published hydraulic conductivity data for a wide range of sediments. All soils exhibit a prevalent power trend between the hydraulic conductivity and void ratio. Data trends span 12 orders of magnitude in hydraulic conductivity and collapse onto a single narrow trend when the hydraulic conductivity data are plotted versus the mean pore size, estimated using void ratio and specific surface area measurements. The sensitivity of hydraulic conductivity to changes in the void ratio is higher than the theoretical value due to two concurrent phenomena: 1) percolating large pores are responsible for most of the flow, and 2) the larger pores close first during compaction. The prediction of hydraulic conductivity based on macroscale index parameters in this and similar previous studies has reached an asymptote in the range of kmeas/5≤kpredict≤5kmeas. The remaining uncertainty underscores the important role of underlying sediment characteristics such as pore size distribution, shape, and connectivity that are not measured with index properties. Furthermore, the anisotropy in hydraulic conductivity cannot be recovered from scalar parameters such as index properties. Overall, results highlight the robustness of the physics inspired data scrutiny based Hagen–Poiseuille and Kozeny-Carman analyses.

Thermal hydraulic model validation for HOR mixed core fuel management

International Nuclear Information System (INIS)

Gibcus, H.P.M.; Vries, J.W. de; Leege, P.F.A. de

1997-01-01

A thermal-hydraulic core management model has been developed for the Hoger Onderwijsreactor (HOR), a 2 MW pool-type university research reactor. The model was adopted for safety analysis purposes in the framework of HEU/LEU core conversion studies. It is applied in the thermal-hydraulic computer code SHORT (Steady-state HOR Thermal-hydraulics) which is presently in use in designing core configurations and for in-core fuel management. An elaborate measurement program was performed for establishing the core hydraulic characteristics for a variety of conditions. The hydraulic data were obtained with a dummy fuel element with special equipment allowing a.o. direct measurement of the true core flow rate. Using these data the thermal-hydraulic model was validated experimentally. The model, experimental tests, and model validation are discussed. (author)

Hydraulic Profiling of a Parallel Channel Type Reactor Core

International Nuclear Information System (INIS)

Seo, Kyong-Won; Hwang, Dae-Hyun; Lee, Chung-Chan

2006-01-01

An advanced reactor core which consisted of closed multiple parallel channels was optimized to maximize the thermal margin of the core. The closed multiple parallel channel configurations have different characteristics to the open channels of conventional PWRs. The channels, usually assemblies, are isolated hydraulically from each other and there is no cross flow between channels. The distribution of inlet flow rate between channels is a very important design parameter in the core because distribution of inlet flow is directly proportional to a margin for a certain hydraulic parameter. The thermal hydraulic parameter may be the boiling margin, maximum fuel temperature, and critical heat flux. The inlet flow distribution of the core was optimized for the boiling margins by grouping the inlet orifices by several hydraulic regions. The procedure is called a hydraulic profiling

The advantages of hydraulic packing extraction

International Nuclear Information System (INIS)

Baker, R.S.

1991-01-01

Today's competitive environment, coupled with industry's desire to improve the efficiency of plant maintenance and operations, has management continually seeking ways to save time, money, and, at nuclear plants, radiation exposure. One area where a tremendous improvement in efficiency can be realized is valve packing removal. For example, industry experience indicates that up to 70% of the time it takes to repack a valve can be spent just removing the old packing. In some case, the bonnets of small valves are removed to facilitate packing removal and prevent stem and stuffing box damage that can occur when using packing removal picks. In other cases, small valves are simply removed and discarded because it costs less to replace the valves than to remove the packing using conventional methods. Hydraulic packing extraction greatly reduces packing removal time and will not damage the stem nor stuffing box, thus eliminating the need for bonnet removal or valve replacement. This paper will review some of the more common problems associated with manual packing extraction techniques. It will explain how hydraulic packing extraction eliminates or greatly reduces the impact of each of the problem areas. A discussion will be provided of some actual industry operating experiences related to success stories using hydraulic packing extraction. The paper will also briefly describe the operating parameters associated with hydraulic packing extraction tools. Throughout the paper, actual operating experiences from the nuclear power, fossil power, petrochemical, and refinery industries will be used to support the conclusion that hydraulic packing extraction is an alternative that can save time, money, and exposure

Properties of hot pressed MgB2/Ti tapes

International Nuclear Information System (INIS)

Kovac, P.; Husek, I.; Melisek, T.; Fedor, J.; Cambel, V.; Morawski, A.; Kario, A.

2009-01-01

Hot axial and hot isostatic pressing was applied for single-core MgB 2 /Ti tapes. Differences in transport current density, n-exponents and critical current anisotropy are discussed and related to the grain connectivity influenced by pressing. The magnetic Hall probe scanning measurements allowed observing the isolated regions for axially hot pressed sample attributed to the longitudinally oriented cracks introduced by pressing. The highest current densities were measured for the tape subjected to hot isostatic pressing due to improved connectivity.

The Mediated Amplification of a Crisis: Communicating the A/H1N1 Pandemic in Press Releases and Press Coverage in Europe.

Science.gov (United States)

Rossmann, Constanze; Meyer, Lisa; Schulz, Peter J

2018-02-01

In the aftermath of the A/H1N1 pandemic, health authorities were criticized for failures in crisis communication efforts, and the media were accused of amplifying the pandemic. Considering these criticisms, A/H1N1 provides a suitable case for examining risk amplification processes that may occur in the transfer of information from press releases to print news media during a health crisis. We integrated the social amplification of risk framework with theories of news decisions (news values, framing) in an attempt to contribute to existing research both theoretically and empirically. We conducted a quantitative content analysis of press releases disseminated by health and governmental authorities, as well as the quality and tabloid press in 10 European countries between March 2009 and March 2011. Altogether 243 press releases, 1,243 quality press articles, and 834 tabloid press articles were coded. Consistent with research on news values and framing the results suggest that quality and tabloid papers alike amplified A/H1N1 risks by emphasizing conflict and damage, presenting information in a more dramatized way, and using risk-amplifying frames to a greater extent and risk-attenuating frames to a lesser extent than press releases. To some extent, the quality and tabloid press differed in how risk information was presented. While tabloid press articles seemed to follow the leading quality press with regards to content and framing of health crisis coverage, they exhibited a stronger emphasis on drama and emotion in the way they presented information. © 2017 Society for Risk Analysis.

Balanced microwave filters

CERN Document Server

Hong, Jiasheng; Medina, Francisco; Martiacuten, Ferran

2018-01-01

This book presents and discusses strategies for the design and implementation of common-mode suppressed balanced microwave filters, including, narrowband, wideband, and ultra-wideband filters This book examines differential-mode, or balanced, microwave filters by discussing several implementations of practical realizations of these passive components. Topics covered include selective mode suppression, designs based on distributed and semi-lumped approaches, multilayer technologies, defect ground structures, coupled resonators, metamaterials, interference techniques, and substrate integrated waveguides, among others. Divided into five parts, Balanced Microwave Filters begins with an introduction that presents the fundamentals of balanced lines, circuits, and networks. Part 2 covers balanced transmission lines with common-mode noise suppression, including several types of common-mode filters and the application of such filters to enhance common-mode suppression in balanced bandpass filters. Next, Part 3 exa...

OAS :: Press Releases

Science.gov (United States)

subscriptions Videos Photos Live Webcast Social Media Facebook @oasofficial Facebook Twitter @oas_official Social Media Facebook Twitter Newsletters Press and Communications Department Contact us at: +1 (202) 370 Rights Actions against Corruption C Children Civil Registry Civil Society Contact Us Culture Cyber

DSS / Press Room

Science.gov (United States)

Defense Security Service, U.S. Department of Defense Site Map | A-Z Index | Facebook | Twitter Locations Press Room Organizational Structure Careers at DSS Doing Business with DSS Frequently Asked Classification System (NCCS) National Industrial Security System (NISS) ODAA Business Management System (OBMS

Press Oil Final Release Survey

Energy Technology Data Exchange (ETDEWEB)

Whicker, Jeffrey Jay [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ruedig, Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-05-11

There are forty-eight 55 gallon barrels filled with hydraulic oil that are candidates for release and recycle. This oil needs to be characterized prior to release. Principles of sampling as provided in MARSAME/MARSSIM approaches were used as guidance for sampling.

PRESS FREEDOM IN SINGAPORE AND MALAYSIA: DEFAMATION

OpenAIRE

Georgia Kate Chapman

2015-01-01

This paper focuses on the arguments around restriction on freedom of the press in the Strong States of Singapore and Malaysia. It assesses the presence of constraints on press freedoms in democratic western countries imposed by corporation rather than state and the similar effects that these constraints may have on bias present in publicly accessible news reporting. It argues that independence of the press does not just require protection from legal and executive regulation, but also protecti...

Hydraulic Limits on Maximum Plant Transpiration

Science.gov (United States)

Manzoni, S.; Vico, G.; Katul, G. G.; Palmroth, S.; Jackson, R. B.; Porporato, A. M.

2011-12-01

Photosynthesis occurs at the expense of water losses through transpiration. As a consequence of this basic carbon-water interaction at the leaf level, plant growth and ecosystem carbon exchanges are tightly coupled to transpiration. In this contribution, the hydraulic constraints that limit transpiration rates under well-watered conditions are examined across plant functional types and climates. The potential water flow through plants is proportional to both xylem hydraulic conductivity (which depends on plant carbon economy) and the difference in water potential between the soil and the atmosphere (the driving force that pulls water from the soil). Differently from previous works, we study how this potential flux changes with the amplitude of the driving force (i.e., we focus on xylem properties and not on stomatal regulation). Xylem hydraulic conductivity decreases as the driving force increases due to cavitation of the tissues. As a result of this negative feedback, more negative leaf (and xylem) water potentials would provide a stronger driving force for water transport, while at the same time limiting xylem hydraulic conductivity due to cavitation. Here, the leaf water potential value that allows an optimum balance between driving force and xylem conductivity is quantified, thus defining the maximum transpiration rate that can be sustained by the soil-to-leaf hydraulic system. To apply the proposed framework at the global scale, a novel database of xylem conductivity and cavitation vulnerability across plant types and biomes is developed. Conductivity and water potential at 50% cavitation are shown to be complementary (in particular between angiosperms and conifers), suggesting a tradeoff between transport efficiency and hydraulic safety. Plants from warmer and drier biomes tend to achieve larger maximum transpiration than plants growing in environments with lower atmospheric water demand. The predicted maximum transpiration and the corresponding leaf water

Hydraulic Properties related to Stream Reaeration

Energy Technology Data Exchange (ETDEWEB)

Tsivoglou, E. C.; Wallace, J. R. [School of Civil Engineering, Georgia Institute of Technology, Atlanta, GA (United States)

1970-09-15

The paper reports the results of recent and current field tracer experiments designed to investigate the relationships between the reaeration capacity of a flowing stream and the stream's hydraulic properties. The purpose of the studies is to develop models for the accurate prediction of stream reaeration capacity on the basis of observation of the associated hydraulic properties. The ability of a flowing stream to absorb oxygen from the overlying atmosphere is the principal process by which the stream is able to recover its dissolved oxygen resources once they have been depleted by bacterial degradation of organic wastes. Accurate knowledge of stream reaeration capacity is therefore a necessity in determining the required degree of waste treatment, and the associated costs, in any specific case. Oxygen absorption can only occur at the air-water interface, hence reaeration is a direct function of the rate of surface water replacement due to turbulent mixing. The latter is not directly observable, and so reaeration capacity has not been observable before the quite recent development of a gaseous radiotracer technique for field measurement of reaeration. This procedure involves the simultaneous use of three tracers, namely a fluorescent dye for time of flow, tritiated water for accurate dispersion measurement, and dissolved krypton-85 for measurement of gas transfer. Field results obtained by this technique are highly reproducible. Field tracer studies of the reaeration capacities of three medium-sized streams have been conducted over a total of about fifty river miles. Associated hydraulic properties such as stream flow, cross-sectional area, depth, velocity, hydraulic gradient and dispersion have also been measured. Features such as waterfalls, rapids and pools are included, and more than eighty observations of the reaeration capacities of individual stream reaches have been made. The paper reports the observed relationships between stream reaeration capacity and

Hydraulic properties related to stream reaeration

Energy Technology Data Exchange (ETDEWEB)

Tsivoglou, E C; Wallace, J R [School of Civil Engineering, Georgia Institute of Technology, Atlanta, GA (United States)

1970-09-15

The paper reports the results of recent and current field tracer experiments designed to investigate the relationships between the reaeration capacity of a flowing stream and the stream's hydraulic properties. The purpose of the studies is to develop models for the accurate prediction of stream reaeration capacity on the basis of observation of the associated hydraulic properties. The ability of a flowing stream to absorb oxygen from the overlying atmosphere is the principal process by which the stream is able to recover its dissolved oxygen resources once they have been depleted by bacterial degradation of organic wastes. Accurate knowledge of stream reaeration capacity is therefore a necessity in determining the required degree of waste treatment, and the associated costs, in any specific case. Oxygen absorption can only occur at the air-water interface, hence reaeration is a direct function of the rate of surface water replacement due to turbulent mixing. The latter is not directly observable, and so reaeration capacity has not been observable before the quite recent development of a gaseous radiotracer technique for field measurement of reaeration. This procedure involves the simultaneous use of three tracers, namely a fluorescent dye for time of flow, tritiated water for accurate dispersion measurement, and dissolved krypton-85 for measurement of gas transfer. Field results obtained by this technique are highly reproducible. Field tracer studies of the reaeration capacities of three medium-sized streams have been conducted over a total of about fifty river miles. Associated hydraulic properties such as stream flow, cross-sectional area, depth, velocity, hydraulic gradient and dispersion have also been measured. Features such as waterfalls, rapids and pools are included, and more than eighty observations of the reaeration capacities of individual stream reaches have been made. The paper reports the observed relationships between stream reaeration capacity and

Backflushable filter insert

International Nuclear Information System (INIS)

Keith, R.C.; Vandenberg, T.; Randolph, M.C.; Lewis, T.B.; Gillis, P.J. Jr.

1988-01-01

Filter elements are mounted on a tube plate beneath an accumulator chamber whose wall is extended by skirt and flange to form a closure for the top of pressure vessel. The accumulator chamber is annular around a central pipe which serves as the outlet for filtered water passing from the filter elements. The chamber contains filtered compressed air from supply. Periodically the filtration of water is stopped and vessel is drained. Then a valve is opened, allowing the accumulated air to flow from chamber up a pipe and down pipe, pushing the filtered water from pipe back through the filter elements to clean them. The accumulator chamber is so proportioned, relative to the volume of the system communicating therewith during backflushing, that the equilibrium pressure during backflushing cannot exceed the pressure rating of the vessel. However a line monitors the pressure at the top of the vessel, and if it rises too far a bleed valve is automatically opened to depressurise the system. The chamber is intended to replace the lid of an existing vessel to convert a filter using filter aid to one using permanent filter elements. (author)

National Laboratory of Hydraulics. 1996 progress report

International Nuclear Information System (INIS)

1996-01-01

This progress report of the National Laboratory of Hydraulics (LNH) of Electricite de France (EdF) summarizes, first, the research and development studies carried out in 1996 for the development of research tools for industrial fluid mechanics and environmental hydraulics and for the development of computer tools (computer codes and softwares for fluid mechanics modeling, modeling of reactive, compressible, two-phase and turbulent flows and of complex chemical kinetics using finite elements and finite volume methods). A second parts describes the research studies performed for other services of EdF, concerning: the functioning of nuclear reactors (thermohydraulic studies of the reactor vessel and of the primary coolant circuit, gas flows following severe accidents, fluid-structure thermal coupling etc...), fossil fuel power plants, the equipment and operation of thermal power plants and hydraulic power plants, the use of electric power. A third part summarizes the river and marine hydraulic studies carried out for other companies. (J.S.)

Filter replacement lifetime prediction

Science.gov (United States)

Hamann, Hendrik F.; Klein, Levente I.; Manzer, Dennis G.; Marianno, Fernando J.

2017-10-25

Methods and systems for predicting a filter lifetime include building a filter effectiveness history based on contaminant sensor information associated with a filter; determining a rate of filter consumption with a processor based on the filter effectiveness history; and determining a remaining filter lifetime based on the determined rate of filter consumption. Methods and systems for increasing filter economy include measuring contaminants in an internal and an external environment; determining a cost of a corrosion rate increase if unfiltered external air intake is increased for cooling; determining a cost of increased air pressure to filter external air; and if the cost of filtering external air exceeds the cost of the corrosion rate increase, increasing an intake of unfiltered external air.

Anti-clogging filter system

Science.gov (United States)

Brown, Erik P.

2015-05-19

An anti-clogging filter system for filtering a fluid containing large particles and small particles includes an enclosure with at least one individual elongated tubular filter element in the enclosure. The individual elongated tubular filter element has an internal passage, a closed end, an open end, and a filtering material in or on the individual elongated tubular filter element. The fluid travels through the open end of the elongated tubular element and through the internal passage and through the filtering material. An anti-clogging element is positioned on or adjacent the individual elongated tubular filter element and provides a fluid curtain that preferentially directs the larger particulates to one area of the filter material allowing the remainder of the filter material to remain more efficient.

Hydraulics calculation in drilling simulator

Science.gov (United States)

Malyugin, Aleksey A.; Kazunin, Dmitry V.

2018-05-01

The modeling of drilling hydraulics in the simulator system is discussed. This model is based on the previously developed quasi-steady model of an incompressible fluid flow. The model simulates the operation of all parts of the hydraulic drilling system. Based on the principles of creating a common hydraulic model, a set of new elements for well hydraulics was developed. It includes elements that correspond to the in-drillstring and annular space. There are elements controlling the inflow from the reservoir into the well and simulating the lift of gas along the annulus. New elements of the hydrosystem take into account the changing geometry of the well, loss in the bit, characteristics of the fluids including viscoplasticity. There is an opportunity specify the complications, the main one of which is gas, oil and water inflow. Correct work of models in cases of complications makes it possible to work out various methods for their elimination. The coefficients of the model are adjusted on the basis of incomplete experimental data provided by operators of drilling platforms. At the end of the article the results of modeling the elimination of gas inflow by a continuous method are presented. The values displayed in the simulator (drill pipe pressure, annulus pressure, input and output flow rates) are in good agreement with the experimental data. This exercise took one hour, which is less than the time on a real rig with the same configuration of equipment and well.

Selection vector filter framework

Science.gov (United States)

Lukac, Rastislav; Plataniotis, Konstantinos N.; Smolka, Bogdan; Venetsanopoulos, Anastasios N.

2003-10-01

We provide a unified framework of nonlinear vector techniques outputting the lowest ranked vector. The proposed framework constitutes a generalized filter class for multichannel signal processing. A new class of nonlinear selection filters are based on the robust order-statistic theory and the minimization of the weighted distance function to other input samples. The proposed method can be designed to perform a variety of filtering operations including previously developed filtering techniques such as vector median, basic vector directional filter, directional distance filter, weighted vector median filters and weighted directional filters. A wide range of filtering operations is guaranteed by the filter structure with two independent weight vectors for angular and distance domains of the vector space. In order to adapt the filter parameters to varying signal and noise statistics, we provide also the generalized optimization algorithms taking the advantage of the weighted median filters and the relationship between standard median filter and vector median filter. Thus, we can deal with both statistical and deterministic aspects of the filter design process. It will be shown that the proposed method holds the required properties such as the capability of modelling the underlying system in the application at hand, the robustness with respect to errors in the model of underlying system, the availability of the training procedure and finally, the simplicity of filter representation, analysis, design and implementation. Simulation studies also indicate that the new filters are computationally attractive and have excellent performance in environments corrupted by bit errors and impulsive noise.

DCS Hydraulics Submittal, Otero County, New Mexico, USA

Data.gov (United States)

Federal Emergency Management Agency, Department of Homeland Security — Hydraulics data includes spatial datasets and data tables necessary for documenting the hydraulic procedures for computing flood elevations for a flood insurance...

Mechanics of Hydraulic Fractures

Science.gov (United States)

Detournay, Emmanuel

2016-01-01

Hydraulic fractures represent a particular class of tensile fractures that propagate in solid media under pre-existing compressive stresses as a result of internal pressurization by an injected viscous fluid. The main application of engineered hydraulic fractures is the stimulation of oil and gas wells to increase production. Several physical processes affect the propagation of these fractures, including the flow of viscous fluid, creation of solid surfaces, and leak-off of fracturing fluid. The interplay and the competition between these processes lead to multiple length scales and timescales in the system, which reveal the shifting influence of the far-field stress, viscous dissipation, fracture energy, and leak-off as the fracture propagates.

Hydraulically actuated artificial muscles

Science.gov (United States)

Meller, M. A.; Tiwari, R.; Wajcs, K. B.; Moses, C.; Reveles, I.; Garcia, E.

2012-04-01

Hydraulic Artificial Muscles (HAMs) consisting of a polymer tube constrained by a nylon mesh are presented in this paper. Despite the actuation mechanism being similar to its popular counterpart, which are pneumatically actuated (PAM), HAMs have not been studied in depth. HAMs offer the advantage of compliance, large force to weight ratio, low maintenance, and low cost over traditional hydraulic cylinders. Muscle characterization for isometric and isobaric tests are discussed and compared to PAMs. A model incorporating the effect of mesh angle and friction have also been developed. In addition, differential swelling of the muscle on actuation has also been included in the model. An application of lab fabricated HAMs for a meso-scale robotic system is also presented.

The Influence of Hydraulic Fracturing on Carbon Storage Performance

Science.gov (United States)

Fu, Pengcheng; Settgast, Randolph R.; Hao, Yue; Morris, Joseph P.; Ryerson, Frederick J.

2017-12-01

Conventional principles of the design and operation of geologic carbon storage (GCS) require injecting CO2 below the caprock fracturing pressure to ensure the integrity of the storage complex. In nonideal storage reservoirs with relatively low permeability, pressure buildup can lead to hydraulic fracturing of the reservoir and caprock. While the GCS community has generally viewed hydraulic fractures as a key risk to storage integrity, a carefully designed stimulation treatment under appropriate geologic conditions could provide improved injectivity while maintaining overall seal integrity. A vertically contained hydraulic fracture, either in the reservoir rock or extending a limited height into the caprock, provides an effective means to access reservoir volume far from the injection well. Employing a fully coupled numerical model of hydraulic fracturing, solid deformation, and matrix fluid flow, we study the enabling conditions, processes, and mechanisms of hydraulic fracturing during CO2 injection. A hydraulic fracture's pressure-limiting behavior dictates that the near-well fluid pressure is only slightly higher than the fracturing pressure of the rock and is insensitive to injection rate and mechanical properties of the formation. Although a fracture contained solely within the reservoir rock with no caprock penetration, would be an ideal scenario, poroelastic principles dictate that sustaining such a fracture could lead to continuously increasing pressure until the caprock fractures. We also investigate the propagation pattern and injection pressure responses of a hydraulic fracture propagating in a caprock subjected to heterogeneous in situ stress. The results have important implications for the use of hydraulic fracturing as a tool for managing storage performance.

Hydraulic root water uptake models: old concerns and new insights

Science.gov (United States)

Couvreur, V.; Carminati, A.; Rothfuss, Y.; Meunier, F.; Vanderborght, J.; Javaux, M.

2014-12-01

Root water uptake (RWU) affects underground water dynamics, with consequences on plant water availability and groundwater recharge. Even though hydrological and climate models are sensitive to RWU parameters, no consensus exists on the modelling of this process. Back in the 1940ies, Van Den Honert's catenary approach was the first to investigate the use of connected hydraulic resistances to describe water flow in whole plants. However concerns such as the necessary computing when architectures get complex made this approach premature. Now that computing power increased dramatically, hydraulic RWU models are gaining popularity, notably because they naturally produce observed processes like compensatory RWU and hydraulic redistribution. Yet major concerns remain. Some are more fundamental: according to hydraulic principles, plant water potential should equilibrate with soil water potential when the plant does not transpire, which is not a general observation when using current definitions of bulk or average soil water potential. Other concerns regard the validation process: water uptake distribution is not directly measurable, which makes it hard to demonstrate whether or not hydraulic models are more accurate than other models. Eventually parameterization concerns exist: root hydraulic properties are not easily measurable, and would even fluctuate on an hourly basis due to processes like aquaporin gating. While offering opportunities to validate hydraulic RWU models, newly developed observation techniques also make us realize the increasing complexity of processes involved in soil-plant hydrodynamics, such as the change of rhizosphere hydraulic properties with soil drying. Surprisingly, once implemented into hydraulic models, these processes do not necessarily translate into more complex emerging behavior at plant scale, and might justify the use of simplified representations of the soil-plant hydraulic system.

Teenagers as Victims in the Press

Science.gov (United States)

Andersson, Gunvor; Lundstrom, Tommy

2007-01-01

Research into press reporting on young people has tended to concentrate on young people as offenders. In contrast, this article focuses on press coverage of teenagers as victims. Reports in two Swedish newspapers (a morning broadsheet and an evening tabloid) were studied over a period of four months and subjected to a qualitative analysis of…

Development of hydraulic conductivity evaluation of rocks using EK (Electro Kinetic) phenomenon (Part 2). Experimental study on hydraulic conductivity evaluation by propagation velocity of EK potential

International Nuclear Information System (INIS)

Kubota, Kenji; Suzuki, Koichi

2012-01-01

Hydraulic conductivity is one of the most important engineering properties to investigate geological structure for high level radioactive waste (HLW) disposal and/or carbon dioxide (CO 2 ) geological storage. We are developing an estimation method of hydraulic conductivity by geophysical methods cost-effectively. When an elastic wave is propagated into rocks, a weak potential is generated. This is called EK (Electro Kinetic) potential, which may have a correlation with hydraulic conductivity. Hydraulic conductivity can be estimated by measuring the propagation velocity of the EK potential. We conducted laboratory measurements of propagation velocity of EK potential by using soil and rock samples. The results demonstrated that the velocity of EK potential increased as frequency increased, and the velocity increased as hydraulic conductivity of each sample increased at the same frequency condition. These tendencies corresponded to a theory of EK potential. We calculated hydraulic conductivity by comparing measured and theoretical velocity of the EK potential based on its frequency characteristics. The differences between calculated and sample hydraulic conductivity were under one order when hydraulic conductivity of the sample was from 10 -6 m/s to 10 -4 m/s. This suggests that hydraulic conductivity from 10 -6 m/s to 10 -4 m/s can be estimated by velocity of the EK potential. (author)

Effect of rock rheology on fluid leak- off during hydraulic fracturing

Science.gov (United States)

Yarushina, V. M.; Bercovici, D.; Oristaglio, M. L.

2012-04-01

In this communication, we evaluate the effect of rock rheology on fluid leak­off during hydraulic fracturing of reservoirs. Fluid leak-off in hydraulic fracturing is often nonlinear. The simple linear model developed by Carter (1957) for flow of fracturing fluid into a reservoir has three different regions in the fractured zone: a filter cake on the fracture face, formed by solid additives from the fracturing fluid; a filtrate zone affected by invasion of the fracturing fluid; and a reservoir zone with the original formation fluid. The width of each zone, as well as its permeability and pressure drop, is assumed to remain constant. Physical intuition suggests some straightforward corrections to this classical theory to take into account the pressure dependence of permeability, the compressibility or non-Newtonian rheology of fracturing fluid, and the radial (versus linear) geometry of fluid leak­off from the borehole. All of these refinements, however, still assume that the reservoir rock adjacent to the fracture face is non­deformable. Although the effect of poroelastic stress changes on leak-off is usually thought to be negligible, at the very high fluid pressures used in hydraulic fracturing, where the stresses exceed the rock strength, elastic rheology may not be the best choice. For example, calculations show that perfectly elastic rock formations do not undergo the degree of compaction typically seen in sedimentary basins. Therefore, pseudo-elastic or elastoplastic models are used to fit observed porosity profiles with depth. Starting from balance equations for mass and momentum for fluid and rock, we derive a hydraulic flow equation coupled with a porosity equation describing rock compaction. The result resembles a pressure diffusion equation with the total compressibility being a sum of fluid, rock and pore-space compressibilities. With linear elastic rheology, the bulk formation compressibility is dominated by fluid compressibility. But the possibility

Changing ventilation filters

International Nuclear Information System (INIS)

Hackney, S.

1980-01-01

A filter changing unit has a door which interlocks with the door of a filter chamber so as to prevent contamination of the outer surfaces of the doors by radioactive material collected on the filter element and a movable support which enables a filter chamber thereonto to be stored within the unit in such a way that the doors of the unit and the filter chamber can be replaced. The door pivots and interlocks with another door by means of a bolt, a seal around the periphery lip of the first door engages the periphery of the second door to seal the gap. A support pivots into a lower filter element storage position. Inspection windows and glove ports are provided. The unit is releasably connected to the filter chamber by bolts engaging in a flange provided around an opening. (author)

Influence of Drought on the Hydraulic Efficiency and the Hydraulic Safety of the Xylem - Case of a Semi-arid Conifer.

Science.gov (United States)

Gentine, P.; Guerin, M. F.; von Arx, G.; Martin-Benito, D.; Griffin, K. L.; McDowell, N.; Pockman, W.; Andreu-Hayles, L.

2017-12-01

Recent droughts in the Southwest US have resulted in extensive mortality in the pinion pine population (Pinus Edulis). An important factor for resiliency is the ability of a plant to maintain a functional continuum between soil and leaves, allowing water's motion to be sustained or resumed. During droughts, loss of functional tracheids happens through embolism, which can be partially mitigated by increasing the hydraulic safety of the xylem. However, higher hydraulic safety is usually achieved by building narrower tracheids with thicker walls, resulting in a reduction of the hydraulic efficiency of the xylem (conductivity per unit area). Reduced efficiency constrains water transport, limits photosynthesis and might delay recovery after the drought. Supporting existing research on safety-efficiency tradeoff, we test the hypothesis that under dry conditions, isohydric pinions grow xylem that favor efficiency over safety. Using a seven-year experiment with three watering treatments (drought, control, irrigated) in New Mexico, we investigate the effect of drought on the xylem anatomy of pinions' branches. We also compare the treatment effect with interannual variations in xylem structure. We measure anatomical variables - conductivities, cell wall thicknesses, hydraulic diameter, cell reinforcement and density - and preliminarily conclude that treatment has little effect on hydraulic efficiency while hydraulic safety is significantly reduced under dry conditions. Taking advantage of an extremely dry year occurrence during the experiment, we find a sharp increase in vulnerability for xylem tissues built the same year.

Optimization of hydraulic turbine governor parameters based on WPA

Science.gov (United States)

Gao, Chunyang; Yu, Xiangyang; Zhu, Yong; Feng, Baohao

2018-01-01