Optimizing the Steel Plate Storage Yard Crane Scheduling Problem Using a Two Stage Planning/Scheduling Approach

DEFF Research Database (Denmark)

Hansen, Anders Dohn; Clausen, Jens

This paper presents the Steel Plate Storage Yard Crane Scheduling Problem. The task is to generate a schedule for two gantry cranes sharing tracks. The schedule must comply with a number of constraints and at the same time be cost efficient. We propose some ideas for a two stage planning...

Corrective Action Decision Document for Corrective Action Unit 166: Storage Yards and Contaminated Materials, Nevada Test Site, Nevada with Errata Sheet

Energy Technology Data Exchange (ETDEWEB)

Grant Evenson

2007-03-01

This Corrective Action Decision Document (CADD) has been prepared for Corrective Action Unit (CAU) 166, Storage Yards and Contaminated Materials, in accordance with the Federal Facility Agreement and Consent Order (1996). The corrective action sites (CASs) are located in Areas 2, 3, 5, and 18 of the Nevada Test Site, Nevada. Corrective Action Unit 166 is comprised of the following CASs: • 02-42-01, Cond. Release Storage Yd - North • 02-42-02, Cond. Release Storage Yd - South • 02-99-10, D-38 Storage Area • 03-42-01, Conditional Release Storage Yard • 05-19-02, Contaminated Soil and Drum • 18-01-01, Aboveground Storage Tank • 18-99-03, Wax Piles/Oil Stain The purpose of this CADD is to identify and provide the rationale for the recommendation of a corrective action alternative (CAA) for the seven CASs within CAU 166. Corrective action investigation (CAI) activities were performed from July 31, 2006, through February 28, 2007, as set forth in the CAU 166 Corrective Action Investigation Plan (NNSA/NSO, 2006).

Cylinder monitoring program

Energy Technology Data Exchange (ETDEWEB)

Alderson, J.H. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

Cylinders containing depleted uranium hexafluoride (UF{sub 6}) in storage at the Department of Energy (DOE) gaseous diffusion plants, managed by Martin Marietta Energy Systems, Inc., are being evaluated to determine their expected storage life. Cylinders evaluated recently have been in storage service for 30 to 40 years. In the present environment, the remaining life for these storage cylinders is estimated to be 30 years or greater. The group of cylinders involved in recent tests will continue to be monitored on a periodic basis, and other storage cylinders will be observed as on a statistical sample population. The program has been extended to all types of large capacity UF{sub 6} cylinders.

Evaluation of coverage of enriched UF6 cylinder storage lots by existing criticality accident alarms

International Nuclear Information System (INIS)

Lee, B.L. Jr.; Dobelbower, M.C.; Woollard, J.E.; Sutherland, P.J.; Tayloe, R.W. Jr.

1995-03-01

The Portsmouth Gaseous Diffusion Plant (PORTS) is leased from the US Department of Energy (DOE) by the United States Enrichment Corporation (USEC), a government corporation formed in 1993. PORTS is in transition from regulation by DOE to regulation by the Nuclear Regulatory Commission (NRC). One regulation is 10 CFR Part 76.89, which requires that criticality alarm systems be provided for the site. PORTS originally installed criticality accident alarm systems in all building for which nuclear criticality accidents were credible. Currently, however, alarm systems are not installed in the enriched uranium hexafluoride (UF 6 ) cylinder storage lots. This report analyzes and documents the extent to which enriched UF 6 cylinder storage lots at PORTS are covered by criticality detectors and alarms currently installed in adjacent buildings. Monte Carlo calculations are performed on simplified models of the cylinder storage lots and adjacent buildings. The storage lots modelled are X-745B, X-745C, X745D, X-745E, and X-745F. The criticality detectors modelled are located in building X-343, the building X-344A/X-342A complex, and portions of building X-330 (see Figures 1 and 2). These criticality detectors are those located closest to the cylinder storage lots. Results of this analysis indicate that the existing criticality detectors currently installed at PORTS are largely ineffective in detecting neutron radiation from criticality accidents in most of the cylinder storage lots at PORTS, except sometimes along portions of their peripheries

The spatial concentration of dust emissions measured by using 3D scanning lidar in the open storage yards of steel-making company

Science.gov (United States)

Chiang, Chih-Wei; Chiang, Hong-Wei; Chou, Huann-Ming; Sun, Shu-Huang; Lee, Jiann-Shen

2017-06-01

The wind-blown dust emissions frequently occur in the open storage yards of steel-making companies. Tracking the dust source and monitoring their dispersion are rather difficult. This type of open-air storage yards poses many environmental hazards. The 3-D scanning lidar system is effective in environmental monitoring (e.g., dust) with high temporal and spatial resolution, which is lacking in traditional ground-based measurement. The objective of this paper is to make an attempt for the flux estimation of dust concentration by using lidar system. Further, we investigate the dynamical process of dust and their relationship with local air quality monitoring data. The results show that the material storage erosion by wind ( 3.6 m/s) could cause dust to elevate up to 20m height above the material storage, and produces the flux of dust around 674 mg/s. The flux of dust is proportional to the dust mass concentration (PM10) measured by commercial ambient particular monitors.

Containment and storage of uranium hexafluoride at US Department of Energy uranium enrichment plants

International Nuclear Information System (INIS)

Barlow, C.R.; Alderson, J.H.; Blue, S.C.; Boelens, R.A.; Conkel, M.E.; Dorning, R.E.; Ecklund, C.D.; Halicks, W.G.; Henson, H.M.; Newman, V.S.; Philpot, H.E.; Taylor, M.S.; Vournazos, J.P.; Pryor, W.A.; Ziehlke, K.T.

1992-07-01

Isotopically depleted UF 6 (uranium hexafluoride) accumulates at a rate five to ten times greater than the enriched product and is stored in steel vessels at the enrichment plant sites. There are approximately 55,000 large cylinders now in storage at Paducah, Kentucky; Portsmouth, Ohio; and Oak Ridge, Tennessee. Most of them contain a nominal 14 tons of depleted UF 6 . Some of these cylinders have been in the unprotected outdoor storage environment for periods approaching 40 years. Storage experience, supplemented by limited corrosion data, suggests a service life of about 70 years under optimum conditions for the 48-in. diameter, 5/16-in.-wall pressure vessels (100 psi working pressure), using a conservative industry-established 1/4-in.-wall thickness as the service limit. In the past few years, however, factors other than atmospheric corrosion have become apparent that adversely affect the serviceability of small numbers of the storage containers and that indicate the need for a managed program to ensure maintenance ofcontainment integrity for all the cylinders in storage. The program includes periodic visual inspections of cylinders and storage yards with documentation for comparison with other inspections, a group of corrosion test programs to permit cylinder life forecasts, and identification of (and scheduling for remedial action) situations in which defects, due to handling damage or accelerated corrosion, can seriously shorten the storage life or compromise the containment integrity of individual cylinders. The program also includes rupture testing to assess the effects of certain classes of damage on overall cylinder strength, aswell as ongoing reviews of specifications, procedures, practices, and inspection results to effect improvements in handling safety, containment integrity, and storage life

Criticality Safety Evaluation for 30B and 48X UF6 Cylinders for Transportation and Storage

International Nuclear Information System (INIS)

Mokhatri, Homami Zahra; Nematollahi, Mohammadreza; Kamyab, Shahabeddin

2011-01-01

30B and 48X cylinders are two standard containers have been used for transportation and storage of uranium hexafluoride with 21/2-ton and 10-ton loading capacity, respectively. For the sake of nuclear safety, the long-term safe storage and transportation of the cylinders are necessary to be concerned. Safe limits in handling and storage of 30B and 48X cylinders from the criticality safety considerations, has been investigated in this paper, by using the MCNP.4C code with ENDF/B-VI library data for the neutron cross sections. An infinite array model (with and without over pack) incorporating an internal H/U ratio of 0.088 was then developed to determine the optimal interstitial moderation. The maximum k eff value for the conditions of optimal interstitial moderation with the premise of no water leakage into the UF 6 cylinder has been shown to be 0.79209 ± 0.0011 for the 30B cylinder and 0.7625±0.0013 for 48X cylinder with 5 wt % 235 U enrichment. Based on this evaluation, the 30B and 48X UF 6 cylinders with 5 wt % 235 U enrichment meet the 10 CFR part 71 criteria for Fissile Class I packages, even in the worst case, and has a Transport Index (TI) of zero for criticality safety purposes

Prediction of External Corrosion for Steel Cylinders--2004 Report

International Nuclear Information System (INIS)

Schmoyer, RLS

2004-01-01

Depleted uranium hexafluoride (UF 6 ) is stored in over 60,000 steel cylinders at the East Tennessee Technology Park (ETTP) in Oak Ridge, Tennessee, at the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and at the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The cylinders range in age from 4 to 53 years. Although when new the cylinders had wall thicknesses specified to within manufacturing tolerances, over the years corrosion has reduced their actual wall thicknesses. The UF 6 Cylinder Project is managed by the United States Department of Energy (DOE) to safely maintain the UF 6 and the cylinders containing it. This report documents activities that address UF 6 Cylinder Project requirements and actions involving forecasting cylinder wall thicknesses. These requirements are delineated in the System Requirements Document (LMES 1997a), and the actions needed to fulfill them are specified in the System Engineering Management Plan (LMES 1997b). The report documents cylinder wall thickness projections based on models fit to ultrasonic thickness (UT) measurement data. UT data is collected at various locations on randomly sampled cylinders. For each cylinder sampled, the minimum UT measurement approximates the actual minimum thickness of the cylinder. Projections of numbers of cylinders expected to fail various thickness criteria are computed from corrosion models relating minimum wall thickness to cylinder age, initial thickness estimates, and cylinder subpopulations defined in terms of plant site, yard, top or bottom storage positions, nominal thickness, etc. In this report, UT data collected during FY03 is combined with UT data collected in earlier years (FY94-FY02), and all of the data is inventoried chronologically and by various subpopulations. The UT data is used to fit models of maximum pit depth and minimum thickness, and the fitted models are used to extrapolate minimum thickness estimates into the future and in turn to compute

Simulation model for port shunting yards

Science.gov (United States)

Rusca, A.; Popa, M.; Rosca, E.; Rosca, M.; Dragu, V.; Rusca, F.

2016-08-01

Sea ports are important nodes in the supply chain, joining two high capacity transport modes: rail and maritime transport. The huge cargo flows transiting port requires high capacity construction and installation such as berths, large capacity cranes, respectively shunting yards. However, the port shunting yards specificity raises several problems such as: limited access since these are terminus stations for rail network, the in-output of large transit flows of cargo relatively to the scarcity of the departure/arrival of a ship, as well as limited land availability for implementing solutions to serve these flows. It is necessary to identify technological solutions that lead to an answer to these problems. The paper proposed a simulation model developed with ARENA computer simulation software suitable for shunting yards which serve sea ports with access to the rail network. Are investigates the principal aspects of shunting yards and adequate measures to increase their transit capacity. The operation capacity for shunting yards sub-system is assessed taking in consideration the required operating standards and the measure of performance (e.g. waiting time for freight wagons, number of railway line in station, storage area, etc.) of the railway station are computed. The conclusion and results, drawn from simulation, help transports and logistics specialists to test the proposals for improving the port management.

Prediction of External Corrosion for Steel Cylinders--2004 Report

Energy Technology Data Exchange (ETDEWEB)

Schmoyer, RLS

2004-07-07

Depleted uranium hexafluoride (UF{sub 6}) is stored in over 60,000 steel cylinders at the East Tennessee Technology Park (ETTP) in Oak Ridge, Tennessee, at the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and at the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The cylinders range in age from 4 to 53 years. Although when new the cylinders had wall thicknesses specified to within manufacturing tolerances, over the years corrosion has reduced their actual wall thicknesses. The UF{sub 6} Cylinder Project is managed by the United States Department of Energy (DOE) to safely maintain the UF{sub 6} and the cylinders containing it. This report documents activities that address UF{sub 6} Cylinder Project requirements and actions involving forecasting cylinder wall thicknesses. These requirements are delineated in the System Requirements Document (LMES 1997a), and the actions needed to fulfill them are specified in the System Engineering Management Plan (LMES 1997b). The report documents cylinder wall thickness projections based on models fit to ultrasonic thickness (UT) measurement data. UT data is collected at various locations on randomly sampled cylinders. For each cylinder sampled, the minimum UT measurement approximates the actual minimum thickness of the cylinder. Projections of numbers of cylinders expected to fail various thickness criteria are computed from corrosion models relating minimum wall thickness to cylinder age, initial thickness estimates, and cylinder subpopulations defined in terms of plant site, yard, top or bottom storage positions, nominal thickness, etc. In this report, UT data collected during FY03 is combined with UT data collected in earlier years (FY94-FY02), and all of the data is inventoried chronologically and by various subpopulations. The UT data is used to fit models of maximum pit depth and minimum thickness, and the fitted models are used to extrapolate minimum thickness estimates into the future and in

Chemical aspects of cylinder corrosion and a scenario for hole development

Energy Technology Data Exchange (ETDEWEB)

Barber, E.J. [Martin Marietta Energy Systems, Oak Ridge, TN (United States)

1991-12-31

In June 1990, two cylinders in the depleted UF{sub 6} cylinder storage yards at Portsmouth were discovered to have holes in their walls at the valve-end stiffening ring at a point below the level of the gas-solid interface of the UF{sub 6}. The cylinder with the larger hole, which extended under the stiffening ring, was stacked in a top row 13 years ago. The cylinder with the smaller hole had been stacked in a bottom row 4 years ago. The lifting lugs of the adjacent cylinders pointed directly at the holes. A Cylinder Investigating Committee was appointed to determine the cause or causes of the holes and to assess the implications of these findings. This report contains a listing of the chemically related facts established by the Investigating Committee with the cooperation of the Operations and Technical Support Divisions at the Portsmouth Gaseous Diffusion Plant, the scenario developed to explain these findings and some implications of this scenario. In summary, the interrelated reactions of water, solid UF{sub 6} and iron presented by R. L. Ritter are used to develop a scenario which explains the observations and deductions made during the investigation. The chemical processes are intimately related to the course of the last three of the four stages of hole development. A simple model is proposed which permits semiquantitative prediction of such information as the HF loss rates as a function of time, the rate of hole enlargement, the time to hydrolyze a cylinder of UF{sub 6} and the approximate size of the hole. The scenario suggests that the environmental consequences associated with a developing hole in a depleted UF{sub 6} cylinder are minimal for the first several years but will become significant if too many years pass before detection. The overall environmental picture is presented in more detail elsewhere.

Assessment of Reusing 14-Ton, Thin-Wall, Depleted UF6 Cylinders as LLW Disposal Containers

International Nuclear Information System (INIS)

O'Connor, D.G.; Poole, A.B.; Shelton, J.H.

2000-01-01

of 48 inches and nominally contain 14 tons (12.7 MT) of DUF 6 , were originally designed and fabricated for temporary storage of DUF 6 . They were fabricated from pressure-vessel-grade steels according to the provisions of the ASME Boiler and Pressure Vessel Code. Cylinders are stored in open yards at the three sites and, due to historical storage techniques, were subject to corrosion. Roughly 10,000 of the 14TTW cylinders are considered substandard due to corrosion and other structural anomalies caused by mishandling. This means that approximately 40,000 14TTW cylinders could be made available as containers for LLW disposal In order to demonstrate the use of 14TTW cylinders as LLW disposal containers, several qualifying tasks need to be performed. Two demonstrations are being considered using 14TTW cylinders--one demonstration using contaminated soil and one demonstration using U 3 O 8 . The objective of this report are to determine how much information is known that could be used to support the demonstrations, and how much additional work will need to be done in order to conduct the demonstrations. Information associated with the following four qualifying tasks are evaluated in this report

Optimizing yard operations in port container terminals

DEFF Research Database (Denmark)

Kallehauge, Louise Sibbesen

2005-01-01

This paper deals with the problem of positioning containers in a yard block of a port container terminal. The objective of the container positioning problem (CPP) is to minimise the total handling time in the block, i.e. the time required for storage and reshuffling of containers. One...

Prediction of External Corrosion for Steel Cylinders--2007 Report

Energy Technology Data Exchange (ETDEWEB)

Schmoyer, Richard L [ORNL

2008-01-01

Depleted uranium hexafluoride (DUF{sub 6}) is stored in over 62,000 containment cylinders at the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and at the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. Over 4,800 of the cylinders at Portsmouth were recently moved there from the East Tennessee Technology Park (ETTP) in Oak Ridge, Tennessee. The cylinders range in age up to 56 years and come in various models, but most are 48-inch diameter 'thin-wall'(312.5 mil) and 'thick-wall' (625 mil) cylinders and 30-inch diameter '30A' (including '30B') cylinders with 1/2-inch (500 mil) walls. Most of the cylinders are carbon steel, and they are subject to corrosion. The United States Department of Energy (DOE) manages the cylinders to maintain them and the DUF{sub 6} they contain. Cylinder management requirements are specified in the System Requirements Document (LMES 1997a), and the activities to fulfill them are specified in the System Engineering Management Plan (LMES 1997b). This report documents activities that address DUF{sub 6} cylinder management requirements involving measuring and forecasting cylinder wall thicknesses. As part of these activities, ultrasonic thickness (UT) measurements are made on samples of cylinders. For each sampled cylinder, multiple measurements are made in an attempt to find, approximately, the minimum wall thickness. Some cylinders have a skirt, which is an extension of the cylinder wall to protect the head (end) and valve. The head/skirt interface crevice is thought to be particularly vulnerable to corrosion, and for some skirted cylinders, in addition to the main body UT measurements, a separate suite of measurements is also made at the head/skirt interface. The main-body and head/skirt minimum thickness data are used to fit models relating minimum thickness to cylinder age, nominal thicknesses, and cylinder functional groups defined in terms of plant site, storage yard

700 bar hydrogen cylinder design, testing and certification

International Nuclear Information System (INIS)

Duncan, M.

2004-01-01

'Full text:' Light weight and high pressure cylinders for compressed hydrogen storage are essential components for fuel cell vehicles. Storage volume and mass are two key considerations. Current on-board hydrogen storage systems are based on a maximum pressure of 350 bar. While 350 bar systems are excellent solutions for many applications, some situations required higher storage densities due to space restrictions. As a result significant research and development work has been expended by cylinder manufacturers, systems providers, testing agencies and automotive manufacturers to develop 700 bar systems to reduce storage volume. Dynetek Industries Ltd has proactively developed a range of 700 bar storage cylinders based on a seamless aluminum liner over wrapped with a carbon fiber composite. This paper presents the challenges and processes involved in the design, testing and certification of the Dynetek Industries Ltd 700 bar cylinder. The paper also provides reasoning for further volume and mass optimization of compressed hydrogen cylinders by incorporating realistic cylinder usage parameters into standards. In particular the overly conservative fill life requirement for cylinders will be examined. (author)

Breached cylinder incident at the Portsmouth gaseous diffusion plant

Energy Technology Data Exchange (ETDEWEB)

Boelens, R.A. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

1991-12-31

On June 16, 1990, during an inspection of valves on partially depleted product storage cylinders, a 14-ton partially depleted product cylinder was discovered breached. The cylinder had been placed in long-term storage in 1977 on the top row of Portsmouth`s (two rows high) storage area. The breach was observed when an inspector noticed a pile of green material along side of the cylinder. The breach was estimated to be approximately 8- inches wide and 16-inches long, and ran under the first stiffening ring of the cylinder. During the continuing inspection of the storage area, a second 14-ton product cylinder was discovered breached. This cylinder was stacked on the bottom row in the storage area in 1986. This breach was also located adjacent to a stiffening ring. This paper will discuss the contributing factors of the breaching of the cylinders, the immediate response, subsequent actions in support of the investigation, and corrective actions.

Storage in pressurized cylinders of Kr adsorbed on activated carbon. Fundamental principles

International Nuclear Information System (INIS)

Henrion, P.N.; Greff, J.F. de; Claes, W.; Leurs, A.

1979-01-01

Pressure of a few kg/cm 2 cause considerable adsorption of krypton on charcoal. In presence of this adsorbent, the aspects of krypton storage in a pressurized cylinder are modified in such a way that, eventually, a simplified engineered storage can be based on this procedure. As fission krypton generates heat and since the amount adsorbed is a function of temperature and pressure, there is no easy way of assessing the value of this concept. The purpose of this study was therefore to review the types of charcoal commercially available to examine their properties as adsorbents, as well as the thermal conductivity and the packing efficiency obtainable in beds made of these materials. The ways in which data are measured or estimated are explained in some detail. Heat transfer was evaluated by a simple mathematical model and, by means of selected values from the above data, realistic examples were treated, leading to explicit relationships between wall temperature, pressure and useful krypton load. Influence of krypton specific activity ( 85 Kr dilution) was also examined. The pressure vessels diameter is however of fundamental importance. The authors strongly recommend the use of specially designed, light-weight, relatively narrow pressure cylinders

Y-12 old salvage yard scrap metal characterization study

International Nuclear Information System (INIS)

Anderson, L.M.; Melton, S.G.; Shaw, S.S.

1993-11-01

The purpose of the Y-12 Old Salvage Yard scrap metal Characterization Study is to make conservative estimates of the quantities of total uranium and the wt % 235 U contained in scrap metal. The original project scope included estimates of thorium, but due to the insignificant quantities found in the yards, thorium was excluded from further analysis. Metal in three of the four Y-12 scrap metal yards were characterized. The scrap metal yard east of the PIDAS fence is managed by the Environmental Restoration Program and therefore was not included in this study. For all Y-12 Plant scrap metal shipments, Waste Transportation, Storage, and Disposal (WTSD) personnel must complete a Request for Authorization to Ship Nuclear Materials, UCN-16409, which requires the grams of total uranium, the wt % 235 U, and the grams of 235 U contained in the shipment. This information is necessary to ensure compliance with Department of Transportation regulations, as well as to ensure that the receiving facility is adhering to its operating license. This characterization study was designed to provide a technical basis for determining these necessary radioactive quantities

28 CFR 25.56 - Responsibilities of junk yards and salvage yards and auto recyclers.

Science.gov (United States)

2010-07-01

... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Responsibilities of junk yards and salvage yards and auto recyclers. 25.56 Section 25.56 Judicial Administration DEPARTMENT OF JUSTICE... Responsibilities of junk yards and salvage yards and auto recyclers. (a) By no later than March 31, 2009, and...

A concept of a nonfissile uranium hexafluoride overpack for storage, transport, and processing of corroded cylinders

International Nuclear Information System (INIS)

Pope, R.B.; Cash, J.M.; Singletary, B.H.

1996-01-01

There is a need to develop a means of safely transporting breached 48-in. cylinders containing depleted uranium hexafluoride (UF 6 ) from current storage locations to locations where the contents can be safely removed. There is also a need to provide a method of safely and easily transporting degraded cylinders that no longer meet the US Department of Transportation (DOT) and American National Standards Institute, Inc., (ANSI) requirements for shipments of depleted UF 6 . A study has shown that an overpack can be designed and fabricated to satisfy these needs. The envisioned overpack will handle cylinder models 48G, 48X, and 48Y and will also comply with the ANSI N14.1 and the American Society of Mechanical Engineers (ASME) Sect. 8 requirements

A Convenient Storage Rack for Graduated Cylinders

Science.gov (United States)

Love, Brian

2004-01-01

An attempt is made to find a solution to the occasional problem of a need for storing large numbers of graduated cylinders in many teaching and research laboratories. A design, which involves the creation of a series of parallel channels that are used to suspend inverted graduated cylinders by their bases, is proposed.

Space-sharing Strategy for Building Dynamic Container Yard Storage Considering Uncertainty on Number of Incoming Containers

Directory of Open Access Journals (Sweden)

Siti Nurminarsih

2017-12-01

Full Text Available The implementation of AEC (Asian Economic Community leads to demand increase at ports in Indonesia. This increasing demand is followed by operational efficiency at the port as well. In fact, ports in Indonesia have an average dwell time for 5 days. One of the causes of this long dwell time is container transfer inefficiencies during loading process. In this research, we will focus in yard management and increasing land utilization. To increase the land utilization, we develop the space-sharing concept to reduce the initial space needed for a given workload. Since the ships arrivals are also varying, this concept will be possible. We develop the concept by adding uncertainty on number of incoming containers at operational level as the determining factor in planning a shared yard area. We propose a simulation approach to evaluate strategies in making yard template.

Fire exposure of empty 30B cylinders

Energy Technology Data Exchange (ETDEWEB)

Ziehlke, K.T. [MJB Technical Associates, Inc., Knoxville, TN (United States)

1991-12-31

Cylinders for UF{sub 6} handling, transport, and storage are designed and built as unfired pressure vessels under ASME Boiler and Pressure Vessel Code criteria and standards. They are normally filled and emptied while UF{sub 6} is in its liquid phase. Transport cylinders such as the Model 30B are designed for service at 200 psi and 250{degrees}F, to sustain the process conditions which prevail during filling or emptying operations. While in transport, however, at ambient temperature the UF{sub 6} is solid, and the cylinder interior is well below atmospheric pressure. When the cylinders contain isotopically enriched product (above 1.0 percent U-235), they are transported in protective overpacks which function to guard the cylinders and their contents against thermal or mechanical damage in the event of possible transport accidents. Two bare Model 30B cylinders were accidentally exposed to a storage warehouse fire in which a considerable amount of damage was sustained by stored materials and the building structure, as well as by the cylinder valves and valve protectors. The cylinders were about six years old, and had been cleaned, inspected, hydrotested, and re-certified for service, but were still empty at the time of the fire. The privately-owned cylinders were transferred to DOE for testing and evaluation of the fire damage.

Closure Report for Corrective Action Unit 481: Area 12 T-Tunnel Conditional Release Storage Yard, Nevada Test Site, Nevada

International Nuclear Information System (INIS)

2008-01-01

Corrective Action Unit (CAU) 481 is identified in the Federal Facility Agreement and Consent Order (FFACO) as Area 12 T-Tunnel Conditional Release Storage Yard. CAU 481 is located in Area 12 of the Nevada Test Site, which is approximately 65 miles northwest of Las Vegas, Nevada. This CAU consists of one Corrective Action Site (CAS), CAS 12-42-05, Housekeeping Waste. CAU 481 closure activities were conducted by the Defense Threat Reduction Agency from August 2007 through July 2008 according to the FFACO and Revision 3 of the Sectored Clean-up Work Plan for Housekeeping Category Waste Sites. Closure activities included removal and disposal of construction debris and low-level waste. Drained fluids, steel, and lead was recycled as appropriate. Waste generated during closure activities was appropriately managed and disposed.

Ascaris and hookworm transmission in preschool children from rural Panama: role of yard environment, soil eggs/larvae and hygiene and play behaviours.

Science.gov (United States)

Krause, Rachel J; Koski, Kristine G; Pons, Emérita; Sandoval, Nidia; Sinisterra, Odalis; Scott, Marilyn E

2015-10-01

This study explored whether the yard environment and child hygiene and play behaviours were associated with presence and intensity of Ascaris and hookworm in preschool children and with eggs and larvae in soil. Data were collected using questionnaires, a visual survey of the yard, soil samples and fecal samples collected at baseline and following re-infection. The presence of eggs/larvae in soil was associated negatively with water storage (eggs) but positively with dogs (eggs) and distance from home to latrine (larvae). Baseline and re-infection prevalences were: hookworm (28.0%, 3.4%); Ascaris (16.9%, 9.5%); Trichuris (0.9%, 0.7%). Zero-inflated negative binomial regression models revealed a higher baseline hookworm infection if yards had eggs or larvae, more vegetation or garbage, and if the child played with soil. Baseline Ascaris was associated with dirt floor, dogs, exposed soil in yard, open defecation and with less time playing outdoors, whereas Ascaris re-infection was associated with water storage, vegetation cover and garbage near the home and not playing with animals. Our results show complex interactions between infection, the yard environment and child behaviours, and indicate that transmission would be reduced if latrines were closer to the home, and if open defecation and water spillage were reduced.

40 CFR 60.1915 - What is yard waste?

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What is yard waste? 60.1915 Section 60... Municipal Waste Combustion Units Constructed on or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1915 What is yard waste? Yard waste is grass, grass...

40 CFR 62.15370 - What is yard waste?

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false What is yard waste? 62.15370 Section 62... for Small Municipal Waste Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15370 What is yard waste? Yard waste is grass, grass...

Superfund record of decision (EPA Region 3): Paoli Rail Yard, Paoli, PA. (First remedial action), July 1992. Final report

International Nuclear Information System (INIS)

1992-01-01

The 428-acre Paoli Rail Yard site is a maintenance, storage, and repair facility located north of Paoli in Chester County, Pennsylvania. Soil contamination in and around the car shop is attributed to releases of fuel oil and PCB-laden transformer fluid from rail cars during maintenance and repair activities. In 1985, EPA identified PCB contamination in soil and sediment, and on building surfaces. The rail companies agreed to address site clean-up activities, including erosion, sedimentation, and stormwater characteristics and control, decontamination, soil sampling, excavation of 3,500 cubic yards residential soil, and implementation of worker protection measures. The ROD provides a final remedy for contaminated soil (from the rail yard and residences), sediment, and structures at the Paoli Rail Yard, and contaminated ground water. The primary contaminants of concern affecting the soil, sediment, debris, and ground water are VOCs, including benzene, ethylbenzene, toluene, xylenes; and other organics, including PCBs. The selected remedial action for the site are included

76 FR 58167 - Safety Standard for Play Yards

Science.gov (United States)

2011-09-20

... subject matter expert. Thus, EWS contains the best data to support the play yard regulatory work. 1... compressed the airway. One toddler was killed when the play yard collapsed unexpectedly. The child was... hospitalization was caused by the presence of soft bedding in the play yard. This was a severe injury to a 7-week...

Long-term storage of recovered krypton

International Nuclear Information System (INIS)

Horii, Yuji; Yamamoto, Yoshimasa

1983-01-01

Various storage methods for krypton-85 recovered from a nuclear fuel reprocessing plant are under development in many countries. These methods include:(1) direct storage in pressurized cylinders, (2) storage of krypton adsorbed on charcoal or zeolite in pressurized cylinders and (3) immobilization (encapsulation) in zeolite. A krypton storage facility using pressurized cylinders has been constructed in the krypton recovery pilot plant in Tokaimura and other methods are now under development. These three methods are evaluated and the features of the constructed facility are also reported. (author)

American black bears and bee yard depredation at Okefenokee Swamp, Georgia

Science.gov (United States)

Clark, J.D.; Dobey, S.; Masters, D.V.; Scheick, B.K.; Pelton, M.R.; Sunquist, M.E.

2005-01-01

We studied American black bears (Ursus americanus), on the northwest periphery of Okefenokee Swamp in southeast Georgia, to assess landowner attitudes toward bears, estimate the extent of damage to commercial honey bee operations by bears, and evaluate methods to reduce bear depredations to apiaries. We collected 8,351 black bear radiolocations and identified 51 bee yards on our study area. Twenty-seven of 43 home ranges contained ≥1 bee yard, averaging 11.3 and 5.1 bee yards/home range of males (n = 7) and females (n = 20), respectively. From 1996 to 1998, we documented 7 instances of bears raiding bee yards within our study area and 6 instances in adjacent areas. All but 1 of the 13 raided yards were enclosed by electric fencing. In the 12 cases of damage to electrically fenced yards, however, the fences were not active because of depleted batteries. Based on compositional analysis, bear use of areas 800–1,400 m from bee yards was disproportionately greater than use 0–800 m from bee yards. Bears disproportionately used bay (red bay: Persea borbonia, loblolly bay: Gordonia lasianthus, and southern magnolia: Magnolia virginia), gum (water tupelo: Nyssa aquatic and black gum: N. sylvatica), and cypress (Taxodium spp.) and loblolly bay habitats, however, compared with slash pine (Pinus elliottii) or pine–oak (Quercus spp.), where bee yards usually were placed. The distribution of bear radiolocations likely reflected the use of those swamp and riparian areas, rather than avoidance of bee yards. Distances to streams from damaged bee yards (x̄ = 1,750 m) were less than from undamaged yards (x̄ = 4,442 m), and damaged bee yards were closer to unimproved roads (x̄ = 134 m) than were undamaged bee yards (x̄ = 802 m). Our analysis suggests that bee yard placement away from bear travel routes (such as streams and unimproved roads) can reduce bear depredation problems. Our results strongly indicate that working electric fences are effective deterrents to bear

An Agent-Based Solution Framework for Inter-Block Yard Crane Scheduling Problems

Directory of Open Access Journals (Sweden)

Omor Sharif

2012-06-01

Full Text Available The efficiency of yard operations is critical to the overall productivity of a container terminal because the yard serves as the interface between the landside and waterside operations. Most container terminals use yard cranes to transfer containers between the yard and trucks (both external and internal. To facilitate vessel operations, an efficient work schedule for the yard cranes is necessary given varying work volumes among yard blocks with different planning periods. This paper investigated an agent-based approach to assign and relocate yard cranes among yard blocks based on the forecasted work volumes. The goal of our study is to reduce the work volume that remains incomplete at the end of a planning period. We offered several preference functions for yard cranes and blocks which are modeled as agents. These preference functions are designed to find effective schedules for yard cranes. In addition, we examined various rules for the initial assignment of yard cranes to blocks. Our analysis demonstrated that our model can effectively and efficiently reduce the percentage of incomplete work volume for any real-world sized problem.

Retrievable surface storage: interim storage of solidified high-level waste

International Nuclear Information System (INIS)

LaRiviere, J.R.; Nelson, D.C.

1976-01-01

Studies have been conducted on retrievable-surface-storage concepts for the interim storage of solidified high-level wastes. These studies have been reviewed by the Panel on Engineered Storage, convened by the Committee on Radioactive Waste Management of the National Research Council-National Academy of Sciences. The Panel has concluded that ''retrievable surface storage is an acceptable interim stage in a comprehensive system for managing high-level radioactive wastes.'' The scaled storage cask concept, which was recommended by the Panel on Engineered Storage, consists of placing a canister of waste inside a carbon-steel cask, which in turn is placed inside a thick concrete cylinder. The waste is cooled by natural convection air flow through an annulus between the cask and the inner wall of the concrete cylinder. The complete assembly is placed above ground in an outdoor storage area

49 CFR 232.217 - Train brake tests conducted using yard air.

Science.gov (United States)

2010-10-01

... reduction of brake pipe air pressure at the same, or slower, rate as an engineer's brake valve. (b) The yard... 49 Transportation 4 2010-10-01 2010-10-01 false Train brake tests conducted using yard air. 232... Train brake tests conducted using yard air. (a) When a train air brake system is tested from a yard air...

Gardening/Yard Work and Depressive Symptoms in African Americans.

Science.gov (United States)

Torres, Elisa R; Sampselle, Carolyn M; Ronis, David L; Neighbors, Harold W; Gretebeck, Kimberlee A

2016-04-01

The purpose of this study was to examine the frequency of gardening/yard work in relation to depressive symptoms in African-Americans while controlling for biological and social factors. A secondary analysis was performed on the National Survey of American Life (n=2,903) using logistic regression for complex samples. Gardening/Yard work was measured by self-reported frequency. Depressive symptoms were measured with the Center for Epidemiologic Studies Depression scale. Biological and social factors, not gardening/yard work, were associated with depressive symptoms. Biological and social factors may need to be addressed before the association between gardening/yard work and depressive symptoms can be determined. Copyright © 2015 Elsevier Inc. All rights reserved.

Corrective Action Investigation Plan for Corrective Action Unit 166: Storage Yards and Contaminated Materials, Nevada Test Site, Nevada

International Nuclear Information System (INIS)

David Strand

2006-01-01

Corrective Action Unit 166 is located in Areas 2, 3, 5, and 18 of the Nevada Test Site, which is 65 miles northwest of Las Vegas, Nevada. Corrective Action Unit (CAU) 166 is comprised of the seven Corrective Action Sites (CASs) listed below: (1) 02-42-01, Cond. Release Storage Yd - North; (2) 02-42-02, Cond. Release Storage Yd - South; (3) 02-99-10, D-38 Storage Area; (4) 03-42-01, Conditional Release Storage Yard; (5) 05-19-02, Contaminated Soil and Drum; (6) 18-01-01, Aboveground Storage Tank; and (7) 18-99-03, Wax Piles/Oil Stain. These sites are being investigated because existing information on the nature and extent of potential contamination is insufficient to evaluate and recommend corrective action alternatives. Additional information will be obtained by conducting a corrective action investigation (CAI) before evaluating corrective action alternatives and selecting the appropriate corrective action for each CAS. The results of the field investigation will support a defensible evaluation of viable corrective action alternatives that will be presented in the Corrective Action Decision Document. The sites will be investigated based on the data quality objectives (DQOs) developed on February 28, 2006, by representatives of the Nevada Division of Environmental Protection; U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office; Stoller-Navarro Joint Venture; and Bechtel Nevada. The DQO process was used to identify and define the type, amount, and quality of data needed to develop and evaluate appropriate corrective actions for CAU 166. Appendix A provides a detailed discussion of the DQO methodology and the DQOs specific to each CAS. The scope of the CAI for CAU 166 includes the following activities: (1) Move surface debris and/or materials, as needed, to facilitate sampling. (2) Conduct radiological surveys. (3) Perform field screening. (4) Collect and submit environmental samples for laboratory analysis to determine if

40 CFR 60.1440 - What is yard waste?

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What is yard waste? 60.1440 Section 60...) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Small Municipal Waste... Reconstruction is Commenced After June 6, 2001 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60...

FACSIM/MRS [Monitored Retrievable Storage]-2: Storage and shipping model documentation and user's guide

International Nuclear Information System (INIS)

Huber, H.D.; Chockie, A.D.; Hostick, C.J.; Otis, P.T.; Sovers, R.A.

1987-06-01

The Pacific Northwest Laboratory (PNL) has developed a stochastic computer model, FACSIM/MRS, to assist in assessing the operational performance of the Monitored Retrievable Storage (MRS) waste-handling facility. This report provides the documentation and user's guide for FACSIM/MRS-2, which is also referred to as the back-end model. The FACSIM/MRS-2 model simulates the MRS storage and shipping operations, which include handling canistered spent fuel and secondary waste in the shielded canyon cells, in onsite yard storage, and in repository shipping cask loading areas

UF6 Cylinder Imaging by Fast Neutron Transmission Tomography

International Nuclear Information System (INIS)

McElroy, R.; Hausladen, P.; Blackston, M.; Croft, S.

2015-01-01

The common use Non-Destructive Assay techniques for the determination of 235 U enrichment and mass of UF6 cylinders used in the production of nuclear reactor fuel require prior knowledge of the physical distribution of the UF6 within the cylinder. The measurement performance for these techniques is typically evaluated based on assumed bounding case distributions of the material. However, little direct data such as radiographic or tomographic images, regarding the distribution of the UF6 within the cylinder is available against which to judge these assumptions. We have developed and tested a prototype active neutron tomographic imaging system employing an Associated Particle Imaging (API) neutron generator and an array of pixelated neutron scintillation counters. This system has been successfully used to obtain the 3-dimensional map of the distribution of UF6 within a type 12B storage cylinder. Results from these measurements are presented and the potential performance and utility of this technique with larger 30B and 48Y cylinders is discussed. (author)

Atlanta Rail Yard Study: Evaluation of local-scale air pollution ...

Science.gov (United States)

Intermodal rail yards are important nodes in the freight transportation network, where freight is organized and moved from one mode of transport to another, critical equipment is serviced, and freight is routed to its next destination. Rail yard environments are also areas with multiple sources of air pollutant emissions (e.g., heavy-duty vehicles, locomotives, cranes), which may affect local air quality in residential areas nearby. In order to understand emissions and related air quality impacts, two field studies took place over the time span of 2010-2012 to measure air pollution trends in close proximity to the Inman and Tilford rail yard complex in Atlanta, GA. One field study involved long-term stationary monitoring of black carbon, fine particles, and carbon dioxide at two stations nearby the rail yard. In addition, a second field study performed intensive mobile air monitoring for a one month period in the summer of 2012 at a roadway network surrounding the rail yard complex and measured a comprehensive array of pollutants. Real-time mobile particulate measurements included particle counts, extinction coefficient, black carbon via light-absorption and particle incandescence, and particle composition derived by aerosol mass spectrometry. Gas-phase measurements included oxides of nitrogen, sulfur dioxide, carbon dioxide, and air toxics (e.g., benzene). Both sets of measurements determined detectable local influence from rail yard-related emissions.

Scheduling freight trains in rail-rail transshipment yards

OpenAIRE

Nils Boysen; Erwin Pesch

2008-01-01

Transshipment yards, where gantry cranes allow for an effcient transshipment of containers between different freight trains, are important entities in modern railway systems and facilitate the general shift from point-to-point transport to hub-and-spoke railway systems. Modern rail-rail transshipment yards accelerate container handling, so that multiple smaller trains with equal destination can be consolidated to a reduced number of trains without jeopardizing on time deliveries. An important...

FACSIM/MRS (Monitored Retrievable Storage)-2: Storage and shipping model documentation and user's guide

Energy Technology Data Exchange (ETDEWEB)

Huber, H.D.; Chockie, A.D.; Hostick, C.J.; Otis, P.T.; Sovers, R.A.

1987-06-01

The Pacific Northwest Laboratory (PNL) has developed a stochastic computer model, FACSIM/MRS, to assist in assessing the operational performance of the Monitored Retrievable Storage (MRS) waste-handling facility. This report provides the documentation and user's guide for FACSIM/MRS-2, which is also referred to as the back-end model. The FACSIM/MRS-2 model simulates the MRS storage and shipping operations, which include handling canistered spent fuel and secondary waste in the shielded canyon cells, in onsite yard storage, and in repository shipping cask loading areas.

Sequential batch anaerobic composting of municipal solid waste (MSW) and yard waste

Energy Technology Data Exchange (ETDEWEB)

O' Keefe, D.M.; Chynoweth, D.P.; Barkdoll, A.W.; Nordstedt, R.A.; Owens, J.M.; Sifontes, J. (Florida Univ., Gainesville, FL (United States). Dept. of Agricultural Engineering)

1993-01-01

Sequential batch anaerobic composting (SEBAC[sup TM]) was used to treat two fractions of municipal solid waste (MSW), the organic fraction of the MSW (processed MSW) and yard waste. Processed MSW gave a mean methane yield of 0.19 m[sup 3] kg[sup -1] volatile solids (VS) after 42 days. The mean VS reduction was 49.7% for this same period. Yard waste gave a mean methane yield of 0.07 m[sup 3] kg[sup -1] VS. Methane content of the biogas stabilized at a mean of 48% from three to four days after startup. The mean VS reduction for yard waste was 19%. With processed MSW, the volatile acid concentration was over 3000 mg L[sup -1] during startup but these acids were reduced within a few days to negligible levels. The trend was similar with yard waste except that volatile acids reached maximum concentrations of less than 1000 mg L[sup -1]. Composts from the reactors were evaluated for agronomic characteristics and pollution potential. Processed MSW and yard waste residues had marginal fertilizer value but posed no potential for groundwater pollution. Yard waste residue caused no apparent inhibition to mustard (Brassica juncea) germination relative to a commercial growth medium. Anaerobic yard waste compost demonstrated the potential to improve the water holding capacity of Florida soils. (author)

Development of long term storage technique for recovered Kr-85, (1)

International Nuclear Information System (INIS)

Inada, Eiichi; Motoyama, Shigeji; Tsunoda, Naomi; Yamamoto, Keizo; Hirano, Seiji.

1979-01-01

The adsorption storage method of radioactive krypton Kr-85 using a double cylinder packed with activated charcoal is expected to be put into practical use as an intermediate storing method until the immobilization technique for long term storage is established. In this paper, the conceptual design of an intermediate, remote-controlled Kr-85 storage facility is presented. The features of this system are double containment, low pressure storage, and remote control. Kr-85 is at first filled into a double cylinder by the adsorbing effect of activated charcoal at low temperature (-196 deg C) by cooling with liquid nitrogen. Then, the unwelded portion of the outer cylinder containing the inner cylinder is welded and inspected to make double containment. The double cylinders are cooled by ventilation to remove the decay heat of Kr-85, and krypton leakage is always monitored. If any leakage is detected, the double cylinder is transferred to the cutting cell for the re-encapsulation of Kr-85 in a safe double cylinder. All operations are performed by remote control because of a high radiation field. The expected amount and composition of Kr-85 to be recovered from the reprocessing plant are also given as the design conditions. (Wakatsuki, Y.)

Determining average yarding distance.

Science.gov (United States)

Roger H. Twito; Charles N. Mann

1979-01-01

Emphasis on environmental and esthetic quality in timber harvesting has brought about increased use of complex boundaries of cutting units and a consequent need for a rapid and accurate method of determining the average yarding distance and area of these units. These values, needed for evaluation of road and landing locations in planning timber harvests, are easily and...

Global Monitoring Of Uranium Hexifloride Cylinders Next Steps In Development Of An Action Plan

International Nuclear Information System (INIS)

Hanks, D.

2010-01-01

Over 40 industrial facilities world-wide use standardized uranium hexafluoride (UF 6 ) cylinders for transport, storage and in-process receiving in support of uranium conversion, enrichment and fuel fabrication processes. UF 6 is processed and stored in the cylinders, with over 50,000 tU of UF 6 transported each year in these International Organization for Standardization (ISO) qualified containers. Although each cylinder is manufactured to an ISO standard that calls for a nameplate with the manufacturer's identification number (ID) and the owner's serial number engraved on it, these can be quite small and difficult to read. Recognizing that each facility seems to use a different ID, a cylinder can have several different numbers recorded on it by means of metal plates, sticky labels, paint or even marker pen as it travels among facilities around the world. The idea of monitoring movements of UF 6 cylinders throughout the global uranium fuel cycle has become a significant issue among industrial and safeguarding stakeholders. Global monitoring would provide the locations, movements, and uses of cylinders in commercial nuclear transport around the world, improving the efficiency of industrial operations while increasing the assurance that growing nuclear commerce does not result in the loss or misuse of cylinders. It should be noted that a unique ID (UID) attached to a cylinder in a verifiable manner is necessary for safeguarding needs and ensuring positive ID, but not sufficient for an effective global monitoring system. Modern technologies for tracking and inventory control can pair the UID with sensors and secure data storage for content information and complete continuity of knowledge over the cylinder. This paper will describe how the next steps in development of an action plan for employing a global UF 6 cylinder monitoring network could be cultivated using four primary UID functions - identification, tracking, controlling, and accounting.

Low-cost, low-weight CNG cylinder development. Final report

Energy Technology Data Exchange (ETDEWEB)

Richards, Mark E.; Melford, K.; Wong, J.; Gambone, L.

1999-09-01

This program was established to develop and commercialize new high-strength steel-lined, composite hoop-wrapped compressed natural gas (CNG) cylinders for vehicular applications. As much as 70% of the cost of natural gas vehicles can be related to on-board natural gas storage costs. The cost and weight targets for this program represent significant savings in each characteristic when compared to comparable containers available at the initiation of the program. The program objectives were to optimize specific weight and cost goals, yielding CNG cylinders with dimensions that should, allowing for minor modifications, satisfy several vehicle market segments. The optimization process encompassed material, design, and process improvement. In optimizing the CNG cylinder design, due consideration was given to safety aspects relative to national, international, and vehicle manufacturer cylinder standards and requirements. The report details the design and development effort, encompassing plant modifications, material selection, design issues, tooling development, prototype development, and prototype testing. Extenuating circumstances prevented the immediate commercialization of the cylinder designs, though significant progress was made towards improving the cost and performance of CNG cylinders. A new low-cost fiber was successfully employed while the weight target was met and the cost target was missed by less than seven percent.

Sediments of a retting yard

Digital Repository Service at National Institute of Oceanography (India)

Remani, K.N.; Venugopal, P.; Devi, K.S.; Unnithan, R.V.

(av. 46.8 and 92.3 mg/g respectively) compared to the reference station (20.6 and 48.9 mg/g) and published data on estuarine sediments.C/N ratios were consistently higher in the retting yard. Organic nitrogen, however,did not show this trend. Annual...

Storage Optimization for Export Containers in the Port of Izmir

Directory of Open Access Journals (Sweden)

Deniz Türsel Eliiyi

2013-07-01

Full Text Available In this study, we consider a real-life export container storage problem at an important container terminal in the Port of Izmir, Turkey. Currently, the container storage decisions at the port are taken by operators manually, which leads to continuous unnecessary re-handling movements of the containers. High transportation costs, waste of time, and inefficient capacity utilization in the container storage area are the consequences of non-optimal decisions. The main goal of this study is to minimize the transportation costs and the number of re-handling moves while storing the export containers at the terminal yard. We formulate the problem in two stages. While the first stage assigns the containers of the same vessel to a group of yard bays via an optimization model, the second stage decides on the exact location of each container with the help of an efficient heuristic approach. The experimental results with real data are presented and discussed.

Processing mixed-waste compressed-gas cylinders at the Oak Ridge Reservation

International Nuclear Information System (INIS)

Morris, M.I.; Conley, T.B.; Osborne-Lee, I.W.

1998-05-01

Until recently, several thousand kilograms of compressed gases were stored at the Oak Ridge Reservation (ORR), in Oak Ridge, Tennessee, because these cylinders could not be taken off-site in their state of configuration for disposal. Restrictions on the storage of old compressed-gas cylinders compelled the Waste Management Organization of Lockheed Martin Energy Systems, Inc. (LMES) to dispose of these materials. Furthermore, a milestone in the ORR Site Treatment Plan required repackaging and shipment off-site of 21 cylinders by September 30, 1997. A pilot project, coordinated by the Chemical Technology Division (CTD) at the Oak Ridge National Laboratory (ORNL), was undertaken to evaluate and recontainerize or neutralize these cylinders, which are mixed waste, to meet that milestone. Because the radiological component was considered to be confined to the exterior of the cylinder, the contents (once removed from the cylinder) could be handled as hazardous waste, and the cylinder could be handled as low-level waste (LLW). This pilot project to process 21 cylinders was important because of its potential impact. The successful completion of the project provides a newly demonstrated technology which can now be used to process the thousands of additional cylinders in inventory across the DOE complex. In this paper, many of the various aspects of implementing this project, including hurdles encountered and the lessons learned in overcoming them, are reported

A stakeless yard long bean cultivar derived from an interspecific cross between cowpea Vigna unguiculata L. (Walp) and yard long bean Vigna sesquipedalis L. (Verdc.)

International Nuclear Information System (INIS)

Luadthong, Sanit

1990-01-01

Full text: 'Yard long bean' is an important vegetable in the Thai diet, particularly in Northeast Thailand. However, growing 'yard long beans' requires stakes for supporting the twining stems and keeping the pod from touching the ground. Staking costs money, takes time and needs labour. An ideal cultivar would be a 'yard long bean' with erect plant type and under 80 cm in height that produces typical long bean pods and allows convenient picking during the harvest time. An attempt to breed such a cultivar was made by crossing cowpea Vigna unguiculata L. (Walp.) with' yard long bean' Vigna sesquipedalis L. (Verdc.) in 1984. This resulted in a new cultivar 'KKU 25'. This cultivar, having erect plant type, requires no staking for supporting the stem and produces long fresh pods with acceptable taste which can be harvested within 43 days. The average pod length is 48 cm, and pod diameter 1.43 cm. In a preliminary yield trial, an average fresh pod yield of 16 t/ha was obtained. (author)

Processing of mixed-waste compressed-gas cylinders on the Oak Ridge Reservation

International Nuclear Information System (INIS)

Morris, M.I.; Conley, T.B.; Osborne-Lee, I.W.

1998-03-01

To comply with restrictions on the storage of old compressed gas cylinders, the environmental management organization of Lockheed Martin Energy Systems must dispose of several thousand kilograms of compressed gases stored on the Oak Ridge Reservation (ORR) because the cylinders cannot be taken off-site for disposal in their current configuration. In the ORR Site Treatment Plan, a milestone is cited that requires repackaging and shipment off-site of 21 cylinders by September 30, 1997. A project was undertaken to first evaluate and then either recontainerize or neutralize these cylinders using a transportable compressed gas recontainerization skid (TCGRS), which was developed by Integrated Environmental Services of Atlanta. The transportable system can: (1) sample, analyze, and identify at the site the chemical and radiological content of each cylinder, even those with inoperable valves; (2) breach cylinders, when necessary, to release their contents into a containment chamber; and (3) either neutralize the gas or liquid contents within the containment chamber or transfer the gas or liquids to a new cylinder. The old cylinders and cylinder fragments were disposed of and the gases neutralized or transferred to new cylinders for transportation off-site for disposal. The entire operation to process the 21 cylinders took place in only 5 days once the system was approved for operation. The system performed as expected and can now be used to process the potentially thousands of more cylinders located across the US Department of Energy (DOE) complex that have not yet been declared surplus

Socioeconomic drivers of yard sustainable practices in a tropical city

Directory of Open Access Journals (Sweden)

Elvia J. Meléndez-Ackerman

2014-09-01

Full Text Available A growing body of work has emphasized the importance of residential areas to the overall green infrastructure of cities and recognizes that outcomes related to these areas are best studied using a social-ecological approach. We conducted vegetation surveys to evaluate yard practices that relate to the state of the yard vegetation, including species diversity and abundance, vegetation structure, and the percent of green area of yards versus paved areas, at the Río Piedras watershed within the San Juan metropolitan area. We used concomitant social household surveys to evaluate the association of social-economic and demographic factors at the household scale with these vegetation characteristics, as well as with landscape-level characteristics related to urban morphology and elevation. Our results for this tropical site were consistent with studies elsewhere in that a greater number of social factors at the household scale were more important in explaining the traits related to how green the yards were. On the other hand, we failed to detect the so-called luxury effect on urban vegetation encountered at many sites. Instead, we found consistent vegetation associations with the age of the residents, housing ownership, and, most importantly, with yard size. We have discussed the potential reasons for these discrepancies and the potential consequences of the human-natural links at the household scale to the future dynamics of this portion of the green infrastructure within this urban watershed.

Corrective Action Investigation Plan for Corrective Action Unit 166: Storage Yards and Contaminated Materials, Nevada Test Site, Nevada, Rev. No.: 0

Energy Technology Data Exchange (ETDEWEB)

David Strand

2006-06-01

Corrective Action Unit 166 is located in Areas 2, 3, 5, and 18 of the Nevada Test Site, which is 65 miles northwest of Las Vegas, Nevada. Corrective Action Unit (CAU) 166 is comprised of the seven Corrective Action Sites (CASs) listed below: (1) 02-42-01, Cond. Release Storage Yd - North; (2) 02-42-02, Cond. Release Storage Yd - South; (3) 02-99-10, D-38 Storage Area; (4) 03-42-01, Conditional Release Storage Yard; (5) 05-19-02, Contaminated Soil and Drum; (6) 18-01-01, Aboveground Storage Tank; and (7) 18-99-03, Wax Piles/Oil Stain. These sites are being investigated because existing information on the nature and extent of potential contamination is insufficient to evaluate and recommend corrective action alternatives. Additional information will be obtained by conducting a corrective action investigation (CAI) before evaluating corrective action alternatives and selecting the appropriate corrective action for each CAS. The results of the field investigation will support a defensible evaluation of viable corrective action alternatives that will be presented in the Corrective Action Decision Document. The sites will be investigated based on the data quality objectives (DQOs) developed on February 28, 2006, by representatives of the Nevada Division of Environmental Protection; U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office; Stoller-Navarro Joint Venture; and Bechtel Nevada. The DQO process was used to identify and define the type, amount, and quality of data needed to develop and evaluate appropriate corrective actions for CAU 166. Appendix A provides a detailed discussion of the DQO methodology and the DQOs specific to each CAS. The scope of the CAI for CAU 166 includes the following activities: (1) Move surface debris and/or materials, as needed, to facilitate sampling. (2) Conduct radiological surveys. (3) Perform field screening. (4) Collect and submit environmental samples for laboratory analysis to determine if

Physical properties and heat transfer characteristics of materials for krypton-85 storage

International Nuclear Information System (INIS)

Christensen, A.B.

1977-09-01

Krypton-85 decay results in heat generation, and the subsequent temperature increase in the krypton-85 storage media must be evaluated. This report compiles the physical properties of krypton and of potential krypton-85 storage materials which are required to calculate the maximum temperature developed during storage. Temperature calculations were made for krypton-85 stored as a gas or immobilized solid in steel storage cylinders. The effects of krypton-85 loading, cylinder radius, storage media properties, and exterior cooling on storage temperature were shown

Depleted uranium hexafluoride (DUF6) management system--a decision tool

International Nuclear Information System (INIS)

Gasper, J.R.; Sutter, R.J.; Avci, H.I.

1995-01-01

The Depleted Uranium Hexafluoride (DUF 6 ) Management System (DMS) is being developed as a decision tool to provide cost and risk data for evaluation of short-and long-term management strategies for depleted uranium. It can be used to assist decision makers on a programmatic or site-specific level. Currently, the DMS allows evaluation of near-term cylinder management strategies such as storage yard improvements, cylinder restocking, and reconditioning. The DMS has been designed to provide the user with maximum flexibility for modifying data and impact factors (e.g., unit costs and risk factors). Sensitivity analysis can be performed on all key parameters such as cylinder corrosion rate, inspection frequency, and impact factors. Analysis may be conducted on a system-wide, site, or yard basis. The costs and risks from different scenarios may be compared in graphic or tabular format. Ongoing development of the DMS will allow similar evaluation of long-term management strategies such as conversion to other chemical forms. The DMS is a Microsoft Windows 3.1 based, stand-alone computer application. It can be operated on a 486 or faster computer with VGA, 4 MB of RAM, and 10 MB of disk space

Preliminary Concept of Operations for a Global Cylinder Identification and Monitoring System

Energy Technology Data Exchange (ETDEWEB)

Whitaker, J. M. [ORNL; White-Horton, J. L. [ORNL; Morgan, J. B. [InSolves Associates

2013-08-01

This report describes a preliminary concept of operations for a Global Cylinder Identification and Monitoring System that could improve the efficiency of the International Atomic Energy Agency (IAEA) in conducting its current inspection activities and could provide a capability to substantially increase its ability to detect credible diversion scenarios and undeclared production pathways involving UF6 cylinders. There exist concerns that a proliferant State with access to enrichment technology could obtain a cylinder containing natural or low-enriched uranium hexafluoride (UF6) and produce a significant quantity (SQ)1 of highly enriched uranium in as little as 30 days. The National Nuclear Security Administration (NNSA) through the Next Generation Safeguards Initiative sponsored a multi-laboratory team to develop an integrated system that provides for detecting scenarios involving 1) diverting an entire declared cylinder for enrichment at a clandestine facility, 2) misusing a declared cylinder at a safeguarded facility, and 3) using an undeclared cylinder at a safeguarded facility. An important objective in developing this integrated system was to improve the timeliness for detecting the cylinder diversion and undeclared production scenarios. Developing this preliminary concept required in-depth analyses of current operational and safeguards practices at conversion, enrichment, and fuel fabrication facilities. The analyses evaluated the processing, movement, and storage of cylinders at the facilities; the movement of cylinders between facilities (including cylinder fabrication); and the misuse of safeguarded facilities.

Yards face up to future

International Nuclear Information System (INIS)

Bru, Jan Gunnar

1997-01-01

The article puts the attention to market relations in connection with the Norwegian petroleum industry. The paradox facing Norwegian yards involved in the offshore industry is that while the sector is now experiencing a market boom, within two years contractors could find themselves scrambling for work in a reduced market. 1 tab

GLOBAL MONITORING OF URANIUM HEXIFLORIDE CYLINDERS NEXT STEPS IN DEVELOPMENT OF AN ACTION PLAN

Energy Technology Data Exchange (ETDEWEB)

Hanks, D.

2010-06-09

Over 40 industrial facilities world-wide use standardized uranium hexafluoride (UF{sub 6}) cylinders for transport, storage and in-process receiving in support of uranium conversion, enrichment and fuel fabrication processes. UF{sub 6} is processed and stored in the cylinders, with over 50,000 tU of UF{sub 6} transported each year in these International Organization for Standardization (ISO) qualified containers. Although each cylinder is manufactured to an ISO standard that calls for a nameplate with the manufacturer's identification number (ID) and the owner's serial number engraved on it, these can be quite small and difficult to read. Recognizing that each facility seems to use a different ID, a cylinder can have several different numbers recorded on it by means of metal plates, sticky labels, paint or even marker pen as it travels among facilities around the world. The idea of monitoring movements of UF{sub 6} cylinders throughout the global uranium fuel cycle has become a significant issue among industrial and safeguarding stakeholders. Global monitoring would provide the locations, movements, and uses of cylinders in commercial nuclear transport around the world, improving the efficiency of industrial operations while increasing the assurance that growing nuclear commerce does not result in the loss or misuse of cylinders. It should be noted that a unique ID (UID) attached to a cylinder in a verifiable manner is necessary for safeguarding needs and ensuring positive ID, but not sufficient for an effective global monitoring system. Modern technologies for tracking and inventory control can pair the UID with sensors and secure data storage for content information and complete continuity of knowledge over the cylinder. This paper will describe how the next steps in development of an action plan for employing a global UF{sub 6} cylinder monitoring network could be cultivated using four primary UID functions - identification, tracking, controlling, and

The electrical resistance of enamel-dentine cylinders. Influence of NaCl content in storage solutions

NARCIS (Netherlands)

Gente, M; Pieper, K; Arends, J

Objectives. To investigate the influence of different electrolyte concentrations on the electrical resistance of sound human enamel-dentine cylinders in vitro. Methods: Forty cylinders of 3-mm diameter and 2-mm length were drilled from 40 extracted caries-free third molar teeth. For ease of handling

Prediction of External Corrosion for Steel Cylinders--2002 Report

International Nuclear Information System (INIS)

Schmoyer, RLS

2002-01-01

The United States Department of Energy (DOE) manages the UF 6 Cylinder Project. The project was formed to maintain and safely manage the depleted uranium hexafluoride (UF 6 ) stored in approximately 50,000 carbon steel cylinders. The cylinders are located at three DOE sites: the East Tennessee Technology Park (ETTP) site in Oak Ridge, Tennessee; the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The System Requirements Document (SRD) (LMES 1997a) delineates the requirements of the project, and the actions needed to fulfill these requirements are specified in the System Engineering Management Plan (SEMP) (LMES 1997b). This report documents activities that in whole or part satisfy specific requirements and actions stated in the UF 6 Cylinder Project SRD and SEMP with respect to forecasting cylinder conditions. The results presented here supercede those presented by Lyon (1995, 1996, 1997, 1998, 2000), and Schmoyer and Lyon (2001). Many of the wall thickness projections made in this report are conservative, because they are based on the assumption that corrosion trends will continue, despite activities such as improved monitoring, relocations to better storage, painting, and other improvements in storage conditions relative to the conditions at the times most of the wall thickness measurements were made. For thin-wall cylinders (design nominal wall thickness 312.5 mils), the critical minimum wall thicknesses criteria used in this report are 0 (breach), 62.5 mils, and 250 mils (1 mil = 0.001 in.). For thick-wall cylinders (design nominal wall thickness 625 mils), the thickness criteria used in this report are 0, 62.5 mils, and 500 mils. The criteria triples are preliminary boundaries identified within the project that indicate (1) loss of material (UF 6 ), (2) safe handling and stacking operations, and (3) standards for off-site transport and contents transfer criteria, respectively

Revised RCRA closure plan for the Interim Drum Yard (S-030) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Smith, C.M.

1994-09-01

The Interim Drum Yard (IDY) facility is a containerized waste storage area located in the Y-12 exclusion area. It was used to store waste materials which are regulated by RCRA (Resource Conservation and Recovery Act); uranyl nitrate solutions were also stored there. The closure plan outlines the actions required to achieve closure of IDY and is being submitted in accordance with TN Rule 1200-1-11.05(7) and 40 CFR 265.110

Beneficial reuse of empty DUF{sub 6} cylinders

Energy Technology Data Exchange (ETDEWEB)

Nieves, L.A.; Arnish, J.; Nabelssi, B. [Argonne National Lab., IL (United States)

1997-02-01

This paper discusses options for the disposal of depleted UF{sub 6} storage cylinders as they are freed over the next 20 years. Presently there are 46,000 mild steel cylinders in use, and projections show 600,000 tons of steel being freed over 20 years. The paper discusses the results of studies which have looked at various aspects of this issue: health risks; environmental impacts; costs and hassles; impact of DOE metal recycle policy. The general conclusions were that chemical and trauma risks dominate the risk evaluations, that risk levels are broadly speaking level for the studied disposition options, that environmental risks are highest for burial, and lowest for free release, while costs are higher for burial and recycling, than for reuse or free release.

Flow around a cylinder surrounded by a permeable cylinder in shallow water

Energy Technology Data Exchange (ETDEWEB)

Ozkan, Gokturk M.; Akilli, Huseyin; Sahin, Besir [Cukurova University, Department of Mechanical Engineering, Faculty of Engineering and Architecture, Adana (Turkey); Oruc, Vedat [Dicle University, Department of Mechanical Engineering, Diyarbakir (Turkey)

2012-12-15

The change in flow characteristics downstream of a circular cylinder (inner cylinder) surrounded by an outer permeable cylinder was investigated in shallow water using particle image velocimetry technique. The diameter of the inner cylinder and the water height were kept constant during the experiments as d=50 mm and h{sub w}=25 mm, respectively. The depth-averaged free-stream velocity was also kept constant as U=170 mm/s which corresponded to a Reynolds number of Re{sub d}=8,500 based on the inner cylinder diameter. In order to examine the effect of diameter and porosity of the outer cylinder on flow characteristics of the inner cylinder, five different outer cylinder diameters (D=60, 70, 80, 90 and 100 mm) and four different porosities ({beta}=0.4, 0.5, 0.6 and 0.7) were used. It was shown that both porosity and outer cylinder diameter had a substantial effect on the flow characteristics downstream of the circular cylinder. Turbulent statistics clearly demonstrated that in comparison with the bare cylinder (natural case), turbulent kinetic energy and Reynolds stresses decreased remarkably when an outer cylinder was placed around the inner cylinder. Thereby, the interaction of shear layers of the inner cylinder has been successfully prevented by the presence of outer cylinder. It was suggested by referring to the results that the outer cylinder having 1.6{<=}D/d{<=}2.0 and 0.4{<=}D/d{<=}0.6 should be preferred to have a better flow control in the near wake since the peak magnitude of turbulent kinetic energy was considerably low in comparison with the natural case and it was nearly constant for these mentioned porosities {beta}, and outer cylinder to inner cylinder diameter ratios D/d. (orig.)

Aspects of uranium chemistry pertaining to UF{sub 6} cylinder handling

Energy Technology Data Exchange (ETDEWEB)

Ritter, R.L.; Barber, E.J. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31

Under normal conditions, the bulk of UF{sub 6} in storage cylinders will be in the solid state with an overpressure of gaseous UF{sub 6} well below one atmosphere. Corrosion of the interior of the cylinder will be very slow, with formation of a small amount of reduced fluoride, probably U{sub 2}F{sub 9}. The UO{sub 3}-HF-H{sub 2}O phase diagram indicates that reaction of any inleaking water vapor with the solid UF{sub 6} will generate the solid material [H{sub 3}O]{sub 2}(U(OH){sub 4}F{sub 4}) in equilibrium with an aqueous HF solution containing only small amounts of uranium. The corrosion of the steel cylinder by these materials may be enhanced over that observed with gaseous anhydrous UF{sub 6}.

Work accidents during cable yarding operations in Central Europe 2006 – 2014

International Nuclear Information System (INIS)

Allman, M.; Jankovský, M.; Allmanová, Z.; Ferenčík, M.; Messingerová, V.; Vlčková, M.; Stanimir Stoilov

2017-01-01

Aim of study: This study is focused on detailed analysis of accidents in yarding during the years 2006–2014. There is still not enough information about such accidents in Central Europe in the literature available. Area of study: We collected the data on occupational accidents recorded in timber yarding from the databases of the Slovak state forest enterprise. Material and Methods: The data on occupational accidents were recorded according to actual European Regulation, the form of the record meets the requirements of the ESAW (European Statistics on Accidents at Work) methodology. To analyze the data, we used the multiple regression and correlation analysis, contingency tables, and a χ2 –test. Main results: Almost half of the accidents were the foot injuries and the most frequent type of injury was fracture of a bone. The most hazardous operation was yarding. Most of the accidents occurred between 1301-1400 h (22 %). The most frequent agent causing accidents were Particles, dust, splinters, fragments, etc. (14.05 by ESAW). Research highlights: This study informs about the most important risk factors in timber yarding, the most hazardous parts of shift, as well as the days when the most accidents occur during the week, and as such contributes to better understanding of how the accidents happen in timber yarding. The information can be subsequently used in knowledge-based improvement of safety trainings in forest enterprises.

Work accidents during cable yarding operations in Central Europe 2006 – 2014

Energy Technology Data Exchange (ETDEWEB)

Allman, M.; Jankovský, M.; Allmanová, Z.; Ferenčík, M.; Messingerová, V.; Vlčková, M.; Stanimir Stoilov

2017-11-01

Aim of study: This study is focused on detailed analysis of accidents in yarding during the years 2006–2014. There is still not enough information about such accidents in Central Europe in the literature available. Area of study: We collected the data on occupational accidents recorded in timber yarding from the databases of the Slovak state forest enterprise. Material and Methods: The data on occupational accidents were recorded according to actual European Regulation, the form of the record meets the requirements of the ESAW (European Statistics on Accidents at Work) methodology. To analyze the data, we used the multiple regression and correlation analysis, contingency tables, and a χ2 –test. Main results: Almost half of the accidents were the foot injuries and the most frequent type of injury was fracture of a bone. The most hazardous operation was yarding. Most of the accidents occurred between 1301-1400 h (22 %). The most frequent agent causing accidents were Particles, dust, splinters, fragments, etc. (14.05 by ESAW). Research highlights: This study informs about the most important risk factors in timber yarding, the most hazardous parts of shift, as well as the days when the most accidents occur during the week, and as such contributes to better understanding of how the accidents happen in timber yarding. The information can be subsequently used in knowledge-based improvement of safety trainings in forest enterprises.

Vorticity generation and wake transition for a translating circular cylinder: Wall proximity and rotation effects

DEFF Research Database (Denmark)

Hourigan, K.; Rao, A.; Brøns, Morten

2013-01-01

The wake transitions of generic bluff bodies, such as a circular cylinder, near a wall are important because they provide understanding of different transition paths towards turbulence, and give some insight into the effect of surface modifications on the flow past larger downstream structures......-annihilate with opposite-signed vorticity, and can be stored at a free surface, thus conserving the total vorticity, or circulation. Vorticity generation, diffusion and storage are demonstrated for a cylinder translating and rotating near a wall. The wake characteristics and the wake transitions are shown to change...... dramatically under the influence of cylinder rotation and wall proximity. At gaps between the cylinder and the wall of less than approximately 0.25 cylinder diameter, the wake becomes three dimensional prior to becoming unsteady, while for larger gaps the initial transition is to an unsteady two...

Production rates and costs of cable yarding wood residue from clearcut units

Science.gov (United States)

Chris B. LeDoux

1984-01-01

Wood residue is a little used source of fiber, chips, and fuel because harvest costs are largely unknown. This study calculates incremental production rates and costs for yarding and loading logging residue in clearcut old-growth Douglas-fir/western hemlock forests. Harvest operations were observed for two timber sales in western Oregon. Three different cable yarding...

Macro-Encapsulated PCM Cylinder Module Based on Paraffin and Float Stones

Directory of Open Access Journals (Sweden)

Kailiang Huang

2016-05-01

Full Text Available Organic phase change material (PCM with macro-encapsulation is attractive in energy storage applications as it has relatively low cost. This study focuses on using PET plastic pipes to encapsulate paraffin and using low-cost float stones to increase the thermal conductivity of PCM modules as they have a special structure of high porosity. Float stones were immersed in the liquid PCM and an ultrasonic welding method used to prevent leakage of the PET plastic pipes. Scanning electron microscopy (SEM was used to discover the appearance of the composite PCM. The thermal performance of the PCM cylinder module was analyzed through experimental tests of a constant-temperature water bath and numerical simulations. The result indicates that this PCM Ccylinder module is superior in thermal energy storage compared with the reference module even though fewer PCM was contained and the latent heat loss is considerable. The pipe diameter is an important parameter when using this kind of PCM cylinder module in water tanks.

Oxygen Cylinders: “life” or “death”? | Gupta | African Health Sciences

African Journals Online (AJOL)

Oxygen is crucial to maintain and save human life. Other than medical purposes it is widely used for manufacture of mineral water, fabrication works and other industrial activities. If adequate precautionary measures are not adopted while handling, storage or transport of oxygen cylinder or container, accidental blast may ...

Effect of farm yard manure and nitrogen application on seed cotton yield under arid climatic conditions

International Nuclear Information System (INIS)

Anwar, M.M.

2005-01-01

The importance of farm yard manure and green manuring is well established for better crop production. The availability of farm yard manure is becoming difficult due to mechanized farming. An experiment was conducted with farm yard manure application in less quantity i.e. 5000 kg per hectare through fermenter with irrigation water as concentrated solution of farm yard manure. Four levels of nitrogen i.e. 0, 50, 100 and 150 kg/ha were applied through soil to Cotton crop planted on bed-furrows. Two years average results indicated that application of FYM at the rate of 5 metric ton per hectare through fermenter with 0, 50, 100 and 150 kgN/ha through soil increased seed cotton by 7 percent, on over all average basis of all fertilizer levels, as compared with no farm yard manure application. There was 6 percent increase with first 50 kgN/ha in the presence of FYM where as 100 kgN/ha gave 15% increase in seed cotton yield over no nitrogen application. It indicated that the efficiency of nitrogen at the rate of 100 kg/ha in the presence of farm yard manure was increased. There was 7, 15 and 20 percent increase in seed cotton with 50, 100 and 150 kgN/ha over no nitrogen on over all average basis of farm yard manure variables. Benefit cost ratio was more with FYM application alone.(author)

19th century London dust-yards: A case study in closed-loop resource efficiency

International Nuclear Information System (INIS)

Velis, Costas A.; Wilson, David C.; Cheeseman, Christopher R.

2009-01-01

The material recovery methods used by dust-yards in early 19th century London, England and the conditions that led to their development, success and decline are reported. The overall system developed in response to the market value of constituents of municipal waste, and particularly the high coal ash content of household 'dust'. The emergence of lucrative markets for 'soil' and 'breeze' products encouraged dust-contractors to recover effectively 100% of the residual wastes remaining after readily saleable items and materials had been removed by the thriving informal sector. Contracting dust collection to the private sector allowed parishes to keep the streets relatively clean, without the need to develop institutional capacity, and for a period this also generated useful income. The dust-yard system is, therefore, an early example of organised, municipal-wide solid waste management, and also of public-private sector participation. The dust-yard system had been working successfully for more than 50 years before the Public Health Acts of 1848 and 1875, and was thus important in facilitating a relatively smooth transition to an institutionalised, municipally-run solid waste management system in England. The dust-yards can be seen as early precursors of modern materials recycling facilities (MRFs) and mechanical-biological treatment (MBT) plants; however, it must be emphasised that dust-yards operated without any of the environmental and occupational health considerations that are indispensable today. In addition, there are analogies between dust-yards and informal sector recycling systems currently operating in many developing countries

Effect of the waste products storage on the environmental pollution by toxic organic compounds

Directory of Open Access Journals (Sweden)

Aleksandra Lewkiewicz-Małysa

2005-11-01

Full Text Available A permanent deposition of industrial wastes is a method of its neutralization. A storage yard for toxic materials must meet specific site and construction conditions. The storage place region of toxic organic waste materials has to be monitored. The environmental impact of this waste on the groundwater quality, especially the migration of persistent organic pollutants, was discussed on the example of a chemical plant.

Plant species richness and abundance in residential yards across a tropical watershed: implications for urban sustainability

Directory of Open Access Journals (Sweden)

Cristina P. Vila-Ruiz

2014-09-01

Full Text Available Green spaces within residential areas provide important contributions to the sustainability of urban systems. Therefore, studying the characteristics of these areas has become a research priority in cities worldwide. This project evaluated various aspects of the plant biodiversity of residential yards (i.e., front yards and back yards within the Río Piedras watershed in the San Juan metropolitan area of Puerto Rico. Our work included gathering information on vegetation composition and abundance of woody species (i.e., trees, shrubs, palms, ferns and large herbs (>2 m height, species origin (native vs. introduced, and species uses (ornamental, food, and medicinal plants. A total of 424 yards were surveyed within an area of 187,191 m². We found 383 woody species, with shrubs being the most abundant plant habitat. As expected, residential yards hosted a disproportionate amount of introduced species (69.5%. The most common shrub species were all non-native ornamentals, whereas the most common tree species included food trees as well as ornamental plants and two native species. Front yards hosted more ornamental species per unit area than backyards, while the latter had more food plants. The high amount of introduced species may present a challenge in terms of implementation of plant conservation initiatives if there is no clear definition of urban conservation goals. On the other hand, the high frequency of yards containing food plants may facilitate the development of residential initiatives that could provide future adaptive capacity to food shortages.

Optimising the Slab Yard Planning and Crane Scheduling Problem using a two-stage heuristic

DEFF Research Database (Denmark)

Hansen, Anders Dohn; Clausen, Jens

2010-01-01

In this paper, we present the Slab Yard Planning and Crane Scheduling Problem. The problem has its origin in steel production facilities with a large throughput. A slab yard is used as a buffer for slabs that are needed in the upcoming production. Slabs are transported by cranes and the problem...

Variation in training regimens in professional showjumping yards

NARCIS (Netherlands)

Lönnell, A C; Bröjer, J; Nostell, K; Hernlund, E; Roepstorff, L; Tranquille, C A; Murray, R C; Oomen, A; van Weeren, René; Bitschnau, C; Montavon, S; Weishaupt, M A; Egenvall, A

2014-01-01

REASONS FOR PERFORMING STUDY: Training regimens of showjumping horses under field conditions are largely undocumented. OBJECTIVES: The aims of this study were to quantify and compare training regimens used in professional-level showjumping yards, with respect to time exercised and type of activity.

The Present Status of Using Natural Gas Cylinders and Acoustic Emission in Thailand

Science.gov (United States)

Jomdecha, C.; Jirarungsatian, C.; Methong, W.; Poopat, B.

This chapter presents the status of using natural gas cylinders (CNG/NGV) and acoustic emission (AE) in Thailand. During the period from 2006 to 2013, more than 600,000 CNG cylinder units for vehicles were installed and used for transportation, cars, and trucks in Thailand. The number of cylinder units will be tentatively increased in the future due to the increase in gasoline price. Due to the use of high-pressurization equipment in public, the issue of a risk to public safety has been raised. As of this writing, in 2013, the testing standard from the Thai Department of Energy Business recommends inspection every 5 years using effective inspection methods in order to guarantee safe usage of gas cylinders, including the AE method, following ISO 16148. Normally in Thailand, AE is used in research and petrochemical plants as a special technique. The main applications are testing of pressure vessels, aboveground storage tanks, and university research. Few companies are available to conduct AE for testing natural gas cylinders due to the limited safety of the high-pressure operation and AE equipment and a lack of qualified AE personnel. To develop AE techniques, equipment, procedures, and acceptance criteria of natural gas cylinders are the main focus of AE personnel in Thailand. A desired achievement for current development is for natural gas cylinder testing, which can be applied in field tests and supported by a national testing standard.

Engine Cylinder Temperature Control

Science.gov (United States)

Kilkenny, Jonathan Patrick; Duffy, Kevin Patrick

2005-09-27

A method and apparatus for controlling a temperature in a combustion cylinder in an internal combustion engine. The cylinder is fluidly connected to an intake manifold and an exhaust manifold. The method and apparatus includes increasing a back pressure associated with the exhaust manifold to a level sufficient to maintain a desired quantity of residual exhaust gas in the cylinder, and varying operation of an intake valve located between the intake manifold and the cylinder to an open duration sufficient to maintain a desired quantity of fresh air from the intake manifold to the cylinder, wherein controlling the quantities of residual exhaust gas and fresh air are performed to maintain the temperature in the cylinder at a desired level.

Delamination of Composite Cylinders

Science.gov (United States)

Davies, Peter; Carlsson, Leif A.

The delamination resistance of filament wound glass/epoxy cylinders has been characterized for a range of winding angles and fracture mode ratios using beam fracture specimens. The results reveal that the delamination fracture resistance increases with increasing winding angle and mode II (shear) fraction (GΠ/G). It was also found that interlaced fiber bundles in the filament wound cylinder wall acted as effective crack arresters in mode I loading. To examine the sensitivity of delamina-tion damage on the strength of the cylinders, external pressure tests were performed on filament-wound glass/epoxy composite cylinders with artificial defects and impact damage. The results revealed that the cylinder strength was insensitive to the presence of single delaminations but impact damage caused reductions in failure pressure. The insensitivity of the failure pressure to a single delamination is attributed to the absence of buckling of the delaminated sublaminates before the cylinder wall collapsed. The impacted cylinders contained multiple delaminations, which caused local reduction in the compressive load capability and reduction in failure pressure. The response of glass/epoxy cylinders was compared to impacted carbon reinforced cylinders. Carbon/epoxy is more sensitive to damage but retains higher implosion resistance while carbon/PEEK shows the opposite trend.

Internal combustion engine cylinder-to-cylinder balancing with balanced air-fuel ratios

Science.gov (United States)

Harris, Ralph E.; Bourn, Gary D.; Smalley, Anthony J.

2006-01-03

A method of balancing combustion among cylinders of an internal combustion engine. For each cylinder, a normalized peak firing pressure is calculated as the ratio of its peak firing pressure to its combustion pressure. Each cylinder's normalized peak firing pressure is compared to a target value for normalized peak firing pressure. The fuel flow is adjusted to any cylinder whose normalized peak firing pressure is not substantially equal to the target value.

Methods and results for stress analyses on 14-ton, thin-wall depleted UF6 cylinders

International Nuclear Information System (INIS)

Kirkpatrick, J.R.; Chung, C.K.; Frazier, J.L.; Kelley, D.K.

1996-10-01

Uranium enrichment operations at the three US gaseous diffusion plants produce depleted uranium hexafluoride (DUF 6 ) as a residential product. At the present time, the inventory of DUF 6 in this country is more than half a million tons. The inventory of DUF 6 is contained in metal storage cylinders, most of which are located at the gaseous diffusion plants. The principal objective of the project is to ensure the integrity of the cylinders to prevent causing an environmental hazard by releasing the contents of the cylinders into the atmosphere. Another objective is to maintain the cylinders in such a manner that the DUF 6 may eventually be converted to a less hazardous material for final disposition. An important task in the DUF 6 cylinders management project is determining how much corrosion of the walls can be tolerated before the cylinders are in danger of being damaged during routine handling and shipping operations. Another task is determining how to handle cylinders that have already been damaged in a manner that will minimize the chance that a breach will occur or that the size of an existing breach will be significantly increased. A number of finite element stress analysis (FESA) calculations have been done to analyze the stresses for three conditions: (1) while the cylinder is being lifted, (2) when a cylinder is resting on two cylinders under it in the customary two-tier stacking array, and (3) when a cylinder is resting on tis chocks on the ground. Various documents describe some of the results and discuss some of the methods whereby they have been obtained. The objective of the present report is to document as many of the FESA cases done at Oak Ridge for 14-ton thin-wall cylinders as possible, giving results and a description of the calculations in some detail

40 CFR 60.1445 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

Science.gov (United States)

2010-07-01

... curtain incinerators that burn 100 percent yard waste? 60.1445 Section 60.1445 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1445 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If your air curtain incinerator combusts...

Comparison of planted soil infiltration systems for treatment of log yard runoff.

Science.gov (United States)

Hedmark, Asa; Scholz, Miklas; Aronsson, Par; Elowson, Torbjorn

2010-07-01

Treatment of log yard runoff is required to avoid contamination of receiving watercourses. The research aim was to assess if infiltration of log yard runoff through planted soil systems is successful and if different plant species affect the treatment performance at a field-scale experimental site in Sweden (2005 to 2007). Contaminated runoff from the log yard of a sawmill was infiltrated through soil planted with Alnus glutinosa (L.) Gärtner (common alder), Salix schwerinii X viminalis (willow variety "Gudrun"), Lolium perenne (L.) (rye grass), and Phalaris arundinacea (L.) (reed canary grass). The study concluded that there were no treatment differences when comparing the four different plants with each other, and there also were no differences between the tree and the grass species. Furthermore, the infiltration treatment was effective in reducing total organic carbon (55%) and total phosphorus (45%) concentrations in the runoff, even when the loads on the infiltration system increased from year to year.

Treatment of log yard run-off by irrigation of grass and willows

International Nuclear Information System (INIS)

Jonsson, Maria; Dimitriou, Ioannis; Aronsson, Paer; Elowson, Torbjoern

2006-01-01

Log yard run-off is a potential environmental risk, among other things because it creates an oxygen deficiency in receiving watercourses. This study was conducted to investigate the purification efficiency of soil-plant systems with couchgrass (Elymus repens) and willows (Salix sp.) when intensively irrigated with run-off from an open sprinkling system at a Norway spruce (Picea abies) log yard. The purification efficiency was determined both at the field scale (couchgrass) and in 68-L lysimeters (couchgrass and willows). Groundwater in the field and drainage water from the lysimeters were analysed for Total Organic Carbon (TOC), distillable phenols, total P, and total N. Retention of TOC, phenols and P occurred but no difference between couchgrass and willows was observed. The system had better purification capacity at the field scale than in the lysimeters. -- By irrigating willow and couchgrass soil-plant systems with log yard run-off water, TOC, phenols, and phosphorus were reduced with 35% to 96% in the water

Economic analysis of using above ground gas storage devices for compressed air energy storage system

Science.gov (United States)

Liu, Jinchao; Zhang, Xinjing; Xu, Yujie; Chen, Zongyan; Chen, Haisheng; Tan, Chunqing

2014-12-01

Above ground gas storage devices for compressed air energy storage (CAES) have three types: air storage tanks, gas cylinders, and gas storage pipelines. A cost model of these gas storage devices is established on the basis of whole life cycle cost (LCC) analysis. The optimum parameters of the three types are determined by calculating the theoretical metallic raw material consumption of these three devices and considering the difficulties in manufacture and the influence of gas storage device number. The LCCs of the three types are comprehensively analyzed and compared. The result reveal that the cost of the gas storage pipeline type is lower than that of the other two types. This study may serve as a reference for designing large-scale CAES systems.

Morphological characteristic of purple long yard bean cultivars and their tolerance to drought stress

Directory of Open Access Journals (Sweden)

M W Lestari

2015-01-01

Full Text Available The cultivation of purple long yard bean which tolerance to drought stress and have high productivity can improve farming in arid area. The purpose of this study was to evaluate the mechanism of the tolerance purple long yard beans to drought stress based on morphologic characters, to get the hypothesis method of tolerance and to obtain tolerance cultivars to the drought stress. Eight cultivars of purple long yard beans, i.e. UBPHU1-41, UBPHU1-130, UBPU3-153, UBPU1-202, UBPU2-222, UBPU1-365, Brawijaya 4 and Bagong 2, were tested in two environmental conditions, 100% field capacity and 50% field capacity. The results showed that drought stress in purple long yard bean affected all morphological characters observed, except for root length and flowering time. Estimation of tolerance to drought stress using the Principles Component Analysis (PCA showed that the shoot fresh weight could be an indicator of purple pod bean tolerance to drought stress. However, the test using Stress Susceptibility Index (SSI was not able to classify the purple long yard bean tolerance to drought stress. The results of analysis using PCA followed by discriminant analysis and clustering dendrogram showed that the UBPU1-41, UBPU1-130, UBPU2-222, UBPU1-365, UB4 and Bagong 2 cultivars were medium cultivars that are tolerant to drought stress. Therefore, they can be planted in semiarid regions.

40 CFR 62.15375 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

Science.gov (United States)

2010-07-01

... curtain incinerators that burn 100 percent yard waste? 62.15375 Section 62.15375 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15375 What are the emission limits for air curtain incinerators that burn 100 percent yard...

40 CFR 62.15380 - How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste?

Science.gov (United States)

2010-07-01

... curtain incinerators that burn 100 percent yard waste? 62.15380 Section 62.15380 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15380 How must I monitor opacity for air curtain incinerators that burn 100 percent yard...

40 CFR 60.1920 - What are the emission limits for air curtain incinerators that burn 100 percent yard waste?

Science.gov (United States)

2010-07-01

... curtain incinerators that burn 100 percent yard waste? 60.1920 Section 60.1920 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1920 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If...

Investigating transportation system in container terminals and developing a yard crane scheduling model

Directory of Open Access Journals (Sweden)

Hassan Javanshir

2012-01-01

Full Text Available The world trade has tremendous growth in marine transportation. This paper studies yard crane scheduling problem between different blocks in container terminal. Its purpose is to minimize total travel time of cranes between blocks and total delayed workload in blocks at different periods. In this way the problem is formulated as a mixed integer programming (MIP model. The block pairs between which yard cranes will be transferred, during the various periods, is determined by this model. Afterwards the model is coded in LINGO software, which benefits from branch and bound algorithm to solve. Computational results determine the yard cranes movement sequence among blocks to achieve minimum total travel time for cranes and minimum total delayed workload in blocks at different planning periods. Also the results show capability and adequacy of the developed model.

Experiments with HEU (93.14 wt.%) metal annuli with internal graphite cylinder

Energy Technology Data Exchange (ETDEWEB)

Liu, Xiaobo [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bess, John D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Wehmann, Udo [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mihalczo, John T. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-04-01

A variety of critical experiments were constructed of enriched uranium metal (oralloy ) during the 1960s and 1970s at the Oak Ridge Critical Experiments Facility (ORCEF) in support of criticality safety operations at the Y-12 Plant. The purposes of these experiments included the evaluation of storage, casting, and handling limits for the Y-12 Plant and providing data for verification of calculation methods and cross-sections for nuclear criticality safety applications. These included solid cylinders of various diameters, annuli of various inner and outer diameters, two and three interacting cylinders of various diameters, and graphite and polyethylene reflected cylinders and annuli. Of the hundreds of delayed critical experiments, only three experimental configurations are described here. They are internal graphite reflected metal uranium assemblies with three different diameter HEU annuli (15-9 inches, 15-7 inches and 13-7 inches). These experiments can be found in Reference 1 and in their associated logbook

40 CFR 60.1450 - How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste?

Science.gov (United States)

2010-07-01

... curtain incinerators that burn 100 percent yard waste? 60.1450 Section 60.1450 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1450 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use EPA Reference Method 9 in appendix A of...

40 CFR 60.1925 - How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste?

Science.gov (United States)

2010-07-01

... curtain incinerators that burn 100 percent yard waste? 60.1925 Section 60.1925 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1925 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use...

Characterization of stormwater at selected South Carolina Department of Transportation maintenance yards and section shed facilities in Ballentine, Conway, and North Charleston, South Carolina, 2010-12

Science.gov (United States)

Journey, Celeste A.; Conlon, Kevin J.

2014-01-01

Increased impervious surfaces (driveways, parking lots, and buildings) and human activities (residential, industrial, and commercial) have been linked to substantial changes in both the quality and quantity of stormwater on a watershed scale (Brabec and others, 2002; Pitt and Maestre, 2005). Small-scale storage and equipment repair facilities increase impervious surfaces that prevent infiltration of stormwater, and these facilities accommodate activities that can introduce trace metals, organic compounds, and other contaminants to the facility’s grounds. Thus, these small facilities may contribute pollutants to the environment during storm events (U.S. Environmental Protection Agency, 1992). The South Carolina Department of Transportation (SCDOT) operates section shed and maintenance yard facilities throughout the State. Prior to this investigation, the SCDOT had no data to define the quality of stormwater leaving these facilities. To provide these data, the U.S. Geological Survey (USGS), in cooperation with the SCDOT, conducted an investigation to identify and quantify constituents that are transported in stormwater from two maintenance yards and a section shed in three different areas of South Carolina. The two maintenance yards, in North Charleston and Conway, S.C., were selected because they represent facilities where equipment and road maintenance materials are stored and complete equipment repair operations are conducted. The section shed, in Ballentine, S.C., was selected because it is a facility that stores equipment and road maintenance material. Characterization of the constituents that were transported in stormwater from these representative SCDOT maintenance facilities may be used by the SCDOT in the development of stormwater management plans for similar section shed and maintenance yard facilities throughout the State to improve stormwater quality.

Atlanta Rail Yard Study: Evaluation of local-scale air pollution trends using stationary and mobile monitoring

Science.gov (United States)

Intermodal rail yards are important nodes in the freight transportation network, where freight is organized and moved from one mode of transport to another, critical equipment is serviced, and freight is routed to its next destination. Rail yard environments are also areas with ...

Spent nuclear fuel assembly storage vessel

International Nuclear Information System (INIS)

Yagishita, Takuya

1998-01-01

The vessel of the present invention promotes an effect of removing after heat of spent nuclear fuel assemblies so as not to give force to the storage vessel caused by expansion of heat removing partitioning plates. Namely, the vessel of the present invention comprises a cylinder body having closed upper and lower portions and a plurality of heat removing partitioning cylinders disposed each at a predetermined interval in the circumferential direction of the above-mentioned cylinder body. The heat removing partitioning cylinders comprises (1) first heat removing partitioning plates extended in the radial direction of the cylinder body and opposed at a predetermined gap in the circumferential direction of the cylinder body, and having the base ends on the side of the inner wall of the cylinder body being secured to the inner wall of the cylinder body and (2) a second heat removing plate for connecting the top ends of both opposed heat removing partitioning plates on the central side of the cylinder body with each other. Spent nuclear fuel assemblies are contained in a plurality of closed spaces surrounded by the first heat removing partitioning plates and the second heat removing partitioning plate. With such constitution, since after heat is partially transferred from the heat removing partitioning plates to the cylindrical body directly by heat conduction, the heat removing effect can be promoted compared with the prior art. (I.S.)

78 FR 20169 - Notice of Availability of an Environmental Assessment for the Proposed Hudson Yards Concrete...

Science.gov (United States)

2013-04-03

... Environmental Assessment for the Proposed Hudson Yards Concrete Casing Project in New York, New York AGENCY... of Availability of Environmental Assessment for the Hudson Yards Concrete Casing Construction... the construction of an underground concrete casing to preserve a right-of- way (ROW) (the proposed...

Residents' Yard Choices and Rationales in a Desert City: Social Priorities, Ecological Impacts, and Decision Tradeoffs

Science.gov (United States)

Larson, Kelli L.; Casagrande, David; Harlan, Sharon L.; Yabiku, Scott T.

2009-11-01

As a dominant land use in urban ecosystems, residential yards impact water and other environmental resources. Converting thirsty lawns into alternative landscapes is one approach to water conservation, yet barriers such as cultural norms reinforce the traditional lawn. Meanwhile, the complex social and ecological implications of yard choices complicate programs aimed at changing grass and other yard features for particular purposes. In order to better understand individual landscape decisions, we qualitatively examined residents’ rationales for their preferred yard types in the desert metropolis of Phoenix, Arizona. After briefly presenting landscape choices across two survey samples, the dominant reasons for preferences are discussed: appearance, maintenance, environment, recreation, microclimate, familiarity, and health/safety. Three broader analytical themes emerged from these descriptive codes: (1) residents’ desires for attractive, comfortable landscapes of leisure encompassing pluralistic tastes, lifestyles, and perceptions; (2) the association of environmental benefits and impacts with different landscape types involving complex social and ecological tradeoffs; and (3) the cultural legacies evident in modern landscape choices, especially in terms of a dichotomous human-nature worldview among long-time residents of the Phoenix oasis. Given these findings, programs aimed at landscape change must recognize diverse preferences and rationalization processes, along with the perceived versus actual impacts and tradeoffs of varying yard alternatives.

Discrete event simulation model for external yard choice of import container terminal in a port buffer area

Science.gov (United States)

Rusgiyarto, Ferry; Sjafruddin, Ade; Frazila, Russ Bona; Suprayogi

2017-06-01

Increasing container traffic and land acquisition problem for terminal expansion leads to usage of external yard in a port buffer area. This condition influenced the terminal performance because a road which connects the terminal and the external yard was also used by non-container traffic. Location choice problem considered to solve this condition, but the previous research has not taken account a stochastic condition of container arrival rate and service time yet. Bi-level programming framework was used to find optimum location configuration. In the lower-level, there was a problem to construct the equation, which correlated the terminal operation and the road due to different time cycle equilibrium. Container moves from the quay to a terminal gate in a daily unit of time, meanwhile, it moves from the terminal gate to the external yard through the road in a minute unit of time. If the equation formulated in hourly unit equilibrium, it cannot catch up the container movement characteristics in the terminal. Meanwhile, if the equation formulated in daily unit equilibrium, it cannot catch up the road traffic movement characteristics in the road. This problem can be addressed using simulation model. Discrete Event Simulation Model was used to simulate import container flow processes in the container terminal and external yard. Optimum location configuration in the upper-level was the combinatorial problem, which was solved by Full Enumeration approach. The objective function of the external yard location model was to minimize user transport cost (or time) and to maximize operator benefit. Numerical experiment was run for the scenario assumption of two container handling ways, three external yards, and thirty-day simulation periods. Jakarta International Container Terminal (JICT) container characteristics data was referred for the simulation. Based on five runs which were 5, 10, 15, 20, and 30 repetitions, operation one of three available external yards (external yard

Gas Cylinder Safety, Course 9518

Energy Technology Data Exchange (ETDEWEB)

Glass, George [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-10-27

This course, Gas Cylinder Safety (#9518), presents an overview of the hazards and controls associated with handling, storing, using, and transporting gas cylinders. Standard components and markings of gas cylinders are also presented, as well as the process for the procurement, delivery, and return of gas cylinders at Los Alamos National Laboratory (LANL).

A study on Maruca vitrata infestation of Yard-long beans (Vigna unguiculata subspecies sesquipedalis

Directory of Open Access Journals (Sweden)

R.C. Jayasinghe

2015-09-01

Full Text Available Globally, Maruca vitrata (Geyer is a serious yield constraint on food legumes including Yard-long bean (Vigna unguiculata subspecies sesquipedalis. However, there is a dearth of information on its damage potential, distribution and population dynamics in Yard-long beans. In the present study, the level of M. vitrata larval infestation on flowers and pods of Yard-long beans in Sri Lanka was determined with respect to three consecutive cropping seasons, Yala, Off and Maha. Results indicated that larval infestation and abundance varied with developmental stage of flowers and pods, cropping season and their combined interactive effects. Flowers of Yard-long beans were more prone to M. vitrata larval attack compared to pods. Abundance and level of infestation of M. vitrata varied with plant parts, having a ranking of flower buds (highest > open flowers > mature pods > immature pods (lowest. Peak infestation was observed six and eight weeks after planting on flowers and pods, respectively. Among the three cropping seasons, M. vitrata infestation was found to be higher during Maha and Off seasons compared to Yala. The findings of this study contribute to the identified knowledge gap regarding the field biology of an acknowledged important pest, M. vitrata, in a previously understudied crop in Sri Lanka.

Fiber Tracking Cylinder Nesting

International Nuclear Information System (INIS)

Stredde, H.

1999-01-01

The fiber tracker consists of 8 concentric carbon fiber cylinders of varying diameters, from 399mm to 1032.2mm and two different lengths. 1.66 and 2.52 meters. Each completed cylinder is covered over the entire o.d. with scintillating fiber ribbons with a connector on each ribbon. These ribbons are axial (parallel to the beam line) at one end and stereo (at 3 deg. to the beam line) at the other. The ribbon connectors have dowel pins which are used to match with the connectors on the wave guide ribbons. These dowel pins are also used during the nesting operation, locating and positioning measurements. The nesting operation is the insertion of one cylinder into another, aligning them with one another and fastening them together into a homogeneous assembly. For ease of assembly. the nesting operation is accomplished working from largest diameter to smallest. Although the completed assembly of all 8 cylinders glued and bolted together is very stiff. individual cylinders are relatively flexible. Therefore. during this operation, No.8 must be supported in a manner which maintains its integrity and yet allows the insertion of No.7. This is accomplished by essentially building a set of dummy end plates which replicate a No.9 cylinder. These end plates are mounted on a wheeled cart that becomes the nesting cart. Provisions for a protective cover fastened to these rings has been made and will be incorporated in finished product. These covers can be easily removed for access to No.8 and/or the connection of No.8 to No.9. Another wheeled cart, transfer cart, is used to push a completed cylinder into the cylinder(s) already mounted in the nesting cart.

How to Park Freight Trains on Rail-Rail Transshipment Yards: The Train Location Problem

OpenAIRE

Michael Kellner; Nils Boysen; Malte Fliedner

2010-01-01

In modern rail-rail transshipment yards huge gantry cranes spanning all railway tracks allow for an efficent transshipment of containers between different freight trains. This way, multiple trains loaded with cargo for varying destinations can be consolidated to a reduced number of homogeneous trains, which is an essential requirement of hub-and-spoke railway systems. An important problem during the daily operations of such a transshipment yard is the train location problem, which assigns eac...

Antennas on circular cylinders

DEFF Research Database (Denmark)

Knudsen, H. L.

1959-01-01

On the basis of the results obtained by Silver and Saunders [4] for the field radiated from an arbitrary slot in a perfectly conducting circular cylinder, expressions have been derived for the field radiated by a narrow helical slot, with an arbitrary aperture field distribution, in a circular...... antenna in a circular cylinder. By a procedure similar to the one used by Silver and Saunders, expressions have been derived for the field radiated from an arbitrary surface current distribution on a cylinder surface coaxial with a perfectly conducting cylinder. The cases where the space between the two...

Wake flow behaviour behind a smaller cylinder oscillating in the wake of an upstream stationary cylinder

Energy Technology Data Exchange (ETDEWEB)

Gao, Yangyang; Sun, Zhilin [Ocean College, Zhejiang University, Hangzhou 310058 (China); Tan, Danielle S [Maritime Research Centre, Nanyang Technological University, Singapore 639798 (Singapore); Yu, Dingyong [College of Engineering, Ocean University of China, 266100 (China); Tan, Soon Keat, E-mail: yygao@zju.edu.cn [Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 639798 (Singapore)

2014-04-01

The flow patterns around a cylinder oscillating freely in the wake of a larger cylinder upstream were investigated using the particle image velocimetry technique. The upstream cylinder was fixed at both ends while the downstream smaller cylinder was held by springs such that it was free to oscillate in the transverse direction. The flow patterns, amplitudes of oscillation and vortex shedding frequencies were compared with those of a single cylinder. In the presence of the upstream cylinder, the three parameters characterizing the oscillation response of the smaller cylinder—amplitude of oscillation, vortex shedding frequency and Reynolds stresses—were greatly reduced. While their magnitude increased with gap ratio, these three parameters were still smaller than the corresponding magnitudes for a single oscillating cylinder. The peak values of turbulence statistics such as Reynolds shear stress and normal stress behind the oscillating downstream cylinder were similarly reduced, and increased with gap ratios. (paper)

Passive heat transfer augmentation in a cylindrical annulus utilizing multiple perturbations on the inner and outer cylinders

International Nuclear Information System (INIS)

Iyer, S.V.; Vafai, K.

1999-01-01

The study of natural convection flow and heat transfer within a cylindrical annulus has received considerable attention because of its numerous applications, such as in nuclear reactor design, electronic component cooling, thermal storage systems, energy conservation, energy storage, and energy transmission. Here, the effects of multiple geometric perturbations on the inner and outer cylinders of an annulus with impermeable end walls are investigated in this work. A three-dimensional study was done using a numerical scheme based on a Galerkin method of finite element formulation. The nature of the buoyancy-induced flow field has been analyzed in detail. The flow fields for the cases considered were found to be qualitatively similar, and the introduction of each additional perturbation altered the flow field in a regular and recurring manner. The introduction of each perturbation on the outer cylinder causes clockwise and counterclock-wise rotating patterns on either side of the perturbation in the upper circumferential regions of the annulus. The motion of the fluid entrained by these circulatory patterns constitutes the key features of the flow pattern observed in the annulus. It is observed that the presence of multiple perturbations on the inner and outer cylinders substantially increases the overall heat transfer rate as compared to the regular annulus without any perturbation. Key qualitative and quantitative effects of the introduction of perturbations on both the inner and outer cylinders of the annulus are discussed

Technical Safety Requirements for the Waste Storage Facilities

International Nuclear Information System (INIS)

Laycak, D.T.

2010-01-01

This document contains Technical Safety Requirements (TSR) for the Radioactive and Hazardous Waste Management (RHWM) WASTE STORAGE FACILITIES, which include Area 625 (A625) and the Decontamination and Waste Treatment Facility (DWTF) Storage Area at Lawrence Livermore National Laboratory (LLNL). The TSRs constitute requirements regarding the safe operation of the WASTE STORAGE FACILITIES. These TSRs are derived from the Documented Safety Analysis for the Waste Storage Facilities (DSA) (LLNL 2009). The analysis presented therein determined that the WASTE STORAGE FACILITIES are low-chemical hazard, Hazard Category 2 non-reactor nuclear facilities. The TSRs consist primarily of inventory limits and controls to preserve the underlying assumptions in the hazard and accident analyses. Further, appropriate commitments to safety programs are presented in the administrative controls sections of the TSRs. The WASTE STORAGE FACILITIES are used by RHWM to handle and store hazardous waste, TRANSURANIC (TRU) WASTE, LOW-LEVEL WASTE (LLW), mixed waste, California combined waste, nonhazardous industrial waste, and conditionally accepted waste generated at LLNL as well as small amounts from other U.S. Department of Energy (DOE) facilities, as described in the DSA. In addition, several minor treatments (e.g., size reduction and decontamination) are carried out in these facilities. The WASTE STORAGE FACILITIES are located in two portions of the LLNL main site. A625 is located in the southeast quadrant of LLNL. The A625 fenceline is approximately 225 m west of Greenville Road. The DWTF Storage Area, which includes Building 693 (B693), Building 696 Radioactive Waste Storage Area (B696R), and associated yard areas and storage areas within the yard, is located in the northeast quadrant of LLNL in the DWTF complex. The DWTF Storage Area fenceline is approximately 90 m west of Greenville Road. A625 and the DWTF Storage Area are subdivided into various facilities and storage areas, consisting

Technical Safety Requirements for the Waste Storage Facilities

Energy Technology Data Exchange (ETDEWEB)

Laycak, D T

2008-06-16

This document contains Technical Safety Requirements (TSR) for the Radioactive and Hazardous Waste Management (RHWM) WASTE STORAGE FACILITIES, which include Area 625 (A625) and the Decontamination and Waste Treatment Facility (DWTF) Storage Area at Lawrence Livermore National Laboratory (LLNL). The TSRs constitute requirements regarding the safe operation of the WASTE STORAGE FACILITIES. These TSRs are derived from the 'Documented Safety Analysis for the Waste Storage Facilities' (DSA) (LLNL 2008). The analysis presented therein determined that the WASTE STORAGE FACILITIES are low-chemical hazard, Hazard Category 2 non-reactor nuclear facilities. The TSRs consist primarily of inventory limits and controls to preserve the underlying assumptions in the hazard and accident analyses. Further, appropriate commitments to safety programs are presented in the administrative controls sections of the TSRs. The WASTE STORAGE FACILITIES are used by RHWM to handle and store hazardous waste, TRANSURANIC (TRU) WASTE, LOW-LEVEL WASTE (LLW), mixed waste, California combined waste, nonhazardous industrial waste, and conditionally accepted waste generated at LLNL as well as small amounts from other U.S. Department of Energy (DOE) facilities, as described in the DSA. In addition, several minor treatments (e.g., size reduction and decontamination) are carried out in these facilities. The WASTE STORAGE FACILITIES are located in two portions of the LLNL main site. A625 is located in the southeast quadrant of LLNL. The A625 fenceline is approximately 225 m west of Greenville Road. The DWTF Storage Area, which includes Building 693 (B693), Building 696 Radioactive Waste Storage Area (B696R), and associated yard areas and storage areas within the yard, is located in the northeast quadrant of LLNL in the DWTF complex. The DWTF Storage Area fenceline is approximately 90 m west of Greenville Road. A625 and the DWTF Storage Area are subdivided into various facilities and storage areas

Heat transfers through diesel-engine cylinder liners

Energy Technology Data Exchange (ETDEWEB)

Green, R T; Jambunathan, K; Probert, S D

1983-01-01

A computer package has been developed, using a finite-element technique, to predict the steady-state rate of heat transfer radially through the cylinder liner, or other axisymmetric components, of a medium-speed diesel engine. Comparisons between experimentally measured and computer predicted results have been made: better corroboration occurs for engine loads above 1034 k N m/sup -2/ BMEP. The predictive computer package DIESHT needs only a simple 'user input' and produces a complete graphical output of generated mesh and computed isotherms. Computational storage requirements are modest so that the program can be used with a CAD system, if required, in order to facilitate an interactive design procedure.

Analyzing the Efficiency of a Start-Up Cable Yarding Crew in Southern China under New Forest Management Perspectives

Directory of Open Access Journals (Sweden)

Stephan Hoffmann

2016-08-01

Full Text Available This case study analyzed the performance of a start-up cable yarding crew in southern China through operational monitoring by consecutive time studies, long-term log book recordings and efficiency evaluation by stochastic frontier analysis (SFA. The crew, which used a KOLLER K303 H mobile tower yarder, was monitored for two years. During this period, detailed data recordings of 687 yarding cycles of 12 yarding corridors as well as log book recordings of an additional 1122 scheduled system hours (SSH, including all delays were generated. Mean extraction productivity of the system ranged between 5.23 and 6.40 m3 per productive system hour (PSH0, excluding all delays, mostly depending on slope yarding distance and lateral distance. Corresponding gross-productivity ranged from 1.91 to 2.24 m3/SSH, with an overall mean machine utilization rate of 31%. Unproductive yarding times and delays associated with the relative low utilization rate were mainly caused by lengthy rigging processes, as well as organizational deficiencies and not yet fully developed skill sets of the operating crew. The latter was reflected in a mean efficiency effect frontier value of 0.62 based on evaluation of data sets of individual yarding cycles recorded during detailed assessments, suggesting a mean improvement potential of 38% based on the SFA, translating in a potentially achievable gross-productivity of 2.64 to 3.09 m3/SSH. We conclude that current local operating conditions including insufficient planning, implementation and logistics and in particular, frequent discontinuations of system operations of up to three months all resulting in generally low operation hours per shift and per year, inhibit efficient operations and rapid skill development. These circumstances also inhibit an economic utilization of the equipment. Nevertheless, from a technical perspective, yarding systems have a promising potential in southern China.

Effect of longitudinal and transverse vibrations of an upstream square cylinder on vortex shedding behind two inline square cylinders

International Nuclear Information System (INIS)

Patil, Pratish P; Tiwari, Shaligram

2009-01-01

The characteristics of unsteady wakes behind a stationary square cylinder and another upstream vibrating square cylinder have been investigated numerically with the help of a developed computational code. The effect of longitudinal as well as transverse vibrations of the upstream cylinder is studied on the coupled wake between the two cylinders, which is found to control the vortex shedding behavior behind the downstream stationary cylinder. Computations are carried out for a fixed value of Reynolds number (Re = 200) and three different values of excitation frequencies of the upstream cylinder, namely less than, equal to and greater than the natural frequency of vortex shedding corresponding to flow past a stationary square cylinder. The vortex shedding characteristics of the unsteady wakes behind the vibrating and stationary cylinders are found to differ significantly for longitudinal and transverse modes of vibration of the upstream cylinder. The wake of the downstream stationary cylinder is found to depict a synchronization behavior with the upstream cylinder vibration. The spacing between the two cylinders has been identified to be the key parameter influencing the synchronization phenomenon. The effect of cylinder spacing on the wake synchronization and the hydrodynamic forces has been examined. In addition, a comparison of the drag forces for flow past transversely vibrating square and circular cylinders for similar amplitudes and frequencies of cylinder vibration has been presented while employing the tested computational code.

Composting of food and yard wastes by locally isolated fungal strains

African Journals Online (AJOL)

GREGORY

2011-12-16

PC2094), Lentinus tigrinus. M609RQY, Aspergillus niger and Penicillium spp. were used as inocula in source separated organics. (food and yard trimmings) from solid waste (SW) to produce biofertilizer and stabilize waste.

Technical Safety Requirements for the Waste Storage Facilities

International Nuclear Information System (INIS)

Larson, H L

2007-01-01

This document contains Technical Safety Requirements (TSR) for the Radioactive and Hazardous Waste Management (RHWM) WASTE STORAGE FACILITIES, which include Area 612 (A612) and the Decontamination and Waste Treatment Facility (DWTF) Storage Area at Lawrence Livermore National Laboratory (LLNL). The TSRs constitute requirements regarding the safe operation of the WASTE STORAGE FACILITIES. These TSRs are derived from the Documented Safety Analysis for the Waste Storage Facilities (DSA) (LLNL 2006). The analysis presented therein determined that the WASTE STORAGE FACILITIES are low-chemical hazard, Hazard Category 2 non-reactor nuclear facilities. The TSRs consist primarily of inventory limits and controls to preserve the underlying assumptions in the hazard and accident analyses. Further, appropriate commitments to safety programs are presented in the administrative controls sections of the TSRs. The WASTE STORAGE FACILITIES are used by RHWM to handle and store hazardous waste, TRANSURANIC (TRU) WASTE, LOW-LEVEL WASTE (LLW), mixed waste, California combined waste, nonhazardous industrial waste, and conditionally accepted waste generated at LLNL as well as small amounts from other U.S. Department of Energy (DOE) facilities, as described in the DSA. In addition, several minor treatments (e.g., drum crushing, size reduction, and decontamination) are carried out in these facilities. The WASTE STORAGE FACILITIES are located in two portions of the LLNL main site. A612 is located in the southeast quadrant of LLNL. The A612 fenceline is approximately 220 m west of Greenville Road. The DWTF Storage Area, which includes Building 693 (B693), Building 696 Radioactive Waste Storage Area (B696R), and associated yard areas and storage areas within the yard, is located in the northeast quadrant of LLNL in the DWTF complex. The DWTF Storage Area fenceline is approximately 90 m west of Greenville Road. A612 and the DWTF Storage Area are subdivided into various facilities and storage

Technical Safety Requirements for the Waste Storage Facilities

Energy Technology Data Exchange (ETDEWEB)

Larson, H L

2007-09-07

This document contains Technical Safety Requirements (TSR) for the Radioactive and Hazardous Waste Management (RHWM) WASTE STORAGE FACILITIES, which include Area 612 (A612) and the Decontamination and Waste Treatment Facility (DWTF) Storage Area at Lawrence Livermore National Laboratory (LLNL). The TSRs constitute requirements regarding the safe operation of the WASTE STORAGE FACILITIES. These TSRs are derived from the Documented Safety Analysis for the Waste Storage Facilities (DSA) (LLNL 2006). The analysis presented therein determined that the WASTE STORAGE FACILITIES are low-chemical hazard, Hazard Category 2 non-reactor nuclear facilities. The TSRs consist primarily of inventory limits and controls to preserve the underlying assumptions in the hazard and accident analyses. Further, appropriate commitments to safety programs are presented in the administrative controls sections of the TSRs. The WASTE STORAGE FACILITIES are used by RHWM to handle and store hazardous waste, TRANSURANIC (TRU) WASTE, LOW-LEVEL WASTE (LLW), mixed waste, California combined waste, nonhazardous industrial waste, and conditionally accepted waste generated at LLNL as well as small amounts from other U.S. Department of Energy (DOE) facilities, as described in the DSA. In addition, several minor treatments (e.g., drum crushing, size reduction, and decontamination) are carried out in these facilities. The WASTE STORAGE FACILITIES are located in two portions of the LLNL main site. A612 is located in the southeast quadrant of LLNL. The A612 fenceline is approximately 220 m west of Greenville Road. The DWTF Storage Area, which includes Building 693 (B693), Building 696 Radioactive Waste Storage Area (B696R), and associated yard areas and storage areas within the yard, is located in the northeast quadrant of LLNL in the DWTF complex. The DWTF Storage Area fenceline is approximately 90 m west of Greenville Road. A612 and the DWTF Storage Area are subdivided into various facilities and storage

Dynamic Friction Performance of a Pneumatic Cylinder with Al2O3 Film on Cylinder Surface.

Science.gov (United States)

Chang, Ho; Lan, Chou-Wei; Wang, Hao-Xian

2015-11-01

A friction force system is proposed for accurately measuring friction force and motion properties produced by reciprocating motion of piston in a pneumatic cylinder. In this study, the proposed system is used to measure the effects of lubricating greases of different viscosities on the friction properties of pneumatic cylinder, and improvement of stick-slip motion for the cylinder bore by anodizing processes. A servo motor-driven ball screw is used to drive the pneumatic cylinder to be tested and to measure the change in friction force of the pneumatic cylinder. Experimental results show, that under similar test conditions, the lubricating grease with viscosity VG100 is best suited for measuring reciprocating motion of the piston of pneumatic cylinder. The wear experiment showed that, in the Al2O3 film obtained at a preset voltage 40 V in the anodic process, the friction coefficient and hardness decreased by 55% and increased by 274% respectively, thus achieving a good tribology and wear resistance. Additionally, the amplitude variation in the friction force of the pneumatic cylinder wall that received the anodizing treatment was substantially reduced. Additionally, the stick-slip motion of the pneumatic cylinder during low-speed motion was substantially improved.

48 CFR 52.247-66 - Returnable Cylinders.

Science.gov (United States)

2010-10-01

... Cylinders (MAY 1994) (a) Cylinder, referred to in this clause, is a pressure vessel designed for pressures... clause. (c) For each cylinder lost or damaged beyond repair while in the Government's possession, the... associated replacement values.] These cylinders shall become Government property. (d) If any lost cylinder is...

Using the adaptive SMA composite cylinder concept to reduce radial dilation in composite pressure vessels

Science.gov (United States)

Paine, Jeffrey S.; Rogers, Craig A.

1995-05-01

Composite materials are widely used in the design of pressurized gas and fluid vessels for applications ranging from underground gasoline storage tanks to rocket motors for the space shuttle. In the design of a high pressure composite vessel (Pi > 12 Ksi), thick-wall (R/h short term dilation and long term creep are not problematic for applications requiring only the containment of the pressurized fluid. In applications where metallic liners are required, however, substantial dilation and creep causes plastic yielding which leads to reduced fatigue life. To applications such as a hydraulic accumulator, where a piston is employed to fit and seal the fluid in the composite cylinder, the dilation and creep may allow leakage and pressure loss around the piston. A concept called the adaptive composite cylinder is experimentally presented. Shape memory alloy wire in epoxy resin is wrapped around or within polymer matrix composite cylinders to reduce radial dilation of the cylinder. Experimental results are presented that demonstrate the ability of the SMA wire layers to reduce radial dilation. Results from experimental testing of the recovery stress fatigue response of nitinol shape memory alloy wires is also presented.

Data acquisition and PV module power production in upgraded TEP/AzRISE solar test yard

Science.gov (United States)

Bennett, Whit E.; Fishgold, Asher D.; Lai, Teh; Potter, Barrett G.; Simmons-Potter, Kelly

2017-08-01

The Tucson Electric Power (TEP)/University of Arizona AzRISE (Arizona Research Institute for Solar Energy) solar test yard is continuing efforts to improve standardization and data acquisition reliability throughout the facility. Data reliability is ensured through temperature-insensitive data acquisition devices with battery backups in the upgraded test yard. Software improvements allow for real-time analysis of collected data, while uploading to a web server. Sample data illustrates high fidelity monitoring of the burn-in period of a polycrystalline silicon photovoltaic module test string with no data failures over 365 days of data collection. In addition to improved DAQ systems, precision temperature monitoring has been implemented so that PV module backside temperatures are routinely obtained. Weather station data acquired at the test yard provides local ambient temperature, humidity, wind speed, and irradiance measurements that have been utilized to enable characterization of PV module performance over an extended test period

Flow over an inline oscillating circular cylinder in the wake of a stationary circular cylinder

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yang; Zhu, Keqiang, E-mail: zhukeqiang@nbu.edu.cn [Faculty of Maritime and Transportation, Ningbo University, Ningbo 315211 (China)

2017-02-15

Flow interference between an upstream stationary cylinder and an inline oscillating cylinder is studied with the lattice Boltzmann method. With a fixed Reynolds number Re  = 100 and pitch ratio L / D  = 4, the effects of oscillation amplitude A / D  = [0.25, 1] and frequency f {sub e}/ f {sub s} = [0.5, 2] are investigated. The wake response state is categorized into lock-in and non-lock-in. The lock-in zone in the bifurcation diagram of amplitude versus frequency is discontinuous. Response states of upstream and downstream wakes are similar under the conditions of small amplitude or low frequency. However, with large oscillating parameters, the two wakes are prone to be in different states as the flow field becomes irregular. Two distinct flow regimes have been identified, i.e., single-cylinder and two-cylinder shedding regimes. The presence of single-cylinder shedding regime is attributed to the low shedding frequency of the downstream cylinder at large amplitude. Hydrodynamic forces of the oscillating tandem system are discussed. The results reveal that forces on the two cylinders behave differently and that the absence of vortices in the gap flow significantly reduces the forces exerting on the tandem system. (paper)

Composting of food and yard wastes by locally isolated fungal strains

African Journals Online (AJOL)

PC2094), Lentinus tigrinus M609RQY, Aspergillus niger and Penicillium spp. were used as inocula in source separated organics (food and yard trimmings) from solid waste (SW) to produce biofertilizer and stabilize waste constituents. The results ...

Monitoring Dangerous Goods in Container Yard Using the Internet of Things

Directory of Open Access Journals (Sweden)

Lianhong Ding

2016-01-01

Full Text Available The Internet of Things (IoT, a network of objects, has been regarded as the next revolution for the global information industry after the Internet. With IoT, many intelligent applications can be accomplished or improved. This paper presents a framework for dangerous goods management in container yard using IoT technology. The framework consists of three layers: perceptual layer, transport layer, and application layer. It offers an infrastructure for management and data analysis and utilization. According to the features of dangerous goods, the framework can be enhanced for container information forecast, container gate-in and gate-out management, environment parameters monitoring, and fire control as well. In order to verify our method, a prototype system is developed, which shows good performance. With our method, safe operation of dangerous goods in container yard can be accomplished.

Swap your propane cylinder with SWOP

International Nuclear Information System (INIS)

Anon.

1997-01-01

A very successful propane cylinder exchange program operated by South Western Ontario Propane (SWOP) Inc., was described. The company specializes in propane cylinder exchange and in the refurbishing and marketing of top quality domestic and commercial propane cylinders. The company, currently operating out of Bradford, Ontario, was started in 1991. It employs a staff of 25 in peak season. It has some 200 exchange outlets throughout Ontario and has accepted outdated tanks from as far west as Manitoba and as far east as Quebec. A typical transaction involves bringing an empty cylinder to the nearest SWOP location and exchanging it for a full SWOP cylinder. SWOP does about 50,000 to 60,000 exchanges a year. For the consumer, the program is said to be cheaper, safer and more convenient than getting refills. As far as dealers are concerned operating a SWOP exchange outlet can add extra profits, attract new customers, and build additional consumer loyalty without the need for extra staff or additional indoor space. SWOP delivers full cylinders to exchange outlets on a weekly basis when it also picks up the empty cylinders. At dealer locations, the cylinders (full or empty) are stored in company -designed vandal-proof metal cages. Major expansion of the network of outlets and the cylinder refurbishing and refilling facilities are planned for 1998

Thermalhydraulic analyses of AECL's spent fuel dry storage systems

International Nuclear Information System (INIS)

Moffett, R.; Sabourin, G.

1995-01-01

This paper presents the validation of one- and three-dimensional thermalhydraulic models to be used to evaluate the thermal performance of AECL's MACSTOR and CANSTOR spent fuel dry storage modules. For this purpose, we compared analytical results to results of experiments conducted at AECL's Whiteshell Laboratories where mockups of the MACSTOR module and of a CANDU fuel storage basket were tested. The paper shows improvements to a simple one-dimensional model of the MACSTOR mock-up used previously. The replacement of constant heat transfer coefficients by free convection correlations, the addition of a storage cylinder model, and the addition of a radiation heat transfer model improved the predictions of concrete and storage cylinder temperatures. The paper also presents a new three-dimensional model for flow and heat transfer in the MACSTOR mock-up developed using CFDS-FLOW3D and -RAD3D computer programs. CFDS-FLOW3D code can estimate loss coefficients in complex geometry to an accuracy better than standard engineering correlations. The flow and temperature fields predicted using CFDS-FLOW3D are consistent with the measurements made during MACSTOR mock-up experiments (author). 5 refs., 4 tabs., 9 figs

Fire testing of bare uranium hexafluoride cylinders

Energy Technology Data Exchange (ETDEWEB)

Pryor, W.A. [PAI Corp., Oak Rige, TN (United States)

1991-12-31

In 1965, the Oak Ridge Gaseous Diffusion Plant (ORGDP), now the K-25 Site, conducted a series of tests in which bare cylinders of uranium hexafluoride (UF{sub 6}) were exposed to engulfing oil fires for the US Atomic Energy Commission (AEC), now the US Department of Energy (DOE). The tests are described and the results, conclusions, and observations are presented. Two each of the following types of cylinders were tested: 3.5-in.-diam {times} 7.5-in.-long cylinders of Monel (Harshaw), 5.0-in.-diam {times} 30-in.-long cylinders of Monel, and 8-in.-diam {times} 48-in.-long cylinders of nickel. The cylinders were filled approximately to the standard UF{sub 6} fill limits of 5, 55, and 250 lb, respectively, with a U-235 content of 0.22%. The 5-in.- and 8-in.-diam cylinders were tested individually with and without their metal valve covers. For the 3.5-in.-diam Harshaw cylinders and the 5.0-in.-diam cylinder without a valve cover the valves failed and UF{sub 6} was released. The remaining cylinders ruptured explosively in time intervals ranging from about 8.5 to 11 min.

Fire testing of bare uranium hexafluoride cylinders

Energy Technology Data Exchange (ETDEWEB)

Pryor, W.A. [PAI Corp., Oak Ridge, TN (United States)

1991-12-31

In 1965, the Oak Ridge Gaseous Diffusion Plant (ORGDP), now the K-25 Site, conducted a series of tests in which bare cylinders of uranium hexafluoride (UF{sub 6}) were exposed to engulfing oil fires for the US Atomic Energy Commission (AEC), now the US Department of Energy (DOE). The tests are described and the results, conclusions, and observations are presented. Two each of the following types of cylinders were tested: 3.5-in.-diam {times} 7.5-in.-long cylinders of Monel (Harshaw), 5.0-in.-diam {times} x 30-in.-long cylinders of Monel, and 8-in.-diam {times} 48-in.-long cylinders of nickel. The cylinders were filled approximately to the standard UF{sub 6} fill limits of 5, 55, and 250 lb, respectively, with a U-235 content of 0.22%. The 5-in.- and 8-in.-diam cylinders were tested individually with and without their metal valve covers. For the 3.5-in.-diam Harshaw cylinders and the 5.0-in.-diam cylinder without a valve cover, the valves failed and UF{sub 6} was released. The remaining 6 cylinders ruptured explosively in time intervals ranging from about 8.5 to 11 min.

Exploring Homeowner Diffusion of Yard Care Knowledge as One Step Toward Improving Urban Ecosystems

Science.gov (United States)

Martini, Nicholas F.; Nelson, Kristen C.; Dahmus, Maria E.

2014-11-01

Urban ecosystems are increasingly influenced by residential yard care decisions. This had led researchers to focus on homeowner education programs when it comes to yard care. Typically, the success of programs designed to influence yard care is based on whether the target subject changes his or her behavior in a more environmentally conscious manner. This threshold, however, fails to consider if individuals share this information with their friends and neighbors, thus having a possible spillover effect. In this paper, we focus on the transmission of new lawn management information among neighbors and consider (1) if individuals discuss information they learned in a short-term educational program, (2) what factors are associated with diffusion, (3) what information individuals share, and (4) what barriers to transmission exist. In the Minneapolis-St. Paul metropolitan area, we used data from a mailed survey, group discussions, and mailed information exchanges. Results indicate that best management practices for yards can diffuse through the neighborhood (approximately 34 % shared information with their neighbors in a one-month period). In addition, factors such as (1) attending a group discussion, 2) individual social connectedness, (3) length of home ownership, and (4) the presence of children in the household were found to be positively related to increased sharing of information. Also, for lawns, the content of information shared tended to be about increasing grass height and reducing fertilizer applications. Finally, we find barriers to sharing ideas based on spatial, temporal, or perception factors but overcoming some of these barriers is possible.

Thermodynamic analysis of a thermal storage unit under the influence of nano-particles added to the phase change material and/or the working fluid

Science.gov (United States)

Abolghasemi, Mehran; Keshavarz, Ali; Mehrabian, Mozaffar Ali

2012-11-01

The thermal storage unit consists of two concentric cylinders where the working fluid flows through the internal cylinder and the annulus is filled with a phase change material. The system carries out a cyclic operation; each cycle consists of two processes. In the charging process the hot working fluid enters the internal cylinder and transfers heat to the phase change material. In the discharging process the cold working fluid enters the internal cylinder and absorbs heat from the phase change material. The differential equations governing the heat transfer between the two media are solved numerically. The numerical results are compared with the experimental results available in the literature. The performance of an energy storage unit is directly related to the thermal conductivity of nano-particles. The energy consumption of a residential unit whose energy is supplied by a thermal storage system can be reduced by 43 % when using nano-particles.

Flow past a rotating cylinder

Science.gov (United States)

Mittal, Sanjay; Kumar, Bhaskar

2003-02-01

Flow past a spinning circular cylinder placed in a uniform stream is investigated via two-dimensional computations. A stabilized finite element method is utilized to solve the incompressible Navier Stokes equations in the primitive variables formulation. The Reynolds number based on the cylinder diameter and free-stream speed of the flow is 200. The non-dimensional rotation rate, [alpha] (ratio of the surface speed and freestream speed), is varied between 0 and 5. The time integration of the flow equations is carried out for very large dimensionless time. Vortex shedding is observed for [alpha] cylinder. The results from the stability analysis for the rotating cylinder are in very good agreement with those from direct numerical simulations. For large rotation rates, very large lift coefficients can be obtained via the Magnus effect. However, the power requirement for rotating the cylinder increases rapidly with rotation rate.

Biochemical methane potential, biodegradability, alkali treatment and influence of chemical composition on methane yield of yard wastes.

Science.gov (United States)

Gunaseelan, Victor Nallathambi

2016-03-01

In this study, the biochemical CH4 potential, rate, biodegradability, NaOH treatment and the influence of chemical composition on CH4 yield of yard wastes generated from seven trees were examined. All the plant parts were sampled for their chemical composition and subjected to the biochemical CH4 potential assay. The component parts exhibited significant variation in biochemical CH4 potential, which was reflected in their ultimate CH4 yields that ranged from 109 to 382 ml g(-1) volatile solids added and their rate constants that ranged from 0.042 to 0.173 d(-1). The biodegradability of the yard wastes ranged from 0.26 to 0.86. Variation in the biochemical CH4 potential of the yard wastes could be attributed to variation in the chemical composition of the different fractions. In the Thespesia yellow withered leaf, Tamarindus fruit pericarp and Albizia pod husk, NaOH treatment enhanced the ultimate CH4 yields by 17%, 77% and 63%, respectively, and biodegradability by 15%, 77% and 61%, respectively, compared with the untreated samples. The effectiveness of NaOH treatment varied for different yard wastes, depending on the amounts of acid detergent fibre content. Gliricidia petals, Prosopis leaf, inflorescence and immature pod, Tamarindus seeds, Albizia seeds, Cassia seeds and Delonix seeds exhibited CH4 yields higher than 300 ml g(-1) volatile solids added. Multiple linear regression models for predicting the ultimate CH4 yield and biodegradability of yard wastes were designed from the results of this work. © The Author(s) 2016.

An Operator Perspective from a Facility Evaluation of an RFID-Based UF6 Cylinder Accounting and Tracking System

International Nuclear Information System (INIS)

Martyn, Rose; Fitzgerald, Peter; Stehle, Nicholas D.; Rowe, Nathan C.; Younkin, James R.

2011-01-01

An operational field test of a Radio-Frequency Identification (RFID) system for tracking and accounting UF6 cylinders was conducted at the Global Nuclear Fuel Americas (GNF) fuel fabrication plant in 2009. The Cylinder Accountability and Tracking System (CATS) was designed and deployed by Oak Ridge National Laboratory (ORNL) and evaluated in cooperation with GNF. The system required that passive RFID be attached to several UF6 30B cylinders as they were received at the site; then the cylinders were tracked as they proceeded to interim storage, to processing in an autoclave, and eventually to disposition from the site. This CATS deployment also provided a direct integration of scale data from the site accountability scales. The integration of this information into the tracking data provided an attribute for additional safeguards for evaluation. The field test provided insight into the advantages and challenges of using RFID at an operating nuclear facility. The RFID system allowed operators to interact with the technology and demonstrated the survivability of the tags and reader equipment in the process environment. This paper will provide the operator perspective on utilizing RFID technology for locating cylinders within the facility, thereby tracking the cylinders for process and for Material Control and Accounting functions. The paper also will present the operator viewpoint on RFID implemented as an independent safeguards system.

Global Trade, Local Impacts: Lessons from California on Health Impacts and Environmental Justice Concerns for Residents Living near Freight Rail Yards

Science.gov (United States)

Hricko, Andrea; Rowland, Glovioell; Eckel, Sandrah; Logan, Angelo; Taher, Maryam; Wilson, John

2014-01-01

Global trade has increased nearly 100-fold since 1950, according to the World Trade Organization. Today, major changes in trade are occurring with the advent of mega-ships that can transport thousands more containers than cargo ships now in use. Because global trade is expected to increase dramatically, the railroad industry—in the U.S. alone—has invested more than $5 billion a year over the past decade to expand rail yards and enhance rail routes to transport goods from ports to retail destinations. This article describes cancer risks for residents living in close proximity to rail yards with emissions of diesel particulate matter pollution from locomotives, trucks and yard equipment. The article examines the demographics (income, race/ethnicity) of populations living in the highest estimated cancer risk zones near 18 major rail yards in California, concluding that the majority are over-represented by either lower-income or minority residents (or both). The authors also describe a review of the news media and environmental impact reports to determine if rail yards are still being constructed or expanded in close proximity to homes and schools or in working class/working poor communities of color. The paper suggests policy efforts that might provide more public health protection and result in more “environmentally just” siting of rail yards. The authors conclude that diesel pollution from rail yards, which creates significant diesel cancer risks for those living near the facilities, is an often overlooked public health, health disparities and environmental justice issue in the U.S. The conclusions are relevant to other countries where international trade is increasing and large new intermodal rail facilities are being considered. PMID:24518649

Sub-wavelength resonances in polygonal metamaterial cylinders

DEFF Research Database (Denmark)

Arslanagic, Samel; Breinbjerg, Olav

2008-01-01

It has been shown that the sub-wavelength resonances of circular MTM cylinders also occur for polygonal MTM cylinders. This is the case for lossless and non-dispersive cylinders as well as lossy and dispersive cylinders. The sub-wavelength resonances are thus not limited to structures of canonical...

Treatment and storage of hydrogen isotopes

International Nuclear Information System (INIS)

Jung, H. S.; Lee, H. S.; An, D. H.; Kim, K. R.; Lee, S. H.; Choi, H. J.; Back, S. W.; Kang, H. S.; Eom, K. Y.; Lee, M. S.

2000-01-01

Storage of gaseous hydrogen isotopes in a cylinder is a well-established technology. However, Immobilization in the solid form is preferred for long-term storage of radioactive isotope gas because of the concern for leakage of the gas. The experimental thermodynamic p-c-T data show that Ti and U soak up hydrogen isotope gas at a temperature of a few hundred .deg. C and modest pressures. It was found that more hydrogen is dissolved in the metal than deuterium at constant pressure. Thus, the lighter isotope tends to be enriched in the solid phase

Approximation by Cylinder Surfaces

DEFF Research Database (Denmark)

Randrup, Thomas

1997-01-01

We present a new method for approximation of a given surface by a cylinder surface. It is a constructive geometric method, leading to a monorail representation of the cylinder surface. By use of a weighted Gaussian image of the given surface, we determine a projection plane. In the orthogonal...

Thermalhydraulic analyses of AECL`s spent fuel dry storage systems

Energy Technology Data Exchange (ETDEWEB)

Moffett, R; Sabourin, G [Atomic Energy of Canada Ltd., Montreal, PQ (Canada). CANDU Operations; Banas, A O [Atomic Energy of Canada Ltd., Chalk River, ON (Canada)

1996-12-31

This paper presents the validation of one- and three-dimensional thermalhydraulic models to be used to evaluate the thermal performance of AECL`s MACSTOR and CANSTOR spent fuel dry storage modules. For this purpose, we compared analytical results to results of experiments conducted at AECL`s Whiteshell Laboratories where mockups of the MACSTOR module and of a CANDU fuel storage basket were tested. The paper shows improvements to a simple one-dimensional model of the MACSTOR mock-up used previously. The replacement of constant heat transfer coefficients by free convection correlations, the addition of a storage cylinder model, and the addition of a radiation heat transfer model improved the predictions of concrete and storage cylinder temperatures. The paper also presents a new three-dimensional model for flow and heat transfer in the MACSTOR mock-up developed using CFDS-FLOW3D and -RAD3D computer programs. CFDS-FLOW3D code can estimate loss coefficients in complex geometry to an accuracy better than standard engineering correlations. The flow and temperature fields predicted using CFDS-FLOW3D are consistent with the measurements made during MACSTOR mock-up experiments (author). 5 refs., 4 tabs., 9 figs.

Theoretical and experimental stress analyses of ORNL thin-shell cylinder-to-cylinder model 2

International Nuclear Information System (INIS)

Gwaltney, R.C.; Bolt, S.E.; Bryson, J.W.

1975-10-01

Model 2 in a series of four thin-shell cylinder-to-cylinder models was tested, and the experimentally determined elastic stress distributions were compared with theoretical predictions obtained from a thin-shell finite-element analysis. Both the cylinder and the nozzle of model 2 had outside diameters of 10 in., giving a d 0 /D 0 ratio of 1.0, and both had outside diameter/thickness ratios of 100. Sixteen separate loading cases in which one end of the cylinder was rigidly held were analyzed. An internal pressure loading, three mutually perpendicular force components, and three mutually perpendicular moment components were individually applied at the free end of the cylinder and at the end of the nozzle. In addition to these 13 loadings, 3 additional loads were applied to the nozzle (in-plane bending moment, out-of-plane bending moment, and axial force) with the free end of the cylinder restrained. The experimental stress distributions for each of the 16 loadings were obtained using 152 three-gage strain rosettes located on the inner and outer surfaces. All the 16 loading cases were also analyzed theoretically using a finite-element shell analysis. The analysis used flat-plate elements and considered five degrees of freedom per node in the final assembled equations. The comparisons between theory and experiment show reasonably good general agreement, and it is felt that the analysis would be satisfactory for most engineering purposes. (auth)

Eratosthenes' teachings with a globe in a school yard

International Nuclear Information System (INIS)

Božić, Mirjana; Ducloy, Martial

2008-01-01

A globe, in a school or university yard, which simulates the Earth's orientation in space, could be a very useful and helpful device for teaching physics, geometry, astronomy and the history of science. It would be very useful for science education to utilize the forthcoming International Year of the Planet Earth 2008 and the International Year of Astronomy 2009 by installing globes in many school and university courtyards

Technical Report: Optimizing the Slab Yard Planning and Crane Scheduling Problem using a Two-Stage Approach

DEFF Research Database (Denmark)

Hansen, Anders Dohn; Clausen, Jens

2008-01-01

In this paper, we present The Slab Yard Planning and Crane Scheduling Problem. The problem has its origin in steel production facilities with a large throughput. A slab yard is used as a buffer for slabs that are needed in the upcoming production. Slabs are transported by cranes and the problem...... considered here, is concerned with the generation of schedules for these. The problem is decomposed and modeled in two parts, namely a planning problem and a scheduling problem. In the planning problem a set of crane operations is created to take the yard from its current state to a desired goal state...... schedule for the cranes is generated, where each operation is assigned to a crane and is given a specific time of initiation. For both models, a thorough description of the modeling details is given along with a specification of objective criteria. Variants of the models are presented as well. Preliminary...

Pressure cylinders under fire condition

Directory of Open Access Journals (Sweden)

Jan Hora

2016-03-01

Full Text Available The presence of pressure cylinders under fire conditions significantly increases the risk rate for the intervening persons. It is considerably problematic to predict the pressure cylinders behaviour during heat exposition, its destruction progress and possible following explosion of the produced air–gas mixture because pressure cylinders and its environment generate a highly complicated dynamic system during an uncontrolled destruction. The large scale tests carried out by the Pilsen Fire and Rescue Department and the Rapid Response Unit of the Czech Republic Police in October 2012 and in May 2014 in the Military area Brdy and in the area of the former Lachema factory in Kaznějov had several objectives, namely, to record, qualify and quantify some of the aspects of an uncontrolled heat destruction procedure of an exposed pressure cylinder in an enclosed space and to qualify and describe the process of a controlled destruction of a pressure cylinder by shooting through it including basic tactical concepts. The article describes the experiments that were carried out.

Access to Science and Literacy through Inquiry and School Yard Habitats

Science.gov (United States)

Cox-Petersen, Anne; Spencer, Brenda

2006-01-01

In this article, the authors describe an integrated science and literacy instructional model in which students build background knowledge by engaging in free-choice learning options during an investigation of school yard habitats. Students interact with their peers while inquiring, discussing findings, and using print resources to enhance learning.

Multiple Cylinder Free-Piston Stirling Machinery

Science.gov (United States)

Berchowitz, David M.; Kwon, Yong-Rak

In order to improve the specific power of piston-cylinder type machinery, there is a point in capacity or power where an advantage accrues with increasing number of piston-cylinder assemblies. In the case of Stirling machinery where primary energy is transferred across the casing wall of the machine, this consideration is even more important. This is due primarily to the difference in scaling of basic power and the required heat transfer. Heat transfer is found to be progressively limited as the size of the machine increases. Multiple cylinder machines tend to preserve the surface area to volume ratio at more favorable levels. In addition, the spring effect of the working gas in the so-called alpha configuration is often sufficient to provide a high frequency resonance point that improves the specific power. There are a number of possible multiple cylinder configurations. The simplest is an opposed pair of piston-displacer machines (beta configuration). A three-cylinder machine requires stepped pistons to obtain proper volume phase relationships. Four to six cylinder configurations are also possible. A small demonstrator inline four cylinder alpha machine has been built to demonstrate both cooling operation and power generation. Data from this machine verifies theoretical expectations and is used to extrapolate the performance of future machines. Vibration levels are discussed and it is argued that some multiple cylinder machines have no linear component to the casing vibration but may have a nutating couple. Example applications are discussed ranging from general purpose coolers, computer cooling, exhaust heat power extraction and some high power engines.

Natural convective heat transfer from square cylinder

Energy Technology Data Exchange (ETDEWEB)

Novomestský, Marcel, E-mail: marcel.novomestsky@fstroj.uniza.sk; Smatanová, Helena, E-mail: helena.smatanova@fstroj.uniza.sk; Kapjor, Andrej, E-mail: andrej.kapjor@fstroj.uniza.sk [University of Žilina, Faculty of Mechanical Engineering, Department of Power Engineering, Univerzitná 1, 010 26 Žilina (Slovakia)

2016-06-30

This article is concerned with natural convective heat transfer from square cylinder mounted on a plane adiabatic base, the cylinders having an exposed cylinder surface according to different horizontal angle. The cylinder receives heat from a radiating heater which results in a buoyant flow. There are many industrial applications, including refrigeration, ventilation and the cooling of electrical components, for which the present study may be applicable.

Radiation levels on empty cylinders containing heel material

Energy Technology Data Exchange (ETDEWEB)

Shockley, C.W. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

Empty UF{sub 6} cylinders containing heel material were found to emit radiation levels in excess of 200 mr/hr, the maximum amount stated in ORO-651. The radiation levels were as high as 335 mr/hr for thick wall (48X and 48Y) cylinders and 1050 mr/hr for thin wall (48G and 48H) cylinders. The high readings were found only on the bottom of the cylinders. These radiation levels exceeded the maximum levels established in DOT 49 CFR, Part 173.441 for shipment of cylinders. Holding periods of four weeks for thick-wall cylinders and ten weeks for thin-wall cylinders were established to allow the radiation levels to decay prior to shipment.

Composting of food and yard wastes by locally isolated fungal strains

African Journals Online (AJOL)

GREGORY

2011-12-16

Dec 16, 2011 ... 74% total organic matter (TOM), 7.2 pH and 132% germination index (GI) further showed the potentials of the produced compost. Based on this, food waste (FW) and yard trimmings (YT) showed an economic potential for sustainable production of compost using low technology. Key words: Lignocellulolytic ...

Atlanta Rail Yard Study (ARYS): Evaluation of local-scale air pollution trends and emissions quantification using stationary and mobile monitoring strategies

Science.gov (United States)

Intermodal rail yards are important nodes in the freight transportation network, where freight is organized and moved from one mode of transport to another, critical equipment is serviced, and freight is routed to its next destination. Rail yard environments are also areas with ...

Stress analysis of cylinder to cylinder intersections

International Nuclear Information System (INIS)

Revesz, Z.

1983-01-01

Cylinder to cylinder intersections have numerous applications in the power industry from different piping junctions to pressure vessel nozzles. A specific purpose computer program has been installed at the author's establishment for finite element analysis of such geometries. Some of the experiences are presented giving a short overview of the analysis of unreinforced man-holes, demonstrating how a more economical design has been verified by analysis. The program installed has linear-elastic and elasto-plastic capabilities. Further, it is prepared for heat transfer analysis with subsequent thermal stress computation. An efficient pre- and post-processor has also been installed and enhanced by the author. The software used is at its present stage capable for problem definition with input data such as outside/ inside diameters, length and number of subdivisions. Similarly simple is the load definition and the graphic representation of the full output. (author)

75 FR 72952 - Safety Zone; 1000-yard radius from position 29°48.77′ N 091°33.02′ W, Charenton Drainage and...

Science.gov (United States)

2010-11-29

...-AA00 Safety Zone; 1000-yard radius from position 29[deg]48.77' N 091[deg]33.02' W, Charenton Drainage.... SUMMARY: The Coast Guard is establishing a temporary safety zone extending to a 1000-yard radius from... Navigation and Drainage Canal will be closed to all marine traffic within a 1000-yard radius of position 29...

Stabilization of flow past a rounded cylinder

Science.gov (United States)

Samtaney, Ravi; Zhang, Wei

2016-11-01

We perform global linear stability analysis on low-Re flow past a rounded cylinder. The cylinder corners are rounded with a radius R, normalized as R+ = R / D where D is the cylinder diameter, and its effect on the flow stability characteristics is investigated. We compute the critical Reynolds number (Recr) for the onset of first instability, and quantify the perturbation growth rate for the super-critical flows. It is found that the flow can be stabilized by partially rounding the cylinder. Compared with the square and circular cylinders, the partially rounded cylinder has a higher Recr , attaining a maximum at around R+ = 0 . 30 , and the perturbation growth rate of the super-critical flows is reduced for Re R+ -> 0 . 00), while only the near-wake backflow is crucial for circular-like cylinders (R+ -> 0 . 50). The stability analysis results are also verified with those of the direct simulations and very good agreement is achieved. Supported by the KAUST Office of Competitive Research Funds under Award No. URF/1/1394-01. The supercomputer Shaheen at KAUST was utilized for the simulations.

Overseas shipments of 48Y cylinders

Energy Technology Data Exchange (ETDEWEB)

Tanaka, R.T.; Furlan, A.S. [Cameco Corp., Port Hope, Ontario (Canada)

1991-12-31

This paper describes experiences with two incidents of overseas shipments of uranium hexafluoride (UF{sub 6}) cylinders. The first incident involved nine empty UF{sub 6} cylinders in enclosed sea containers. Three UF{sub 6} cylinders broke free from their tie-downs and damaged and contaminated several sea containers. This paper describes briefly how decontamination was carried out. The second incident involved a shipment of 14 full UF{sub 6} cylinders. Although the incident did not cause an accident, the potential hazard was significant. The investigation of the cause of the near accident is recounted. Recommendations to alleviate future similar incidents for both cases are presented.

Natural convection heat transfer for a staggered array of heated, horizontal cylinders within a rectangular enclosure

Energy Technology Data Exchange (ETDEWEB)

Triplett, C.E.

1996-12-01

This thesis presents the results of an experimental investigation of natural convection heat transfer in a staggered array of heated cylinders, oriented horizontally within a rectangular enclosure. The main purpose of this research was to extend the knowledge of heat transfer within enclosed bundles of spent nuclear fuel rods sealed within a shipping or storage container. This research extends Canaan`s investigation of an aligned array of heated cylinders that thermally simulated a boiling water reactor (BWR) spent fuel assembly sealed within a shipping or storage cask. The results are presented in terms of piecewise Nusselt-Rayleigh number correlations of the form Nu = C(Ra){sup n}, where C and n are constants. Correlations are presented both for individual rods within the array and for the array as a whole. The correlations are based only on the convective component of the heat transfer. The radiative component was calculated with a finite-element code that used measured surface temperatures, rod array geometry, and measured surface emissivities as inputs. The correlation results are compared to Canaan`s aligned array results and to other studies of natural convection in horizontal tube arrays.

Natural convection heat transfer for a staggered array of heated, horizontal cylinders within a rectangular enclosure

International Nuclear Information System (INIS)

Triplett, C.E.

1996-12-01

This thesis presents the results of an experimental investigation of natural convection heat transfer in a staggered array of heated cylinders, oriented horizontally within a rectangular enclosure. The main purpose of this research was to extend the knowledge of heat transfer within enclosed bundles of spent nuclear fuel rods sealed within a shipping or storage container. This research extends Canaan's investigation of an aligned array of heated cylinders that thermally simulated a boiling water reactor (BWR) spent fuel assembly sealed within a shipping or storage cask. The results are presented in terms of piecewise Nusselt-Rayleigh number correlations of the form Nu = C(Ra) n , where C and n are constants. Correlations are presented both for individual rods within the array and for the array as a whole. The correlations are based only on the convective component of the heat transfer. The radiative component was calculated with a finite-element code that used measured surface temperatures, rod array geometry, and measured surface emissivities as inputs. The correlation results are compared to Canaan's aligned array results and to other studies of natural convection in horizontal tube arrays

Conceptual design and cost estimation of dry cask storage facility for spent fuel

International Nuclear Information System (INIS)

Maki, Yasuro; Hironaga, Michihiko; Kitano, Koichi; Shidahara, Isao; Shiomi, Satoshi; Ohnuma, Hiroshi; Saegusa, Toshiari

1985-01-01

In order to propose an optimum storage method of spent fuel, studies on the technical and economical evaluation of various storage methods have been carried out. This report is one of the results of the study and deals with storage facility of dry cask storage. The basic condition of this work conforms to ''Basic Condition for Spent Fuel Storage'' prepared by Project Group of Spent Fuel Dry Storage at July 1984. Concerning the structural system of cask storage facilities, trench structure system and concrete silo system are selected for storage at reactor (AR), and a reinforced concrete structure of simple design and a structure with membrance roof are selected for away from reactor (AFR) storage. The basic thinking of this selection are (1) cask is put charge of safety against to radioactivity and (2) storage facility is simplified. Conceptual designs are made for the selected storage facilities according to the basic condition. Attached facilities of storage yard structure (these are cask handling facility, cask supervising facility, cask maintenance facility, radioactivity control facility, damaged fuel inspection and repack facility, waste management facility) are also designed. Cost estimation of cask storage facility are made on the basis of the conceptual design. (author)

A methodology to identify the intake charge cylinder-to-cylinder distribution in turbocharged direct injection Diesel engines

Science.gov (United States)

Luján, José M.; Galindo, José; Serrano, José R.; Pla, Benjamín

2008-06-01

Exhaust gas recirculation (EGR) is currently the most important NOx emission control system. During the last few years the EGR rate has increased progressively as pollutant emission regulations have become more restrictive. High EGR rate levels have given the effect of the unsuitable EGR and air distribution between cylinders away, which causes undesirable engine behavior. In this sense, the study of the EGR distribution between cylinders achieves high importance. However, despite the fact that the EGR is continuously under study, not many studies have been undertaken to approach its distribution between cylinders. In concordance with the aspects outlined before, the aim of this paper is to propose a methodology that permits us to identify the EGR cylinder-to-cylinder dispersion in a commercial engine. In order to achieve this objective, experimental tests have been combined with both one-dimensional and three-dimensional fluid dynamic models.

Robust cylinder pressure estimation in heavy-duty diesel engines

NARCIS (Netherlands)

Kulah, S.; Forrai, A.; Rentmeester, F.; Donkers, T.; Willems, F.P.T.

2017-01-01

The robustness of a new single-cylinder pressure sensor concept is experimentally demonstrated on a six-cylinder heavy-duty diesel engine. Using a single-cylinder pressure sensor and a crank angle sensor, this single-cylinder pressure sensor concept estimates the in-cylinder pressure traces in the

Improvement of the Magnetic Shielding Effects by the Superposition of a Multi-Layered Ferromagnetic Cylinder over an HTS Cylinder: Relationship Between the Shielding Effects and the Layer Number of the Ferromagnetic Cylinder

International Nuclear Information System (INIS)

Yasui, K; Tarui, Y; Itoh, M

2006-01-01

The idealized magnetic shielded vessel can be realized by making use of a high-critical temperature superconductor (HTS). It is difficult for practical applications, however, to fabricate a shielding vessel that has a high value of the maximum shielded magnetic flux density B s0 . The present authors have improved the value of B s0 for the Bi-Pb-Sr-Ca-Cu-O (BPSCCO) cylinder used as the shielding vessel, by the superposition of a four-layered softiron cylinder over the BPSCCO cylinder, termed the four-layered superimposed cylinder. The B s4 value of 610 x 10 -4 T for the four-layered superimposed cylinder, is found to be about 4 times larger than that of a single-BPSCCO cylinder, and is theoretically analyzed by use of a new analysis method. The experimental values of the maximum shielded magnetic flux density B sn of n-layered superimposed cylinders are found to agree well with those of the theoretical analysis. Experimental results revealed several characteristics of the magnetic shielding within the n-layered superimposed cylinders. Also discussed is the new analysis method for the relationship between the n and B sn

Aerodynamic loading on a cylinder behind an airfoil

Energy Technology Data Exchange (ETDEWEB)

Zhang, H.J.; Huang, L.; Zhou, Y. [Hong Kong Polytechnic University, Department of Mechanical Engineering, Kowloon (Hong Kong)

2005-05-01

The interaction between the wake of a rotor blade and a downstream cylinder holds the key to the understanding and control of electronic cooling fan noise. In this paper, the aerodynamic characteristics of a circular cylinder are experimentally studied in the presence of an upstream NACA 4412 airfoil for the cylinder-diameter-based Reynolds numbers of Re{sub d}=2,100-20,000, and the airfoil chord-length-based Reynolds numbers of Re{sub c}=14,700-140,000. Lift and drag fluctuations on the cylinder, and the longitudinal velocity fluctuations of the flow behind the cylinder were measured simultaneously using a load cell and two hot wires, respectively. Data analysis shows that unsteady forces on the cylinder increase significantly in the presence of the airfoil wake. The dependence of the forces on two parameters is investigated, that is, the lateral distance (T) between the airfoil and the cylinder, and the Reynolds number. The forces decline quickly as Tincreases. For Re{sub c}<60,000, the vortices shed from the upstream airfoil make a major contribution to the unsteady forces on the cylinder compared to the vortex shedding from the cylinder itself. For Re{sub c}>60,000, no vortices are generated from the airfoil, and the fluctuating forces on the cylinder are caused by its own vortex shedding. (orig.)

Inner cylinder of the CMS vacuum tank.

CERN Multimedia

Patrice Loïez

2002-01-01

The vacuum tank of the CMS magnet system consists of inner and outer stainless-steel cylinders and houses the superconducting coil. The inner cylinder contains all the barrel sub-detectors, which it supports via a system of horizontal rails. The cylinder is pictured here in the vertical position on a yellow platform mounted on the ferris-wheel support structure. This will allow it to be pivoted and inserted into the outer cylinder already attached to the innermost ring of the barrel yoke.

UF{sub 6} pressure excursions during cylinder heating

Energy Technology Data Exchange (ETDEWEB)

Brown, P.G. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

As liquid UF{sub 6} inside a cylinder changes from a liquid to a solid, it forms a porous solid which occupies approximately the same volume as that of the liquid before cooling. Simultaneously as the liquid cools, UF{sub 6} vapor in the cylinder ullage above the liquid desublimes on the upper region of the inner cylinder wall. This solid is a dense, glass-like material which can accumulate to a significant thickness. The thickness of the solid coating on the upper cylinder wall and directly behind the cylinder valve area will vary depending on the conditions during the cooling stage. The amount of time lapsed between UF{sub 6} solidification and UF{sub 6} liquefaction can also affect the UF{sub 6} coating. This is due to the daily ambient heat cycle causing the coating to sublime from the cylinder wall to cooler areas, thus decreasing the thickness. Structural weakening of the dense UF{sub 6} layer also occurs due to cylinder transport vibration and thermal expansion. During cylinder heating, the UF{sub 6} nearest the cylinder wall will liquefy first. As the solid coating behind the cylinder valve begins to liquefy, it results in increased pressure depending upon the available volume for expansion. At the Paducah Gaseous Diffusion Plant (PGDP) during the liquefaction of the UF{sub 6} in cylinders in the UF{sub 6} feed and sampling autoclaves, this pressure increase has resulted in the activation of the systems rupture discs which are rated at 100 pounds per square inch differential.

Numerical Study of Shock-Cylinder Banks Interactions

International Nuclear Information System (INIS)

Wang, S.P.; Anderson, M.H.; Oakley, J.G.; Bonazza, R.

2003-01-01

A numerical parametric study of shock-cylinder banks interactions is presented using a high resolution Euler solver. Staggered cylinder banks of five rows are chosen with the purpose of modeling IFE reactor cooling tube banks. The effect of the aspect ratio of the intercylinder pitch to the distance between successive cylinder rows on the vertical pressure forces acting on the cylinders with different geometries is investigated. Preliminary results show that the largest vertical force develops on the cylinders of the second or third row. This peak pressure force increases with decreasing values of the aspect ratio. It is shown that an increasing second force peak also appears on the successive rows, starting with the second one, with decreasing aspect ratio. It is also observed that the force on the last-row cylinders basically decreases to the level of that on the first row. The results are useful for the optimal design of the cooling tubes system of IFE reactors

Theoretical and experimental stress analyses of ORNL thin-shell cylinder-to-cylinder model 3

International Nuclear Information System (INIS)

Gwaltney, R.C.; Bolt, S.E.; Corum, J.M.; Bryson, J.W.

1975-06-01

The third in a series of four thin-shell cylinder-to-cylinder models was tested, and the experimentally determined elastic stress distributions were compared with theoretical predictions obtained from a thin-shell finite-element analysis. The models are idealized thin-shell structures consisting of two circular cylindrical shells that intersect at right angles. There are no transitions, reinforcements, or fillets in the junction region. This series of model tests serves two basic purposes: the experimental data provide design information directly applicable to nozzles in cylindrical vessels; and the idealized models provide test results for use in developing and evaluating theoretical analyses applicable to nozzles in cylindrical vessels and to thin piping tees. The cylinder of model 3 had a 10 in. OD and the nozzle had a 1.29 in. OD, giving a d 0 /D 0 ratio of 0.129. The OD/thickness ratios for the cylinder and the nozzle were 50 and 7.68 respectively. Thirteen separate loading cases were analyzed. In each, one end of the cylinder was rigidly held. In addition to an internal pressure loading, three mutually perpendicular force components and three mutually perpendicular moment components were individually applied at the free end of the cylinder and at the end of the nozzle. The experimental stress distributions for all the loadings were obtained using 158 three-gage strain rosettes located on the inner and outer surfaces. The loading cases were also analyzed theoretically using a finite-element shell analysis developed at the University of California, Berkeley. The analysis used flat-plate elements and considered five degrees of freedom per node in the final assembled equations. The comparisons between theory and experiment show reasonably good agreement for this model. (U.S.)

Theoretical and experimental stress analyses of ORNL thin-shell cylinder-to-cylinder model 4

International Nuclear Information System (INIS)

Gwaltney, R.C.; Bolt, S.E.; Bryson, J.W.

1975-06-01

The last in a series of four thin-shell cylinder-to-cylinder models was tested, and the experimentally determined elastic stress distributions were compared with theoretical predictions obtained from a thin-shell finite-element analysis. The models in the series are idealized thin-shell structures consisting of two circular cylindrical shells that intersect at right angles. There are no transitions, reinforcements, or fillets in the junction region. This series of model tests serves two basic purposes: (1) the experimental data provide design information directly applicable to nozzles in cylindrical vessels, and (2) the idealized models provide test results for use in developing and evaluating theoretical analyses applicable to nozzles in cylindrical vessels and to thin piping tees. The cylinder of model 4 had an outside diameter of 10 in., and the nozzle had an outside diameter of 1.29 in., giving a d 0 /D 0 ratio of 0.129. The OD/thickness ratios were 50 and 20.2 for the cylinder and nozzle respectively. Thirteen separate loading cases were analyzed. For each loading condition one end of the cylinder was rigidly held. In addition to an internal pressure loading, three mutually perpendicular force components and three mutually perpendicular moment components were individually applied at the free end of the cylinder and at the end of the nozzle. The experimental stress distributions for each of the 13 loadings were obtained using 157 three-gage strain rosettes located on the inner and outer surfaces. Each of the 13 loading cases was also analyzed theoretically using a finite-element shell analysis developed at the University of California, Berkeley. The analysis used flat-plate elements and considered five degrees of freedom per node in the final assembled equations. The comparisons between theory and experiment show reasonably good agreement for this model. (U.S.)

Cracking investigation of Monju emergency generator C unit cylinder liner. Cylinder liner soundness confirmation by a fall cause of the materials strength of the cylinder liner and the supersonic wave speed

International Nuclear Information System (INIS)

Kobayashi, Takanori; Sakon, Miyoji; Takada, Osamu; Hatori, Masakazu; Sakamoto, Tsutomu; Sato, Toshiyuki; Kazama, Akihito; Ishizawa, Yoshihiro; Igawa, Katsuhisa; Nakae, Hideo

2012-02-01

I confirmed a leak of the effluent gas from cylinder part during a load examination after the check of the emergency generator C unit on December 28, 2010 of the facilities check average and confirmed crack in No.8 cylinder liner part. As a result, because it was not performed oil pressure management properly without attaching an oil pressure gauge when I removed cylinder liner about the cause, crack occurred by having been able to write excessive stress for the cylinder liner and reached damage. By a process of this investigation, a fall of the materials strength of some cylinder liner was confirmed, but because a lead ingredient got mixed with materials by a casting process at the time of the production of the cylinder liner, as for this, Widmannstaetten graphite occurred, and it became clear that materials strength fell. In addition, I performed inspection by the supersonic wave velocity measurement as technique to distinguish this Widmannstaetten graphite easily and confirmed that I was effective. Because this report was the knowledge that there were little inspection contents which modified soundness confirmation technique of the cylinder liner with the possibility of materials strength fall of the cylinder liner by the Widmannstaetten graphite outbreak and the mixture of lead for a report example in the field of cast iron, I gathered it in this report. (author)

Technical Safety Requirements for the Waste Storage Facilities May 2014

Energy Technology Data Exchange (ETDEWEB)

Laycak, D. T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2014-04-16

This document contains the Technical Safety Requirements (TSR) for the Radioactive and Hazardous Waste Management (RHWM) WASTE STORAGE FACILITIES, which include Area 625 (A625) and the Building 693 (B693) Yard Area of the Decontamination and Waste Treatment Facility (DWTF) at LLNL. The TSRs constitute requirements for safe operation of the WASTE STORAGE FACILITIES. These TSRs are derived from the Documented Safety Analyses for the Waste Storage Facilities (DSA) (LLNL 2011). The analysis presented therein concluded that the WASTE STORAGE FACILITIES are low-chemical hazard, Hazard Category 2 non-reactor nuclear facilities. The TSRs consist primarily of inventory limits and controls to preserve the underlying assumptions in the hazard and accident analyses. Further, appropriate commitments to safety programs are presented in the administrative controls sections of the TSRs. The WASTE STORAGE FACILITIES are used by RHWM to handle and store hazardous waste, TRANSURANIC (TRU) WASTE, LOW-LEVEL WASTE (LLW), mixed waste, California combined waste, nonhazardous industrial waste, and conditionally accepted waste generated at LLNL as well as small amounts of waste from other DOE facilities, as described in the DSA. In addition, several minor treatments (e.g., size reduction and decontamination) are carried out in these facilities.

Technical Safety Requirements for the Waste Storage Facilities May 2014

International Nuclear Information System (INIS)

Laycak, D. T.

2014-01-01

This document contains the Technical Safety Requirements (TSR) for the Radioactive and Hazardous Waste Management (RHWM) WASTE STORAGE FACILITIES, which include Area 625 (A625) and the Building 693 (B693) Yard Area of the Decontamination and Waste Treatment Facility (DWTF) at LLNL. The TSRs constitute requirements for safe operation of the WASTE STORAGE FACILITIES. These TSRs are derived from the Documented Safety Analyses for the Waste Storage Facilities (DSA) (LLNL 2011). The analysis presented therein concluded that the WASTE STORAGE FACILITIES are low-chemical hazard, Hazard Category 2 non-reactor nuclear facilities. The TSRs consist primarily of inventory limits and controls to preserve the underlying assumptions in the hazard and accident analyses. Further, appropriate commitments to safety programs are presented in the administrative controls sections of the TSRs. The WASTE STORAGE FACILITIES are used by RHWM to handle and store hazardous waste, TRANSURANIC (TRU) WASTE, LOW-LEVEL WASTE (LLW), mixed waste, California combined waste, nonhazardous industrial waste, and conditionally accepted waste generated at LLNL as well as small amounts of waste from other DOE facilities, as described in the DSA. In addition, several minor treatments (e.g., size reduction and decontamination) are carried out in these facilities.

Approximation of Surfaces by Cylinders

DEFF Research Database (Denmark)

Randrup, Thomas

1998-01-01

We present a new method for approximation of a given surface by a cylinder surface. It is a constructive geometric method, leading to a monorail representation of the cylinder surface. By use of a weighted Gaussian image of the given surface, we determine a projection plane. In the orthogonal...

ASSESSMENT OF THE BACTERIOLOGICAL QUALITY OF COMPOST FROM A YARD WASTE PROCESSING FACILITY

Science.gov (United States)

Citizen concern over possible pathogenic microorganism contamination in compost and in a runoff collection pond prompted a U.S. Environmental Protection Agency (EPA) investigation. One out of eight samples collected from the distribution pile at a yard waste compost processing f...

40 CFR 60.3063 - When must I comply if my air curtain incinerator burns only wood waste, clean lumber, and yard...

Science.gov (United States)

2010-07-01

... incinerator burns only wood waste, clean lumber, and yard waste? 60.3063 Section 60.3063 Protection of... Units That Commenced Construction On or Before December 9, 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3063 When must I comply if my air curtain...

UF{sub 6} cylinder fire test

Energy Technology Data Exchange (ETDEWEB)

Park, S.H. [Oak Ridge K-25 Site, Oak Ridge, TN (United States)

1991-12-31

With the increasing number of nuclear reactors for power generation, there is a comparable increase in the amount of UF{sub 6} being transported. Likewise, the probability of having an accident involving UF{sub 6}-filled cylinders also increases. Accident scenarios which have been difficult to assess are those involving a filled UF{sub 6} cylinder subjected to fire. A study is underway at the Oak Ridge K-25 Site, as part of the US DOE Enrichment Program, to provide empirical data and a computer model that can be used to evaluate various cylinder-in-fire scenarios. It is expected that the results will provide information leading to better handling of possible fire accidents as well as show whether changes should be made to provide different physical protection during shipment. The computer model being developed will be capable of predicting the rupture of various cylinder sizes and designs as well as the amount of UF{sub 6}, its distribution in the cylinder, and the conditions of the fire.

Three-dimensional vortex flow near the endwall of a short cylinder in crossflow: Uniform-diameter circular cylinder

International Nuclear Information System (INIS)

Chen, S.B.; Sanitjai, S.; Ghosh, K.; Goldstein, R.J.

2012-01-01

Flow characteristics, around a short uniform-diameter circular cylinder in crossflow, are investigated experimentally. Extensive flow visualization using oil-lampblack and smoke-wire methods have been performed. Near-wake velocity measurements have been performed using a hotwire anemometer. Complex secondary flows are observed on and around the cylinder in crossflow. Multiple vortices are observed in the horseshoe vortex system near the cylinder–endwall junction. Based on this flow visualization and local mass transfer measurement results, a six-vortex secondary flow model has been proposed. - Highlights: ► Flow visualizations and velocity measurements for a short circular cylinder. ► Six vortices in the horseshoe vortex system upstream of the base of the cylinder. ► Cross-stream turbulence intensity profiles show a similarity in their shape.

Long term storage techniques for 85Kr

International Nuclear Information System (INIS)

Foster, B.A.; Pence, D.T.; Staples, B.A.

1975-01-01

As new nuclear fuel reprocessing plants go on stream, the collection of fission product 85 Kr will be required to avoid potential local release problems and long-term atmospheric buildup. Storage of the collected 85 Kr for a period of at least 100 years will be necessary to allow approximately 99.9 percent decay before it is released. A program designed to develop and evaluate proposed methods for long-term storage of 85 Kr is discussed, and the results of a preliminary evaluation of three methods, high pressure steel cylinders, zeolite encapsulation, and clathrate inclusion are presented. (U.S.)

Engineering product storage under the advanced fuel cycle initiative. Part I: An iterative thermal transport modeling scheme for high-heat-generating radioactive storage forms

International Nuclear Information System (INIS)

Kaminski, Michael D.

2005-01-01

The US Department of Energy is developing an integrated nuclear fuel cycle technology under its Advanced Fuel Cycle Initiative (AFCI). Under the AFCI, waste minimization is stressed. Engineered product storage materials will be required to store concentrated radioactive cesium, strontium, americium, and curium for periods of tens to hundreds of years. The fabrication of such engineered products has some precedence but the concept is largely novel. We thus present a theoretical model used to calculate the maximum radial dimensions of right cylinder storage forms under several scenarios. Maximum dimensions are small, comparable to nuclear fuel pins in some cases, to avoid centerline melting temperatures; this highlights the need for a careful strategy for engineered product storage fabrication and storage

Decomposition and carbon storage of hardwood and softwood branches in laboratory-scale landfills

International Nuclear Information System (INIS)

Wang, Xiaoming; Barlaz, Morton A.

2016-01-01

Tree branches are an important component of yard waste disposed in U.S. municipal solid waste (MSW) landfills. The objective of this study was to characterize the anaerobic biodegradability of hardwood (HW) and softwood (SW) branches under simulated but optimized landfill conditions by measuring methane (CH_4) yields, decay rates, the decomposition of cellulose, hemicellulose and organic carbon, as well as carbon storage factors (CSFs). Carbon conversions to CH_4 and CO_2 ranged from zero to 9.5% for SWs and 17.1 to 28.5% for HWs. When lipophilic or hydrophilic compounds present in some of the HW and SW samples were extracted, some samples showed increased biochemical methane potentials (BMPs). The average CH_4 yield, carbon conversion, and CSF measured here, 59.4 mL CH_4 g"−"1 dry material, 13.9%, and 0.39 g carbon stored g"−"1 dry material, respectively, represent reasonable values for use in greenhouse gas inventories in the absence of detailed wood type/species data for landfilled yard waste. - Highlights: • Characterized biodegradation of branches under simulated but optimized landfill conditions • Observed varied biodegradation between HW and SW branches with different diameters • Inhibitory extractives were observed on boughs or twigs of some branch species. • CH_4 yield and carbon storage factors presented for use in landfill related inventories.

Decomposition and carbon storage of hardwood and softwood branches in laboratory-scale landfills

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiaoming, E-mail: wangxiaoming@cqu.edu.cn [Key Laboratory of Three Gorges Reservoir Region' s Eco-Environment under Ministry of Education, Chongqing University, Chongqing 400044 (China); Department of Civil, Construction, and Environmental Engineering, Campus Box 7908, North Carolina State University, Raleigh, NC 27695-7908 (United States); Barlaz, Morton A. [Department of Civil, Construction, and Environmental Engineering, Campus Box 7908, North Carolina State University, Raleigh, NC 27695-7908 (United States)

2016-07-01

Tree branches are an important component of yard waste disposed in U.S. municipal solid waste (MSW) landfills. The objective of this study was to characterize the anaerobic biodegradability of hardwood (HW) and softwood (SW) branches under simulated but optimized landfill conditions by measuring methane (CH{sub 4}) yields, decay rates, the decomposition of cellulose, hemicellulose and organic carbon, as well as carbon storage factors (CSFs). Carbon conversions to CH{sub 4} and CO{sub 2} ranged from zero to 9.5% for SWs and 17.1 to 28.5% for HWs. When lipophilic or hydrophilic compounds present in some of the HW and SW samples were extracted, some samples showed increased biochemical methane potentials (BMPs). The average CH{sub 4} yield, carbon conversion, and CSF measured here, 59.4 mL CH{sub 4} g{sup −1} dry material, 13.9%, and 0.39 g carbon stored g{sup −1} dry material, respectively, represent reasonable values for use in greenhouse gas inventories in the absence of detailed wood type/species data for landfilled yard waste. - Highlights: • Characterized biodegradation of branches under simulated but optimized landfill conditions • Observed varied biodegradation between HW and SW branches with different diameters • Inhibitory extractives were observed on boughs or twigs of some branch species. • CH{sub 4} yield and carbon storage factors presented for use in landfill related inventories.

Optimization and improvement of Halbach cylinder design

DEFF Research Database (Denmark)

Bjørk, Rasmus; Bahl, Christian Robert Haffenden; Smith, Anders

2008-01-01

possible volume of magnets with a given mean flux density in the cylinder bore. The volume of the cylinder bore could also be significantly increased by only slightly increasing the volume of the magnets, for a fixed mean flux density. Placing additional blocks of magnets on the end faces of the Halbach...... that this parameter was optimal for long Halbach cylinders with small rex. Using the previously mentioned additional blocks of magnets can improve the parameter by as much as 15% as well as improve the homogeneity of the field in the cylinder bore. ©2008 American Institute of Physics...

Thermal enhancement of charge and discharge cycles for adsorbed natural gas storage

KAUST Repository

Rahman, Kazi Afzalur

2011-07-01

The usage of adsorbed natural gas (ANG) storage is hindered by the thermal management during the adsorption and desorption processes. An effective thermal enhancement is thus essential for the development of the ANG technology and the motivation for this study is the investigation of a gas storage system with internal thermal control. We employed a fin-tube type heat exchanger that is placed in a pressurized cylinder. A distributed-parameter model is used for the theoretical modeling and simulations are conducted at assorted charging and discharging conditions. These studies included the transient thermal behaviours of the elements within the ANG-charged cylinder and parameters such as pressure and temperature profiles of adsorbent have been obtained during charge and discharge cycles, and results are compared with a conventional compressed methane vessel. © 2011 Elsevier Ltd. All rights reserved.

Cylinder Position Servo Control Based on Fuzzy PID

Directory of Open Access Journals (Sweden)

Shibo Cai

2013-01-01

Full Text Available The arbitrary position control of cylinder has always been the hard challenge in pneumatic system. We try to develop a cylinder position servo control method by combining fuzzy PID with the theoretical model of the proportional valve-controlled cylinder system. The pressure differential equation of cylinder, pressure-flow equation of proportional valve, and moment equilibrium equation of cylinder are established. And the mathematical models of the cylinder driving system are linearized. Then fuzzy PID control algorithm is designed for the cylinder position control, including the detail analysis of fuzzy variables and domain, fuzzy logic rules, and defuzzification. The stability of the proposed fuzzy PID controller is theoretically proved according to the small gain theorem. Experiments for targets position of 250 mm, 300 mm, and 350 mm were done and the results showed that the absolute error of the position control is less than 0.25 mm. And comparative experiment between fuzzy PID and classical PID verified the advantage of the proposed algorithm.

CHANGING THE LANDSCAPE--LOW-TECH SOLUTIONS TO THE PADUCAH SCRAP METAL REMOVAL PROJECT ARE PROVIDING SAFE, COST-EFFECTIVE REMEDIATION OF CONTAMINATED SCRAP YARDS

International Nuclear Information System (INIS)

Watson, Dan; Eyman, Jeff

2003-01-01

Between 1974 and 1983, contaminated equipment was removed from the Paducah Gaseous Diffusion Plant (PGDP) process buildings as part of an enrichment process upgrade program. The upgrades consisted of the dismantlement, removal, and on-site storage of contaminated equipment, cell components, and scrap material (e.g., metal) from the cascade facilities. Scrap metal including other materials (e.g., drums, obsolete equipment) not related to this upgrade program have thus far accumulated in nine contiguous radiologically-contaminated and non-contaminated scrap yards covering 1.05E5 m2 (26 acres) located in the northwestern portion of the PGDP. This paper presents the sequencing of field operations and methods used to achieve the safe removal and disposition of over 47,000 tonnes (53,000 tons) of metal and miscellaneous items contained in these yards. The methods of accomplishment consist of mobilization, performing nuclear criticality safety evaluations, moving scrap metal to ground level, inspection and segregation, sampling and characterization, scrap metal sizing, packaging and disposal, and finally demobilization. Preventing the intermingling of characteristically hazardous and non-hazardous wastes promotes waste minimization, allowing for the metal and materials to be segregated into 13 separate waste streams. Low-tech solutions such as using heavy equipment to retrieve, size, and package scrap materials in conjunction with thorough planning that integrates safe work practices, commitment to teamwork, and incorporating lessons learned ensures that field operations will be conducted efficiently and safely

Optimized Dose Distribution of Gammamed Plus Vaginal Cylinders

International Nuclear Information System (INIS)

Supe, Sanjay S.; Bijina, T.K.; Varatharaj, C.; Shwetha, B.; Arunkumar, T.; Sathiyan, S.; Ganesh, K.M.; Ravikumar, M.

2009-01-01

Endometrial carcinoma is the most common malignancy arising in the female genital tract. Intracavitary vaginal cuff irradiation may be given alone or with external beam irradiation in patients determined to be at risk for locoregional recurrence. Vaginal cylinders are often used to deliver a brachytherapy dose to the vaginal apex and upper vagina or the entire vaginal surface in the management of postoperative endometrial cancer or cervical cancer. The dose distributions of HDR vaginal cylinders must be evaluated carefully, so that clinical experiences with LDR techniques can be used in guiding optimal use of HDR techniques. The aim of this study was to optimize dose distribution for Gammamed plus vaginal cylinders. Placement of dose optimization points was evaluated for its effect on optimized dose distributions. Two different dose optimization point models were used in this study, namely non-apex (dose optimization points only on periphery of cylinder) and apex (dose optimization points on periphery and along the curvature including the apex points). Thirteen dwell positions were used for the HDR dosimetry to obtain a 6-cm active length. Thus 13 optimization points were available at the periphery of the cylinder. The coordinates of the points along the curvature depended on the cylinder diameters and were chosen for each cylinder so that four points were distributed evenly in the curvature portion of the cylinder. Diameter of vaginal cylinders varied from 2.0 to 4.0 cm. Iterative optimization routine was utilized for all optimizations. The effects of various optimization routines (iterative, geometric, equal times) was studied for the 3.0-cm diameter vaginal cylinder. The effect of source travel step size on the optimized dose distributions for vaginal cylinders was also evaluated. All optimizations in this study were carried for dose of 6 Gy at dose optimization points. For both non-apex and apex models of vaginal cylinders, doses for apex point and three dome

NGSI: Function Requirements for a Cylinder Tracking System

International Nuclear Information System (INIS)

Branney, S.

2012-01-01

While nuclear suppliers currently track uranium hexafluoride (UF 6 ) cylinders in various ways, for their own purposes, industry practices vary significantly. The NNSA Office of Nonproliferation and International Security's Next Generation Safeguards Initiative (NGSI) has begun a 5-year program to investigate the concept of a global monitoring scheme that uniquely identifies and tracks UF 6 cylinders. As part of this effort, NGSI's multi-laboratory team has documented the 'life of a UF 6 cylinder' and reviewed IAEA practices related to UF 6 cylinders. Based on this foundation, this paper examines the functional requirements of a system that would uniquely identify and track UF 6 cylinders. There are many considerations for establishing a potential tracking system. Some of these factors include the environmental conditions a cylinder may be expected to be exposed to, where cylinders may be particularly vulnerable to diversion, how such a system may be integrated into the existing flow of commerce, how proprietary data generated in the process may be protected, what a system may require in terms of the existing standard for UF 6 cylinder manufacture or modifications to it and what the limiting technology factors may be. It is desirable that a tracking system should provide benefit to industry while imposing as few additional constraints as possible and still meeting IAEA safeguards objectives. This paper includes recommendations for this system and the analysis that generated them.

Theory of interacting dislocations on cylinders.

Science.gov (United States)

Amir, Ariel; Paulose, Jayson; Nelson, David R

2013-04-01

We study the mechanics and statistical physics of dislocations interacting on cylinders, motivated by the elongation of rod-shaped bacterial cell walls and cylindrical assemblies of colloidal particles subject to external stresses. The interaction energy and forces between dislocations are solved analytically, and analyzed asymptotically. The results of continuum elastic theory agree well with numerical simulations on finite lattices even for relatively small systems. Isolated dislocations on a cylinder act like grain boundaries. With colloidal crystals in mind, we show that saddle points are created by a Peach-Koehler force on the dislocations in the circumferential direction, causing dislocation pairs to unbind. The thermal nucleation rate of dislocation unbinding is calculated, for an arbitrary mobility tensor and external stress, including the case of a twist-induced Peach-Koehler force along the cylinder axis. Surprisingly rich phenomena arise for dislocations on cylinders, despite their vanishing Gaussian curvature.

Low-Re flow past an isolated cylinder with rounded corners

KAUST Repository

Zhang, Wei

2016-06-29

Direct numerical simulation is performed for flow past an isolated cylinder at Re=1,000. The corners of the cylinder are rounded at different radii, with the non-dimensional radius of curvature varying from R+=R/D=0.000 (square cylinder with sharp corners) to 0.500 (circular cylinder), in which R is the corner radius and D is the cylinder diameter. Our objective is to investigate the effect of the rounded corners on the development of the separated and transitional flow past the cylinder in terms of time-averaged statistics, time-dependent behavior, turbulent statistics and three-dimensional flow patterns. Numerical results reveal that the rounding of the corners significantly reduces the time-averaged drag and the force fluctuations. The wake flow downstream of the square cylinder recovers the slowest and has the largest wake width. However, the statistical quantities do not monotonically vary with the corner radius, but exhibit drastic variations between the cases of square cylinder and partially rounded cylinders, and between the latter and the circular cylinder. The free shear layer separated from the R+=0.125 cylinder is the most stable in which the first roll up of the wake vortex occurs furthest from the cylinder and results in the largest recirculation bubble, whose size reduces as R+ further increases. The coherent and incoherent Reynolds stresses are most pronounced in the near-wake close to the reattachment point, while also being noticeable in the shear layer for the square and R+=0.125 cylinders. The wake vortices translate in the streamwise direction with a convection velocity that is almost constant at approximately 80% of the incoming flow velocity. These vortices exhibit nearly the same trajectory for the rounded cylinders and are furthest away from the wake centerline for the square one. The flow past the square cylinder is strongly three-dimensional as indicated by the significant primary and secondary enstrophy, while it is dominated by the

Self-accelerating parabolic cylinder waves in 1-D

Energy Technology Data Exchange (ETDEWEB)

Yuce, C., E-mail: cyuce@anadolu.edu.tr

2016-11-25

Highlights: • We find a new class of self-accelerating waves. • We show that parabolic cylinder waves self-accelerates in a parabolic potential. • We discuss that truncated parabolic cylinder waves propagates large distance without almost being non-diffracted in free space. - Abstract: We introduce a new self-accelerating wave packet solution of the Schrodinger equation in one dimension. We obtain an exact analytical parabolic cylinder wave for the inverted harmonic potential. We show that truncated parabolic cylinder waves exhibits their accelerating feature.

ES-5052 storage devices on magnetic disks for the BESM-4 computer

International Nuclear Information System (INIS)

Bezrukova, N.B.; Vinogradov, A.F.; Eliseev, G.N.; Ivanchenko, Z.M.; Pervushov, V.I.; Samojlov, V.N.; Stuk, G.P.; Shchelev, S.A.; Chulkov, N.I.

1975-01-01

The basic principles of connection between ES-5052 magnetic disk storage devices and a BESM-4 computer are set forth. The interchange of instructions and guidance information between computer and magnetic disk storage is accomplished through a disk controlling unit. The time taken to find the required cylinder (to pass from track to track) is 20 ms, the access time is 60 to 95 ms. The data transfer rate (512 45-digit machine words) is 20 ms. The total disk storage capacity is equivalent to 250 BESM-4 memory units. The instructions for BESM-4 access to the ES-5052 magnetic disk storage are described

Severe Outbreak of a Yellow Mosaic Disease on the Yard Long Bean in Bogor, West Java

Directory of Open Access Journals (Sweden)

TRI ASMIRA DAMAYANTI

2009-06-01

Full Text Available During 2008 crop season, an outbreak of severe yellow mosaic disease on yard long bean (Vigna unguiculata subsp. Sesquipedalis occurred in several farmers’ fields in West Java. Yard long bean var. Parade inoculated manually with extracts from symptomatic leaves showed the symptoms indicating the presence of virus. Symptomatic leaf samples tested positive in enzyme linked immunosorbent assay (ELISA with antibodies to group specific Potyvirus and Cucumber mosaic virus (CMV. Total RNA derived from symptomatic leaves was subjected to reverse transcription-polymerase chain reaction (RT-PCR using primers specific to the cylindrical inclusion (CI protein of potyviruses and CMV coat protein (CP specific primers. Pair wise comparison of sequences obtained from cloned RT-PCR products with corresponding nucleotide sequences in the GenBank confirmed the presence of Bean common mosaic virus strain Blackeye (BCMV-BlC and CMV in the symptomatic beans. Sequences of BCMV and CMV isolates from the beans showed maximum nucleotide sequence identities (92-97% and (90%, respectively with BCMV-BIC and CMV isolates from Taiwan. Each virus isolate also clustered closely with corresponding isolates from Taiwan in a phylogenetic analyses. These results provide first evidence of the occurrence of multiple infection of BCMV-BIC and CMV in the yard long been from Bogor, West Java.

Application of the exact solution for scattering by an infinite cylinder to the estimation of scattering by a finite cylinder.

Science.gov (United States)

Wang, R T; van de Hulst, H C

1995-05-20

A new algorithm for cylindrical Bessel functions that is similar to the one for spherical Bessel functions allows us to compute scattering functions for infinitely long cylinders covering sizes ka = 2πa/λ up to 8000 through the use of only an eight-digit single-precision machine computation. The scattering function and complex extinction coefficient of a finite cylinder that is seen near perpendicular incidence are derived from those of an infinitely long cylinder by the use of Huygens's principle. The result, which contains no arbitrary normalization factor, agrees quite well with analog microwave measurements of both extinction and scattering for such cylinders, even for an aspect ratio p = l/(2a) as low as 2. Rainbows produced by cylinders are similar to those for spherical drops but are brighter and have a lower contrast.

Cleanup operations at the Oak Ridge Gaseous Diffusion Plant contaminated metal scrapyard

International Nuclear Information System (INIS)

Williams, L.C.

1987-01-01

Cleanup operations at the contaminated metal storage yard located at the Oak Ridge, Tennessee, Gaseous Diffusion Plant have been completed. The storage yard, in existence since the early 1970s, contained an estimated 35,000 tons of mixed-type metals spread over an area of roughly 30 acres. The overall cleanup program required removing the metal from the storage yard, sorting by specific metal types, and size reduction of specific types for future processing. This paper explains the methods and procedures used to accomplish this task

46 CFR 58.30-30 - Fluid power cylinders.

Science.gov (United States)

2010-10-01

... all pneumatic power transmission systems. (b) Fluid power cylinders consisting of a container and a... 46 Shipping 2 2010-10-01 2010-10-01 false Fluid power cylinders. 58.30-30 Section 58.30-30... MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-30 Fluid power cylinders. (a) The...

Nonlinear bending and collapse analysis of a poked cylinder and other point-loaded cylinders

International Nuclear Information System (INIS)

Sobel, L.H.

1983-06-01

This paper analyzes the geometrically nonlinear bending and collapse behavior of an elastic, simply supported cylindrical shell subjected to an inward-directed point load applied at midlength. The large displacement analysis results for this thin (R/t = 638) poked cylinder were obtained from the STAGSC-1 finite element computer program. STAGSC-1 results are also presented for two other point-loaded shell problems: a pinched cylinder (R/t = 100), and a venetian blind (R/t = 250)

Experimental seismic test of fluid coupled co-axial cylinders

International Nuclear Information System (INIS)

Chu, M.L.; Brown, S.J.; Lestingi, J.F.

1979-01-01

The dynamic response of fluid coupled coaxial cylindrical shells is of interest to the nuclear industry with respect to the seismic design of the reactor vessel and thermal liner. The experiments described present a series of tests which investigate the effect of the annular clearance between the cylinders (gap) on natural frequency, damping, and seismic response of both the inner and outer cylinders. The seismic input is a time history base load to the flexible fluid filled coaxial cylinders. The outer cylinder is elastically supported at both ends while the inner cylinder is supported only at the base (lower) end

Low-Re flow past an isolated cylinder with rounded corners

KAUST Repository

Zhang, Wei; Samtaney, Ravi

2016-01-01

rounded cylinders, and between the latter and the circular cylinder. The free shear layer separated from the R+=0.125 cylinder is the most stable in which the first roll up of the wake vortex occurs furthest from the cylinder and results in the largest

Label inspection of approximate cylinder based on adverse cylinder panorama

Science.gov (United States)

Lin, Jianping; Liao, Qingmin; He, Bei; Shi, Chenbo

2013-12-01

This paper presents a machine vision system for automated label inspection, with the goal to reduce labor cost and ensure consistent product quality. Firstly, the images captured from each single-camera are distorted, since the inspection object is approximate cylindrical. Therefore, this paper proposes an algorithm based on adverse cylinder projection, where label images are rectified by distortion compensation. Secondly, to overcome the limited field of viewing for each single-camera, our method novelly combines images of all single-cameras and build a panorama for label inspection. Thirdly, considering the shake of production lines and error of electronic signal, we design the real-time image registration to calculate offsets between the template and inspected images. Experimental results demonstrate that our system is accurate, real-time and can be applied for numerous real- time inspections of approximate cylinders.

A Study of Gas Economizing Pneumatic Cylinder

International Nuclear Information System (INIS)

Li, T C; Wu, H W; Kuo, M J

2006-01-01

The pneumatic cylinder is the most typical actuator in the pneumatic equipment, and its mechanism is so simple that it is often used to operate point to point driving without the feedback loop in various automatic machines. But, the energy efficiency of pneumatic system is very poor compared with electrical systems and hydraulic systems. So, it is very important to discuss the energy saving for the pneumatic cylinder systems. In this thesis, we proposed three methods to apply the reduction in the air consumed for pneumatic cylinder systems. An air charge accumulator is used to absorb the exhausted compress air and a boost valve boosted the air to the higher pressure for used again. From the experiments, the direct used cylinder exhaust air may save about 40% of compress air

Enrichment Assay Methods Development for the Integrated Cylinder Verification System

Energy Technology Data Exchange (ETDEWEB)

Smith, Leon E.; Misner, Alex C.; Hatchell, Brian K.; Curtis, Michael M.

2009-10-22

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders taken to be representative of the facility's entire product-cylinder inventory. Pacific Northwest National Laboratory (PNNL) is developing a concept to automate the verification of enrichment plant cylinders to enable 100 percent product-cylinder verification and potentially, mass-balance calculations on the facility as a whole (by also measuring feed and tails cylinders). The Integrated Cylinder Verification System (ICVS) could be located at key measurement points to positively identify each cylinder, measure its mass and enrichment, store the collected data in a secure database, and maintain continuity of knowledge on measured cylinders until IAEA inspector arrival. The three main objectives of this FY09 project are summarized here and described in more detail in the report: (1) Develop a preliminary design for a prototype NDA system, (2) Refine PNNL's MCNP models of the NDA system, and (3) Procure and test key pulse-processing components. Progress against these tasks to date, and next steps, are discussed.

Enrichment Assay Methods Development for the Integrated Cylinder Verification System

International Nuclear Information System (INIS)

Smith, Leon E.; Misner, Alex C.; Hatchell, Brian K.; Curtis, Michael M.

2009-01-01

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders taken to be representative of the facility's entire product-cylinder inventory. Pacific Northwest National Laboratory (PNNL) is developing a concept to automate the verification of enrichment plant cylinders to enable 100 percent product-cylinder verification and potentially, mass-balance calculations on the facility as a whole (by also measuring feed and tails cylinders). The Integrated Cylinder Verification System (ICVS) could be located at key measurement points to positively identify each cylinder, measure its mass and enrichment, store the collected data in a secure database, and maintain continuity of knowledge on measured cylinders until IAEA inspector arrival. The three main objectives of this FY09 project are summarized here and described in more detail in the report: (1) Develop a preliminary design for a prototype NDA system, (2) Refine PNNL's MCNP models of the NDA system, and (3) Procure and test key pulse-processing components. Progress against these tasks to date, and next steps, are discussed.

Sub-wavelength metamaterial cylinders with multiple dipole resonances

DEFF Research Database (Denmark)

Arslanagic, Samel; Breinbjerg, Olav

2009-01-01

It has been shown that the sub-wavelength resonances of the individual MTM cylinders also occur for electrically small configurations combining 2 or 4 cylinders. For the 2-and 4-cylinder configurations the overall size is 1/20 and 1/12.5 of the smallest wavelength, respectively. These MTM...... configuration thus offer the possibility for multi-resonant electrically small configurations....

Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders

NARCIS (Netherlands)

De Kanter, J.L.C.G.

2006-01-01

Summary accompanying the thesis: Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders by Jens de Kanter This thesis presents the investigation of the crush behaviour of both monolithic aluminium cylinders and externally fibre reinforced aluminium cylinders. The research is based

Modelling and Metaheuristic for Gantry Crane Scheduling and Storage Space Allocation Problem in Railway Container Terminals

Directory of Open Access Journals (Sweden)

Ming Zeng

2017-01-01

Full Text Available The gantry crane scheduling and storage space allocation problem in the main containers yard of railway container terminal is studied. A mixed integer programming model which comprehensively considers the handling procedures, noncrossing constraints, the safety margin and traveling time of gantry cranes, and the storage modes in the main area is formulated. A metaheuristic named backtracking search algorithm (BSA is then improved to solve this intractable problem. A series of computational experiments are carried out to evaluate the performance of the proposed algorithm under some randomly generated cases based on the practical operation conditions. The results show that the proposed algorithm can gain the near-optimal solutions within a reasonable computation time.

MONOMIALS AND BASIN CYLINDERS FOR NETWORK DYNAMICS.

Science.gov (United States)

Austin, Daniel; Dinwoodie, Ian H

We describe methods to identify cylinder sets inside a basin of attraction for Boolean dynamics of biological networks. Such sets are used for designing regulatory interventions that make the system evolve towards a chosen attractor, for example initiating apoptosis in a cancer cell. We describe two algebraic methods for identifying cylinders inside a basin of attraction, one based on the Groebner fan that finds monomials that define cylinders and the other on primary decomposition. Both methods are applied to current examples of gene networks.

Deflagration in stainless steel storage containers containing plutonium dioxide

International Nuclear Information System (INIS)

Kleinschmidt, P.D.

1996-02-01

Detonation of hydrogen and oxygen in stainless steel storage containers produces maximum pressures of 68.5 psia and 426.7 psia. The cylinders contain 3,000 g of PuO 2 with 0.05 wt% and 0.5 wt% water respectively. The hydrogen and oxygen are produced by the alpha decomposition of the water. Work was performed for the Savannah River Site

Imperfection effects on the buckling of hydrostatically loaded cylinders

DEFF Research Database (Denmark)

Pinna, Rodney; Madsen, Søren

2015-01-01

imperfection sensitivity. Work on cylinders with other loading conditions, such as hydrostatic loading, is more limited. Similarly, there is limited work on cylinders with boundary conditions other than simply-supported ends. This paper looks at the case of cylinders under hydrostatic load, which is often...

Dynamic Measurement of Extra Long Stroke Cylinder in the Pneumatic System

International Nuclear Information System (INIS)

Chang Ho; Lan Chouwei; Chen, L-C

2006-01-01

This paper sets up the measure and control system of the dynamic characteristics of the extra long stroke cylinder. In the different types of the control conditions (e.g. different control law, operating pressure and direct control valves), using the measure and control system to measure the relation between the pressure and the velocity of the motion of the long stroke cylinder and to observe the stick slip phenomenon of the motion of the long stroke cylinder. In the innovate measurement system, two pressure sensors are set on the long stroke cylinder to measure the difference of the pressure between the inlet and the exhaust of the long stroke cylinder. In additions, a draw line encoder is set on the system to measure the position and the velocity of the motion of the long stroke cylinder. The measuring data of the measure system is transferred to the computer via A/D interface card and counter card, and Home-made program of Haptic Interface Device is used to control the system, saving the data of the motion of the long stroke cylinder. The system uses different types of direction control valve to control the motion of the long stroke cylinder and compares the difference of the motion of the long stroke cylinder. The results show that the motion of the cylinder that pauses in the middle of the cylinder stroke and causes the stick slip phenomenon is more violent than the stick slip phenomenon in other position. When the length of the pause time reaches the some range, the acceleration of the motion of the cylinder will be rised substantially. This paper not only focuses on the testing method of the dynamic characteristics of the motion of the long stroke cylinder, but also includes the analysis of the dynamic characteristics of the motion of the long stroke cylinder. It provides the data of the dynamic characteristics of the motion of the long stroke cylinder to improve and design the pneumatic system of the long stroke cylinder

Energy Saving Potential in Knuckle Boom Cranes using a Novel Pump Controlled Cylinder Drive

Directory of Open Access Journals (Sweden)

Søren Ketelsen

2018-04-01

Full Text Available This paper is considering the application of a novel pump controlled cylinder drive, the so-called Speed-variable Switched Differential Pump (SvSDP, for knuckle boom crane actuation. Especially the control system for the SvSDP drive is considered, and aiming on improving energy efficiency a refinement of the existing control structure is proposed. An energy efficient sizing algorithm for the SvSDP drive is developed, and fundamental differences between the achievable operating range for the SvSDP drive compared to a conventional valve-cylinder drive are discussed. A case study is conducted with knuckle boom crane actuation, and compared to a conventional valve actuation. Simulation results show that the motion tracking performance is on a similar level compared to the valve actuation approach, while the energy consumption is drastically decreased. For the given test trajectory the valve actuation system consumes 0.79 kWh of electrical energy, while the SvSDP drive consume 0.06 kWh, if ideal energy recovery and storage is assumed.

Inner and outer cylinders of the CMS vacuum tank.

CERN Multimedia

Patrice Loïez

2002-01-01

The vacuum tank of the CMS magnet system consists of inner and outer stainless-steel cylinders and houses the superconducting coil. The inner cylinder contains all the barrel sub-detectors, which it supports via a system of horizontal rails. The cylinder is pictured here in the vertical position on a yellow platform mounted on the ferris-wheel support structure. This will allow it to be pivoted and inserted into the already installed outer cylinder, through which this photo was taken.

Flow past two tandem square cylinders vibrating transversely in phase

International Nuclear Information System (INIS)

Mithun, M G; Tiwari, Shaligram

2014-01-01

Numerical investigations have been carried out to study the wake characteristics of flow past two tandem square cylinders vibrating in phase. Both the cylinders vibrate in a transverse direction, i.e., perpendicular to the incoming flow with the same frequency and amplitude. The frequency of vibration of the cylinders and the inter-cylinder spacing are varied for fixed values of the Reynolds number (Re = 100) and the amplitude ratio (A/D = 0.4). The synchronous or lock-in regime for the oscillatory wake of the vibrating cylinders has been identified by varying the frequency of the vibration from f e  = 0.4 f 0 to 1.6 f 0 (f 0 being the frequency of vortex shedding behind a stationary square cylinder). The characteristics of lift and drag and the mechanism of vortex shedding are studied by varying the excitation frequency within the lock-in range for each value of inter-cylinder spacing. The complex interaction of flow between the cylinders gives rise to a variety of characteristically different shedding patterns in their wake. For values of inter-cylinder spacing equal to 2D and 3D, periodic, as well as quasi-periodic, lock-in behaviors are observed in the synchronous range. (paper)

Monitoring Dangerous Goods in Container Yard Using the Internet of Things

OpenAIRE

Ding, Lianhong; Chen, Yifan; Li, Juntao

2016-01-01

The Internet of Things (IoT), a network of objects, has been regarded as the next revolution for the global information industry after the Internet. With IoT, many intelligent applications can be accomplished or improved. This paper presents a framework for dangerous goods management in container yard using IoT technology. The framework consists of three layers: perceptual layer, transport layer, and application layer. It offers an infrastructure for management and data analysis and utilizati...

Method of assembling spent nuclear fuel storage rack

International Nuclear Information System (INIS)

Igarashi, Ryokichi; Hasegawa, Hidenobu.

1982-01-01

Purpose: To improve the safety of a spent fuel storage rack by stably installing the spent fuel in a pool without using supporting beams. Constitution: A restricted unit is composed of a plurality of spuare cylinders. A plurality of such restricted units are aligned in a direction perpendicularly to the arraying direction of the cylinders in the respective restricted units, are coupled with long connecting plates, and are fixed by welding on a common small base, thereby forming a restricted body. According to such assembling method, a plurality of restricted bodies are connected in a direction that the respective restricted bodies are readily overturned, and are secured to the common base. Accordingly, the restricted bodies can be stably installed in a pool without using supporting beams as the conventional one. (Sekiya, K.)

76 FR 38697 - High Pressure Steel Cylinders From China

Science.gov (United States)

2011-07-01

... imports from China of high pressure steel cylinders, provided for in subheading 7311.00.00 of the... threatened with material injury by reason of LTFV and subsidized imports of high pressure steel cylinders... contained in USITC Publication 4241 (July 2011), entitled High Pressure Steel Cylinders from China...

Experiments of flow-induced in-line oscillation of a circular cylinder in a water tunnel. 2. Influence of the aspect ratio of a cantilevered circular cylinder

International Nuclear Information System (INIS)

Nakamura, Akira; Okajima, Atsushi; Kosugi, Takashi

2001-01-01

The flow-induced in-line oscillation of a cantilevered circular cylinder was experimentally studied through free-oscillation tests in a water tunnel. The response displacement amplitude at a circular cylinder tip was measured at reduced velocity from 1.0 to 4.0. A cantilevered cylinder was supported by a plate spring mounted on the water tunnel wall. The cylinder aspect ratio was varied from 5 to 21 to investigate the effect of aspect ratio on the response displacement. It is found that cylinders with aspect ratios of 5 and 10 have one excitation region, while cylinders with aspect ratios of 14 and 21 have two excitation regions. The aspect ratio, therefore, affects the amplitude of the excitation regions. The influence of end-effect was also investigated using cylinders with an end plate attached to the free end. Since the cylinders with an end plate show two excitation regions, even at an aspect ratio of 5, the flow around the free end of a cantilevered cylinder causes the end-effect. The mechanism of vibration was investigated using a cylinder with a splitter plate in wake to prevent alternate vortices. The amplitude is greater than those of a normal cylinder without a splitter plate, especially at V r =2.3 to 3.0, where a cylinder with an end plate shows the second excitation region. In order words, the alternate vortices suppress the amplitude in this range. The maximum amplitude of each excitation region decreases in proportion to C n and the amplitude of the first excitation is more sensitive to C n . (author)

Parametric design studies of toroidal magnetic energy storage units

International Nuclear Information System (INIS)

Herring, J.S.

1990-01-01

Superconducting magnetic energy storage (SMES) units have a number of advantages as storage devices. Electrical current is the input, output and stored medium, allowing for completely solid-state energy conversion. The magnets themselves have no moving parts. The round-trip efficiency is higher than those for batteries, compressed air or pumped hydro. Output power can be very high, allowing complete discharge of the unit within a few seconds. Finally, the unit can be designed for a very large number of cycles, limited basically by fatigue in the structural components. A small systems code has been written to produce and evaluate self-consistent designs for toroidal superconducting energy storage units. The units can use either low temperature or high temperature superconductors. The coils have 'D' shape where the conductor and its stabilizer/structure is loaded only in tension and the centering forces are borne by a bucking cylinder. The coils are convectively cooled from a cryogenic reservoir in the bore of the coils. The coils are suspended in a cylindrical metal shell which protects the magnet during rail, automotive or shipboard use. It is important to note that the storage unit does not rely on its surroundings for structural support, other than normal gravity and inertial loads. This paper presents designs for toroidal energy storage units produced by the systems code. A wide range of several parameters have been considered, resulting in units storing from 1 MJ to 72 GJ. Maximum fields range from 5 t to 20 T. The masses and volumes of the coils, bucking cylinder, coolant, insulation and outer shell are calculated. For unattended use, the allowable operating time using only the boiloff of the cryogenic fluid for refrigeration is calculated. For larger units, the coils have been divided into modules suitable for normal truck or rail transport. 8 refs., 5 tabs

Parametric design studies of toroidal magnetic energy storage units

Science.gov (United States)

Herring, J. Stephen

Superconducting magnetic energy storage (SMES) units have a number of advantages as storage devices. Electrical current is the input, output and stored medium, allowing for completely solid-state energy conversion. The magnets themselves have no moving parts. The round trip efficiency is higher than those for batteries, compressed air or pumped hydro. Output power can be very high, allowing complete discharge of the unit within a few seconds. Finally, the unit can be designed for a very large number of cycles, limited basically by fatigue in the structural components. A small systems code was written to produce and evaluate self-consistent designs for toroidal superconducting energy storage units. The units can use either low temperature or high temperature superconductors. The coils have D shape where the conductor and its stabilizer/structure is loaded only in tension and the centering forces are borne by a bucking cylinder. The coils are convectively cooled from a cryogenic reservoir in the bore of the coils. The coils are suspended in a cylindrical metal shell which protects the magnet during rail, automotive or shipboard use. It is important to note that the storage unit does not rely on its surroundings for structural support, other than normal gravity and inertial loads. Designs are presented for toroidal energy storage units produced by the systems code. A wide range of several parameters have been considered, resulting in units storing from 1 MJ to 72 GJ. Maximum fields range from 5 T to 20 T. The masses and volumes of the coils, bucking cylinder, coolant, insulation and outer shell are calculated. For unattended use, the allowable operating time using only the boiloff of the cryogenic fluid for refrigeration is calculated. For larger units, the coils were divided into modules suitable for normal truck or rail transport.

78 FR 56775 - Waste Confidence-Continued Storage of Spent Nuclear Fuel

Science.gov (United States)

2013-09-13

... structures that are constructed from thick, reinforced concrete walls and slabs that vary between 0.7 and 3... are being proposed to address continued storage for license renewal? C. Decision C1. Introduction C2... confinement of the spent fuel. Each cylinder is surrounded by additional steel, concrete, or other material to...

Modeling flow for modified concentric cylinder rheometer geometry

Science.gov (United States)

Ekeruche, Karen; Connelly, Kelly; Kavehpour, H. Pirouz

2016-11-01

Rheology experiments on biological fluids can be difficult when samples are limited in volume, sensitive to degradation, and delicate to extract from tissues. A probe-like geometry has been developed to perform shear creep experiments on biological fluids and to use the creep response to characterize fluid material properties. This probe geometry is a modified concentric cylinder setup, where the gap is large and we assume the inner cylinder rotates in an infinite fluid. To validate this assumption we perform shear creep tests with the designed probe on Newtonian and non-Newtonian fluids and vary the outer cylinder container diameter. We have also created a numerical model based on the probe geometry setup to compare with experimental results at different outer cylinder diameters. A creep test is modeled by applying rotation to the inner cylinder and solving for the deformation of the fluid throughout the gap. Steady state viscosity values are calculated from creep compliance curves and compared between experimental and numerical results.

Natural convection heat transfer on two horizontal cylinders in liquid sodium

Energy Technology Data Exchange (ETDEWEB)

Hata, K.; Shiotsu, M.; Takeuchi, Y. [Institute of Atomic Energy, Kyoto Univ. (Japan)] [and others

1995-09-01

Natural convection heat transfer on two horizontal 7.6 mm diameter test cylinders assembled with the ratio of the distance between each cylinder axis to the cylinder diameter, S/D, of 2 in liquid sodium was studied experimentally and theoretically. The heat transfer coefficients on the cylinder surface due to the same heat inputs ranging from 1.0 X 10{sup 7} to 1.0 x 10{sup 9} W/m{sup 3} were obtained experimentally for various setting angeles, {gamma}, between vertical direction and the plane including both of these cylinder axis over the range of zero to 90{degrees}. Theoretical equations for laminar natural convection heat transfer from the two horizontal cylinders were numerically solved for the same conditions as the experimental ones considering the temperature dependence of thermophysical properties concerned. The average Nusselt numbers, Nu, values on the Nu versus modified Rayleigh number, R{sub f}, graph. The experimental values of Nu for the upper cylinder are about 20% lower than those for the lower cylinder at {gamma} = 0{degrees} for the range of R{sub f} tested here. The value of Nu for the upper cylinder becomes higher and approaches that for the lower cylinder with the increase in {gamma} over range of 0 to 90{degrees}. The values of Nu for the lower cylinder at each {gamma} are almost in agreement with those for a single cylinder. The theoretical values of Nu on two cylinders except those for R{sub f}<4 at {gamma} = 0{degrees} are in agreement with the experimental data at each {gamma} with the deviations less than 15%. Correlations for Nu on the upper and lower cylinders were obtained as functions of S/D and {gamma} based n the theoretical solutions for the S/D ranged over 1.5 to 4.0.

A new framework to assess risk for a spent fuel dry storage facility

International Nuclear Information System (INIS)

Ryu, J. H.; Jae, M. S.; Jung, C. W.

2004-01-01

A spent fuel dry storage facility is a dry cooling storage facility for storing irradiated nuclear fuel and associated radioactive materials. It has very small possibilities to release radiation materials. It means a safety analysis for a spent fuel dry storage facility is required before construction. In this study, a new framework for assessing risk associated with a spent fuel dry storage facility is represented. A safety assessment framework includes 3 modules such as assessment of basket/cylinder failure rates, that of overall storage system, and site modeling. A reliability physics model for failure rates, event tree analysis(ETA)/fault tree analysis for system analysis, Bayesian analysis for initial events data, and MACCS code for consequence analysis have been used in this study

Carbon fiber reinforced hierarchical orthogrid stiffened cylinder: Fabrication and testing

Science.gov (United States)

Wu, Hao; Lai, Changlian; Sun, Fangfang; Li, Ming; Ji, Bin; Wei, Weiyi; Liu, Debo; Zhang, Xi; Fan, Hualin

2018-04-01

To get strong, stiff and light cylindrical shell, carbon fiber reinforced hierarchical orthogrid stiffened cylinders are designed and fabricated. The cylinder is stiffened by two-scale orthogrid. The primary orthogrid has thick and high ribs and contains several sub-orthogrid cells whose rib is much thinner and lower. The primary orthogrid stiffens the bending rigidity of the cylinder to resist the global instability while the sub-orthogrid stiffens the bending rigidity of the skin enclosed by the primary orthogrid to resist local buckling. The cylinder is fabricated by filament winding method based on a silicone rubber mandrel with hierarchical grooves. Axial compression tests are performed to reveal the failure modes. With hierarchical stiffeners, the cylinder fails at skin fracture and has high specific strength. The cylinder will fail at end crushing if the end of the cylinder is not thickened. Global instability and local buckling are well restricted by the hierarchical stiffeners.

A characteristic analysis of the fluidic muscle cylinder

Science.gov (United States)

Kim, Dong-Soo; Bae, Sang-Kyu; Hong, Sung-In

2005-12-01

The fluidic muscle cylinder consists of an air bellows tube, flanges and lock nuts. It's features are softness of material and motion, simplicity of structure, low production cost and high power efficiency. Recently, unlikely the pneumatic cylinder, the fluidic muscle cylinder without air leakage, stick slip, friction, and seal was developed as a new concept actuator. It has the characteristics such as light weight, low price, high response, durable design, long life, high power, high contraction, which is innovative product fulfilling RT(Robot Technology) which is one of the nation-leading next generation strategy technologies 6T as well as cleanness technology. The application fields of the fluidic muscle cylinder are so various like fatigue tester, brake, accelerator, high technology testing device such as driving simulator, precise position, velocity, intelligent servo actuator under special environment such as load controlling system, and intelligent robot. In this study, we carried out the finite element modeling and analysis about the main design variables such as contraction ration and force, diameter increment of fluidic muscle cylinder. On the basis of finite element analysis, the prototype of fluidic muscle cylinder was manufactured and tested. Finally, we compared the results between the test and the finite element analysis.

Image analysis of moving seeds in an indented cylinder

DEFF Research Database (Denmark)

Buus, Ole; Jørgensen, Johannes Ravn

2010-01-01

inspection in seed cleaning equipment. A prototype of an indented cylinder will be constructed. To make it more dynamic, the cylinder itself will be manufactured using 3D printing technology. The input will come either from 3D scans of existing cylinders or by defining their topology using parametric B...

Beating motion of a circular cylinder in vortex-induced vibrations

Science.gov (United States)

Shen, Linwei; Chan, Eng-Soon; Wei, Yan

2018-04-01

In this paper, beating phenomenon of a circular cylinder in vortex-induced vibration is studied by numerical simulations in a systematic manner. The cylinder mass coefficients of 2 and 10 are considered, and the Reynolds number is 150. Two distinctive frequencies, namely cylinder oscillation and vortex shedding frequencies, are obtained from the harmonic analysis of the cylinder displacement. The result is consistent with that observed in laboratory experiments. It is found that the cylinder oscillation frequency changes with the natural frequency of the cylinder while the reduced velocity is varied. The added-mass coefficient of the cylinder in beating motion is therefore estimated. Meanwhile, the vortex shedding frequency does not change dramatically in the beating situations. In fact, it is very close to 0.2. Accordingly, the lift force coefficient has two main components associated with these two frequencies. Besides, higher harmonics of the cylinder oscillation frequency appear in the spectrum of the lift coefficient. Moreover, the vortex shedding timing is studied in the beating motion by examining the instantaneous flow fields in the wake, and two scenarios of the vortex formation are observed.

Inflation of polymer melts into elliptic and circular cylinders

DEFF Research Database (Denmark)

Rasmussen, Henrik Koblitz; Christensen, Jens Horslund; Gøttsche, Søren

2000-01-01

A thin sheet (membrane) of the polymeric material is clamped between a Teflon-coated thermostated plate and a thermostated aluminium cylinder. By applying thermostated air through the plate, the polymer membrane deforms into an elliptic or a circular cylinder. The position of the top of the infla......A thin sheet (membrane) of the polymeric material is clamped between a Teflon-coated thermostated plate and a thermostated aluminium cylinder. By applying thermostated air through the plate, the polymer membrane deforms into an elliptic or a circular cylinder. The position of the top...

Electromagnetic forces on type-II superconducting rotating cylinders

International Nuclear Information System (INIS)

Saif, A.G.; Refai, T.F.; El-Sabagh, M.A.

1995-01-01

Analytical solutions of the electromagnetic fields are presented for a system composed of an infinitely long superconducting cylinder rotating about its axis and placed parallel to two infinitely long normal conducting wires. Both wires carry the same alternating current. From the obtained electromagnetic fields the electromagnetic power loss on the cylinder surface, electromagnetic forces due to induced currents, electromagnetic torque, and the work opposing the rotation of the cylinder are calculated. (orig.)

Flow induced by a skewed vortex cylinder

DEFF Research Database (Denmark)

Branlard, Emmanuel Simon Pierre

2017-01-01

The velocity field induced by a skewed vortex cylinder of longitudinal and tangential vorticity is derived in this chapter by direct integration of the Biot– Savart law. The derivation steps are provided in details. The results of Castles and Durham for the skewed semi-infinite cylinder....... The content of this chapter is based on the publication of the author entitled "Cylindrical vortex wake model: skewed cylinder, application to yawed or tilted rotors" [1]. Results from this chapter are applied: in Chap. 21 to model a wind turbine (or rotor) in yaw, in Chap. 22 to derive a new yaw...

Oscillatory Stokes Flow Past a Slip Cylinder

Science.gov (United States)

Palaniappan, D.

2013-11-01

Two-dimensional transient slow viscous flow past a circular cylinder with Navier slip boundary conditions is considered in the limit of low-Reynolds number. The oscillatory Stokes flow problem around a cylinder is solved using the stream function method leading to an analytic solution in terms of modified Bessel functions of the second kind. The corresponding steady-state behavior yields the familiar paradoxical result first detected by Stokes. It is noted that the two key parameters, viz., the frequency λ, and the slip coefficient ξ have a significant impact on the flow field in the vicinity of the cylinder contour. In the limit of very low frequency, the flow is dominated by a term containing a well-known biharmonic function found by Stokes that has a singular behavior at infinity. Local streamlines for small times show interesting flow patterns. Attached eddies due to flow separation - observed in the no-slip case - either get detached or pushed away from the cylinder surface as ξ is varied. Computed asymptotic results predict that the flow exhibits inviscid behavior far away from the cylinder in the frequency range 0 < λ << 1 . Although the frequency of oscillations is finite, our exact solutions reveal fairly rapid transitions in the flow domain. Research Enhancement grant, TAMUCC.

Prediction of external corrosion for steel cylinders

International Nuclear Information System (INIS)

Lyon, B.F.

1997-02-01

The US Department of Energy (DOE) currently manages the UF 6 Cylinder Program (the program). The program was formed to address the depleted-uranium hexafluoride (UF 6 ) stored in approximately 50,000 carbon steel cylinders. The cylinders are located at three DOE sites: the K-25 site (K-25) at Oak Ridge, Tennessee; the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The System Requirements Document (SRD) (LMES 1996a) delineates the requirements of the program. The appropriate actions needed to fulfill these requirements are then specified within the System Engineering Management Plan (SEMP) (LMES 1996b). The report presented herein documents activities that in whole or in part satisfy specific requirements and actions stated in the UF 6 Cylinder Program SRD and SEMP with respect to forecasting cylinder conditions. The wall thickness projections made in this report are based on the assumption that the corrosion trends noted will continue. Some activities planned may substantially reduce the rate of corrosion, in which case the results presented here are conservative. The results presented here are intended to supersede those presented previously, as the quality of several of the datasets has improved

Microgrid Controller Design, Implementation, and Deployment: A Journey from Conception to Implementation at the Philadelphia Navy Yard

Energy Technology Data Exchange (ETDEWEB)

Uluski, R.; Kumar, J.; Venkata, S. S. Mani; Vishwakarma, D.; Schneider, K.; Mehrizi-Sani, Ali; Terry, Rudy; Agate, Will

2017-07-01

The Philadelphia Navy Yard is a fast-evolving community microgrid, currently home to over 150 companies and four Navy activity centers occupying nearly 7 million ft2 of buildings in which approximately 12,000 people are employed. The Navy Yard (TNY) is a national center of excellence for energy research, education, and commercialization, focused specifically on community microgrid design and development. TNY microgrid is equipped with the most cost-effective and sustainable means for meeting electric capacity and energy needs through renewable resources, energy efficiency, and distribution grid infrastructure. This article briefly describes how the community microgrid was conceived and planned to produce a great success story of microgrid implementation and the details of the design, development, and implementation of the TNY microgrid controller.

Vortex structure behind highly heated two cylinders in parallel arrangements

International Nuclear Information System (INIS)

Kurita, Eiichirou; Yahagi, Yuji

2008-01-01

Vortex structures behind twin, highly heated cylinders in parallel arrangements have been investigated experimentally. The experiments were conducted under the following conditions: cylinder diameter, D=4 mm; mean flow velocity, U ∞ =1.0 m/s; Reynolds number, Re=250; cylinder clearance, S/D=0.5 - 1.4; and cylinder heat flux, q=0 - 72.6 kW/m 2 . For S/D > 1.2, the Karman vortex street is formed alternately behind each cylinder divided on the slit flow. The slit flow velocity increases with a decrease in S/D and decreases with increasing heat flux. For S/D 2 ). As a result, the increased local kinematic viscosity and S/D play a key role for the vortex structure and formation behind arrangements of two parallel cylinders. (author)

Controlling chaos in a fluid flow past a movable cylinder

International Nuclear Information System (INIS)

Vallejo, Juan C.; Marino, Ines P.; Sanjuan, Miguel A.F.; Kurths, Juergen

2003-01-01

The model of a two-dimensional fluid flow past a cylinder is a relatively simple problem with a strong impact in many applied fields, such as aerodynamics or chemical sciences, although most of the involved physical mechanisms are not yet well known. This paper analyzes the fluid flow past a cylinder in a laminar regime with Reynolds number, Re, around 200, where two vortices appear behind the cylinder, by using an appropriate time-dependent stream function and applying non-linear dynamics techniques. The goal of the paper is to analyze under which circumstances the chaoticity in the wake of the cylinder might be modified, or even suppressed. And this has been achieved with the help of some indicators of the complexity of the trajectories for the cases of a rotating cylinder and an oscillating cylinder

76 FR 55736 - Safety Advisory: Unauthorized Marking of Compressed Gas Cylinders

Science.gov (United States)

2011-09-08

... certain of high- and low-pressure compressed gas cylinders, primarily fire extinguishers, by Atlas Fire...- pressure cylinders serviced by Atlas Fire Protection were marked and represented as requalified (visually... damage, serious personal injury, or death could result from the rupture of a cylinder. Cylinders not...

The Passive Neutron Enrichment Meter for Uranium Cylinder Assay

Energy Technology Data Exchange (ETDEWEB)

Miller, Karen A.; Menlove, Howard O.; Swinhoe, Martyn T.; Marlow, Johanna B. [Safeguards Science and Technology Group (N-1), Los Alamos National Laboratory, Los Alamos (United States)

2011-12-15

As fuel cycle technology becomes more prevalent around the world, international safeguards have become increasingly important in verifying that nuclear materials have not been diverted. Uranium enrichment technology is a critical pathway to nuclear weapons development, making safeguards of enrichment facilities especially important. Independently-verifiable material accountancy is a fundamental measure in detecting diversion of nuclear materials. This paper is about a new instrument for uranium cylinder assay for enrichment plant safeguards called the Passive Neutron Enrichment Meter (PNEM). The measurement objective is to simultaneously verify uranium mass and enrichment in Uf6 cylinders. It can be used with feed, product, and tails cylinders. Here, we consider the enrichment range up to 5% {sup 235}U. The concept is to use the Doubles-to-Singles count rate to give a measure of the {sup 235}U enrichment and the Singles count rate to provide a measure of the total uranium mass. The cadmium ratio is an additional signature for the enrichment that is especially useful for feed and tails cylinders. PNEM is a {sup 3}He-based system that consists of two portable detector pods. Uranium enrichment in UF{sub 6} cylinders is typically determined using a gamma-ray-based method that only samples a tiny volume of the cylinder's content and requires knowledge of the cylinder wall thickness. The PNEM approach has several advantages over gamma-ray-based methods including a deeper penetration depth into the cylinder, meaning it can be used with heterogeneous isotopic mixtures of UF{sub 6}. In this paper, we describe a Monte Carlo modelling study where we have examined the sensitivity of the system to systematic uncertainties such as the distribution of UF{sub 6} within the cylinder. We also compare characterization measurements of the PNEM prototype to the expected measurements calculated with Monte Carlo simulations.

Steady particulate flows in a horizontal rotating cylinder

Science.gov (United States)

Yamane, K.; Nakagawa, M.; Altobelli, S. A.; Tanaka, T.; Tsuji, Y.

1998-06-01

Results of discrete element method (DEM) simulation and magnetic resonance imaging (MRI) experiments are compared for monodisperse granular materials flowing in a half-filled horizontal rotating cylinder. Because opacity is not a problem for MRI, a long cylinder with an aspect ratio ˜7 was used and the flow in a thin transverse slice near the center was studied. The particles were mustard seeds and the ratio of cylinder diameter to particle diameter was approximately 50. The parameters compared were dynamic angle of repose, velocity field in a plane perpendicular to the cylinder axis, and velocity fluctuations at rotation rates up to 30 rpm. The agreement between DEM and MRI was good when the friction coefficient and nonsphericity were adjusted in the simulation for the best fit.

Acoustic emission from fiber reinforced plastic damaged hoop wrapped cylinders

Energy Technology Data Exchange (ETDEWEB)

Akhtar, A.; Kung, D.; Westbrook, D.R.

2000-03-01

Metal lined continuous fiber reinforced plastic (FRP) hoop wrapped cylinders with axial cuts to the FRP were modeled mathematically and tested experimentally. Steel lined and aluminum alloy lined glass FRP vessels were subjected to acoustic emission tests (AE) and hydraulic burst tests. The burst pressure decreased monotonically with the length of the axial cut. Acoustic emission increased initially with a decrease in burst pressure, and attained a maximum at an intermediate level of damage to the FRP. However, acoustic emission decreased when the level of damage was higher and the burst pressure was lower. Implications of the findings are discussed in the context of the search for an acoustic emission test method to inspect periodically the vessels used for the storage of compressed gaseous fuels on natural gas vehicles (NGV) and hydrogen vehicles.

Proximity functions for general right cylinders

International Nuclear Information System (INIS)

Kellerer, A.M.

1981-01-01

Distributions of distances between pairs of points within geometrical objects, or the closely related proximity functions and geometric reduction factors, have applications to dosimetric and microdosimetric calculations. For convex bodies these functions are linked to the chord-length distributions that result from random intersections by straight lines. A synopsis of the most important relations is given. The proximity functions and related functions are derived for right cylinders with arbitrary cross sections. The solution utilizes the fact that the squares of the distances between two random points are sums of independently distributed squares of distances parallel and perpendicular to the axis of the cylinder. Analogous formulas are derived for the proximity functions or geometric reduction factors for a cylinder relative to a point. This requires only a minor modification of the solution

ROBUST CYLINDER FITTING IN THREE-DIMENSIONAL POINT CLOUD DATA

Directory of Open Access Journals (Sweden)

A. Nurunnabi

2017-05-01

Full Text Available This paper investigates the problems of cylinder fitting in laser scanning three-dimensional Point Cloud Data (PCD. Most existing methods require full cylinder data, do not study the presence of outliers, and are not statistically robust. But especially mobile laser scanning often has incomplete data, as street poles for example are only scanned from the road. Moreover, existence of outliers is common. Outliers may occur as random or systematic errors, and may be scattered and/or clustered. In this paper, we present a statistically robust cylinder fitting algorithm for PCD that combines Robust Principal Component Analysis (RPCA with robust regression. Robust principal components as obtained by RPCA allow estimating cylinder directions more accurately, and an existing efficient circle fitting algorithm following robust regression principles, properly fit cylinder. We demonstrate the performance of the proposed method on artificial and real PCD. Results show that the proposed method provides more accurate and robust results: (i in the presence of noise and high percentage of outliers, (ii for incomplete as well as complete data, (iii for small and large number of points, and (iv for different sizes of radius. On 1000 simulated quarter cylinders of 1m radius with 10% outliers a PCA based method fit cylinders with a radius of on average 3.63 meter (m; the proposed method on the other hand fit cylinders of on average 1.02 m radius. The algorithm has potential in applications such as fitting cylindrical (e.g., light and traffic poles, diameter at breast height estimation for trees, and building and bridge information modelling.

An experiments and characteristics analysis of the sealless cylinder

International Nuclear Information System (INIS)

Kim, Young Cheol; Kim, Dong Soo; Bae, Sang Kyu; Kim, Sung Jong

2004-01-01

This paper shows a performance analysis for conical type sealless cylinders and rod bearings. The pistons without seal have partly cylindrical and conical shapes. 2 dimensional Reynolds equation and FD(Finite Differential) numerical techniques are utilized for the performance analysis. The relationship among self-centering forces and leakage flows are investigated. Also, optimal design values for a sealless cylinder are presented. A prototype of sealless cylinder which had rod bearing with four pockets, five pockets, and six pockets was manufactured respectively. Leakage flow test is conducted to evaluate performance of piston and rod bearing in sealless cylinder

Magnetic susceptibility in the edged topological disordered nanoscopic cylinder

International Nuclear Information System (INIS)

Faizabadi, Edris; Omidi, Mahboubeh

2011-01-01

The effects of edged topological disorder on magnetic susceptibility are investigated in a nanoscopic cylinder threaded by a magnetic flux. Persistent current versus even or odd number of electrons shows different signs in ordered and disordered cylinders and also in short or long ones. In addition, temperature-averaged susceptibility has only diamagnetic signs in strong regimes and it is associated with paramagnetic signs in ordered and weak disordered ones. Besides, in an edged topological disordered cylinder, the temperature-averaged susceptibility decreases by raising the temperature somewhat and then increasing initiates and finally at high temperature tends to zero as the ordered one. - Research highlights: → Magnetic susceptibility in one-dimensional topological disordered quantum ring. → Edged topological disorder effect on magnetic susceptibility in nanoscopic cylinder. → Edged topological disorder effect on temperature-averaged susceptibility in cylinder.

Dynamical instability of a charged gaseous cylinder

Science.gov (United States)

Sharif, M.; Mumtaz, Saadia

2017-10-01

In this paper, we discuss dynamical instability of a charged dissipative cylinder under radial oscillations. For this purpose, we follow the Eulerian and Lagrangian approaches to evaluate linearized perturbed equation of motion. We formulate perturbed pressure in terms of adiabatic index by applying the conservation of baryon numbers. A variational principle is established to determine characteristic frequencies of oscillation which define stability criteria for a gaseous cylinder. We compute the ranges of radii as well as adiabatic index for both charged and uncharged cases in Newtonian and post-Newtonian limits. We conclude that dynamical instability occurs in the presence of charge if the gaseous cylinder contracts to the radius R*.

Prediction model of velocity field around circular cylinder over various Reynolds numbers by fusion convolutional neural networks based on pressure on the cylinder

Science.gov (United States)

Jin, Xiaowei; Cheng, Peng; Chen, Wen-Li; Li, Hui

2018-04-01

A data-driven model is proposed for the prediction of the velocity field around a cylinder by fusion convolutional neural networks (CNNs) using measurements of the pressure field on the cylinder. The model is based on the close relationship between the Reynolds stresses in the wake, the wake formation length, and the base pressure. Numerical simulations of flow around a cylinder at various Reynolds numbers are carried out to establish a dataset capturing the effect of the Reynolds number on various flow properties. The time series of pressure fluctuations on the cylinder is converted into a grid-like spatial-temporal topology to be handled as the input of a CNN. A CNN architecture composed of a fusion of paths with and without a pooling layer is designed. This architecture can capture both accurate spatial-temporal information and the features that are invariant of small translations in the temporal dimension of pressure fluctuations on the cylinder. The CNN is trained using the computational fluid dynamics (CFD) dataset to establish the mapping relationship between the pressure fluctuations on the cylinder and the velocity field around the cylinder. Adam (adaptive moment estimation), an efficient method for processing large-scale and high-dimensional machine learning problems, is employed to implement the optimization algorithm. The trained model is then tested over various Reynolds numbers. The predictions of this model are found to agree well with the CFD results, and the data-driven model successfully learns the underlying flow regimes, i.e., the relationship between wake structure and pressure experienced on the surface of a cylinder is well established.

Mechanical Integrity of Copper Canister Lid and Cylinder. Sensitivity study

International Nuclear Information System (INIS)

Karlsson, Marianne

2002-08-01

This report is part of a study of the mechanical integrity of canisters used for disposal of nuclear fuel waste. The overall objective is to determine and ensure the static and long-term strength of the copper canister lid and cylinder casing. The canisters used for disposal nuclear fuel waste of type BWR consists of an inner part (insert) of ductile cast iron and an outer part of copper. The copper canister is to provide a sealed barrier between the contents of the canister and the surroundings. The study in this report complements the finite element analyses performed in an earlier study. The analyses aim to evaluate the sensitivity of the canister to tolerances regarding the gap between the copper cylinder and the cast iron insert. Since great uncertainties regarding the material's long term creep properties prevail, analyses are also performed to evaluate the effect of different creep data on the resulting strain and stress state. The report analyses the mechanical response of the lid and flange of the copper canister when subjected to loads caused by pressure from swelling bentonite and from groundwater at a depth of 500 meter. The loads acting on the canister are somewhat uncertain and the cases investigated in this report are possible cases. Load cases analysed are: Pressure 15 MPa uniformly distributed on lid and 5 MPa uniformly distributed on cylinder; Pressure 5 MPa uniformly distributed on lid and 15 MPa uniformly distributed on cylinder; Pressure 20 MPa uniformly distributed on lid and cylinder; and Side pressures 10 MPa and 20 MPa uniformly distributed on part of the cylinder. Creep analyses are performed for two of the load cases. For all considered designs high principal stresses appear on the outside of the copper cylinder in the region from the weld down to the level of the lid lower edge. Altering the gap between lid and cylinder and/or between cylinder and insert only marginally affects the resulting stress state. Fitting the lid in the cylinder

Evaluation of Concrete Cylinder Tests Using Finite Elements

DEFF Research Database (Denmark)

Saabye Ottosen, Niels

1984-01-01

Nonlinear axisymmetric finite element analyses are performed on the uniaxial compressive test of concrete cylinders. The models include thick steel loading plates, and cylinders with height‐to‐diameter ratios (h/d) ranging from 1‐3 are treated. A simple constitutive model of the concrete is emplo......Nonlinear axisymmetric finite element analyses are performed on the uniaxial compressive test of concrete cylinders. The models include thick steel loading plates, and cylinders with height‐to‐diameter ratios (h/d) ranging from 1‐3 are treated. A simple constitutive model of the concrete...... uniaxial strength the use of geometrically matched loading plates seems to be advantageous. Finally, it is observed that for variations of the element size within limits otherwise required to obtain a realistic analysis, the results are insensitive to the element size....

SU-G-206-06: Analytic Dose Function for CT Scans in Infinite Cylinders as a Function of Scan Length and Cylinder Radius

Energy Technology Data Exchange (ETDEWEB)

Bakalyar, D [Henry Ford Health System, Detroit, MI (United States); Feng, W [New York Presbyterian Hospital, Tenafly, NJ (United States); McKenney, S [Children’s National Medical Center, Washington, DC (United States)

2016-06-15

Purpose: The radiation dose absorbed at a particular radius ρ within the central plane of a long cylinder following a CT scan is a function of the length of the scan L and the cylinder radius R along with kVp and cylinder composition. An analytic function was created that that not only expresses these dependencies but is integrable in closed form over the area of the central plane. This feature facilitates explicit calculation of the planar average dose. The “approach to equilibrium” h(L) discussed in the TG111 report is seamlessly included in this function. Methods: For a cylindrically symmetric radiation field, Monte Carlo calculations were performed to compute the dose distribution to long polyethylene cylinders for scans of varying L for cylinders ranging in radius from 5 to 20 cm. The function was developed from the resultant Monte Carlo data. In addition, the function was successfully fit to data taken from measurements on the 30 cm diameter ICRU/TG200 phantom using a real-time dosimeter. Results: Symmetry and continuity dictate a local extremum at the center which is a minimum for the larger sizes. There are competing effects as the beam penetrates the cylinder from the outside: attenuation, resulting in a decrease; scatter, abruptly increasing at the circumference. This competition may result in an absolute maximum between the center and outer edge leading to a “gull wing” shape for the radial dependence. For the smallest cylinders, scatter may dominate to the extent that there is an absolute maximum at the center. Conclusion: An integrable, analytic function has been developed that provides the radial dependency of dose for the central plane of a scan of length L for cylinders of varying diameter. Equivalently, we have developed h(L,R,ρ).

A constant-density Gurney approach to the Cylinder test

Energy Technology Data Exchange (ETDEWEB)

Reaugh, John E.; Souers, P. Clark [Energetic Materials Center, Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

2004-04-01

The previous analysis of the Cylinder test required the treatment of different wall thicknesses and wall materials separately. To fix this, the Gurney analysis is used, but this results in low values for full-wall standard, ideal explosives relative to CHEETAH analyses. A new constant metal-density model is suggested, which takes account of the thinning metal wall as the cylinder expands. With this model, the inner radius of the metal cylinder moves faster than the measured outer radius. Additional small corrections occur in all cylinders because of energy trapped in the copper walls. Also, the half-wall cylinders have a small correction because the relative volumes of the gas products are smaller at a given outside wall displacement. The Fabry-Perot and streak camera measurements are compared. The Fabry method is shown to equate to the constant density model. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

Financial feasibility of a log sort yard handling small-diameter logs: A preliminary study

Science.gov (United States)

Han-Sup Han; E. M. (Ted) Bilek; John (Rusty) Dramm; Dan Loeffler; Dave Calkin

2011-01-01

The value and use of the trees removed in fuel reduction thinning and restoration treatments could be enhanced if the wood were effectively evaluated and sorted for quality and highest value before delivery to the next manufacturing destination. This article summarizes a preliminary financial feasibility analysis of a log sort yard that would serve as a log market to...

Investigation on carbon nanomaterials: Coaxial CNT-cylinders and ...

Indian Academy of Sciences (India)

Wintec

carbon cylinders of CNT stacks have been formed directly inside the quartz tube. Another study is ... producing CNTs have been devised including electric arc evaporation ... process of coaxial carbon cylinder have already been de- scribed by ...

Adaptive individual-cylinder thermal state control using piston cooling for a GDCI engine

Science.gov (United States)

Roth, Gregory T; Husted, Harry L; Sellnau, Mark C

2015-04-07

A system for a multi-cylinder compression ignition engine includes a plurality of nozzles, at least one nozzle per cylinder, with each nozzle configured to spray oil onto the bottom side of a piston of the engine to cool that piston. Independent control of the oil spray from the nozzles is provided on a cylinder-by-cylinder basis. A combustion parameter is determined for combustion in each cylinder of the engine, and control of the oil spray onto the piston in that cylinder is based on the value of the combustion parameter for combustion in that cylinder. A method for influencing combustion in a multi-cylinder engine, including determining a combustion parameter for combustion taking place in in a cylinder of the engine and controlling an oil spray targeted onto the bottom of a piston disposed in that cylinder is also presented.

Vortex shedding control of circular cylinder by perforated shroud in deep water

Directory of Open Access Journals (Sweden)

Ozkan Gokturk M.

2017-01-01

Full Text Available The aim of the present study is to control the vortex shedding downstream of a circular cylinder (inner cylinder by the existence of outer perforated cylinder concentrically located around the inner cylinder in deep water. The flow characteristics downstream of concentrically placed coupled cylinders were investigated quantitatively by the Particle Image Velocimetry (PIV technique. Diameter of the outer perforated cylinder and inner cylinder were kept constant as Do=100 mm and Di=50 mm. The depth-averaged free-stream velocity was also kept constant as U=100 mm/s which corresponded to the Reynolds number of ReDo=10,000 based on the outer cylinder diameter. Experiments were conducted for six porosities (β = 0.3, 0.4, 0.5, 0.6, 0.7 and 0.8 in order to show the effect of these parameters on the flow control. Maximum values of both Reynolds shear stress, and turbulence kinetic energy, significantly decreased with the existence of outer perforated cylinder and also, the location of peak magnitudes of turbulence statistics occurred at locations further downstream compared to the bare cylinder case. The most effective control was revealed for the porosity of β=0.7.

Vortex shedding control of circular cylinder by perforated shroud in deep water

Science.gov (United States)

Ozkan, Gokturk M.; Durhasan, Tahir; Pinar, Engin; Aksoy, Muhammed M.; Akilli, Huseyin; Sahin, Beşir

The aim of the present study is to control the vortex shedding downstream of a circular cylinder (inner cylinder) by the existence of outer perforated cylinder concentrically located around the inner cylinder in deep water. The flow characteristics downstream of concentrically placed coupled cylinders were investigated quantitatively by the Particle Image Velocimetry (PIV) technique. Diameter of the outer perforated cylinder and inner cylinder were kept constant as Do=100 mm and Di=50 mm. The depth-averaged free-stream velocity was also kept constant as U=100 mm/s which corresponded to the Reynolds number of ReDo=10,000 based on the outer cylinder diameter. Experiments were conducted for six porosities (β = 0.3, 0.4, 0.5, 0.6, 0.7 and 0.8) in order to show the effect of these parameters on the flow control. Maximum values of both Reynolds shear stress, and turbulence kinetic energy, significantly decreased with the existence of outer perforated cylinder and also, the location of peak magnitudes of turbulence statistics occurred at locations further downstream compared to the bare cylinder case. The most effective control was revealed for the porosity of β=0.7.

AFM tip-sample convolution effects for cylinder protrusions

Science.gov (United States)

Shen, Jian; Zhang, Dan; Zhang, Fei-Hu; Gan, Yang

2017-11-01

A thorough understanding about the AFM tip geometry dependent artifacts and tip-sample convolution effect is essential for reliable AFM topographic characterization and dimensional metrology. Using rigid sapphire cylinder protrusions (diameter: 2.25 μm, height: 575 nm) as the model system, a systematic and quantitative study about the imaging artifacts of four types of tips-two different pyramidal tips, one tetrahedral tip and one super sharp whisker tip-is carried out through comparing tip geometry dependent variations in AFM topography of cylinders and constructing the rigid tip-cylinder convolution models. We found that the imaging artifacts and the tip-sample convolution effect are critically related to the actual inclination of the working cantilever, the tip geometry, and the obstructive contacts between the working tip's planes/edges and the cylinder. Artifact-free images can only be obtained provided that all planes and edges of the working tip are steeper than the cylinder sidewalls. The findings reported here will contribute to reliable AFM characterization of surface features of micron or hundreds of nanometers in height that are frequently met in semiconductor, biology and materials fields.

Effect of Surface Coatings on Cylinders Exposed to Underwater Shock

Directory of Open Access Journals (Sweden)

Y.W. Kwon

1994-01-01

Full Text Available The response of a coated cylinder (metallic cylinder coated with a rubber material subjected to an underwater explosion is analyzed numerically. The dynamic response of the coated cylinder appears to be adversely affected when impacted by an underwater shock wave under certain conditions of geometry and material properties of the coating. When adversely affected, significant deviations in values of axial stress, hoop stress, and strain are observed. The coated cylinder exhibits a larger deformation and higher internal energy in the metallic material. Rubber coatings appeared to inhibit energy dissipation from the metallic material to the surrounding water medium. A parametric study of various coatings was performed on both aluminum and steel cylinders. The adverse effect of the coating decreased when the stiffness of the rubber layer increased, indicating the existence of a threshold value. The results of this study indicate that the stiffness of the coating is a critical factor to the shock hardening of the coated cylinder.

49 CFR 1242.67 - Switch crews; controlling operations; yard and terminal clerical; locomotive fuel; electric power...

Science.gov (United States)

2010-10-01

... 49 Transportation 9 2010-10-01 2010-10-01 false Switch crews; controlling operations; yard and terminal clerical; locomotive fuel; electric power purchased/produced for motive power; operating switches... SERVICE FOR RAILROADS 1 Operating Expenses-Transportation § 1242.67 Switch crews; controlling operations...

Effect of High Porosity Screen on the Near Wake of a Circular Cylinder

Directory of Open Access Journals (Sweden)

Sahin B.

2013-04-01

Full Text Available The change in flow characteristics downstream of a circular cylinder (inner cylinder surrounded by a permeable cylinder (outer cylinder made of a high porosity screen was investigated in shallow water using Particle Image Velocimetry (PIV technique. The diameter of the inner cylinder, outer cylinder and the water height were kept constant during the experiments as d = 50 mm, D = 100 mm and hw = 50 mm, respectively. The depth-averaged free stream velocity was also kept constant as U = 180 mm/s which corresponded to a Reynolds number of Red = 9000 based on the inner cylinder diameter. It was shown that the outer permeable cylinder had a substantialeffect on the vortex formation and consequent vortex shedding downstream of the circular cylinder, especially in the near wake. The time averaged vorticity layers, streamlines and velocity vector field depict that the location of the interaction of vortices considerably changed by the presence of the outer cylinder. Turbulent statistics clearly demonstrated that in comparison to the natural cylinder, turbulent kinetic energy and Reynolds stresses decreased remarkably downstream of the inner cylinder. Moreover, spectra of streamwise velocity fluctuations showed that the vortex shedding frequency significantly reduced compared to the natural cylinder case.

49 CFR 180.205 - General requirements for requalification of specification cylinders.

Science.gov (United States)

2010-10-01

... each cylinder tested, except that for an analog device, interpolation to 1/2 of the marked gauge... for training persons who requalify cylinders using the volumetric expansion test method. (h) Cylinder...

Plane Wall Effect of Flow around Two Circular Cylinders in Tandem Arrangement

Directory of Open Access Journals (Sweden)

Triyogi Yuwono,

2011-02-01

Full Text Available The flow characteristic around two circular cylinders in tandem arrangement located near a plane wall were investigated experimentally in a uniform flow at a Reynolds Number of 5.3 x 104. The center to center spacing between the two cylinders relative to the cylinder diameter was constantly maintained at P/D = 1.5. The pressure distributions along the surface of the cylinder and the plane wall were measured by varying the gap-to-diameter of cylinder ratio (G/D in the range of 0 < G/D < 0.467. Surface oil-film techniques were used to investigate the flow patterns on the cylinder. The result showed that for upstream cylinder, in the gap-to-diameter ratio G/D < /D, there is no stagnation point at front side of the upstream cylinder; it is gradually raised as the gap increase. For the downstream cylinder, a peak on the lower side of the front side of the cylinder is apparent in each of the pressure distributions. This peak represents the reattachment of shear layer that separates from lower side of the upstream cylinder. The reattachment point tends to move forward close to the angular position of  = 0o as the gap ratio increase. The shear layer bifurcates into two shear layers. One shear layer continues in the downstream direction, and the other shear layer flows in the upstream direction.

Experimental study on flow past a rotationally oscillating cylinder

Science.gov (United States)

Gao, Yang-yang; Yin, Chang-shan; Yang, Kang; Zhao, Xi-zeng; Tan, Soon Keat

2017-08-01

A series of experiments was carried out to study the flow behaviour behind a rotationally oscillating cylinder at a low Reynolds number (Re=300) placed in a recirculation water channel. A stepper motor was used to rotate the cylinder clockwise- and- counterclockwise about its longitudinal axis at selected frequencies. The particle image velocimetry (PIV) technique was used to capture the flow field behind a rotationally oscillating cylinder. Instantaneous and timeaveraged flow fields such as the vorticity contours, streamline topologies and velocity distributions were analyzed. The effects of four rotation angle and frequency ratios F r ( F r= f n/ f v, the ratio of the forcing frequency f n to the natural vortex shedding frequency f v) on the wake in the lee of a rotationally oscillating cylinder were also examined. The significant wake modification was observed when the cylinder undergoes clockwise-and-counterclockwise motion with amplitude of π, especially in the range of 0.6≤ F r≤1.0.

Adaptive individual-cylinder thermal state control using intake air heating for a GDCI engine

Science.gov (United States)

Roth, Gregory T.; Sellnau, Mark C.

2016-08-09

A system for a multi-cylinder compression ignition engine includes a plurality of heaters, at least one heater per cylinder, with each heater configured to heat air introduced into a cylinder. Independent control of the heaters is provided on a cylinder-by-cylinder basis. A combustion parameter is determined for combustion in each cylinder of the engine, and control of the heater for that cylinder is based on the value of the combustion parameter for combustion in that cylinder. A method for influencing combustion in a multi-cylinder compression ignition engine, including determining a combustion parameter for combustion taking place in a cylinder of the engine and controlling a heater configured to heat air introduced into that cylinder, is also provided.

Cracked lifting lug welds on ten-ton UF{sub 6} cylinders

Energy Technology Data Exchange (ETDEWEB)

Dorning, R.E. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

1991-12-31

Ten-ton, Type 48X, UF{sub 6} cylinders are used at the Portsmouth Gaseous Diffusion Plant to withdraw enriched uranium hexafluoride from the cascade, transfer enriched uranium hexafluoride to customer cylinders, and feed enriched product to the cascade. To accomplish these activities, the cylinders are lifted by cranes and straddle carriers which engage the cylinder lifting lugs. In August of 1988, weld cracks on two lifting lugs were discovered during preparation to lift a cylinder. The cylinder was rejected and tagged out, and an investigating committee formed to determine the cause of cracking and recommend remedial actions. Further investigation revealed the problem may be general to this class of cylinder in this use cycle. This paper discusses the actions taken at the Portsmouth site to deal with the cracked lifting lug weld problem. The actions include inspection activities, interim corrective actions, metallurgical evaluation of cracked welds, weld repairs, and current monitoring/inspection program.

Guided Circumferential Waves in Layered Poroelastic Cylinders

Directory of Open Access Journals (Sweden)

Shah S.A.

2016-12-01

Full Text Available The present paper investigates the propagation of time harmonic circumferential waves in a two-dimensional hollow poroelastic cylinder with an inner shaft (shaft-bearing assembly. The hollow poroelastic cylinder and inner shaft are assumed to be infinite in axial direction. The outer surface of the cylinder is stress free and at the interface, between the inner shaft and the outer cylinder, it is assumed to be free sliding and the interfacial shear stresses are zero, also the normal stress and radial displacements are continuous. The frequency equation of guided circumferential waves for a permeable and an impermeable surface is obtained. When the angular wave number vanish the frequency equation of guided circumferential waves for a permeable and an impermeable surface degenerates and the dilatational and shear waves are uncoupled. Shear waves are independent of the nature of surface. The frequency equation of a permeable and an impermeable surface for bore-piston assembly is obtained as a particular case of the model under consideration when the outer radius of the hollow poroelastic cylinder tends to infinity. Results of previous studies are obtained as a particular case of the present study. Nondimensional frequency as a function of wave number is presented graphically for two types of models and discussed. Numerical results show that, in general, the first modes are linear for permeable and impermeable surfaces and the frequency of a permeable surface is more than that of an impermeable surface.

Convective heat transfer from a heated elliptic cylinder at uniform wall temperature

Energy Technology Data Exchange (ETDEWEB)

Kaprawi, S.; Santoso, Dyos [Mechanical Department of Sriwijaya University, Jl. Raya Palembang-Prabumulih Km. 32 Inderalaya 50062 Ogan Ilir (Indonesia)

2013-07-01

This study is carried out to analyse the convective heat transfer from a circular and an elliptic cylinders to air. Both circular and elliptic cylinders have the same cross section. The aspect ratio of cylinders range 0-1 are studied. The implicit scheme of the finite difference is applied to obtain the discretized equations of hydrodynamic and thermal problem. The Choleski method is used to solve the discretized hydrodynamic equation and the iteration method is applied to solve the discretized thermal equation. The circular cylinder has the aspect ratio equal to unity while the elliptical cylinder has the aspect ratio less than unity by reducing the minor axis and increasing the major axis to obtain the same cross section as circular cylinder. The results of the calculations show that the skin friction change significantly, but in contrast with the elliptical cylinders have greater convection heat transfer than that of circular cylinder. Some results of calculations are compared to the analytical solutions given by the previous authors.

Cylinder gauge measurement using a position sensitive detector

International Nuclear Information System (INIS)

St John, W. Doyle

2007-01-01

A position sensitive detector (PSD) has been used to determine the diameter of cylindrical pins based on the shift in a laser beam's centroid. The centroid of the light beam is defined here as the weighted average of position by the local intensity. A shift can be observed in the centroid of an otherwise axially symmetric light beam, which is partially obstructed. Additionally, the maximum shift in the centroid is a unique function of the obstructing cylinder diameter. Thus to determine the cylinder diameter, one only needs to detect this maximum shift as the cylinder is swept across the beam

Effect of Resistance Tube Exercises on Kicking Accuracy, Vertical Jump and 40-Yard Technical Test in Competitive Football Players – An Experimental Study

Directory of Open Access Journals (Sweden)

Tirumala Alekhya

2014-09-01

Full Text Available Purpose. Kicking, jumping and agility are important skills in football. These activities require adequate lower limb strength, which can be enhanced with resistance training. The objective of the study was to evaluate the effect of resistance tube exercises on kicking accuracy, vertical jump performance and 40-yard technical test results in competitive football players. Methods. The study involved 23 competitive football players (11 males, 12 females aged from 18-20 years recruited from three different universities in Belgaum, Karnataka, India. Back heel kick accuracy, vertical jump height and 40-yard technical test time were evaluated before and after a 2-week resistance tube exercise program. Results. Significant improvements in post-intervention kicking accuracy were found when males and females were treated as a single group (p = 0.01. Vertical jump height also showed a highly significant post-intervention improvement in the males and for the combined group of males and females (p = 0.001. The 40-yard technical test values significantly improved in the females and in the combined results for males and females (p = 0.001. Conclusions. The two-week resistance tube exercise program was found to have an effect on kicking accuracy, vertical jump height and 40-yard technical test performance in competitive football players. Resistance tube exercises can thus be included as a component of a regular strength training program for such athletes.

Development of new systems of natural gas storage in vehicles; Desenvolvimento de novos sistemas de armazenamento de gas natural em veiculos automotivos

Energy Technology Data Exchange (ETDEWEB)

Souza, Jose R.; Rojas, Leopoldo O.A.; Silva, Claudio F. da; Dantas, Jose H.A. [Centro de Tecnologias do Gas (CTGAS), Natal, RN (Brazil); Moraes, Caetano [Instituto Nacional de Tecnologia (INT), Rio de Janeiro, RJ (Brazil); Scudelari, Ada Cristina; Villena, John Neira [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Freire, Luiz G. de M. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

2004-07-01

The conversion of gasoline to natural gas powered vehicles faces some problems that limit its market expansion, so as the expensive costs inherent to the conversion, low autonomy and the reduction of the available trunk space. Thus, this research focuses on the adsorbed natural gas technology. Therefore three major items were analyzed: several porous materials so as to store the NG in lower pressure, without a drastic diminishing of capacity storage; new reservoir geometries, to optimize the trunk available space and the Brazilian legislation in order to determine the possibility of using cylinders made of alternative materials looking for a weight reduction. From the analysis of the Brazilian standards, we can conclude that there is a need for standardizing the use alternative NGV alternative cylinders, for example, the composite reservoir. The adsorption study over activated carbons resulted in an increased NG storage capacity when compare with compressed gas storage at the same operation conditions, but it is still far from the GNC maximum storage capacity and commercial application. For the reservoir structural modeling, three different geometries were selected and analyzed. (author)

Experimental and finite element prediction of bursting pressure in compound cylinders

International Nuclear Information System (INIS)

Majzoobi, G.H.; Farrahi, G.H.; Pipelzadeh, M.K.; Akbari, A.

2004-01-01

Aluminium cylinders with a constant ratio of outer to inner radii, k=2.2, with different diametral interferences and various shrinkage radii were subjected to bursting and autofrettage pressures. Numerical simulations of the compound cylinders were also performed using the finite element code, NISA. The results can predict the optimum shrinkage radius to a reasonable accuracy with the use of finite element analysis. This radius corresponds to the situation when the maximum von-Mises stress at the internal radii of both the inner and outer cylinders become equal. It was shown that the maximum von-Mises stress across the wall of the cylinder is at the minimum at this shrinkage radius. The optimum diametral interference was found to be that which sufficiently brought the contact surface of the inner and outer cylinders to the point of yielding. Should the shrinkage pressure exceed the elastic limit, the pressure capacity of the cylinder will not be improved. The numerical and experimental results show that autofrettage had no effect on the bursting pressure of the thick-walled compound cylinder for the material tested

PIV Measurements of He II Counterflow Around a Cylinder

International Nuclear Information System (INIS)

Fuzier, S.; Van Stiver, S. W.; Zhang, T.

2006-01-01

The induced flow field of counterflow He II across a circular cylinder has been quantitatively studied using the particle image velocimetry (PIV) technique. Two different size cylinders (6.35 mm and 2 mm in diameter) were used and placed in a 20 mm wide rectangular channel. In these experiments, large-scale eddy motion generated by the He II counterflow was observed both in front of and behind the cylinder, an effect which has no analogue in classical fluids

Bursting pressure of autofrettaged cylinders with inclined external cracks

International Nuclear Information System (INIS)

Seifi, Rahman; Babalhavaeji, Majid

2012-01-01

Autofrettaging a pressure vessel improves its pressure capacity. This is reliable if there isn’t any crack or other type of flaws. In this paper, the effects of external surface cracks on bursting pressure of autofrettaged cylinders are studied. It is observed that bursting pressure decreases considerably (up to 30%) due to external cracks in the cylinders without autofrettage. This reduction increases for high levels of the applied autofrettage. External axial cracks have more effects than inclined cracks. Comparing experimental and numerical results show that the numerical methods can acceptably predict the bursting pressure of the autofrettaged cracked cylinders. These predictions are valid when the fracture parameter (J-Integral) is calculated from the modified equation that takes into account the effects of residual stresses. - Highlights: ► Modified J-Integral can be used for study of autofrettaged cracked cylinders. ► External axial cracks reduce considerably the pressure capacity of cylinders. ► External circumferential cracks have not considerable effects on bursting pressure. ► Autofrettage has contrary effects on external crack in compared with internal crack.

A numerical simulation of VIV on a flexible circular cylinder

International Nuclear Information System (INIS)

Xie Fangfang; Deng Jian; Zheng Yao; Xiao Qing

2012-01-01

In this paper, numerical simulations of a flexible circular cylinder subjected to a vortex-induced vibration (VIV) are conducted. The Reynolds number for simulations is fixed at 1000. The finite volume method is applied for modeling fluid flow with the moving meshes feature. The dynamic response of a flexible cylinder fixed at both ends is modeled by the Euler–Bernoulli beam theory. The comparison between two-dimensional (2D) simulations and 3D simulations for the flexible cylinder shows that the maximum response amplitude of the cross-flow oscillation is about 0.57D for 2D rigid cylinders (modeled by a spring–damper–mass model) and 1.03D for flexible cylinders, respectively. The results from 3D simulations are closer to previous experimental results. Furthermore, the results obtained with various frequency ratios show that different wake patterns exist according to the frequency ratio, such as 2S mode, 2P mode and some more complicated modes. The wake pattern is different at various sections along the cylinder length, due to the fact that the two ends of the beam are fixed. The vibration of the flexible cylinder can also greatly alter the three dimensionality in the wake, which is our research in future work, especially in the transition region for Reynolds number ranging from 170 to 300. (paper)

Experimental investigation and exergy analysis on thermal storage integrated micro-cogeneration system

International Nuclear Information System (INIS)

Johar, Dheeraj Kishor; Sharma, Dilip; Soni, Shyam Lal; Gupta, Pradeep K.; Goyal, Rahul

2017-01-01

Highlights: • Energy Storage System is integrated with Micro cogeneration system. • Erythritol is used as Phase Change Material. • Maximum energy saved is 15.2%. • Maximum exergy saved is 4.22%. • Combined systems are feasible to increase energy and exergy efficiency. - Abstract: This paper describes the performance of thermal storage integrated micro-cogeneration system based on single cylinder diesel engine. In addition to electricity generated from genset, waste heat from hot exhaust of diesel engine was used to heat water in a double pipe heat exchanger of 67.70 cm length with inside tube diameter of 3.81 cm and outside tube diameter of 5.08 cm. Additionally, a latent heat thermal energy storage system was also integrated with this cogeneration system. A shell and tube type heat exchanger of 346 mm diameter and 420 mm height with 45 tubes of 18 mm diameter each was designed and fabricated, to store thermal energy, in which Erythritol (C_4H_1_0O_4) was used as phase changing material. The test results show that micro capacity (4.4 kW), stationary, single cylinder, diesel engine can be successfully utilized to simultaneously produce power as well as heating, and to also store thermal energy. Slight decrease in engine performance was observed when double pipe heat exchanger and latent heat thermal energy storage system was integrated with engine but the amount of energy which could be recovered was significant. Maximum percentage of energy saved was obtained at a load of 3.6 kW and was 15.2%.

Surface flaw in a thermally shocked hollow cylinder

International Nuclear Information System (INIS)

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

1975-01-01

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

Response of Buried Vertically Oriented Cylinders to Dynamic Loading,

Science.gov (United States)

1980-06-01

BALSARA • , . / ,, _,-, -. 1i S ,LESPONSE OF BURIED VERTICALLY 9RIENTED CYLINDERS 𔃺 .-TO DINAMIC LOADING_ 9AYLE E. LRTOrwW&-N JIIMY P./BALSARA Nk...1.7, 2,8, and 4.0 inches). The end caps for the cylinders consisted of a steel shell filled with high- strength concrete; however, the end caps were...not designed to be test articles. The average concrete compressive strength of the cylinders on test day was 44.0 MPa (6,380 psi). The three DEOT

Advanced engine management of individual cylinders for control of exhaust species

Science.gov (United States)

Graves, Ronald L [Knoxville, TN; West, Brian H [Knoxville, TN; Huff, Shean P [Knoxville, TN; Parks, II, James E

2008-12-30

A method and system controls engine-out exhaust species of a combustion engine having a plurality of cylinders. The method typically includes various combinations of steps such as controlling combustion parameters in individual cylinders, grouping the individual cylinders into a lean set and a rich set of one or more cylinders, combusting the lean set in a lean combustion parameter condition having a lean air:fuel equivalence ratio, combusting the rich set in a rich combustion parameter condition having a rich air:fuel equivalence ratio, and adjusting the lean set and the rich set of one or more cylinders to generate net-lean combustion. The exhaust species may have elevated concentrations of hydrogen and oxygen.

Extensive optimisation analyses of the piping of two large underground gas storage ariel compressors

NARCIS (Netherlands)

Eijk, A.; Korst, H.J.C.; Ploumen, G.; Heyer, D.

2007-01-01

Two large identical 6-cylinder Ariel JGB/6 compressors of each 7.5 Mw, are used for the underground gas storage (UGS) plant of Essent in Epe, Germany. The compressors can be operated at a wide range of operating conditions, e.g. variable suction and discharge pressures, 2-stage mode during gas

Transient thermal stress problem for a circumferentially cracked hollow cylinder

Science.gov (United States)

Nied, H. F.; Erdogan, F.

1982-01-01

The transient thermal stress problem for a hollow elasticity cylinder containing an internal circumferential edge crack is considered. It is assumed that the problem is axisymmetric with regard to the crack geometry and the loading, and that the inertia effects are negligible. The problem is solved for a cylinder which is suddenly cooled from inside. First the transient temperature and stress distributions in an uncracked cylinder are calculated. By using the equal and opposite of this thermal stress as the crack surface traction in the isothermal cylinder the crack problem is then solved and the stress intensity factor is calculated. The numerical results are obtained as a function of the Fourier number tD/b(2) representing the time for various inner-to-outer radius ratios and relative crack depths, where D and b are respectively the coefficient of diffusivity and the outer radius of the cylinder.

Electromagnetic Invisibility of Elliptic Cylinder Cloaks

International Nuclear Information System (INIS)

Kan, Yao; Chao, Li; Fang, Li

2008-01-01

Structures with unique electromagnetic properties are designed based on the approach of spatial coordinate transformations of Maxwell's equations. This approach is applied to scheme out invisible elliptic cylinder cloaks, which provide more feasibility for cloaking arbitrarily shaped objects. The transformation expressions for the anisotropic material parameters and the field distribution are derived. The cloaking performances of ideal and lossy elliptic cylinder cloaks are investigated by finite element simulations. It is found that the cloaking performance will degrade in the forward direction with increasing loss. (fundamental areas of phenomenology (including applications))

Cylinder wakes in flowing soap films

International Nuclear Information System (INIS)

Vorobieff, P.; Ecke, R.E.; Vorobieff, P.

1999-01-01

We present an experimental characterization of cylinder wakes in flowing soap films. From instantaneous velocity and thickness fields, we find the vortex-shedding frequency, mean-flow velocity, and mean-film thickness. Using the empirical relationship between the Reynolds and Strouhal numbers obtained for cylinder wakes in three dimensions, we estimate the effective soap-film viscosity and its dependence on film thickness. We also compare the decay of vorticity with that in a simple Rankine vortex model with a dissipative term to account for air drag. copyright 1999 The American Physical Society

Distribution, enrichment and accumulation of heavy metals in coastal sediments of Alang-Sosiya ship scrapping yard, India.

Science.gov (United States)

Reddy, M Srinivasa; Basha, Shaik; Sravan Kumar, V G; Joshi, H V; Ramachandraiah, G

2004-06-01

Since its inception in 1982, the Alang-Sosiya yard has become the largest ship scrapping works in the world. Several hundreds of ships arrive every year. The degree of heavy metal contamination has been studied in bulk and fine sediments from the intertidal zone of this ship scrapping yard, two stations, one on either side at 5 km distance and one reference station 60 km distance near Mahuva, towards the south. The samples have been subjected to a total digestion technique and analysed for elements: Cd, Co, Cu, Cr, Fe, Mn, Ni, Pb, Zn and Al, and %TOC. The absolute metal concentrations reflected variations in BF and FF sediment samples with organic matter content. Enrichment factors (EF) and geoaccumulation indices (Igeo) have been calculated and the relative contamination levels are assessed at these sites. At Alang-Sosiya, the enrichment of heavy metals has been observed to be relatively high.

Numerical simulation coupling with experimental study on the non-uniform of each cylinder gas exchange and working processes of a multi-cylinder gasoline engine under transient conditions

International Nuclear Information System (INIS)

Zhou, Feng; Fu, Jianqin; Shu, Jun; Liu, Jingping; Wang, Shuqian; Feng, Renhua

2016-01-01

Highlights: • An approach is presented to detect the CTCV of engine under transient conditions. • The range and influence factors of CTCV of engine performances were revealed. • The maximum relative deviation of IMEP in each cylinder is larger than ±30%. • There appears a symmetry relation between CTCV of RGF and excess air coefficient. - Abstract: Cylinder-to-cylinder variation is unavoidable in multi-cylinder engine and has a severe impact on engine performance. To explore the cylinder-to-cylinder variation of engine under transient conditions, a hybrid method of dynamic signal measurement coupling with gas dynamics and thermodynamics processes simulation is presented to detect the parameters of engine. Then, this method is applied to an automobile engine under road test conditions, and the continuous state and performance parameters of each cylinder were obtained from cycle to cycle. On this basis, the range and influence factors of non-uniform of engine performance parameters were analyzed. The results show that, under transient conditions, the relative deviation of excess air coefficient in each cylinder is within ±5%, which is mainly affected by intake average pressure in low to medium speed operating regions but influenced by exhaust pressure wave and residual gas fraction in high-speed and high-load operating regions. There appears a symmetry relation between the non-uniform of RGF and excess air coefficient. The relative deviation of indicated mean effective pressure in each cylinder depends largely on the gas exchange performance, including excess air coefficient and residual gas fraction, and the maximum is larger than ±30%.

Three-dimensional vortex flow near the endwall of a short cylinder in crossflow: Stepped-diameter circular cylinder

International Nuclear Information System (INIS)

Chen, S.B.; Sanitjai, S.; Ghosh, K.; Goldstein, R.J.

2012-01-01

The effect of geometry on the flow around a cylinder in crossflow is investigated in this study. Three different stepped-diameter circular cylinders (SDCC s) with varying step heights are used. Extensive flow visualization using the oil-lampblack and smoke-wire techniques and near wake velocity measurements using a hotwire anemometer reveal complex secondary flows on and around the SDCC. Six vortices are observed in the horseshoe vortex system near the cylinder–endwall junction and six additional vortices are found in the step-induced vortex system on the step surface. Based on these experimental results, new secondary flow models are proposed. The step-induced vortices separate from the step surface at both sides and move toward the endwall, washing down the sides of the top/bottom larger diameter cylinders and interact with the separated shear layer and horseshoe vortices. In this process, they modify the near wake flow significantly: they produce an increase in velocity near the endwall region (below the step) and a decrease in velocity near the mid-span region, even altering the oscillatory behavior of the wake. - Highlights: ► Extensive flow visualization for stepped-diameter circular cylinders in crossflow. ► Six vortices in the horseshoe vortex system near the base. ► Six additional step-induced vortices on the upstream symmetry plane of step surface. ► Power spectral analysis for u′ shows oscillatory nature of the wake.

Stresses from pressure, radial, and moment loads in cylinder-to-cylinder vessel by a finite plate method

International Nuclear Information System (INIS)

Brown, S.J.; Fox, M.E.

1977-08-01

A structural problem that has received continued interest and development over the last several decades is the determination of stresses in two normally intersecting cylindrical shells subjected to internal pressure and external loading. In nuclear pressure vessels the external loading of the vessel through the attachment is encountered in thermal interaction, seismic loading and various postulated rupture or failure mechanisms. A simple technique, the Finite Plate Method, (FPM) is presented to analyze stresses in cylinder-to-cylinder junctures. The approach uses shallow shell formulations and a three term series expansion plate formulation, which limits the range of applicability. It is felt that the value of the method is its accuracy, economy, and ease in modeling a structure which falls within the range of applicability. Another appealing feature of the method is that its simplistic approach of superposition of results permits an easy extension to include additional loads not treated. For those mechanical loadings not developed, it is felt that their effect can either be accounted for by the mechanisms discussed or by simple calculations. Generally, the stresses resulting from torsional or transverse shear are small compared to the loads discussed, however, these shear effects may be included. Finally, in the instance of thermal stress within the cylinder-to-cylinder structure, it has been shown in an unpublished study by Brown that the FPM yields very good results for the range of curvatures discussed

Torsional vibrations of infinite composite poroelastic cylinders | Shah ...

African Journals Online (AJOL)

... radius of composite poroelastic solid cylinder to the radius of the inner solid cylinder. Results of previous works are shown as special case of the present analysis. By ignoring liquid effects, the results of purely elastic solid are obtained. International Journal of Engineering, Science and Technology, Vol. 2, No. 6, 2010, pp.

Experimental investigation of thermal storage integrated micro trigeneration system

International Nuclear Information System (INIS)

Johar, Dheeraj Kishor; Sharma, Dilip; Soni, Shyam Lal; Goyal, Rahul; Gupta, Pradeep K.

2017-01-01

Highlights: • Energy Storage System is integrated with Micro trigeneration system. • Erythritol is used as Phase Change Material. • Maximum energy saved is 15.30%. • Combined systems are feasible to increase energy efficiency. - Abstract: In this study a 4.4 kW stationary compression ignition engine is coupled with a double pipe heat exchanger, vapour absorption refrigeration system and thermal energy storage system to achieve Trigeneration i.e. power, heating and cooling. A shell and tube type heat exchanger filled with erythritol is used to store thermal energy of engine exhaust. Various combinations of thermal energy storage system integrated micro-trigeneration were investigated and results related to performance and emissions are reported in this paper. The test results show that micro capacity (4.4 kW) stationary single cylinder diesel engine can be successfully modified to simultaneously produce power, heating and cooling and also store thermal energy.

An online ID identification system for liquefied-gas cylinder plant

Science.gov (United States)

He, Jin; Ding, Zhenwen; Han, Lei; Zhang, Hao

2017-11-01

An automatic ID identification system for gas cylinders' online production was developed based on the production conditions and requirements of the Technical Committee for Standardization of Gas Cylinders. A cylinder ID image acquisition system was designed to improve the image contrast of ID regions on gas cylinders against the background. Then the ID digits region was located by the CNN template matching algorithm. Following that, an adaptive threshold method based on the analysis of local average grey value and standard deviation was proposed to overcome defects of non-uniform background in the segmentation results. To improve the single digit identification accuracy, two BP neural networks were trained respectively for the identification of all digits and the easily confusable digits. If the single digit was classified as one of confusable digits by the former BP neural network, it was further tested by the later one, and the later result was taken as the final identification result of this single digit. At last, the majority voting was adopted to decide the final identification result for the 6-digit cylinder ID. The developed system was installed on a production line of a liquefied-petroleum-gas cylinder plant and worked in parallel with the existing weighing step on the line. Through the field test, the correct identification rate for single ID digit was 94.73%, and none of the tested 2000 cylinder ID was misclassified through the majority voting.

Frictional properties of lubrication greases with the addition of nickel nanoparticles in pneumatic cylinder

Science.gov (United States)

Chang, Ho; Lan, Chou-Wei; Guo, Jia-Bin

2011-12-01

This paper studies the influence of addition of 100 nm diameter nickel nano-particles on the friction properties of synthetic grease (Li base, VG100) in pneumatic cylinder. The friction force test of pneumatic cylinder equipment measures the frictional force between seal and cylinder bore in pneumatic cylinders. The lubricants with addition of nickel nano-particles were used for lubricating the contact interface between seal and cylinder bore. The friction force test equipment employ a load cell force sensor to measure the friction force between seals and cylinder bores. Results obtained from experimental tests are compared to determine the friction force between seals and cylinder bore in pneumatic cylinders. The study leads to the conclusion that the addition of nickel nano-particles to synthetic grease results in a decrease in friction force between seals and cylinder bores in pneumatic cylinder. This tribological behavior is closely related to the deposition of nano-particles on the rubbing surfaces

Final Confirmation Sampling and Analysis Report for the POL Yard, Sites SS-06 and ST-40, Wurtsmith AFB, Michigan

National Research Council Canada - National Science Library

1999-01-01

.... Wurtsmith AFBCA and AFCEE/ERT had no comments on the draft final report. This report represents the final contract deliverable for the AFCEE Extended Bioventing Project at the Wurtsmith AFB POL Yard...

A pneumatic cylinder driving polyhedron mobile mechanism

Science.gov (United States)

Ding, Wan; Kim, Sung-Chan; Yao, Yan-An

2012-03-01

A novel pneumatic cylinder driving polyhedron mobile mechanism is proposed in this paper. The mechanism is comprised of 5 tetrahedrons which includes a pneumatic cylinder in each edge. It locomotes by rolling and the rolling principle refers to the center of mass (CM) of the mechanism moved out of the supporting area and let it tip over through the controlling of the motion sequence of these cylinders. Firstly, the mathematical model is built to analysis the relation between the configuration and the CM of the mechanism. Then, a binary control strategy is developed to simplify and improve the control of this mobile mechanism. After that, dynamic simulation is performed to testify the analytical validity and feasibility of the rolling gaits. At last, a prototype is fabricated to achieve the rolling successfully to demonstrate the proposed concept.

The provision of clearances accuracy in piston - cylinder mating

Science.gov (United States)

Glukhov, V. I.; Shalay, V. V.

2017-08-01

The paper is aimed at increasing the quality of the pumping equipment in oil and gas industry. The main purpose of the study is to stabilize maximum values of productivity and durability of the pumping equipment based on the selective assembly of the cylinder-piston kinematic mating by optimization criterion. It is shown that the minimum clearance in the piston-cylinder mating is formed by maximum material dimensions. It is proved that maximum material dimensions are characterized by their own laws of distribution within the tolerance limits for the diameters of the cylinder internal mirror and the outer cylindrical surface of the piston. At that, their dispersion zones should be divided into size groups with a group tolerance equal to half the tolerance for the minimum clearance. The techniques for measuring the material dimensions - the smallest cylinder diameter and the largest piston diameter according to the envelope condition - are developed for sorting them into size groups. Reliable control of the dimensions precision ensures optimal minimum clearances of the piston-cylinder mating in all the size groups of the pumping equipment, necessary for increasing the equipment productivity and durability during the production, operation and repair processes.

Bursting pressure of autofrettaged cylinders with inclined external cracks

Energy Technology Data Exchange (ETDEWEB)

Seifi, Rahman, E-mail: rseifi@basu.ac.ir [Mechanical Engineering Department, Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of); Babalhavaeji, Majid [Mechanical Engineering Department, Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of)

2012-01-15

Autofrettaging a pressure vessel improves its pressure capacity. This is reliable if there isn't any crack or other type of flaws. In this paper, the effects of external surface cracks on bursting pressure of autofrettaged cylinders are studied. It is observed that bursting pressure decreases considerably (up to 30%) due to external cracks in the cylinders without autofrettage. This reduction increases for high levels of the applied autofrettage. External axial cracks have more effects than inclined cracks. Comparing experimental and numerical results show that the numerical methods can acceptably predict the bursting pressure of the autofrettaged cracked cylinders. These predictions are valid when the fracture parameter (J-Integral) is calculated from the modified equation that takes into account the effects of residual stresses. - Highlights: Black-Right-Pointing-Pointer Modified J-Integral can be used for study of autofrettaged cracked cylinders. Black-Right-Pointing-Pointer External axial cracks reduce considerably the pressure capacity of cylinders. Black-Right-Pointing-Pointer External circumferential cracks have not considerable effects on bursting pressure. Black-Right-Pointing-Pointer Autofrettage has contrary effects on external crack in compared with internal crack.

Formation of whispering gallery modes by scattering of an electromagnetic plane wave by two cylinders

Energy Technology Data Exchange (ETDEWEB)

Abramov, Arnold, E-mail: qulaser@gmail.com [Kuang-Chi Institute of Advanced Technology, Shenzhen, 518057 (China); Kostikov, Alexander [Donbass State Engineering Academy, 84303, Kramatorsk, Donetsk (Ukraine)

2017-03-26

We report the effect of scattering of electromagnetic plane waves by two cylinders on whispering gallery mode (WGM) formation in a cylinder. WGM can occur because of the presence of additional cylinder scatterers at specific location, while WGMs can only form in a single cylinder for specific cylinder radius and/or wavelength values, the matching accuracy required would be much greater than that required in our model for the additional cylinders locations. Analysis of the general solution to the problem showed that the effect can be explained by the interference of waves scattered by additional cylinders and incident on the main cylinder. - Highlights: • We consider scattering of electromagnetic plane waves by two cylinders. • WGMs occur because of the presence of additional cylinder at specific location. • The accuracy for the locations is much less than required for specific values of single cylinder. • The interference of waves scattered by additional cylinders and incident on the main is responsible for the effect.

Flow around a confined cylinder: LES and PIV study

Directory of Open Access Journals (Sweden)

Palkin Egor

2017-01-01

Full Text Available We study the flow over a cylinder placed between two parallel rigid walls using Large-eddy simulations and Particle Image Velocimetry. The Reynolds number based on the inflow velocity and diameter of the cylinder is 3750 corresponding to the subcritical regime with laminar separation. Three-dimensional visualization shows the presence of the horseshoe vortex system prior to the cylinder. The comparison of time-averaged velocity fields and fluctuations shows good agreement between simulations and experiments. Spectral analysis suggests the presence of low-frequency modulations of the recirculating bubble.

Collision Probabilities for Finite Cylinders and Cuboids

Energy Technology Data Exchange (ETDEWEB)

Carlvik, I

1967-05-15

Analytical formulae have been derived for the collision probabilities of homogeneous finite cylinders and cuboids. The formula for the finite cylinder contains double integrals, and the formula for the cuboid only single integrals. Collision probabilities have been calculated by means of the formulae and compared with values obtained by other authors. It was found that the calculations using the analytical formulae are much quicker and give higher accuracy than Monte Carlo calculations.

A numerical investigation of sub-wavelength resonances in polygonal metamaterial cylinders

DEFF Research Database (Denmark)

Arslanagic, Samel; Breinbjerg, Olav

2009-01-01

The sub-wavelength resonances, known to exist in metamaterial radiators and scatterers of circular cylindrical shape, are investigated with the aim of determining if these resonances also exist for polygonal cylinders and, if so, how they are affected by the shape of the polygon. To this end, a set...... of polygonal cylinders excited by a nearby electric line current is analyzed numerically and it is shown, through detailed analysis of the near-field distribution and radiation resistance, that these polygonal cylinders do indeed support sub-wavelength resonances similar to those of the circular cylinders...

Transient thermal stresses in circular cylinder under intermittently sudden heat generation

International Nuclear Information System (INIS)

Sugano, Y.; Saito, K.; Takeuti, Y.

1975-01-01

The thermal stresses associated with the transient temperature distribution arising in a circular cylinder under intermittently changing sudden heat generation over a finite band and with heat loss to a surrounding medium on the remainder of the cylinder surface are exactly analysed. For the first time the temperature field in a circular cylinder under sudden heat generation over a finite band of the cylinder surface is determined by combined use of Fourier cosine, Laplace transforms in axial position and time, respectively. Secondly it is assumed that the temperature fields in a circular cylinder subjected to heat generation Qsub(i) (i=0, 1, 2, ...) independently over a finite band are given by T 0 (r,z,t), T 1 (r,z,t), T 2 (r,z,t),... respectively. Tsub(i)(r,z,t) indicates the temperature field before the i-th heat generation Qsub(i). The thermal stresses associated with the temperature field described above are analysed by using the Hoyle stress functions. Numerical calculations are carried out for the extensive case of the ratio of the heat-generating length to the diameter of cylinder. It is found that the time in which the maximum stresses occur on the cylinder surface does not depend on the heat-generating length-to-diameter ratio

Stokes flow past a swarm of porous circular cylinders with Happel ...

Indian Academy of Sciences (India)

The problem of creeping flow past a swarm of porous circular cylinders with Happel and Kuwabara boundary conditions is investigated. The Brinkman equation for the flow inside the porous cylinder and the Stokes equation outside the porous cylinder in their stream function formulations are used. The force experienced by ...

Silo Storage Preconceptual Design

Energy Technology Data Exchange (ETDEWEB)

Stephanie L. Austad; Patrick W. Bragassa; Kevin M Croft; David S Ferguson; Scott C Gladson; Annette L Shafer; John H Weathersby

2012-09-01

The National Nuclear Security Administration (NNSA) has a need to develop and field a low-cost option for the long-term storage of a variety of radiological material. The storage option’s primary requirement is to provide both environmental and physical protection of the materials. Design criteria for this effort require a low initial cost and minimum maintenance over a 50-year design life. In 1999, Argonne National Laboratory-West was tasked with developing a dry silo storage option for the BN-350 Spent Fuel in Aktau Kazakhstan. Argon’s design consisted of a carbon steel cylinder approximately 16 ft long, 18 in. outside diameter and 0.375 in. wall thickness. The carbon steel silo was protected from corrosion by a duplex coating system consisting of zinc and epoxy. Although the study indicated that the duplex coating design would provide a design life well in excess of the required 50 years, the review board was concerned because of the novelty of the design and the lack of historical use. In 2012, NNSA tasked Idaho National Laboratory (INL) with reinvestigating the silo storage concept and development of alternative corrosion protection strategies. The 2012 study, “Silo Storage Concepts, Cathodic Protection Options Study” (INL/EST-12-26627), concludes that the option which best fits the design criterion is a passive cathotic protection scheme, consisting of a carbon steel tube coated with zinc or a zinc-aluminum alloy encapsulated in either concrete or a cement grout. The hot dipped zinc coating option was considered most efficient, but the flame-sprayed option could be used if a thicker zinc coating was determined to be necessary.

Effects of fire exposure on integrity of UF6 shipping cylinders

International Nuclear Information System (INIS)

Barlow, C.R.; Ziehlke, K.T.; Pryor, W.A.

1985-01-01

Two 2-1/2-ton steel cylinders for the transport of uranium hexafluoride within the United States nuclear fuel enrichment cycle were involved in a warehouse fire where portions of the cylinders were estimated to have reached a temperature of 1600 0 F (870 0 C). The cylinders were empty at the time of the fire and therefore were not in protective overpacks in which full product cylinders are handled while in transit. Hydrostatic tests to failure showed that the integrity of the cylinders was not degraded by exposure to the temperatures generated by the fire. They withstood test pressures in excess of 10 times the design pressure, and showed a volume expansion of 30% above the original capacity before rupture in a completely ductile fashion. Reference CAPE-323. 9 figs

Four-Cylinder Stirling-Engine Computer Program

Science.gov (United States)

Daniele, C. J.; Lorenzo, C. F.

1986-01-01

Computer program developed for simulating steady-state and transient performance of four-cylinder Stirling engine. In model, four cylinders interconnected by four working spaces. Each working space contains seven volumes: one for expansion space, heater, cooler, and compression space and three for regenerator. Thermal time constant for regenerator mass associated with each regenator gas volume. Former code generates results very quickly, since it has only 14 state variables with no energy equation. Current code then used to study various aspects of Stirling engine in much more detail. Program written in FORTRAN IV for use on IBM 370 computer.

Lattice Boltzmann simulation of viscoelastic flow past a confined free rotating cylinder

Science.gov (United States)

Xia, Yi; Zhang, Peijie; Lin, Jianzhong; Ku, Xiaoke; Nie, Deming

2018-05-01

To study the dynamics of rigid body immersed in viscoelastic fluid, an Oldroyd-B fluid flow past an eccentrically situated, free rotating cylinder in a two-dimensional (2D) channel is simulated by a novel lattice Boltzmann method. Two distribution functions are employed, one of which is aimed to solve Navier-Stokes equation and the other to the constitutive equation, respectively. The unified interpolation bounce-back scheme is adopted to treat the moving curved boundary of cylinder, and the novel Galilean invariant momentum exchange method is utilized to obtain the hydrodynamic force and torque exerted on the cylinder. Results show that the center-fixed cylinder rotates inversely in the direction where a cylinder immersed in Newtonian fluid do, which generates a centerline-oriented lift force according to Magnus effect. The cylinder’s eccentricity, flow inertia, fluid elasticity and viscosity would affect the rotation of cylinder in different ways. The cylinder rotates more rapidly when located farther away from the centerline, and slows down when it is too close to the wall. The rotation frequency decreases with increasing Reynolds number, and larger rotation frequency responds to larger Weissenberg number and smaller viscosity ratio, indicating that the fluid elasticity and low solvent viscosity accelerates the flow-induced rotation of cylinder.

Flow and flow-induced vibration of a square array of cylinders in steady currents

Energy Technology Data Exchange (ETDEWEB)

Zhao, Ming [School of Computing, Engineering and Mathematics, University of Western Sydney, Locked Bag 1797, Penrith, NSW 2751 (Australia); Cheng, Liang; An, Hongwei; Tong, Feifei, E-mail: m.zhao@uws.edu.au [School of Civil, Environmental and Mining Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 (Australia)

2015-08-15

Flow and flow-induced vibration of a square array of cylinders are investigated by two-dimensional numerical simulations. Flow past 36 cylinders in an inline arranged square array and 33 cylinders in a staggered arranged square array is firstly simulated, for Re = 100 and the spacing ratios of L/D = 1.5, 2, 3, 4, 5. Only one vortex street is observed in the wake of the cylinder array when the spacing ratio is 1.5 in the inline arrangement and 1.5 and 2 in the staggered arrangement, indicating that the critical spacing ratio for the single-vortex street mode in the staggered arrangement is higher than that in the inline arrangement. The vortex shedding from the cylinders is suppressed at L/D = 3 for both inline and staggered arrangements. Vortex shedding from each individual cylinder is observed when L/D = 4. Flow-induced vibration of 36 cylinders in an inline square arrangement is studied for a constant Reynolds number of 100, two spacing ratios of 2 and 5, a constant mass ratio of 2.5 and a wide range of reduced velocities. It is found that for a spacing ratio of 2, the vibration of the cylinders in the four downstream columns does not start until the reduced velocity exceeds 4.5. The vibration of the cylinders progresses downstream with increasing reduced velocity. For a spacing ratio of 5, the vibrations of the cylinders in the most upstream column are similar to that of a single cylinder. The vibration amplitudes of the downstream cylinders peak at higher reduced velocities than that of a single cylinder. The maximum possible response amplitudes occur at the most downstream cylinders. (paper)

Dynamic Fracture Simulations of Explosively Loaded Cylinders

Energy Technology Data Exchange (ETDEWEB)

Arthur, Carly W. [Univ. of California, Davis, CA (United States). Dept. of Civil and Environmental Engineering; Goto, D. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2015-11-30

This report documents the modeling results of high explosive experiments investigating dynamic fracture of steel (AerMet® 100 alloy) cylinders. The experiments were conducted at Lawrence Livermore National Laboratory (LLNL) during 2007 to 2008 [10]. A principal objective of this study was to gain an understanding of dynamic material failure through the analysis of hydrodynamic computer code simulations. Two-dimensional and three-dimensional computational cylinder models were analyzed using the ALE3D multi-physics computer code.

Relaxation of Thick-Walled Cylinders and Spheres

DEFF Research Database (Denmark)

Saabye Ottosen, N.

1982-01-01

Using the nonlinear creep law proposed by Soderberg, (1936) closed-form solutions are derived for the relaxation of incompressible thick-walled spheres and cylinders in plane strain. These solutions involve series expressions which, however, converge very quickly. By simply ignoring these series...... expressions, extremely simple approximate solutions are obtained. Despite their simplicity these approximations possess an accuracy that is superior to approximations currently in use. Finally, several physical aspects related to the relaxation of cylinders and spheres are discussed...

Bristol cylinder. Vol. 3A - technical appraisal

Energy Technology Data Exchange (ETDEWEB)

1983-06-01

A consultants' report is presented on a UK funded wave energy device known as the Bristol Cylinder. A detailed engineering appraisal is given for each component and aspects of the device including installation, power generation and maintenance. Finally the discounted cost of energy from the device is assessed. For all topics the views of the consultants are compared with those of the team developing the Bristol Cylinder and where discrepancies occur, these are explained and discussed.

Flow Features of Three Side-by-side Circular Cylinders at Low Reynolds Number

Directory of Open Access Journals (Sweden)

Liu Junkao

2016-01-01

Full Text Available In order to study the fluctuation of kinetic parameter of cylinder matrix in incompressible stationary flow, the flow fluid around three side-by-side circular cylinders are simulated using Immersed Boundary–Lattice Boltzmann method (IB-LBM. Drag and lift force of the three cylinders are investigated as the interval between each cylinder varied from zero to five times of the cylinder diameter. Five flow patterns are defined according to the vortices structure in the downstream of the cylinders. Power spectrum analysis of lift force is developed to explain the vortex patterns. Through the research, we find the strength and phase of the gap flow play an important role in the vortex formatting process. The vortices shedding from different cylinders neutralize and combine in the near wake, contributing a lot to the variation of forces.

Extended Analytic Linear Model of Hydraulic Cylinder With Respect Different Piston Areas and Volumes

Directory of Open Access Journals (Sweden)

Petr KOŇAŘÍK

2009-06-01

Full Text Available Standard analytic linear model of hydraulic cylinder usually comes from assumptions of identical action piston areas on both sides of hydraulic cylinder (double piston rod and suitable operation point, which is usually chosen in the middle of piston. By reason of that volumes inside of cylinder are than same. Moreover for control of that arrangement of hydraulic cylinder, usually controlled by 4/3 servovalve, the same mount of flows comes in and comes out to each of chambers of hydraulic cylinder. Presented paper deal with development of extended form of analytic linear model of single piston rod hydraulic cylinder which respects different action piston areas and volumes inside of chambers of hydraulic cylinder and also two different input flows of hydraulic cylinder. In extended model are also considered possibilities of different dead volumes in hoses and intake parts of hydraulic cylinder. Dead volume has impact on damping of hydraulic cylinder. Because the system of hydraulic cylinder is generally presented as a integrative system with inertia of second order: eq , we can than obtain time constants and damping of hydraulic cylinder for each of analytic form model. The model has arisen for needs of model fractionation on two parts. Part of behaviour of chamber A and part of behaviour of chamber B of cylinder. It was created for the reason of analysis and synthesis of control parameters of regulation circuit of multivalve control concept of hydraulic drive with separately controlled chamber A and B which could be then used for.

Optimization of In-Cylinder Pressure Filter for Engine Research

Science.gov (United States)

2017-06-01

ARL-TR-8034 ● JUN 2017 US Army Research Laboratory Optimization of In-Cylinder Pressure Filter for Engine Research by Kenneth...Laboratory Optimization of In-Cylinder Pressure Filter for Engine Research by Kenneth S Kim, Michael T Szedlmayer, Kurt M Kruger, and Chol-Bum M...

In-depth Study on Cylinder Wake Controlled by Lorentz Force

International Nuclear Information System (INIS)

Zhang Hui; Fan Bao-Chun; Chen Zhi-Hua

2011-01-01

The underlying mechanisms of the electromagnetic control of cylinder wake are investigated and discussed. The effects of Lorentz force are found to be composed of two parts, one is its direct action on the cylinder (the wall Lorentz force) and the other is applied to the fluid (called the field Lorentz force) near the cylinder surface. Our results show that the wall Lorentz force can generate thrust and reduce the drag; the field Lorentz force increases the drag. However, the cylinder drag is dominated by the wall Lorentz force. In addition, the field Lorentz force above the upper surface decreases the lift, while the upper wall Lorentz force increases it. The total lift is dominated by the upper wall Lorentz force. (fundamental areas of phenomenology(including applications))

Method and apparatus for filling cryogenic liquid cylinders

International Nuclear Information System (INIS)

Remes, S.

1984-01-01

A method and apparatus are disclosed for filling a portable cryogenic liquid cylinder from a large stand tank. The invention employs a regulator valve to perform an automatic throttling function whereby the pressure in the liquid cylinder is maintained at a value slightly lower than the upstream pressure in the stand tank. This significantly reduces filling losses due to flashing

System and method of cylinder deactivation for optimal engine torque-speed map operation

Science.gov (United States)

Sujan, Vivek A; Frazier, Timothy R; Follen, Kenneth; Moon, Suk-Min

2014-11-11

This disclosure provides a system and method for determining cylinder deactivation in a vehicle engine to optimize fuel consumption while providing the desired or demanded power. In one aspect, data indicative of terrain variation is utilized in determining a vehicle target operating state. An optimal active cylinder distribution and corresponding fueling is determined from a recommendation from a supervisory agent monitoring the operating state of the vehicle of a subset of the total number of cylinders, and a determination as to which number of cylinders provides the optimal fuel consumption. Once the optimal cylinder number is determined, a transmission gear shift recommendation is provided in view of the determined active cylinder distribution and target operating state.

Developing business opportunities for hydrogen storage

International Nuclear Information System (INIS)

Thompson, R.

2001-01-01

A quick review of the history of Dynetek Industries Limited was provided. During the period 1991-1995, it began research and development efforts in the field of advanced lightweight fuel storage systems and the DyneCell R Fuel Storage Systems was introduced on the market. In 1997, it began supplying Ballard Power Systems with hydrogen fuel tanks. Trading on the Toronto Stock Exchange started in September 2000, and in 2001 Dynetek incorporated a 100 per cent European subsidiary, Dynetek Europe GmbH. The advantages of the product are numerous: lightest cylinder on the market with a metallic liner, highest storage capacity of all lightweight designs, non-permeable, one piece, seamless aluminium liner, and true fast-fill capabilities to name but a few. Dynetek's vision of market development was introduced. It involves a California demonstration project for the period 2001-2003 which should lead to transit vehicles in 2005-2008. Fleet vehicles are expected to follow suit during the same period, and the consumer market should be ripe in 2010-2015. Some of the challenges facing the industry were discussed and Dynetek's role in meeting them was examined. figs

Vortex shedding from tandem cylinders

Science.gov (United States)

Alam, Md. Mahbub; Elhimer, Mehdi; Wang, Longjun; Jacono, David Lo; Wong, C. W.

2018-03-01

An experimental investigation is conducted on the flow around tandem cylinders for ranges of diameter ratio d/ D = 0.25-1.0, spacing ratio L/ d = 5.5-20, and Reynolds number Re = 0.8 × 104-2.42 × 104, where d and D are the diameters of the upstream and downstream cylinders, respectively, L is the distance from the upstream cylinder center to the forward stagnation point of the downstream one. The focus is given on examining the effects of d/ D, L/ d and Re on Strouhal number St, flow structures and fluid forces measured using hotwire, particle image velocimetry (PIV) and load cell measurement techniques, respectively. Changes in d/ D and L/ d in the ranges examined lead to five flow regimes, namely lock-in, intermittent lock-in, no lock-in, subharmonic lock-in and shear-layer reattachment regimes. Time-mean drag coefficient ( C D) and fluctuating drag and lift coefficients ({C^'D} and {C^'L}) are more sensitive to L/ d than d/ D. The scenario is opposite for St where d/ D is more prominent than L/ d to change the St. The detailed facet of the dependence on d/ D and L/ d of C D, {C^'D}, {C^'L} and St is discussed based on shear-layer velocity, approaching velocity, vortex formation length, and wake width.

MINE WASTE TECHNOLOGY PROGRAM; PHOSPHATE STABILIZATION OF HEAVY METALS CONTAMINATED MINE WASTE YARD SOILS, JOPLIN, MISSOURI NPL SITE

Science.gov (United States)

This document summarizes the results of Mine Waste Technology Project 22-Phosphate Stabilization of Heavy Metals-Contaminated Mine Waste Yard Soils. Mining, milling, and smelting of ores near Joplin, Missouri, have resulted in heavy metal contamination of the area. The Joplin s...

Faraday effect in hollow quantum cylinder of finite thickness

International Nuclear Information System (INIS)

Ismailov, T.G.; Jabrailova, G.G.

2009-01-01

The interband Faraday rotation in hollow quantum cylinder of finite thickness is theoretically investigated. Faraday rotation in the dependence on incident light energy for different values of cylinder thickness. It is seen that the resonance peaks appear on Faraday rotation curve. The roles of selection are obtained

Infinitely long cylinder in a sinusoidal field (Problem 2)

International Nuclear Information System (INIS)

Ida, N.

1986-01-01

The results presented here were obtained with a 2-D (and axisymmetric) eddy current program called EDDYNDT. The program uses the magnetic vector potential formulation and was specifically designed for the calculation of coil impedances in NDT applications. For normal applications, flux densities, forces, eddy current densities and stored and dissipated energies are not calculated. The program required minor modifications to calculated these quantities form the magnetic vector potential. In its present form, program EDDYNDT cannot handle flux normal boundary conditions. To avoid this, half the cylinder was modeled as opposed to the quarter cylinder in the mesh recommended in the problem outline. This increased the number of elements and nodes but did not change their density or location. Both a solution without the cylinder and a solution with the cylinder are presented. The fields presented are calculated at the center of each element. For this reason, the values presented are interpolated between neighboring elements. This creates a problem, particularly at discontinuities where the errors are largest

Rolling Cylinder Phase 1

DEFF Research Database (Denmark)

Margheritini, Lucia; Taraborrelli, Valeria Taraborrelli

Margheritini and Valeria Taraborrelli(valeria.taraborrelli@hotmail.it) with a total of 3 day visit from the developers. Laboratory tests in irregular waves will be performed by Lucia Margheritini. The report is aimed at the first stage testing of the Rolling Cylinder wave energy device. This phase includes...

Electrostatics of spherical metallic particles in cylinder electrostatic separators/sizers

International Nuclear Information System (INIS)

Lu Hongzhou; Li Jia; Guo Jie; Xu Zhenming

2006-01-01

This paper presents a theoretical analysis of the dynamics of spherical metallic particles in electrostatic separators/sizers (ESSs). A computational algorithm is employed to depict the cylinder-type electrode arrangements applied in some electrostatic processes generating non-uniform electric fields. The ESS consists of a pair of conducting cylinders. The upper cylinder is energized by HVdc, while the lower one is grounded and mounted horizontally on a revolvable axis. The aim of this paper is to present a new electrode configuration and demonstrate the usefulness of numerical techniques for the evaluation of the particle's motion. A computer program was employed for analysing the behavior of spherical particles in a two-dimensional electrode arrangement that models the actual electric field configuration of cylinder-type electrostatic separators/sizers. The analysis is needed for the development of any new application of this cylinder-type electrode arrangement as an electrostatic separation method. The results reveal that the particle's motion depends on its radius and density and amplitude of the applied voltage. The actual granular mixtures with different specific mass and radius could be separated applying this cylinder-type electrostatic separation method; the lift voltage is an important parameter for separation. With a program for two-dimensional analysis of the electric field, the computational procedure presented in this paper could be employed for any particle shapes

Bubbly flows around a two-dimensional circular cylinder

Science.gov (United States)

Lee, Jubeom; Park, Hyungmin

2016-11-01

Two-phase cross flows around a bluff body occur in many thermal-fluid systems like steam generators, heat exchangers and nuclear reactors. However, our current knowledge on the interactions among bubbles, bubble-induced flows and the bluff body are limited. In the present study, the gas-liquid bubbly flows around a solid circular cylinder are experimentally investigated while varying the mean void fraction from 5 to 27%. The surrounding liquid (water) is initially static and the liquid flow is only induced by the air bubbles. For the measurements, we use the high-speed two-phase particle image velocimetry techniques. First, depending on the mean void fraction, two regimes are classified with different preferential concentration of bubbles in the cylinder wake, which are explained in terms of hydrodynamic force balances acting on rising bubbles. Second, the differences between the two-phase and single-phase flows (while matching their Reynolds numbers) around a circular cylinder will be discussed in relation to effects of bubble dynamics and the bubble-induced turbulence on the cylinder wake. Supported by a Grant (MPSS-CG-2016-02) through the Disaster and Safety Management Institute funded by Ministry of Public Safety and Security of Korean government.

Case Report: Facial and eye injury following a fridge cylinder gas explosion

Directory of Open Access Journals (Sweden)

Monsudi Kehinde Fasasi

2017-11-01

Full Text Available Fridge cylinders contain liquefied petroleum gas (LPG, an inflammable gas of mixture of propane and butane [1]. It’s colourless but odourised to give warning during leakage. Injury from accidental fridge cylinder explosion is similar to any other blast injuries in terms of the release of hot gases, blast wave and metal fragments resulting in extensive skin burns, abrasions, penetrating injury and tissue loss [2-4]. Ocular trauma following gas cylinder explosion is rare however, Babar et al reported 20% of ocular trauma to be secondary to gas cylinder and battery explosion [2]. To our knowledge, this is the first case of facial and eye injury following a fridge cylinder gas explosion reported in the literature.

Adsorptive storage of natural gas

International Nuclear Information System (INIS)

Yan, Song; Lang, Liu; Licheng, Ling

2001-01-01

The Adsorbed Natural Gas (ANG) storage technology is reviewed. The present status, theoretical limits and operational problems are discussed. Natural gas (NG) has a considerable advantage over conventional fuels both from an environmental point of view and for its natural abundance. However, as well known, it has a two fold disadvantage compared with liquid fuels: it is relatively expensive to transport from the remote areas, and its energy density (heat of combustion/volume) is low. All these will restrict its use. Compressed natural gas (CNG) may be a solution, but high pressures are needed (up to 25 MPa) for use in natural-gas fueled vehicles, and the large cost of the cylinders for storage and the high-pressure facilities necessary limit the practical use of CNG. Alternatively, adsorbed natural gas (ANG) at 3 - 4 MPa offers a very high potential for exploitation in both transport and large-scale applications. At present, research about this technology mainly focuses on: to make adsorbents with high methane adsorption capacity; to make clear the effects of heat of adsorption and the effect of impurities in natural gas on adsorption and desorption capacity. This paper provides an overview of current technology and examines the relations between fundamentals of adsorption and ANG storage. (authors)

Performance of A Horizontal Cylinder Type Rotary Dryer for Drying Process ofOrganic Compost from Solid Waste Cocoa Pod

Directory of Open Access Journals (Sweden)

Sukrisno Widyotomo

2008-07-01

Full Text Available Cocoa pod husk is the bigest component of cocoa pod, about 70% of total ht of mature pod, and to potentially used as organic compost source. Poten tial solid waste of cocoa pod husk from a cocoa processing centre is about 15— 22 m3/ha/year. A cocoa plantation needs about 20—30 ton/ha/year of organic matters. One of important steps in compos processing technology of cocoa pod solid waste is drying process. Organic compost with 20% moisture content is more easy in handling, application, storage and distribution. Indonesian Coffee and Cocoa Research Institute has designed and tested a horizontal cylinder type rotary dryer for drying process of organic compos from solid waste cocoa pod with kerosene burner as energy sources. The objective of this research is to study performance of a horizontal cylinder type rotary dryer using kerosene burner as energy source for drying process of organic compost from solid waste cocoa pod. The material used was solid waste cocoa pod with 70—75% moisture content (wet basis, 70% size particle larger than 4.76 mm, and 30% size particle less than 4.76 mm, 690—695 kg/m3 bulk density. Drying process temperatures treatment were 60OC, 80OC, and 100OC, and cylinder rotary speed treatments were 7 rpm, 10 rpm, dan 16 rpm. The results showed that dryer had capacity about 102—150 kg/h depend on drying temperature and cylinder rotary speed. Optimum operation condition at 100OC drying temperature, and 10 rpm cylinder rotary speed with drying time to reach final moisture content of 20% was 1,6 h, capacity 136,14 kg/ h, bulk density 410 kg/m3, porocity 45,15%, kerosene consumption as energy source was 2,57 l/h, and drying efficiency 68,34%. Key words : cocoa, drying, rotary dryer, compost, waste

Large eight.cylinder Stirling engine for biofuels

DEFF Research Database (Denmark)

Carlsen, Henrik; Biedermann, F.; Bovin, Jonas Kabell

2003-01-01

A large Stirling engine with an electric power output of 70 kW has been developed for small-scale CHP using wood chips and other sorts of biomass as fuel. The development of the engine is based on the results from the development of a four-cylinder Stirling engine with a power output of 35 k...... in the hot end connecting the expansion space with the hot end of the regenerator through the heater panel. However, this has resulted in comparably large dead volumes and flow losses in the connections between the heater and the regenerator/expansion volume. For the new eight-cylinder engine the design...... of the connections between the heater and the regenerator/expansion volume have been improved considerably, reducing the flow losses and internal dead volume. Results from simulations indicate an improvement of power output and efficiency of about 10%. A four cylinder double acting Stirling engine is basically...

77 FR 37712 - High Pressure Steel Cylinders From China

Science.gov (United States)

2012-06-22

...), that an industry in the United States is materially injured by reason of imports of high pressure steel... preliminary determinations by Commerce that imports of high pressure steel cylinders from China were... Publication 4328 (June 2012), entitled High Pressure Steel Cylinders from China: Investigation Nos. 701-TA-480...

Vortex-induced vibrations of a square cylinder under linear shear flow

Energy Technology Data Exchange (ETDEWEB)

Sun, Wenjuan; Zhou, Dai; Han, Zhaolong [School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Tu, Jiahuang, E-mail: tujiahuang1982@163.com, E-mail: han.arkey@gmail.com [College of Civil Engineering and Mechanics, Xiangtan University, Xiangtan, Hunan 411105 (China)

2017-04-15

This paper investigates the numerical vortex-induced vibration (VIV) of a square cylinder which is connected to a 2-DOF mass-spring system and is immersed in the planar shear flow by employing a characteristic-based split (CBS) finite element method (FEM). The reduced mass of the square cylinder is M {sub r} = 2, while the reduced velocity, U {sub r}, is changed from 3 to 12 with an increment of Δ U {sub r} = 1. The effects of some key parameters on the cylinder dynamic responses, vibrating frequencies, the flow patterns as well as the energy transferred between the fluid and cylinder are revealed. In this study, the key parameters are selected as follows: shear ratio ( k  = 0, 0.05 and 0.1) and Reynolds numbers ( Re  = 80 and 160). Numerical results demonstrate that the X – Y trajectories of the cylinder mainly appear as a symmetrical figure ‘8’ in uniform flow ( k  = 0) and an unsymmetrical figure ‘8’ and ‘O’ in shear flows ( k  = 0.05 and 0.1). The maximum oscillation amplitudes of the square cylinder in both the inline and transverse directions have distinct characteristics compared to that of a circular cylinder. Two kinds of flow patterns, ‘2S’ and ‘P + S’, are mainly observed under the shear flow. Also, the mean values of the energy of the cylinder system increase with the reduced velocity, while the root mean square (rms) of the energy reaches its peak value at reduced velocity U {sub r} = 5. (paper)

Rotation of an immersed cylinder sliding near a thin elastic coating

Science.gov (United States)

Rallabandi, Bhargav; Saintyves, Baudouin; Jules, Theo; Salez, Thomas; Schönecker, Clarissa; Mahadevan, L.; Stone, Howard A.

2017-07-01

It is known that an object translating parallel to a soft wall in a viscous fluid produces hydrodynamic stresses that deform the wall, which in turn results in a lift force on the object. Recent experiments with cylinders sliding under gravity near a soft incline, which confirmed theoretical arguments for the lift force, also reported an unexplained steady-state rotation of the cylinders [B. Saintyves et al., Proc. Natl. Acad. Sci. USA 113, 5847 (2016), 10.1073/pnas.1525462113]. Motivated by these observations, we show, in the lubrication limit, that an infinite cylinder that translates in a viscous fluid parallel to a soft wall at constant speed and separation distance must also rotate in order to remain free of torque. Using the Lorentz reciprocal theorem, we show analytically that for small deformations of the elastic layer, the angular velocity of the cylinder scales with the cube of the sliding speed. These predictions are confirmed numerically. We then apply the theory to the gravity-driven motion of a cylinder near a soft incline and find qualitative agreement with the experimental observations, namely, that a softer elastic layer results in a greater angular speed of the cylinder.

Buckling behaviour of imperfect ring-stiffened cone-cylinder intersections under internal pressure

International Nuclear Information System (INIS)

Zhao, Y.

2005-01-01

Cone-cylinder intersections are used commonly in pressure vessels and piping. In the case of a cone large end-to-cylinder intersection under internal pressure, the intersection is subject to a large circumferential compressive force. While both the cone and the cylinder may be locally thickened to strengthen the intersection, it is often desirable and convenient to provide an annular plate ring at the cone-to-cylinder joint to supplement local thickening or as an alternative strengthening measure, leading to a ring-stiffened cone-cylinder intersection. Only limited work has been carried out specifically on ring-stiffened cone-cylinder intersections under internal pressure. This paper presents the first experimental study on such intersections. In addition to the presentation of test results including geometric imperfections, failure behaviour and the determination of buckling mode and load based on displacement measurements, results from nonlinear bifurcation analysis using the perfect shape and nonlinear analysis using the measured imperfect shape are presented and compared with the experimental results

CYLINDER OF THE DISPOSABLE MASS EXCHANGE DEVICE FOR HEMOSORPTION

Directory of Open Access Journals (Sweden)

F. I. Kazakov

2015-01-01

Full Text Available BACKGROUND. Hemocarboperfusion, previously widely used in our country, can universally pass out of use due to the lack of industrial production of disposable mass exchange devices.MATERIAl AND METHODS. Physicochemical properties of materials and design features of the body samples elements of various sizes have been studied.RESULTS. The elements and materials properties of the hemosorption mass exchanger cylinder have been studied. Hydrodynamic parameters of manipulation using the developed cylinders at different perfusion rates have been studied in bench experiments.CONCLUSION. The original cylinder of the disposable mass exchange device for hemosorption, which meets the current clinical needs, has been developed. 

Finite-size resonance dielectric cylinder in a rectangular waveguide

International Nuclear Information System (INIS)

Chuprina, V.N.; Khizhnyak, N.A.

1988-01-01

The problem on resonance spread of an electromagnetic wave by a dielectric circular cylinder of finite size in a rectangular waveguide is solved by a numerical-analytical method. The cylinder axes are parallel. The cylinder can be used as a resonance tuning element in accelerating SHF-sections. Problems on cutting off linear algebraic equation systems, to which relations of macroscopic electrodynamics in the integral differential form written for the concrete problem considered here are reduced by analytical transformations, are investigated in the stage of numerical analysis. Theoretical dependences of the insertion of the voltage standing wave coefficient on the generator wave length calculated for different values of problem parameters are constracted

Summary of the engineering analysis report for the long-term management of depleted uranium hexafluoride

International Nuclear Information System (INIS)

Dubrin, J.W.; Rahm-Crites, L.

1997-09-01

The Department of Energy (DOE) is reviewing ideas for the long-term management and use of its depleted uranium hexafluoride. DOE owns about 560,000 metric tons (over a billion pounds) of depleted uranium hexafluoride. This material is contained in steel cylinders located in storage yards near Paducah, Kentucky; Portsmouth, Ohio; and at the East Tennessee Technology Park (formerly the K-25 Site) in Oak Ridge, Tennessee. On November 10, 1994, DOE announced its new Depleted Uranium Hexafluoride Management Program by issuing a Request for Recommendations and an Advance Notice of Intent in the Federal Register (59 FR 56324 and 56325). The first part of this program consists of engineering, costs and environmental impact studies. Part one will conclude with the selection of a long-term management plan or strategy. Part two will carry out the selected strategy

Summary of the engineering analysis report for the long-term management of depleted uranium hexafluoride

Energy Technology Data Exchange (ETDEWEB)

Dubrin, J.W., Rahm-Crites, L.

1997-09-01

The Department of Energy (DOE) is reviewing ideas for the long-term management and use of its depleted uranium hexafluoride. DOE owns about 560,000 metric tons (over a billion pounds) of depleted uranium hexafluoride. This material is contained in steel cylinders located in storage yards near Paducah, Kentucky; Portsmouth, Ohio; and at the East Tennessee Technology Park (formerly the K-25 Site) in Oak Ridge, Tennessee. On November 10, 1994, DOE announced its new Depleted Uranium Hexafluoride Management Program by issuing a Request for Recommendations and an Advance Notice of Intent in the Federal Register (59 FR 56324 and 56325). The first part of this program consists of engineering, costs and environmental impact studies. Part one will conclude with the selection of a long-term management plan or strategy. Part two will carry out the selected strategy.

Speed-variable Switched Differential Pump System for Direct Operation of Hydraulic Cylinders

DEFF Research Database (Denmark)

Schmidt, Lasse; Roemer, Daniel Beck; Pedersen, Henrik Clemmensen

2015-01-01

differential cylinders. The main idea was here to utilize an electric rotary drive, with the shaft interconnected to two antiparallel fixed displacement gear pumps, to actuate a differential cylinder. With the design carried out such that the area ratio of the cylinder matches the displacement ratio of the two...

Chlorine leak on Mumbai Port Trust's Sewri yard: A case study

Science.gov (United States)

Sharma, Rakesh Kumar; Chawla, Raman; Kumar, Surendra

2010-01-01

Chemical emergencies involving hazardous chemicals are not uncommon in India. More than 25 incidents have been identified in National Disaster Management Guidelines – Chemical (Industrial) Disaster Management, released in May 2007. In a recent occurrence on the morning of 14 July 2010, nearly at 3:00 a.m., chlorine leak was reported from a gas cylinder referred as turner, weighing about 650 kg, corroding with time at the Haji Bunder hazardous cargo warehouse in Mumbai Port Trust, Sewri, affecting over 120 people in the neighborhood, including students, laborers, port workers and fire fighters, of whom 70 were reported critical. It has been observed to be a blatant case of ignorance and negligence as well as contraventions to the safety and environmental safeguard requirements under existing statues as well as non-maintenance of failsafe conditions at the site requisite for chlorine storage. The analysis revealed significant gaps in the availability of neutralization mechanism and the chlorine stored in open increased the possibility of formation of ingress mixture due to busting of chlorine filled tankers. The Government of India has institutionalized emergency preparedness framework at national, state and district level as envisaged in Disaster Management Act, 2005, to prepare the nation to mitigate such incidences, if all the preventive safety provisions fail. Ministry of Environment and Forests (MoEF) is preparing National Action Plan-Chemical (Industrial) Disaster Management based on National Guidelines to implement all the mechanisms of capacity development across the country. PMID:21829311

Induced-charge electroosmosis around conducting and Janus cylinder in microchip

Directory of Open Access Journals (Sweden)

Zhang Kai

2012-01-01

Full Text Available The induced-charge elecetroosmosis around conducting/Janus cylinder with arbitrary Debye thickness is studied numerically, when an direct current weak electric filed is suddenly applied in a confined microchannel. It’s found that there are four large circulations around the conducting cylinder, and the total flux in the microchannel is zero; there are two smaller circulations around the Janus cylinder, and they are compressed to wall. A bulk flux, which has a parabolic relation with the applied electric field, is also predicted.

Performance of a Horizontal Triple Cylinder Type Pulping Machine

Directory of Open Access Journals (Sweden)

Sukrisno Widyotomo

2011-05-01

Full Text Available Pulping is one important step in wet coffee processing method. Pulping process usually uses a machine which constructed by wood or metal materials. A horizontal single cylinder type of fresh coffee cherries pulping machine is the most popular machine in coffee processing. One of the weaknesses of a horizontal single cylinder type of fresh coffee cherries pulping machine is higher in broken beans. Broken bean is one of mayor aspects in defect system that contribute to low quality. Indonesian Coffee and Cocoa Research Institute has designed and tested a horizontal double cylinder type of fresh coffee cherries pulping machine which resulted in 12.6—21.4% of broken beans. To reduce percentage of broken beans, Indonesian Coffee and Cocoa Research Institute has developed and tested a horizontal triple cylinder type of fresh coffee cherries pulping machine. Material tested was fresh mature Robusta coffee cherries, 60—65% (wet basis moisture content; has classified on 3 levels i.e. unsorted, small and medium, and clean from metal and foreign materials. The result showed that the machine produced 6,340 kg/h in optimal capacity for operational conditions, 1400 rpm rotor rotation speed for unsorted coffee cherries with composition 55.5% whole parchment coffee, 3.66% broken beans, and 1% beans in wet skin.Key words : coffee, pulp, pulper, cylinder, quality.

Sound insulation of composite cylindrical shells: a comparison between a laminated and a sandwich cylinder

OpenAIRE

Yuan, Chongxin; Roozen, Bert; Bergsma, Otto; Beukers, Adriaan

2012-01-01

The fuselages of aircraft are modeled as a cylinder in this paper, and the sound insulations of a sandwich cylinder and a laminated cylinder are studied both experimentally and numerically. The cylinders are excited by an acoustic pressure and a mechanical force respectively. Results show that under acoustic excitation, the sandwich cylinder and the laminated one have a similar sound insulation below 3000 Hz, but the sandwich cylinder has a much larger sound insulation at higher frequencies. ...

Scattering cross-section of an inhomogeneous plasma cylinder

International Nuclear Information System (INIS)

Jiaming Shi; Lijian Qiu; Ling, Y.

1995-01-01

Scattering of em waves by the plasma cylinder is of significance in radar target detection, plasma diagnosis, etc. This paper discusses the general method to calculate the scattering cross-section of em waves from a plasma cylinder which is radially inhomogeneous and infinitely long. Numerical results are also provided for several plasma density profiles. The effect of the electron density distribution on the scattering cross-section is investigated

Force Control for a Pneumatic Cylinder Using Generalized Predictive Controller Approach

Directory of Open Access Journals (Sweden)

Ahmad ’Athif Mohd Faudzi

2014-01-01

Full Text Available Pneumatic cylinder is a well-known device because of its high power to weight ratio, easy use, and environmental safety. Pneumatic cylinder uses air as its power source and converts it to a possible movement such as linear and rotary movement. In order to control the pneumatic cylinder, controller algorithm is needed to control the on-off solenoid valve with encoder and pressure sensor as the feedback inputs. In this paper, generalized predictive controller (GPC is proposed as the control strategy for the pneumatic cylinder force control. To validate and compare the performance, proportional-integral (PI controller is also presented. Both controllers algorithms GPC and PI are developed using existing linear model of the cylinder from previous research. Results are presented in simulation and experimental approach using MATLAB-Simulink as the platform. The results show that the GPC is capable of fast response with low steady state error and percentage overshoot compared to PI.

Geophysical survey work plan for White Wing Scrap Yard (Waste Area Grouping 11) at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1994-02-01

The White Wing Scrap Yard, located on the U.S. Department of Energy's Oak Ridge Reservation, served as an aboveground storage and disposal area for contaminated debris and scrap from the Oak Ridge K-25 Site, the Oak Ridge Y-12 Plant, and the Oak Ridge National laboratory. The site is believed to have been active from the early 1950s until the mid-1960s. A variety of materials were disposed of at the site, including contaminated steel tanks and vehicles. As an interim corrective action, a surface debris removal effort was initiated in November 1993 to reduce the potential threat to human health and the environment from the radionuclide-contaminated debris. Following this removal effort, a geophysical survey will be conducted across the site to locate and determine the lateral extent of buried nonindigenous materials. This survey will provide the data necessary to prepare a map showing areas of conductivity and magnetic intensity that vary from measured background values. These anomalies represent potential buried materials and therefore can be targeted for further evaluation. This work plan outlines the activities necessary to conduct the geophysical survey

A branch-and-price algorithm to solve the integrated berth allocation and yard assignment problem in bulk ports

DEFF Research Database (Denmark)

Robenek, Tomáš; Umang, Nitish; Bierlaire, Michel

2014-01-01

In this research, two crucial optimization problems of berth allocation and yard assignment in the context of bulk ports are studied. We discuss how these problems are interrelated and can be combined and solved as a single large scale optimization problem. More importantly we highlight the diffe...

Re-examination of laminar flow over twin circular cylinders in tandem arrangement

Energy Technology Data Exchange (ETDEWEB)

Liu, Ming-Ming; Lu, Lin; Teng, Bin; Tang, Guo-Qiang [State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024 (China); Zhao, Ming [School of Computing, Engineering and Mathematics, University of Western Sydney, Penrith 2751 (Australia)

2014-04-01

Viscous fluid flow past two identical circular cylinders in a tandem arrangement is numerically investigated at a typical Reynolds number of 200. By considering a large span of spacing ratio (0.1 ⩽ G/D ⩽ 6.0) with a fine interval of 0.1 or less, the dependences on the spacing ratio of the drag force, lift force, lift fluctuation frequency, torque on the cylinder pair and phase difference between the lift fluctuations of the two cylinders are investigated in detail, where D is the diameter of the cylinder and G the surface-to-surface distance between the cylinders. The phase difference between the lift fluctuations of the two cylinders is addressed based on correlation analysis together with the phase diagram, which has received scarce attention before. The phase difference provides further understanding to the dependence of the wake evolutions behind the twin circular cylinders. The numerical investigations show that diverse regimes can be identified according to the dependence of the hydrodynamics on the spacing ratio. The hydrodynamic discontinuities at G/D = 0.9, which have previously been ignored, are reported in this work. The physical correlations between the hydrodynamic discontinuities and the wake patterns are presented. (paper)

Re-examination of laminar flow over twin circular cylinders in tandem arrangement

International Nuclear Information System (INIS)

Liu, Ming-Ming; Lu, Lin; Teng, Bin; Tang, Guo-Qiang; Zhao, Ming

2014-01-01

Viscous fluid flow past two identical circular cylinders in a tandem arrangement is numerically investigated at a typical Reynolds number of 200. By considering a large span of spacing ratio (0.1 ⩽ G/D ⩽ 6.0) with a fine interval of 0.1 or less, the dependences on the spacing ratio of the drag force, lift force, lift fluctuation frequency, torque on the cylinder pair and phase difference between the lift fluctuations of the two cylinders are investigated in detail, where D is the diameter of the cylinder and G the surface-to-surface distance between the cylinders. The phase difference between the lift fluctuations of the two cylinders is addressed based on correlation analysis together with the phase diagram, which has received scarce attention before. The phase difference provides further understanding to the dependence of the wake evolutions behind the twin circular cylinders. The numerical investigations show that diverse regimes can be identified according to the dependence of the hydrodynamics on the spacing ratio. The hydrodynamic discontinuities at G/D = 0.9, which have previously been ignored, are reported in this work. The physical correlations between the hydrodynamic discontinuities and the wake patterns are presented. (paper)

How many oxygen cylinders do you need to take on transport? A nomogram for cylinder size and duration.

Science.gov (United States)

Lutman, D; Petros, A J

2006-09-01

When undertaking patient retrieval, it is important to take adequate supplies of oxygen to ensure patient safety. Oxygen can be delivered via a flowmeter into a facemask or used to drive pneumatic ventilators. Given the lack of space in the back of an ambulance or helicopter, the numbers of cylinders that can be taken is limited, hence the number needed to complete the journey must be carefully calculated prior to embarking. We have produced nomograms to predict how many oxygen cylinders will be consumed during a given journey when using either a flowmeter or a commonly used transport ventilator.

Buckling Experiment on Anisotropic Long and Short Cylinders

Directory of Open Access Journals (Sweden)

Atsushi Takano

2016-07-01

Full Text Available A buckling experiment was performed on anisotropic, long and short cylinders with various radius-to-thickness ratios. The 13 cylinders had symmetric and anti-symmetric layups, were between 2 and 6 in terms of the length-to-radius ratio, between 154 and 647 in radius-to-thickness ratio, and made of two kinds of carbon fiber reinforced plastic (CFRP prepreg with high or low fiber modulus. The theoretical buckling loads for the cylinders were calculated from the previously published solution by using linear bifurcation theory considering layup anisotropy and transverse shear deformation and by using deep shell theory to account for the effect of length and compared with the test results. The theoretical buckling loads for the cylinders were calculated from the previously published solution by using linear bifurcation theory considering layup anisotropy and transverse shear deformation and by using deep shell theory to account for the effect of length. The knockdown factor, defined as the ratio of the experimental value to the theoretical value, was found to be between 0.451 and 0.877. The test results indicated that a large length-to-radius ratio reduces the knockdown factor, but the radius-to-thickness ratio and other factors do not affect it.

Wave propagation in coated cylinders with reference to fretting fatigue

Indian Academy of Sciences (India)

is to study stress wave propagation in cylinders with reference to high frequency fretting. ... The motivation for studying of fretting fatigue at higher frequency is to investigate the ... Hence focus in this work is given to thin rods and cylinders. The.

Flow past an axially aligned spinning cylinder: Experimental Study

Science.gov (United States)

Carlucci, Pasquale; Buckley, Liam; Mehmedagic, Igbal; Carlucci, Donald; Thangam, Siva

2017-11-01

Experimental investigation of flow past a spinning cylinder is presented in the context of its application and relevance to flow past projectiles. A subsonic wind tunnel is used to perform experiments on the flow past a spinning cylinder that is mounted on a forward sting and oriented such that its axis of rotation is aligned with the mean flow. The experiments cover a Reynolds number of range of up to 45000 and rotation numbers of up to 2 (based on cylinder diameter). Time-averaged mean flow and turbulence profiles in the wake flow are presented with and without spin along with comparison to published experimental data. Funded in part by the U. S. Army ARDEC, Picatinny Arsenal, NJ.

The Friction of Vehicle Brake Tandem Master Cylinder

International Nuclear Information System (INIS)

Kao, M J; Chang, H; Tsung, T T; Lin, H M

2006-01-01

The behaviour of an elastomeric seal for vehicle brake Tandem master cylinder is measured and analyzed in temperature and brake fluids changed. Working conditions are simulated for different piston rod velocity and cylinder supply pressure, in temperature rising, brakefluid boundary and Nanoaluminum oxide brakefluid oxide brakefluid lubrication. The result shows that Nanoaluminum oxide brakefluid with its ball shape can highly reduce friction coefficient to avoid seal excessive wear and reduce slick slip in brake applications

Radiation dose rates from UF{sub 6} cylinders

Energy Technology Data Exchange (ETDEWEB)

Friend, P.J. [Urenco, Capenhurst (United Kingdom)

1991-12-31

This paper describes the results of many studies, both theoretical and experimental, which have been carried out by Urenco over the last 15 years into radiation dose rates from uranium hexafluoride (UF{sub 6}) cylinders. The contents of the cylinder, its history, and the geometry all affect the radiation dose rate. These factors are all examined in detail. Actual and predicted dose rates are compared with levels permitted by IAEA transport regulations.

ORALLOY (93.2 235U) METAL CYLINDER WITH BERYLLIUM TOP REFLECTOR

International Nuclear Information System (INIS)

Bess, John D.; Montierth, Leland M.; Reed, Raymond L.; Mihalczo, John T.

2010-01-01

A variety of critical experiments were constructed of enriched uranium metal during the 1960s and 1970s at the Oak Ridge Critical Experiments Facility (ORCEF) in support of criticality safety operations at the Y-12 Plant. The purposes of these experiments included the evaluation of storage, casting, and handling limits for the Y-12 Plant and providing data for verification of calculation methods and cross-sections for nuclear criticality safety applications. These included solid cylinders of various diameters, annuli of various inner and outer diameters, two and three interacting cylinders of various diameters, and graphite and polyethylene reflected cylinders and annuli. Of the hundreds of delayed critical experiments, one experiment was comprised of a stack of approximately 7-inch-diameter metal discs. The bottom of the stack consisted of uranium with an approximate height of 4-1/8 inches. The top of the stack consisted of beryllium with an approximate height of 5-9/16 inches. This experiment was performed on August 20, 1963 by J. T. Mihalczo and R. G. Taylor (Ref. 1) with accompanying logbook. Both detailed and simplified model specifications are provided in this evaluation. This fast-spectra experiment was determined to represent an acceptable benchmark. The calculated eigenvalues for both the detailed and simple models are within approximately 0.5% of the benchmark values, but significantly greater than 3s from the benchmark value because the uncertainty in the benchmark is very small: ±0.0002 (1s). There is significant variability between results using different neutron cross section libraries, the greatest being a k eff of ∼0.65% . Unreflected and unmoderated experiments with the same highly enriched uranium metal parts were performed at the Oak Ridge Critical Experiments Facility in the 1960s and are evaluated in HEU MET FAST 051. Thin graphite reflected (2 inches or less) experiments also using the same highly enriched uranium metal parts are evaluated

Mobile Robot Localization by Remote Viewing of a Colored Cylinder

Science.gov (United States)

Volpe, R.; Litwin, T.; Matthies, L.

1995-01-01

A system was developed for the Mars Pathfinder rover in which the rover checks its position by viewing the angle back to a colored cylinder with different colors for different angles. The rover determines distance by the apparent size of the cylinder.

Cylinder head seal for piston engines especially internal combustion engines. Zylinderkopfdichtung fuer Hubkolbenmaschinen, insbesondere Brennkraftmaschinen

Energy Technology Data Exchange (ETDEWEB)

Kubis, H.; Winter, J.

1991-01-17

The invention concerns a cylinder head seal for reciprocating piston engines especially internal combustion engines and preferentially those with cylinder sleeves. With performances of internal combustion engines encreasing all the time it is becoming more and more difficult to seal the cylinder heat. The invention proposes a ring seal whose sides are plastically deformed when the cylinder headed screws are tightened. The inner deformations of the cylinder head resulting from the pressure forces inside the cylinder are compensated by means of elastic spring action of the combustion chamber sealing ring. The dimension of land, groove and sides are matched in such a way as to prevent any seal squeezing during plastification which would result in a deformation of the cylinder sleeve. The ring can therefore be set directly into the centering of the cylinder sleeve. Separate centering devices are not required.

Survey and analysis of selected jointly owned large-scale electric utility storage projects

Energy Technology Data Exchange (ETDEWEB)

1982-05-01

The objective of this study was to examine and document the issues surrounding the curtailment in commercialization of large-scale electric storage projects. It was sensed that if these issues could be uncovered, then efforts might be directed toward clearing away these barriers and allowing these technologies to penetrate the market to their maximum potential. Joint-ownership of these projects was seen as a possible solution to overcoming the major barriers, particularly economic barriers, of commercializaton. Therefore, discussions with partners involved in four pumped storage projects took place to identify the difficulties and advantages of joint-ownership agreements. The four plants surveyed included Yards Creek (Public Service Electric and Gas and Jersey Central Power and Light); Seneca (Pennsylvania Electric and Cleveland Electric Illuminating Company); Ludington (Consumers Power and Detroit Edison, and Bath County (Virginia Electric Power Company and Allegheny Power System, Inc.). Also investigated were several pumped storage projects which were never completed. These included Blue Ridge (American Electric Power); Cornwall (Consolidated Edison); Davis (Allegheny Power System, Inc.) and Kttatiny Mountain (General Public Utilities). Institutional, regulatory, technical, environmental, economic, and special issues at each project were investgated, and the conclusions relative to each issue are presented. The major barriers preventing the growth of energy storage are the high cost of these systems in times of extremely high cost of capital, diminishing load growth and regulatory influences which will not allow the building of large-scale storage systems due to environmental objections or other reasons. However, the future for energy storage looks viable despite difficult economic times for the utility industry. Joint-ownership can ease some of the economic hardships for utilites which demonstrate a need for energy storage.

Mechanical Integrity of Copper Canister Lid and Cylinder

International Nuclear Information System (INIS)

Karlsson, Marianne

2002-01-01

This report compiles finite element analyses performed to ensure the structural integrity of canisters used for storing of nuclear fuel waste of type BWR. The report comprises analyses performed on the canister lid and cylinder casing in order to determine static and long-term strength of the structure. The report analyses the mechanical response of the lid and flange of the copper canister when subjected to loads caused by pressure from swelling bentonite and from ground water at a depth of 500 meter. The loads acting on the canister are somewhat uncertain and the cases investigated in this report are possible cases. Load cases analysed are: Pressure 15 MPa uniformly distributed on lid and 5 MPa uniformly distributed on cylinder; Pressure 5 MPa uniformly distributed on lid and 15 MPa uniformly distributed on cylinder; Pressure 20 MPa uniformly distributed on lid and cylinder; Side pressures 10 MPa and 20 MPa uniformly distributed on part of the cylinder. Creep analyses are also performed in order to estimate the stresses that will arise when the canister is placed in the repository. The analyses in this report are recreated from the original analyses but the models differ in geometry. Also, there is no information in the original reports on material data, time-independent as well as creep data, and analysis procedure. The data used in the recreated analyses are based on information from References 2, 3, 6 and 7. The results presented in this report are based on the supplementary analyses. These results differ from the original results. Most likely this is due to differences in model geometry. The original results are appended to the report and are summarised for comparison with results from the supplementary analyses. Otherwise, these results are not further discussed. For all load cases, high tensile stresses are found in the lid fillet between the planar part and the flange. High tensile stresses are also found in the weld surface and on the outer side of the

Wave forces on cylinder submerged horizontally in shallow water

Energy Technology Data Exchange (ETDEWEB)

Mitani, H; Sasaki, K; Kobayashi, T; Nomura, N; Kawabe, H; Sugimoto, H

1976-12-01

To estimate the wave forces on offshore and/or coastal structures, the ideal method is undoubtedly to obtain the more accurate solution of hydrodynamic equations under suitable boundary conditions. However, in practice, it is difficult to introduce precise solutions under present technical levels because some important problems still remain. Among them is the unsteady boundary layers with separation around the objects. Consequently, every effort is being made in this field to approximate these conditions. Among these approximations, the Diffraction Wave Theory and the Morrison's Method are the most famous means in practice, although both still have some problems. Some problems with the traditional Finite Amplitude Wave Theories such as Stokes and Cnoidal Wave Theories are examined, and by applying additional computed results to the Morrison's formula, the estimated formula for wave forces on a cylinder submerged horizontally in shallow water is introduced. Subsequently, the applicability of the formula and also the specific characteristics of wave forces on a horizontally settled cylinder are investigated in detail, attaching first importance to the distinctions from the vertically settled cylinder, based on the comparison of computed results with experimental results. The experiments were carried out on two different diameters of cylinder, 70 mm and 140 mm, and bottom slopes of the experimental tanks, /sup 1///sub 100/ and /sup 1///sub 30/, under various conditions varying water depth, wave period, wave height and also setting position of cylinder.

Simulating thermal behavior of AECL's spent fuel dry storage system with CATHENA

International Nuclear Information System (INIS)

Sabourin, G.

1998-01-01

This paper documents the comparisons between CATHENA predictions and temperature measurements taken at the Gentilly-2 NPP spent fuel dry storage facility and in a mock--up of a storage basket placed inside a storage cylinder. It also presents CATHENA temperature predictions related to the storage of spent fuel in MACSTOR modules as planned for Ignalina NPP, Lithuania. CATHENA has been chosen because it can simulate many noncondensable gases including air and helium, and because of its great flexibility in the representation of the MACSTOR module geometry. The results of the simulations show good agreement with the experimental measurements. The two comparisons indicate that CATHENA can be used to simulate heat transfer from the fuel to the external air circuit of the spent fuel dry storage system. For the Ignalina MACSTOR module, containing RBMK fuel having higher heat release than typical CANDU fuel, CATHENA predicts that the maximum fuel temperature is expected to be around 240 deg C, giving an acceptable margin below the maximum allowed temperature of 300 deg C. In conclusion, this paper shows that the thermalhydraulic code CATHENA can accurately predict the thermal behavior AECL's air cooled spent fuel dry storage system. (author)

To mow or to mow less: Lawn mowing frequency affects bee abundance and diversity in suburban yards

Science.gov (United States)

Susannah B. Lerman; Alexandra R. Contosta; Joan Milam; Christofer Bang

2018-01-01

Green spaces embedded within the urban matrix, particularly residential yards, could mitigate negative aspects of urban development and provide pollinator habitat. Lawns represent a dominant green space, and their management consists of frequent mowing to inhibit the growth of ostensibly “weedy” species (e.g., dandelions and clover). Since widespread population...

Thermal convection of liquid sodium in inclined cylinders

Science.gov (United States)

Khalilov, Ruslan; Kolesnichenko, Ilya; Pavlinov, Alexander; Mamykin, Andrey; Shestakov, Alexander; Frick, Peter

2018-04-01

The effect of inclination on the low Prandtl number turbulent convection in a cylinder of unit aspect ratio was studied experimentally. The working fluid was sodium (Prandtl number Pr =0.0094 ), the measurements were performed for a fixed Rayleigh number Ra =(1.47 ±0.03 ) ×107 , and the inclination angle varied from β =0∘ (the Rayleigh-Bénard convection, the temperature gradient is vertical) up to β =90∘ (the applied temperature gradient is horizontal) with a step Δ β =10∘ . The effective axial heat flux characterized by the Nusselt number is minimal at β =0∘ and demonstrates a smooth growth with the increase of the cylinder inclination, reaching a maximum at angle β ≈70∘ and decreasing with a further increase of β . The maximal value of the normalized Nusselt number Nu (β )/Nu (0 ) was 1.21. In general, the dependence of Nu (β ) in a cylinder with unit aspect ratio is similar to what was observed in sodium convection in inclined long cylinders but is much weaker. The structure of the flow undergoes a significant transformation with inclination. Under moderate inclination (β ≲30∘ ), the fluctuations are strong and are provided by regular oscillations of large-scale circulation (LSC) and by turbulence. Under large inclination (β >60∘ ), the LSC is regular and the turbulence is weak, while in transient regimes (30∘border of transient and large inclinations. We find the first evidence of strong LSC fluctuations in low Prandtl number convective flow under moderate inclination. The rms azimuthal fluctuations of LSC, about 27∘ at β =0∘ , decrease almost linearly up to β =30∘ , where they are about 9∘. The angular fluctuations in the vicinity of the end faces are much stronger (about 37∘ at β =0∘ ) and weakly decrease up to β =20∘ . The strong anticorrelation of the fluctuations in two halves of the cylinder indicates the torsional character of LSC fluctuations. At β =30∘ , the intensity of the oscillations at the

Numerical simulation of VAWT on the effects of rotation cylinder

Science.gov (United States)

Xing, Shuda; Cao, Yang; Ren, Fuji

2017-06-01

Based on Finite Element Analysis Method, studying on Vertical Axis Wind Turbine (VAWT) which is added rotating cylinder in front of its air foils, especially focusing on the analysis of NACA6 series air foils about variation of lift to drag ratio. Choosing the most suitable blades with rotary cylinder added on leading edge. Analysis indicates that the front rotating cylinders on the VAWT is benefit to lift rise and drag fall. The most suitable air foil whose design lift coefficient is 0.8, the blades relative thickness is 20%, and the optimistic tip speed ratio is about 7.

A novel approach to estimating potential maximum heavy metal exposure to ship recycling yard workers in Alang, India

International Nuclear Information System (INIS)

Deshpande, Paritosh C.; Tilwankar, Atit K.; Asolekar, Shyam R.

2012-01-01

The 180 ship recycling yards located on Alang–Sosiya beach in the State of Gujarat on the west coast of India is the world's largest cluster engaged in dismantling. Yearly 350 ships have been dismantled (avg. 10,000 ton steel/ship) with the involvement of about 60,000 workers. Cutting and scrapping of plates or scraping of painted metal surfaces happens to be the commonly performed operation during ship breaking. The pollutants released from a typical plate-cutting operation can potentially either affect workers directly by contaminating the breathing zone (air pollution) or can potentially add pollution load into the intertidal zone and contaminate sediments when pollutants get emitted in the secondary working zone and gets subjected to tidal forces. There was a two-pronged purpose behind the mathematical modeling exercise performed in this study. First, to estimate the zone of influence up to which the effect of plume would extend. Second, to estimate the cumulative maximum concentration of heavy metals that can potentially occur in ambient atmosphere of a given yard. The cumulative maximum heavy metal concentration was predicted by the model to be between 113 μg/Nm 3 and 428 μg/Nm 3 (at 4 m/s and 1 m/s near-ground wind speeds, respectively). For example, centerline concentrations of lead (Pb) in the yard could be placed between 8 and 30 μg/Nm 3 . These estimates are much higher than the Indian National Ambient Air Quality Standards (NAAQS) for Pb (0.5 μg/Nm 3 ). This research has already become the critical science and technology inputs for formulation of policies for eco-friendly dismantling of ships, formulation of ideal procedure and corresponding health, safety, and environment provisions. The insights obtained from this research are also being used in developing appropriate technologies for minimizing exposure to workers and minimizing possibilities of causing heavy metal pollution in the intertidal zone of ship recycling yards in India. -- Highlights

Washing water treatment process for UF_6 cylinder by adjusting evaporation technology in a low temperature and low pressure

International Nuclear Information System (INIS)

Kim, Ki-tae; Ju, Young-jong; Cho, Nam-chan; Kim, Yun-kwan; Jin, Chang-suk

2016-01-01

The liquid waste is treated in this procedure; 1) Add NaOH to the liquid waste and filter the mixture with a screen. 2) Screened residue is dried and then stored in a uranium storage. 3) liquid part is moved to a storage tank and radioactivity is measured in the liquid. 5) If the concentration of radioactivity is lower than corresponding regulation limit, the liquid moved to a reaction tank and evaporated with additional low concentration HF in 105℃. 6) Radioactivity of distillate is measured and the value is lower than regulation, it is treated with a thermal decomposition process and discharged to the atmosphere in gas state. 7) Solid waste produced in the evaporation step is managed as solid nuclear waste. The treatment procedure mentioned above has disadvantageous points, producing large amount of solid waste as well as, high energy and chemical consumption. In this study, liquid waste from a real scaled cylinder wash process is applied to evaporation system to confirm feasibility of the application of evaporation and, to reduce waste production and energy consumption. Liquid radioactive wastewater from a real scaled UF6 cylinder wash process was applied to evaporation treatment system. Radioactive concentration in gross alpha was removed 99.9% in the evaporation system. And the concentration in distillate was lower than the discharge regulation. Removal of U-235 was 99.9% in the process. And 15 other kinds of radionuclides in the raw wastewater were removed completely. Secondary waste production of the evaporation system is 15g/L

Criticality concerns in cleaning large uranium hexafluoride cylinders

International Nuclear Information System (INIS)

Sheaffer, M.K.; Keeton, S.C.; Lutz, H.F.

1995-06-01

Cleaning large cylinders used to transport low-enriched uranium hexafluoride (UF 6 ) presents several challenges to nuclear criticality safety. This paper presents a brief overview of the cleaning process, the criticality controls typically employed and their bases. Potential shortfalls in implementing these controls are highlighted, and a simple example to illustrate the difficulties in complying with the Double Contingency Principle is discussed. Finally, a summary of recommended criticality controls for large cylinder cleaning operations is presented

Lift and Drag on Cylinder of Octagonal Cross-Section in a Turbulent Stream

Directory of Open Access Journals (Sweden)

Md. Jomir Hossain

2013-12-01

Full Text Available An experimental investigation of surface static pressure distributions on octagonal cylinder in uniform and turbulent flows was carried out. The study was performed on both the single cylinder and the group of two cylinders, two cylinders were used, one was at the upstream side, and the other was at the downstream side of the flow. They were placed centrally along the flow direction. The inter-spacing space between the two cylinders was varied at 1D, 2D, 3D, 4D, 5D, 6D, 7D and 8D, where D is the width of the cylinder across the flow direction. The pressure coefficients were calculated from the measured values of the surface static pressure distribution on the cylinder. Then the drag and lift coefficients were obtained from the pressure coefficients by the numerical integration method. It was observed that at various angles of attack, the values of the lift coefficients and drag coefficients were insignificant compared to those for a sharp-edged square cylinder. The strength of the vortex shedding was shown to be reduced as the intensity of the incident turbulence was increased. Measurements of drag at various angles of attack (0° to 40° showed that with increase in turbulence level the minimum drag occurred at smaller values of angle of attack.

THE INTERACTION OF A COLD ATOMISED SPRAY WITH A CIRCULAR CYLINDER

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A. AROUSSI

2010-09-01

Full Text Available The development of non-intrusive diagnostic techniques has significantly increased with the introduction of lasers. Laser based anemometry, such as Laser Doppler (LDA, Phase Doppler (PDA, and Particle Image Velocimetery (PIV can provide an accurate description of flows without interference. This study determines experimentally the fluid motion resulting from the interaction of a liquid spray with a circular cylinder. Two experimental settings were examined: the first is a discharging spray into free air and the second is a spray impinging on a circular cylinder placed 25 cylinder diameters downstream of the nozzle. These sprays were quantified using PIV. A non-intrusive droplet sizing technique was used to characterise the spray. This has shown that, within the spray, the average droplet diameter increases when the circular cylinder is introduced and so does the frequency of occurrence of these large droplets. In the wake behind the cylinder, the smaller droplets were quickly entrained and recirculated, while the larger droplets continued in the general direction of the spray cone.

78 FR 36545 - Notice of Ability To Pay-Cash-out Settlement Agreement for the Jefferson City Residential Yards...

Science.gov (United States)

2013-06-18

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9824-4] Notice of Ability To Pay--Cash-out Settlement... payment of certain response costs incurred at the Jefferson City Residential Yards Site in Jefferson City... portion of the past costs expended at the Site. Payment shall be made in 35 installments of $2,500 per...

Cylinder components properties, applications, materials

CERN Document Server

2016-01-01

Owing to the ever-increasing requirements to be met by gasoline and diesel engines in terms of CO2 reduction, emission behavior, weight, and service life, a comprehensive understanding of combustion engine components is essential today. It is no longer possible for professionals in automotive engineering to manage without the corresponding expertise, whether they work in the field of design, development, testing, or maintenance. This technical book provides in-depth answers to questions about design, production, and machining of cylinder components. In this second edition, every section has been revised and expanded to include the latest developments in the combustion engine. Content Piston rings Piston pins and piston pin circlips Bearings Connecting rods Crankcase and cylinder liners Target audience Engineers in the field of engine development and maintenanceLecturers and students in the areas of mechanical engineering, engine technology, and vehicle constructionAnyone interested in technology Publisher MAH...

Development of Flexible Pneumatic Cylinder with Built-in Flexible Linear Encoder and Flexible Bending Sensor

Science.gov (United States)

Akagi, Tetsuya; Dohta, Shujiro; Matsushita, Hisashi; Fukuhara, Akimasa

The purpose of this study is to develop a lightweight and intelligent soft actuator which can be safely attached to the human body. A novel flexible pneumatic cylinder that can be used even if it is deformed by external force had been proposed. The cylinder can realize both pushing and pulling motions even if the cylinder bends. In this paper, a flexible pneumatic cylinder with a built-in flexible linear encoder is proposed and tested. The encoder can detect the cylinder displacement even if the cylinder bends. In the next step, to realize an intelligent flexible cylinder, it is essential to recognize the angle of deflection of the cylinder to estimate the direction of the external force. Therefore, a flexible bending sensor that can measure the directional angle by attaching it to the end of the cylinder is also proposed and tested. The tested bending sensor also consists of four inexpensive photo-reflectors set on the circumferential surface to the cylinder tube every 90 degrees from the center of the tube. By measuring the distance between the photo reflector and the surface of the tube at each point, the bending directional angle of the cylinder can be obtained. A low cost measuring system using a micro-computer incorporating a programmed Up/Down counter to measure the displacement of the cylinder is also developed. As a result, it was confirmed that the measuring accuracy of the bending directional angle was good, less than 0.7 degrees as a standard deviation.

Effect of plasma actuator and splitter plate on drag coefficient of a circular cylinder

Science.gov (United States)

Akbıyık, Hürrem; Erkan Akansu, Yahya; Yavuz, Hakan; Ertuğrul Bay, Ahmet

2016-03-01

In this paper, an experimental study on flow control around a circular cylinder with splitter plate and plasma actuator is investigated. The study is performed in wind tunnel for Reynolds numbers at 4000 and 8000. The wake region of circular cylinder with a splitter plate is analyzed at different angles between 0 and 180 degrees. In this the study, not only plasma actuators are activated but also splitter plate is placed behind the cylinder. A couple electrodes are mounted on circular cylinder at ±90 degrees. Also, flow visualization is achieved by using smoke wire method. Drag coefficient of the circular cylinder with splitter plate and the plasma actuator are obtained for different angles and compared with the plain circular cylinder. While attack angle is 0 degree, drag coefficient is decreased about 20% by using the splitter plate behind the circular cylinder. However, when the plasma actuators are activated, the improvement of the drag reduction is measured to be 50%.

Shear-induced autorotation of freely rotatable cylinder in a channel flow at moderate Reynolds number

Science.gov (United States)

Xia, Yi; Lin, Jianzhong; Ku, Xiaoke; Chan, Tatleung

2018-04-01

Flow past a center-pinned freely rotatable cylinder asymmetrically confined in a two-dimensional channel is simulated with the lattice Boltzmann method for a range of Reynolds number 0.1 ≤ Re ≤ 200, eccentricity ratio 0/8 ≤ ɛ ≤ 7/8, and blockage ratio 0.1 ≤ β ≤ 0.5. It is found that the inertia tends to facilitate the anomalous clockwise rotation of the cylinder. As the eccentricity ratio increases, the cylinder rotates faster in the counterclockwise direction and then slows down at a range of Re 40, there exists an anomalous clockwise rotation for the cylinder at a low eccentricity ratio and the domain where the cylinder rotates anomalously becomes larger with the increase in the Reynolds number. In a channel with a higher blockage ratio, the rotation of the cylinder is more sensitive to the change of cylinder lateral position, and the separatrix at which the cylinder remains a state of rest moves upward generally. The cylinder is more likely to rotate counterclockwise and the rotating velocity is larger. At a lower blockage ratio, the anomalous clockwise rotation is more likely to occur, and the largest rotating velocity occurs when the blockage ratio is equal to 0.3. The mechanism of distinct rotational behavior of the cylinder is attributed to the transformation of distribution of shear stress which is resulted from the variation of pressure drop, the shift of maximum or minimum pressure zones along the upper and lower semi-cylinder surface, and the movement of stagnant point and separate point. Finally, the effects of the cylinder rotation on the flow structure and hydrodynamic force exerted on the cylinder surface are analyzed as well.

Online Condition Monitoring of Gripper Cylinder in TBM Based on EMD Method

Science.gov (United States)

Li, Lin; Tao, Jian-Feng; Yu, Hai-Dong; Huang, Yi-Xiang; Liu, Cheng-Liang

2017-11-01

The gripper cylinder that provides braced force for Tunnel Boring Machine (TBM) might fail due to severe vibration when the TBM excavates in the tunnel. Early fault diagnosis of the gripper cylinder is important for the safety and efficiency of the whole tunneling project. In this paper, an online condition monitoring system based on the Empirical Mode Decomposition (EMD) method is established for fault diagnosis of the gripper cylinder while TBM is working. Firstly, the lumped mass parameter model of the gripper cylinder is established considering the influence of the variable stiffness at the rock interface, the equivalent stiffness of the oil, the seals, and the copper guide sleeve. The dynamic performance of the gripper cylinder is investigated to provide basis for its health condition evaluation. Then, the EMD method is applied to identify the characteristic frequencies of the gripper cylinder for fault diagnosis and a field test is used to verify the accuracy of the EMD method for detection of the characteristic frequencies. Furthermore, the contact stiffness at the interface between the barrel and the rod is calculated with Hertz theory and the relationship between the natural frequency and the stiffness varying with the health condition of the cylinder is simulated based on the dynamic model. The simulation shows that the characteristic frequencies decrease with the increasing clearance between the barrel and the rod, thus the defects could be indicated by monitoring the natural frequency. Finally, a health condition management system of the gripper cylinder based on the vibration signal and the EMD method is established, which could ensure the safety of TBM.

Force Control for a Pneumatic Cylinder Using Generalized Predictive Controller Approach

OpenAIRE

Mohd Faudzi, Ahmad ’Athif; Mustafa, Nu’man Din; Osman, Khairuddin

2014-01-01

Pneumatic cylinder is a well-known device because of its high power to weight ratio, easy use, and environmental safety. Pneumatic cylinder uses air as its power source and converts it to a possible movement such as linear and rotary movement. In order to control the pneumatic cylinder, controller algorithm is needed to control the on-off solenoid valve with encoder and pressure sensor as the feedback inputs. In this paper, generalized predictive controller (GPC) is proposed as the control st...

Mechanism of drag reduction for circular cylinders with patterned surface

International Nuclear Information System (INIS)

Butt, U.; Jehring, L.; Egbers, C.

2014-01-01

Highlights: • Reduced drag of patterned cylinders over a wide range of Re numbers. • Hexagonal patterns cannot be characterized as roughness structures. • Hexagonal bumps affect the flow like spherical dimples of smaller k/d ratio do. • Main separation is delayed caused by a partial separation. • Angle of a separation line is not constant over the length of cylinder. -- Abstract: In this paper, the flow over cylinders with a patterned surface (k/d = 1.98 × 10 −2 ) is investigated in a subsonic wind tunnel over Reynolds numbers ranging from 3.14 × 10 4 to 2.77 × 10 5 by measuring drag, flow visualization and measuring velocity profiles above the surface of the cylinders, to observe the effect of hexagonal patterns on the flow of air. These patterns can also be referred as hexagonal dimples or bumps depending on their configuration. The investigations revealed that a patterned cylinder with patterns pressed outwards has a drag coefficient of about 0.65 times of a smooth one. Flow visualization techniques including surface oil-film technique and velocity profile measurement were employed to elucidate this effect, and hence present the mechanism of drag reduction. The measurement of velocity profiles using hot-wire anemometry above the surface reveal that a hexagonal bump cause local separation generating large turbulence intensity along the separating shear layer. Due to this increased turbulence, the flow reattaches to the surface with higher momentum and become able to withstand the pressure gradient delaying the main separation significantly. Besides that, the separation does not appear to occur in a straight line along the length of the cylinder as in case of most passive drag control methods, but follow exactly the hexagonal patterns forming a wave with its crest at 115° and trough at 110°, in contrast to the laminar separation line at 85° for a smooth cylinder

Experimental research of the yielding behavior of a graphite cylinder subjected to line loading

International Nuclear Information System (INIS)

Liu Hetong; Ma Qinwei; Ma Shaopeng; Wang Hongtao

2014-01-01

The graphite material cylinders are widely used in High-temperature gas-cooled reactor as connecting components. For engineering design, the deformation behavior, especially the yielding process of the graphite cylinder should be investigated in order to evaluate the carrying capacity of the cylinder. The yielding formation and propagation of a graphite cylinder subjected to line loading, which corresponds to the global behavior of the structure, was experimentally studied and evaluated by measuring the strain fields on the end of the cylinder using Digital Image Correlation. The global behavior of the structure is expressed by a relationship between the average stress (load divided by contact area) and the equivalent strain (ratio of half width of contact area to radius of the cylinder), the contact area was measured by identifying the color area of the pressure film in a new experiment which graphite component is loaded and unloaded continuously. A correspondence between the yielding state and the nonlinearity of the global behavior was constructed, as loading was increased, the cylinder was found to first yield at a specific point after which a yielding core formed and propagated. Before the yielding core propagated to the surface of the cylinder, the global behavior of the structure remained linear. After the yielding core propagated to the surface of the cylinder, the global behavior became nonlinear. The correspondence constructed in the paper will be helpful to understand the failure process and to evaluate the carrying capacity of a graphite cylinder subjected to line loading in reactors. (author)

Experimental Study on Natural Convection Heat Transfer From two Parallel Horizontal Cylinders in Horizontal Cylindrical Enclosure

Directory of Open Access Journals (Sweden)

Ahmed T. Ahmed

2013-05-01

Full Text Available  An experimental study on natural convection heat transfer from two parallel horizontal cylinders in horizontal cylindrical enclosure was carried out under condition of constant surfaces temperature for two cylinders and cylindrical enclosure. The study included the effect of Rayleigh number, rotation angle that represent the confined angle between the passing horizontal plane in cylindrical enclosure center and passing line in two cylinders centers, and the spaces between two cylinders on their heat loss ability.39An experimental set-up was used for this purpose which consist watercontainer, test section which is formed of plastic cylinder that represent the cylindrical enclosure, and two heating elements which are formed of two copper cylinders with (19 mm in diameters heated internally by electrical sources that represents transfer and heat loss elements through this set-up.      The experiments were done at the range of Rayleigh number between ( , cylinders rotation angle at ( , and spacing ratio at ( .     The study showed that the ability of heat loss from two cylinders is a function of Rayleigh number, cylinders rotation angle, and the spaces between them. This ability is increased by increasing of Rayleigh number and it was showed that this ability reaches maximum value at the first cylinder ( and minimum value at the second cylinder ( at spacing ratio (S/D=3 and rotation angle ( for the first and ( for the second cylinder respectively.      The effective variables on natural convection heat transfer from the above two cylinders are related by two correlating equations, each one explains dimensionless relation of heat transfer from each cylinder that represented by Nusselt number against Rayleigh number, rotation angle, and the spacing ratio between two cylinders. 

Effect of the expansion associated with the plutonium α-β-γ phase transitions on storage can integrity

Science.gov (United States)

Spearing, Dane R.; Veirs, D. Kirk; Prenger, F. Coyne

2001-11-01

The effects of the volume expansion of plutonium metal through the α-β and β-γ phase transitions on a stainless steel storage container were examined. A cylindrical plutonium ingot was placed in the axial center of an annealed stainless steel cylinder and thermally cycled until a steady state in the strain response of the cylinder was reached. The average plastic hoop strain was 1.47% and 1.55% after six and four cycles through the α-β and α-β-γ phase transitions, respectively. Elastic strain was ˜0.2%, indicating a 8.96 MPa back pressure on the Pu ingot. This is an order of magnitude less than the compressive yield strength of α- and β-Pu at the transition temperature. Metallographic analyses indicate that anisotropic expansion of the Pu ingot is due to preferentially oriented grain growth of the β-Pu along the axial direction due to stress applied by the steel cylinder during the α-β phase transition.

ENTREPRENEURIAL OPPORTUNITIES IN FOOD PROCESSING UNITS (WITH SPECIAL REFERENCES TO BYADGI RED CHILLI COLD STORAGE UNITS IN THE KARNATAKA STATE

Directory of Open Access Journals (Sweden)

P. ISHWARA

2010-01-01

Full Text Available After the green revolution, we are now ushering in the evergreen revolution in the country; food processing is an evergreen activity. It is the key to the agricultural sector. In this paper an attempt has been made to study the workings of food processing units with special references to Red Chilli Cold Storage units in the Byadgi district of Karnataka State. Byadgi has been famous for Red Chilli since the days it’s of antiquity. The vast and extensive market yard in Byadagi taluk is famous as the second largest Red Chilli dealing market in the country. However, the most common and recurring problem faced by the farmer is inability to store enough red chilli from one harvest to another. Red chilli that was locally abundant for only a short period of time had to be stored against times of scarcity. In recent years, due to Oleoresin, demand for Red Chilli has grow from other countries like Sri Lanka, Bangladesh, America, Europe, Nepal, Indonesia, Mexico etc. The study reveals that all the cold storage units of the study area have been using vapour compression refrigeration system or method. All entrepreneurs have satisfied with their turnover and profit and they are in a good economic position. Even though the average turnover and profits are increased, few units have shown negligible amount of decrease in turnover and profit. This is due to the competition from increasing number of cold storages and early established units. The cold storages of the study area have been storing Red chilli, Chilli seeds, Chilli powder, Tamarind, Jeera, Dania, Turmeric, Sunflower, Zinger, Channa, Flower seeds etc,. But the 80 per cent of the each cold storage is filled by the red chilli this is due to the existence of vast and extensivered chilli market yard in the Byadgi. There is no business without problems. In the same way the entrepreneurs who are chosen for the study are facing a few problems in their business like skilled labour, technical and management

Heat convection in a set of three vertical cylinders

International Nuclear Information System (INIS)

Serrano Ramirez, M.L. de.

1993-01-01

Experimental results on temperature and heat flow in a set of three vertical cylinders with internal generation of heat, water submerged and in free convection are presented in this work . Temperature distribution, Nusselt number and convective coefficient (h) for each rod, developed for the distance between the axis of cylinders in vertical position, as a consequence of the application of power in its outside, are analyzed. Experimental information about heat transfer by free convection in vertical cylinders and surfaces is analyzed. Information of the several author who have carried out studies about the heat transfer on vertical cylinders was compiled, and the proposed equations with the experimental data obtained in the thermo fluids laboratory of National Institute of Nuclear Research (ININ) were tested. The way in which separation distance, s, distribution temperature array, Nusselt number, and convective coefficient calculated for the proposed channel with the Keyhani, Dutton and experimental equations are tabulated and they are plotted for each power value and for each separation between rods. The scheme of the used equipment and the experimentation description as well as the observations of tests and graphical results are included. (Author)

Development of free surface flow between concentric cylinders with vertical axes

International Nuclear Information System (INIS)

Watanabe, T; Toya, Y; Nakamura, I

2005-01-01

Numerical and experimental studies are conducted on flows developing between two concentric cylinders with vertical axes. The inner cylinder rotates and the outer and the lower end wall are fixed. The upper boundary is a free surface. The flow is at rest in an initial state, and the inner cylinder impulsively begins to rotate or its rotation speed linearly increases to a prescribed value. The acceleration rate of the inner cylinder changes the formation processes of flows and/or the final flow modes. Time-dependent flows appear at higher Reynolds numbers, and the numerical and experimental results of the power spectra show some agreements. It is suggested that critical Reynolds numbers appear, at which the fluctuations in the displacement of the free surface and the kinetic energy of a velocity component steeply increase

Disk-cylinder method for using NMR to measure magnetic susceptibility

International Nuclear Information System (INIS)

Burnham, A.K.

1978-01-01

The sphere-cylinder method of using nuclear magnetic resonance (NMR) to measure the magnetic susceptibility of diamagnetic and paramagnetic materials has been generalized to the disk-cylinder method. A two-fold increase in sensitivity was obtained. Accuracies of 0.1% of the diamagnetism of water should be readily obtainable

High Reynolds number oscillations of a circular cylinder

OpenAIRE

Hirata, Miguel H.; Pereira, Luiz Antonio A.; Recicar, Jan N.; Moura, Washington H. de

2008-01-01

This paper concerns the numerical simulation of the flow around an oscillating circular cylinder, which moves with constant velocity in a quiescent Newtonian fluid with constant properties. For each time step of the simulation a number of discrete Lamb vortices is placed close to the body surface; the intensity of each of these is determined such as to satisfy the no-slip boundary condition. The aerodynamic loads acting on the surface of cylinder are computed using the integral formulation de...

Large eddy simulation of the subcritical flow over a V grooved circular cylinder

International Nuclear Information System (INIS)

Alonzo-García, A.; Gutiérrez-Torres, C. del C.; Jiménez-Bernal, J.A.

2015-01-01

Highlights: • We compared numerically the turbulent flow over a smooth circular cylinder and a V grooved cylinder in the subcritical regime. • Turbulence intensities in both streamwise and normal direction suffered attenuations. • The swirls structures on grooves peaks seemed to have a cyclic behavior. • The evolution of the flow inside grooves showed that swirls structures located in peaks suffered elongations in the normal direction. • The secondary vortex structures formed in the grooved cylinder near wake were smaller in comparison of the smooth cylinder flow. - Abstract: In this paper, a comparative numerical study of the subcritical flow over a smooth cylinder and a cylinder with V grooves (Re = 140,000) is presented. The implemented technique was the Large Eddy Simulation (LES), which according to Kolmogorov's theory, resolves directly the most energetic largest eddies and models the smallest and considered universal high frequency ones. The Navier-Stokes (N-S) equations were solved using the commercial software ANSYS FLUENT V.12.1, which applied the finite volume method (FVM) to discretize these equations in their unsteady and incompressible forms. The grid densities were 2.6 million cells and 13.5 million cells for the smooth and V grooved cylinder, respectively. Both meshes were composed of structured hexahedral cells and close to the wall of the cylinders, additional refinements were employed in order to obtain y +<5 values. All cases were simulated during at least 15 vortex shedding cycles with the aim of obtaining significant statistical data. Results: showed that for both cases (smooth and V grooved cylinder flow), the numerical code was capable of reproducing the most important physical quantities of the subcritical regime. Velocity distribution and turbulence intensity in the flow direction suffered a slight attenuation along the wake, as a consequence of grooves perturbation, which also caused an increase in the pressure coefficient

Bee Fauna and Floral Abundance Within Lawn-Dominated Suburban Yards in Springfield, MA.

Science.gov (United States)

Lerman, S B; Milam, J

2016-09-01

Private yards comprise a significant component of urban lands, with managed lawns representing the dominant land cover. Lawns blanket > 163,000 km 2 of the United States, and 50% of urban and suburban areas. When not treated with herbicides, lawns have the capacity to support a diversity of spontaneous (e.g., not planted) flowers, with the potential to provide nectar and pollen resources for pollinators such as native bees. In order to determine the extent to which suburban lawns support these important species, we surveyed lawns in 17 suburban yards in Springfield, MA, between May and September 2013 and 2014. Householders participating in the study did not apply chemical pesticides or herbicides to lawns for the duration of the study. We collected 5,331 individual bees, representing 111 species, and 29% of bee species reported for the state. The majority of species were native to North America (94.6%), nested in soil (73%), and solitary (48.6%). Species richness was lower for oligolectic (specialists on a single plant; 9.9%) and parasitic species (12.6%). Abundance percentages for number of individuals were similar. We documented 63 plant species in the lawns, the majority of which were not intentionally planted. The most abundant lawn flowers were dandelion ( Taraxacum officinale ) and clover ( Trifolium sp. ). Nearly 30% of the spontaneous plant species growing in the lawns were native to North America. Our study suggests that the spontaneous lawn flowers could be viewed as supplemental floral resources and support pollinators, thereby enhancing the value of urban green spaces.

Pulsatility role in cylinder flow dynamics at low Reynolds number

KAUST Repository

Qamar, Adnan

2012-01-01

We present dynamics of pulsatile flow past a stationary cylinder characterized by three non-dimensional parameters: the Reynolds number (Re), non-dimensional amplitude (A) of the pulsatile flow velocity, and Keulegan-Carpenter number (KC = Uo/Dωc). This work is motivated by the development of total artificial lungs (TAL) device, which is envisioned to provide ambulatory support to patients. Results are presented for 0.2 ≤ A ≤ 0.6 and 0.57 ≤ KC ≤ 2 at Re = 5 and 10, which correspond to the operating range of TAL. Two distinct fluid regimes are identified. In both regimes, the size of the separated zone is much greater than the uniform flow case, the onset of separation is function of KC, and the separation vortex collapses rapidly during the last fraction of the pulsatile cycle. The vortex size is independent of KC, but with an exponential dependency on A. In regime I, the separation point remains attached to the cylinder surface. In regime II, the separation point migrates upstream of the cylinder. Two distinct vortex collapse mechanisms are observed. For A < 0.4 and all KC and Re values, collapse occurs on the cylinder surface, whereas for A > 0.4 the separation vortex detaches from the cylinder surface and collapses at a certain distance downstream of the cylinder. The average drag coefficient is found to be independent of A and KC, and depends only on Re. However, for A > 0.4, for a fraction of the pulsatile cycle, the instantaneous drag coefficient is negative indicating a thrust production. © 2012 American Institute of Physics.

Longitudinal Weld Land Buckling in Compression-Loaded Orthogrid Cylinders

Science.gov (United States)

Thornburgh, Robert P.; Hilburger, Mark W.

2010-01-01

Large stiffened cylinders used in launch vehicles (LV), such as the Space Shuttle External Tank, are manufactured by welding multiple curved panel sections into complete cylinders. The effects of the axial weld lands between the panel sections on the buckling load were studied, along with the interaction between the acreage stiffener arrangement and the weld land geometry. This document contains the results of the studies.

Mixed convection of ferrofluids in a lid driven cavity with two rotating cylinders

Directory of Open Access Journals (Sweden)

Fatih Selimefendigil

2015-09-01

Full Text Available Mixed convection of ferrofluid filled lid driven cavity in the presence of two rotating cylinders were numerically investigated by using the finite element method. The cavity is heated from below, cooled from driven wall and rotating cylinder surfaces and side vertical walls of the cavity are assumed to be adiabatic. A magnetic dipole source is placed below the bottom wall of the cavity. The study is performed for various values of Reynolds numbers (100 ≤ Re ≤ 1000, angular rotational speed of the cylinders (−400 ≤ Ω ≤ 400, magnetic dipole strengths (0 ≤ γ ≤ 500, angular velocity ratios of the cylinders (0.25≤Ωi/Ωj≤4 and diameter ratios of the cylinders (0.5≤Di/Dj≤2. It is observed that flow patterns and thermal transport within the cavity are affected by variation in Reynolds number and magnetic dipole strength. The results of this investigation revealed that cylinder angular velocities, ratio of the angular velocities and diameter ratios have profound effect on heat transfer enhancement within the cavity. Averaged heat transfer enhancements of 181.5 % is achieved for clockwise rotation of the cylinder at Ω = −400 compared to motionless cylinder case. Increasing the angular velocity ratio from Ω2/Ω1=0.25 to Ω2/Ω1=4 brings about 91.7 % of heat transfer enhancement.

Root cause analysis of the fatigue failures of the pulsation dampers of a large underground gas storage (UGS) system

NARCIS (Netherlands)

Eijk, A.; Lange, D. de; Maljaars, J.; Tenbrock-Ingenhorst, A.; Gottmer, A.

2014-01-01

Two large identical 6-cylinder Ariel JGB/6 reciprocating compressors each of 7.5 MW, are used for an underground gas storage system (UGS) plant of RWE Gasspeicher GmbH located in Epe, Germany. The system is in operation since 2005. In 2011 several internals parts (baffle plates and baffle choke

Effect of slip on vortex dynamics and forcing of a superhydrophobic cylinder

Science.gov (United States)

Muralidhar, Pranesh; Daniello, Robert; Ferrer, Nangelie; Rothstein, Jonathan

2011-11-01

Superhydrophobic surfaces have been shown to produce significant drag reduction for both laminar and turbulent flows of water through large and small-scale channels. In this presentation, a series of experiments will be presented which investigate the effect of superhydrophobic-induced slip on the vortex dynamics in the wake of a cylinder and the change in the drag and lift forces thereof. In these experiments, circular cylinders are coated with a series of superhydrophobic surfaces fabricated from PDMS with well-defined micron-sized patterns of surface roughness. Using force measurements and PIV (Particle Image Velocimetry), we will show that these surfaces have a noticeable effect on the drag/lift and vortex dynamics of cylinders. When compared to a smooth, no-slip cylinder, we will show that the lift/drag and the amount of raw vorticity that is shed in the wake of the superhydrophobic cylinder decreases. In addition, we will show that the forcing is sensitive to changes of feature spacing, size and orientation.

Research on torsional vibration modelling and control of printing cylinder based on particle swarm optimization

Science.gov (United States)

Wang, Y. M.; Xu, W. C.; Wu, S. Q.; Chai, C. W.; Liu, X.; Wang, S. H.

2018-03-01

The torsional oscillation is the dominant vibration form for the impression cylinder of printing machine (printing cylinder for short), directly restricting the printing speed up and reducing the quality of the prints. In order to reduce torsional vibration, the active control method for the printing cylinder is obtained. Taking the excitation force and moment from the cylinder gap and gripper teeth open & closing cam mechanism as variable parameters, authors establish the dynamic mathematical model of torsional vibration for the printing cylinder. The torsional active control method is based on Particle Swarm Optimization(PSO) algorithm to optimize input parameters for the serve motor. Furthermore, the input torque of the printing cylinder is optimized, and then compared with the numerical simulation results. The conclusions are that torsional vibration active control based on PSO is an availability method to the torsional vibration of printing cylinder.

Transient Simulation of a Rotating Conducting Cylinder in a Transverse Magnetic Field

Science.gov (United States)

2016-09-01

the boundary conditions and magnetic field excitation. The balloon (no fringing at infinity ) boundary condition is used for the model. Two magnetic...cylinder to study the effects of the magnetic responses of the cylinder in the time history . Table 1 summarizes the electromagnetic properties of the...and phase shift angles of the magnetic flux density in the time history , at the center of the structural steel, aluminum, and copper cylinder

On the motion of a compressible fluid in a rotating cylinder

International Nuclear Information System (INIS)

Brouwers, J.J.H.

1976-06-01

The secondary flow of an incompressible fluid or a perfect gas in a rotating cylinder is taken as a small perturbation on the isothermal state of rigid body rotation. Three types of flow are identified by increasing length-to-radius ratio L. These correspond to Esup(1/2) -1 and E -1 approximately L, where E is the Ekman number based on the radius and taken to be small. In the first range a geostrophic flow in the interior extended by Ekman layers near the end caps and Stewartson layers near the cylinder wall is found. For L approximately Esup(-1/2) and L approximately E -1 both Stewartson layers successively expand to the interior. For L approximately> E -1 radial diffusion of momentum is an important parameter describing the flow in the main section of the cylinder. For the perfect gas, special attention is focussed on strong radial density gradients. The modified Ekman number Esub(m) based on the density at the cylinder wall and on the density scale height is taken to be small. Increasing the ratio of the length to the radial density scale height Lsub(m) again three types of flow are distinguished. These correspond to Esub(m)sup(1/2) -1 and Esub(m)sup(-1) approximately Lsub(m). Compared to the incompressible fluid, two essential differences are found. (i) An inviscid flow characteristic for the first range is only observed in a limited region near the cylinder wall. Diffusive processes are important in the core of the cylinder. (ii) A change of the flow type appears when both Stewartson layers successively expand over the small radial density scale height. Diffusive regions come up from the centre of the cylinder and join. A change of the flow type appears at relatively small values of L. The theory discusses the efficiency of gas ultracentrifuges for isotope separation

Mass transfer behavior of rotating square cylinder electrochemical reactor in relation to wastewater treatment

International Nuclear Information System (INIS)

Abdel-Aziz, M.S.M.; El-Shazly, A.H.; Farag, H.A.; Sedahmed, G.H.

2011-01-01

Highlights: → The work explores a new electrochemical reactor by using square rotating cylinders. → The results show that it is superior to the traditional circular rotating cylinder. → A dimensionless design equation for the new reactor was correlated. → The oxalic acid removal by the new reactor was succeeded and found promising. → The energy consumption per kg oxalic acid removed by the unit was calculated. - Abstract: Rates of mass transfer at a rotating square cylinder were measured by an electrochemical technique which involved measuring the limiting current of the cathodic reduction of K 3 Fe(CN) 6 in a large excess of NaOH solution. Variables studied were: cylinder rotation speed, physical properties of the solution and cylinder equivalent diameter. The data for the condition 1577 0.33 Re 0.45 For a given set of conditions the rate of mass transfer at the square rotating cylinder was found to be higher than that at the traditional circular rotating cylinder by an amount ranging from 47% to 200% depending on Re. The use of the square rotating cylinder electrode in removing oxalic acid from wastewater by anodic oxidation on Pb/PbO anode was examined and found to be promising.

Reduction of sound transmission across plenum windows by incorporating an array of rigid cylinders

Science.gov (United States)

Tang, S. K.

2018-02-01

The potential improvement of plenum window noise reduction by installing rigid circular cylinder arrays into the window cavity is investigated numerically using the finite-element method in this study. A two-dimensional approach is adopted. The sound transmission characteristics and propagation within the plenum window are also examined in detail. Results show that the installation of the cylinders in general gives rise to broadband improvement of noise reduction across a plenum window regardless of the direction of sound incidence. Such acoustical performance becomes better when more cylinder columns are installed, but it is suggested that the number of cylinder rows should not exceed two. Results also show that the cylinder positions relative to the nodal/anti-nodal planes of the acoustic modes are crucial in the noise reduction enhancement mechanisms. Noise reduction can further be enhanced by staggering the cylinder rows, such that each cylinder row supports the development of a different acoustic mode. For the simple cylinder arrangements considered in this study, the traffic noise reduction enhancement observed in this study can be as high as 4-5 dB, which is already comparable to or higher than the maximum achieved by installing sound absorption into a plenum window.

Energy Loss, Velocity Distribution, and Temperature Distribution for a Baffled Cylinder Model, Special Report

Science.gov (United States)

Brevoort, Maurice J.

1937-01-01

In the design of a cowling a certain pressure drop across the cylinders of a radial air-cooled engine is made available. Baffles are designed to make use of this available pressure drop for cooling. The problem of cooling an air-cooled engine cylinder has been treated, for the most part, from considerations of a large heat-transfer coefficient. The knowledge of the precise cylinder characteristics that give a maximum heat-transfer coefficient should be the first consideration. The next problem is to distribute this ability to cool so that the cylinder cools uniformly. This report takes up the problem of the design of a baffle for a model cylinder. A study has been made of the important principles involved in the operation of a baffle for an engine cylinder and shows that the cooling can be improved 20% by using a correctly designed baffle. Such a gain is as effective in cooling the cylinder with the improved baffle as a 65% increase in pressure drop across the standard baffle and fin tips.

Failure Analysis of a Modern High Performance Diesel Engine Cylinder Head

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Bingbin Guo

2014-05-01

Full Text Available This paper presents a failure analysis on a modern high performance diesel engine cylinder head made of gray cast iron. Cracks appeared intensively at the intersection of two exhaust passages in the cylinder head. The metallurgical examination was conducted in the crack origin zone and other zones. Meanwhile, the load state of the failure part of the cylinder head was determined through the Finite Element Analysis. The results showed that both the point of the maximum temperature and the point of the maximum thermal-mechanical coupling stress were not in the crack position. The excessive load was not the main cause of the failure. The large cooling rate in the casting process created an abnormal graphite zone that existed below the surface of the exhaust passage (about 1.1 mm depth, which led to the fracture of the cylinder head. In the fractured area, there were a large number of casting defects (dip sand, voids, etc. and inferior graphite structure (type D, type E which caused stress concentration. Moreover, high temperature gas entered the cracks, which caused material corrosion, material oxidization, and crack propagation. Finally, premature fracture of the cylinder head took place.

Buckling Response of a Large-Scale, Seamless, Orthogrid-Stiffened Metallic Cylinder

Science.gov (United States)

Rudd, Michelle Tillotson; Hilburger, Mark W.; Lovejoy, Andrew E.; Lindell, Michael C.; Gardner, Nathaniel W.; Schultz, Marc R.

2018-01-01

Results from the buckling test of a compression-loaded 8-ft-diameter seamless (i.e., without manufacturing joints), orthogrid-stiffened metallic cylinder are presented. This test was used to assess the buckling response and imperfection sensitivity characteristics of a seamless cylinder. In addition, the test article and test served as a technology demonstration to show the application of the flow forming manufacturing process to build more efficient buckling-critical structures by eliminating the welded joints that are traditionally used in the manufacturing of large metallic barrels. Pretest predictions of the cylinder buckling response were obtained using a finite-element model that included measured geometric imperfections. The buckling load predicted using this model was 697,000 lb, and the test article buckled at 743,000 lb (6% higher). After the test, the model was revised to account for measured variations in skin and stiffener geometry, nonuniform loading, and material properties. The revised model predicted a buckling load of 754,000 lb, which is within 1.5% of the tested buckling load. In addition, it was determined that the load carrying capability of the seamless cylinder is approximately 28% greater than a corresponding cylinder with welded joints.

Chlorine leak on Mumbai port trust′s Sewri yard: A case study

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Rakesh Kumar Sharma

2010-01-01

Full Text Available Chemical emergencies involving hazardous chemicals are not uncommon in India. More than 25 incidents have been identified in National Disaster Management Guidelines - Chemical (Industrial Disaster Management, released in May 2007. In a recent occurrence on the morning of 14 July 2010, nearly at 3:00 a.m., chlorine leak was reported from a gas cylinder referred as turner, weighing about 650 kg, corroding with time at the Haji Bunder hazardous cargo warehouse in Mumbai Port Trust, Sewri, affecting over 120 people in the neighborhood, including students, laborers, port workers and fire fighters, of whom 70 were reported critical. It has been observed to be a blatant case of ignorance and negligence as well as contraventions to the safety and environmental safeguard requirements under existing statues as well as non-maintenance of failsafe conditions at the site requisite for chlorine storage. The analysis revealed significant gaps in the availability of neutralization mechanism and the chlorine stored in open increased the possibility of formation of ingress mixture due to busting of chlorine filled tankers. The Government of India has institutionalized emergency preparedness framework at national, state and district level as envisaged in Disaster Management Act, 2005, to prepare the nation to mitigate such incidences, if all the preventive safety provisions fail. Ministry of Environment and Forests (MoEF is preparing National Action Plan-Chemical (Industrial Disaster Management based on National Guidelines to implement all the mechanisms of capacity development across the country.

A study on the design of a low-friction, high-speed pneumatic cylinder

International Nuclear Information System (INIS)

Kim, Do Tae; Kim, Dong Soo; Ju, Min Jin

2008-01-01

Of all of pneumatic components utilized in the make up of pneumatic circuits on either automatic assembly machine or industrial equipment, the pneumatic cylinder is more oriented toward being a structural as well as a pneumatic member. The structural design must be based to a large degree on the end of application of the cylinder on the equipment it is operating. In this paper, design studies of a double-acting pneumatic cushion type cylinder with low-friction and high-speed driving have been developed. Of interest here is to investigate the structural analysis of cylinder tube, piston rod, end cover, and to analyze the buckling of piston rod. Also, a relief valve type cushion mechanism is considered. This cushion mechanism is found to be adequate under a high-speed driving of pneumatic cylinders

Experimental vibration study of in-air and fluid coupled co-axial cylinders

International Nuclear Information System (INIS)

Chu, M.; Brown, S.; Lestingi, J.

1979-01-01

It was the objective of this study to develop and carry out an experimental program which would provide additional insight into the mechanics of fluid--solid interaction with respect to the response of a set of coaxial cylinders with water in the annulus. Such configurations are found in nuclear reactors in the vessel wall-thermal liner. The effects of cylinder thickness and the fluid filled annulus gap size on the resonant frequencies and mode shapes of the cylinders (either singly or coupled in air and a water environment) are presented in this paper; also included is an evaluation of damping for selected gaps and cylinder thicknesses. Details of the experimental setup and procedures are also outlined

Elastic torsional buckling of thin-walled composite cylinders

Science.gov (United States)

Marlowe, D. E.; Sushinsky, G. F.; Dexter, H. B.

1974-01-01

The elastic torsional buckling strength has been determined experimentally for thin-walled cylinders fabricated with glass/epoxy, boron/epoxy, and graphite/epoxy composite materials and composite-reinforced aluminum and titanium. Cylinders have been tested with several unidirectional-ply orientations and several cross-ply layups. Specimens were designed with diameter-to-thickness ratios of approximately 150 and 300 and in two lengths of 10 in. and 20 in. The results of these tests were compared with the buckling strengths predicted by the torsional buckling analysis of Chao.

Transverse magnetic scattering by parallel conducting elliptic cylinders

Science.gov (United States)

Sebak, A.

1991-10-01

A boundary value solution to the problem of transverse magnetic multiple scattering by M parallel perfectly conducting elliptic cylinders is presented. The solution is an exact one and based on the separation-of-variables technique and the addition theorem for Mathieu functions. It is expressed in terms of a system of simultaneous linear equations of infinite order, which is then truncated for numerical computations. Representative numerical results for the scattered field by two cylinders are then generated, for some selected sizes and orientations parameters, and presented.

Manual on safe production, transport, handling and storage of uranium hexafluoride

International Nuclear Information System (INIS)

1994-11-01

This document includes a description of the physical, chemical and radiological properties of UF 6 and related products, including information concerning their production, handling, storage and transportation and the management of the wastes which result. All the operations of UF 6 management are considered form a safety point of view. The IAEA organized a series of meetings to consider the hazards of UF 6 transport since considerable quantities of depleted, natural and enriched UF 6 are transported between nuclear fuel sites. Storage of depleted UF 6 is another important issue. Factors affecting long term storage are presented, especially site choice and cylinder corrosion. Other topics such as waste management, quality assurance and emergency preparedness which contribute to the overall safety of UF 6 handling, are included. The intention of this document is to provide analysis of the safety implications of all stages of UF 6 operations and to draw attention to specific features and properties of importance. 38 refs, figs, tabs

Influence of the stacking sequence of layers on the mechanical behavior of polymeric composite cylinders

International Nuclear Information System (INIS)

Carvalho, Osni de

2006-01-01

This work evaluated experimentally the influence of the stacking sequence of layers symmetrical and asymmetrical on the mechanical behavior of polymeric composite cylinders. For so much, two open-ended cylinders groups were manufactured by filament winding process, which had different stacking sequence related to the laminate midplane, characterizing symmetrical and asymmetrical laminates. The composite cylinders were made with epoxy matrix and carbon fiber as reinforcement. For evaluation of the mechanical strength, the cylinders were tested hydrostatically, which consisted of internal pressurization in a hydrostatic device through the utilization of a fluid until the cylinders burst. Additionally, were compared the strains and failure modes between the cylinders groups. The utilization of a finite element program allowed to conclude that this tool, very used in design, does not get to identify tensions in the fiber direction in each composite layer, as well as interlaminar shear stress, that appears in the cylinders with asymmetrical stacking sequence. The tests results showed that the stacking sequence had influence in the mechanical behavior of the composite cylinders, favoring the symmetrical construction. (author)

Vortex interactions in a two side-by-side cylinder near-wake

International Nuclear Information System (INIS)

Wang, Z.J.; Zhou, Y.

2005-01-01

The flow behind two side-by-side circular cylinders is experimentally investigated based on laser-illuminated flow-visualization, particle image velocimetry and hot-wire measurements. The flow is classified as three regimes: single street (the cylinder center-to-center spacing T/d 2.0). Special attention is given to the regime of 1.2 2.0, the flow structure change from the anti-phase to in-phase mode starts with a phase shift between gap vortices. The dynamical role of gap bleeding between cylinders for L/d < 1.2 is also examined

Use of Directional Spectra for Detection of Engine Cylinder Power Fault

Directory of Open Access Journals (Sweden)

Chong-Won Lee

1997-01-01

Full Text Available A diagnostic method, which uses the two-sided directional power spectra of complex-valued engine vibration signals, is presented and tested with four-cylinder compression and spark ignition engines for the diagnosis of cylinder power faults. As spectral estimators, the maximum likelihood and FFT methods are compared, and the multi-layer neural network is employed for pattern recognition. Experimental results show that the success rate for identifying the misfired cylinder is much higher with the use of two-sided directional power spectra than conventional one-sided power spectra.

Application of Potential Theory to Steady Flow Past Two Cylinders in Tandem Arrangement

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Yangyang Gao

2014-01-01

Full Text Available The wake flow patterns associated with flow past a cylinder and a cylinder-pair in tandem configuration are revisited, compared, and evaluated with respect to the streamline patterns generated based on potential flow theory and superposition of various potential flow elements. The wakes, which are vortex shedding in the lee of the cylinder(s, are reproduced by placing pairs of equal but opposite circulation elements in the potential flow field. The strength of the circulation elements determines the size of the vortices produced. The streamline patterns of flow past a pair of unequal cylinders in tandem configuration provide an indirect means to establish the threshold condition for the wake transition from that of a single bluff body to alternating reattachment behavior. This threshold condition is found to be a function of the diameter ratio, d/D (diameters d and D, d≤D , spacing ratio, L/D (centre-to-centre distance, L, to cylinder diameter, D, and equivalent incident flow speed, U. A unique functional relationship f (L/D, d/D, U of this threshold condition is established.

A guideline for fire prevention during the storage of biomass; Leitfaden zur Brandvermeidung bei der Lagerung von Biomasse

Energy Technology Data Exchange (ETDEWEB)

Ferrero, Fabio; Malow, Marcus; Schmidt, Martin; Krause, Ulrich

2009-10-14

For five years, an increasing number of fires in timber-yards is observed. A multiplicity of these fires results from self inflammation of the material. Under this aspect, the contribution under consideration reports on the fundamentals of the self inflammation by biomass using wood as an example. The methodology for the avoidance of the self inflammation of biomass is based on a combination of laboratory tests and numeric simulation in order to determine the reliable waste dump geometry and storage times. In particular, the humidity content of the stored material is very important for growth and heat production of the micro organisms. If the material does not possess optimal humidity content, heat production and the probability of self inflammation are reduced. The optimal content of humidity amounts nearly 50-60 mass-%. For the determination of a safe storage of biomass, a flow chart is developed using pinewood as an example. (orig.)

Washing water treatment process for UF{sub 6} cylinder by adjusting evaporation technology in a low temperature and low pressure

Energy Technology Data Exchange (ETDEWEB)

Kim, Ki-tae; Ju, Young-jong; Cho, Nam-chan [KEPCO Nuclear Fuel Co., Daejeon (Korea, Republic of); Kim, Yun-kwan; Jin, Chang-suk [Jeontech CO., Suwon (Korea, Republic of)

2016-10-15

The liquid waste is treated in this procedure; 1) Add NaOH to the liquid waste and filter the mixture with a screen. 2) Screened residue is dried and then stored in a uranium storage. 3) liquid part is moved to a storage tank and radioactivity is measured in the liquid. 5) If the concentration of radioactivity is lower than corresponding regulation limit, the liquid moved to a reaction tank and evaporated with additional low concentration HF in 105℃. 6) Radioactivity of distillate is measured and the value is lower than regulation, it is treated with a thermal decomposition process and discharged to the atmosphere in gas state. 7) Solid waste produced in the evaporation step is managed as solid nuclear waste. The treatment procedure mentioned above has disadvantageous points, producing large amount of solid waste as well as, high energy and chemical consumption. In this study, liquid waste from a real scaled cylinder wash process is applied to evaporation system to confirm feasibility of the application of evaporation and, to reduce waste production and energy consumption. Liquid radioactive wastewater from a real scaled UF6 cylinder wash process was applied to evaporation treatment system. Radioactive concentration in gross alpha was removed 99.9% in the evaporation system. And the concentration in distillate was lower than the discharge regulation. Removal of U-235 was 99.9% in the process. And 15 other kinds of radionuclides in the raw wastewater were removed completely. Secondary waste production of the evaporation system is 15g/L.

Separation, storage, and disposal of krypton-85: status and projects

Energy Technology Data Exchange (ETDEWEB)

Laser, M.

1976-09-15

Despite the relatively small impact of ⁸⁵Kr to man the separation of fission krypton from the off-gas of fuel reprocessing plants must be taken into account. Combined with other advantages also in power reactor stations the retention of ⁸⁵Kr seems to be attractive. Cryogenic processes are favored worldwide, because the technology has been well proven during several decades in air liquefaction and separation plants. Relatively small modifications must be made to adjust these processes to fission gas separation plants. Some fundamental data however are necessary for the design of a plant. Besides cryogenic processes a liquid adsorption for reprocessing off-gases and charcoal adsorption processes for reactor off-gas are under discussion. The retained krypton can be stored under air or water cooling in usual pressurized steel cylinders. However, legal problems may arise. The steel cylinders can be stored in engineered storage facilities for an intermediate period or finally. In Europe, however, the final storage will be questionable. Therefore, the dumping of ⁸⁵Kr into the deep sea has been proposed. For this reason a revision of the London Convention is necessary, because the dumping of ⁸⁵/Kr has not been specified. The IAEA as competent authority is asked to define the conditions for dumping. Injection of krypton containing gases into porous geologic strata may also be possible, if a very small release can be guaranteed.

Oral health status and treatment needs of Gunj marketing yard laborers of Raichur City, Karnataka

Directory of Open Access Journals (Sweden)

B Vengal Rao

2017-01-01

Full Text Available Background: Oral health is a vital part of general health and is a valuable asset of every individual. The working population in India usually belong to the lower socioeconomic group. Aim: This study was conducted to assess the oral health status and treatment needs of Gunj marketing yard laborers. Materials and Methods: A descriptive study was conducted among 550 laborers of Gunj marketing yard of Raichur city. A specially designed questionnaire was used to assess the demographic variables and oral hygiene practices. Oral health status was assessed using the WHO assessment form 1997. Simplified oral hygiene index (1964 was used to assess the oral hygiene status. Results: The mean age of the study participants was 35.1 (± 8.02 years and the mean decayed teeth, missing teeth, filled teeth, and decayed, missing, filled teeth was 2.06 (± 1.49, 0.76 (± 2.53, 0.13 (± 0.39, and 2.95 (± 3.02, respectively. The prevalence of dental caries and periodontal disease was 85.7% and 93.5%, respectively. The oral hygiene status was poor in 45.9% of the study participants. Conclusion: This study demonstrates poor oral hygiene and high prevalence of periodontal diseases and dental caries as well as a large proportion of unmet dental needs among these laborers.

Modelling and numerical simulation of vortex induced vibrations of single cylinder or cylinder arrays

International Nuclear Information System (INIS)

Jus, Y.

2011-01-01

This research thesis fits into the frame of researches achieved in the nuclear field in order to optimize the predictive abilities of sizing models of nuclear plant components. It more precisely addresses the modelling of the action exerted by the flowing fluid and the induced feedback by the structure dynamics. The objective is herein to investigate the interaction between the turbulence at the wall vicinity and the effects of non-conservative and potentially destabilizing unsteady coupling. The peculiar case of a single cylinder in infinite environment, and submitted to a transverse flow, is studied statically and then dynamically. The influence of flow regimes on dynamic response is characterized, and the quantification of fluid-structure interaction energy is assessed. The author then addresses the case of an array of cylinders, and highlights the contribution of three-dimensional macro-simulations for the analysis of flow-induced structure vibrations in subcritical regime within a High Performance Calculation (HPC) framework, and the interest of a CFD/CSM (computational fluid dynamics/computational structure mechanics) coupling in the case of turbulent flows in an industrial environment

An Unattended Verification Station for UF6 Cylinders: Development Status

International Nuclear Information System (INIS)

Smith, E.; McDonald, B.; Miller, K.; Garner, J.; March-Leuba, J.; Poland, R.

2015-01-01

In recent years, the International Atomic Energy Agency (IAEA) has pursued innovative techniques and an integrated suite of safeguards measures to address the verification challenges posed by advanced centrifuge technologies and the growth in separative work unit capacity at modern centrifuge enrichment plants. These measures would include permanently installed, unattended instruments capable of performing the routine and repetitive measurements previously performed by inspectors. Among the unattended instruments currently being explored by the IAEA is an Unattended Cylinder Verification Stations (UCVS) that could provide independent verification of the declared relative enrichment, U-235 mass and total uranium mass of all declared cylinders moving through the plant, as well as the application and verification of a ''Non-destructive Assay Fingerprint'' to preserve verification knowledge on the contents of each cylinder throughout its life in the facility. As IAEA's vision for a UCVS has evolved, Pacific Northwest National Laboratory (PNNL) and Los Alamos National Laboratory have been developing and testing candidate non-destructive assay (NDA) methods for inclusion in a UCVS. Modeling and multiple field campaigns have indicated that these methods are capable of assaying relative cylinder enrichment with a precision comparable to or substantially better than today's high-resolution handheld devices, without the need for manual wall-thickness corrections. In addition, the methods interrogate the full volume of the cylinder, thereby offering the IAEA a new capability to assay the absolute U-235 mass in the cylinder, and much-improved sensitivity to substituted or removed material. Building on this prior work, and under the auspices of the United States Support Programme to the IAEA, a UCVS field prototype is being developed and tested. This paper provides an overview of: a) hardware and software design of the prototypes, b) preparation

TR-PIV measurement of the wake behind a grooved cylinder at low Reynolds number

Science.gov (United States)

Liu, Ying Zheng; Shi, Liu Liu; Yu, Jun

2011-04-01

A comparative study of the wakes behind cylinders with grooved and smooth surfaces was performed with a view to understand the wake characteristics associated with the adult Saguaro cacti. A low-speed recirculation water channel was established for the experiment; the Reynolds number, based on the free-stream velocity and cylinder diameter (D), was kept at ReD=1500. State-of-the-art time-resolved particle image velocimetry (TR-PIV) was employed to measure a total of 20 480 realizations of the wake field at a frame rate of 250 Hz, enabling a comprehensive view of the time- and phase-averaged wake pattern. In comparison to the wake behind the smooth cylinder, the length of the recirculation zone behind the grooved cylinder was extended by nearly 18.2%, yet the longitudinal velocity fluctuation intensity was considerably weakened. A global view of the peaked spectrum of the longitudinal velocity component revealed that the intermediate region for the grooved cylinder, which approximately corresponds to the transition region where the shear layer vortices interact, merge and shed before the formation of the Karman-like vortex street, was much wider than that for the smooth one. The unsteady events near St=0.3-0.4 were detected in the intermediate region behind the grooved cylinder, but no such events were found in the smooth cylinder system. Although the formation of the Karman-like vortex street was delayed by about 0.6D downstream for the grooved cylinder, no prominent difference in the vortex street region was found in the far wake for both cylinders. The Proper Orthogonal Decomposition (POD) method was used extensively to decompose the vector and swirling strength fields, which gave a close-up view of the vortices in the near wake. The first two POD modes of the swirling strength clarified the spatio-temporal characteristics of the shear layer vortices behind the grooved cylinder. The small-scale vortices superimposed on the shear layers behind the grooved cylinder

Directed Assembly of Janus Cylinders by Controlling the Solvent Polarity.

Science.gov (United States)

Kim, Jongmin; Choi, Chang-Hyung; Yeom, Su-Jin; Eom, Naye; Kang, Kyoung-Ku; Lee, Chang-Soo

2017-08-01

This study demonstrates the possibility of controlling the directed self-assembly of microsized Janus cylinders by changing the solvent polarity of the assembly media. Experimental results are analyzed and theoretical calculations of the free energy of adhesion (ΔG ad ) are performed to elucidate the underlying basic principles and investigate the effects of the solvent on the self-assembled structures. This approach will pave a predictive route for controlling the structures of assembly depending on the solvent polarity. In particular, we find that a binary solvent system with precisely controlled polarity induces directional assembly of the microsized Janus cylinders. Thus, the formation of two-dimensional (2D) and three-dimensional (3D) assembled clusters can be reliably tuned by controlling the numbers of constituent Janus cylinders in a binary solvent system. Finally, this approach is expanded to stepwise assembly, which forms unique microstructures via secondary growth of primary seed clusters formed by the Janus cylinders. We envision that this investigation is highly promising for the construction of desired superstructures using a wide variety of polymeric Janus microparticles with chemical and physical multicompartments.

Mathematical Modeling of Partial-Porous Circular Cylinders with Water Waves

Directory of Open Access Journals (Sweden)

Min-Su Park

2015-01-01

Full Text Available The interaction of water waves with partially porous-surfaced circular cylinders was investigated. A three-dimensional numerical modeling was developed based on the complete mathematical formulation of the eigenfunction expansion method in the potential flow. Darcy’s law was applied to describe the porous boundary. The partial-porous cylinder is composed of a porous-surfaced body near the free surface, and an impermeable-surfaced body with an end-capped rigid bottom below the porous region. The optimal ratio of the porous portion to the impermeable portion can be adopted to design an effective ocean structure with minimal hydrodynamic impact. To scrutinize the hydrodynamic interactions in N partial-porous circular cylinders, the computational fluid domain is divided into three regions: an exterior region, N inner porous body regions, and N regions beneath the body. Wave excitation forces and wave run-up on multibodied partial-porous cylinders are calculated and compared for various porous-portion ratios and wave conditions, all of which significantly influence the hydrodynamic property.

Absolute measurement of the viscosity of classical and quantum fluids by rotating-cylinder viscometers

International Nuclear Information System (INIS)

Donnelly, R.J.; LaMar, M.M.

1987-01-01

We discuss the use of rotating-cylinder viscometers to determine absolute shear viscosities of classical fluids and of helium II in the context of past and current knowledge of the stability and flow of these fluids between concentric cylinders. We identify a problem in measuring the absolute viscosity when the inner cylinder is rotating and the outer cylinder is at rest. We conclude by discussing the design of viscometers for absolute viscosity measurements in helium I and helium II

Stress distribution and pressure-bearing capacity of a high-pressure split-cylinder die with prism cavity

Science.gov (United States)

Zhao, Liang; Li, Mingzhe; Wang, Liyan; Qu, Erhu; Yi, Zhuo

2018-03-01

A novel high-pressure belt-type die with a split-type cylinder is investigated with respect to extending its lifetime and improving its pressure bearing capacity. Specifically, a tungsten carbide cylinder is split into several parts along the radial direction with a prism-type cavity. In this paper, the cylinders with different split numbers are chosen to study the stress distribution and compare them with the traditional belt-type die. The simulation results indicate that the split cylinder has much smaller stress than those in the belt-type cylinder, and the statistical analysis reveals that the split-pressure cylinder is able to bear higher pressure. Experimental tests also show that the high-pressure die with a split cylinder and prism cavity has a stronger pressure-bearing capacity than a belt-type die. The split cylinder has advantages of easy manufacturing, high pressure bearing capacity, and replaceable performance.

Effect of intake swirl on the performance of single cylinder direct injection diesel engine

Science.gov (United States)

Sharma, Vinod Kumar; Mohan, Man; Mouli, Chandra

2017-11-01

In the present work, the effect of inlet manifold geometry and swirl intensity on the direct injection (DI) diesel engine performance was investigated experimentally. Modifications in inlet manifold geometry have been suggested to achieve optimized swirl for the better mixing of fuel with air. The intake swirl intensities of modified cylinder head were measured in swirl test rig at different valve lifts. Later, the overall performance of 435 CC DI diesel engine was measured using modified cylinder head. In addition, the performance of engine was compared for both modified and old cylinder head. For same operating conditions, the brake power and brake specific fuel consumption was improved by 6% and 7% respectively with modified cylinder head compared to old cylinder head. The maximum brake power of 9 HP was achieved for modified cylinder head. The results revealed that the intake swirl has great influence on engine performance.

Effect of corner radius in stabilizing the low-Re flow past a cylinder

KAUST Repository

Zhang, Wei

2017-08-03

We perform global linear stability analysis on low-Re flow past an isolated cylinder with rounded corners. The objective of the present work is to investigate the effect of the cylinder geometry (corner radius) on the stability characteristics of the flow. Our investigation sheds light on new physics that the flow can be stabilized by partially rounding the cylinder in the critical and weakly super-critical flow regimes. The flow is first stabilized and then gradually destabilized as the cylinder varies from square to circular geometry. The sensitivity analysis reveals that the variation of stability is attributed to the different spatial variation trends of the backflow velocity in the near- and far-wake regions for various cylinder geometries. The results from the stability analysis are also verified with those of the direct simulations and very good agreement is achieved.

Effect of corner radius in stabilizing the low-Re flow past a cylinder

KAUST Repository

Zhang, Wei; Samtaney, Ravindra

2017-01-01

We perform global linear stability analysis on low-Re flow past an isolated cylinder with rounded corners. The objective of the present work is to investigate the effect of the cylinder geometry (corner radius) on the stability characteristics of the flow. Our investigation sheds light on new physics that the flow can be stabilized by partially rounding the cylinder in the critical and weakly super-critical flow regimes. The flow is first stabilized and then gradually destabilized as the cylinder varies from square to circular geometry. The sensitivity analysis reveals that the variation of stability is attributed to the different spatial variation trends of the backflow velocity in the near- and far-wake regions for various cylinder geometries. The results from the stability analysis are also verified with those of the direct simulations and very good agreement is achieved.

Rotational friction coefficient of a permeable cylinder in a viscous fluid

NARCIS (Netherlands)

Wiegel, F.W.

1979-01-01

An exact expression is derived for the rotational friction coefficient of a cylinder of infinite length and constant permeability immersed in an incompressible viscous fluid. An asymptotic expression for the translational friction coefficient of a permeable cylinder moving in a sheet of viscous

Testing of the Model 48-14 overpack for UF6 cylinders

International Nuclear Information System (INIS)

Stitt, D.H.

1983-01-01

Shipment of UF 6 enriched to 1.0% or greater assay 235 U currently is done in either the 30-B overpack or the Paducah tiger overpack. The former contains a 2-1/2 ton cylinder, 30 in. in diameter, while the latter contains a 10-ton cylinder, 48 in. in diameter. There are apparent economy and safety considerations associated with shipping in the larger containers due to the reduced number of shipments and connect and disconnect operations. Further reductions in connect and disconnect operations and shipping costs could be achieved through use of the 14-ton cylinder for shipment of enriched material. With this thought, a program was initiated in 1980 to develop a protective overpack for the Model 48Y cylinder. Two prototype overpacks of wood and stainless steel construction were fabricated. The results from the drop tests and the thermal exposure test are presented

Water Entry and Exit of Horizontal Cylinder in Free Surface Flow

International Nuclear Information System (INIS)

Hafsia, Zouhaier; Maalel, Khlifa; Mnasri, Chokri; Mohamed, Omri

2009-01-01

This paper describes two-dimensional numerical simulations of the water entry and exit of horizontal circular cylinder at constant velocity. The deformation of free surface is described by Navier-Stokes (N S) equations of incompressible and viscous fluid with additional transport equation of the volume-of-fluid (VOF). The motion of the cylinder is modeled by the associated momentum source term implemented in the Phoenicis (Parabolic Hyperbolic Or Elliptic Numerical Integration Code Series) code. The domain is discretized by a fixed Cartesian grid using a finite volume method and the cylinder is represented and cut cell method. The simulated results are compared with the numerical results of Lin (2007). This comparison shows good agreement in terms of free surface evolution for water exit and sinking. However, for water entry, the jet flow simulated by Lin is not reproduced. The free surface deformation around the cylinder in downward direction is accurately predicted

Development of solid materials for UF₆ sampling: FY16 Annual Report

Energy Technology Data Exchange (ETDEWEB)

Smith, Nicholas [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Savina, Joseph [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Hebden, Andrew [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

2016-10-31

A handheld implementation of the ABACC-developed Cristallini method, which captures uranium hexafluoride samples as an inert salt, was organized in FY17 and succeeded in demonstrating the handheld sampler concept with reactive hexafluoride gases. The Cristallini method relies on the use of a hydrated substrate to react the incoming hexafluoride resulting in the formation of a stable uranyl fluoride salt. The Cristallini method has been demonstrated as a facility modification installed near the sampling tap of a gas centrifuge enrichment plant. While very successful in reducing the hazards of uranium hexafluoride sample, the method still takes a considerable amount of time and can only be used in facilities where the apparatus has been installed; this arrangement generally prohibits the sampling of filled cylinders that have already exited the facility and have been deposited in the on-site tank storage yard. The handheld unit under development will allow the use of the Cristallini method at facilities that have not been converted as well as tanks in the storage yard. The handheld system utilizes an active vacuum system, rather than a passive vacuum system in the facility setup, to drive the uranium hexafluoride onto the adsorbing media. The handheld unit will be battery operated for fully autonomous operation and will include onboard pressure sensing and flushing capability. To date, the system concept of operations was demonstrated with tungsten hexafluoride that showed the active vacuum pump with multiple cartridges of adsorbing media was viable. Concurrently, the hardened prototype system was developed and tested; removable sample cartridges were developed (the only non-COTS component to date); and preparations were made for uranium tests and a domestic field test.

Evaluation of Flow Accelerated Corrosion of Carbon Steel with Rotating Cylinder

International Nuclear Information System (INIS)

Park, Tae Jun; Lee, Eun Hee; Kim, Kyung Mo; Kim, Hong Pyo

2012-01-01

Flow accelerated corrosion (FAC) of the carbon steel piping in nuclear power plants (NPPs) has been major issue in nuclear industry. Rotating cylinder FAC test facility was designed and fabricated and then performance of the facility was evaluated. The facility is very simple in design and economic in fabrication and can be used in material and chemistry screening test. The facility is equipped with on line monitoring of pH, conductivity, dissolved oxygen(DO), and temperature. Fluid velocity is controlled with rotating speed of the cylinder with a test specimen. FAC test of SA106 Gr. B carbon steel under 4 m/s flow velocity was performed with the rotating cylinder at DO concentration of less than 1 ppb and of 1.3 ppm. Also a corrosion test of the carbon steel at static condition, that is at zero fluid velocity, of test specimen and solution was performed at pH from 8 to 10 for comparison with the FAC data. For corrosion test in static condition, the amount of non adherent corrosion product was almost constant at pH ranging from 8 to 10. But adherent corrosion product decreased with increasing pH. This trend is consistent with decrease of Fe solubility with an increase in pH. For FAC test with rotating cylinder FAC test facility, the amount of non adherent corrosion product was also almost same for both DO concentrations. The rotating cylinder FAC test facility will be further improved by redesigning rotating cylinder and FAC specimen geometry for future work

Extended Analytic Linear Model of Hydraulic Cylinder With Respect Different Piston Areas and Volumes

OpenAIRE

Petr KOŇAŘÍK

2009-01-01

Standard analytic linear model of hydraulic cylinder usually comes from assumptions of identical action piston areas on both sides of hydraulic cylinder (double piston rod) and suitable operation point, which is usually chosen in the middle of piston. By reason of that volumes inside of cylinder are than same. Moreover for control of that arrangement of hydraulic cylinder, usually controlled by 4/3 servovalve, the same mount of flows comes in and comes out to each of chambers of hydraulic cyl...

Flow structure from a horizontal cylinder coincident with a free surface in shallow water flow

Directory of Open Access Journals (Sweden)

Kahraman Ali

2012-01-01

Full Text Available Vortex formation from a horizontal cylinder coincident with a free surface of a shallow water flow having a depth of 25.4 [mm] was experimentally investigated using the PIV technique. Instantaneous and time-averaged flow patterns in the wake region of the cylinder were examined for three different cylinder diameter values under the fully developed turbulent boundary layer condition. Reynolds numbers were in the range of 1124£ Re£ 3374 and Froude numbers were in the range of 0.41 £ Fr £ 0.71 based on the cylinder diameter. It was found that a jet-like flow giving rise to increasing the flow entrainment between the core and wake regions depending on the cylinder diameter was formed between the lower surface of the cylinder and bottom surface of the channel. Vorticity intensity, Reynolds stress correlations and the primary recirculating bubble lengths were grown to higher values with increasing the cylinder diameter. On the other hand, in the case of the lowest level of the jet-like flow emanating from the beneath of the smallest cylinder, the variation of flow characteristics were attenuated significantly in a shorter distance. The variation of the reattachment location of the separated flow to the free-surface is a strong function of the cylinder diameter and the Froude number.

A novel approach to estimating potential maximum heavy metal exposure to ship recycling yard workers in Alang, India

Energy Technology Data Exchange (ETDEWEB)

Deshpande, Paritosh C.; Tilwankar, Atit K.; Asolekar, Shyam R., E-mail: asolekar@iitb.ac.in

2012-11-01

The 180 ship recycling yards located on Alang-Sosiya beach in the State of Gujarat on the west coast of India is the world's largest cluster engaged in dismantling. Yearly 350 ships have been dismantled (avg. 10,000 ton steel/ship) with the involvement of about 60,000 workers. Cutting and scrapping of plates or scraping of painted metal surfaces happens to be the commonly performed operation during ship breaking. The pollutants released from a typical plate-cutting operation can potentially either affect workers directly by contaminating the breathing zone (air pollution) or can potentially add pollution load into the intertidal zone and contaminate sediments when pollutants get emitted in the secondary working zone and gets subjected to tidal forces. There was a two-pronged purpose behind the mathematical modeling exercise performed in this study. First, to estimate the zone of influence up to which the effect of plume would extend. Second, to estimate the cumulative maximum concentration of heavy metals that can potentially occur in ambient atmosphere of a given yard. The cumulative maximum heavy metal concentration was predicted by the model to be between 113 {mu}g/Nm{sup 3} and 428 {mu}g/Nm{sup 3} (at 4 m/s and 1 m/s near-ground wind speeds, respectively). For example, centerline concentrations of lead (Pb) in the yard could be placed between 8 and 30 {mu}g/Nm{sup 3}. These estimates are much higher than the Indian National Ambient Air Quality Standards (NAAQS) for Pb (0.5 {mu}g/Nm{sup 3}). This research has already become the critical science and technology inputs for formulation of policies for eco-friendly dismantling of ships, formulation of ideal procedure and corresponding health, safety, and environment provisions. The insights obtained from this research are also being used in developing appropriate technologies for minimizing exposure to workers and minimizing possibilities of causing heavy metal pollution in the intertidal zone of ship recycling

Induced charge electrophoresis of a conducting cylinder in a nonconducting cylindrical pore and its micromotoring application

Science.gov (United States)

Feng, Huicheng; Wong, Teck Neng; Che, Zhizhao

2016-08-01

Induced charge electrophoresis of a conducting cylinder suspended in a nonconducting cylindrical pore is theoretically analyzed and a micromotor is proposed that utilizes the cylinder rotation. The cylinder velocities are analytically obtained in the Dirichlet and the Neumann boundary conditions of the electric field on the cylindrical pore. The results show that the cylinder not only translates but also rotates when it is eccentric with respect to the cylindrical pore. The influences of a number of parameters on the cylinder velocities are characterized in detail. The cylinder trajectories show that the cylinder approaches and becomes stationary at certain positions within the cylindrical pore. The proposed micromotor is capable of working under a heavy load with a high rotational velocity when the eccentricity is large and the applied electric field is strong.

Integrated Treatment and Storage Solutions for Solid Radioactive Waste at the Russian Shipyard Near Polyarny

International Nuclear Information System (INIS)

Griffith, A.; Engoy, T.; Endregard, M.; Busmundrud, O.; Schwab, P.; Nazarian, A.; Krumrine, P.; Backe, S.; Gorin, S.; Evans, B.

2002-01-01

Russian Navy Yard No. 10 (Shkval), near the city of Murmansk, has been designated as the recipient for Solid Radioactive Waste (SRW) pretreatment and storage facilities under the Arctic Military Environmental Cooperation (AMEC) Program. This shipyard serves the Northern Fleet by servicing, repairing, and dismantling naval vessels. Specifically, seven nuclear submarines of the first and second generation and Victor class are laid up at this shipyard, awaiting defueling and dismantlement. One first generation nuclear submarine has already been dismantled there, but recently progress on dismantlement has slowed because all the available storage space is full. SRW has been placed in metal storage containers, which have been moved outside of the actual storage site, which increases the environmental risks. AMEC is a cooperative effort between the Russian Federation, Kingdom of Norway and the United States. AMEC Projects 1.3 and 1.4 specifically address waste treatment and storage issues. Various waste treatment options have been assessed, technologies selected, and now integrated facilities are being designed and constructed to address these problems. Treatment technologies that are being designed and constructed include a mobile pretreatment facility comprising waste assay, segregation, size reduction, compaction and repackaging operations. Waste storage technologies include metal and concrete containers, and lightweight modular storage buildings. This paper focuses on the problems and challenges that are and will be faced at the Polyarninsky Shipyard. Specifically, discussion of the waste quantities, types, and conditions and various site considerations versus the various technologies that are to be employed will be provided. A systems approach at the site is being proposed by the Russian partners, therefore integration with other ongoing and planned operations at the site will also be discussed

Cylinder with differential piston for mass measurements

Energy Technology Data Exchange (ETDEWEB)

Bordeaşu, I.; Bălăşoiu, V. [Universitatea Politehnica din Timişoara, Timosoara (Romania); Hadă, A. [UniversitateaPolitehnicaBucureşti, Bucureşti (Romania); Popoviciu, M. [Academy of Romanian ScientistsTimişoara Branch (Romania)

2007-07-01

The paper presents a cylinder with differential piston, adapted for measuring the weight of fixed objects such as: fuel tanks (regardless of their capacity), bunkers and silos for all kind of materials, or mobile objects such as: automobiles, trucks, locomotives and railway cars. Although, the cylinder with differential piston is used on a large scale in hydraulic drive or hydraulic control circuits, till now it was not used as constituent part for weight measurements devices. The novelty of the present paper is precisely the use of the device for such purposes. Based on a computation algorithm, the paper presents the general design (assembly), of the device used for weighing important masses (1…. 100 tones). The fundamental idea consist in the fact that, a mass over 10 tones may be weighted with a helicoidally spring subjected to an axial force between 0 and 3000 N, with a deflection of about 30 mm. Simultaneously with the mechanical part, the electronic recording system is also described. The great advantage of the presented device consist in the fact that it can be used in heavy polluted atmosphere or difficult topographic conditions as a result of both the small dimensions and the protection systems adopted. Keywords: cylinder hydraulic with differential piston, hydrostatic pressure, measuring devices.

Experimental Study of 3D Movement in Cushioning of Hydraulic Cylinder

Directory of Open Access Journals (Sweden)

Antonio Algar

2017-05-01

Full Text Available A double acting cylinder operation has been fully monitored in its key functional parameters, focused on characterization of end-of-stroke cushioning and starting phases. Being the cylinder performance reliant in the piston constructive geometry, the number and location of piston circumferential grooves is a significant parameter affecting the internal cushioning system performance. An eddy current displacement sensor assembled in the piston allows assessment of piston radial displacement inside the cylinder tube, which is directly related with the studied operating phases. Due to such 3D displacements, the piston becomes as an active and self-adjusting element along the functional cycle of the cylinder. Mechanical joints orientation and operating pressure are also relevant parameters affecting piston radial displacement and, thus, the cushioning and starting performance. Computational Fluid Dynamics (CFD results confirm the observed functional role of the perimeter grooves; the flow and pressure distributions, where develops a significant radial force, are also in accordance with the registered radial displacement.

Simulating thermal behavior of AECL's spent fuel dry storage system with CATHENA

Energy Technology Data Exchange (ETDEWEB)

Sabourin, G. [Atomic Energy of Canada Limited, Montreal, PQ (Canada)

1998-07-01

This paper documents the comparisons between CATHENA predictions and temperature measurements taken at the Gentilly-2 NPP spent fuel dry storage facility and in a mock--up of a storage basket placed inside a storage cylinder. It also presents CATHENA temperature predictions related to the storage of spent fuel in MACSTOR modules as planned for Ignalina NPP, Lithuania. CATHENA has been chosen because it can simulate many noncondensable gases including air and helium, and because of its great flexibility in the representation of the MACSTOR module geometry. The results of the simulations show good agreement with the experimental measurements. The two comparisons indicate that CATHENA can be used to simulate heat transfer from the fuel to the external air circuit of the spent fuel dry storage system. For the Ignalina MACSTOR module, containing RBMK fuel having higher heat release than typical CANDU fuel, CATHENA predicts that the maximum fuel temperature is expected to be around 240 deg C, giving an acceptable margin below the maximum allowed temperature of 300 deg C. In conclusion, this paper shows that the thermalhydraulic code CATHENA can accurately predict the thermal behavior AECL's air cooled spent fuel dry storage system. (author)

Magnus effect on laminar flow around a rotating cylinder

International Nuclear Information System (INIS)

Amarante, J.C.A.

1989-01-01

The laminar flow around a rotating cylinder is studied, through the numerical solution of the full Navier-Stokes equations, for Reynolds number, based on cylinder radius, varying between 0.5 and 25 and for non-dimensional tangential velocities of the body surface between zero and 8. The Taylor and Hughes method is employed in the theoretical investigation. The Magnus lift coefficient and the drag coefficient are obtained and the presure and vorticity distribution are calculated. (author)

Cylinders out of a top hat: counts-in-cells for projected densities

Science.gov (United States)

Uhlemann, Cora; Pichon, Christophe; Codis, Sandrine; L'Huillier, Benjamin; Kim, Juhan; Bernardeau, Francis; Park, Changbom; Prunet, Simon

2018-06-01

Large deviation statistics is implemented to predict the statistics of cosmic densities in cylinders applicable to photometric surveys. It yields few per cent accurate analytical predictions for the one-point probability distribution function (PDF) of densities in concentric or compensated cylinders; and also captures the density dependence of their angular clustering (cylinder bias). All predictions are found to be in excellent agreement with the cosmological simulation Horizon Run 4 in the quasi-linear regime where standard perturbation theory normally breaks down. These results are combined with a simple local bias model that relates dark matter and tracer densities in cylinders and validated on simulated halo catalogues. This formalism can be used to probe cosmology with existing and upcoming photometric surveys like DES, Euclid or WFIRST containing billions of galaxies.

Localized surface plasmon modes in a system of two interacting metallic cylinders

DEFF Research Database (Denmark)

Babicheva, Viktoriia; Vergeles, Sergey S.; Vorobev, Petr E.

2012-01-01

We study an optical response of a system of two parallel close metallic cylinders having nanoscale dimensions. Surface plasmon excitation in the gap between the cylinders are specifically analyzed. In particular, resonance frequencies and field enhancement were investigated as functions of geomet......We study an optical response of a system of two parallel close metallic cylinders having nanoscale dimensions. Surface plasmon excitation in the gap between the cylinders are specifically analyzed. In particular, resonance frequencies and field enhancement were investigated as functions...... of geometrical characteristics of the system and Ohmic losses in the metal. The results of numerical simulations were systematically compared with the analytical theory, obtained in the quasi-static limit. The analytical method was generalized in order to take into account the retardation effects. We also...

Analysis of residual stresses in a long hollow cylinder

International Nuclear Information System (INIS)

Tokovyy, Yuriy V.; Ma, Chien-Ching

2011-01-01

This paper presents an analytical method for solving the axisymmetric stress problem for a long hollow cylinder subjected to locally-distributed residual (incompatible) strains. This method is based on direct integration of the equilibrium and compatibility equations, which thereby have been reduced to the set of two governing equations for two key functions with corresponding boundary and integral conditions. The governing equations were solved by making use of the Fourier integral transformation. Application of the method is illustrated with an analysis of the welding residual stresses in a butt-welded thick-walled pipe. - Highlights: → A solution to the axisymmetric stress problem for a hollow cylinder is constructed. → The cylinder is subjected to a field of locally-distributed residual strains. → The method is based on direct integration of the equilibrium equations. → An application of our solution to analysis of welding residual stresses is considered.

Criticality safety review of 2 1/2-, 10-, and 14-ton UF6 cylinders

International Nuclear Information System (INIS)

Broadhead, B.L.

1991-10-01

Currently, UF 6 cylinders designed to contain 2 1/2 tons of UF 6 are classified as Fissile Class 2 packages with a transport index (TI) of 5 for the purpose of transportation. The 10-ton UF 6 cylinders are classified as Fissile Class 1 with no TI assigned for transportation. The 14-ton cylinders, although not certified for transport with enrichments greater than 1 wt % because they have no approved overpack, can be used in on-site operations for enrichments greater than 1 wt %. The maximum 235 U enrichments for these cylinders are 5.0 wt % for the 2 1/2-ton cylinder and 4.5 wt % for the 10- and 14-ton cylinders. This work reviews the suitability for reclassification of the 2 1/2-ton UF 6 packages as Fissile Class 1 with a maximum 235 U enrichment of 5 wt %. Additionally, the 10- and 14-ton cylinders are reviewed to address a change in maximum 235 U enrichment from 4.5 to 5 wt %. Based on this evaluation, the 2 1/2-ton UF 6 cylinders meet the 10 CFR.71 criteria for Fissile Class 1 packages, and no TI is needed for criticality safety purposes; however, a TI may be required based on radiation from the packages. Similarly, the 10- and 14-ton UF 6 packages appear acceptable for a maximum enrichment rating change to 5 wt % 235 U. 11 refs., 13 figs., 7 tabs

Evanescent wave scattering at off-axis incidence on multiple cylinders located near a surface

International Nuclear Information System (INIS)

Lee, Siu-Chun

2015-01-01

The scattering characteristics of an infinite cylinder are strongly influenced by the incidence angle relative to its axis. If the incident wave propagates in the plane normal to the axis of the cylinder, the polarization of the scattered wave remains unchanged and the scattered wave propagates in the same plan as the incident wave. At off-axis incidence such that the incident direction makes an oblique angle with the cylinder axis, the scattered wave is depolarized, and its spatial distribution becomes three-dimensional. This paper presents the scattering solution for oblique incidence on multiple parallel cylinders located near a planar interface by an evanescent wave that is generated by total internal reflection of the source wave propagating in the higher refractive index substrate. Hertz potentials are utilized to formulate the interaction of inhomogeneous waves with the cylinders, scattering at the substrate interface, and near field scattering between the cylinders. Analytic formulas are derived for the electromagnetic fields and Poynting vector of scattered radiation in the near-field and their asymptotic forms in the far-field. Numerical examples are shown to illustrate scattering of evanescent wave by multiple cylinders at off-axis incidence. - Highlights: • Developed an exact solution for off-axis incidence on multiple cylinders. • Included depolarization, near-field scattering, and Fresnel effect in theory. • Derived analytic formulas for scattered radiation in the far field. • Illustrated evanescent scattering at off-axis incidence by numerical data

Effect of catalytic cylinders on autothermal reforming of methane for hydrogen production in a microchamber reactor.

Science.gov (United States)

Yan, Yunfei; Guo, Hongliang; Zhang, Li; Zhu, Junchen; Yang, Zhongqing; Tang, Qiang; Ji, Xin

2014-01-01

A new multicylinder microchamber reactor is designed on autothermal reforming of methane for hydrogen production, and its performance and thermal behavior, that is, based on the reaction mechanism, is numerically investigated by varying the cylinder radius, cylinder spacing, and cylinder layout. The results show that larger cylinder radius can promote reforming reaction; the mass fraction of methane decreased from 26% to 21% with cylinder radius from 0.25 mm to 0.75 mm; compact cylinder spacing corresponds to more catalytic surface and the time to steady state is decreased from 40 s to 20 s; alteration of staggered and aligned cylinder layout at constant inlet flow rates does not result in significant difference in reactor performance and it can be neglected. The results provide an indication and optimize performance of reactor; it achieves higher conversion compared with other reforming reactors.

The ultimate disposition of depleted uranium