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1

Freewheeling hydraulic power mills  

Microsoft Academic Search

Components of free-wheeling power plants that use the hydraulic forces of winds or water currents are described. Fore and aft cones to increase throughput, multiple impellers driving a single rotor, swivel mounts to support nacelles, dc electrolytic cells for the production of H2 and O2, and cryogenic storage systems for the gases are the principle elements in the power mill

F. F. Hall

1979-01-01

2

Hydraulically refueled battery employing a packed bed metal particle electrode  

DOEpatents

A secondary zinc air cell, or another selected metal air cell, employing a spouted/packed metal particle bed and an air electrode. More specifically, two embodiments of a cell, one that is capable of being hydraulically recharged, and a second that is capable of being either hydraulically or electrically recharged. Additionally, each cell includes a sloped bottom portion to cause stirring of the electrolyte/metal particulate slurry when the cell is being hydraulically emptied and refilled during hydraulically recharging of the cell.

Siu, Stanley C. (Castro Valley, CA); Evans, James W. (Piedmont, CA)

1998-01-01

3

Hydraulically refueled battery employing a packed bed metal particle electrode  

DOEpatents

A secondary zinc air cell, or another selected metal air cell, employing a spouted/packed metal particle bed and an air electrode is described. More specifically, two embodiments of a cell, one that is capable of being hydraulically recharged, and a second that is capable of being either hydraulically or electrically recharged. Additionally, each cell includes a sloped bottom portion to cause stirring of the electrolyte/metal particulate slurry when the cell is being hydraulically emptied and refilled during hydraulically recharging of the cell. 15 figs.

Siu, S.C.; Evans, J.W.

1998-12-15

4

The furification process in hydraulic packed-bed wash columns  

Microsoft Academic Search

Hydraulic packed-bed wash columns are continuous solid-liquid separators, which can be applied as the final step in fractional suspension crystallization processes aimed at ultrapurification of organic compounds. In this paper an experimental study and a mathematical model of the purification process in packed-bed wash columns are presented. The developed model can be used to calculate concentration, temperature and porosity profiles

M. Matsuoka

1995-01-01

5

VMEbus packs multiprocessing power  

SciTech Connect

VMEbus is on the move. With support from more than 300 board vendors, the bus continues to add a formidable array of powerful products aimed at high-throughput, fast-I/O, multiprocessing and real-time industrial-control tasks. In fact, the capabilities of these integrated boards and software center on certain key areas: A slew of 32-bit-processor-based boards with clock speeds up to 25 MHz; Zero wait-state access up to 4M bytes of on-board, dual-ported RAM; Multiple high-speed intelligent I/O channels; A variety of multitasking, multiuser and real-time operating systems; Data and/or instruction caches and high-speed local buses for fast memory access; Integrated math coprocessors and memory-management chips; and Fast signal-processing boards. This article discusses some of the products that are available.

Victor, J.

1987-04-01

6

Fluid Power/Basic Hydraulics. Instructor's Guide.  

ERIC Educational Resources Information Center

|This guide is designed to assist industrial vocational instructors in teaching a course on fluid power and basic hydraulics. Covered in the unit on the basics of fluid power and hydraulics are the following topics: the fundamentals of fluid power and hydraulics, basic hydraulic circuits, and servicing a hydraulic jack. The second unit, consisting…

Stanbery, Richard

7

On hydraulic permeability of random packs of monodisperse spheres: Direct flow simulations versus correlations  

Microsoft Academic Search

Hydraulic permeability is studied in porous media consisting of randomly distributed monodisperse spheres by means of computational fluid dynamics (CFD) simulations. The packing of spheres is generated by inserting a certain number of nonoverlapping spherical particles inside a cubic box at both low and high packing fractions using proper algorithms. Fluid flow simulations are performed within the interparticulate porous space

Ehsan Zaman; Payman Jalali

2010-01-01

8

Power hydraulics - switched mode control of hydraulic actuation  

Microsoft Academic Search

This paper is concerned with the application of switching technology to hydraulic actuation. Over the last 50 years with advances in power electronics, faster and faster static switches have been developed and applied to the control of motors. Hydraulic technology evolved in the opposite direction: switching control was not considered, and more and more accurate proportional flow\\/pressure control devices (servovalves

Emanuele Guglielmino; Claudio Semini; Helmut Kogler; Rudolf Scheidl; Darwin G. Caldwell

2010-01-01

9

Wind powered hydraulic heating system  

Microsoft Academic Search

A heating apparatus is described which includes a circulation system for hydraulic fluid, a pump for pumping the fluid, a windmill for driving the pump, an adjustable pressure responsive relief valve for restricting the flow of hydraulic fluid in the circulation system and establishing therein an adjustable fluid pressure reduction, a sensor responsive to the wind velocity encountered by the

1978-01-01

10

VORTICITY IN HYDRAULIC POWER EQUIPMENT  

Microsoft Academic Search

The paper presents a numerical simulation and analysis of the flow inside a hydraulic poppet valve and hydraulic control valve. This paper summarizes the successful application of Computational Fluid Dynamics (CFD) analysis to study the effect of spool slot configuration on spool and cavitation generation inside both the poppet valve and control valve. The hidrodynamic field inside in the valve

Romeo F. SUSAN-RESIGA

11

Ocean thermal gradient hydraulic power plant.  

PubMed

Solar energy stored in the oceans may be used to generate power by exploiting ploiting thermal gradients. A proposed open-cycle system uses low-pressure steam to elevate vate water, which is then run through a hydraulic turbine to generate power. The device is analogous to an air lift pump. PMID:17813707

Beck, E J

1975-07-25

12

Autoerotic fatalities with power hydraulics.  

PubMed

We report two cases in which men used the hydraulic shovels on tractors to suspend themselves for masochistic sexual stimulation. One man developed a romantic attachment to a tractor, even giving it a name and writing poetry in its honor. He died accidentally while intentionally asphyxiating himself through suspension by the neck, leaving clues that he enjoyed perceptual distortions during asphyxiation. The other man engaged in sexual bondage and transvestic fetishism, but did not purposely asphyxiate himself. He died when accidentally pinned to the ground under a shovel after intentionally suspending himself by the ankles. We compare these cases with other autoerotic fatalities involving perceptual distortion, cross-dressing, machinery, and postural asphyxiation by chest compression. PMID:8454997

O'Halloran, R L; Dietz, P E

1993-03-01

13

Experimental Studies of Wave Hydraulic Power Units  

Microsoft Academic Search

At the Ukrgidroproekt Joint-Stock Co. (Kharkov), research and development studies concerned with the use of wave energy have been conducted over a period of years. Under a Reseacrh and Developement program in 1994 – 1995, a model of a wave power plant was tested at a laboratory for large-scale hydraulic and geotechnic studies (LHGSL, Dneprodzerzhinsk) and promising results were obtained

V. P. Drobakhin; N. D. Nolirovskaya; V. A. Osadchuk; A. V. Savchenko

2003-01-01

14

Optimal Power Management for a Hydraulic Hybrid Delivery Truck  

Microsoft Academic Search

Hydraulic hybrid propulsion and energy storage components demonstrate characteristics that are very different from their electric counterparts, thus requiring unique control strategies. This paper presents a methodology for developing a power management strategy tailored specifically to a parallel Hydraulic Hybrid Vehicle (HHV) configured for a medium-size delivery truck. The Hydraulic H ybrid Vehicle is modelled in the MATLAB\\/SIMULINK environment to

Bin Wu; Chan-Chiao Lin; Zoran Filipi; Huei Peng; Dennis Assanis

2004-01-01

15

Research on hydraulic-powered roof supports test problems  

Microsoft Academic Search

The load-bearing characters of hydraulic-powered roof support with dual telescopic legs were analyzed. With a specific type\\u000a hydraulic-powered roof support with dual telescopic legs for research object, the inside load test problems in factories was\\u000a analyzed, and the correct test methods were given, which can enhance the test efficiency and make the factories away from\\u000a the error design of hydraulic-powered

Hong-bo Sun; Jin-qiu Jiang; Qiang Ma

2011-01-01

16

Hydraulic Tidal and Wind Power System Sizing.  

National Technical Information Service (NTIS)

Tidal energy, offshore wind energy, and onshore wind energy can be converted to electricity at a central ground location by converting their respective energies into high-pressure hydraulic flows that are transmitted to a system of hydraulic generators by...

J. A. Jones

2012-01-01

17

49 CFR 173.172 - Aircraft hydraulic power unit fuel tank.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 false Aircraft hydraulic power unit fuel tank...Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... § 173.172 Aircraft hydraulic power unit fuel tank. Aircraft hydraulic power unit fuel...

2009-10-01

18

49 CFR 173.172 - Aircraft hydraulic power unit fuel tank.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Aircraft hydraulic power unit fuel tank...Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... § 173.172 Aircraft hydraulic power unit fuel tank. Aircraft hydraulic power unit fuel...

2010-10-01

19

Hydraulic characteristics in superconducting power transmission cables  

NASA Astrophysics Data System (ADS)

The hydraulic characteristics of sub-cooled nitrogen in superconducting power transmission line have been investigated to design the transmission line. To estimate the friction factor in corrugated pipes, the pressure drop was measured across a 10-m length corrugated pipe for various mass flow rates and compared with that in smooth pipes (Proc. 17th Cryo. Eng. Conf. (1998) 475). Another concern is the cooling method of the transmission line. A usual counter-flow cooling method has been found to be very difficult at liquid nitrogen temperature, because the thermal conductivity of the dielectric materials between the counter-flows at liquid nitrogen temperature are 10 times larger than that at liquid helium temperature. Instead, an externally cooling method was proposed (Proc. 17th Cryo. Eng. Conf. (1998) 475). As the results, the friction factor of outer corrugated jacket within three cables has become an important parameter to design the transmission lines. This friction factor is measured and compared with various formulas in this paper.

Fuchino, S.; Tamada, N.; Ishii, I.; Higuchi, N.

2001-05-01

20

The research of wind power optimized capacity configuration in hydraulic power system  

Microsoft Academic Search

Buerjin power grid of Xinjiang province in China is an alone hydraulic-wind power mutual compensation system, which is composed of two hydraulic generators with capacity of 2000 KW and one with 2500 KW and seven wind generators with capacity of 150 KW, the wind power capacity account for almost 13.0 percent of total power system capacity. In order to study

Feng-ting Li; Qin Chao; Xun-jiang Dai

2008-01-01

21

Pressure surges in power plant hydraulic systems  

Microsoft Academic Search

Design approaches for reducing pressure surges in circulating water systems (CWS) are discussed, and the effect of pipe material on pressure transients in long hydraulic pipelines is examined. Three ways are discussed for reducing surges in CWS: selection of optimum pump discharge valve closure time, two-speed operation for pump discharge valve closure, and seal well relocation. The effect of pipe

Samra

1978-01-01

22

Performance of a MR hydraulic power actuation system  

NASA Astrophysics Data System (ADS)

In this paper, a set of MR valves is implemented within a Wheatstone bridge hydraulic power circuit to drive a hydraulic actuator using a gear pump. A compact hydraulic power actuation system is developed that is comprised of a Wheatstone bridge network of magnetorheological (MR) valves with a conventional hydraulic cylinder. There are many advantages of using MR valves in hydraulic actuation systems, including: valves have no moving parts, eliminating the complexity and durability issues in conventional mechanical valves. In such a system MR fluid is used as the hydraulic fluid. A constant volume pump is used to pressurize the MR fluid which eliminates the effect of fluid compliance to a large degree. If a change in direction is required, the flow through each of the valves in the Wheatstone bridge can be controlled smoothly via changing the applied magnetic field. A magnetic field analysis is conducted to design a high-efficiency compact MR valve. The behavior and performance of the MR valve is expressed in terms of non-dimensional parameters. The performance of the hydraulic actuator system with Wheatstone bridge network of MR valves is derived using three different constitutive models of the MR fluid: an idealized model (infinite yield stress), a Bingham-plastic model, and a biviscous model. The analytical system efficiency in each case is compared and departures from ideal behavior, that is, a valve with infinite blocking pressure, are recognized.

Yoo, Jinhyeong; Wereley, Norman M.

2002-07-01

23

Dynamic characteristics of hydraulic power steering system with accumulator in load-haul-dump vehicle  

Microsoft Academic Search

Using hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle as a simulation example, the dynamic characteristics\\u000a of hydraulic power steering system in load-haul-dump vehicle were simulated and discussed with SIMULINK software and hydraulic\\u000a control theory. The results show that the dynamic characteristics of hydraulic power steering system are improved obviously\\u000a by using bladder accumulator, the hydraulic power steering

Zhong-jiong Yang; Qing-hua He; Bo Liu

2004-01-01

24

Hydraulics.  

ERIC Educational Resources Information Center

|This curriculum guide contains a course in hydraulics to train entry-level workers for automotive mechanics and other fields that utilize hydraulics. The module contains 14 instructional units that cover the following topics: (1) introduction to hydraulics; (2) fundamentals of hydraulics; (3) reservoirs; (4) lines, fittings, and couplers; (5)…

Decker, Robert L.; Kirby, Klane

25

Rotor packing of an atomic-power-station centrifugal cooling pump  

Microsoft Academic Search

Centrifugal cooling pumps have to be highly reliable because of the complex conditions under which they operate in atomic power stations. Fabrication of reliable shaft packings is therefore a major task. Of the known mechanical, hydrostatic and other types of face packings, the requirements are best met by the face packing with a self-adjusted gap. The working parameters and the

N. V. Penedrii; B. N. Perminov

1983-01-01

26

Distillation columns containing structured packings: A comprehensive model for their performance. 1. Hydraulic models  

Microsoft Academic Search

A mechanistically-based model has been developed to aid the analysis and design of distillation columns containing structured packings of the corrugated plate type. The model encompasses the important, and related, parameters of liquid holdup, pressure drop, flooding, and mass-transfer efficiency. Since it deals with the countercurrent contacting of liquid with gas or vapor, the model may also be applied to

J. Antonio Rocha; Jose L. Bravo; James R. Fair

1993-01-01

27

Modeling and simulation of hydraulic power steering system  

Microsoft Academic Search

This paper targeted by a car, its hydraulic power steering (HPS) system was modeled in AMESIM, which is a one- dimensional system simulation software. And its vehicle model was established in Virtual.Lab Motion which is a three- dimensional multi-body dynamics simulation software. Then, couple simulation would carry out between AMESIM and Motion. When the car was in low speed and

Zhigang Fang; Xuexun Guo; Guanneng Xu

2011-01-01

28

High Speed Hydraulic Starter Motor for Aircraft Auxiliary Power Unit.  

National Technical Information Service (NTIS)

The purpose of this research program was to develop a vane type hydraulic starter motor for aircraft, high-speed, auxiliary power units. The goals were to achieve a starter cutoff speed of 50,000 RPM and an inlet pressure capability of 8000 PSIG maximum u...

H. T. Johnson N. F. Pedersen

1976-01-01

29

Hydraulics.  

ERIC Educational Resources Information Center

|These instructional materials provide an orientation to hydraulics for use at the postsecondary level. The first of 12 sections presents an introduction to hydraulics, including discussion of principles of liquids, definitions, liquid flow, the two types of hydraulic fluids, pressure gauges, and strainers and filters. The second section…

Engelbrecht, Nancy; And Others

30

Effect of the coupling between hydraulic turbine set and power grid on power grid dynamic stability  

Microsoft Academic Search

With the proportion of hydroelectric power station in power grid and the single-turbine capacity larger and larger, the effect of hydraulic turbine set on power system dynamic stability will be more significant. The power oscillation phenomenon, which affects the safe and stable operation of power system, occurred many times in China. For example, on October 29th, 2005, low frequency oscillation

Xin Jianbo; Han Zhiyong; He Renmu

2009-01-01

31

Development of hybrid hydraulic-electric power units for field and service robots  

Microsoft Academic Search

Abstract—Energetic autonomy,of a hydraulic-based mobile robot requires a power,source capable of both hydraulic and electrical power generation. The hydraulic power is used for locomotion, and the electric power is used for the control computer, sensors and other peripherals. In addition, the power,source must be lightweight and quiet. This study presents several designs of internal combustion engine-based power units. Each power

Kurt Amundson; Justin Raade; Nathan Harding; Hami Kazerooni

2006-01-01

32

Hydraulic landscapes and imperial power in the Near East  

Microsoft Academic Search

Over the past 20 years archaeological surveys and remote sensing have contributed significantly to the discovery of ancient\\u000a hydraulic systems in the Middle East. The significance of this increase, namely in the scale and number of canals, conduits\\u000a and qanats, is examined and related to the role of power and the administration of the later territorial empires which date\\u000a from the

Tony James Wilkinson; Louise Rayne

2010-01-01

33

Powered orthosis and attachable power-assist device with Hydraulic Bilateral Servo System.  

PubMed

This paper discusses the developments and control strategies of exoskeleton-type robot systems for the application of an upper limb powered orthosis and an attachable power-assist device for care-givers. Hydraulic Bilateral Servo System, which consist of a computer controlled motor, parallel connected hydraulic actuators, position sensors, and pressure sensors, are installed in the system to derive the joint motion of the exoskeleton arm. The types of hydraulic component structure and the control strategy are discussed in relation to the design philosophy and target joints motions. PMID:24110321

Ohnishi, Kengo; Saito, Yukio; Oshima, Toru; Higashihara, Takanori

2013-07-01

34

Hydraulics.  

ERIC Educational Resources Information Center

|Designed for use in courses where students are expected to become proficient in the area of hydraulics, including diesel engine mechanic programs, this curriculum guide is comprised of fourteen units of instruction. Unit titles include (1) Introduction, (2) Fundamentals of Hydraulics, (3) Reservoirs, (4) Lines, Fittings, and Couplers, (5) Seals,…

Decker, Robert L.

35

A Methodology for Selecting High Thermal-Hydraulic Performance Fuel Configurations for Tightly Packed Epithermal Core Designs  

SciTech Connect

Cylindrical fuel pins with wires are the design of choice for tightly packed fuel arrays. However, it is important to investigate novel fuel configurations in order to increase the thermal margins. Hence, new fuel designs have been studied for the epithermal option of the light water-cooled IRIS core. These designs are also of potential use in other tightly packed, epithermal advanced core designs.First, design equations have been used to determine number, height, and size of the principal features (clad, gap, fuel cross-sectional area) of the novel fuel configurations under investigation. Then, performance indices have been introduced to relate fuel geometrical characteristics to selected thermal-hydraulic parameters, such as pressure drop, critical heat flux (CHF), fuel centerline temperature, and clad surface temperature and stress distribution. Finally, variously shaped fuel configurations, including cylindrical, triangular, square, and hexagonal, have been ranked according to the performance indicators.The hexagonal fuel pins, both twisted and straight, proved to be good solutions for the epithermal tight core of the light water-cooled IRIS reactor, with performances comparable to those of the cylindrical fuel with wires. In particular, for water-to-fuel ratios {approx}0.33, the twisted hexagonal shape is the preferable design with a reduction of the total pressure drop by 16% and an increase of the CHF margin by 200%, compared to the traditional cylindrical pins with grids. Furthermore, the straight hexagonal shape allows flatter subchannel velocity profiles, wall shear stress, and wall temperature distributions. However, geometric constraints unfortunately do not allow application of the twisted hexagonal shape for smaller water-to-fuel ratios, which is a design regime of more favorable epithermal neutronics performance. In this regime, the cylindrical pins with wires are the solution of choice.

Romano, Antonino; Todreas, Neil E. [Massachusetts Institute of Technology (United States)

2002-07-15

36

Simulation and experimental validation study on the drive performance of a new hydraulic power assist system  

Microsoft Academic Search

Hydraulic power assist system is a hydraulic regeneration system, which can improve fuel economy significantly coupled to a conventional bus operating in urban traffic. This paper presents a new hydraulic power assist system-HPAS. For the special configuration and control strategy, HPAS can be easily installed in an old bus as well as a new one. In this paper, more attention

Guo-Qing Liu; Ye-Cui Yan; Jie Chen; Tian-Ming Na

2009-01-01

37

Nuclear power plant thermal-hydraulic performance research program plan  

SciTech Connect

The purpose of this program plan is to present a more detailed description of the thermal-hydraulic research program than that provided in the NRC Five-Year Plan so that the research plan and objectives can be better understood and evaluated by the offices concerned. The plan is prepared by the Office of Nuclear Regulatory Research (RES) with input from the Office of Nuclear Reactor Regulation (NRR) and updated periodically. The plan covers the research sponsored by the Reactor and Plant Systems Branch and defines the major issues (related to thermal-hydraulic behavior in nuclear power plants) the NRC is seeking to resolve and provides plans for their resolution; relates the proposed research to these issues; defines the products needed to resolve these issues; provides a context that shows both the historical perspective and the relationship of individual projects to the overall objectives; and defines major interfaces with other disciplines (e.g., structural, risk, human factors, accident management, severe accident) needed for total resolution of some issues. This plan addresses the types of thermal-hydraulic transients that are normally considered in the regulatory process of licensing the current generation of light water reactors. This process is influenced by the regulatory requirements imposed by NRC and the consequent need for technical information that is supplied by RES through its contractors. Thus, most contractor programmatic work is administered by RES. Regulatory requirements involve the normal review of industry analyses of design basis accidents, as well as the understanding of abnormal occurrences in operating reactors. Since such transients often involve complex thermal-hydraulic interactions, a well-planned thermal-hydraulic research plan is needed.

Not Available

1988-07-01

38

Coupled Monte Carlo neutronics and thermal hydraulics for power reactors  

SciTech Connect

The availability of high performance computing resources enables more and more the use of detailed Monte Carlo models even for full core power reactors. The detailed structure of the core can be described by lattices, modeled by so-called repeated structures e.g. in Monte Carlo codes such as MCNP5 or MCNPX. For cores with mainly uniform material compositions, fuel and moderator temperatures, there is no problem in constructing core models. However, when the material composition and the temperatures vary strongly a huge number of different material cells must be described which complicate the input and in many cases exceed code or memory limits. The second problem arises with the preparation of corresponding temperature dependent cross sections and thermal scattering laws. Only if these problems can be solved, a realistic coupling of Monte Carlo neutronics with an appropriate thermal-hydraulics model is possible. In this paper a method for the treatment of detailed material and temperature distributions in MCNP5 is described based on user-specified internal functions which assign distinct elements of the core cells to material specifications (e.g. water density) and temperatures from a thermal-hydraulics code. The core grid itself can be described with a uniform material specification. The temperature dependency of cross sections and thermal neutron scattering laws is taken into account by interpolation, requiring only a limited number of data sets generated for different temperatures. Applications will be shown for the stationary part of the Purdue PWR benchmark using ATHLET for thermal- hydraulics and for a generic Modular High Temperature reactor using THERMIX for thermal- hydraulics. (authors)

Bernnat, W.; Buck, M.; Mattes, M. [Institut fuer Kernenergetik und Energiesysteme IKE, Universitaet Stuttgart, Pfaffenwaldring 31, D-70569 Stuttgart (Germany); Zwermann, W.; Pasichnyk, I.; Velkov, K. [Gesellschaft fuer Anlagen- und Reaktorsicherheit GRS MbH, Forschungszentrum, Boltzmannstrase 14, 85748 Garching (Germany)

2012-07-01

39

A Self-Contained Hydraulic Power Source for Artificial Upper Limbs  

Microsoft Academic Search

To provide a more independent alternative to the well established pneumatic artificial arm systems, body weight acting through small reciprocating pumps in the heels of the shoes is used as the power source for a self-contained hydraulic circuit. Energized by normal walking, hydraulic fluid is drawn from a flexible reservoir and delivered at high pressure to an hydraulic accumulator.

J. F. David Marsh; Ronald D. McLeish

1975-01-01

40

Hydraulically powered soil core sampler and its application to soil density and porosity estimation  

Microsoft Academic Search

The design of a hydraulically powered soil core sampler used to collect undisturbed soil samples at different depths in the field is presented. The hydraulic actuation of the coring probe reduces the physical effort and time required by the operators. The device is constructed from a three-point hitch frame equipped with a gearbox, retractable legs, hydraulic cylinder and probe. The

Nidal H Abu-Hamdeh; Hamid F Al-Jalil

1999-01-01

41

Hydraulics  

NSDL National Science Digital Library

These interactive learning objects, created by instructors from Fox Valley Technical College and other colleges in the Wisconsin Technical College program, focus on concepts that cover a broad-based electromechanical program. Here visitors will find learning objects in Hydraulics with over 25 lessons in Actuators, Relief Valves, Basic Concepts, and Directional Control Valves.

2011-01-03

42

46 CFR 111.97-5 - Electric and hydraulic power supply.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Electric and hydraulic power supply. 111.97-5 Section 111.97-5...Watertight Door Systems § 111.97-5 Electric and hydraulic power supply. (a) Each electric motor-driven door operating...

2010-10-01

43

46 CFR 111.97-5 - Electric and hydraulic power supply.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Electric and hydraulic power supply. 111.97-5 Section 111.97-5...Watertight Door Systems § 111.97-5 Electric and hydraulic power supply. (a) Each electric motor-driven door operating...

2009-10-01

44

Optimization of Power Management Strategies for a Hydraulic Hybrid Medium Truck  

Microsoft Academic Search

This paper investigates development of power management strategies tailored specifically to a medium truck with parallel hydraulic hybrid powertrain. The hydraulic hybrid vehicle (HHV) system is modeled in MATLAB\\/SIMULINK environment. As the starting point, this study considers rule-based power management strategy adopted from the previous HEV study. Dynamic Programming (DP) algorithm is used to find the optimal trajectories for gear

Bin Wu; Chan-Chiao Lin; Zoran Filipi; Huei Peng; Dennis Assanis

2002-01-01

45

Base-Bleed Effect on X-33 Aerospike Plume Induced Base-Heating Environment During Power-Pack Out.  

National Technical Information Service (NTIS)

A computational heat transfer methodology was developed to study the dual-engine linear aerospike plume induced base-heating environment during one power-pack out, in ascent flight. One power-pack out results in reduction of power levels for both engines....

T. S. Wang A. Droege M. D'Agostino Y. C. Lee R. Williams

2003-01-01

46

Optimal design of power-split transmissions for hydraulic hybrid passenger vehicles  

Microsoft Academic Search

Hydraulic hybrid vehicles are inherently power dense. Power-split or hydro-mechanical transmissions (HMT) have advantages over series and parallel architectures. In this paper, an approach for optimizing the configuration and sizing of a hydraulic hybrid power-split transmission is proposed. Instead of considering each mechanical configuration consisting of combinations of gear ratios, a generalized kinematic relation is used to avoid redundant computation.

Kai Loon Cheong; Perry Y. Li; Thomas R. Chase

2011-01-01

47

Investigation of Hydraulic Power Transmission Systems for V/STOL Aircraft.  

National Technical Information Service (NTIS)

A comparison is presented between the efficiency and weight of the UH-1 helicopter gear transmission and speed reducer systems to a hydraulic power transmitting system for the UH-1. The hydraulic transmission system is composed of a 'turbine speed' hydrau...

H. R. Crawford J. L. Overfield

1967-01-01

48

Design and analysis of a thermal hydraulic integral test facility for Bushehr nuclear power plant  

Microsoft Academic Search

In this paper, design and analysis of a thermal hydraulic integral test facility for Bushehr Nuclear Power Plant (NPP) is presented. The Bushehr Integral Test Facility (BITF) is a test facility designed to model the thermal-hydraulic behaviours of the Bushehr NPP (VVER-1000) pressurized water reactors currently in use in IRAN. These reactors have unique features that differ from other PWR

Toraj Khoshnevis; Jalil Jafari; Mostafa Sohrabpour

2009-01-01

49

Design of integrated electro-hydraulic power unit for hybrid mobile working machines  

Microsoft Academic Search

A high power density integrated non-overlapping concentrated tooth winding synchronous machine with embedded permanent magnets for a hydraulic motor-pump is designed. Direct liquid cooling with the working fluid itself is implemented. Aspects of immersing the motor into hydraulic oil for cooling purposes are discussed. FEM modelling of PM eddy-current losses and static temperature evaluation are performed.

Pavel Ponomarev; Maria Polikarpova; Olli Heinikainen; Juha Pyrhonen

2011-01-01

50

Uprated dc power system and thermal-hydraulic facilities at Columbia University. Final report  

Microsoft Academic Search

The necessity of carrying out large scale nuclear thermal-hydraulic simulations is increasing. Such experiments call for large power sources, and to meet those requirements the D.C. power system at the Heat Transfer Research Facility of Columbia University has been upgraded to 11.5 MW. The uprated system, its installations, various subsystems, and operations are described. The thermal-hydraulic loops and their auxiliary

W. E. Hovemeyer; S. R. Sreepada; J. E. Casterline

1978-01-01

51

Power generation costs and ultimate thermal hydraulic power limits in hypothetical advanced designs with natural circulation  

SciTech Connect

Maximum power limits for hypothetical designs of natural circulation plants can be described analytically. The thermal hydraulic design parameters are those which limit the flow, being the elevations, flow areas, and loss coefficients. WE have found some simple ``design`` equations for natural circulation flow to power ratio, and for the stability limit. The analysis of historical and available data for maximum capacity factor estimation shows 80% to be reasonable and achievable. The least cost is obtained by optimizing both hypothetical plant performance for a given output,a nd the plant layout and design. There is also scope to increase output and reduce cost by considering design variations of primary and secondary pressure, and by optimizing component elevations and loss coefficients. The design limits for each are set by stability and maximum flow considerations, which deserve close and careful evaluation.

Duffey, R.B.; Rohatgi, U.S.

1996-12-31

52

Study of hydraulic power recovery from New Mexico water distribution systems  

Microsoft Academic Search

The results of a survey of New Mexico water distribution systems suitable for hydroelectric power development are reported. The objectives of the survey were to determine the potential for hydraulic power recovery from existing and planned water systems, to identify potential sites, and to study and recommend promising sites for further development. The survey found eleven sites in New Mexico

Schoenmackers

1984-01-01

53

The Production of Electrochromatography Capillary Columns Using Gas Pressure Powered Dry-Packing Method  

Microsoft Academic Search

This paper introduces a dry-packing method of producing packed capillaries for using in capillary electrochromatography (CEC) or microbore HPLC. Several C18 packing materials with different particle size are studied. We compared the two methods of dry-packing and slurry-packing. The former yields analogous or better efficiency with a simpler apparatus using a shorter packing time. Besides, the columns are very stable

Changqiao Zhang; Chenfu Zhu; Xiuli Lin; Yunhe Wei

2003-01-01

54

High density 50 kW SiC inverter systems using a JFET based six-pack power module  

Microsoft Academic Search

Recent progress on Silicon Carbide (SiC) power devices has shown their better power conversion efficiency compared to Silicon power devices due to the significant reduction in both conduction and switching losses. Combined with their high operating junction temperature capability, six-pack SiC power modules have been developed for high reliable and compact power systems. This paper focuses on the development of

Timothy Junghee Han; Jim Nagashima; Sung Joon Kim; Srikanth Kulkarni; Fred Barlow

2011-01-01

55

Simulation of cavitation in rotary valve of hydraulic power steering gear  

Microsoft Academic Search

Hydraulic power steering gear supplies assistant power by liquid stream. The stream will be changed greatly for the flow field\\u000a formed by the rotary valve will vary during steering. And the change of the stream in this narrow field will (be big enough\\u000a to) cause the fluctuation of the assistance power and noise of the steering gear. 3-D meshes of

YaHui Liu; XueWu Ji

2009-01-01

56

Thermal-hydraulic calculations using MARS code applied to low power and shutdown probabilistic safety assessment in a PWR  

Microsoft Academic Search

The methods developed for full-power probabilistic safety assessment, including thermal-hydraulic methods, have been widely applied to low power and shutdown conditions. Experience from current low power and shutdown probabilistic safety assessments, however, indicates that the thermal-hydraulic methods developed for full-power probabilistic safety assessments are not always reliable when applied to low power and shutdown conditions and consequently may yield misleading

Young-Seok Son; Jee-Young Shin; Ho-Gon Lim; Jin-Hee Park; Seung-Cheol Jang

2005-01-01

57

Survey of thermal-hydraulic models of commercial nuclear power plants  

SciTech Connect

A survey of the thermal-hydraulic models of nuclear power plants has been performed to identify the NRC's current analytical capabilities for critical event response. The survey also supports ongoing research for accident management. The results of the survey are presented here. The PC database which records detailed data on each model is described.

Determan, J.C.; Hendrix, C.E.

1992-12-01

58

A mathematical model for the thermal-hydraulic analysis of nuclear power plants  

Microsoft Academic Search

The adequate dynamic models are developed for the thermal-hydraulic analysis of nuclear power plants with their fast running capacity on a personal computer. The dynamic models are formulated for the primary loop systems, coupling of reactor kinetics with the feedback reactivity, and the U-tube steam generator used in most pressurized water reactors. The main work is intended to demonstrate the

Gee Y. Han

2000-01-01

59

MURS-300 MK II: A remote inspection system for underwater facilities of hydraulic power plants  

Microsoft Academic Search

While the civil engineering facilities of hydraulic power plants such as dam, water intake, waterway, etc., are usually submerged, there are few effective methods for their inspection. So we at Mitsui Ocean Development and Engineering Co., Ltd. (MODEC) have developed a new remote-controlled inspection system named \\

Y. Tsusaka; H. Ishidera; Y. Itoh

1986-01-01

60

Interface design for the electrical and hydraulic control system of nuclear power plants  

Microsoft Academic Search

This study discusses the interface design of an automatic control system, the electrical and hydraulic control (EHC) system of nuclear power plants (NPPs) from two points of view, viz, how to identify information contents that should be displayed in an interface in a cognitive relevant way and how to visualize these information contents in the interface efficiently. Firstly, a set

Qiao Liu; Keiichi Nakata; Kazuo Furuta

2002-01-01

61

Hydraulic model study of the cooling lake for the La Salle County Nuclear Power Plant  

Microsoft Academic Search

A hydraulic model study of the cooling lake of the La Salle County Nuclear Power Station of Commonwealth Edison was performed. Two sizes of lake were investigated. In both cases various configurations of the internal, baffle-dike layout were studied to determine the configuration giving the best cooling performance. The experiments were performed by injecting a solution of Rhodamine WT fluorescent

J. C. Tatinclaux; S. C. Jain; W. W. Sayre

1973-01-01

62

Hydraulic Model Study of the Cooling Lake for the La Salle County Nuclear Power Plant.  

National Technical Information Service (NTIS)

A hydraulic model study of the cooling lake of the La Salle County Nuclear Power Station of Commonwealth Edison was performed. Two sizes of lake were investigated. In both cases various configurations of the internal, baffle-dike layout were studied to de...

J. C. Tatinclaux S. C. Jain W. W. Sayre

1973-01-01

63

Survey of thermal-hydraulic models of commercial nuclear power plants  

SciTech Connect

A survey of the thermal-hydraulic models of nuclear power plants has been performed to identify the NRC`s current analytical capabilities for critical event response. The survey also supports ongoing research for accident management. The results of the survey are presented here. The PC database which records detailed data on each model is described.

Determan, J.C.; Hendrix, C.E.

1992-12-01

64

Specifications for Selected Hydraulic-Powered Roof Supports with a Method to Estimate Support Requirements for Longwalls.  

National Technical Information Service (NTIS)

The report presents observations made regarding hydraulic-powered roof supports that are currently being used or have been used on nearly all operating longwalls in the United States. A comparative summary of specifications for various types of powered su...

A. J. Barry O. B. Nair J. S. Miller

1969-01-01

65

Thermal-Hydraulic Performance of Cross-Shaped Spiral Fuel in High-Power-Density BWRs  

Microsoft Academic Search

Power up-rating of existing nuclear reactors promises to be an area of great study for years to come. One of the major approaches to efficiently increasing power density is by way of advanced fuel design, and cross-shaped spiral-fuel has shown such potential in previous studies. Our work aims to model the thermal-hydraulic consequences of filling a BWR core with these

Thomas Conboy; Pavel Hejzlar

2006-01-01

66

Thermal-hydraulics for space power, propulsion, and thermal management system design  

Microsoft Academic Search

The present volume discusses thermal-hydraulic aspects of current space projects, Space Station thermal management systems, the thermal design of the Space Station Free-Flying Platforms, the SP-100 Space Reactor Power System, advanced multi-MW space nuclear power concepts, chemical and electric propulsion systems, and such aspects of the Space Station two-phase thermal management system as its mechanical pumped loop and its capillary

Krotiuk

1990-01-01

67

LVP modeling and dynamic characteristics prediction of a hydraulic power unit in deep-sea  

NASA Astrophysics Data System (ADS)

A hydraulic power unit (HPU) is the driving "heart" of deep-sea working equipment. It is critical to predict its dynamic performances in deep-water before being immerged in the seawater, while the experimental tests by simulating deep-sea environment have many disadvantages, such as expensive cost, long test cycles, and difficult to achieve low-temperature simulation, which is only used as a supplementary means for confirmatory experiment. This paper proposes a novel theoretical approach based on the linear varying parameters (LVP) modeling to foresee the dynamic performances of the driving unit. Firstly, based on the varying environment features, dynamic expressions of the compressibility and viscosity of hydraulic oil are derived to reveal the fluid performances changing. Secondly, models of hydraulic system and electrical system are accomplished respectively through studying the control process and energy transfer, and then LVP models of the pressure and flow rate control is obtained through the electro-hydraulic models integration. Thirdly, dynamic characteristics of HPU are obtained by the model simulating within bounded closed sets of varying parameters. Finally, the developed HPU is tested in a deep-sea imitating hull, and the experimental results are well consistent with the theoretical analysis outcomes, which clearly declare that the LVP modeling is a rational way to foresee dynamic performances of HPU. The research approach and model analysis results can be applied to the predictions of working properties and product designs for other deep-sea hydraulic pump.

Cao, Xue-peng; Ye, Min; Deng, Bin; Zhang, Cui-hong; Yu, Zu-ying

2013-03-01

68

PowerPACK: A wireless power distribution system for wearable devices  

Microsoft Academic Search

Motivated by the prevalence of small, battery-powered devices in many pervasive computing research and deployment scenarios, and the frustration encountered when a particular device is found to be useless due to a discharged internal battery, we present a backpack-worn wireless (non-contact) power distribution system. This system is designed to distribute power from a single point of generation or bulk storage

Travis Deyle; Matthew Reynolds

2008-01-01

69

Recognizing hydraulic power plant and aimpoint choosing from clutter background  

NASA Astrophysics Data System (ADS)

Large power stations are usually chosen as the target for missiles guided by IR seeker. This paper presents an aimpoint finding algorithm. The high light blob of boiler and straight lines of chimneys or water cooling towers are taken as the reference feature objects for locating and keeping the aimpoint form long to short distance. Some experiment results are given to show the validity of our method.

Li, Zhiyong; Yang, Weiping; Shen, Hai-Xin

1997-10-01

70

Simplified method of flow measurement in full-scale power tests of hydraulic units  

Microsoft Academic Search

Conclusions  \\u000a \\u000a \\u000a \\u000a 1. \\u000a \\u000a Verification of the simplified method for power tests on hydraulic units revealed that this method will produce the power\\u000a characteristics required for optimizing the regimes of hydroelectric plants.\\u000a \\u000a \\u000a \\u000a \\u000a 2. \\u000a \\u000a The simplified method makes it possible to reduce significantly the time required for the power tests and processing of the\\u000a data, as well as to lower the costs.

N. N. Kozhevnikov

1975-01-01

71

Asymmetric Base-Bleed Effect on Aerospike Plume-Induced Base-Heating Environment During Power-Pack Out.  

National Technical Information Service (NTIS)

A computational heat transfer design methodology was developed to study tbe dual-engine linear aerospike plume-induced base-heating environment during one power-pack out, in ascent flight. It includes a three-dimensional, finite volume, viscous, chemicall...

T. S. Wang A. Droege M. D'Agostino Y. C. Lee R. Williams

2003-01-01

72

Horizontal Steam Generator Thermal-Hydraulics at Various Steady-State Power Levels  

Microsoft Academic Search

Three-dimensional computer simulation and analyses of the horizontal steam generator thermal-hydraulics of the WWER 1000 nuclear power plant have been performed for 50% and 75% partial loads, 100% nominal load and 110% over-load. Presented results show water and steam mass flow rate vectors, steam void fraction spatial distribution, recirculation zones, swell level position, water mass inventory on the shell side,

Vladimir D. Stevanovic; Zoran V. Stosic; Michael Kiera; Uwe Stoll

2002-01-01

73

Vehicle having hydraulic and power steering systems using a single high pressure pump  

DOEpatents

A vehicle comprises a plurality of wheels attached to a vehicle housing. Also attached to the vehicle housing is a power steering system, including a fluid flow circuit, which is operably coupled to a number of the wheels. An internal combustion engine attached to the vehicle housing is connected to a hydraulically actuated system that includes a high pressure pump. An outlet of the high pressure pump is in fluid communication with the fluid flow circuit.

Bartley, Bradley E. (Manito, IL); Blass, James R. (Bloomington, IL); Gibson, Dennis H. (Chillicothe, IL)

2001-06-22

74

Thermal-hydraulic modeling and simulation of high power hydro-motor  

Microsoft Academic Search

Heat transfer analysis for a high power hydro-motor with cooling duct was given in the paper in which the heat flow inside the hydro-motor was described precisely. Based on the running characteristic of hydro-motor, the thermal model which could predict temperature charges of motorpsilas different parts was built. Hydraulic system with valve-controlled hydro-motor was taken as an example of the

Yonglin Li; Xinbing Su; Haojun Xu; Dawei Li

2008-01-01

75

[Application of ICP-AES in automotive hydraulic power steering system fault diagnosis].  

PubMed

The authors studied the innovative applications of the inductively coupled plasma-atomic emission spectrometry in automotive hydraulic power steering system fault diagnosis. After having determined Fe, Cu and Al content in the four groups of Buick Regal 2.4 main metal power-steering fluid whose travel course was respectively 2-9 thousand kilometers, 11-18 thousand kilometers, 22-29 thousandkilometers, and 31-40 thousand kilometers, and the database of primary metal content in the Buick Regal 2.4 different mileage power-steering fluid was established. The research discovered that the main metal content increased with increasing mileage and its normal level is between the two trend lines. Determination of the power-steering fluid main metal content and comparison with its database value can not only judge the wear condition of the automotive hydraulic power steering system and maintain timely to avoid the traffic accident, but also help the automobile detection and maintenance personnel to diagnose failure reasons without disintegration. This reduced vehicle maintenance costs, and improved service quality. PMID:23586258

Chen, Li-Dan

2013-01-01

76

Hydraulic Car  

NSDL National Science Digital Library

In this activity, learners build cars using syringes and water-powered hydraulics. Learners construct the car frame out of cardboard and set up a hydraulic system to raise and lower the car. Use this project to introduce learners to incompressible fluids and Pascal's Principle.

Workshop, Watsonville E.

2011-01-01

77

Numerical Hydraulic Study on Seawater Cooling System of Combined Cycle Power Plant  

NASA Astrophysics Data System (ADS)

As the rated flow and pressure increase in pumping facilities, a proper design against surges and severe cavitations in the pipeline system is required. Pressure surge due to start-up, shut-down process and operation failure causes the water hammer in upstream of the closing valve and the cavitational hammer in downstream of the valve. Typical cause of water hammer is the urgent closure of valves by breakdown of power supply and unexpected failure of pumps. The abrupt changes in the flow rate of the liquid results in high pressure surges in upstream of the valves, thus kinetic energy is transformed into potential energy which leads to the sudden increase of the pressure that is called as water hammer. Also, by the inertia, the liquid continues to flow downstream of the valve with initial speed. Accordingly, the pressure decreases and an expanding vapor bubble known as column separation are formed near the valve. In this research, the hydraulic study on the closed cooling water heat exchanger line, which is the one part of the power plant, is introduced. The whole power plant consists of 1,200 MW combined power plant and 220,000 m3/day desalination facility. Cooling water for the plant is supplied by sea water circulating system with a capacity of 29 m3/s. The primary focus is to verify the steady state hydraulic capacity of the system. The secondary is to quantify transient issues and solutions in the system. The circuit was modeled using a commercial software. The stable piping network was designed through the hydraulic studies using the simulation for the various scenarios.

Kim, J. Y.; Park, S. M.; Kim, J. H.; Kim, S. W.

2010-06-01

78

Research on the hydraulic turbine vertical vibration power flow in the head cover system  

NASA Astrophysics Data System (ADS)

On the basis of the prior models about the vertical vibration of the hydraulic vibration source, this research introduced a sub-system—head cover. Head cover is one of the main paths when vibration is transferred from the water vibration source to the stable structure. This essay aims to analyze the hydraulic turbine vertical vibration power flow in the head cover system. The research is based on the power flow theory and the probability perturbation method; meanwhile, it considered on the reciprocal coupling effect of the water machine parts and power house structure, etc. Therefore, the results of can clearly provide the random power flow of the vibration transfer path system, which including the head cover system, in frequency domain by given of some uncertain factors in one project. In conclusions, the research provide an overall analysis on the hydropower station vertical vibration transfer path; and it suggest some simplified and efficient solutions in the analysis on the vibration path with some random parameters.

Zhi, B. P.; Ma, Z. Y.

2012-11-01

79

Cavitation wear in hydraulic turbines at the Bratsk hydroelectric power plant  

Microsoft Academic Search

Conclusions  \\u000a \\u000a \\u000a \\u000a 1. \\u000a \\u000a A considerable cavitation wear of the runner blades at the Bratsk hydroelectric power plant occurred as the result of operating\\u000a the hydraulic turbines under conditions falling outside the design range and due to distortion of the blade profile caused\\u000a by electrode surfacing on a large scale carried out during repairs.\\u000a \\u000a \\u000a \\u000a \\u000a 2. \\u000a \\u000a The most effective method of reducing cavitation

I. S. Glukhov

1975-01-01

80

Thermal-hydraulics for space power, propulsion, and thermal management system design  

SciTech Connect

The present volume discusses thermal-hydraulic aspects of current space projects, Space Station thermal management systems, the thermal design of the Space Station Free-Flying Platforms, the SP-100 Space Reactor Power System, advanced multi-MW space nuclear power concepts, chemical and electric propulsion systems, and such aspects of the Space Station two-phase thermal management system as its mechanical pumped loop and its capillary pumped loop's supporting technology. Also discussed are the startup thaw concept for the SP-100 Space Reactor Power System, calculational methods and experimental data for microgravity conditions, an isothermal gas-liquid flow at reduced gravity, low-gravity flow boiling, computations of Space Shuttle high pressure cryogenic turbopump ball bearing two-phase coolant flow, and reduced-gravity condensation.

Krotiuk, W.J.

1990-01-01

81

High-Order Modeling of Hydraulic Power Plant in Islanded Power Network  

Microsoft Academic Search

Numerical simulations of the transient operation of an islanded power network subject to load rejections are performed. The islanded power network case study consists of a 1-GW hydroelectric power plant featuring four generating units, a long penstock, and a surge tank connected to four 1.3-GW thermal power plants and passive consumers. The modeling of every network component is described and

Christophe Nicolet; Bob Greiveldinger; Jean Jacques Herou; Basile Kawkabani; Philippe Allenbach; Jean-Jacques Simond

2007-01-01

82

Loss of offsite power in pressurized water reactors: a combined probabilistic and thermal-hydraulic analysis  

SciTech Connect

The Pressurized Water Reactor (PWR) loss of offsite power initiating event was studied at the Idaho National Engineering Laboratory as a part of the US Nuclear Regulatory Commission's (NRC) Severe Accident Sequence Analysis Program. An event tree was developed and used as a basis for investigating high risk accident sequences initiated by a loss of offsite power. Specific high risk sequences for further study were determined by assigning probabilities to events within the tree. The thermal-hydraulic responses of three PWRs of different vendors were calculated for these high risk sequences using the RELAP4/MOD7 computer code. Actions to mitigate the consequences of certain sequences were identified and the critical times for their implementation were determined. 2 refs., 6 figs., 2 tabs.

Fletcher, C.D.; Bruske, S.J.

1981-01-01

83

Thermal-hydraulic tests of a recirculation cooling installation for the Rostov nuclear power station  

NASA Astrophysics Data System (ADS)

Results obtained from thermal-hydraulic tests of the recirculation cooling installation used as part of the air cooling system under the containments of the Rostov nuclear power station Units 3 and 4 are presented. The operating modes of the installation during normal operation (air cooling on the surface of finned tubes), under the conditions of anticipated operational occurrences (air cooling and steam condensation from a steam-air mixture), and during an accident (condensation of pure steam) are considered. Agreement is obtained between the results of tests and calculations carried out according to the recommendations given in the relevant regulatory documents. A procedure of carrying out thermal calculation for the case of steam condensation from a steam-air mixture on the surface of fins is proposed. The possibility of efficient use of the recirculation cooling installation in the system for reducing emergency pressure under the containment of a nuclear power station is demonstrated.

Balunov, B. F.; Balashov, V. A.; Il'in, V. A.; Krayushnikov, V. V.; Lychakov, V. D.; Meshalkin, V. V.; Ustinov, A. N.; Shcheglov, A. A.

2013-09-01

84

Current evaluation of hydraulics to replace the cable force transmission system for body-powered upper-limb prostheses.  

PubMed

Present body-powered upper-limb prostheses use a cable control system employing World War II aircraft technology to transmit force from the body to the prosthesis for operation. The cable and associated hardware are located outside the prosthesis. Because individuals with arm amputations want prostheses that are natural looking with a smooth, soft outer surface, a design and development project was undertaken to replace the cable system with hydraulics located inside the prosthesis. Three different hydraulic transmission systems were built for evaluation, and other possibilities were explored. Results indicate that a hydraulic force transmission system remains an unmet challenge as a practical replacement for the cable system. The author was unable to develop a hydraulic system that meets the necessary dynamic requirements and is acceptable in size and appearance. PMID:10149042

LeBlanc, M

1990-01-01

85

Thermal-Hydraulic Performance of Cross-Shaped Spiral Fuel in High-Power-Density BWRs  

SciTech Connect

Power up-rating of existing nuclear reactors promises to be an area of great study for years to come. One of the major approaches to efficiently increasing power density is by way of advanced fuel design, and cross-shaped spiral-fuel has shown such potential in previous studies. Our work aims to model the thermal-hydraulic consequences of filling a BWR core with these spiral-shaped pins. The helically-wound pins have a cross-section resembling a 4-petaled flower. They fill an assembly in a tight bundle, their dimensions chosen carefully such that the petals of neighboring pins contact each other at their outer-most extent in a self-supporting lattice, absent of grid spacers. Potential advantages of this design raise much optimism from a thermal-hydraulic perspective. These spiral rods possess about 40% larger surface area than traditional rods, resulting in increased cooling and a proportional reduction in average surface heat flux. The thin petal-like extensions help by lowering thermal resistance between the hot central region of the pin and the bulk coolant flow, decreasing the maximum fuel temperature by 200 deg. C according to Finite Element (COSMOS) models. However, COSMOS models also predict a potential problem area at the 'elbow' region of two adjoining petals, where heat flux peaking is twice that along the extensions. Preliminary VIPRE models, which account only for the surface area increase, predict a 22% increase in critical power. It is also anticipated that the spiral twist would provide the flowing coolant with an additional radial velocity component, and likely promote turbulence and mixing within an assembly. These factors are expected to provide further margin for increased power density, and are currently being incorporated into the VIPRE model. The reduction in pressure drop inherent in any core without grid-spacers is also expected to be significant in aiding core stability, though this has not yet been quantified. Spiral-fuel seems to be a favorable alternative to traditional pins from a thermal-hydraulic standpoint, though further study of the trends shown in this paper are required. (authors)

Conboy, Thomas; Hejzlar, Pavel [Massachusetts Institute of Technology, 77 massachusetts avenue cambridge, ma 02139-4307 (United States)

2006-07-01

86

Power function decay of hydraulic conductivity for a TOPMODEL-based infiltration routine  

NASA Astrophysics Data System (ADS)

TOPMODEL rainfall-runoff hydrologic concepts are based on soil saturation processes, where soil controls on hydrograph recession have been represented by linear, exponential, and power function decay with soil depth. Although these decay formulations have been incorporated into baseflow decay and topographic index computations, only the linear and exponential forms have been incorporated into infiltration subroutines. This study develops a power function formulation of the Green and Ampt infiltration equation for the case where the power n = 1 and 2. This new function was created to represent field measurements in the New York City, USA, Ward Pound Ridge drinking water supply area, and provide support for similar sites reported by other researchers. Derivation of the power-function-based Green and Ampt model begins with the Green and Ampt formulation used by Beven in deriving an exponential decay model. Differences between the linear, exponential, and power function infiltration scenarios are sensitive to the relative difference between rainfall rates and hydraulic conductivity. Using a low-frequency 30 min design storm with 4.8 cm h-1 rain, the n = 2 power function formulation allows for a faster decay of infiltration and more rapid generation of runoff. Infiltration excess runoff is rare in most forested watersheds, and advantages of the power function infiltration routine may primarily include replication of field-observed processes in urbanized areas and numerical consistency with power function decay of baseflow and topographic index distributions. Equation development is presented within a TOPMODEL-based Ward Pound Ridge rainfall-runoff simulation. Copyright

Wang, Jun; Endreny, Theodore A.; Hassett, James M.

2006-11-01

87

RELAP5 thermal-hydraulic analysis of the SNUPPS (Standardized Nuclear Unit Power Plant System) pressurized water reactor  

Microsoft Academic Search

Thermal-hydraulic analyses of five hypothetical accident scenarios were performed with the RELAP5 computer code for the Westinghouse Standardized Nuclear Unit Power Plant System pressurized water reactor. This work was sponsored by the US Nuclear Regulatory Commission and is being done in conjunction with future analysis work at the US Nuclear Regulatory Commission Technical Training Center in Chattanooga, TN. These accident

Kullberg

1990-01-01

88

INVESTIGATION OF A MONOPROPELLANT POWERED FREE PISTON HYDRAULIC PUMP PART 1: THEORETICAL ANALYSIS AND EXPERIMENTAL VERIFICATION1  

Microsoft Academic Search

The authors present a novel power supply for mobile robotic systems. Monopropellant fuel (e.g. hydrogen peroxide) decomposes into high temperature gases, which drive a free piston pump hydraulic pump (FPHP). The elimination of fuel\\/oxidizer mixing allows the design of simple, lightweight systems capable of operation in oxygen free environments. A thermodynamic analysis has been performed, and an experimental FPHP has

Timothy G. McGee; Justin W. Raade; Homayoon Kazerooni

89

Numerical Analysis of the Interaction between Hydraulic Powered Support and Surrounding Rock Strata at Indian Longwall Faces  

Microsoft Academic Search

Longwall mining is the only technically proven and established method worldwide for coal extraction at greater depth. In this paper, 2D plane strain finite element models of longwall panels are developed and analyzed to understand the interaction of hydraulic powered support with surrounding rock strata. Based on Indian geomining conditions, finite element models are developed including the structural components of

A. K. Verm; D. De

90

American Recovery & Reinvestment Act: Fuel Cell Hybrid Power Packs and Hydrogen Refueling for Lift Trucks  

SciTech Connect

HEB Grocery Company, Inc. (H-E-B) is a privately-held supermarket chain with 310 stores throughout Texas and northern Mexico. H-E-B converted 14 of its lift reach trucks to fuel cell power using Nuvera Fuel Cells’ PowerEdge™ units to verify the value proposition and environmental benefits associated with the technology. Issues associated with the increasing power requirements of the distribution center operation, along with high ambient temperature in the summer and other operating conditions (such as air quality and floor surface condition), surfaced opportunities for improving Nuvera’s PowerEdge fuel cell system design in high-throughput forklift environments. The project included on-site generation of hydrogen from a steam methane reformer, called PowerTap™ manufactured by Nuvera. The hydrogen was generated, compressed and stored in equipment located outside H-E-B’s facility, and provided to the forklifts by hydrogen dispensers located in high forklift traffic areas. The PowerEdge fuel cell units logged over 25,300 operating hours over the course of the two-year project period. The PowerTap hydrogen generator produced more than 11,100 kg of hydrogen over the same period. Hydrogen availability at the pump was 99.9%. H-E-B management has determined that fuel cell forklifts help alleviate several issues in its distribution centers, including truck operator downtime associated with battery changing, truck and battery maintenance costs, and reduction of grid electricity usage. Data collected from this initial installation demonstrated a 10% productivity improvement, which enabled H-E-B to make economic decisions on expanding the fleet of PowerEdge and PowerTap units in the fleet, which it plans to undertake upon successful demonstration of the new PowerEdge reach truck product. H-E-B has also expressed interst in other uses of hydrogen produced on site in the future, such as for APUs used in tractor trailers and refrigerated transport trucks in its fleet.

Block, Gus

2011-07-31

91

The application of computational fluid dynamics for determining the hydraulic characteristics of pipelines at nuclear power stations  

Microsoft Academic Search

The application of computational fluid dynamics for calculating the hydraulic resistances of elements of the pipeline system\\u000a for steam and gas discharges at a nuclear power station equipped with an RBMK-1000 reactor is demonstrated. It is shown that\\u000a the interaction of local resistances along the flow path that are situated close to one another at distances insufficient\\u000a for the flow

O. Yu. Novosel’skii; V. E. Petrov; A. P. Skibin; S. L. Solov’ev; A. V. Shishov

2006-01-01

92

Wind Power Plants. Hydraulic Transmission with Control Systems for Unrestricted Number of Revolutions.  

National Technical Information Service (NTIS)

Basic ideas are presented for the design of a hydraulic transmission with its control system adapted to an electric generator operated by a wind turbine with unrestricted revolutions. The settlement of the principle is shown by means of commercially avail...

R. Andersson

1976-01-01

93

American Recovery and Reinvestment Act: Fuel Cell Hybrid Power Packs and Hydrogen Refueling for Lift Trucks.  

National Technical Information Service (NTIS)

H.E.B. Grocery Company, Inc. (H-E-B) is a privately-held supermarket chain with 310 stores throughout Texas and northern Mexico. The company converted 14 of its lift reach trucks to fuel cell power to verify the value proposition and environmental benefit...

G. Block H. E. Butt

2012-01-01

94

Reducing Delay and Power Consumption of the Wakeup Logic Through Instruction Packing and Tag Memoization  

Microsoft Academic Search

Dynamic instruction scheduling logic is one of the most critical components of modern superscalar microprocessors, both from the delay and power dissipation standpoints. The delay and energy requirement of driving the result tags across the associatively-addressed issue queue accounts for a significant percentage of the scheduler's overhead and also limits the design scalability. We propose two schemes to reduce the

Joseph J. Sharkey; Dmitry Ponomarev; Kanad Ghose; Oguz Ergin

2004-01-01

95

Treatment of screened dairy manure by upflow anaerobic fixed bed reactors packed with waste tyre rubber and a combination of waste tyre rubber and zeolite: effect of the hydraulic retention time.  

PubMed

Two laboratory-scale anaerobic fixed bed reactors were evaluated while treating dairy manure at upflow mode and semicontinuous feeding. One reactor was packed with a combination of waste tyre rubber and zeolite (R1) while the other had only waste tyre rubber as a microorganism immobilization support (R2). Effluent quality improved when the hydraulic retention time (HRT) increased from 1.0 to 5.5 days. Higher COD, BOD5, total and volatile solids removal efficiencies were always achieved in the reactor R1. No clogging was observed during the operation period. Methane yield was also a function of the HRT and of the type of support used, and was 12.5% and 40% higher in reactor R1 than in R2 for HRTs of 5.5 and 1.0 days, respectively. The results obtained demonstrated that this type of reactor is capable of operating with dairy manure at a HRT 5 times lower than that used in a conventional reactor. PMID:18280149

Umaña, Oscar; Nikolaeva, Svetlana; Sánchez, Enrique; Borja, Rafael; Raposo, Francisco

2008-02-14

96

Single-shaft combined cycle packs power in at low cost  

SciTech Connect

Worldwide demand for combined cycle (CC) powerplants has grown exponentially over the past decade, and most forecasts call for the boom to continue. Reasons, by now, are clear: the CC powerplant--in its basic form, a gas turbine exhausting into a heat-recovery steam generator (HRSG) that supplies a steam turbine--is the most efficient electric generating system commercially available today. It also exhibits capital costs significantly lower than competing nuclear, fossil-fired steam, and renewable-energy stations. In addition, its low air emissions, water consumption, space requirements, and physical profile are no trifling advantages in an era marked by tough permitting and siting processes. A relatively recent advance that may further cement the CC`s front-running position is combining the gas turbine, steam turbine, and electric generator on a single shaft. Locking together the turbines and generator to form one single-train operating system promises to simplify plant design and operation, and may lower first costs. Trade-offs of the single-shaft approach, however, include the need for higher starting power and less operating flexibility, particularly if no synchronous clutch is used between the gas and steam turbine. Also worth noting: the arrangement takes away the phased construction option where a simple-cycle gas turbine is installed first and the steam cycle is added later. But depending on project specifics, the rewards of the single-shaft CC can outweigh its drawbacks, as a look at several recent installations reveals in this article.

Swanekamp, R.

1996-01-01

97

Novel Repair Technique for Life-Extension of Hydraulic Turbine Components in Hydroelectric Power Stations  

Microsoft Academic Search

A significant number of hydraulic turbines operated in Japan were installed in the first half of the 20th century. Today, aging degradation and flaws are observed in these turbine equipments. So far, Japanese engineers have applied NDI technology of Ultrasonic Testing (UT) to detect the flaws, and after empirical evaluation of the remaining life they decided an adequate moment to

Yoichi Hiramatsu; Jun Ishii; Kazuhiro Funato

2008-01-01

98

HYDRAULIC POWER TRANSFER SYSTEMS. AGRICULTURAL MACHINERY--SERVICE OCCUPATIONS, MODULE NUMBER 9.  

ERIC Educational Resources Information Center

|ONE OF A SERIES DESIGNED TO HELP TEACHERS PREPARE POSTSECONDARY-LEVEL STUDENTS FOR THE AGRICULTURAL MACHINERY SERVICE OCCUPATIONS AS PARTS MEN, MECHANICS, MECHANIC'S HELPERS, AND SERVICE SUPERVISORS, THIS GUIDE AIMS TO DEVELOP STUDENT COMPETENCY IN UNDERSTANDING BASIC HYDRAULICS AND ITS APPLICATION TO AGRICULTURAL MACHINERY. IT WAS DEVELOPED BY A…

Ohio State Univ., Columbus. Center for Vocational and Technical Education.

99

Thermal-hydraulics Analysis of a Radioisotope-powered Mars Hopper Propulsion System  

Microsoft Academic Search

Thermal-hydraulics analyses results produced using a combined suite of computational design and analysis codes are presented for the preliminary design of a concept Radioisotope Thermal Rocket (RTR) propulsion system. Modeling of the transient heating and steady state temperatures of the system is presented. Simulation results for propellant blow down during impulsive operation are also presented. The results from this study

Robert C. OBrien; Andrew C. Klein; William T. Taitano; Justice Gibson; Brian Myers; Steven D. Howe

2011-01-01

100

HYDRAULIC CONDUCTIVITY OF ESSENTIALLY SATURATED PEAT  

SciTech Connect

The Savannah River National Laboratory measured the hydraulic conductivity of peat samples using method ASTM D4511-00. Four samples of peat were packed into 73mm diameter plastic tubes and saturated from the bottom up with water. The columns were packed with Premier ProMoss III TBK peat to a dry density of approximately 0.16 gm/cc (10 lb/ft3). One column was packed using oven dried peat and the other 3 were packed using as delivered peat. The oven dried sample was the most difficult to saturate. All of the peat samples expanded during saturation resulting in a sample length (L) that was longer than when the sample was initially packed. Table 1 contains information related to the column packing. After saturation the hydraulic conductivity test was conducted using the apparatus shown in Figure 1. Three of the samples were tested at 2 different flow conductions, 1 high and 1 low. Table 2 and Figure 2 contain the results of the hydraulic conductivity testing. Each test was run for a minimum of 40 minutes to allow the test conditions to stabilize. The hydraulic conductivity at the end of each test is reported as the hydraulic conductivity for that test. The hydraulic conductivity of the 4 peat samples is 0.0052 {+-} 0.0009 cm/sec. This result compares well with the hydraulic conductivity measured in the pilot scale peat bed after approximately 2 months of operation. The similarity in results between the dry pack sample and moist pack samples shows the moisture content at the time of packing had a minimal effect on the hydraulic conductivity. Additionally, similarity between the results shows the test is reproducible. The hydraulic conductivity results are similar to those reported by other tests of peat samples reported in the literature.

Nichols, R

2008-02-27

101

Reactor thermal-hydraulic FY 1986 status report for the multimegawatt Space Nuclear Power Program  

SciTech Connect

PNL's 1986 activities can be divided into three basic areas: code assessment, correlation assessment and experimental activities. The ultimate goal of all these activities is developing computer codes and verifying their use to perform the thermal-hydraulic analysis and design of the reactor core and plenum of the various proposed concepts. To perform this task as assessment is made of existing computer codes, models, correlations, and microgravity experimental data.

Krotiuk, W.J.; Antoniak, Z.I.

1986-10-01

102

Thermal-hydraulics Analysis of a Radioisotope-powered Mars Hopper Propulsion System  

SciTech Connect

Thermal-hydraulics analyses results produced using a combined suite of computational design and analysis codes are presented for the preliminary design of a concept Radioisotope Thermal Rocket (RTR) propulsion system. Modeling of the transient heating and steady state temperatures of the system is presented. Simulation results for propellant blow down during impulsive operation are also presented. The results from this study validate the feasibility of a practical thermally capacitive RTR propulsion system.

Robert C. O'Brien; Andrew C. Klein; William T. Taitano; Justice Gibson; Brian Myers; Steven D. Howe

2011-02-01

103

PATHFINDER ATOMIC POWER PLANT. HYDRAULIC ANALYSIS OF PATHFINDER BOILE. Summary Report  

Microsoft Academic Search

A hydraulic analysis of the Pathfinder boiler core was completed. A ;\\u000a description of flow paths including a schematic diagram is included. Pressure ;\\u000a drops along primary and leakage fiow paths were calculatsd. After the resistance ;\\u000a of each of the leakage paths was identified and the available driving forces in ;\\u000a terms of pressure drops associated with the active

Sher

1961-01-01

104

Hydraulic resistance and convective heat transfer within independent power generation micro sources (IPM) channels  

NASA Astrophysics Data System (ADS)

The introduction of new structural materials and technologies contributes to the efficiency increase for the compact IPMs used in various branches of engineering. Use of a driving high-temperature (TIT600K), regenerative (the regeneration ratio is E>85%) micro gas turbine engine ?GTE, major components which are made of structural ceramics, allows not only to maintain the effective efficiency at ?e=26-30%, but, also, sharply reduce the material consumption rate for the micro source as a whole. Application of the laser prototyping technique to manufacture the air heater, which is a part of ?GTE, increases the IPM compactness. Miniaturization of the air heater, manufactured by the structural ceramics laser fusion, can significantly reduce the hydraulic diameter (dh<=1.0 mm) of the channels, designed to transport the working media inside it. Reducing dh leads to a significant increase in the hydraulic resistance of the micro channels. The associated increase in the energy consumption for ?GTE's own needs is compensated by increasing the TIT, E, and heat transfer coefficients in micro channels, and by eliminating the need in cooling for high temperature IPM components.

V, Sudarev A.; V, Sudarev B.; A, Suryaninov A.

2012-05-01

105

Novel Repair Technique for Life-Extension of Hydraulic Turbine Components in Hydroelectric Power Stations  

NASA Astrophysics Data System (ADS)

A significant number of hydraulic turbines operated in Japan were installed in the first half of the 20th century. Today, aging degradation and flaws are observed in these turbine equipments. So far, Japanese engineers have applied NDI technology of Ultrasonic Testing (UT) to detect the flaws, and after empirical evaluation of the remaining life they decided an adequate moment to replace the equipments. Since the replacement requires a large-scale field site works and high-cost, one of the solutions for life-extension of the equipments is introduction of repair services. We have been working in order to enhance the accuracy of results during the detection of flaws and flaws dimensioning, in particular focusing on the techniques of Tip-echo, TOFD and Phased-Array UT, accompanied by the conventional UT. These NDI methods made possible to recognize the entire image of surface and embedded flaws with complicated geometry. Then, we have developed an evaluation system of these flaws based on the theory of crack propagation, of the logic of crack growth driven by the stress-intensity factor of the crack tip front. The sophisticated evaluation system is constituted by a hand-made software and database of stress-intensity factor. Based on these elemental technologies, we propose a technique of repair welding to provide a life-extension of hydraulic turbine components.

Hiramatsu, Yoichi; Ishii, Jun; Funato, Kazuhiro

106

Method for dense packing discovery  

NASA Astrophysics Data System (ADS)

The problem of packing a system of particles as densely as possible is foundational in the field of discrete geometry and is a powerful model in the material and biological sciences. As packing problems retreat from the reach of solution by analytic constructions, the importance of an efficient numerical method for conducting de novo (from-scratch) searches for dense packings becomes crucial. In this paper, we use the divide and concur framework to develop a general search method for the solution of periodic constraint problems, and we apply it to the discovery of dense periodic packings. An important feature of the method is the integration of the unit-cell parameters with the other packing variables in the definition of the configuration space. The method we present led to previously reported improvements in the densest-known tetrahedron packing. Here, we use the method to reproduce the densest-known lattice sphere packings and the best-known lattice kissing arrangements in up to 14 and 11 dimensions, respectively, providing numerical evidence for their optimality. For nonspherical particles, we report a dense packing of regular four-dimensional simplices with density ?=128/219?0.5845 and with a similar structure to the densest-known tetrahedron packing.

Kallus, Yoav; Elser, Veit; Gravel, Simon

2010-11-01

107

APPLICATION OF MIKE PACKAGE TO ASSESS HYDRAULIC REGIMES AND FLOOD MAPPING WHEN CONSTRUCTION OF THERMAL POWER AT THE MONG DUONG ESTUARY (QUANG NINH)  

Microsoft Academic Search

The article presents the results formulated the effect to hydraulic regimes and inundated areas when construction of thermal power factory at the estuary of Mong Duong river by using the package of MIKE including Mike NAM, Mike11-HD and Mike-GIS with 2 options of canal width as well its location. The simulated results show that Mike package seems feasibly to formulate

VU MINH CAT; BUI DU DUONG

2007-01-01

108

Performance of Hydraulic Structures at the Kamskaya Hydroelectic Power Plant: Inspection Report as of June 2002  

Microsoft Academic Search

The Kamskaya Hydroelectric Power Plant (KHPP) on the Kama river is an upstream integrated hydro system in the Volga–Kama series of hydroelectric stations. The KHPP is located within the confines of the city of Perm, 3 km downstream the Chusovaya river estuary, a left-side stream of the Kama river. Functionally, the KHPP was mainly intended to generate electric power and

E. A. Kogan

2003-01-01

109

Mathematical model of electric hydraulic and powered support control system at a plough mining face  

Microsoft Academic Search

Given the actual working of a fully mechanized plough at a mining face, we have proposed a formula for running constraints between powered supports and a coal plough under assumed geological conditions of the coal face and, on this basis, established an automatic control model of powered supports for the coal plough face. We introduced the working principle of the

Wei ZHANG; Xiao HAN; Jing-jing SUN

2008-01-01

110

Transient Test of a NSSS Thermal-Hydraulic Module for the Nuclear Power Plant Simulator Using a Best-Estimate Code, RETRAN  

Microsoft Academic Search

\\u000a Korea Electric Power Research Institute (KEPRI) developed real-time simulation Thermal hydraulic model (ARTS) which is based\\u000a on the best-estimate code, RETRAN. It was adapted Kori unit 1 nuclear power plant analyzer (NPA). This paper describes the\\u000a result of the some of steady and transient tests of the Kori unit 1 NPA. The simulated results are compared and reviewed with\\u000a the

Myeong-soo Lee; In-yong Seo; Yo-han Kim; Yong-kwan Lee; Jae-seung Suh

2004-01-01

111

Valuation about remaining service life of GBM hydraulic power plant units technical and economical aspects  

Microsoft Academic Search

The importance of “Governador Bento Munhoz da Rocha Neto-GBM Power Plant”, its time in service and its operating conditions render it necessary to assess the generators' remaining service life. It was also considered appropriate to review the operating conditions relating them with the economical aspects involved. Based on a model proposed by H. Yoshida and K. Uemoto (1986) and in

T. P. Hara; L. F. L. Vianna; E. E. Nachvalger; E. Goncalves

1994-01-01

112

Basic Modeling and Simulation Tool for Analysis of Hydraulic Transients in Hydroelectric Power Plants  

Microsoft Academic Search

In this paper, the simulation system of a typical hydroelectric power plant was developed in a MATLAB\\/Simulink-based software environment, which has a high water head and a long penstock with upstream and downstream surge tanks and is equipped with a Francis turbine. With MATLAB\\/Simulink, the models of the proposed simulation system are all modularized and visualized, and can be reused

Hongqing Fang; Long Chen; Nkosinathi Dlakavu; Zuyi Shen

2008-01-01

113

Special Electro-Hydraulic Valve for Hydro-Viscous Drive Used in Thermal Power Generation Plant  

Microsoft Academic Search

When applied on the pulverized coal blowers or water-feeding pumps which are driven by huge electrical motors in one thermal power generation plant, acting as a kind of the soft start-up device, hydro-viscous drive (HVD) can help to save a lot of energy. The principle and structure of HVD is introduced in the paper. Through theoretical analysis of the HVD

Ning Chen

2009-01-01

114

Investigation of alternate power source for Space Shuttle Orbiter hydraulic system  

NASA Astrophysics Data System (ADS)

This investigation consists of a short-term feasibility study to determine whether or not an alternate electrical power source would trade favorably from a performance, reliability, safety, operation, and weight standpoint in replacing the current auxiliary power unit subsystems with its attendant components (water spray boiler, hydrazine fuel and tanks, feed and vent lines, controls, etc.), operating under current flight rules. Results of this feasibility study are used to develop recommendations for the next step (e.g., to determine if such an alternate electrical power source would show an advantage given that the current operational flight mode of the system could be modified in such a way as not to constrain the operational capability and safety of the vehicle). However, this next step is not within the scope of this investigation. This study does not include a cost analysis, nor does it include investigation of the integration aspects involved in such a trade, except in a qualitative sense for the determination of concept feasibility.

Simon, William E.; Young, Fred M.

1993-05-01

115

THE PACKING SIMULATION MODEL  

Microsoft Academic Search

The Packing Simulation Model is a microcomputer application program designed for researchers, extension personnel, bankers, packing managers, or other specialists who plan the operations of a packing facility or simulate its financial performance. PACKSIM produces pro forma financial statements for packing facilities based on flexible crop mixes and packing assumptions. Variations can be made in the product harvest schedule, price,

Constance L. Falk; Daniel S. Tilley; Raymond Joe Schatzer

1987-01-01

116

Hydraulic motor for cars  

SciTech Connect

A hydraulic motor for a car is described comprising, in combination, an automotive vehicle engine for travel self-propulsion, including a block, a plurality of cylinders in the block, a piston slidable in each cylinder, a crankshaft in the block, a piston rod connected between the crankshaft and each of the pistons, a power take-off gear on the crankshaft for the travel self-propulsion, and the engine including a hydraulic means for driving the pistons in the cylinders.

Gagnon, D.C.

1986-09-02

117

Vacuum excavation, hydraulics combined by consumers power in a do-everything multi-purpose vehicle  

SciTech Connect

A multi-purpose maintenance vehicle is described that is productive, efficient, mobile, flexible and economical. Three such vehicles are currently in operation in the Consumers Power system in Michigan. Some advantages are listed and include: only a twoman crew required; vehicles equipped for all types of repair and maintenance operations; safer because there is no moving boom; inconvenience to public/pedestrians/vehicles are minimized; and shoring is eliminated. Several tasks are listed which may be performed by the vehicle: cast iron pipe bell joint repair; leak clamp applications; service line abandonments; service line renewals; anode, test wire, and bond wire installations; curb box and valve box cleaning; and checking for and venting leaks.

Hale, D.

1985-11-01

118

Numerical analysis of aerodynamics and hydraulic loss in the GTÉ-150 combustion chamber of gas-turbine power plant with the use of the fluent suite  

Microsoft Academic Search

The aerodynamic structure of the flow in the combustion chamber of the GTÉ-150 gas-turbine power plant has been simulated\\u000a numerically by means of the FLUENT suite CFD. The influence of the processes of turbulent heat and mass transfer (and combustion)\\u000a on the hydraulic loss in the combustion chamber has been investigated. Detailed comparison of the calculated and experimental\\u000a data on

D. A. Lysenko; A. A. Solomatnikov

2006-01-01

119

Evaluation of Army engine oils in hydraulic\\/power-transmission-system components. Final report, August 1984November 1985  

Microsoft Academic Search

The objective of the MACI Hydraulic System and Components Program is to perform technical evaluation and assessment of commerically available qualified and fielded Army engine oils and to determine if such oils can be used as hydraulic fluids in Army commercial construction equipment and material-handling equipment. Five Army specification engine lubricants--four MIL-L-2104D (one grade 10W, one grade 30, two grade

H. W. Marbach; S. J. Lestz

1985-01-01

120

Technical-Evaluation Report on the Proposed Technical-Specification Changes for the Inservice Surveillance of Safety-Related Hydraulic and Mechanical Snubbers at the Maine Yankee Nuclear Power Plant (Docket No. 50-309).  

National Technical Information Service (NTIS)

This report documents the technical evaluation of the proposed Technical Specification changes to Limiting Conditions for Operation, Surveillance Requirements and Bases for safety-related hydraulic and mechanical snubbers at the Maine Yankee Nuclear Power...

J. C. Selan

1983-01-01

121

Technical-Evaluation Report on the Proposed Technical-Specification Changes for the Inservice Surveillance of Safety-Related Hydraulic and Mechanical Snubbers at the Indian Point Nuclear Power Plant, Unit 3 (Docket No. 50-286).  

National Technical Information Service (NTIS)

This report documents the technical evaluation of the proposed Technical Specification changes to Limiting Conditions for Operation, Surveillance Requirements and Bases for safety-related hydraulic and mechanical snubbers at the Indian Point Nuclear Power...

J. C. Selan

1983-01-01

122

Applied research on extension element model in hydraulic system  

NASA Astrophysics Data System (ADS)

This paper further researches the application of extension element model of hydraulic system. A extension element model of hydraulic system contains three parts: the prototype of a hydraulic component, the matter-element and relationelement model of hydraulic components, and the matter-element and relation-element model of hydraulic systems. The foundation building a extension element model of hydraulic system is to build its database of the prototypes of a hydraulic component. The matter-element and relation-element model of hydraulic components is a model for physical hydraulic components. The the matter-element and relation-element models of hydraulic components on a hydraulic system can describe the internal links among hydraulic components. Through analysis of the connections among the matter-element and relation-element models of hydraulic components, rings, power bond graphs, and dynamic equations will be found and gained. Thus, the performance and digital simulation for a hydraulic system will be realized and finished.

Tian, Junying; Wei, Bingyang; Han, Jianhai

2010-08-01

123

Improved Online Hypercube Packing  

Microsoft Academic Search

In this paper, we study online multidimensional bin packing problem when all items are hypercubes. Based on the techniques in one dimensional bin packing algorithm Super Harmonic by Seiden, we give a framework for online hypercube packing problem and obtain new upper bounds of asymptotic competitive ratios. For square packing, we get an upper bound of 2.1439, which is better

Xin Han; Deshi Ye; Yong Zhou

2006-01-01

124

Well packing system  

Microsoft Academic Search

This patent describes a packing structure and method of packing which can be used in the wellbore of injection wells for the recovery of heavy oils, shale oils, and tars, and in well shafts for in-situ coal gasification. The packing can also be used in the wellbore of gas and light oil production wells. The packing is used to provide

Drnevich

1990-01-01

125

Hydraulics. FOS: Fundamentals of Service.  

ERIC Educational Resources Information Center

|This manual on hydraulics is one of a series of power mechanics texts and visual aids for training in the servicing of agricultural and industrial machinery. Focus is on oil hydraulics. Materials provide basic information and illustrations for use by vocational students and teachers as well as shop servicemen and laymen. The twelve chapters focus…

John Deere Co., Moline, IL.

126

Complex of operations for increasing reliability of hydraulic turbogenerator units of the At-Bashinsk hydroelectric power plant  

Microsoft Academic Search

Vibrational testing conducted on the structure of the room containing the suspension type hydraulic generators is described. Results indicated that a high vibration value (2A-50..mu..) was caused by close coincidence of the frequency of inherent vibrations of the covering of the floor with the frequency of induced vibrations generated by the bearing bases the hydro units - that is, a

V. E. Engel; V. I. Kolen Kolesnikov; A. S. Dolgopolov

1980-01-01

127

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT III, AUTOMATIC TRANSMISSIONS--HYDRAULICS (PART I).  

ERIC Educational Resources Information Center

|THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO INTRODUCE BASIC HYDRAULIC PRINCIPLES AND PROVIDE AN UNDERSTANDING OF HYDRAULIC TRANSMISSIONS USED IN DIESEL POWERED VEHICLES. TOPICS ARE WHY USE HYDRAULICS, REVIEWING BASIC PHYSICS LAWS IN RELATION TO HYDRAULICS, UNDERSTANDING THE HYDRAULIC SYSTEM, AND DEVELOPING A BASIC HYDRAULIC SYSTEM. THE…

Human Engineering Inst., Cleveland, OH.

128

Experience in the ultrasonic testing of fastening studs in the covers of hydraulic units at hydroelectric power plants  

Microsoft Academic Search

The criteria for evaluation of the admissibility of discontinuity flaws under the threads of studs during their inspection\\u000a from the end face without unscrewing them from their seat in a hydraulic unit frame are experimentally substantiated. A transducer\\u000a with the optimal parameters that allows one to reveal cracks of minimal depths is selected. Ultrasonic inspection of studs\\u000a with a hexahedron

V. V. Mikhalev; D. M. Davydov; S. V. Shishkin

2011-01-01

129

Thermal hydraulic calculations to support increase in operating power in McClellen Nuclear Radiation Center(MNRC) TRIGA reactor  

Microsoft Academic Search

The RELAP5\\/Mod3.1 computer program has been used to successfully perform thermal-hydraulic analyses to support the Safety Analysis for increasing the MNRC reactor from 1.0 MW to 2.0 MW. The calculation results show the reactor to have operating margin for both the fuel temperature and critical heat flux limits. The calculated maximum fuel temperature of 705 C is well below the

1998-01-01

130

Hydraulic flywheel  

SciTech Connect

A pair of separable sections forming a hollow structure are coupled to a rotatable shaft. Controlled quantities of hydraulic fluid are introduced into the hollow structure through a passageway within the shaft. One of the sections is selectively slidable along the shaft, for release of fluid from within the structure.

Maxwell, T.J.

1982-06-22

131

Integrated hydraulic system  

SciTech Connect

An integrated hydraulic system is described for a vehicle having a propulsion engine comprising a first fixed capacity or displacement hydraulic pump. A steering mechanism hydraulically operating circuit supplies the hydraulic fluid delivered by the first hydraulic pump into a steering mechanism. It also comprises a second fixed capacity or displacement hydraulic pump. A work implement hydraulically operating circuit selectively supplies the hydraulic fluid delivered by the second hydraulic pump through a pilot operated directional control valve into the steering mechanism hydraulically operating circuit and/or the work implement hydraulically operating circuit.

Karakama, T.

1987-01-06

132

Thermal hydraulic calculations to support increase in operating power in McClellen Nuclear Radiation Center(MNRC) TRIGA reactor.  

SciTech Connect

The RELAP5/Mod3.1 computer program has been used to successfully perform thermal-hydraulic analyses to support the Safety Analysis for increasing the MNRC reactor from 1.0 MW to 2.0 MW. The calculation results show the reactor to have operating margin for both the fuel temperature and critical heat flux limits. The calculated maximum fuel temperature of 705 C is well below the 750 C operating limit. The critical heat flux ratio was calculated to be 2.51.

Jensen, R. T.

1998-05-05

133

Leaf Pack Network  

NSDL National Science Digital Library

The Leaf Pack Network (LPN) is a network of teachers and students investigating their local stream ecosystems by participating in the leaf pack experiment, which involves creating an artificial leaf pack (dry leaves in a mesh bag), immersing it in a stream for 3-4 weeks, and examining it for signs of aquatic insects as indicators of stream health. Participating classrooms share their data through the internet. This activity highlights the connection between streamside forests and the ecology of rivers and streams.

134

Hydraulic Arm Challenge  

NSDL National Science Digital Library

Students design and build a mechanical arm that lifts and moves an empty 12-ounce soda can using hydraulics for power. Small design teams (1-2 students) design and build a single axis for use in the completed mechanical arm. One team designs and builds the grasping hand, another team the lifting arm, and a third team the rotation base. The three design groups must work to communicate effectively through written and verbal communication and sketches.

The Tufts Center For Engineering Educational Outreach

135

On the basically single-type excitation source of resonance in the wind tunnel and in the hydroturbine channel of a hydraulic power plant  

NASA Astrophysics Data System (ADS)

We have investigated the spectra of pressure pulsations in the near field of the open working section of the wind tunnel with a vortex flow behind the tunnel blower formed like the flow behind the hydroturbine of a hydraulic power plant. We have made a comparison between the measurement data for pressure pulsations and the air stream velocity in tunnels of the above type and in tunnels in which a large-scale vortex structure behind the blower is not formed. It has been established that the large-scale vortex formation in the incompressible medium behind the blade system in the wind tunnel is a source of narrow-band acoustic radiation capable of exciting resonance self-oscillations in the tunnel channel.

Karavosov, R. K.; Prozorov, A. G.

2012-01-01

136

Estimation of the hydraulic conductivity of a two-dimensional fracture network using effective medium theory and power-law averaging  

NASA Astrophysics Data System (ADS)

Most oil and gas reservoirs, as well as most potential sites for nuclear waste disposal, are naturally fractured. In these sites, the network of fractures will provide the main path for fluid to flow through the rock mass. In many cases, the fracture density is so high as to make it impractical to model it with a discrete fracture network (DFN) approach. For such rock masses, it would be useful to have recourse to analytical, or semi-analytical, methods to estimate the macroscopic hydraulic conductivity of the fracture network. We have investigated single-phase fluid flow through generated stochastically two-dimensional fracture networks. The centers and orientations of the fractures are uniformly distributed, whereas their lengths follow a lognormal distribution. The aperture of each fracture is correlated with its length, either through direct proportionality, or through a nonlinear relationship. The discrete fracture network flow and transport simulator NAPSAC, developed by Serco (Didcot, UK), is used to establish the “true” macroscopic hydraulic conductivity of the network. We then attempt to match this value by starting with the individual fracture conductances, and using various upscaling methods. Kirkpatrick’s effective medium approximation, which works well for pore networks on a core scale, generally underestimates the conductivity of the fracture networks. We attribute this to the fact that the conductances of individual fracture segments (between adjacent intersections with other fractures) are correlated with each other, whereas Kirkpatrick’s approximation assumes no correlation. The power-law averaging approach proposed by Desbarats for porous media is able to match the numerical value, using power-law exponents that generally lie between 0 (geometric mean) and 1 (harmonic mean). The appropriate exponent can be correlated with statistical parameters that characterize the fracture density.

Zimmerman, R. W.; Leung, C. T.

2009-12-01

137

Career Action Pack.  

ERIC Educational Resources Information Center

One of five McDonald's Action Packs, these instructional materials for ninth and tenth graders (and more able sixth and seventh graders) have incorporated ideas around three career development goals--subject relevance, career awareness, and self-awareness. The action pack contains six units--three units each in the subject areas of language arts…

Blum, Robert E.; Raymond, Carolyn D.

138

Flat Pack Toy Design  

ERIC Educational Resources Information Center

|In this article, the author introduces the concept of flat pack toys. Flat pack toys are designed using a template on a single sheet of letter-sized card stock paper. Before being cut out and built into a three-dimensional toy, they are scanned into the computer and uploaded to a website. With the template accessible from the website, anyone with…

Hutcheson, Brian

2007-01-01

139

Thermal–hydraulics features of the use of LEU U 3Si 2 fuel in low-power reactors  

Microsoft Academic Search

Calculations for the use of the U3Si2 LEU fuel in low-power research reactors were made. The design basis accident was simulated using the feedback coefficients calculated by the BMAC system. Usability of this fuel in low-power research reactors was demonstrated for both normal daily and accidental operation conditions even if the power of the reactor touches 142kW during the design

M. Albarhoum

2010-01-01

140

Search Strategies for Rectangle Packing  

Microsoft Academic Search

Abstract. Rectangle (square) packing problems,involve packing all squares with sizes 1 × 1 to n × n into the minimum area enclosing rectangle (respectively, square). Rectangle packing is a variant of an important problem,in a variety of real-world settings. For example, in electronic design automation, the packing of blocks into a circuit layout is essentially a rectangle packing problem. Rectangle

Helmut Simonis; Barry O’Sullivan

2008-01-01

141

Hydraulic waste energy recovery  

SciTech Connect

Water distribution systems are typically a municipality's largest consumer of energy and greatest expense. The water distribution network has varying pressure requirements due to the age of the pipeline and topographical differences. Certain circumstances require installation of pressure reducing devices in the pipeline to lower the water pressure in the system. The consequence of this action is that the hydraulic energy supplied by the high lift or booster pumps is wasted in the process of reducing the pressure. A possible solution to capture the waste hydraulic energy is to install an in-line electricity generating turbine. Energy recovery using in-line turbine systems is an emerging technology. Due to the lack of technical and other relevant information on in-line turbine system installations, questions of constructability and legal issues over the power service contract have yet to be answered. This study seeks to resolve these questions and document the findings so that other communities may utilize this information. 10 figs.

Lederer, C.C.; Thomas, A.H.; McGuire, J.L. (Detroit Buildings and Safety Engineering Dept., MI (USA))

1990-12-01

142

Design and Testing of Piezoelectric-Hydraulic Actuators.  

National Technical Information Service (NTIS)

This paper describes design methodologies for construction of an actuator that uses smart materials to provide hydraulic fluid power. In the class of actuators described, hydraulic fluid decouples the operating frequency of the output cylinder from the dr...

E. H. Anderson J. E. Lindler M. E. Regelbrugge

2003-01-01

143

46 CFR 112.50-3 - Hydraulic starting.  

Code of Federal Regulations, 2012 CFR

...OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-3 Hydraulic starting. A hydraulic starting system must meet the...

2012-10-01

144

Low energy consumption hydraulic techniques  

NASA Astrophysics Data System (ADS)

This report documents the efforts to develop and test low energy consumption hydraulic techniques. Included is a discussion of the efforts to select and analyze a baseline hydraulic system (Phase 1) and conduct trade studies on various candidate design approaches which could reduce weight and power consumption (Phase 2). In addition, the report discusses the development of a test plan (Phase 3) and the results of an endurance test (Phase 4). This program was directed at 8000 psi hydraulic system technology using a nonflammable hydraulic fluid chlorotrifluoroethylene (CTFE) although the concepts developed could be applied to any fluid at any system pressure. The concepts selected for test were variable system pressure, flow augmentation with load recovery valves and overlapped main valves.

Greene, J. B.; Jeffrey, J. R.; Lohe, S. N.; Pehowski, S. E.; Pierce, N. J.

1988-08-01

145

Graphitic packing removal tool  

DOEpatents

Graphitic packing removal tools are described for removal of the seal rings in one piece from valves and pumps. The packing removal tool has a cylindrical base ring the same size as the packing ring with a surface finish, perforations, knurling or threads for adhesion to the seal ring. Elongated leg shanks are mounted axially along the circumferential center. A slit or slits permit insertion around shafts. A removal tool follower stabilizes the upper portion of the legs to allow a spanner wrench to be used for insertion and removal.

Meyers, K.E.; Kolsun, G.J.

1996-12-31

146

Hydraulic fracturing-1  

SciTech Connect

This book contains papers on hydraulic fracturing. Topics covered include: An overview of recent advances in hydraulic fracturing technology; Containment of massive hydraulic fracture; and Fracturing with a high-strength proppant.

Not Available

1990-01-01

147

Fireproof Brake Hydraulic System.  

National Technical Information Service (NTIS)

The feasibility of a fireproof two-fluid brake hydraulic system which utilizes nonflammable chlorotrifluoroethylene (CTFE) fluid in a dead ended brake hydraulic system mechanically isolated from the primary MIL-H-5606 hydraulic system was studied. Experim...

S. M. Warren J. R. Kilner

1981-01-01

148

Nasal packing and stenting  

PubMed Central

Nasal packs are indispensable in ENT practice. This study reviews current indications, effectiveness and risks of nasal packs and stents. In endoscopic surgery, nasal packs should always have smooth surfaces to minimize mucosal damage, improve wound healing and increase patient comfort. Functional endoscopic endonasal sinus surgery allows the use of modern nasal packs, since pressure is no longer required. So called hemostatic/resorbable materials are a first step in this direction. However, they may lead to adhesions and foreign body reactions in mucosal membranes. Simple occlusion is an effective method for creating a moist milieu for improved wound healing and avoiding dryness. Stenting of the frontal sinus is recommended if surgery fails to produce a wide, physiologically shaped drainage path that is sufficiently covered by intact tissue.

Weber, Rainer K.

2011-01-01

149

Fully Dynamic Bin Packing  

NASA Astrophysics Data System (ADS)

Classic bin packing seeks to pack a given set of items of possibly varying sizes into a minimum number of identical sized bins. A number of approximation algorithms have been proposed for this NP-hard problem for both the on-line and off-line cases. In this chapter we discuss fully dynamic bin packing, where items may arrive (Insert) and depart (Delete) dynamically. In accordance with standard practice for fully dynamic algorithms, it is assumed that the packing may be arbitrarily rearranged to accommodate arriving and departing items. The goal is to maintain an approximately optimal solution of provably high quality in a total amount of time comparable to that used by an off-line algorithm delivering a solution of the same quality.

Ivkovi?, Zoran; Lloyd, Errol L.

150

Towards Human Friendly Hydraulics - Passive Teleoperation of Hydraulic Equipment using a Force Feedback Joystick  

Microsoft Academic Search

Hydraulic systems, as power source and transmission, of- fer many advantages over electromechanical or purely me- chanical counterparts in terms of power density, flexibil- ity and portability. Many hydraulic systems require touch- ing and contacting the physical environments; and many of these systems are directly controlled by human. If hy- draulic systems are passive, they would be safer to interact

Perry Y. Li; Kailash Krishnaswamy

2002-01-01

151

Tiber winding pack design  

Microsoft Academic Search

A preliminary winding pack design was performed with the goal of showing feasibility of producing 10-T maximum field with a pack current density of 40 sq mm while accepting 2.7 kW per coil nuclear heating. A cable-in-conduit conductor design (CIC), reported at the 6th Topical Meeting on the Technology of Fusion Energy, was based on several key issues.

J. R. Miller

1985-01-01

152

Minimal Energy Polymer Packings  

NASA Astrophysics Data System (ADS)

We examine the structure and dynamics of collapsed polymers using a variety of simulation and theoretical techniques. For flexible chains of N ``sticky'' tangent hard spheres, at small N, the ground states are the same as for the nonpolymeric case (NPC) [1], while at large N the ground states are crystallites with close-packed cores. The polymeric nature of the packings gives rise to distinguishable ground-state structures whose multiplicity relative to the NPC grows rapidly with N. We explicitly enumerate the polymer packings for small N and study the most likely packings for large N. We explore the extent to which the packing types and probabilities change with several important properties of the polymer, including the softness of the interaction potential, bending stiffness, bond length, and heterogeneity of the monomers. Typically, small variations of these properties break the degeneracy of NPC ground states, while large variations produce qualitatively different ground-state packings. We also characterize the slow dynamics of transitions between low-energy states at finite temperature. [4pt] [1] N. Arkus, V. N. Manoharan, and M. P. Brenner, PRL, 103, 118303 (2009).

Hoy, Robert

2010-03-01

153

Water hydraulic actuators for ITER maintenance devices  

Microsoft Academic Search

The characteristic advantages of hydraulics (high power density, simple construction and reliability) together with the characteristics of water as the pressure medium (fire and environmentally safe, chemically neutral, not activated nor affected by radiation) are highlighted in critical applications such as remote handling operations in international thermonuclear experimental reactor (ITER). However, lack of commercial selection of water hydraulic components, common

Mikko Siuko; M. Pitkäaho; A. Raneda; J. Poutanen; J. Tammisto; J. Palmer; M. Vilenius

2003-01-01

154

Investigation into Hydraulic Gear Pump Efficiencies during the First Few Hours of the Pumps' Lives and a Comparative Study of Accelerated Life Test Methods on Hydraulic Fluid Power Gear Pumps. Parts 1 and 2.  

National Technical Information Service (NTIS)

This interim report summarizes the results obtained in evaluating the changes in overall efficiency of 18 hydraulic gear pumps during the first few hours of the pumps' lives, that is, during the break-in period. A literature search and a mail survey of in...

1979-01-01

155

Hydraulic oil well pumping apparatus  

SciTech Connect

The preferred embodiment is directed to an oil well pumping apparatus incorporating a walking beam having a horsehead at one end which connects to the sucker rods in the oil well. The opposite end of the walking beam is supported on a fixed pivot. A hydraulic and pneumatic combination unit connects from a supporting platform to a central point on the beam to raise and lower the beam. The improved apparatus utilizes air pressure to balance the static load on the apparatus and dynamically strokes the sucker rod string by imparting a reciprocating motion through hydraulic power applied at a specified rate to raise and lower the walking beam. A pump and motor system for a closed hydraulic loop is included. Alternate preferred embodiments are disclosed. In one form, a lubricating system is incorporated. First and second alternate forms of pickoff apparatus which powers the pneumatically balanced pumping apparatus is also included.

McDuffie, T.F.

1983-09-27

156

Modeling of a novel 3-way rotary type electro-hydraulic valve  

Microsoft Academic Search

Hydraulic actuation is characterized by fast dynamics, high power density, high stiffness, large output force\\/torque, and in recent years it has become an increasing attractive form of robot actuation. Hydraulic control valves that not only provide the interface between hydraulic power element and actuators, but also receive feedback signal and adjust the system output accordingly, are key components of hydraulic

Yousheng Yang; Emanuele Guglielmino; Jian S. Dai; Thiago Boaventura; Darwin G. Caldwell

2010-01-01

157

A numerical modeling approach for assessment of progressive caving of strata and performance of hydraulic powered support in longwall workings  

Microsoft Academic Search

A numerical modeling approach is proposed for predicting the progressive caving behaviour of strata and performance of powered roof support in a given geo-mining and strata condition. The study suggests that face convergence slope of 75mm\\/m of face advance may be considered as the maximum permissible value for selection of optimal capacity support for safe working in a given strata

G. S. P. Singh; U. K. Singh

2009-01-01

158

The use of MIL-PRF-87257 hydraulic fluid as a switching medium for a high-power microwave switch  

Microsoft Academic Search

Gigawatt-class repetitive pulsed power applications require reliable, heavy-duty closing switches. Coupled with the requirement for pulse lengths on the order of a microsecond or less for many of these applications, engineers have typically used switch technologies that allow current to flow by inducing an arc (or arcs) in a pressurized, gaseous medium. Alternatively, a flowing, high-pressure liquid dielectric that can

Stephen L. Gunderson; George W. Fultz; Steven Patton

2012-01-01

159

Densest binary sphere packings.  

PubMed

The densest binary sphere packings in the ?-x plane of small to large sphere radius ratio ? and small sphere relative concentration x have historically been very difficult to determine. Previous research had led to the prediction that these packings were composed of a few known "alloy" phases including, for example, the AlB(2) (hexagonal ?), HgBr(2), and AuTe(2) structures, and to XY(n) structures composed of close-packed large spheres with small spheres (in a number ratio of n to 1) in the interstices, e.g., the NaCl packing for n=1. However, utilizing an implementation of the Torquato-Jiao sphere-packing algorithm [Torquato and Jiao, Phys. Rev. E 82, 061302 (2010)], we have discovered that many more structures appear in the densest packings. For example, while all previously known densest structures were composed of spheres in small to large number ratios of one to one, two to one, and very recently three to one, we have identified densest structures with number ratios of seven to three and five to two. In a recent work [Hopkins et al., Phys. Rev. Lett. 107, 125501 (2011)], we summarized these findings. In this work, we present the structures of the densest-known packings and provide details about their characteristics. Our findings demonstrate that a broad array of different densest mechanically stable structures consisting of only two types of components can form without any consideration of attractive or anisotropic interactions. In addition, the structures that we have identified may correspond to currently unidentified stable phases of certain binary atomic and molecular systems, particularly at high temperatures and pressures. PMID:22463175

Hopkins, Adam B; Stillinger, Frank H; Torquato, Salvatore

2012-02-22

160

Online Square and Cube Packing  

Microsoft Academic Search

In online square packing, squares of dieren t sizes arrive online and need to be packed into unit squares which are called bins. The goal is to minimize the number of bins used. Online cube packing is dened analogously. We show an upper bound of 2:2697 and a lower bound of 1:6406 for online square packing, and an upper bound

Leah Epstein; Rob van Stee

161

Hydraulic controls of summer Arctic pack ice albedo  

Microsoft Academic Search

Linkages between albedo, surface morphology, melt pond distribution, and properties of first-year and multiyear sea ice have been studied at two field sites in the North American Arctic between 1998 and 2001. It is shown that summer sea-ice albedo depends critically on surface melt-pond hydrology, controlled by melt rate, ice permeability, and topography. Remarkable short-term and interannual variability in pond

H. Eicken; T. C. Grenfell; D. K. Perovich; J. A. Richter-Menge; K. Frey

2004-01-01

162

New Bounds for Multi-Dimensional Packing.  

National Technical Information Service (NTIS)

New upper and lower bounds are presented for a multi-dimensional generalization of bin packing called box packing. Several variants of this problem, including bounded space box packing, square packing, variable sized box packing and resource augmented box...

R. Van Stee S. Seiden

2001-01-01

163

Optimal configuration design for hydraulic split hybrid vehicles  

Microsoft Academic Search

Hydraulic hybrid vehicles are more suitable for heavy-duty applications in urban driving than hybrid electric vehicles because of the high power density and low cost of hydraulic devices. However, the low rotational speeds of hydraulic pump\\/motor and the low energy density of the accumulator impose severe constraints on the design and control for these vehicles. The split configuration is an

Chiao-Ting Li; Huei Peng

2010-01-01

164

On the dynamics of hydraulic lines supplying servosystems  

Microsoft Academic Search

Measures for achieving an almost quiescent state of hydraulic power supply pressure are outlined. Models for hydraulic pipelines supplying hydraulic control systems, which integrate dynamic behavior of the pipelines, the pressure control valve, or pressure controlled variable displacement pump, gas accumulators, and Helmholtz resonators are developed. Experiments show that pressure fluctuations due to pump flow pulsations are suppressed by a

A. A. Ham

1982-01-01

165

Packed Input Vector Simulation with the Inversion Algorithm  

Microsoft Academic Search

The Inversion Algorithm is an event driven algorithm whose performance meets or exceeds that of traditional compiled-code simulators. However, existing implementations of the algorithm do not allow several vectors to be packed into a single word, thus limiting the power of the algorithm. Because the Inversion Algorithm does not represent net values in the conventional way, the simple packing techniques

William J. Schilp; Peter M. Maurer

166

Moving Learning Action Pack.  

ERIC Educational Resources Information Center

One of five McDonald's Action Packs, this teacher's guide and activity sheets describe an early childhood-level program that introduces basic movement and guides students and teachers into the process of learning through moving. Basic movement skills necessary for sports and games, gymnastics, and dance are developed through eight themes, each…

American Alliance for Health, Physical Education, and Recreation, Washington, DC.

167

Bubbles ClassPack  

NSDL National Science Digital Library

Using More Picture-Perfect Science Lessons: Using Children's Books to Guide Inquiry, K-4 in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatche

2010-04-22

168

Downhole steam packing  

Microsoft Academic Search

A steam or thermal packer for use in subterranean wells having an integral expansion joint is disclosed. The packer has a multi-component, nonresilient, nonenergizing packing element, as well as a multi-component, nonenergizing, nonresilient sealing element engaging the expansion joint. Energy is stored in elements of the packer housing and in the dynamic seal assembly to maintain the sealing integrity establishing

Luke

1985-01-01

169

DIY Fraction Pack.  

ERIC Educational Resources Information Center

|Describes a very successful attempt to teach fractions to year 5 pupils based on pupils making their own fraction pack. Children decided for themselves how to make the fractional slices used in the activity using colored cardboard sheets and templates of a paper circle consisting of 24 equal slices. (Author/NB)|

Graham, Alan; Graham, Louise

2003-01-01

170

Earthlets ClassPack  

NSDL National Science Digital Library

Using Picture-Perfect Science Lessons in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatched time-saver and a great deal. This Cla

2010-04-20

171

MICROBIAL TRANSPORT THROUGH POROUS MEDIA: THE EFFECTS OF HYDRAULIC CONDUCTIVITY AND INJECTION VELOCITY  

EPA Science Inventory

The effects of hydraulic conductivity and injection on microbial transport through porous media were investigated. lass chromatography columns were packed separately with clean quartz sand of two diameters (0.368 mm or 0.240 mm) and two hydraulic conductivities (1.37 x 10-1 cm/se...

172

Commercial utility frequency AC to high frequency AC soft switching power conversion circuit with non smoothing DC link for IH dual packs heater  

Microsoft Academic Search

In this paper, a novel topology of soft switching PWM high frequency AC power conversion conditioning and processing circuit without DC smoothing capacitor filter link from the voltage grid of utility frequency AC power supply source with 60 Hz-100 V or 60 Hz-200 V is proposed and introduced for innovative consumer induction heating (IH) boiler applications as a hot water

Hisayuki Sugimura; Tarek Ahmed; Mohamed Orabi; Hyun-Woo Lee; Mutsuo Nakaoka

2004-01-01

173

CT appearance of omental packs  

Microsoft Academic Search

Liver lacerations may be surgically treated by using the omentum as packing. A radiologist can differentiate potential postoperative complications, such as abscess, hematoma, and biloma, from these packs on computed tomographic scans by noting attenuation values.

R. J. Sefczek; A. R. Lupetin; I. Beckman; N. Dash

1985-01-01

174

Online square and cube packing  

Microsoft Academic Search

Abstract In online square packing, squares of dieren t sizes arrive online and need to be packed into unit squares which are called bins. The goal is to minimize the number of bins used. Online cube packing is dened,analogously. We show an upper bound of 2:2697 and a lower bound of 1:6406 for online square packing, and an upper bound

Leah Epstein; Rob Van Stee

2005-01-01

175

Flooding characteristics of Goodloe packing  

Microsoft Academic Search

Experimental flooding data for the countercurrent flow of air and water in a 7.62-cm-diam glass column filled with Goodloe packing were compared with a correlation reported by the packing manufacturer. Flooding rates observed in this study were as low as one-half those predicted by the correlation. Rearranging the packing by inverting the column and removing some packing segments yielded results

J. M. Begovich; J. S. Watson

1976-01-01

176

In-well hydraulics of the electromagnetic borehole flowmeter  

Microsoft Academic Search

Previous studies have suggested that head losses associated with the application of the electromagnetic borehole flowmeter (EBF) can have important and detrimental effects on the use of the instrument for measurement of hydraulic conductivity (K) profiles. Head losses associated with flow through the meter may cause bypass flow around the packer if the well is gravel packed. In any type

Cynthia L. Dinwiddie; Nicole A. Foley; Fred J. Molz

1999-01-01

177

Packing-limited growth  

Microsoft Academic Search

We consider growing spheres seeded by random injection in time and space.\\u000aGrowth stops when two spheres meet leading eventually to a jammed state. We\\u000astudy the statistics of growth limited by packing theoretically in d dimensions\\u000aand via simulation in d=2, 3, and 4. We show how a broad class of such models\\u000aexhibit distributions of sphere radii with

Peter Sheridan Dodds; Joshua S. Weitz

2002-01-01

178

Downhole steam packing  

SciTech Connect

A steam or thermal packer for use in subterranean wells having an integral expansion joint is disclosed. The packer has a multi-component, nonresilient, nonenergizing packing element, as well as a multi-component, nonenergizing, nonresilient sealing element engaging the expansion joint. Energy is stored in elements of the packer housing and in the dynamic seal assembly to maintain the sealing integrity establishing by the nonresilient sealing elements.

Luke, M. A.

1985-10-22

179

Gravel packs require planning  

SciTech Connect

Every year the petroleum industry spends millions of dollars cleaning sand out of oil and gas wells in addition to repairing pumps, chokes, valves, and other eroded equipment. Additional millions of dollars have been lost by restricted production rates. In this first of a two-part series, the authors present an overview of incompetent sands and recommend specific requirements for gravel pack and slurry pack systems. Because sand control in oil and gas wells is expensive, corrective treatment must be measured against three related criteria: stop movement and production of sand; maintain maximum well productivity; and payout treatment costs within reasonable time. All these criteria must be met for a sand control treatment to be truly successful, and each must be considered when designing, performing, and evaluating a sand control treatment. Research efforts in recent years have been aimed at complete stoppage of formation sand movement while retaining maximum fluid productivity. Minimizing formation damage (e.g., from completion fluids, perforations, gravel-sand mixing, and plugged screens) has aided in achieving higher production rates from gravel-packed wells.

Sparlin, D.D.; Hagen, R.W.

1985-08-05

180

Calibrating hydraulic network models  

Microsoft Academic Search

Although calibration should always be included in any hydraulic analysis, it is often neglected or done haphazardly. As a result, inappropriate data may be used or data errors may be overlooked, so the resulting hydraulic model is of limited value. The novice may see calibrating a hydraulic network model as a task as daunting as climbing Mt. Everest. This article

Lindell E. Ormsbee; Srinivasa Lingireddy

1997-01-01

181

Thermal-hydraulic analysis of an annular fuel element: The Achilles' heel of the particle bed reactor  

NASA Astrophysics Data System (ADS)

The low pressure nuclear thermal propulsion (LPNTP) concept offers significant improvements in rocket engine specific impulse over rockets employment chemical propulsion. This study investigated a parametric thermal-hydraulic analysis of an annular fueld element, also referred to as a fuel pipe, using the computer code ATHENA (Advanced Thermal Hydraulic Energy Network Analyzer). The fuelpipe is an annular particle bed fuel element of the reactor with radially inward flow of hydrogen through the element. In this study, the outlet temperature of the hydrogen is parametrically related to key effects, including the reactor power at two different pressure drops, the effect of power coupling for in-core testing, and the effect of hydrogen flow rates. Results show that the temperature is linearly related to the reactor power, but not to pressure drop, and that cross flow inside the fuelpipe occurs at approximately 0.3 percent of the radial flow rates. More importantly, because of limited properties data for hydrogen and the probable yet uncharacterized dynamic distribution of packed fuel particles in the fuel pin during reactor operations, results from any thermal-hydraulic code, including ATHENA, do not give designs of satisfactory fidelity. This lack of design confidence is the Achilles' heel for current LPNTP reactors.

Dibben, Mark J.; Tuttle, Ronald F.

1993-01-01

182

Effect of the initial gas maldistribution on the pressure drop of structured packings  

Microsoft Academic Search

This paper presents results of a large-scale experimental study devoted to establishing the relation between the quality of initial gas (mal)distribution, as created by common liquid collecting devices used in redistribution sections of packed columns, and the hydraulics of a structured packing bed. Both dry and wet bed experiments were conducted with air–water system under ambient conditions, using a 1.4m

Ž Oluji?; A Mohamed Ali; P. J Jansens

2004-01-01

183

Solder joint reliability of high I\\/O ceramic-ball-grid arrays and ceramic quad-flat packs in computer environments: The PowerPC 603TM and PowerPC 604TM microprocessors  

Microsoft Academic Search

Recent trends in wafer fabrication techniques have produced devices with smaller feature dimensions, increasing gate count and increased chip I\\/Os. This trend has placed increased emphasis on microelectronic packaging. Surface-mountable packages such as the ceramic quad-flat-pack (CQFP) have provided solutions for many high I\\/O package issues. As the I\\/O count increases, the pitch has been driven down to the point

D. Gerke; G. Kromann; A. Srikantappa

1998-01-01

184

Solder joint reliability of high I\\/O ceramic-ball-grid arrays and ceramic quad-flat-packs in computer environments: the PowerPC 603TM and PowerPC 604TM microprocessors  

Microsoft Academic Search

Recent trends in wafer fabrication techniques have produced devices with smaller feature dimensions, increasing gate count and chip inputs\\/outputs (I\\/Os). This trend has placed increased emphasis on microelectronics packaging. Surface-mountable packages such as the ceramic quad-flat-pack (CQFP) have provided solutions for many high I\\/O package issues. As the I\\/O count gets higher, the pitch has been driven smaller to the

R. David Gerke; Gary B. Kromann

1999-01-01

185

Safety and efficiency conflicts in hydraulic architecture: scaling from tissues to trees.  

PubMed

Tree hydraulic architecture exhibits patterns that propagate from tissue to tree scales. A challenge is to make sense of these patterns in terms of trade-offs and adaptations. The universal trend for conduits per area to decrease with increasing conduit diameter below the theoretical packing limit may reflect the compromise between maximizing the area for conduction versus mechanical support and storage. Variation in conduit diameter may have two complementary influences: one being compromises between efficiency and safety and the other being that conduit tapering within a tree maximizes conductance per growth investment. Area-preserving branching may be a mechanical constraint, preventing otherwise more efficient top-heavy trees. In combination, these trends beget another: trees have more, narrower conduits moving from trunks to terminal branches. This pattern: (1) increases the efficiency of tree water conduction; (2) minimizes (but does not eliminate) any hydraulic limitation on the productivity or tissue growth with tree height; and (3) is consistent with the scaling of tree conductance and sap flow with size. We find no hydraulic reason why tree height should scale with a basal diameter to the two-thirds power as recently claimed; it is probably another mechanical constraint as originally proposed. The buffering effect of capacitance on the magnitude of transpiration-induced xylem tension appears to be coupled to cavitation resistance, possibly alleviating safety versus efficiency trade-offs. PMID:18088335

Sperry, John S; Meinzer, Frederick C; McCulloh, Katherine A

2007-12-10

186

Multiple fixed hydraulic geometry turbine control system  

Microsoft Academic Search

A plurality of selected fixed hydraulic geometry turbine generators are programmed for operation at rated efficiencies by interrupting flow to the turbines under control of a programmable power controller receiving water level, flow and power monitoring inputs. The turbines selected are of discreet sizes simultaneously operative only under maximum flow conditions of the hydropower source, and otherwise operated in accordance

1984-01-01

187

Hydraulic fracture design optimization  

SciTech Connect

This research and development investigation, sponsored by US DOE and the oil and gas industry, extends previously developed hydraulic fracture geometry models and applied energy related characteristic time concepts towards the optimal design and control of hydraulic fracture geometries. The primary objective of this program is to develop rational criteria, by examining the associated energy rate components during the hydraulic fracture evolution, for the formulation of stimulation treatment design along with real-time fracture configuration interpretation and control.

Lee, Tae-Soo; Advani, S.H.

1992-01-01

188

Hydraulic fracture design optimization  

SciTech Connect

This research and development investigation, sponsored by US DOE and the oil and gas industry, extends previously developed hydraulic fracture geometry models and applied energy related characteristic time concepts towards the optimal design and control of hydraulic fracture geometries. The primary objective of this program is to develop rational criteria, by examining the associated energy rate components during the hydraulic fracture evolution, for the formulation of stimulation treatment design along with real-time fracture configuration interpretation and control.

Lee, Tae-Soo; Advani, S.H.

1992-06-01

189

Characteristics of a rotating packed bed equipped with blade packings  

Microsoft Academic Search

This study examined pressure drop and mass transfer of a rotating packed bed (RPB) equipped with blade packings using stripping of oxygen from water and absorption of isopropyl alcohol from gas. As to pressure drop, the gas flow rate appeared to be a more important factor than the liquid flow rate due to less liquid holdup under centrifugal field. For

Chia-Chang Lin; Guo-Shing Jian

2007-01-01

190

MICROBIAL TRANSPORT THROUGH POROUS MEDIA; THE EFFECTS OF HYDRAULIC CONDUCTIVITY AND INJECTION VELOCITY. (R825513C019)  

EPA Science Inventory

The effects of hydraulic conductivity and injection velocity on microbial transport through porous media were investigated. Glass chromatography columns were packed separately with clean quartz sand of two diameters (0.368mm or 0.24O mm) and two hydraulic conductivities (1.37&...

191

Electrically recharged battery employing a packed/spouted bed metal particle electrode  

DOEpatents

A secondary metal air cell, employing a spouted/packed metal particle bed and an air electrode, is described. More specifically a zinc air cell well suited for use in electric vehicles which is capable of being either electrically or hydraulically recharged. 5 figs.

Siu, S.C.; Evans, J.W.; Salas-Morales, J.

1995-08-15

192

3 HPLC columns and packings  

Microsoft Academic Search

In this chapter on HPLC columns, we are discussing both the surface chemistry of a packing as well as column design and performance. In the section that covers column chemistry, we cover modern options of base materials as well as the commonly used approaches towards the surface chemistry of a packing. Specific subsections are dedicated to the selectivity of reversed-phase

Uwe D. Neue; Bonnie A. Alden; Edward R. Grover; Eric S. Grumbach; Pamela C. Iraneta; Alberto Méndez

2007-01-01

193

Bin Packing with Rejection Revisited  

Microsoft Academic Search

We consider the following generalization of bin packing. Each item is associated with a size bounded by 1, as well as a rejection cost, that an algorithm must pay if it chooses not to pack this item. The cost of an algorithm is the sum of all rejection costs of rejected items plus the number of unit sized bins used

Leah Epstein

2006-01-01

194

Valve Stem and Packing Assembly.  

National Technical Information Service (NTIS)

A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by mean...

J. J. Wordin

1990-01-01

195

Valve stem and packing assembly.  

National Technical Information Service (NTIS)

A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by mean...

J. J. Wordin

1990-01-01

196

Computer simulations of particle packing.  

National Technical Information Service (NTIS)

Computer code has been developed to rapidly simulate the random packing of disks and spheres in two and three dimensions. Any size distribution may be packed. The code simulates varying degrees of inter particle conditions ranging from sticky to free flow...

J. Cesarano M. J. McEuen T. Swiler

1996-01-01

197

Method for gravel packing wells  

SciTech Connect

This patent describes a method for gravel packing a perforated well which penetrates a formation or reservoir. It comprises placing into a solution a shear-thickening composition in an amount sufficient to form a carrier fluid having a viscosity sufficient to suspend gravel packing sand therein for a time sufficient to pack the well; adding gravel packing sand into the fluid thereby suspending the sand therein; injecting the carrier fluid and sand mixture into the well under conditions sufficient to cause the mixture to shear thicken so as to provide for transportation of the sand to perforations in the well without spreading from the mixture; and directing the mixture into the perforations which diminishes shear forces acting on the mixture thereby causing a reduction in viscosity of the carrier fluid, sand separation from the fluid, improved fluid leak-off into the formation, and uniform gravel packing of the perforations.

Yeh, C.S.

1991-12-31

198

Bud development and hydraulics  

PubMed Central

The distal zone of one-year-old apple (Malus domestica) shoots was studied on five cultivars for bud size and composition (number of appendages) and hydraulic conductance before bud burst. Our hypothesis was that bud development was related to hydraulic conductance of the sap pathway to the bud independent of an acrotonic (proximal vs. distal) effect. Bud size and composition, and hydraulic conductance, were highly variable for all cultivars. A positive correlation was demonstrated between both the number of cataphylls and green-leaf primordia and hydraulic conductance. Cultivar and bud size affected the intercept of these relationships more than the slope suggesting similar scaling between these variables but different hydraulic efficiencies. A great proportion of small buds were also characterized by null values of hydraulic conductance. Our study suggests that hydraulically mediated competitions exist between adjacent buds within a same branching zone prefiguring the variability of lateral types in the following growing season. It is hypothesized that this developmental patterning is driven by hydraulic characteristics of the whole-metamer, including the subtending leaf, during bud development.

Cochard, Herve

2008-01-01

199

Hydraulics of pipelines  

Microsoft Academic Search

This text\\/reference addresses all hydraulic aspects of pipeline design. Incorporates many real-life examples from the author's experience in the design and operation of pipelines. Topics covered include basic equations necessary to pipeline design, how to conduct a feasibility study and perform economic analysis, design considerations for pumps and valves, how to suppress cavitation, hydraulic transients, trapped air, and methods of

Tullis

1989-01-01

200

Downhole hydraulic seismic generator  

DOEpatents

A downhole hydraulic seismic generator system for transmitting energy wave vibrations into earth strata surrounding a borehole. The system contains an elongated, unitary housing operably connected to a well head aboveground by support and electrical cabling, and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a hydraulic oscillator containing a double-actuating piston whose movement is controlled by an electro-servovalve regulating a high pressure hydraulic fluid flow into and out of upper and lower chambers surrounding the piston. The spent hydraulic fluid from the hydraulic oscillator is stored and pumped back into the system to provide high pressure fluid for conducting another run at the same, or a different location within the borehole.

Gregory, Danny L. (Corrales, NM); Hardee, Harry C. (Albuquerque, NM); Smallwood, David O. (Albuquerque, NM)

1992-01-01

201

Downhole hydraulic seismic generator  

DOEpatents

A downhole hydraulic seismic generator system for transmitting energy wave vibrations into earth strata surrounding a borehole. The system contains an elongated, unitary housing operably connected to a well head aboveground by support and electrical cabling, and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a hydraulic oscillator containing a double-actuating piston whose movement is controlled by an electro-servovalve regulating a high pressure hydraulic fluid flow into and out of upper and lower chambers surrounding the piston. The spent hydraulic fluid from the hydraulic oscillator is stored and pumped back into the system to provide high pressure fluid for conducting another run at the same, or a different location within the borehole. 4 figs.

Gregory, D.L.; Hardee, H.C.; Smallwood, D.O.

1990-12-31

202

Downhole hydraulic seismic generator  

DOEpatents

A downhole hydraulic seismic generator system for transmitting energy wave vibrations into earth strata surrounding a borehole. The system contains an elongated, unitary housing operably connected to a well head aboveground by support and electrical cabling, and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a hydraulic oscillator containing a double-actuating piston whose movement is controlled by an electro-servovalve regulating a high pressure hydraulic fluid flow into and out of upper and lower chambers surrounding the piston. The spent hydraulic fluid from the hydraulic oscillator is stored and pumped back into the system to provide high pressure fluid for conducting another run at the same, or a different location within the borehole. 4 figs.

Gregory, D.L.; Hardee, H.C.; Smallwood, D.O.

1990-01-01

203

Packed Bed Reactor Technology for Chemical-Looping Combustion  

Microsoft Academic Search

Chemical-looping combustion (CLC) has emerged as an alternative for conventional power production processes to intrinsically integrate power production and CO2 capture. In this work a new reactor concept for CLC is proposed, based on dynamically operated packed bed reactors. With analytical expressions validated with a more detailed numerical model, it is demonstrated that a constant, very high temperature air stream

Sander Noorman; Sint Annaland van Martin; Hans Kuipers; N. A. M. Asbroek; P. H. M. Feron

2007-01-01

204

Distillation Columns with Structured Packings in the Next Decade  

Microsoft Academic Search

The analysis of the history of structured packings allows the conclusion that the inno- vation cycle will become faster. Based on the separation power as an alternative way to represent the performance characteristics an estimate of the next level of what might be the ultimative separa- tion power is given. Regarding the column internals like distributors only slight improvements are

Lothar Spiegel; Werner Meier

2003-01-01

205

Nasal septal packing: which one?  

PubMed

The aim of this study was to investigate the effects of four different types of nasal packs on pain, nasal fullness and postoperative bleeding following septoplasty. Prospective randomised double blind study was conducted. The study group included 119 patients who underwent endonasal septoplasty under general anaesthesia. Four types of nasal packing materials were utilized: (1) Merocel standard 8-cm nasal dressing without airway, (2) Doyle Combo splint (DCS), (3) Merocel in a glove finger and (4) Vaseline gauze. All packs were removed at the 48th hour (±3 h) after the surgery. Three different variables were investigated following the surgical procedure: (1) pain, (2) nasal fullness and (3) bleeding after removal of the nasal packing material. DCS produced the greatest pain at the first and sixth postoperative hours. At the first postoperative day, the greatest pain score was reported for Merocel in the glove finger and the least for Merocel. The pain scores during the removal of the nasal packings were highest for Merocel and lowest for Merocel in the glove finger. DCS had the lowest nasal fullness score. Bleeding ratio was highest for Merocel, followed by Vaseline gauze, DCS and Merocel in the glove finger. Many different commercially available packing materials are presently used, each with inherent advantages and disadvantages. We evaluated the pain, nasal fullness and bleeding potential of four nasal packing materials and determined that Merocel had the highest pain potential during removal and the highest rate of bleeding following removal. PMID:22160143

Ac?o?lu, Engin; Edizer, Deniz Tuna; Yi?it, Özgür; Onur, F?rat; Alkan, Zeynep

2011-12-09

206

Random Packing and Random Covering Sequences.  

National Technical Information Service (NTIS)

In a sequential packing problem, random objects are uniformly and independently selected from some space. A selected object is either packed or rejected, depending on the distance between it and the nearest object which has been previously packed. A satur...

C. D. Sutton

1988-01-01

207

7 CFR 51.3055 - Standard pack.  

Code of Federal Regulations, 2013 CFR

... United States Standards for Florida Avocados Standard Pack § 51.3055 Standard pack. (a) The avocados shall be packed in accordance with...fruit in the container. Size of the avocados may be specified by count....

2013-01-01

208

PackBot: a versatile platform for military robotics  

NASA Astrophysics Data System (ADS)

The iRobot PackBot is a combat-tested, man-portable UGV that has been deployed in Afghanistan and Iraq. The PackBot is also a versatile platform for mobile robotics research and development that supports a wide range of payloads suitable for many different mission types. In this paper, we describe four R&D projects that developed experimental payloads and software using the PackBot platform. CHARS was a rapid development project to develop a chemical/radiation sensor for the PackBot. We developed the CHARS payload in six weeks and deployed it to Iraq to search for chemical and nuclear weapons. Griffon was a research project to develop a flying PackBot that combined the capabilities of a UGV and a UAV. We developed a Griffon prototype equipped with a steerable parafoil and gasoline-powered motor, and we completed successful flight tests including remote-controlled launch, ascent, cruising, descent, and landing. Valkyrie is an ongoing research and development project to develop a PackBot payload that will assist medics in retrieving casualties from the battlefield. Wayfarer is an applied research project to develop autonomous urban navigation capabilities for the PackBot using laser, stereo vision, GPS, and INS sensors.

Yamauchi, Brian M.

2004-09-01

209

Water vs. oil hydraulic actuation for a robot leg  

Microsoft Academic Search

The significant competitive advantage of hydraulics (high power density, large output force\\/torque and wide range of speeds) together with the properties of water (low compressibility, high thermal conductivity, low solubility of air, non-flammability and no environmental hazard) make water hydraulic actuation very suitable for systems such as legged robots. This paper addresses the comparison between a water and an oil

Yousheng Yang; Claudio Semini; Emanuele Guglielmino; Nikos G. Tsagarakis; Darwin G. Caldwell

2009-01-01

210

Hydraulic Pressure Intensifiers for Use by Working Divers.  

National Technical Information Service (NTIS)

The need for a reliable high pressure (10,000 psi) source of hydraulic power for use by divers has led to the evaluation and modification of two commercially available hydraulic pressure intensifiers, The operation of the internal mechanism of the intensi...

A. M. Parisi R. L. Brackett

1974-01-01

211

46 CFR 58.30-10 - Hydraulic fluid.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Hydraulic fluid. 58.30-10 Section 58.30-10...AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-10 Hydraulic fluid. (a) The requirements of this...

2009-10-01

212

Some thermal hydraulic challenges in sodium cooled fast reactors  

Microsoft Academic Search

Sodium cooled fast reactors have been developed in France for nearly 50 years with successively Rapsodie, Phenix and Superphenix plants. Thermal hydraulic challenges have progressively increased with the power and the size of the reactors. After Superphenix stop in 1997, the thermal hydraulic activity on sodium cooled fast reactors was drastically reduced for about 10 years. Nowadays, the so-called Astrid

D. Tenchine

2010-01-01

213

A 6DOF vibration isolation system for hydraulic hybrid vehicles  

Microsoft Academic Search

This paper presents the results of vibration isolation analysis for the pump\\/motor component of hydraulic hybrid vehicles (HHVs). The HHVs are designed to combine gasoline\\/diesel engine and hydraulic power in order to improve the fuel efficiency and reduce the pollution. Electric hybrid technology is being applied to passenger cars with small and medium engines to improve the fuel economy. However,

Mohammad Elahinia; Walter W. Olson; Paul Fontaine

2006-01-01

214

Method for packing chromatographic beds  

DOEpatents

Column chromatography beds are packed through the application of static force. A slurry of the chromatography bed material and a non-viscous liquid is filled into the column plugged at one end, and allowed to settle. The column is transferred to a centrifuge, and centrifuged for a brief period of time to achieve a predetermined packing level, at a range generally of 100-5,000 gravities. Thereafter, the plug is removed, other fixtures may be secured, and the liquid is allowed to flow out through the bed. This results in an evenly packed bed, with no channeling or preferential flow characteristics.

Freeman, David H. (Potomac, MD); Angeles, Rosalie M. (Germantown, MD); Keller, Suzanne (Rockville, MD)

1991-01-01

215

Hydraulic fracturing method employing special sand control technique  

SciTech Connect

A subsurface oil or gas reservoir is hydraulically fractured by injecting a fracturing fluid through perforations in the casing of a well penetrating into such subsurface reservoir. The fracturing fluid contains a clay stabilizing agent for stabilizing clay particles or fines along the face of the resulting formation fracture. A proppant comprising a gravel packing sand is injected into the fracture. Oil or gas is then produced from the reservoir through the fracture into the well.

Stowe, L. R.; Strubbar, M. K.

1985-10-29

216

Bin Packing with Rejection Revisited  

Microsoft Academic Search

We consider the following generalization of bin packing. Each item has a size in (0,1] associated with it, as well as a rejection\\u000a cost, that an algorithm must pay if it chooses not to pack this item. The cost of an algorithm is the sum of all rejection\\u000a costs of rejected items plus the number of unit sized bins used

Leah Epstein

2010-01-01

217

Packing nanomechanics of viral genomes  

Microsoft Academic Search

.  We investigate the osmotic equilibrium between a bulk polyethylene glycol (PEG) solution and DNA tightly packed in a spherical\\u000a capsid. We base our analysis on the equations of thermodynamic equilibrium in terms of osmotic pressure. The equality between\\u000a external osmotic pressure of PEG and osmotic pressure of tightly packed DNA gives us the DNA encapsidation curves. In this\\u000a way we

A. Šiber; M. Dragar; V. A. Parsegian; R. Podgornik

2008-01-01

218

On packing R-trees  

Microsoft Academic Search

We propose new R-tree packing techniques for static databases. Given a collection of rectangles, we sort them and build the R-tree bottom-up. There are several ways to sort the rectangles; the innovation of this work is the use of fractals, and specifically the hilbert curve, to achieve better ordering of the rectangles and eventually better pack- ing. We proposed and

Ibrahim Kamel; Christos Faloutsos

1993-01-01

219

IOSDL Seasoar Hydraulic Unit.  

National Technical Information Service (NTIS)

A series of static and dynamic laboratory measurements taken on five IOSDL (Institute of Oceanographic Sciences Deacon Laboratory) SeaSoar hydraulic units is reported. Their operation, the test equipment and the test methods used are described. Analysis o...

T. J. P. Gwilliam D. Grohmann R. F. Wallace

1992-01-01

220

Investigations of Hydraulic Turbines.  

National Technical Information Service (NTIS)

Contents: Effects of the initial degree of turbulence on the hydrodynamic coefficients of the blade systems of axial hydraulic turbines; Accuracy of determining the flow around straight blade cascades; Application of Stanitz and Prian's approximate theory...

G. A. Svinarev

1969-01-01

221

Hydraulic System Acoustical Diagnostics.  

National Technical Information Service (NTIS)

This project is a continuation of previous acoustics studies conducted to determine if the vibration signature of hydraulic components could provide information concerning the operational health of the system. The concept of using internally produced nois...

R. Inoue R. K. King

1980-01-01

222

The crack tip region in hydraulic fracturing  

Microsoft Academic Search

We present analytical tip region solutions for fracture width and pressure when a power law fluid drives a plane strain fracture in an impermeable linear elastic solid. Our main result is an intermediate asymptotic solution in which the tip region stress is dominated by a singularity which is particular to the hydraulic fracturing problem. Moreover this singularity is weaker than

J. Desroches; E. Detournay; B. Lenoach; P. Papanastasiou; J. R. A. Pearson; M. Thiercelin; A. Cheng

1994-01-01

223

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT IX, AUTOMATIC TRANSMISSIONS--HYDRAULIC SYSTEM (PART I).  

ERIC Educational Resources Information Center

|THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OIL FLOW WITHIN HYDRAULIC TRANSMISSIONS USED ON DIESEL POWERED VEHICLES. TOPICS ARE GENERAL DESCRIPTION, HYDRAULIC CIRCUITS, AND BRAKE HYDRAULIC CIRCUIT AND OPERATION. THE MODULE CONSISTS OF A SELF-INSTRUCTIONAL PROGRAMED TRAINING FILM "LEARNING ABOUT THE ALLISON…

Human Engineering Inst., Cleveland, OH.

224

Device for Automatic Balancing of Hydraulic Jib Crane.  

National Technical Information Service (NTIS)

A device for automatic equilibration of the hydraulic jib crane consisting of mobile counterbalance, subject to the change of load, run by power hydrocylinder connected with cylinder-transducers, placed on the operating devices that determine load and ret...

L. D. Fabachnikov Y. K. Bugoslavskii

1967-01-01

225

Shore Effect Model, Atlantic Generating Station; Hydraulic Model Investigation.  

National Technical Information Service (NTIS)

A distorted-scale hydraulic model investigation was performed to determine the potential effect, if any, of a proposed offshore nuclear power plant on shoreline evolution. Model measurements of current patterns with and without the breakwater were directl...

D. D. Davidson J. H. Barwis R. D. Carver R. W. Whalin

1975-01-01

226

Paediatric oncology information pack for general practitioners  

PubMed Central

An information pack covering important aspects of paediatric oncology has been developed for general practitioners. Sixty general practitioners who received the information pack found that it helped them in managing children with neoplastic disease and their families. The pack has also improved communications between the oncology unit and general practitioners. Similar packs could be produced by paediatricians working in other specialties.

James, J A; Harris, D J; Mott, M G; Oakhill, A

1988-01-01

227

Particle packing simulations based on Newtonian mechanics  

Microsoft Academic Search

A program to simulate the packing of round particles was made in the course of this work. The theoretical packing of the particles was studied in 3-dimensional situations with the program. The effects of friction, elasticity, size and spring co-efficient on packing were examined. It was observed that increased friction caused decreased packing density. Elasticity had a minor effect on

Simo Siiriä; Jouko Yliruusi

2007-01-01

228

Pumping plant fly wheel hydraulic surge protector  

Microsoft Academic Search

Hydraulic surge protection is provided in a pumping plant by providing a synchronous motor\\/generator connected across the electrical power bus lines used to energize the motor operated pumps for pumping liquid through a pipeline. A fly wheel is provided on the synchronous motor\\/generator having an inertia to maintain the motor\\/generator operating in the event of an electrical power failure between

1979-01-01

229

Simulation study on hydraulic control system of high-speed transplanter with SIMSAE  

Microsoft Academic Search

The hydraulic control system model of the high-speed rice transplanter is constructed and simulated with SIMSAE sorftware. The actual working condition of the power-assisted steering and hydraulic copying shape are simulated to improve the stability and high efficiency of the designed hydraulic system. The hydraulic control system has been used in practice with one type high-speed rice transplanter. After a

Weiguo Zhu; Qian Zhao; Xiaoming Hu

2012-01-01

230

Hydraulic dredging, a sediment removal technique  

SciTech Connect

Sediment was successfully removed from a Peabody Coal Company pond near Macon, Missouri, by a Mud Cat Model SP-810 hydraulic dredge. Previous attempts using land-based equipment had been unsatisfactory. The hydraulic-powered auger and submerged pump easily removed 882 m/sup 3/ (1154 yd/sup 3/) and pumped the slurry a distance of 305 m (1000 ft) to a disposal area. The hydraulic dredge was more effective and cheaper to operate than land-based equipment. The dredge cost was $1.31/m/sup 3/ ($1.00/yd/sup 3/), the dragline cost was $6.54/m/sup 3/ ($5.00/yd/sup 3/) and the front-end loader cost was $15.70/m/sup 3/ ($12.00/yd/sup 3/), under optimum conditions.

Spotts, J.W.

1980-12-01

231

A Hydraulic Model Study of Intake Structure  

SciTech Connect

In the intake structure of a nuclear power plant, undesirable pump operating characteristics such as vortices and nonuniform pump-approach flow around the pump bells take place frequently due to poorly arranged intake geometry. Therefore, prior to the construction or renovation of intake structure or internal auxiliary facilities, a hydraulic modeling test should be performed to predict the undesirable hydraulic phenomena. In this study, a three-dimensional turbulence model was applied for a numerical modeling test, and a 1:10 scale, geometrically undistorted physical model was employed to investigate the hydraulic behavior and simulate pump operating conditions in the intake structure of Kori Nuclear Units 3 and 4 in Korea. The results from these numerical and physical model tests were compared, and an antivortex device was also proposed to ensure a stable suction condition of the pumps.

Kim, Jin Won [Korea Electric Power Research Institute (Korea, Republic of); Lee, Dae Soo [Korea Electric Power Research Institute (Korea, Republic of); Kim, Jong Hyun [Electric Power Research Institute (Korea, Republic of)

2001-04-15

232

Critical Behavior in Packings of Soft Disks  

NASA Astrophysics Data System (ADS)

Using molecular dynamics simulations of packings of soft disks, we show that there appears to be a critical point at T=0 and ?c near close-packing. The pressure P behaves as an order parameter for a transition between a state where no particles interact (P=0) to a state where many particles interact (P>0). At any nonzero temperature, P is always nonzero. We find that the pressure vanishes at the critical density as a power law in |?-?_c| at T=0 (consistent with earlier studies on athermal models), and as a power law in T at ? ? phi_c. We also define a susceptibility based on mean-square fluctuations in the pressure and show that it appears to diverge as T arrow 0 and ? arrow ?_c. In addition, we find that this susceptibility exhibits finite size effects, suggesting that there is a correlation length that grows as the critical point is approached. We argue that this critical point plays an essential role in the glass transitions of liquids and colloids and the jamming of granular materials and suspensions.

O'Hern, Corey; Langer, Stephen; Liu, Andrea; Nagel, Sidney

2001-03-01

233

VOCs absorption in rotating packed beds equipped with blade packings  

Microsoft Academic Search

This work investigated the volatile organic compounds (VOCs) removal efficiency of the RPB equipped with blade packings using absorption. Methanol, methyl ethyl ketone and methyl acetate were used as the model VOCs herein. The VOCs removal efficiency (E) was observed to increase with the rotational speed and the liquid flow rate but decrease with the gas flow rate. Moreover, methanol

Chia-Chang Lin; Yu-Chiao Lin; Kuo-Shin Chien

2009-01-01

234

TU Delft: Hydraulic Engineering  

NSDL National Science Digital Library

Given the Dutch reputation for water management, it's no surprise that one of their leading technical institutes, The Technische Universiteit Delft, offers a program in Hydraulic Engineering. The website, in both Dutch and English, describes their program as an attempt "to bridge the gap between basic sciences (fluid mechanics and soil mechanics in particular) and practical engineering applications in the design, construction, maintenance, management and eventually the demolition of hydraulic structures." The Education section of the website posts MSc theses completed by their students. The research section describes current and recently completed research projects and includes a listing of publications, some of which are available to download. The website also has a link to a Hydraulic Engineering portal, which offers various publication databases (some in Dutch only), and the Civil Engineering Knowledge Centre, which provides library access and discussion forums for students and staff of Civil Engineering.

235

What Is Hydraulic Fracturing?  

NSDL National Science Digital Library

Hydraulic fracturing is a process used in nine out of 10 natural gas wells in the United States, where millions of gallons of water, sand and chemicals are pumped underground to break apart the rock and release the gas. Scientists are worried that the chemicals used in fracturing may pose a threat either underground or when waste fluids are handled and sometimes spilled on the surface. This poster presentation illustrates the under surface process of hydraulic fracking and the distribution flow to the market.

2012-01-01

236

Design of steam-stripping columns for removal of volatile organic compounds from water using random and structured packings  

SciTech Connect

Mass-transfer data at different feed and steam rates, using structured and random packings, have been collected to develop a model for the design or analysis of packed columns for stripping of volatile organic compounds (VOCs) from water. The steam-stripping experiments were conducted in a stainless steel column of 0.245-m internal diameter, with 2.8 m of packed section. The packings used were Sulzer BX gauze structured packing, Mellapak 250Y structured packing, 1-in. Flexirings, and 1-in. Fleximax random packing. The VOCs were chloroform (CH{sub 3}Cl) and toluene (C{sub 7}H{sub 8}). The model considers the simultaneous occurrence of mass transfer and hydraulic phenomena with the same expressions for liquid and vapor mass-transfer coefficients and the same expression for effective interfacial area with one constant for each packing. The average deviation for the measured and calculated volumetric mass-transfer coefficient and effective height of packing is 0.29 and 0.23, respectively.

Castillo, J.R.O.D.; Guerrero-Medina, G.; Lopez-Toledo, J.; Rocha, J.A.

2000-03-01

237

Reduction of hydraulic conductivity in column simulations of unconsolidated sediments by growth of in situ microflora  

Microsoft Academic Search

Laboratory experiments were employed to determine the effects of microbial growth upon the hydraulic conductivity (K) of unconsolidated sediments at Kelly Air Force Base, Texas. Indigenous microflora were isolated from sediment samples collected at sites contaminated with toxic organic compounds (e.g. dichlorobenzene) by plating on concentrated and dilute media. Plexiglas columns were packed with silica beads or Kelly AFB sediment

F. P. Bertetti; S. J. Birnbaum

1992-01-01

238

Decrease of the hydraulic conductivity of sand columns by Methanosarcina barkeri  

Microsoft Academic Search

The extent to which a methanogen can clog sand columns was examined: two permeameters packed with clean quartz sand were sterilized, saturated with water, inoculated with Methanosarcina barkeri and percolated under upward flow conditions. After approx. 5 months, the hydraulic conductivity of the sand had decreased to 3% and 25% of the highest values measured earlier. At that point, gas-filled

D. Sanchez de Lozada; P. Vandevivere; P. Baveye; S. Zinder

1994-01-01

239

Packing Schemes for Gang Scheduling  

Microsoft Academic Search

. Jobs that do not require all processors in the system can bepacked together for gang scheduling. We examine accounting traces fromseveral parallel computers to show that indeed many jobs have small sizesand can be packed together. We then formulate a number of such packingalgorithms, and evaluate their effectiveness using simulations based onour workload study. The results are that two

Dror G. Feitelson

1996-01-01

240

Grand Canyon ClassPack  

NSDL National Science Digital Library

Using Picture-Perfect Science Lessons in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatched time-saver and a great deal. This Cla

2010-04-22

241

Fractal Beauty of Bin Packing.  

National Technical Information Service (NTIS)

In the variable-sized online bin packing problem, one has to assign items to bins one by one. The bins are drawn from some fixed set of sizes, and the goal is to minimize the sum of the sizes of the bins used. We present the first unbounded space algorith...

L. Epstein R. Van Stee S. Seiden

2001-01-01

242

Imaginative Inventions ClassPack  

NSDL National Science Digital Library

Using More Picture-Perfect Science Lessons: Using Children's Books to Guide Inquiry, K-4 in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatche

2010-04-25

243

What's Poppin'? ClassPack  

NSDL National Science Digital Library

Using Picture-Perfect Science Lessons in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatched time-saver and a great deal. This Cla

2010-04-19

244

Loco Beans ClassPack  

NSDL National Science Digital Library

Using More Picture-Perfect Science Lessons: Using Children's Books to Guide Inquiry, K-4 in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatche

2010-04-22

245

GRASP for set packing problems  

Microsoft Academic Search

The principles of the Greedy Randomized Adaptative Search Procedure (GRASP) metaheuristic are instantiated for the set packing problem. We investigated several construction phases, and evaluated improvements based on advanced strategies. These improvements include a self-tuning procedure (using reactive GRASP), an intensification procedure (using path relinking) and a procedure involving the diversification of the selection (using a learning process). Two sets

Xavier Delorme; Xavier Gandibleux; Joaquin Rodriguez

2004-01-01

246

Laboratory Determination of Hydraulic Conductivity  

NSDL National Science Digital Library

From D.B. McWhorterand D. K. Sunda's 1977 Ground-Water Hydrology and Hydraulics, this two page excerpt outlines and details Laboratory Determination of Hydraulic Conductivity. Here, visitors will find illustrations and formula to understand the concept.

2008-02-07

247

Development of Lightweight Hydraulic Supports.  

National Technical Information Service (NTIS)

After evaluating preceding studies and designs of lightweight supports, the all-hydraulic and the hydromechanical concepts were selected for detailed design and fabrication. Further analysis and testing showed that the all-hydraulic design was economicall...

P. T. Alexander

1982-01-01

248

In-well hydraulics of the electromagnetic borehole flowmeter  

SciTech Connect

Previous studies have suggested that head losses associated with the application of the electromagnetic borehole flowmeter (EBF) can have important and detrimental effects on the use of the instrument for measurement of hydraulic conductivity (K) profiles. Head losses associated with flow through the meter may cause bypass flow around the packer if the well is gravel packed. In any type of well, changing head losses with meter position can cause changes in flow into the well that are not related directly to the K distribution. Such flow changes, or redistribution, can cause errors in the calculation of the K profile. Numerical simulations, based on measured head losses, indicate that bypass flow in gravel packed systems increases with increasing flow rate through the meter, increasing gravel pack conductivity, and increasing gravel pack thickness. Ideally, the EBF should not be used in gravel packed wells, due to the occurrence of bypass flow. Investigations into the flow redistribution phenomenon indicate that the top portion of the aquifer is where the greatest over-estimation of K occurs. The portion of the well below the flowmeter is isolated from the observed drawdown as measured from the surface. In this region, the well experiences a reduced drawdown, which differs from the observed drawdown by an amount equal to the head loss at that meter position. Flow redistribution causes a more pronounced effect in more highly conductive mediums and may be almost negligible in mediums of low conductivity.

Dinwiddie, C.L.; Foley, N.A.; Molz, F.J. [Clemson Univ., Anderson, SC (United States). Dept. of Environmental Engineering and Science

1999-03-01

249

Determining the Porosity and Saturated Hydraulic Conductivity of Binary Mixtures  

SciTech Connect

Gravels and coarse sands make up significant portions of some environmentally important sediments, while the hydraulic properties of the sediments are typically obtained in the laboratory using only the fine fraction (e.g., <2 mm or 4.75 mm). Researchers have found that the content of gravel has significant impacts on the hydraulic properties of the bulk soils. Laboratory experiments were conducted to measure the porosity and the saturated hydraulic conductivity of binary mixtures with different fractions of coarse and fine components. We proposed a mixing-coefficient model to estimate the porosity and a power-averaging method to determine the effective particle diameter and further to predict the saturated hydraulic conductivity of binary mixtures. The proposed methods could well estimate the porosity and saturated hydraulic conductivity of the binary mixtures for the full range of gravel contents and was successfully applied to two data sets in the literature.

Zhang, Z. F.; Ward, Anderson L.; Keller, Jason M.

2009-09-27

250

Determining the Porosity and Saturated Hydraulic Conductivity of Binary Mixtures  

SciTech Connect

Gravels and coarse sands make up significant portions of some environmentally important sediments, while the hydraulic properties of the sediments are typically obtained in the laboratory using only the fine fraction (e.g., <2 mm or 4.75 mm). Researchers have found that the content of gravel has significant impacts on the hydraulic properties of the bulk soils. Laboratory experiments were conducted to measure the porosity and the saturated hydraulic conductivity of binary mixtures with different fractions of coarse and fine components. We proposed a mixing-coefficient model to estimate the porosity and a power-averaging method to determine the effective particle diameter and further to predict the saturated hydraulic conductivity of binary mixtures. The proposed methods could well estimate the porosity and saturated hydraulic conductivity of the binary mixtures for the full range of gravel contents and was successfully applied to two data sets in the literature.

Zhang, Z. F.; Ward, Anderson L.; Keller, Jason M.

2011-02-14

251

Packing of Elastic Wires in Spherical Cavities  

NASA Astrophysics Data System (ADS)

We investigate the morphologies and maximum packing density of thin wires packed into spherical cavities. Using simulations and experiments, we find that ordered as well as disordered structures emerge, depending on the amount of internal torsion. We find that the highest packing densities are achieved in low torsion packings for large systems, but in high torsion packings for small systems. An analysis of both situations is given in terms of energetics and comparison is made to analytical models of DNA packing in viral capsids.

Stoop, N.; Najafi, J.; Wittel, F. K.; Habibi, M.; Herrmann, H. J.

2011-05-01

252

46 CFR 28.880 - Hydraulic equipment.  

Code of Federal Regulations, 2010 CFR

...Hydraulic equipment. (a) Each hydraulic system must be so designed and installed...operating pressure. (c) Each hydraulic system must be equipped with at least... (d) All material in a hydraulic system must be suitable for use...

2009-10-01

253

46 CFR 28.405 - Hydraulic equipment.  

Code of Federal Regulations, 2010 CFR

...Hydraulic equipment. (a) Each hydraulic system must be so designed and installed...operating pressure. (c) Each hydraulic system must be equipped with at least... (d) All material in a hydraulic system must be suitable for use...

2009-10-01

254

46 CFR 28.880 - Hydraulic equipment.  

Code of Federal Regulations, 2010 CFR

...Hydraulic equipment. (a) Each hydraulic system must be so designed and installed...operating pressure. (c) Each hydraulic system must be equipped with at least... (d) All material in a hydraulic system must be suitable for use...

2010-10-01

255

Bridges in three-dimensional granular packings: Experiments and simulations  

NASA Astrophysics Data System (ADS)

In this letter, we present the first experimental study of bridge structures in three-dimensional dry granular packings. When bridges are small, they are predominantly “linear”, and have an exponential size distribution. Larger, predominantly “complex” bridges, are confirmed to follow a power-law size distribution. Our experiments, which use X-ray tomography, are in good agreement with the simulations presented here, for the distribution of sizes, end-to-end lengths, base extensions and orientations of predominantly linear bridges. Quantitative differences between the present experiment and earlier simulations suggest that packing fraction is an important determinant of bridge structure.

Cao, Y. X.; Chakrabortty, B.; Barker, G. C.; Mehta, A.; Wang, Y. J.

2013-04-01

256

Hydraulic type starting clutch  

Microsoft Academic Search

This patent describes a hydraulic type starting clutch comprising: an input shaft; an input rotating member arranged for rotation in unison with the input shaft; an output shaft; an output rotating member arranged for rotation in unison with the output shaft; friction plates interposed between the input rotating member and the output rotating member for engagement to transmit torque from

K. Ohzono; K. Hayashi; M. Saito; M. Kato; Y. Yoshida

1987-01-01

257

Water Treatment Technology - Hydraulics.  

ERIC Educational Resources Information Center

|One of twelve water treatment technology units, this student manual on hydraulics provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: head loss in pipes in series, function loss in…

Ross-Harrington, Melinda; Kincaid, G. David

258

Integration in Hydraulics.  

ERIC Educational Resources Information Center

|This paper presents an application of integration to the field of hydraulics. An integral relation for the time required to drop the fluid contained in a cylindrical tank from one level to another using a hole in the tank wall is derived. Procedures for constructing the experimental equipment and procedures for determining the coefficient of…

Sworder, Steven C.

259

Hydraulic fracturing process  

Microsoft Academic Search

A process is described for hydraulically fracturing a permeable subterranean formation in which the fracture faces are treated to reduce their permeability to the fracturing fluid. Propping agent is placed in the fracture in a conventional manner whereby the bulk of the propping agent is deposited in the fracture at a location remote from the well. Thereafter the fracture faces

Pye

1973-01-01

260

Hydraulic fracturing propping agent  

SciTech Connect

A high strength propping agent for use in hydraulic fracturing of subterranean formations comprising solid, spherical particles having an alumina content of between 40 and 60%, a density of less than 3.0 gm/cc and an ambient temperature permeability of 100,000 or more millidarcies at 10,000 psi.

Lunghofer, E. P.

1985-06-11

261

Hydraulic fracturing technique  

Microsoft Academic Search

This improved hydraulic fracturing method consists of injecting into previously formed fractures filled with a very viscous fluid, a relatively nonviscous fluid containing sand or other propping agent material. The low viscosity fluid fingers through the high viscosity fluid in radial channels and when the fingers containing the propping agent reach the extremity of the highly viscous fluid, they mushroom

1965-01-01

262

Hydraulic fracturing propping agent  

Microsoft Academic Search

A high strength propping agent for use in hydraulic fracturing of subterranean formations comprising solid, spherical particles having an alumina content of between 40 and 60%, a density of less than 3.0 gm\\/cc and an ambient temperature permeability of 100,000 or more millidarcies at 10,000 psi.

Lunghofer

1985-01-01

263

Hydraulic-Powered Fan Coil for Advanced Hydronic Distribution Systems, Part I: Thermal Performance and Energy Characterization of Conventional Fan Coil Units  

Microsoft Academic Search

This paper reports the testing of two conventional fan-coil units of different size in a controlled environment rig to deter- mine their thermal performance and energy requirements during cooling operation. Part II of this paper describes replacing the fan motor with a small water turbine as the power source to modify the same two units. The thermal performance and energy

Evelyn Baskin; Edward A. Vineyard; Essam A. Ibrahim

264

Design under Uncertainty and Assessment of Performance Reliability of a Dual-Use Medium Truck with Hydraulic-Hybrid Powertrain and Fuel Cell Auxiliary Power Unit  

Microsoft Academic Search

Medium trucks constitute a large market segment of the commercial transportation sector, and are also used widely for military tactical operations. Recent technological advances in hybrid powertrains and fuel cell auxiliary power units have enabled design alternatives that can improve fuel economy and reduce emissions dramatically. However, deterministic design optimization of these configurations may yield designs that are optimal with

Michael Kokkolaras; Zissimos Mourelatos; Loucas Louca; Zoran Filipi; George Delagrammatikas; Anna Stefanopoulou; Panos Papalambros; Dennis Assanis

265

Hydraulic charcterization of carbonatic rock  

Microsoft Academic Search

The hydraulic conductivity, K(theta), and the water retention, theta(h), are needed to predict the flow of water and solute transport in unsaturated porous media. During recent decades methods have been developed to determine these hydraulic properties for rock. We have developed a methodology, based on Wind's evaporation method for soils, to measure in the laboratory the water retention and hydraulic

M. C. Caputo; A. Basile; R. de Mascellis; J. R. Nimmo; M. Vurro; N. Walsh

2003-01-01

266

75: Determining Soil Hydraulic Properties  

Microsoft Academic Search

Hydraulic properties are required for modeling water and solute transport in unsaturated soils. The bottleneck for the successful application of numerical simulation models lays usually in their parameter estimation requirements. Methods to determine hydraulic properties can be classified into indirect and direct approaches. Indirect methods encompass the estimation of hydraulic properties by pedotransfer functions from more easily measured soil properties,

WOLFGANG DURNER; KAI LIPSIUS

2005-01-01

267

Computer simulation of hydraulic fractures  

Microsoft Academic Search

We provide a brief historical background of the development of hydraulic fracturing models for use in the petroleum and other industries. We discuss scaling laws and the propagation regimes that control the growth of hydraulic fractures from the laboratory to the field scale. We introduce the mathematical equations and boundary conditions that govern the hydraulic fracturing process, and discuss numerical

J. Adachi; E. Siebrits; A. Peirce; J. Desroches

2007-01-01

268

Generation of Random Particle Packings for Discrete Element Models  

NASA Astrophysics Data System (ADS)

An important step in the setup process of Discrete Element Model (DEM) simulations is the generation of a suitable particle packing. There are quite a number of properties such a granular material specimen should ideally have, such as high coordination number, isotropy, the ability to fill arbitrary bounding volumes and the absence of locked-in stresses. An algorithm which is able to produce specimens fulfilling these requirements is the insertion based sphere packing algorithm originally proposed by Place and Mora, 2001 [2] and extended in this work. The algorithm works in two stages. First a number of "seed" spheres are inserted into the bounding volume. In the second stage the gaps between the "seed" spheres are filled by inserting new spheres in a way so they have D+1 (i.e. 3 in 2D, 4 in 3D) touching contacts with either other spheres or the boundaries of the enclosing volume. Here we present an implementation of the algorithm and a systematic statistical analysis of the generated sphere packings. The analysis of the particle radius distribution shows that they follow a power-law with an exponent ? D (i.e. ?3 for a 3D packing and ?2 for 2D). Although the algorithm intrinsically guarantees coordination numbers of at least 4 in 3D and 3 in 2D, the coordination numbers realized in the generated packings can be significantly higher, reaching beyond 50 if the range of particle radii is sufficiently large. Even for relatively small ranges of particle sizes (e.g. Rmin = 0.5Rmax) the maximum coordination number may exceed 10. The degree of isotropy of the generated sphere packing is also analysed in both 2D and 3D, by measuring the distribution of orientations of vectors joining the centres of adjacent particles. If the range of particle sizes is small, the packing algorithm yields moderate anisotropy approaching that expected for a face-centred cubic packing of equal-sized particles. However, once Rmin < 0.3Rmax a very high degree of isotropy is demonstrated in both 2D and 3D. The analysis demonstrates that this space-filling packing algorithm fulfills many of the requirements required to produce granular material specimens for DEM simulations. These include a high coordination number, isotropy and the absence of lock-in stresses. The algorithm has been implemented as a module (called gengeo[1]) for the Python[3] scripting language and provides the capacity to fill arbitrary bounding volumes or combinations of bounding volumes. The main disadvantage of this space-filling packing approach is the inability to specify a priori the particle size distribution of the final specimen.

Abe, S.; Weatherley, D.; Ayton, T.

2012-04-01

269

Biotreatment of phenol-contaminated wastewater in a spiral packed-bed bioreactor  

Microsoft Academic Search

A spiral packed-bed bioreactor inoculated with microorganisms obtained from activated sludge was used to conduct a feasibility\\u000a study for phenol removal. The reactor was operated continuously at various phenol loadings ranging from 53 to 201.4 g m?3 h?1, and at different hydraulic retention times (HRT) in the range of 20–180 min to estimate the performance of the device. The\\u000a results indicated that phenol removal

Chi-Wen Lin; Chia-Hsien Yen; Shen-Long Tsai

2009-01-01

270

The application of hydraulics in the 2,000 kW wind turbine generator  

Microsoft Academic Search

A 2000 kW turbine generator using hydraulic power in two of its control systems is being built under the management of NASA Lewis Research Center. The hydraulic systems providing the control torques and forces for the yaw and blade pitch control systems are discussed. The yaw-drive-system hydraulic supply provides the power for positioning the nacelle so that the rotary axis

S. Onufreiczuk

1978-01-01

271

THEORETICAL ANALYSIS AND EXPERIMENTAL VERIFICATION OF A MONOPROPELLANT DRIVEN FREE PISTON HYDRAULIC PUMP  

Microsoft Academic Search

The authors present a novel free piston hydraulic pump (FPHP) to supply hydraulic power to mobile robotic systems. The basic design incorporates several innovative features. Monopropellant fuel (e.g. hydrogen peroxide) decomposes into high temperature gases when exposed to a solid catalyst. The hot gases drive a novel engine\\/pump that produces high-pressure hydraulic flow to power actuators. The elimination of fuel\\/oxidizer

Timothy G. McGee; Justin W. Raade; Homayoon Kazerooni

272

7 CFR 984.15 - Pack.  

Code of Federal Regulations, 2013 CFR

...AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts. [73 FR 11337, Mar....

2013-01-01

273

Packing in Two and Three Dimensions.  

National Technical Information Service (NTIS)

This dissertation investigates Multidimensional Packing Problems (MD- PPs): the Pallet Loading Problem (PLP), the Multidimensional Knapsack Problem (MD-KP), and the Multidimensional Bin Packing Problem (MD-BPP). In these problems, there is a set of items,...

G. H. Martins

2003-01-01

274

Random Close Packings of Regular Polygons  

NASA Astrophysics Data System (ADS)

We study by numerical simulation the progressive densification of assemblies of equal regular polygons (pentagons and heptagons). We follow the evolution of the packing fraction, of the coordination numbers and of the void space structure during the densification. At high packing fraction (Csim 0.83), ordered zones appear. This can be compared with what occurs in equal disc assemblies in which a Random Close Packing limit exists for a packing fraction Csim 0.83 above which some local order is present.

Limon Duparcmeur, Y.; Troadec, J. P.; Gervois, A.

1997-10-01

275

Thawing of cook-freeze catering packs  

Microsoft Academic Search

Centralised catering facilities using frozen and chilled food in bulk packs require dedicated thawing systems for the frozen supplies. Data on thawing times for foods in such packs are essential for correct design and operation of these systems. The current study initially used computer modelling to identify the fastest and slowest thawing packs from a typical hospital catering range. Estimated

Tim Brown; Judith A. Evans; Christian James; Stephen J. James; M. Veronica L. Swain

2006-01-01

276

7 CFR 51.1217 - Standard pack.  

Code of Federal Regulations, 2013 CFR

...e) Peaches packed in boxes equipped with cell compartments or molded trays shall be of the proper size for the cells or the molds in which they are packed. (f) Peaches placed in individual paper cups and packed in boxes shall be in cups of the...

2013-01-01

277

Gas flow distribution in packed columns  

Microsoft Academic Search

The distribution of gas flow over the cross section of packed columns depends on the manner of gas flow feeding, on packing type, packing arrangement, and internal devices in the apparatus body. Various types of gas inlet devices are studied in order to estimate their ability for creation of uniform velocity profiles. The gas flow uniformity is characterized by the

Rumen Darakchiev; Chavdar Dodev

2002-01-01

278

Computational Modelling of Particle Packing in Concrete  

Microsoft Academic Search

Physical particle packing is becoming a hot topic in concrete technology as more and more types of granular materials are used in concrete either for ecological or for engineering purposes. Although various analytical methods have been developed for optimum mixture design, comprehensive information on particle packing properties is still missing, e.g. on the impact of the packing method on such

H. He

2010-01-01

279

Hydraulic manipulator research at ORNL  

SciTech Connect

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

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

1997-03-01

280

Method for packing chromatographic beds  

SciTech Connect

This patent describes process for packing column chromatography beds. It comprises preparing a slurry of chromatographic bed material and a liquid comprising at least one of water, methanol, chloroform and hexane, the bed material being denser than the liquid, introducing the slurry into a column provided with a removable plug at one end and allowing the slurry to settle in the column such that the bed material falls to the plugged end, thereafter centrifuging the column under the condition that the surface of the liquid is at all points and times above the surface of the bed material, with respect to the plugged end, and continuing the centrifuging for a period of time to obtain a predetermined packing level in the bed material in the substantial absence of channeling, removing the plug from the column and allowing the liquid to drain through the bed and out of the column.

Freeman, D.H.; Angeles, R.M.; Keller, S.

1991-01-15

281

Evaluation of the thermal-hydraulic response and fuel rod thermal and mechanical deformation behavior during the power burst facility test LOC-3. [PWR  

SciTech Connect

An evaluation of the results from the LOC-3 nuclear blowdown test conducted in the Power Burst Facility is presented. The test objective was to examine fuel and cladding behavior during a postulated cold leg break accident in a pressurized water reactor (PWR). Separate effects of rod internal pressure and the degree of irradiation were investigated in the four-rod test. Extensive cladding deformation (ballooning) and failure occurred during blowdown. The deformation of the low and high pressure rods was similar; however, the previously irradiated test rod deformed to a greater extent than a similar fresh rod exposed to identical system conditions.

Yackle, T.R.; MacDonald, P.E.; Broughton, J.M.

1980-01-01

282

Calculation of hydraulic friction losses in dc motors filled with liquid dielectric  

Microsoft Academic Search

Hydraulic friction during rotation of the armature in a dc motor filled with liquid dielectric is a major source of power loss, up to 40% of all power losses in such a motor. These losses are usually reduced by impregnating the end turns of armature coils with a compound and smoothing their outside surfaces. Hydraulic losses are best determined experimentally

V. P. Morozkin

1984-01-01

283

Local anisotropy in globally isotropic granular packings.  

PubMed

We report on two-dimensional computer simulations of frictionless granular packings at various area fractions ? above the jamming point ?(c). We measure the anisotropy in coarse-grained stress ?(s) and shear modulus ?(m) as functions of coarse-graining scale, R. ?(s) can be collapsed onto a master curve after rescaling R by a characteristic length scale ? and ?(s) by an anisotropy magnitude A. Both A and ? accelerate as ???(c) from above, consistent with a divergence at ?(c). ?(m) shows no characteristic length scale and has a nontrivial power-law form, ?(m)~R(-0.62), over almost the entire range of R at all ?. These results suggest that the force chains present in the spatial structure of the quenched stress may be governed by different physics than the anomalous elastic response near jamming. PMID:22243184

Karimi, K; Maloney, C E

2011-12-23

284

Local Anisotropy in Globally Isotropic Granular Packings  

NASA Astrophysics Data System (ADS)

We report on two-dimensional computer simulations of frictionless granular packings at various area fractions ? above the jamming point ?c. We measure the anisotropy in coarse-grained stress ?s and shear modulus ?m as functions of coarse-graining scale, R. ?s can be collapsed onto a master curve after rescaling R by a characteristic length scale ? and ?s by an anisotropy magnitude A. Both A and ? accelerate as ???c from above, consistent with a divergence at ?c. ?m shows no characteristic length scale and has a nontrivial power-law form, ?m˜R-0.62, over almost the entire range of R at all ?. These results suggest that the force chains present in the spatial structure of the quenched stress may be governed by different physics than the anomalous elastic response near jamming.

Karimi, K.; Maloney, C. E.

2011-12-01

285

Packing of charged chains on toroidal geometries  

NASA Astrophysics Data System (ADS)

We study a strongly adsorbed flexible polyelectrolyte chain on tori. In this generalized Thomson problem, the patterns of the adsorbed chain are analyzed in the space of the toroidal coordinates and in terms of the orientation of each chain segment. Various patterns are found, including double spirals, disclination-like structures, Janus tori, and uniform wrappings, arising from the long-range electrostatic interaction and the toroidal geometry. Their broken mirror symmetry is quantitatively characterized by introducing an order parameter, an integral of the torsion. The uniform packing, which breaks the mirror symmetry the least, has the lowest value of the order parameter. In addition, it is found that the electrostatic energy of confined chains on tori conforms to a power law regardless of the screening effect in some typical cases studied. Furthermore, we study random walks on tori that generate chain configurations in the large screening limit or at large thermal fluctuation; some features associated with the toroidal geometry are discussed.

Yao, Zhenwei; de la Cruz, Monica Olvera

2013-01-01

286

Hydrodynamics of a packed countercurrent column for the gas extraction  

SciTech Connect

The hydraulic capacity of a countercurrent column with gauze packing was examined at pressures between 8 and 30 MPa and temperatures between 313 and 373 K. The systems used were water + carbon dioxide, aqueous surfactant solution + carbon dioxide, and Toco, a substance whose physical properties are roughly similar to those of {alpha}-Tocopherol + carbon dioxide. A distinctive change in the flooding mechanisms from liquid layer flooding to bubble column flooding was observed. The different liquids, water and Toco, showed the same flooding behavior, indicating that the influence of the density on the flooding behavior prevails over the influence of any other physical property of the liquid. The foamability of the surfactant solution decreased significantly with increasing pressure--its influence on the flooding behavior could not be proved. The liquid holdup ranged between 2% and 6%. The dry pressure drop adhered to the Ergun equation.

Stockfleth, R.; Brunner, G.

1999-10-01

287

Mechanical-hydraulic integration modeling and simulation of hydraulic support  

Microsoft Academic Search

Based on Virtual Prototyping Technology, the co-simulation technology for mining machinery has been studied and applied. Hydraulic support is used as an example and the whole virtual prototype model of hydraulic ramming device was established, the co-simulation between mechanical system and control system is realized by means of software ADAMS and EASY5. The response of hydraulic support's mechanical system and

Lirong Wan; Xiaowang Wu; Chenglong Wang; Xin Zhang

2010-01-01

288

Hydraulic contacts controlling water flow across porous grains.  

PubMed

Water flow between porous grains varies widely depending on the water distribution in contacts between grains. The hydraulic behavior of contacts varies from highly conductive when water fills the contacts to a bottleneck to flow as water pressure drops and contact asperities rapidly drain. Such changes greatly impact the hydraulic conductivity of porous grain packs such as aggregated soil. The dominant driving force of water flow across contacts is capillarity, often quantified relative to gravity and viscous forces using the capillary and Bond numbers. For fast water infiltration, viscous forces dominate. For simplicity we modeled the water distribution between spherical porous grains whose surfaces are covered by spherical bumps of much smaller radii. We provide experimental evidence obtained by neutron radiography and synchrotron-based x-ray tomographic microscopy documenting transitions in the flow behavior across contacts. PMID:17930146

Carminati, A; Kaestner, A; Flühler, H; Lehmann, P; Or, D; Lehmann, E; Stampanoni, M

2007-08-21

289

Technical-Evaluation Report on the Proposed Technical-Specification Changes for the Inservice Surveillance of Safety-Related Hydraulic and Mechanical Snubbers at the James A. Fitzpatrick Nuclear Power Plant (Docket No. 50-333).  

National Technical Information Service (NTIS)

This report documents the technical evaluation of the proposed Technical Specification changes to Limiting Conditions for Operation, Surveillance Requirements and Bases for safety-related hydraulic and mechanical snubbers at the James A. FitzPatrick Nucle...

J. C. Selan

1983-01-01

290

Well sand packing prevention method  

SciTech Connect

A method is described of preventing sand packing in a producing well completed in a zone adjacent a hydrocarbon-bearing subterranean formation, comprising the steps of: producing fluid from the hydrocarbon-bearing formation, the fluid comprising an aqueous phase and a hydrocarbon phase; and, simultaneously with the fluid production, injecting a sand control agent into the well adjacent the production zone at a rate to obtain a wellhead concentration of the sand control agent in the aqueous phase of the fluid of from about 10 to about 1000 ppm active. The sand control agent is a quaternized acylated condensed alkanolamine.

Chakrabarty, T.; Thomas, R.

1986-11-18

291

Aircraft hydraulic systems. Third edition  

SciTech Connect

The first nine chapters concern hydraulic components including: tubing, hoses, fittings, seals, pumps, valves, cylinders, and motors. General hydraulic system considerations are included in chapters five and nine, while pneumatic systems are covered in chapter ten. Chapters eleven through fifteen are devoted to aircraft-specific systems such as: landing gear, flight controls, brakes, etc. The material is rounded out with excerpts from the Canadair Challenger 601 training guide to illustrate the use of hydraulic systems in a specific aircraft application.

Neese, W.A.

1991-12-31

292

Dual-purpose hydraulic fluid  

US Patent & Trademark Office Database

A synthetic dual-purpose fluid for use as a hydraulic fluid and in metal cutting operations, particularly where hydraulic fluid leakage cannot be tolerated in hydraulically operated machines designed for metal cutting purposes. The fluid contains in combination 50-70% of an alkylene glycol, 10 to 25% of an alkanol amine, up to 10% boric acid, and 2 to 25% of a phosphate-modified condensation product of a fatty acid and a dialkanolamine.

1980-06-24

293

Application of smart material-hydraulic actuators  

NASA Astrophysics Data System (ADS)

The application of a new class of actuators is considered. The actuators under development combine a high energy density smart material, specifically a piezoelectric material, with internal servohydraulic components. Large displacement outputs are produced, while the high force capacity of the stiff smart material is retained, for a net high-energy output. The actuator is considered "power-by-wire" because only electrical power is provided from the vehicle or system controller. A primary motivating application is in unmanned combat air vehicles (UCAVs). The particular actuation needs of these vehicles, in flight control and other utility functions, are described and distilled to a set of relevant device requirements. Other potential applications, such as flight motion simulation, are also highlighted. The new actuation architecture offers specific advantages over centralized hydraulic systems and has capabilities not present in electromechanical actuators (EMAs). The main advantage over centralized hydraulic systems is the elimination of the need for hydraulic lines. Compared to motor-driven ball screw type EMAs, the new actuators offer higher frequency response, and a larger peak-to-average output. A laboratory test facility designed to represent the loading experienced by a UCAV control surface is described. Key steps necessary to flight qualify the actuator are introduced.

Anderson, Eric H.; Bales, Gregory L.; White, Edward V.

2003-08-01

294

Hydraulic systems performance of Army engine oils  

SciTech Connect

A technical evaluation of qualified military specification lubricants was started by the U.S. Army Belvoir Research and Development Center and was performed at the U.S. Army Fuels and Lubricants Research Laboratory (AFLRL) located at Southwest Research Institute. This work was conducted to determine if such lubricants can be used as hydraulic fluids in Army Commercial Construction Equipment (CCE) and Selected Material Handling Equipment (SMHE). Sixteen military specification lubricants were extensively evaluated using twelve selected tests required by equipment manufacturers and one test developed by AFLRL in conjunction with John Deere. From the data developed, lubricants meeting Army specifications passed 88 percent of all the tests. It appears that the Army engine oils are good potential candidates for use as hydraulic and power transmission lubricants within the Army CCE/SMHE systems. Areas of concern include copper corrosion, wet brake/clutch frictional performance, and final drive gear wear.

Marbach, H.W.; Lestz, S.J.

1984-01-01

295

110. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

110. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL PANEL IN UMBILICAL MAST PUMP ROOM (109), LSB (BLDG. 770) ACCUMULATOR FOR MAST RETRACTION ON LEFT. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

296

128. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

128. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL PANEL IN UMBILICAL MAST PUMP ROOM (209), LSB (BLDG. 751). PUMP ON RIGHT; ACCUMULATOR FOR MAST RETRACTION ON LEFT. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

297

Iterative packing for demand matching and sparse packing.  

SciTech Connect

The main result we will present is a 2k-approximation algorithm for the following 'k-hypergraph demand matching' problem: given a set system with sets of size <=k, where sets have profits & demands and vertices have capacities, find a max-profit subsystem whose demands do not exceed the capacities. The main tool is an iterative way to explicitly build a decomposition of the fractional optimum as 2k times a convex combination of integral solutions. If time permits we'll also show how the approach can be extended to a 3-approximation for 2-column sparse packing. The second result is tight w.r.t the integrality gap, and the first is near-tight as a gap lower bound of 2(k-1+1/k) is known.

Parekh, Ojas

2010-11-01

298

The Packing of Granular Polymer Chains  

SciTech Connect

Rigid particles pack into structures, such as sand dunes on the beach, whose overall stability is determined by the average number of contacts between particles. However, when packing spatially extended objects with flexible shapes, additional concepts must be invoked to understand the stability of the resulting structure. Here, we examine the disordered packing of chains constructed out of flexibly connected hard spheres. Using x-ray tomography, we find that long chains pack into a low-density structure whose mechanical rigidity is mainly provided by the backbone. On compaction, randomly oriented, semi-rigid loops form along the chain, and the packing of chains can be understood as the jamming of these elements. Finally, we uncover close similarities between the packing of chains and the glass transition in polymers.

Zou, Ling-Nan; Cheng, Xiang; Rivers, Mark L.; Jaeger, Heinrich M.; Nagel, Sidney R.; UC

2009-12-01

299

Dual hydraulic safety valve  

SciTech Connect

This patent describes a subsurface well safety valve for controlling the fluid flow through a well conduit and including a housing having a bore and a valve closure member moving between open and closed positions for controlling the fluid flow through the bore, a tubular member telescopically moving in the housing for controlling the movement of the valve closure member. The improvement in fluid actuating means for actuating the valve closure member comprising, a first piston and cylinder assembly in the housing adapted to be connected to a hydraulic control line, the first assembly connected to the tubular member, a second piston and cylinder assembly in the housing adapted to be connected to a hydraulic control line, the second assembly disconnected from the tubular member, and means for disconnecting the first assembly from the tubular member and connecting the second assembly to the tubular member. The method of operating a subsurface well safety valve for controlling the fluid flow through a well conduit in which the valve includes a housing having a bore and a valve closure member moving between open and closed positions for controlling the fluid flow through the bore.

Leismer, D.D.; Blizzard, W.A. Jr.

1989-06-13

300

FOREWORD: 26th IAHR Symposium on Hydraulic Machinery and Systems  

NASA Astrophysics Data System (ADS)

The 26th IAHR Symposium on Hydraulic Machinery and Systems, will be held in Beijing, China, 19-23 August 2012. It is jointly organized by Tsinghua University, State Key Laboratory of Hydro Science and Hydraulic Engineering, China, Jiangsu University, Xi'an University of Technology, China Agricultural University, National Engineering Research Center of Hydropower Equipment and Dongfang Electric Machinery Co., Ltd. It is the second time that China hosts such a symposium. By the end of 2011, the China electrical power system had a total of 1 050 GW installed power, out of which 220 GW was in hydropower plants. The energy produced in hydropower facilities was 662.6 TWh from a total of 4,720 TWh electrical energy production in 2011. Moreover, in 2020, new hydropower capacities are going to be developed, with a total of 180 GW installed power and an estimated 708 TWh/year energy production. And in 2011, the installed power of pumped storage stations was about 25GW. In 2020, the data will be 70GW. At the same time, the number of pumps used in China is increasing rapidly. China produces about 29,000,000 pumps with more than 220 series per year. By the end of 2011, the Chinese pumping system has a total of 950 GW installed power. The energy consumed in pumping facilities was 530 TWh in 2011. The pump energy consumption accounted for about 12% of the national electrical energy production. Therefore, there is a large market in the field of hydraulic machinery including water turbines, pump turbines and a variety of pumps in China. There are also many research projects in this field. For example, we have conducted National Key Research Projects on 1000 MW hydraulic turbine, and on the pump turbines with high head, as well as on the large capacity pumps for water supply. Tsinghua University of Beijing is proud to host the 26th IAHR Symposium on Hydraulic Machinery and Systems. Tsinghua University was established in 1911, after the founding of the People's Republic of China. It was molded into a polytechnic institute focusing on engineering in the nationwide restructuring of universities and colleges undertaken in 1952. At present, the university has 14 schools and 56 departments with faculties in science, engineering, humanities, law, medicine, history, philosophy, economics, management, education and art. The University now has over 25 900 students, including 13 100 undergraduates and 12 800 graduate students. As one of China's most renowned universities, Tsinghua has become an important institution for fostering talents and scientific research. The International Association of Hydro-Environment Engineering and Research (IAHR) particularly promotes the advancement and exchange of knowledge through working groups, specialty symposia, congresses, and publications on water resources, river and coastal hydraulics, risk analysis, energy, environment, disaster prevention, and industrial processes. The IAHR Committee on Hydraulic Machinery and Systems deals with the advancement of technology associated with the understanding of steady and unsteady flow characteristics in hydraulic machinery and conduit systems connected to the machinery. The technology elements include the fluid behaviour within machine components, hydro-elastic behaviour of machine components, cavitation and two phase flow in turbines and pumps, hydraulic machine and plant control systems, the use of hydraulic machines to improve water quality, and even considerations to improve fish survival in their passage through hydro plants. The main emphases of the IAHR Committee on Hydraulic Machinery and Systems are to stimulate research and understanding of the technologies associated with hydraulic machinery and to promote interaction between the machine designers, machine users, the academic community, and the community as a whole. Hydraulic machinery is both cost effective and environmentally friendly. The goals of the IAHR Committee on Hydraulic Machinery and Systems are to improve the value of hydraulic machinery to the end user, to the societies, and to improve societies u

Wu, Yulin; Wang, Zhengwei; Liu, Shuhong; Yuan, Shouqi; Luo, Xingqi; Wang, Fujun

2012-11-01

301

A brushless motor drive with sensorless control for commercial vehicle hydraulic pumps  

Microsoft Academic Search

The paper describes the electronic design of a brushless motor drive powering a hydraulic Motor-Pump-Unit (MPU) for automotive applications. The full MPU consists of a Permanent Magnet (PM) brushless motor, a three-phase MOSFET inverter with digital control and a gear pump for the hydraulic circuit. The MPU designed in this project is characterized by low voltage supply and high hydraulic

M. Bonfe; Michele Bergo

2008-01-01

302

The Design of Four-Bar Linkage of Large Inclined Angle Hydraulic Support  

Microsoft Academic Search

Four-bar linkage is one of the most important components of shield-type powered support or chock-shield-type hydraulic support. Parameterized modeling, simulation and optimization of four-bar linkage is firstly accomplished by use of ADAMS software in designing a large inclined angle hydraulic support. Then based on three-dimension model of the whole hydraulic support, applying COSMOS\\/Works software, finite element analysis is made under

Xin Zhang; Qingliang Zeng; Jianwu Zhang; Hanzheng Dai

2009-01-01

303

Dynamic analysis of wave energy converter by incorporating the effect of hydraulic transmission lines  

Microsoft Academic Search

A heaving-buoy wave energy converter equipped with hydraulic power take-off is studied in this paper. This wave energy converter system is divided into five subsystems: a heaving buoy, hydraulic pump, pipelines, non-return check valves and a hydraulic motor combined with an electric generator. A dynamic model was developed by considering the interactions between the subsystems in a state space form.

Limin Yang; Torgeir Moan

2011-01-01

304

A note on online hypercube packing  

Microsoft Academic Search

In this paper, we study an online multi-dimensional bin packing problem where all items are hypercubes. Hypercubes of different\\u000a size arrive one by one, and we are asked to pack each of them without knowledge of the next pieces so that the number of bins\\u000a used is minimized. Based on the techniques from one dimensional bin packing and specifically the

Xin Han; Deshi Ye; Yong Zhou

2010-01-01

305

Field Correction for Component Pack packaged with ...  

Center for Biologics Evaluation and Research (CBER)

... Field Correction for Component Pack packaged with Mononine (Coagulation Factor IX, Human)-CSL Behring. DATE NOTIFICATION INITIATED: ... More results from www.fda.gov/biologicsbloodvaccines/safetyavailability/recalls

306

Random packing of spheres in Menger sponge  

NASA Astrophysics Data System (ADS)

Random packing of spheres inside fractal collectors of dimension 2 < d < 3 is studied numerically using Random Sequential Adsorption (RSA) algorithm. The paper focuses mainly on the measurement of random packing saturation limit. Additionally, scaling properties of density autocorrelations in the obtained packing are analyzed. The RSA kinetics coefficients are also measured. Obtained results allow to test phenomenological relation between random packing saturation density and collector dimension. Additionally, performed simulations together with previously obtained results confirm that, in general, the known dimensional relations are obeyed by systems having non-integer dimension, at least for d < 3.

Cie?la, Micha?; Barbasz, Jakub

2013-06-01

307

Random close packing of polydisperse jammed emulsions  

NASA Astrophysics Data System (ADS)

Packing problems are everywhere, ranging from oil extraction through porous rocks to grain storage in silos and the compaction of pharmaceutical powders into tablets. At a given density, particulate systems pack into a mechanically stable and amorphous jammed state. Theoretical frameworks have proposed a connection between this jammed state and the glass transition, a thermodynamics of jamming, as well as geometric modeling of random packings. Nevertheless, a simple underlying mechanism for the random assembly of athermal particles, analogous to crystalline ordering, remains unknown. Here we use 3D measurements of polydisperse packings of emulsion droplets to build a simple statistical model in which the complexity of the global packing is distilled into a local stochastic process. From the perspective of a single particle the packing problem is reduced to the random formation of nearest neighbors, followed by a choice of contacts among them. The two key parameters in the model, the available space around a particle and the ratio of contacts to neighbors, are directly obtained from experiments. Remarkably, we demonstrate that this ``granocentric'' view captures the properties of the polydisperse emulsion packing, ranging from the microscopic distributions of nearest neighbors and contacts to local density fluctuations and all the way to the global packing density. Further applications to monodisperse and bidisperse systems quantitatively agree with previously measured trends in global density. This model therefore reveals a general principle of organization for random packing and lays the foundations for a theory of jammed matter.

Brujic, Jasna

2010-03-01

308

14 CFR 25.1435 - Hydraulic systems.  

Code of Federal Regulations, 2013 CFR

...designed to use any suitable hydraulic fluid specified by the...must be conducted on the hydraulic system(s...failure conditions, and to support or validate element design. (3) The complete hydraulic system(s)...

2013-01-01

309

14 CFR 25.1435 - Hydraulic systems.  

Code of Federal Regulations, 2010 CFR

...designed to use any suitable hydraulic fluid specified by the...must be conducted on the hydraulic system(s...failure conditions, and to support or validate element design. (3) The complete hydraulic system(s)...

2010-01-01

310

14 CFR 25.1435 - Hydraulic systems.  

Code of Federal Regulations, 2010 CFR

...designed to use any suitable hydraulic fluid specified by the...must be conducted on the hydraulic system(s...failure conditions, and to support or validate element design. (3) The complete hydraulic system(s)...

2009-01-01

311

14 CFR 29.1435 - Hydraulic systems.  

Code of Federal Regulations, 2010 CFR

...systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each element of the hydraulic system must be designed to withstand... (2) Each element of the hydraulic system must be designed to...

2010-01-01

312

HYDRAULIC CONTROL ROD DRIVE MECHANISM  

Microsoft Academic Search

The hydraulic control rod drive mechanism described is housed in a ; thimble attached to and extending outward from the reactor vessel. The drive ; mechanism uses reactor coolant medium as the hydraulic fluid. Within the housing ; there are two concentrically arranged hollow, cylindrically shaped members to one ; of which the piston is attached. One of the two

Kumpf

1963-01-01

313

POLYCRYSTALLINE DIAMOND COMPACT BIT HYDRAULICS  

Microsoft Academic Search

It is well understood and documented that bottomhole hydraulics plays an important role in conventional diamond bit performance. Recent industry experience has shown a similar importance with the new synthetic diamond compact bits. Certain types of polycrystalline diamond compact bits have cutters arranged in a reverse spiral mode. For optimum performance bit hydraulic design should be tailored to that reverse

R. H. Knowlton; Hsin Huang; B. Iversen

1982-01-01

314

Tractor Hydraulics. A Teaching Reference.  

ERIC Educational Resources Information Center

|The manual was developed to help provide a better understanding of how and why hydraulic principles serve the purposes of weight reduction, increase of physical effort, and more precise control to machines of all types. The four components that are necessary to have a workable hydraulic system--a reservoir, a pump, a valve, and a motor (cylinder)…

American Association for Vocational Instructional Materials, Athens, GA.

315

Superheater Hydraulic Model Test Plan.  

National Technical Information Service (NTIS)

The plan for conducting a hydraulic test on a full scale model of the AI Steam Generator Module design is presented. The model will incorporate all items necessary to simulate the hydraulic performance characteristics of the superheater but will utilize m...

M. Gabler R. M. Oliva

1973-01-01

316

Hydraulically actuated well shifting tool  

SciTech Connect

This patent describes a hydraulically actuated shifting tool for actuating a sliding member in a well tool. It comprises: a housing having a hydraulic fluid bore therein; shifting dog means positioned on the housing for movement away and toward the housing; locking dog means positioned on the housing for movement away and toward the body; shifting dog hydraulic actuating means in fluid communication with the bore for causing engagement of the shifting dogs with the sliding member; locking dog hydraulic actuating means in communication with the bore for causing engagement of the locking dogs with the locking means; and hydraulic shifting means in communication with the bore for causing relative movement between the shifting dog means and the locking dog means for shifting the sliding sleeve.

Roth, B.A.

1992-10-20

317

29 CFR 1926.302 - Power-operated hand tools.  

Code of Federal Regulations, 2013 CFR

...valve which must be held open manually. A support shall be provided on which the nozzle may...and E of this part, shall apply. (d) Hydraulic power tools. (1) The fluid used in hydraulic powered tools shall be...

2013-07-01

318

Microbial community analysis in biocathode microbial fuel cells packed with different materials  

PubMed Central

Biocathode MFCs using microorganisms as catalysts have important advantages in lowering cost and improving sustainability. Electrode materials and microbial synergy determines biocathode MFCs performance. In this study, four materials, granular activated carbon (GAC), granular semicoke (GS), granular graphite (GG) and carbon felt cube (CFC) were used as packed cathodic materials. The microbial composition on each material and its correlation with the electricity generation performance of MFCs were investigated. Results showed that different biocathode materials had an important effect on the type of microbial species in biocathode MFCs. The microbes belonging to Bacteroidetes and Proteobacteria were the dominant phyla in the four materials packed biocathode MFCs. Comamonas of Betaproteobacteria might play significant roles in electron transfer process of GAC, GS and CFC packed biocathode MFCs, while in GG packed MFC Acidovorax may be correlated with power generation. The biocathode materials also had influence on the microbial diversity and evenness, but the differences in them were not positively related to the power production.

2012-01-01

319

Hydraulic fracture analysis method  

SciTech Connect

A method of determining the orientation of a hydraulic fracture plane in the earth is described, consisting of: positioning an array of sensors for measuring seismic ground motion above a region which includes the fracture, providing a well bore having fluid therein communicating with the fracture to be defined, perturbing the fluid to cause transient pressure or flow oscillations in the fluid column in the well bore, measuring seismic ground motion induced by the transient pressure and flow oscillations in the fracture, calculating, using theory of wave propagation, the ground motion expected of fractures of different orientations, comparing the measured ground motion with the calculated ground motion patterns representing fractures of different orientations, selecting the fracture orientation that yields calculated seismic ground motions most closely resembling the measured seismic ground motions as the most probable fracture orientation, and calculating a probable fracture orientation based on the seismic motion of the ground.

Holzhausen, G.R.; St. Lawrence, W.

1989-01-31

320

High temperature hydraulic seals  

NASA Astrophysics Data System (ADS)

This program investigated and evaluated high temperature hydraulic sealing technology, including seals, fluids, and actuator materials. Test limits for fluid pressure and temperature were 8000 psi and 700 F respectively. The original plan to investigate CTFE fluid at 350 F as well as other fluids at higher temperatures was reduced in scope to include only the higher temperature investigation. Seals were obtained from 11 manufacturers. Design requirements including materials, dimensions, clearances, and tolerances were established and test modules were constructed from the detail designs which were produced. Nine piston seals and one rod seal were tested at temperatures ranging from -65 to +600 F and pressures to 6000 psi. Fluid performance under these conditions was evaluated. Details of this activity and results of the effort are summarized in this report.

Williams, K. R.

1993-05-01

321

Market and Cost Structure in the U.S. Beef Packing Industry: A Plant-Level Analysis  

Microsoft Academic Search

A resurgence of consolidation in the U.S. meat packing industry in the past few decades has stimulated academic and policy debate. Issues raised include the role of cost economies in driving these patterns, and the effects on the agricultural sector (cattle producers) from market power. Here, plant level cost and revenue data for U.S. beef packing plants are used to

Catherine J. Morrison Paul

2001-01-01

322

Method of operating a hydraulic turbine or a pump-turbine  

SciTech Connect

A method of operating a hydraulic turbine is described in which, when the hydraulic turbine is operated so as to shift the load from the watered condition at guide vanes closed to the generating operation area in a condition that the runner rotates in the turbine rotating direction, the hydraulic machine is temporarily disconnected from the electric power system thereby to decrease the revolution per minute and to allow the load to smoothly shift from the motoring operation to the power generation operation in the version of the hydraulic machine characteristic, and under this condition, the guide vane is gradually opened to set the revolution per minute to a given value, and then the hydraulic machine is recoupled with the electric power system for gaining the load.

Yokoyama, T.

1981-05-12

323

Method for fabricating a rechargeable electrical cell pack having over-current protection  

SciTech Connect

A rechargeable electrochemical cell pack is provided having a casing holding a plurality of electrically interconnected cells and having circuit breaking means to guard against the possibility of excessive supply and consumption of electrical power and the risk of damage or injury incident thereto. The circuit breaker comprises a small current fuse contained internally of the cell pack so as to give an external visible indication of its state and is removably mounted on an access door for replacement purposes.

Leffingwell, E.A.

1982-02-16

324

Transition Behavior of Packed-Bed Dielectric Barrier Discharge in Argon  

Microsoft Academic Search

In this paper, we present the transition behavior of the argon discharge generated in a BaTiO3 packed-bed dielectric- barrier-discharge reactor. A combination of surface discharge and microdischarge can be found in the packed-bed plasma reactor. With the increase of discharge power, microdischarge starts to expand and spread into the surface discharge covering a much larger area on the pellet surface,

Xin Tu; Helen J. Gallon; J. Christopher Whitehead

2011-01-01

325

Modelling of cooling tower splash pack  

Microsoft Academic Search

A mathematical model and a computer simulation program have been developed for the modelling of counterflow cooling tower splash pack thermal performance. The one-dimensional model uses basic aerodynamic, hydrodynamic and heat\\/mass transfer information to predict the performance of the packing material without depending on cooling tower test data. The predicted transfer characteristics and pressure drop data obtained with the simulation

A. A. Dreyer; P. J. Erens

1996-01-01

326

Probe with integrated heater and thermocouple pack  

SciTech Connect

This patent describes a gamma thermometer probe for detecting heat produced within the thermometer probe. It comprises: an outer elongate thermometer sheath; an elongate rod; annular recesses; a longitudinal bore; and an integrated thermocouple pack. The thermocouple pack comprises: a first type wire, and second type wires. The second type wires comprises: an outer section; and an inner segment.

McCulloch, R.W.; Dial, R.E.; Finnell, W.F.R.

1988-02-16

327

Near-Optimal Bin Packing Algorithms.  

National Technical Information Service (NTIS)

The Bin Packing problem is a model for a number of problems occurring in industry and computer science. Suppose a list of pieces with sizes between 0 and 1, and a sequence of unit-capacity bins is given. The goal is to pack the pieces into as few bins as ...

D. S. Johnson

1973-01-01

328

NEW TEACHER WELCOME PACK: ELEMENTARY SCHOOL  

NSDL National Science Digital Library

Assortment of "Best-Selling" books for Elementary School Teachers. Pack includes the following books. Picture Perfect Science, Exemplary Science Grades K-4, Uncovering Student Ideas in Science, Volume 1, Using Science Notebooks, and Everyday Science Mysteries. Books are packed into a waterproof, nylon briefcase with handle and shoulder strap. Front flap of briefcase is printed with the NSTA logo.

1900-01-01

329

Is incest common in gray wolf packs?  

Microsoft Academic Search

Wolf packs generally consist of a breeding pair and their maturing of&pring that help provision and protect pack young. Because the reproductive tenure in wolves is often short, reproductively mature offspring might replace their parents, resulting in sibling or parent-offspr ing matings. To determine the extent of incestuous pairings, we measured relatedness based on variability in 20 microsatellit e loci

Deborah Smith; Thomas Meier; Eli Geffen; L. David Mech; John W. Burch; Layne G. Adams; Robert K. Wayne

1997-01-01

330

Method of gravel packing a well  

SciTech Connect

The present invention relates to a thermally stable crosslinked gel gravel packing fluid for use in the treatment of highly deviated well bores penetrating a subterranean formation. The gravel packing fluid comprises an aqueous liquid, a gelling agent comprising a selected modified cellulose ether, a crosslinking agent, a breaker, a particulate agent and any additional additives that may be present.

Almond, S. W.; Himes, R. E.

1985-11-12

331

Cost Driver Analysis for Tray Pack Foods.  

National Technical Information Service (NTIS)

Tray Pack foods are one of the primary ration sources for the new Army Combat Field Feeding System. Cost and Quality Control are necessary for all facets of the Tray Pack manufacturing process: from the distribution and warehousing of raw materials, prepa...

J. M. Smith

1988-01-01

332

Lattice approaches to packed column simulations  

Microsoft Academic Search

This work presents a review of the findings into the ability of a digitally based particle packing algorithm, called DigiPac, to predict bed structure in a variety of packed columns, for a range of generic pellet shapes frequently used in the chemical and process engineering industries. Resulting macroscopic properties are compared with experimental data derived from both invasive and non-destructive

Richard Caulkin; Xiaodong Jia; Mike Fairweather; Richard A. Williams

2008-01-01

333

McDonald's Ecology Action Pack.  

ERIC Educational Resources Information Center

|This ecology pack, designed for teacher use, focuses on the development of environmental awareness. The materials in the pack are designed to be used to introduce existig units of study, serve as a high interest supplement, or as a source of special projects. They are intended to stimulate thinking and activity that will carry beyond the school.…

McDonald's Corp., Oak Brook, IL.

334

Compact attic mounted solar heating pack assembly  

Microsoft Academic Search

A compact attic solar heating pack assembly for mounting within a building attic having south and north facing roof sections overlying a horizontal building attic floor forming the ceiling and defining an enclosed attic space above the occupied room space below the ceiling is described. The pack assembly comprises: a closed sheet metal plenum, means for fixedly mounting the plenum

1988-01-01

335

Water hydraulics - A novel design of spool-type valves for enhanced dynamic performance  

Microsoft Academic Search

Hydraulic systems provide the most powerful actuators available. In the last decades however, their use in mechatronic systems has decreased, mainly because of two factors: the nature of the actuators themselves (such as noise, cleanliness, size) and the ease of use of electric systems. Water hydraulics, which use water instead of oil as working medium, have several advantages and could

Y. S. Yang; C. Semini; N. G. Tsagarakis; D. G. Caldwell; Yuquan Zhu

2008-01-01

336

Free-form estimation of the unsaturated soil hydraulic properties by inverse modeling using global optimization  

Microsoft Academic Search

Inverse modeling is a powerful technique for identifying the hydraulic properties of unsaturated porous media. However, the selection of an appropriate parameterization of the soil water retention and hydraulic conductivity function remains a challenge. In this article, we present an improved algorithm for estimating these two relationships without assigning an a priori shape to them. The approach uses cubic Hermite

S. C. Iden; W. Durner

2007-01-01

337

Numerical prediction of erosion on guide vanes and in labyrinth seals in hydraulic turbines  

Microsoft Academic Search

Erosion in hydraulic power plants is caused by sand particles in the flow. This is one of the major problems that restricts the lifetime between overhauls of water turbines. Especially those parts of the hydraulic turbine which are exposed to high flow velocities bear a considerable risk of being damaged by erosion processes. Therefore, suitable methods for the prediction of

Reiner Mack; Peter Drtina; Egon Lang

1999-01-01

338

Genetic aided scheduling of hydraulically coupled plants in hydro-thermal coordination  

Microsoft Academic Search

Scheduling of hydraulically coupled plants (HCPs) has been reckoned as one of the most difficult parts of the problem of hydro-thermal power system coordination. This paper presents an efficient approach to the 24-hour ahead generation scheduling of HCPs based on genetic algorithms. In this paper, the difficult water balance constraints caused by hydraulic coupling are embedded and satisfied throughout the

Po-Hung Chenl; Hong-Chan Chang

1996-01-01

339

The Design and Research of PC Software in Hydraulic Supports Control System Based on VC++  

Microsoft Academic Search

The real-time monitoring of operational status in coal face can reduce the occurrence of risk effectively and prevent the further expansion of risk. This paper introduces a PC software in hydraulic supports control system based on VC++ through the investigation of coal face and the mathematical model of electric hydraulic and powered support control system. VC++ 6.0 was used to

Zhang Wei; Shi Xue-dong; Wu He-jin

2010-01-01

340

Optimization Design of the Hydraulic Pipeline based on the Principle of Saving Energy Sources  

Microsoft Academic Search

The size of hydraulic pipeline affects the energy loss when the power transmits through it, and it affects the volume and the weight of pipe directly. Based on the principle of saving energy sources, the paper introduces the method of optimization design. Object function of hydraulic pipeline is built which considers both energy loss and pipeline's volume, and the result

Yongbai Sha; Xiaoying Zhao

2010-01-01

341

Temporal scaling of hydraulic head and river base flow and its implication for groundwater recharge  

Microsoft Academic Search

Spectral analyses were conducted for hourly hydraulic head (h) data observed over a 4-year period at seven monitoring wells in the Walnut Creek watershed, Iowa. The log power spectral density of the hydraulic head fluctuations versus log frequency (f) at all seven wells is shown to have a distinct slope or fractal dimension (D), indicating temporal scaling in the time

You-Kuan Zhang; Keith Schilling

2004-01-01

342

29 CFR 1926.305 - Jacks-lever and ratchet, screw, and hydraulic.  

Code of Federal Regulations, 2010 CFR

...Labor 8 2010-07-01 2010-07-01 false Jacks-lever and ratchet, screw, and hydraulic. 1926.305 Section...CONSTRUCTION Tools-Hand and Power § 1926.305 Jacksâlever and ratchet, screw, and hydraulic. (a) General...

2010-07-01

343

29 CFR 1926.305 - Jacks-lever and ratchet, screw, and hydraulic.  

Code of Federal Regulations, 2010 CFR

...Labor 8 2009-07-01 2009-07-01 false Jacks-lever and ratchet, screw, and hydraulic. 1926.305 Section...CONSTRUCTION Tools-Hand and Power § 1926.305 Jacksâlever and ratchet, screw, and hydraulic. (a) General...

2009-07-01

344

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT X, AUTOMATIC TRANSMISSIONS--HYDRAULIC SYSTEMS (PART II).  

ERIC Educational Resources Information Center

THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO PROVIDE A SUMMARY OF MAINTENANCE PROCEDURES FOR AUTOMATIC TRANSMISSIONS USED ON DIESEL POWERED VEHICLES. TOPICS ARE (1) CHECKING THE HYDRAULIC SYSTEM, (2) SERVICING THE HYDRAULIC SYSTEM, (3) EXAMINING THE RANGE CONTROL VALVE, (4) EXAMINING THE LOCK-UP AND FLOW VALVE, (5) EXAMINING THE MAIN REGULATOR…

Human Engineering Inst., Cleveland, OH.

345

Electrocautery-induced ignition of tonsillar packing.  

PubMed

A recent case of ignition of a bismuth-subgallate pack during routine tonsillectomy prompted this investigation of local oxygen levels. Similar conditions were reproduced in the laboratory to determine their influence on the flammability of materials commonly used to aid in haemostasis. Cotton tonsil packs soaked in saline, adrenalin, or adrenalin and bismuth were compared. During spontaneous ventilation through an age-appropriate uncuffed endotracheal tube, an air leak rarely occurred. However, when assisted ventilation was used, an airway leak produced an elevated oxygen concentration in 8 of 10 children. This was associated with increased combustibility of the packs, regardless of solution mixture. The addition of bismuth further increased combustibility. Partially saturated packs appeared to be more combustible than fully saturated packs. PMID:7897773

Macdonald, M R; Wong, A; Walker, P; Crysdale, W S

1994-12-01

346

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

NASA Astrophysics Data System (ADS)

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

Shi, Q.

2010-08-01

347

Powertrain System HANT: Hydraulic Pump/Motor  

SciTech Connect

The development of the new Hydraulic Pump/Motor is the main part of the Powertrain-System HANT. Several Engineering Models of the same design have been tested to prove that the new concept is effective. The important ranges: Maximum pressure and rpm and low power (low pressure, rpm, swashplate angle) were tested successfully. The efficiencies in all areas have already shown the same or better data then those of the best products on the market. The tests have been conducted in Switzerland (maximum power) in 1987 and at the UWM-Madison, Wisconsin (low power efficiency) in 1988. Based on these data and several new useful design features the Engineering Model has been updated. In addition, the reduction of unnecessary safety factor, new materials and mass-production like manufacturing methods, has lead to an significantly improved Prototype Design. The updated version and its expected improved technical data are presented in this report.

Not Available

1993-06-01

348

Electrokinetic high pressure hydraulic system  

SciTech Connect

A compact high pressure hydraulic pump having no moving mechanical parts for converting electric potential to hydraulic force. The electrokinetic pump, which can generate hydraulic pressures greater than 2500 psi, can be employed to compress a fluid, either liquid or gas, and manipulate fluid flow. The pump is particularly useful for capillary-base systems. By combining the electrokinetic pump with a housing having chambers separated by a flexible member, fluid flow, including high pressure fluids, is controlled by the application of an electric potential, that can vary with time.

Paul, Phillip H. (Livermore, CA); Rakestraw, David J. (Fremont, CA)

2000-01-01

349

Simulation study on hybrid ultracapactior-battery power system for PHEV  

Microsoft Academic Search

A hybrid power system composited by ultracapacitor and battery pack has been studied for battery packs only system is hard to meet the requirements of high specific power and energy reasonably. A Topology structure that the ultracapacitor system directly in series with DC\\/DC converter and then paralleled with battery pack were analyzed. The ultracapacitor, battery pack, DC\\/DC converter and hybrid

Xiong Rui; He Hongwen; Zhang Xiaowei; Wang Yi

2010-01-01

350

Laboratory imaging of stimulation fluid displacement from hydraulic fractures  

SciTech Connect

Laboratory experiments were conducted to physically investigate the processes governing stimulation fluid displacement from hydraulic fractures. Experiments were performed on two scales: meter-scale in a 1500 cm{sup 2} sand pack and core-scale in a 65 cm{sup 2} API linear conductivity cell. High-resolution light transmission imaging was employed at the meter-scale to visualize and quantify processes governing fluid displacement. For comparison, complimentary tests were performed using an API conductivity cell under ambient test conditions and at elevated closure stress. In these experiments viscous fingering and gravity drainage were identified as the dominant processes governing fluid displacement. Fluid viscosity was found to dictate the relative importance of the competing displacement processes and ultimately determine the residual liquid saturation of the sand pack. The process by which fluid displacement occurs was seen to effect the shape of both the gas and liquid phase relative permeability functions. Knowledge of such viscosity/relative permeability relationships may prove useful in bounding predictions of post-stimulation recovery of gels from the fracture pack.

Tidwell, V. [Sandia National Lab., Albuquerque, NM (United States); Parker, M. [SPE, Richardson, TX (United States)

1996-11-01

351

Design of hydraulic output Stirling engine  

Microsoft Academic Search

A hydraulic output system for the RE-1000 free piston stirling engine (FPSE) was designed. The hydraulic output system can be readily integrated with the existing hot section of RE-1000 FPSE. The system has two simply supported diaphragms which separate the engine gas from the hydraulic fluid, a dynamic balance mechanism, and a novel, null center band hydraulic pump. The diaphragms

W. M. Toscano; A. C. Harvey; K. Lee

1983-01-01

352

The Virtual Laboratory of Machine Tool Hydraulics  

NSDL National Science Digital Library

The Virtual Laboratory of Machine Tool Hydraulics is an interactive, web-based graphic animation of machine tool hydraulics. It includes fundamentals, troubleshooting, problem-solving, and interactive demonstrations of hydraulic circuits and components. This is a great interactive activity for those interested in learning the fundamental concepts of hydraulic systems.

Song, Xueshu

2009-10-29

353

Changes in entrapped gas content and hydraulic conductivity with pressure.  

PubMed

Water table fluctuations continuously introduce entrapped air bubbles into the otherwise saturated capillary fringe and groundwater zone, which reduces the effective (quasi-saturated) hydraulic conductivity, K(quasi), thus impacting groundwater flow, aquifer recharge and solute and contaminant transport. These entrapped gases will be susceptible to compression or expansion with changes in water pressure, as would be expected with water table (and barometric pressure) fluctuations. Here we undertake laboratory experiments using sand-packed columns to quantify the effect of water table changes of up to 250 cm on the entrapped gas content and the quasi-saturated hydraulic conductivity, and discuss our ability to account for these mechanisms in ground water models. Initial entrapped air contents ranged between 0.080 and 0.158, with a corresponding K(quasi) ranging between 2 and 6 times lower compared to the K(s) value. The application of 250 cm of water pressure caused an 18% to 26% reduction in the entrapped air content, resulting in an increase in K(quasi) by 1.16 to 1.57 times compared to its initial (0 cm water pressure) value. The change in entrapped air content measured at pressure step intervals of 50 cm, was essentially linear, and could be modeled according to the ideal gas law. Meanwhile, the changes in K(quasi) with compression-expansion of the bubbles because of pressure changes could be adequately captured with several current hydraulic conductivity models. PMID:22320934

Marinas, Maricris; Roy, James W; Smith, James E

2012-02-09

354

Electroslag Welding on Hydraulic Machinery.  

National Technical Information Service (NTIS)

The use of consumable guide electroslag welding process with components for hydraulic machinery having curved and profiled seams is described. Tests were carried out to optimize the welding parameters and the mechanical properties of welding joints with c...

E. Schorer F. J. Edel A. Borontschuk

1983-01-01

355

Fire Resistant Aircraft Hydraulic System.  

National Technical Information Service (NTIS)

This document reports a study to select a nonflammable hydraulic fluid for possible use in future military aircraft in which the Halocarbon Products Corporation AO-8 chlorotrifluoroethylene (CTFE) fluid was selected as the most promising fluid which meets...

E. T. Raymond D. W. Huling R. L. Shick E. C. Wagner W. E. Willard

1982-01-01

356

A PDMS lipseal for hydraulic and pneumatic microactuators  

Microsoft Academic Search

Recent publications show that hydraulic and pneumatic microactuators offer superior power and force densities at the microscale. The main technological barrier for the development of these actuators is the lack of microseal technologies. These seals must prevent the driving fluid leaking to the outside world without introducing friction. This paper presents a method to fabricate miniature lipseals in batch quantities.

Michaël DeVolder; Frederik Ceyssens; Dominiek Reynaerts; Robert Puers

2007-01-01

357

Development of a miniaturised hydraulic actuation system for artificial hands  

Microsoft Academic Search

This article will present a powerful miniaturised hydraulic system of compact design that is used for the actuation of artificial hands. This system was developed as an alternative to today's commonly used electromechanical prosthetic actuation systems. System components and hand prototypes reflect many years of experience of our laboratory in rehabilitation medicine, CAD design and prototyping, mechanical engineering, electronic construction,

A. Kargov; T. Werner; C. Pylatiuk; S. Schulz

2008-01-01

358

Piezoelectric hydraulic hybrid actuator for a potential smart rotor application  

Microsoft Academic Search

A piezoelectric hydraulic hybrid actuator is proposed as a potential actuator for a trailing edge flap on a smart rotor. Piezoceramics are very attractive for the smart rotor concept due to their high energy density and electro-mechanical coupling. To optimally design systems based on piezoceramic actuators and sensors, accurate prediction of their response and power consumption is necessary. However, at

Jayant Sirohi

2002-01-01

359

Thermal-hydraulic investigations on a pilot liquid metal target  

Microsoft Academic Search

Accelerator Driven Systems (ADS) promise to play an important role in nuclear power future due to their ability to enhance both the neutronics of reactors as well as safety physics. The target where neutrons are generated by a proton beam is one of the most important units of such a system. To achieve high thermal-hydraulic performance, different target concepts have

X Cheng; I Slessarev

2000-01-01

360

A hydraulic absorber for wideband vibration reduction in ship hulls  

Microsoft Academic Search

A vibration reduction of ship hulls by an active absorber system is proposed. In the scheme, a tuned mass is moved according to the hull vibration as measured by a multi-mode sensing system in order to generate a suitable active force for vibration reduction of hull girder. In order to supply the large amount of required power, a hydraulic servo

W. J. Hsueh; Y. J. Lee

1994-01-01

361

48 CFR 852.214-73 - Alternate packaging and packing.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 false Alternate packaging and packing. 852.214-73 Section...Clauses 852.214-73 Alternate packaging and packing. As prescribed in 814...the following provision: Alternate Packaging and Packing (JAN 2008) The...

2011-10-01

362

48 CFR 552.211-75 - Preservation, Packaging and Packing.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Preservation, Packaging and Packing. 552.211-75 Section...Clauses 552.211-75 Preservation, Packaging and Packing. As prescribed in 511...the following clause: Preservation, Packaging, and Packing (FEB 1996)...

2011-10-01

363

48 CFR 211.272 - Alternate preservation, packaging, and packing.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Alternate preservation, packaging, and packing. 211.272 Section... 211.272 Alternate preservation, packaging, and packing. Use the provision at 252.211-7004, Alternate Preservation, Packaging, and Packing, in solicitations...

2012-10-01

364

48 CFR 852.214-73 - Alternate packaging and packing.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 false Alternate packaging and packing. 852.214-73 Section...Clauses 852.214-73 Alternate packaging and packing. As prescribed in 814...the following provision: Alternate Packaging and Packing (JAN 2008) The...

2012-10-01

365

48 CFR 552.211-75 - Preservation, Packaging and Packing.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Preservation, Packaging and Packing. 552.211-75 Section...Clauses 552.211-75 Preservation, Packaging and Packing. As prescribed in 511...the following clause: Preservation, Packaging, and Packing (FEB 1996)...

2012-10-01

366

Flooding Characteristics of Packed Columns with High Efficiency.  

National Technical Information Service (NTIS)

Flooding characteristics of four high efficiency column packings, including Scientific Development Co. (SDC) protruded stainless distillation packing, Norton stainless pall rings, Podbielniak bronze Helipak, and Goodloe stainless wire mesh packing were de...

W. M. Choi R. C. Michel J. L. P. Varlet

1976-01-01

367

Operating experience on scrubbers with plane-parallel metal gauze packings  

SciTech Connect

Longterm operation of the scrubber with plane-parallel gauze packing has shown that its performance greatly exceeds that of the scrubber with chord packing (diameter 3 m, height 22 m). Tests on both types of scrubber under various conditions have established that they extract approximately the same proportions of benzol hydrocarbons. However, the low hydraulic resistance of the scrubber with plane-parallel packing lowers the costs of transporting the coke-oven gas. Both types of scrubbers can be purged with live steam when their resistance becomes excessively high. Since the wash-oil now in use is a heavier product (the proportion of fractions boiling in the range 235 to 270/sup 0/C has been reduced to 40 to 45%) with a higher proportion of anthracene fractions, there is a risk during the winter months of anthracene crystals clogging the scrubber packings (particularly in the last scrubber in the wash-oil cycle). Purging with live steam followed by washing with hot oil is a very effective method of removing these deposits; this procedure is all the more effective with the new type of scrubber because there is only a small area on which deposits of any nature can accumulate. Another advantage of the scrubber with plane-parallel packing is the ease with which existing scrubbers can be converted; moreover the maintenance costs are reduced. In conclusion, it can be noted that the standardized costs of operating scrubbers with timber chord and plane-parallel gauze packings at the Dneprodzerzhinsk C and CW are 18,146 and 12,545 rubles, respectively.

Pustovoit, M.I.; Yakushenko, A.K.

1981-01-01

368

Tomographic analysis of jammed ellipsoid packings  

NASA Astrophysics Data System (ADS)

Disordered packings of ellipsoidal particles are an important model for disordered granular matter. Here we report a way to determine the average contact number of ellipsoid packings from tomographic analysis. Tomographic images of jammed ellipsoid packings prepared by vertical shaking of loose configurations are recorded and the positions and orientations of the ellipsoids are reconstructed. The average contact number can be extracted from a contact number scaling (CNS) function. The size of the particles, that may vary due to production inaccuracies, can also be determined by this method.

Schaller, Fabian M.; Neudecker, Max; Saadatfar, Mohammad; Delaney, Gary; Mecke, Klaus; Schröder-Turk, Gerd E.; Schröter, Matthias

2013-06-01

369

DEM simulation of experimental dense granular packing  

NASA Astrophysics Data System (ADS)

In this study we present numerical analysis performed on the experimental results of sphere packings of mono-sized hard sphere whose packing fraction spans across a wide range of 0.59packings. Numerical analysis performed on thr data provides the first experimental proofs of how densification affects local order parameters. Furthermore by combining Discrete Element Method (DEM) and the experimental results from XCT, we investigate how the intergranular forces change with the onset of crystallization.

Hanifpour, Maryam; Francois, Nicolas; Allaei, Mehdi Vaez; Saadatfar, Mohammad

2013-06-01

370

Improved Taxation Rate for Bin Packing Games  

NASA Astrophysics Data System (ADS)

A cooperative bin packing game is a N-person game, where the player set N consists of k bins of capacity 1 each and n items of sizes a 1, ? ,a n . The value of a coalition of players is defined to be the maximum total size of items in the coalition that can be packed into the bins of the coalition. We present an alternative proof for the non-emptiness of the 1/3-core for all bin packing games and show how to improve this bound ?= 1/3 (slightly). We conjecture that the true best possible value is ?= 1/7.

Kern, Walter; Qiu, Xian

371

Hydraulic tests of emergency cooling system: L-Area  

SciTech Connect

The delay in L-Area startup provided an opportunity to obtain valuable data on the Emergency Cooling System (ECS) which will permit reactor operation at the highest safe power level. ECS flow is a major input to the FLOOD code which calculates reactor ECS power limits. The FLOOD code assesses the effectiveness of the ECS cooling capacity by modeling the core and plenum hydraulics under accident conditions. Presently, reactor power is not limited by the ECS cooling capacity (power limit). However, the manual calculations of ECS flows had been recently updated to include piping changes (debris strainer, valve changes, pressure release systems) and update fitting losses. Both updates resulted in reduced calculated ECS flows. Upon completion of the current program to update, validate, and document, reactor power may be limited under certain situations by ECS cooling capacity for some present reactor charge designs. A series of special hydraulic tests (Reference 1, 3) were conducted in L-Area using all sources of emergency coolant including the ECS pumps (Reference 2). The tests provided empirical hydraulic data on the ECS piping. These data will be used in computer models of the system as well as manual calculations of ECS flows. The improved modeling and accuracy of the flow calculations will permit reactor operation at the highest safe power level with respect to an ECS power limit.

Hinton, J H

1988-01-01

372

Automated hydraulic tensor for Total Knee Arthroplasty.  

PubMed

To obtain a long lifespan of knee prosthesis, it is necessary to restore the alignment of the lower limb. In some cases of severe arthrosis, the ligament envelope of the joint may be deformed, inducing an asymmetric laxity once the lower limb is realigned. Because there is not yet unanimity regarding how to optimally measure or implement soft tissue balance, we provide a means to acquire a variety of measurements. In traditional surgery, the surgeon sometimes uses a "tensor", which acts like a forceps. This system was redesigned, instrumented, actuated, and integrated into a navigation system for orthopaedic surgery. Improving the perception of the surgeon, it helps him to address the ligament balancing problem. Our first prototype has been tested on sawbones before being validated in an experiment on two cadavers. In our first attempt, the surgeon was able to assess soft tissue balance but judged the device not powerful enough, which led us to develop a new more powerful hydraulic system. In this paper, we present our approach and the first results of the new hydraulic tensor which is currently in an integration process. PMID:17518405

Marmignon, C; Leimnei, A; Lavallée, S; Cinquin, P

2005-12-01

373

Parametric Studies on the Load-Deflection Characteristics of Hydraulic Snubbers.  

National Technical Information Service (NTIS)

Hydraulic snubbers are extensively used in the nuclear power industry for supporting high energy piping systems subjected to dynamic loadings. These devices allow the piping system to displace freely under slowly applied loads, but lock up under sudden ex...

M. Subudhi J. B. P. Curreri M. Hartzman

1984-01-01

374

Hand-Held Hydraulic Rock Drill and Seafloor Fasteners for Use by Divers.  

National Technical Information Service (NTIS)

Underwater construction operations require an improved diver-operable rock drill and efficient and reliable seafloor rock fasteners. An experimental hydraulically powered rock drill was fabricated from commercially available components. The results from t...

R. L. Brackett A. M. Parisi

1975-01-01

375

Power.  

ERIC Educational Resources Information Center

|This issue addresses advantages and disadvantages of having power. Includes Web sites, CD-ROMs and software, videos, books, and additional resources with suggested age levels and disciplines as well as ideas for appropriate related activities. Sidebars discuss the power of the pen, the power of peace, and the power of the media. (LRW)|

Online-Offline, 1999

1999-01-01

376

Groundwater well with reactive filter pack  

DOEpatents

A method and apparatus are disclosed for the remediation of contaminated soil and ground water wherein a reactive pack material is added to the annular fill material utilized in standard well construction techniques. 3 figs.

Gilmore, T.J.; Holdren, G.R. Jr.; Kaplan, D.I.

1998-09-08

377

Groundwater well with reactive filter pack  

DOEpatents

A method and apparatus for the remediation of contaminated soil and ground water wherein a reactive pack material is added to the annular fill material utilized in standard well construction techniques.

Gilmore, Tyler J. (Pasco, WA); Holdren, Jr., George R. (Kennewick, WA); Kaplan, Daniel I. (Richland, WA)

1998-01-01

378

Fixed Packed Bed Reactors in Reduced Gravity.  

National Technical Information Service (NTIS)

We present experimental data on flow pattern transitions, pressure drop and flow characteristics for cocurrent gas-liquid flow through packed columns in microgravity. The flow pattern transition data indicates that the pulse flow regime exists over a wide...

B. J. Motil M. J. McCready V. Balakotaiah Y. Kamotani

2004-01-01

379

Consequence of Body Packing of Illicit Drugs  

Microsoft Academic Search

Background: During the last decade, increased rates of drug traffic have led the smugglers to use various methods. One of these methods of illicit drug smuggling is body packing. Smuggling by intra-abdominal concealment is called \\

Hossein Hassanian-Moghaddam

380

Laboratory Evaluation of Australian Ration Packs.  

National Technical Information Service (NTIS)

Results of analyses of ration pack items of the 1975/76 packaging programme are presented. Energy values are reported in Kilojoules. Some of the rations have become nutritionally unbalanced, particularly with respect to vitamin C and protein content. Tota...

C. H. Forbes-Ewan

1978-01-01

381

Design Packing to Safely Mail Raw Spaghetti  

NSDL National Science Digital Library

Students use their creative skills to determine a way to safely mail raw (dry, uncooked) spaghetti using only the provided materials. To test the packing designs, the spaghetti is mailed through the postal system and evaluated after delivery.

Center For Engineering Educational Outreach

382

A Versatile, Automatic Chromatographic Column Packing Device  

ERIC Educational Resources Information Center

|Describes an inexpensive apparatus for packing liquid and gas chromatographic columns of high efficiency. Consists of stainless steel support struts, an Automat Getriebmotor, and an associated three-pulley system capable of 10, 30, and 300 rpm. (MLH)|

Barry, Eugene F.; And Others

1977-01-01

383

Recall of Blood-Pack Unit  

Center for Biologics Evaluation and Research (CBER)

... Fenwal identified an assembly issue with the 4R3459 Blood-Pack Unit in which the satellite bag used for the storage of platelets was PL146 instead ... More results from www.fda.gov/biologicsbloodvaccines/safetyavailability/recalls

384

Densification of the packing structure under vibrations  

NASA Astrophysics Data System (ADS)

Two packing structures with the maximum packing densities of 0.64 and 0.74 for the amorphous state and crystalline state, respectively, were numerically reproduced in the packing densification of equal spheres subjected to onedimensional and three-dimensional vibrations using the discrete element method (DEM), and the results were physically validated. These two packing structures were analyzed in terms of coordination number (CN), radial distribution function (RDF), angular distribution function (ADF), and pore size distribution (Voronoi/Delaunay tessellation). It is shown that CN distributions have the peak values of 7 and 12 for the amorphous state and crystalline state, respectively. RDF and ADF distributions show isolated peaks and orientation preferences for the crystalline state, indicating the long range and angle correlation among particles commonly observed in the crystalline state. Voronoi/Delaunay tessellation also shows smaller and narrower pore size distribution for the crystalline state.

An, Xi-zhong

2013-05-01

385

Packing-limited growth of irregular objects  

Microsoft Academic Search

We study growth limited by packing for irregular objects in two dimensions.\\u000aWe generate packings by seeding objects randomly in time and space and allowing\\u000aeach object to grow until it collides with another object. The objects we\\u000aconsider allow us to investigate the separate effects of anisotropy and\\u000anon-unit aspect ratio. By means of a connection to the decay

Peter Sheridan Dodds; Joshua S. Weitz

2003-01-01

386

Adaptivity and approximation for stochastic packing problems  

Microsoft Academic Search

We study stochastic variants of Packing Integer Programs (PIP) --- the problems of finding a maximum-value 0\\/1 vector x satisfying Ax ? b, with A and b nonnegative. Many combinatorial problems belong to this broad class, including the knapsack problem, maximum clique, stable set, matching, hypergraph matching (a.k.a. set packing), b-matching, and others. PIP can also be seen as a

Brian C. Dean; Michel X. Goemans; Jan Vondrák

2005-01-01

387

Estimating Unsaturated Hydraulic Conductivity: Study the Effect of Tortuosity Factor  

NASA Astrophysics Data System (ADS)

Unsaturated soil hydraulic conductivity is one of the key soil hydraulic properties that, in one hand, is widely used in the studies of water and solute transport in soils, and on the other hand its direct measurement is time consuming and expensive. In this research, in order to study tortuosity factor (l) in the Burdine-Brooks-Corey (BBC hereafter), 59 soil samples from the GRIZZLY database were used. Using a sensitivity analysis, sensitive parameters of this model were determined. To study tortuosity factor, its different values e.g. 2, 1, 0.5, 0, -0.5, -1 and -2 were used in the estimation of unsaturated hydraulic conductivity. The results of sensitivity analysis showed that BBC model is more sensitive to the saturated water content and pore size distribution index. Whereas, the BBC model is less sensitive to tortuosity factor and saturated hydraulic conductivity. The calculated statistical parameter SAE in estimation of unsaturated hydraulic conductivity indicated that the BBC model error with l=2 is less than other values. The results also showed that tortuosity factor is linearly correlated with the power of BCC model with goodness of fit R2=0.96. Based on this approach, tortuosity factor was removed from BCC model, and a new empirical equation was developed to estimate unsaturated hydraulic conductivity. This model was verified using 33 samples of the UNSODA database. The results showed that the developed empirical equation estimated unsaturated hydraulic conductivity better than BCC model in which tortuosity factor was assumed to be equal to 2. Acknowledgments The authors are grateful to Drs. M.Th. van Genuchten and R. Haverkamp for providing the UNSODA and GRIZZLY data sets.

Ghanbarian-Alavijeh, Behzad; Abbasi, Fariborz

2010-05-01

388

How do trays and packings stack up  

SciTech Connect

Chemical engineers often must grapple with choosing the most-appropriate internals for fractionators. The wide variety of trays, as well as structured and random packings makes the selection difficult. Even more of a problem, however, can be determining which of the three types of hardware is most appropriate in the first place. A detailed list of the strengths and weaknesses of each hardware type is available elsewhere. Considerations include pressure drop, sensitivity to fouling, liquid holdup, ease of handling high (or low) liquid rates, resistance to oxidation, and cost. Prominent among these considerations are capacity and separation differences. Capacity and separation differences between tray and packed towers are due to four main factors: (1) differences between the capacity and efficiency of an optimal tray and an optimal packed tower design; (2) deviations from optimal design of trays, packings, and other tower internals; (3) unique system characteristics and special design features; and (4) capacity and separation gains due to the lower pressure drop of packing. This article focuses on the first factor, that is, differences between the capacity and efficiency of an optimal tray and an optimal packed tower design, because the other three factors must be analyzed on a case-by-case basis.

Kister, H.Z.; Larson, K.F.; Yanagi, T. (Brown Root Petroleum and Chemicals, Alhambra, CA (United States))

1994-02-01

389

Application study of magnetic fluid seal in hydraulic turbine  

NASA Astrophysics Data System (ADS)

The waterpower resources of our country are abundant, and the hydroelectric power is developed, but at present the main shaft sealing device of hydraulic turbine is easy to wear and tear and the leakage is great. The magnetic fluid seal has the advantages of no contact, no wear, self-healing, long life and so on. In this paper, the magnetic fluid seal would be used in the main shaft of hydraulic turbine, the sealing structure was built the model, meshed the geometry, applied loads and solved by using MULTIPHYSICS in ANSYS software, the influence of the various sealing structural parameters such as tooth width, height, slot width, sealing gap on the sealing property were analyzed, the magnetic fluid sealing device suitable for large-diameter shaft and sealing water was designed, the sealing problem of the hydraulic turbine main shaft was solved effectively which will bring huge economic benefits.

Yu, Z. Y.; Zhang, W.

2012-11-01

390

A study to determine the benefits of bilateral versus unilateral nasal packing with Rapid Rhino(®) packs.  

PubMed

There is little evidence to suggest that bilateral nasal packing increases intra-nasal pressures compared to a single pack (or is well tolerated) for uncontrolled unilateral epistaxis, but it is often performed and justified on those grounds. 15 volunteers were recruited according to strict criteria. Rapid Rhino(®) 5.5 cm anterior packs were inserted bilaterally following topical nasal preparation with co-phenylcaine. The first pack was inflated to a pre-determined pressure. The contralateral pack was inflated to match, and any intra-nasal pressure change on the first side was measured. The subject's level of discomfort was scored on a visual analogue scale. This procedure was repeated at incremental pressures. Higher ipsilateral intra-nasal pressures are achieved when additional contralateral nasal packs are inflated. This change in ipsilateral intra-nasal pressure is greater at higher total inflation pressures. At higher pressures, the subjects reported lower mean pain scores when bilateral packs were used compared to unilateral. This effect was only statistically significant at intra-nasal pressures of 140 mmHg and above (Wilcoxon Signed-Rank test, p < 0.02). It is possible to increase the ipsilateral nasal cavity pressure by inserting a contralateral nasal pack. Although this extra pressure may be enough to tamponade further venous bleeding without significantly increasing a subject's discomfort, the high levels of pack pressure required, make this unlikely to be of significant use in the clinical setting. PMID:23765062

Hettige, Roland; Mackeith, Sam; Falzon, Adam; Draper, Mark

2013-06-14

391

Evaluation of lithium-ion synergetic battery pack as battery charger  

SciTech Connect

A new battery configuration technique and accompanying control circuitry, termed a Synergetic Battery Pack (SBP), is designed to work with Lithium batteries, and can be used as both an inverter for an electric vehicle AC induction motor drive and a battery charger. In this paper, the authors compare the performance of the Synergetic Battery Pack as a battery charger with several simple conventional battery charging circuits via computer simulation. The factors of comparison were power factor, harmonic distortion, and circuit efficiency. The simulations showed that the SBP is superior to the conventional charging circuits since the power factor is unity and harmonic distortion is negligible.

Davis, A.; Salameh, Z.M.; Eaves, S.S.

1999-09-01

392

Fluid shear influences on the performance of hydraulic flocculation systems.  

PubMed

Gravity driven hydraulic flocculators that operate in the absence of reliable electric power are better suited to meet the water treatment needs of green communities, resource-poor communities, and developing countries than conventional mechanical flocculators. However, current understanding regarding the proper design and operation of hydraulic flocculation systems is insufficient. Of particular interest is the optimal fluid shear level needed to produce low turbidity water. A hydraulic tube flocculator was used to study how fluid shear levels affect the settling properties of a flocculated alum-kaolin suspension. A Flocculation Residual Turbidity Analyzer (FReTA) was used to quantitatively compare the sedimentation velocity distributions and the post-sedimentation residual turbidities of the flocculated suspensions to see how they were affected by varying fluid shear, G, and hydraulic residence time, ?, while holding collision potential, G?, constant. Results show that floc breakup occurred at all velocity gradients evaluated. High floc settling velocities were correlated with low residual turbidities, both of which were optimized at low fluid shear levels and long fluid residence times. This study shows that, for hydraulic flocculation systems under the conditions described in this paper, low turbidity water is produced when fluid shear is kept at a minimum. Use of the product G? for design of laminar flow tube flocculators is insufficient if residual turbidity is used as the metric for performance. At any G? within the range tested in this study, best performance is obtained when G is small and ? is long. PMID:21880341

Tse, Ian C; Swetland, Karen; Weber-Shirk, Monroe L; Lion, Leonard W

2011-08-23

393

Method for directional hydraulic fracturing  

DOEpatents

A method for directional hydraulic fracturing using borehole seals to confine pressurized fluid in planar permeable regions, comprising: placing a sealant in the hole of a structure selected from geologic or cemented formations to fill the space between a permeable planar component and the geologic or cemented formation in the vicinity of the permeable planar component; making a hydraulic connection between the permeable planar component and a pump; permitting the sealant to cure and thereby provide both mechanical and hydraulic confinement to the permeable planar component; and pumping a fluid from the pump into the permeable planar component to internally pressurize the permeable planar component to initiate a fracture in the formation, the fracture being disposed in the same orientation as the permeable planar component.

Swanson, David E. (West St. Paul, MN); Daly, Daniel W. (Crystal, MN)

1994-01-01

394

Hydraulic processes on alluvial fans  

SciTech Connect

Alluvial fans are among the most prominent landscape features in the American Southwest and throughout the semi-arid and arid regions of the world. The importance of developing a qualitative and quantitative understanding of the hydraulic processes which formed, and which continue to modify, these features derives from their rapid and significant development over the past four decades. As unplanned urban sprawl moved from valley floors onto alluvial fans, the serious damage incurred from infrequent flow events has dramatically increased. This book presents a discussion of our current and rapidly expanding knowledge of hydraulic processes on alluvial fans. It addresses the subject from a multidisciplinary viewpoint, acquainting the reader with geological principles pertinent to the analysis of hydraulic processes on alluvial fans.

French, R.H.

1987-01-01

395

Packing in molten globules and native states.  

PubMed

Close packing of hydrophobic residues in the protein interior is an important determinant of protein stability. Cavities introduced by large to small substitutions are known to destabilize proteins. Conversely, native states of proteins and protein fragments can be stabilized by filling in existing cavities. Molten globules (MGs) were initially used to describe a state of protein which has well-defined secondary structure but little or no tertiary packing. Subsequent studies have shown that MGs do have some degree of native-like topology and specific packing. Wet molten globules (WMGs) with hydrated cores and considerably decreased packing relative to the native state have been studied extensively. Recently there has been renewed interest in identification and characterization of dry molten globules (DMGs). These are slightly expanded forms of the native state which show increased conformational flexibility, native-like main-chain hydrogen bonding and dry interiors. The generality of occurrence of DMGs during protein unfolding and the extent and nature of packing in DMGs remain to be elucidated. Packing interactions in native proteins and MGs can be probed through mutations. Next generation sequencing technologies make it possible to determine relative populations of mutants in a large pool. When this is coupled to phenotypic screens or cell-surface display, it becomes possible to rapidly examine large panels of single-site or multi-site mutants. From such studies, residue specific contributions to protein stability and function can be estimated in a highly parallelized fashion. This complements conventional biophysical methods for characterization of packing in native states and molten globules. PMID:23270864

Bhattacharyya, Sanchari; Varadarajan, Raghavan

2012-12-25

396

A novel structured catalyst packing for catalytic distillation of ETBE  

Microsoft Academic Search

Catalytic distillation can offer significant reduction of capital costs in G\\/L\\/S processes that are equilibrium limited. As an alternative to existing catalytic distillation packings, containing bales or pockets of catalyst stacked in (a section of) the distillation column, a novel structured catalyst packing is proposed. The novel packing consists of a common structured distillation packing, on which a binderless film

O. L. Oudshoorn; M. Janissen; W. E. J. van Kooten; J. C. Jansen; H. van Bekkum; C. M. van den Bleek; H. P. A. Calis

1999-01-01

397

Random packings of spheres and spherocylinders simulated by mechanical contraction  

Microsoft Academic Search

We introduce a simulation technique for creating dense random packings of hard particles. The technique is particularly suited to handle particles of different shapes. Dense amorphous packings of spheres have been formed, which are consistent with the existing work on random sphere packings. Packings of spherocylinders have also been simulated out to the large aspect ratio of alpha=160.0. Our method

S. R. Williams; A. P. Philipse

2003-01-01

398

Modeling biooxidation of iron in packed-bed reactor  

SciTech Connect

Acid mine drainage (AMD) from active and abandoned mines continues to be an important source of water pollution in the US and around the world. AMD typically has high levels of acidity, sulfate, and metals. A model based on Monod kinetics and originally developed for use with rotating biological contactors was modified for use with a packed-bed column reactor. The reactor was filled with expanded polystyrene beads to immobilize chemolithotrophic bacteria and fed up to 570 mg L{sup {minus}1} ferrous iron [Fe(II)] in simulated acid mine drainage. A tracer study indicated changing behavior as a function of hydraulic residence time (HRT), with a transition from complete mix flow behavior to plug flow behavior as HRT decreased. The Fe(II) oxidation efficiency exceeded 95% until the HRT was reduced below 0.5 h. The reactor performance could be predicted with the model using estimates from the literature for {cflx u} and Y. The experimentally determined half-saturation constant K{sub s} was found to range from 5 to 12 mg L{sup {minus}1}. The maximum volumetric capacity constant R{sub max} was estimated to be {approximately}360 mg Fe(II)h{sup {minus}1} L{sup {minus}1} beads under complete mix flow conditions but appeared to be as high as 724 mg Fe(II)h{sup {minus}1} L{sup {minus}1} beads as conditions approached plug flow at short HRTs.

Diz, H.R. [Gannon Univ., Erie, PA (United States). Dept. of Environmental Science and Engineering; Novak, J.T. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States)

1999-02-01

399

Electrokinetic high pressure hydraulic system  

SciTech Connect

A compact high pressure hydraulic system having no moving parts for converting electric potential to hydraulic force and for manipulating fluids. Electro-osmotic flow is used to provide a valve and means to compress a fluid or gas in a capillary-based system. By electro-osmotically moving an electrolyte between a first position opening communication between a fluid inlet and outlet and a second position closing communication between the fluid inlet and outlet the system can be configured as a valve. The system can also be used to generate forces as large as 2500 psi that can be used to compress a fluid, either a liquid or a gas.

Paul, P.H.; Rakestraw, D.J.

2000-01-11

400

Numerical simulation of hydraulic transients  

NASA Astrophysics Data System (ADS)

A numerical method suitable for the analysis of hydraulic transients in one-dimensional pipelines as well as some applications of the method are presented in this thesis. In the present method one-dimensional flow equations are solved in a characteristic form using a finite difference technique. A nonequilibrium two-phase flow model is used, which makes it possible to analyze the effect of vaporization. The motion of the pipe-wall, which is important in some types of hydraulic transients, can be taken into account approximately. The main application of the method has been the piping of nuclear reactors.

Siikonen, T.

401

Measured Black Carbon Deposition on the Sierra Nevada Snow Pack and Implication for Snow Pack Retreat  

Microsoft Academic Search

Modeling studies show that the darkening of snow and ice by black carbon deposition is a major factor for the rapid disappearance of arctic sea ice, mountain glaciers and snow packs. This study provides one of the first direct measurements for the efficient removal of black carbon from the atmosphere by snow and its subsequent deposition to the snow packs

O. L. Hadley; C. E. Corrigan; T. W. Kirchstetter; S. S. Cliff; V. Ramanathan

2010-01-01

402

Secondary power systems  

SciTech Connect

In aeronautical engineering secondary power systems have long played second fiddle to the airframe, the engine, and indeed, the avionics. This collection of papers is thus timely, and its publication by the Institution of Mechanical Engineers appropriate, as secondary power systems in modern aircraft present challenging mechanical engineering problems. In military aircraft demands for electrical and hydraulic power and high pressure air have grown over the past two decades. To these basic needs are added requirements for emergency power, ground power, and independent engine starting. Additionally increased reliability and maintainability is demanded from all secondary power systems. Complete contents: What is a secondary power system. Modern technology secondary power systems for next generation military aircraft; Integrated power units; Secondary power system gearbox; Starting the system - air turbine starters; Auxiliary and emergency power system; Secondary hydraulic power generation; Advanced technology electrical power generation equipment.

Not Available

1985-01-01

403

Study of the Unequal Spheres Packing Problem:  

NASA Astrophysics Data System (ADS)

We employ the Monte Carlo method to study a constrained optimization problem — packing hard spheres with unequal radii (r2 > r1) into a 3D bounded region and discuss its connection with the Gamma Knife radiosurgery treatment planning. Selection of the best fit solution is based on the Boltzmann factor, e-?E/T, which allows us to search for the global optimal solution. As an illustration we determined the least number (?15) of packed spheres that will occupy the largest volume for three different hypothetical tumor sizes (4115, 10 000 and 36 000 voxels). For the bounded regions and the sizes of the packed spheres that we studied here, the optimal volume packing ratio ranges from 41.3 to 48.7%. From our study, using a lower r2/r1 ratio is more desirable due to the ?15 radiation shots constraint. The optimal volume packing ratio can be obtained within a relative short CPU computing time and could provide a good starting point for the radiosurgery treatment planning.

Li, S. P.; Ng, Ka-Lok

404

Vector Bin Packing with Multiple-Choice  

NASA Astrophysics Data System (ADS)

We consider a variant of bin packing called multiple-choice vector bin packing. In this problem we are given a set of n items, where each item can be selected in one of several D-dimensional incarnations. We are also given T bin types, each with its own cost and D-dimensional size. Our goal is to pack the items in a set of bins of minimum overall cost. The problem is motivated by scheduling in networks with guaranteed quality of service (QoS), but due to its general formulation it has many other applications as well. We present an approximation algorithm that is guaranteed to produce a solution whose cost is about ln D times the optimum. For the running time to be polynomial we require D = O(1) and T = O(logn). This extends previous results for vector bin packing, in which each item has a single incarnation and there is only one bin type. To obtain our result we also present a PTAS for the multiple-choice version of multidimensional knapsack, where we are given only one bin and the goal is to pack a maximum weight set of (incarnations of) items in that bin.

Patt-Shamir, Boaz; Rawitz, Dror

405

Rio Blanco massive hydraulic fracture: project definition  

SciTech Connect

A recent Federal Power Commission feasibility study assessed the possibility of economically producing gas from three Rocky Mountain basins. These basins have potentially productive horizons 2,000 to 4,000 feet thick containing an estimated total of 600 trillion cubic feet of gas in place. However, the producing sands are of such low permeability and heterogeneity that conventional methods have failed to develop these basins economically. The Natural Gas Technology Task Force, responsible for preparing the referenced feasibility study, determined that, if effective well stimulation methods for these basins can be developed, it might be possible to recover 40 to 50 percent of the gas in place. The Task Force pointed out two possible underground fracturing methods: Nuclear explosive fracturing, and massive hydraulic fracturing. They argued that once technical viability has been demonstrated, and with adequate economic incentives, there should be no reason why one or even both of these approaches could not be employed, thus making a major contribution toward correcting the energy deficiency of the Nation. A joint Government-industry demonstration program has been proposed to test the relative effectiveness of massive hydraulic fracturing of the same formation and producing horizons that were stimulated by the Rio Blanco nuclear project.

Not Available

1976-01-01

406

Hydraulic jet pumping in a remote location  

SciTech Connect

Hydraulic jet pumping equipment was installed in six Sembakung field (N.E. Kalimantan) wells by Atlantic Richfield Indonesia Inc., for Pertamina during 1983, and this article presents the experience acquired in the process of installing and operating this type of artificial-lift equipment in a remote location. Characteristics of the wells and equipment are reviewed, and possible future installations in similar circumstances are discussed. Sembakung oil field, discovered in late 1975, contained 17 wells after complete development. By 1983, some were flowing weakly and several zones were dead, indicating the need for some form of artificial lift. The choice of artificial lift methods was limited by the lack of gas-lift gas, absence of a field-wide power distribution system, unavailability of a rod pumping well servicing unit, and lack of roads in the marshy environment. Thus, hydraulic (free-type) jet pumping was selected as the optimum technique. Jet pumps were installed in six of 17 wells in the field at the end of 1983. Downhole equipment was installed using a heli-rig, and all surface equipment was delivered to location using helicopters. Since startup, some operating problems occurred, but they have all been resolved. Well pumping rates range from 340 to 650 bpd gross, with 0 to 50% BSandW. The jet-pumped wells produced satisfactorily through July 1984, at which time operations were turned over to Pertamina Unit IV at the conclusion of the contractual term.

Tjondrodiputro, B.; Gaul, R.B.; Gower, G.H.

1986-12-01

407

The power of transient piezometric head data in inverse modeling: An application of the localized normal-score EnKF with covariance inflation in a heterogenous bimodal hydraulic conductivity field  

NASA Astrophysics Data System (ADS)

The localized normal-score ensemble Kalman filter (NS-EnKF) coupled with covariance inflation is used to characterize the spatial variability of a channelized bimodal hydraulic conductivity field, for which the only existing prior information about conductivity is its univariate marginal distribution. We demonstrate that we can retrieve the main patterns of the reference field by assimilating a sufficient number of piezometric observations using the NS-EnKF. The possibility of characterizing the conductivity spatial variability using only piezometric head data shows the importance of accounting for these data in inverse modeling.

Xu, Teng; Jaime Gómez-Hernández, J.; Zhou, Haiyan; Li, Liangping

2013-04-01

408

46 CFR 28.880 - Hydraulic equipment.  

Code of Federal Regulations, 2012 CFR

...material in a hydraulic system must be suitable for use with the hydraulic fluid used and must be of such chemical and physical properties as to remain ductile at the lowest operating temperature likely to be encountered by the vessel....

2012-10-01

409

Hydraulic Sandfill in Deep Metal Mines.  

National Technical Information Service (NTIS)

The Bureau of Mines and industry (mining and private) have studied the placement of hydraulic sandfill in deep vein mines to identify existing problems and to develop techniques to strengthen the support characteristics of the sandfill. The hydraulic sand...

L. M. McNay D. R. Corson

1975-01-01

410

CRITICALITY CURVES FOR PLUTONIUM HYDRAULIC FLUID MIXTURES  

SciTech Connect

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

WITTEKIND WD

2007-10-03

411

Machine Construction Hydraulics: A Reference Manual.  

National Technical Information Service (NTIS)

The report presents the basic principles of the hydraulics of pipelines, the flow of fluid through capillary slits, and the theory of hydraulic impact in hydrosystems. The author examines the principles of the theory, design and calculation of pumps, hydr...

T. M. Bashta

1973-01-01

412

14 CFR 23.1435 - Hydraulic systems.  

Code of Federal Regulations, 2013 CFR

...Hydraulic systems. (a) Design. Each hydraulic system...exceed the safe limit above design operating pressure and to...occur. (4) The minimum design burst pressure must be 2...integral part of an engine or propeller system, or (2) The...

2013-01-01

413

Design of a smart material electro-hydraulic actuator with improved frequency bandwidth  

NASA Astrophysics Data System (ADS)

Smart material electro-hydraulic actuators utilize fluid rectification by one-way valves to convert the small, high-frequency, high-force motions of smart materials such as piezoelectrics and magnetostrictives into useful motions of a hydraulic cylinder. These actuators have potential to replace centralized hydraulic pumps and lines with lightweight, compact, power-by-wire systems. This paper presents the design and testing of an improved actuator system. To increase the frequency bandwidth of operation, a lumped-parameter model is developed and validated based on experimental study of a pump with a performance capacity of 18.4 W. The critical parameters for pump performance are identified and their effect on pump performance assessed. The geometry of the hydraulic manifold that integrates the smart material pump and the output hydraulic cylinder is found to be critical for determining the effective system bandwidth.

Larson, John P.; Dapino, Marcelo J.

2012-03-01

414

Hydraulic Circuit for Prevention of Inadvertent Weapon Launches.  

National Technical Information Service (NTIS)

A hydraulic circuit for prevention of inadvertent weapons launches in which a hydraulic firing valve provides hydraulic pressure to a backup select valve rather than the backup select valve receiving hydraulic pressure directly from a ship supply header. ...

M. T. Ansay

2006-01-01

415

Failure of a loose packing of grains  

NASA Astrophysics Data System (ADS)

One-sided repulsive interactions and history-dependent friction forces can cause the mechanics of real granular systems to deviate significantly from that of cohesive solids. Marked deviations from elastic behavior can be seen in the mechanical response and structure of sedimented loose packings of frictional spheres even for very delicate perturbations. In our experiments, particles' displacements are observed with 3D fluorescent imaging as a shear plane is displaced through the packing. As anticipated, we find the shear force is approximately linear with the displacement between discrete yielding events. However, even in this apparently linear region, structural aging continues to occur for the smallest displacements that we can apply. This suggests the inaccessibility of a reversible shear deformation regime in loose packings of granular material. We present a spatial characterization of the particle motion that distinguishes between these continuous instances of irreversibility and the larger discrete failure events.

Farrell, Greg; Menon, Narayanan

2012-02-01

416

Method for packed column separations and purifications  

SciTech Connect

The invention encompasses a method of packing and unpacking a column chamber. A mixture of a fluid and a matrix material are introduced through a column chamber inlet so that the matrix material is packed within a column chamber to form a packed column. The column chamber having the column chamber inlet or first port for receiving the mixture further has an outlet port and an actuator port. The outlet port is partially closed for capturing the matrix material and permitting the fluid to flow therepast by rotating relative one to the other of a rod placed in the actuator port. Further rotation relative one to the other of the rod and the column chamber opens the outlet and permits the matrix material and the fluid to flow therethrough thereby unpacking the matrix material from the column chamber.

Holman, David A. (Richland, WA); Bruckner-Lea, Cynthia J. (Richland, WA); Brockman, Fred J. (Kennewick, WA); Chandler, Darrell P. (Richland, WA)

2006-08-15

417

Creation of multiple sequential hydraulic fractures via hydraulic fracturing combined with controlled pulse fracturing  

Microsoft Academic Search

A method for creating multiple sequential hydraulic fractures via hydraulic fracturing combined with controlled pulse fracturing is described comprising: (a) creating more than two simultaneous multiple vertical radial fractures via a controlled pulse fracturing method; (b) applying thereafter hydraulic pressure to the formation in an amount sufficient to fracture; (c) maintaining the hydraulic pressure on the formation while pumping alternate

Uhri

1988-01-01

418

Tree Hydraulics: How Sap Rises  

ERIC Educational Resources Information Center

|Trees transport water from roots to crown--a height that can exceed 100 m. The physics of tree hydraulics can be conveyed with simple fluid dynamics based upon the Hagen-Poiseuille equation and Murray's law. Here the conduit structure is modelled as conical pipes and as branching pipes. The force required to lift sap is generated mostly by…

Denny, Mark

2012-01-01

419

The hydraulic limitation hypothesis revisited  

Microsoft Academic Search

We proposed the hydraulic limitation hypothesis (HLH) as a mechanism to explain universal patterns in tree height, and tree and stand biomass growth: height growth slows down as trees grow taller, maximum height is lower for trees of the same species on resource-poor sites and annual wood production declines after canopy closure for even-aged for- ests. Our review of 51

MICHAEL G. RYAN; NATHAN PHILLIPS; BARBARA J. BOND

2006-01-01

420

Development of Nonflammable Hydraulic Fluid.  

National Technical Information Service (NTIS)

The object of the study is the development of a waterbase hydraulic fluid which (1) yields a fire-resistent non-aqueous residue, (2) is compatible with materials of construction and sea-water contamination, (3) satisfactorily lubricates shipboard pumps, (...

K. R. Bunting A. M. Dobry E. A. Swakon P. C. Vienna L. W. Mixon

1964-01-01

421

Development of Nonflammable Hydraulic Fluid.  

National Technical Information Service (NTIS)

The object of the study is the development of a waterbase hydraulic fluid which (1) yields a fire-resistant non-aqueous residue, (2) is compatible with materials of construction and sea-water contamination, (3) satisfactorily lubricates shipboard pumps, (...

K. R. Bunting A. M. Dobry E. A. Swakon P. C. Vienna L. W. Mixon

1964-01-01

422

Development of Nonflammable Hydraulic Fluid.  

National Technical Information Service (NTIS)

The object of the study is the development of a waterbase hydraulic fluid which (1) yields a fire-resistant non-aqueous residue, (2) is compatible with materials of construction and sea-water contamination, (3) satisfactorily lubricates shipboard pumps, (...

K. R. Bunting A. M. Dobry E. A. Swakon P. C. Vienna L. W. Mixon

1965-01-01

423

Development of Nonflammable Hydraulic Fluid.  

National Technical Information Service (NTIS)

The object of the study was the development of a waterbase hydraulic fluid which (1) yields a fire-resistant non-aqueous residue, (2) is compatible with materials of construction and sea-water contamination, (3) satisfactorily lubricates shipboard pumps, ...

K. R. Bunting A. M. Dobry E. A. Swakon P. C. Vienna L. W. Mixon

1965-01-01

424

Development of Nonflammable Hydraulic Fluid.  

National Technical Information Service (NTIS)

The objective of the study is the development of a water-base hydraulic fluid which (1) yields a fireresistant non-aqueous residue, (2) is compatible with materials of construction and sea-water contamination, (3) satisfactorily lubricates shipboard pumps...

K. R. Bunting A. M. Dobry E. A. Swakon P. C. Vienna L. W. Mixon

1965-01-01

425

Development of Nonflammable Hydraulic Fluid.  

National Technical Information Service (NTIS)

The development of a water-base hydraulic fluid which (1) yields a fire-resistant non-aqueous residue, (2) is compatible with materials of construction and sea-water contamination, (3) satisfactorily lubricates shipboard pumps, (4) presents no unusual sto...

K. R. Bunting A. M. Dobry E. A. Swakon P. C. Vienna L. W. Mixon

1964-01-01

426

Hydraulic Fracture Containment in Sand  

Microsoft Academic Search

The mechanism of hydraulic fracturing in soft, high permeability material is considered fundamentally different from that in hard, low permeability rock, where a tensile fracture is created and conventional linear elastic fracture mechanics (LEFM) applies. The fracturing and associated modeling work is then a relatively new area. Particularly, the fracture containment in layered formations remains unknown. This research is aiming

Y. Dong

2010-01-01

427

Experiments in Hydraulic Rock Cutting.  

National Technical Information Service (NTIS)

A theory of hydraulic rock cutting was tested by conducting experiments on four different rocks in the laboratory. The tests involved directing a stationary high speed water jet of small diameter onto a moving rock target. The slot thus cut in the rock wa...

G. H. Hurlburt S. C. Crow P. V. Lade

1974-01-01

428

Reducing leaks in hydraulic systems  

SciTech Connect

This article examines the effect of hydraulic system leaks on energy efficiency and cost. The topics of the article include causes of leakage, external and internal leakage, safety hazards, simple seals and sealants for tapered pipe threads, maintaining, retrofitting, or reworking welded systems, and lowering leakage by reducing the number of fittings.

Simko, D.M. [Swagelok Co., Solon, OH (United States)

1995-07-10

429

Hydro Hydraulics - a disappearing art?  

Microsoft Academic Search

Over the past decade, there have been several instances where the performance of new hydro developments has been compromised by unsatisfactory operation of some component associated with the hydraulic design of the facility. This paper will outline the types of deficiencies encountered, and suggest some remedies. The incidents include - gravel entrainment at intakes; \\

J. L. Gordon

2007-01-01

430

Silent Variable Delivery Hydraulic Pump.  

National Technical Information Service (NTIS)

The hydraulic pump is used on a submarine. The apparatus includes a valve device in the form of a plate and a multi-cylinder, parallel piston pump. The pump includes a rotatable assembly comprised of a barrel body with a plurality of parallel cylinders, e...

A. Lehrer

1965-01-01

431

Introduction to Hydraulics. Instructor's Guide.  

ERIC Educational Resources Information Center

|This instructor's guide on hydraulics is part of a series of individualized instructional materials. The guide is provided to help the instructor make certain that each student gets the most benefit possible from both the student's manual and what he/she does on the job. Notes for the instructor contain suggestions on how the student should use…

Texas Univ., Austin. Extension Instruction and Materials Center.

432

Introduction to Hydraulics. Student's Manual.  

ERIC Educational Resources Information Center

|This manual on hydraulics is one of a series of individualized instructional materials for students. The manual is self-paced, but is designed to be used under the supervision of an instructor. The manual contains 10 assignments, each with all the information needed, a list of objectives that should be met, and exercise questions that can help in…

Texas Univ., Austin. Extension Instruction and Materials Center.

433

Hydraulic conductivity of rice roots  

Microsoft Academic Search

A pressure chamber and a root pressure probe technique have been used to measure hydraulic conductivities of rice roots (root Lpr per m 2 of root surface area). Young plants of two rice (Oryza sativa L.) varieties (an upland variety, cv. Azucena and a lowland variety, cv. IR64) were grown for 31-40 d in 12 h days with 500 mmol

Naoko Miyamoto; Ernst Steudle; Tadashi Hirasawa; Renee Lafitte

2001-01-01

434

Thermal hydraulic analysis of advanced Pb-Bi cooled NPP using natural circulation  

NASA Astrophysics Data System (ADS)

We present thermal hydraulic analysis for a low power advanced nuclear reactor cooled by lead-bismuth eutectic. In this work is to study the thermal hydraulic analysis of a low power SPINNOR (Small Power Reactor, Indonesia, No On-site Refuelling) reactor with 125 MWth which a design a core with very small volume and fuel column height, resulting in a negative coolant temperature coefficient and very low channel pressure drop. And also at full power the heat can be completely removed by natural circulation in the primary circuit, thus eliminating the needs for pumps.

Novitrian; Su'ud, Zaki; Waris, Abdul

2012-06-01

435

Study on the Key Image Processing Technology in the Inspection of Packing Quality for Small-Pack Cigarettes  

Microsoft Academic Search

Image processing is a key factor in the inspection of packing quality by machine vision. Targeting the inspection of packing quality for small-pack cigarettes in tobacco enterprises, this paper proposes a series of key image processing techniques: a fast algorithm for small-pack edge collecting based on fast Hough transformation, an online differentiating algorithm based on GLCM parameters, and packing-flaw detection

Hu Fang-xia; He xin; Niu Tian-gui

2007-01-01

436

Motor applications for hydraulic roll crushers  

Microsoft Academic Search

The hydraulic roll crusher (HRC) is a relative newcomer to the family of major cement producing machinery, which includes kilns, mills, and the like. Also, there are a variety of configurations in which the hydraulic roll crusher may be utilized. These two factors, among others, may sometimes make the proper selection and specification of drive motors for the hydraulic roll

G. R. Kotz; M. P. Regan

1994-01-01

437

Hiberarchy clustering fault diagnosis of hydraulic pump  

Microsoft Academic Search

Fault diagnosis is one of the key technologies of prognostic and health management system (PHM) of aircraft hydraulic system. Aiming at the strong coupling of various fault features of hydraulic pump when multiple faults occur simultaneously, a hiberarchy clustering fault diagnosis strategy was proposed, in which three level fault reasoning machine was adopted for five kinds of failures for hydraulic

Jun Du; Shaoping Wang

2010-01-01

438

Land Use Effects on Soil Hydraulic Properties  

Microsoft Academic Search

Tillage alters the pore structure and hydraulic properties of soils. Likewise, reestablishment of grass on cropland will, over time, produce changes in soil hydraulic properties that can influence the amount of plant available water. We conducted a study to characterize and compare soil hydraulic properties on adjacent native grassland, cropland, and Conservation Reserve Program (CRP) sites at three locations in

R. C. Schwartz; P. W. Unger; S. R. Evett

439

Hydraulic lift: a potentially important ecosystem process  

Microsoft Academic Search

Hydraulic lift is the process by which some deep-rooted plants take in water from lower soil layers and exude that water into upper, drier soil layers. Hydraulic lift is beneficial to the plant transporting the water, and may be an important water source for neighboring plants. Recent evidence shows that hydraulically lifted water can promote greater plant growth, and could

Jonathan L. Horton; Stephen C. Hart

1998-01-01

440

Hydraulic stud tensioning aids pump performance  

Microsoft Academic Search

This article considers the use of hydraulic stud tensioners on mud pump fluid ends. It contains tensioner testing and application. A typical problem involving a fluid end stud is presented to illustrate the use of hydraulic tensioning. Hydraulic stud tensioners give optimum preload reliability over traditional torque tensioning methods. Accurately controlling preload increases stud fatigue life and minimizes maintenance. At

1986-01-01

441

Packing Transitions in Nanosized Li Clusters  

NASA Astrophysics Data System (ADS)

Packing transitions in the lowest energy structures of Li clusters as a function of size have been identified via simulated annealing. For N<=21, the large p character of Li leads to unexpected ionic structures. At N~=25, a packing pattern based on interpenetrating 13-atom icosahedra and similar to that of Na and K appears. This pattern persists until at N=55, where another transition to a structure based on a Mackay icosahedron (MIC) occurs. For clusters of size 55 and 147, the optimized fcc structure representative of the bulk is still slightly higher in energy than the optimal MIC.

Sung, Ming-Wen; Kawai, Ryoichi; Weare, John H.

1994-12-01

442

Dense packing: surgical indications and technical considerations.  

PubMed

Dense packing is the philosophy of fitting more than 30 to 35 follicular unit grafts per square centimeter in one operation. The aim is to produce a more even, consistent, and natural looking flow of hair after just one procedure. Although desirable in principle, not all patients are suitable candidates nor is it possible to achieve in certain patients (eg, coarse or curly hair). Patients who have sufficient donor availability, reasonably stable hair loss, and high hair-to-skin color ratios are the ideal candidates. The authors highlight their philosophies and strategies for dense packing. PMID:24017984

Farjo, Bessam; Farjo, Nilofer

2013-08-01

443

Finding bridges in packings of colloidal spheres  

NASA Astrophysics Data System (ADS)

We identify putative load-bearing structures (bridges) in experimental colloidal systems studied by confocal microscopy. Bridges are co-operative structures that have been used to explain stability and inhomogeneous force transmission in simulated granular packings with a range of densities. We show that bridges similar to those found in granular simulations are present in real experimental colloidal packings. We describe critically the bridge-finding procedure for real experimental data and propose a new criterion-Lowest Mean Squared Separation (LSQS)-for selecting optimum stabilisations.

Jenkins, Matthew C.; Haw, Mark D.; Barker, Gary C.; Poon, Wilson C. K.; Egelhaaf, Stefan U.

444

Confined packings of frictionless spheres and polyhedra  

NASA Astrophysics Data System (ADS)

By means of numerical simulations, we study the influence of confinement on three-dimensional random close packed (RCP) granular materials subject to gravity. The effects of grain shape (spherical or polyhedral) and polydispersity on this dependence are investigated. In agreement with a simple geometrical model, the solid fraction is found to decrease linearly for increasing confinement no matter the grain shape. This decrease remains valid for bidisperse sphere packings although the gradient seems to reduce significantly when the proportion of small particles reaches 40% by volume. The aforementioned model is extended to capture the effect of the confinement on the coordination number.

Camenen, Jean-François; Descantes, Yannick; Richard, Patrick

2013-06-01

445

Packings and assemblies of hard convex polyhedra  

NASA Astrophysics Data System (ADS)

Dense packings of hard polyhedra have been studied for centuries due to their mathematical aesthetic and more recently for their applications in fields such as granular matter, amorphous matter, and biology. The spontaneous organization of hard polyhedra under compression has only recently been addressed, demonstrating a plethora of assembled complex structures. The infinite pressure dense packings and the finite pressure, thermodynamically assembled structures for a given shape, however, are often different. In this talk we investigate connections between those two limits for convex polyhedra. We discuss the possibility of predicting one limit from the other, discuss some general rules, and link with previous works.

Klotsa, Daphne; Chen, Elizabeth; Damasceno, Pablo; Engel, Michael; Glotzer, Sharon

2013-03-01

446

Research on One Borehole Hydraulic Coal Mining System  

NASA Astrophysics Data System (ADS)

The Borehole Hydraulic Coal Mining System (BHCMS) causes fragmentation of coal seams and removes coal slump through a drilled hole using high-pressure water jet. Then the mixture of coal and water as slurry are driven out of the borehole by hydraulic or air-lifting method, and are separated at the surface. This paper presents a case study of hydraulic borehole coal mining. The three key techniques of the BHCMS, namely, hydraulic lift of jet pump, air lift, and water jet disintegration are discussed and analyzed in this paper based on theoretical analysis and field experiments. Some useful findings have been obtained: (1) The design of jet pump, air lift system, and water jet has to be integrated appropriately in order to improve mining efficiency and coal recovery rate, and to decrease energy consumption. The design of hydraulic lift jet pump must meet the requirement of the minimum floating speed of coal particles. The optimization of nondimensional parameters and prevention of cavitation have to be considered in the design; (2) With regard to selecting the nozzle types of jet pump, center nozzle or annular nozzle can be selected according to the size of the removed particles; (3) Through air-lift and back pressure, the water head can be decreased to improve the lift capacity of jet pump and decrease the power loss. The air lift has great limitation if it is used solely to extract coal, but if it is employed in conjunction with jet pump, the lift capacity of jet pump can be increased greatly; (4) With water jets, the air lift can improve the fragmentation radius and capacity. The main factors that affect the effect of water jet are the submergible status of jet, jet pressure, and flowrate. The ideal jet of the monitor in the borehole hydraulic coal-mining system is a nonsubmergible free jet. Through air lift, the nonsubmergible free jet can be set up in the mining hole.

XIA, Bairu; ZENG, Xiping; MAO, Zhixin

447

Thermal hydraulics of valves for nuclear applications  

SciTech Connect

Thermal-hydraulic aspects of valves used in nuclear power plants are discussed. Emphasis is given to a review of recent work on safety and pressure relief valves, including the presentation of some experimental results describing one- and two-phase flow through such valves. Measurements of internal flow fields are presented. Significant flow separation occurs in both the safety and the pressure relief valves. An experimental study using high-speed photography to determine vaporization sites in safety valves when the flowing medium is initially a compressed liquid is described. A new method of estimating the observed decrease in valve coefficient when choked vapor flow changes to liquid flow is developed. This method also permits the prediction of the observed dependence of the valve coefficient on the receiver pressure in the choked and unchoked flow regimes. The fluid dynamic phenomena that lead to valve disk vibrations are discussed.

Sallet, D.W.

1984-11-01

448

Performance characteristics of hydraulic turbines and pumps. Proceedings of the Winter annual meeting, Boston, MA, November 13-18, 1983  

Microsoft Academic Search

Various topics are addressed under the headings: four quadrant and two-phase performance of turbines and pumps, cavitation in hydraulic turbines and pumps, pumps as power recovery turbines, and modeling and fluid dynamics in hydraulic turbines and pumps. Individual subjects considered include: representation of pump characteristics for transient analysis, prediction and measurement of the four-quadrant performance of an axial flow pump

G. Jr. Bennett; W. L. Swift

1983-01-01

449

Development of a lithium-ion battery pack system for EV  

Microsoft Academic Search

The lithium-ion battery has been commercialized in recent years mainly for use in small electric products. We have been researching energy sources for EV use that offer high levels of specific energy, specific power, cycle life and reliability. Among the many types of secondary batteries studied, a lithium-ion battery pack system with a cell control mechanism has been developed and

Hideaki Horie; Yuuji Tanjo; Takeshi Miyamoto; Yasunobu Koga

1997-01-01

450

25 kWe solar thermal stirling hydraulic engine system: Final conceptual design report  

SciTech Connect

This report documents the conceptual design and analysis of a solar thermal free-piston Stirling hydraulic engine system designed to deliver 25 kWe when coupled to the 11-meter Test Bed Concentrator at Sandia National Laboratories. A manufacturing cost assessment for 10,000 units per year was made by Pioneer Engineering and Manufacturing. The design meets all program objectives including a 60,000-hr design life, dynamic balancing, fully automated control, >33.3% overall system efficiency, properly conditioned power, maximum utilization of annualized insolation, and projected production costs of $300/kW. The system incorporates a simple, rugged, reliable pool boiler reflux heat pipe to transfer heat from the solar receiver to the Stirling engine. The free-piston engine produces high-pressure hydraulic flow which powers a commercial hydraulic motor that, in turn, drives a commercial rotary induction generator. The Stirling hydraulic engine uses hermetic bellows seals to separate helium working gas from hydraulic fluid which provides hydrodynamic lubrication to all moving parts. Maximum utilization of highly refined, field proven commercial components for electric power generation minimizes development cost and risk. The engine design is based on a highly refined Stirling hydraulic engine developed over 20 years as a fully implantable artificial heart power source. 4 refs., 19 figs., 3 tabs.

Not Available

1988-01-01

451

Sorption and desorption reactions of radionuclides with a crushed basalt-bentonite packing material  

SciTech Connect

Current design of waste packages for disposal of high-level radioactive wastes in underground basalt formations includes a layer of packing material that surrounds the waste container. One of the functions of this material is to limit the release of radionuclides from a breached container into groundwater by providing a low hydraulic conductivity zone and by sorbing dissolved radionuclides. The objective of this study was to assess the radionuclide sorption capability of a proposed packing material composed of 25% sodium bentonite and 75% crushed basalt (by weight). Sorption and desorption reactions of several important waste radioelements (neptunium, uranium, plutonium, technetium, selenium, and radium) were investigated in the absence of air at 90/sup 0/C. Uranium and neptunium were sorbed by slow reactions that follow first-order kinetics. The reaction rates are probably controlled by reduction of weakly sorbed uranium(VI) and neptunium(V) by ferrous iron in the crushed basalt component. Technetium(VII) was not reduced or sorbed under these conditions. Freundlich sorption and desorption isotherms for a given radionuclide were non-singular and show a strong tendency for sorption hysteresis. Applying the isotherm data to a one-dimensional transport model indicated that hysteretic sorption on the packing material provides an important safety factor in controlling releases of some radionuclides.

Barney, G.S.; Lane, D.L.; Allen, C.C.; Jones, T.E.

1985-04-01

452

Hydraulic fracturing with a refractory proppant for sand control  

SciTech Connect

A sand control and heat transfer method is described for use in a borehole having an unconsolidated or loosely consolidated oil or gas reservoir which is otherwise likely to introduce substantial amounts of sand into the borehole, comprising: (a) providing a borehole casing through the reservoir; (b) perforating the casing at preselected intervals therealong to form at least one of longitudinal, in-line perforations; (c) hydraulically fracturing the reservoir by injecting a fracturing fluid containing a fine grain fused refractory material which comprises substantially silicon carbide or silicon nitride, and a clay stabilizing agent; (d) injecting a proppant comprising a gravel packing fused refractory material comprised substantially of silicon carbide or silicon nitride into the fracture, whereby a first layer of fine grain fused refractory material is held in place along the entire face of the fracture by a second layer of gravel packing fused refractory material also extending along the entire length of the fracture thereby excluding fines; and (e) producing oil or gas from the reservoir through the fracture into the borehole casing via a thermal oil recovery method which proppant and layers provide for increased heat transfer into the formation.

Jennings, A.R. Jr.; Stowe, L.R.

1989-04-04

453

Isolation Enhancement Between Two Closely Packed Antennas  

Microsoft Academic Search

This paper introduces a coupling element to enhance the isolation between two closely packed antennas operating at the same frequency band. The proposed structure consists of two antenna elements and a coupling element which is located in between the two antenna elements. The idea is to use field cancellation to enhance isolation by putting a coupling element which artificially creates

Angus C. K. Mak; Corbett R. Rowell; Ross D. Murch

2008-01-01

454

Circle Packings and the Sacred Lotus  

Microsoft Academic Search

How must n non-overlapping equal circles be packed in a given circle so that the diameter of the circles will be as large as possible? This paper presents an account of this problem and its putative solutions and related configurations in lotus receptacles, classical Japanese mathematics (wasan) and traditional Japanese design. Particular emphasis is placed on the connection between the

Tibor Tarnai; Koji Miyazaki

2003-01-01

455

An adaptive packed-memory array  

Microsoft Academic Search

The packed-memory array (PMA) is a data structure that maintains a dynamic set of N elements in sorted order in a ?(N)-sized array. The idea is to intersperse ?(N) empty spaces or gaps among the elements so that only a small number of elements need to be shifted around on an insert or delete. Because the elements are stored physically

Michael A. Bender; Haodong Hu

2007-01-01

456

Parallel Approximation Algorithms for Bin Packing.  

National Technical Information Service (NTIS)

The authors study the parallel complexity of polynomial heuristics for the bin packing problem. They show that some well-known (and simple) methods like first-fit-decreasing are p-complete, and it is hence very unlikely that they can be efficiently parall...

R. J. Anderson E. W. Mayr M. K. Warmuth

1988-01-01

457

Simple Cloud Chambers Using Gel Ice Packs  

ERIC Educational Resources Information Center

|Although cloud chambers are highly regarded as teaching aids for radiation education, school teachers have difficulty in using cloud chambers because they have to prepare dry ice or liquid nitrogen before the experiment. We developed a very simple and inexpensive cloud chamber that uses the contents of gel ice packs which can substitute for dry…

Kamata, Masahiro; Kubota, Miki

2012-01-01

458

On the Online Bin Packing Problem  

Microsoft Academic Search

A new framework for analyzing online bin packing algorithms is presented. This framework presents a unified way of explaining the performance of algorithms based on the Harmonic approach [3, 5, 8, 10, 11, 12]. Within this framework, it is shown that a new algorithm, Harmonic++, has asymptotic performance ratio at most 1.58889. It is also shown that the analysis of

Steven S. Seiden

2001-01-01

459

Stuffed Derivatives of Close-Packed Structures  

ERIC Educational Resources Information Center

|Decades ago Buerger described and later Palmer reviewed stuffed silica crystal structures widely used by mineralogists. Many publications and books have discussed common crystal structures in terms of close-packing of one set of atoms or ions (P sites) with other atoms or ions in tetrahedral (T) or octahedral (O) sites. Douglas and Ho described…

Douglas, Bodie E.

2007-01-01

460

7 CFR 51.3152 - Standard pack.  

Code of Federal Regulations, 2013 CFR

...Nectarines packed in containers equipped with cell compartments, cardboard fillers or molded trays shall be of the proper size for the cells, fillers, or molds in which they are...measured at right angles to a line from stem to blossom end of the fruit....

2013-01-01

461

7 CFR 51.2338 - Standard pack.  

Code of Federal Regulations, 2013 CFR

... (1) Fruit packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size for the cells, fillers, or molds in which they are...measured at right angles to a line from stem to blossom end. (f) In order...

2013-01-01

462

7 CFR 51.630 - Standard Pack.  

Code of Federal Regulations, 2013 CFR

...AGRICULTURAL MARKETING ACT OF 1946 AND THE EGG PRODUCTS INSPECTION ACT FRESH...Fruits shall be fairly uniform in size, unless specified as uniform in size. When packed in approved containers... (b) âFairly uniform in sizeâ means that not more than...

2013-01-01

463

Hear Your Heart ClassPack  

NSDL National Science Digital Library

Using More Picture-Perfect Science Lessons: Using Children's Books to Guide Inquiry, K-4 in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatche

2010-04-22

464

Assessment of packing characteristics by computer simulation  

Microsoft Academic Search

Most relevant engineering mechanical properties of normal concretes such as compressive strength are to a large extent governed by the density and the uniformity of the aggregate packing as the load-bearing structure. Nevertheless, the integrity of this skeleton will gradually break down under increased loadings. In cementitious materials this is due to debonding of particle-matrix interfaces, which leads to crack

Piet Stroeven; Martijn Stroeven

1999-01-01

465

Chemical Change Caf� ClassPack  

NSDL National Science Digital Library

Using Picture-Perfect Science Lessons in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatched time-saver and a great deal. This Cla

2010-04-21

466

Oil well gravel packing method and apparatus  

Microsoft Academic Search

A method is given for transporting gravel to a production zone with a circulating well fluid to uniformly pack the gravel in the annular space in the wall between the perforated liner and the formation whereby the fluid enters the perforated liner after depositing gravel at the top of the annular column of gravel and flows through the liner inner

1976-01-01

467

Sheep in a Jeep ClassPack  

NSDL National Science Digital Library

Using Picture-Perfect Science Lessons in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatched time-saver and a great deal. This Cla

2010-04-21

468

Rice Is Life ClassPack  

NSDL National Science Digital Library

Using Picture-Perfect Science Lessons in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatched time-saver and a great deal. This Cla

2010-04-15

469

The Changing Moon ClassPack  

NSDL National Science Digital Library

Using Picture-Perfect Science Lessons in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatched time-saver and a great deal. This Cla

2010-04-21

470

How propping agents affect packed fractures  

Microsoft Academic Search

The final width of the packed fracture depends on its width at the end of the treatment and upon the amount of crushing and embedment caused by the applied load. The flow capacity of the fracture system is determined by this final fracture width and the effective permeability of the propping material. In this study, fracture permeability and widths are

Dunlap

1965-01-01

471

Day and Night ClassPack  

NSDL National Science Digital Library

Using Picture-Perfect Science Lessons in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatched time-saver and a great deal. This Cla

2010-04-21

472

Investigating the advantages and disadvantages of realistic approach and porous approach for closely packed pebbles in CFD simulation  

Microsoft Academic Search

A pebble bed geometry is usually adopted for high-temperature gas-cooled reactors (HTGRs), which exhibits inherently safe performance, high conversion efficiency, and low power density design. It is important to understand the thermal-hydraulic characteristics of HTGR core for optimum design and safe operation. Therefore, this study investigates the thermal-hydraulic behaviors in a segment of pebbles predicted by the Reynolds-averaged Navier–Stokes (RANS)

C. Y. Wu; Y. M. Ferng; C. C. Chieng; C. C. Liu

2010-01-01

473

Investigation of hydraulic transmission noise sources  

NASA Astrophysics Data System (ADS)

Advanced hydrostatic transmissions and hydraulic hybrids show potential in new market segments such as commercial vehicles and passenger cars. Such new applications regard low noise generation as a high priority, thus, demanding new quiet hydrostatic transmission designs. In this thesis, the aim is to investigate noise sources of hydrostatic transmissions to discover strategies for designing compact and quiet solutions. A model has been developed to capture the interaction of a pump and motor working in a hydrostatic transmission and to predict overall noise sources. This model allows a designer to compare noise sources for various configurations and to design compact and inherently quiet solutions. The model describes dynamics of the system by coupling lumped parameter pump and motor models with a one-dimensional unsteady compressible transmission line model. The model has been verified with dynamic pressure measurements in the line over a wide operating range for several system structures. Simulation studies were performed illustrating sensitivities of several design variables and the potential of the model to design transmissions with minimal noise sources. A semi-anechoic chamber has been designed and constructed suitable for sound intensity measurements that can be used to derive sound power. Measurements proved the potential to reduce audible noise by predicting and reducing both noise sources. Sound power measurements were conducted on a series hybrid transmission test bench to validate the model and compare predicted noise sources with sound power.

Klop, Richard J.

474

Fluid Power Technician  

ERIC Educational Resources Information Center

|Fluid power technicians, sometimes called hydraulic and pneumatic technicians, work with equipment that utilizes the pressure of a liquid or gas in a closed container to transmit, multiply, or control power. Working under the supervision of an engineer or engineering staff, they assemble, install, maintain, and test fluid power equipment.…

Moore, Pam

2008-01-01

475

Challenges in coupled thermal–hydraulics and neutronics simulations for LWR safety analysis  

Microsoft Academic Search

The simulation of nuclear power plant accident conditions requires three-dimensional (3D) modeling of the reactor core to ensure a realistic description of physical phenomena. The operational flexibility of Light Water Reactor (LWR) plants can be improved by utilizing accurate 3D coupled neutronics\\/thermal–hydraulics calculations for safety margins evaluations. There are certain requirements to the coupling of thermal–hydraulic system codes and neutron-kinetics

Kostadin Ivanov; Maria Avramova

2007-01-01

476

Dynamic Design of Electro-hydraulic Control Valve Based on Physical Simulation Model  

Microsoft Academic Search

Whether an electro-hydraulic control valve for the mixed-gas pressure control in a combined cycle power plant (CCPP) of a steel mill meets the challenge of the gas turbine depends on its dynamic response. To obtain the dynamic characteristics of the electro-hydraulic control valve before it is manufactured, a dynamic design approach based on the physical simulation model is presented. The

Yudong Xie; Yanjun Liu; Yong Wang

2009-01-01

477

Advanced energy saving hydraulic elevator  

SciTech Connect

An hydraulic elevator is described comprising: a counterweighted elevator comprising a car, a counterweight, and a rope connecting the car and the counterweight; a ram having a first reaction surface for driving one of the car or the counterweight upwardly and a second reaction surface for driving one of the car or the counterweight downwardly; multiplier means for moving the car a distance greater than a stroke of the ram, the multiplier means connecting the ram to the counterweighted elevator, the multiplier means comprising: a first pulley; a second pulley; means for rigidly connecting the first and second pulley, the means having a length corresponding to a rise of the hydraulic elevator, the means attaching to the ram; and a pulley rope which: has a first end attaching to a first fixed point, extends about the first pulley, extends about the second pulley, and has a second end attaching to a second fixed point.

Garrido, A.; Sevilleja, J.; Servia, A.

1993-08-24

478

Support for transmission shaft and hydraulic servo drum  

SciTech Connect

In a support for use in an automatic transmission apparatus of the type having a transmission shaft for transmitting power, an annular hydraulic servo drum and a piston fitted in the hydraulic servo drum for engaging and disengaging a friction engaging means is described, wherein the support has an axially extending tubular supporting portion having an inner peripheral surface for supporting the transmission shaft, an outer peripheral surface for supporting an inner cylindrical portion of the hydraulic servo drum, and working oil passages formed and adapted for supplying and discharging a working oil to and from the hydraulic servo drum. The improvement consists of: a support body made of light material having a first radially extending oil passage leading from an oil pressure controller for supplying and discharging a working oil and communicating with the inner peripheral surface of the tubular supporting portion; an inner sleeve of a heavier material than the support body fitting on the inner peripheral surface of the tubular supporting portion to cover the inner axially extending oil groove thereby forming an oil passage for working oil; and an outer sleeve of a heavier material than the support body fitting on the outer peripheral surface of the tubular supporting portion.

Kobayashi, K.; Sumiya, K.; Taga, Y.; Watanabe, K.

1987-09-15

479

Hydraulic Architecture of Vascular Plants  

Microsoft Academic Search

\\u000a When vascular plants are subjected to drought and eventually desiccate, they use different mechanisms to protect against water\\u000a losses. Within the liquid phase, changes in hydraulics refer to part of these mechanisms of stress avoidance, which exclude\\u000a the major role of gas exchange. At the input side, the water uptake by plant roots is governed by the composite structure\\u000a of

Ernst Steudle

480

Hydraulic conductivity of rice roots.  

PubMed

A pressure chamber and a root pressure probe technique have been used to measure hydraulic conductivities of rice roots (root Lp(r) per m(2) of root surface area). Young plants of two rice (Oryza sativa L.) varieties (an upland variety, cv. Azucena and a lowland variety, cv. IR64) were grown for 31-40 d in 12 h days with 500 micromol m(-2) s(-1) PAR and day/night temperatures of 27 degrees C and 22 degrees C. Root Lp(r) was measured under conditions of steady-state and transient water flow. Different growth conditions (hydroponic and aeroponic culture) did not cause visible differences in root anatomy in either variety. Values of root Lp(r) obtained from hydraulic (hydrostatic) and osmotic water flow were of the order of 10(-8) m s(-1) MPa(-1) and were similar when using the different techniques. In comparison with other herbaceous species, rice roots tended to have a higher hydraulic resistance of the roots per unit root surface area. The data suggest that the low overall hydraulic conductivity of rice roots is caused by the existence of apoplastic barriers in the outer root parts (exodermis and sclerenchymatous (fibre) tissue) and by a strongly developed endodermis rather than by the existence of aerenchyma. According to the composite transport model of the root, the ability to adapt to higher transpirational demands from the shoot should be limited for rice because there were minimal changes in root Lp(r) depending on whether hydrostatic or osmotic forces were acting. It is concluded that this may be one of the reasons why rice suffers from water shortage in the shoot even in flooded fields. PMID:11520872

Miyamoto, N; Steudle, E; Hirasawa, T; Lafitte, R

2001-09-01

481

Hydraulic Fracturing of Jointed Formations  

Microsoft Academic Search

Measured by volume, North America's largest hydraulic fracturing operations have been conducted at Fenton Hill, New Mexico to create geothermal energy reservoirs. In the largest operation 21,000 m³ of water were injected into jointed granitic rock at a depth of 3.5 km. Microearthquakes induced by this injection were measured with geophones placed in five wells drilled into, or very close,

H. D. Murphy; M. C. Fehler

1986-01-01

482

Hysteresis phenomena in hydraulic measurement  

NASA Astrophysics Data System (ADS)

Hysteresis phenomena demonstrate the lag between the generation and the removal of some physical phenomena. This paper studies the hysteresis phenomena of the head-drop in a scaled model pump turbine using experiment test and CFD methods. These lag is induced by complicated flow patterns, which influenced the reliability of rotating machine. Keeping the same measurement procedure is concluded for the hydraulic machine measurement.

Ran, H. J.; Luo, X. W.; Chen, Y. L.; Xu, H. Y.; Farhat, M.

2012-11-01

483

Optimal design of hydraulic support  

Microsoft Academic Search

.   This paper describes a procedure for optimal determination of two groups of parameters of a hydraulic support employed in\\u000a the mining industry. The procedure is based on mathematical programming methods. In the first step, the optimal values of\\u000a some parameters of the leading four-bar mechanism are found in order to ensure the desired motion of the support with minimal

M. Oblak; B. Harl; B. Butinar

2000-01-01

484

Thermal hydraulics development for CASL  

Microsoft Academic Search

This talk will describe the technical direction of the Thermal-Hydraulics (T-H) Project within the Consortium for Advanced Simulation of Light Water Reactors (CASL) Department of Energy Innovation Hub. CASL is focused on developing a 'virtual reactor', that will simulate the physical processes that occur within a light-water reactor. These simulations will address several challenge problems, defined by laboratory, university, and

Lowrie; Robert B

2010-01-01

485

Polycrystalline diamond compact bit hydraulics  

SciTech Connect

It is well understood and documented that bottomhole hydraulics plays an important role in conventional diamond bit performance. Recent industry experience has shown a similar importance with the new synthetic diamond compact bits. Certain types of polycrystalline diamond compact bits have cutters arranged in a reverse spiral mode. For optimum performance bit hydraulic design should be tailored to that reverse spiral mode. Theory reveals that a bit built with rectangular nozzles with a long axis in the tangential direction can give a fluid velocity envelope similar to the envelope of the reverse spiral. A rectangle can also reduce bit plugging by providing an increased perimeter in a non-concentric geometry. The introduction of rectangular nozzles into the bit renders the regular round nozzle pressure drop equation unsuitable for direct application. Extensive hydraulic tests were performed with different configurations of rectangular nozzles to establish more accurate pressure loss equations. The experiments included single nozzle studies and laboratory and field tests of bits. Field test results confirmed the reliability of the results obtained in the laboratory studies.

Knowlton, R.H.; Huang, H.; Iversen, B.

1982-09-01

486

Hydraulic erosion of cohesive riverbanks  

NASA Astrophysics Data System (ADS)

This study identifies and assesses the controls on hydraulic erosion of cohesive riverbanks on a 600-m reach of an urban ephemeral stream with active bank erosion. We examined hydraulic bank erosion by separating estimated bank shear stress into four properties: magnitude, duration, event peak, and variability. The values of these independent variables were used as a bank erosion context at three transects. Stepwise regression showed that the event peak (maximum peak) of excess shear stress best predicts cohesive bank erosion at the two transects with moderate critical shear stresses (1.93-4.08 N/m 2), while the variability (all peaks) of excess shear stress best predicts erosion at the transect with low critical shear stress (0.95 N/m 2). These results suggest that the amount of hydraulic erosion of cohesive riverbanks is dictated by flow peak intensities. Finally, the results of this study were combined with results from previous bank erosion studies to produce a conceptual model for estimating bank erosion rates based on their silt-clay content.

Julian, Jason P.; Torres, Raymond

2006-06-01

487

7 CFR 51.2840 - Export packing requirements.  

Code of Federal Regulations, 2013 CFR

...CERTIFICATION, AND STANDARDS) United States Standards for Grades of Onions (Other Than Bermuda-Granex-Grano and Creole Types) Export...Requirements § 51.2840 Export packing requirements. Onions specified as meeting Export Packing Requirements shall be...

2013-01-01

488

VIEW NORTHEAST, WEST FRONT OF PACKING SHED (BUILDING 20) AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW NORTHEAST, WEST FRONT OF PACKING SHED (BUILDING 20) AND BAMBOO STAND ALONG SOUTH FRONT - U.S. Plant Introduction Station, Packing Shed, 11601 Old Pond Road, Glenn Dale, Prince George's County, MD

489

Tray Pack Improved Durability Packaging Rough Handling Test Results.  

National Technical Information Service (NTIS)

The causes of damage to Tray Pack containers during rough handling were determined. Several concepts for increasing the stiffness of the Tray Pack container were developed. Prototypes were fabricated and tested. Shipping containers were tested for their a...

R. D. Cummings

1985-01-01

490

High temperature solar gas heating comparison between packed and fluidized bed receivers. I  

NASA Astrophysics Data System (ADS)

Experimental results are analyzed for packed and fluidized beds used as absorbers for solar thermal energy in conjunction with a heat engine. The packed bed was composed of porous material in the form of equally sized spheres, and a Runge-Kutta condition was used to solve a system of five first order differential equations and obtain the flux and temperature profiles. The solar receiver was configured as a spherical concentrator achieving magnification of up to 2000. The packed and fluidized beds were contained within quartz tubes. The thermal transport fluid was a gas, and ZrO2 and SiC were employed as the fluidized and packed materials. Attention was given to the mean penetration of solar radiation, the gas temperature level, and the system thermal efficiency. Temperatures of the beds ranged from 700-1500 K, with thermal efficiencies of 30-70 percent. Cavity receivers were found to yield the best efficiencies, and the packed bed receiver was considered to be a candidate for dispersed solar power systems equipped with Stirling engines.

Flamant, G.; Olalde, G.

491

Micro-hydroelectric power plant  

Microsoft Academic Search

A hydroelectric power plant is described comprising a penstock located in a stream diverting water therethrough from an intake basin located at a predetermined height above an outlet basin, a hydro turbine incorporated in a lower portion of the penstock having a rotor driven by the flow of water through the penstock, and a closed hydraulic system through which hydraulic

A. Jr. Rojo; J. Leiseca

1986-01-01

492

Wave-operated power plant  

Microsoft Academic Search

This wave-operated power plant comprises a perforated caisson breakwater in which propellers, or turbines, are mounted in the perforations or openings and drives hydraulic pumps connected thereto, which in turn drives a hydraulic motor coupled to an electric generator. One-way flap valves are mounted in the openings. Some of said flap valves allow the rushing waves to enter the caisson,

Ghesquiere

1980-01-01

493

Commercialization Effort for 1W Consumer Electronics Power Pack  

SciTech Connect

A commercial ready fuel cell charger has been further developed, demonstrated, and field tested during the three phases of this project. The work performed and demonstrated has shown the commercialization readiness of this future product and underlying technology. The tasks in phase 1 of the project focused on component cost reduction, redesign for manufacturability, performance & reliability testing, and system integration. The end of phase 1 was completed on time and was signified by passing the Go/No-Go checkpoint. As shown in the report all technical metrics have been met or exceeded and the Go/No-Go checkpoint was passed in November of 2009. The tasks in phase 2 focused on tool fabrication and tooled component prove-out in working systems. The end of Phase 2 was the accomplishment of building working systems made almost completely of tooled components. The tasks in phase 3 of the project were preparing for and executing a 75 unit field test of the DMFC charger product developed in Phase 1 and phase 2. This field test demonstrated the functionality of the DMFC in the hands of real users while also providing feedback for potential design improvements. This was the first time a significant number of MTI units were put into the field to test usability and functionality. Feedback from the field test was positive and the units functioned well in the field.

Carlstrom, Charles, M.

2011-06-29

494

Segregation and convection rolls in two-dimensional packings  

NASA Astrophysics Data System (ADS)

Self-organized pattern formation in two-dimensional packings is reported. Continuous rotation of a densely packed monolayer leads to two possible states: either the packing segregates without any recognizable collective particle motion, or the packing stays mixed and the particles move in regular convection rolls. The reason for the different observations is so far not known. Irrespective of the simplicity of the experiment, the driving mechanism must be completely different from other pattern forming systems in granular media.

Rietz, Frank

2013-06-01

495

Thermal-Hydraulic Analysis of Main-Steam-Line-Break Accidents as Potential Initiators for Reactor Vessel.  

National Technical Information Service (NTIS)

Results are presented from two thermal-hydraulic analyses of postulated main-steam-line breaks for the OCONEE nuclear power plant. One calculation assumes runaway feedwater supply, whereas normal feedwater management is used in the other. The analyses wer...

D. E. Lamkin

1983-01-01

496

Testing The Hybrid Hydraulic Drive Aircraft Tractor Via LXI Bus Technique  

Microsoft Academic Search

Based on the analysis of the structure and the power transmission system of aircraft towing tractor, a new project applying hydraulic drive hybrid power is put forward considering the requirements of towing aircraft and working process without towbar. As the testing and controlling signals of the system are multi channel and distributed, the testing program is designed via LXI bus.

Zhao Lijun; Yang Junguo; Jiang Jihai

497

Research on the Capacity of Hydraulic Pile Driving under Adding Force  

Microsoft Academic Search

High power using ratio in the process of pile driving of hydraulic static pile divers with quasi-constant-power is acquired. For being convenient for improving on the machine and quickening the course of pile driving , studying on the impact of the piston diameter of pile driving cylinder, the initial displacement of piston and the piston diameter of lift cylinder on

Xu Zhou; Qinghua He; Jianxin Zhu; Xiangyu He

2007-01-01

498

Repetitive control of an electro-hydraulic engine valve actuation system  

Microsoft Academic Search

Fully flexible engine valve systems serve as powerful rapid prototyping tools in research laboratories. With the ability to quickly design innovative valve strategies, researchers can explore the possibilities of improving fuel efficiency, power output and emissions through appropriately varying the valve lift, phasing and timing. One means of achieving variable valve motion is through an electro-hydraulic valve system (EHVS). However,

Hsien-Hsin Liao; Matthew J. Roelle; J. Christian Gerdes

2008-01-01

499

48 CFR 552.211-87 - Export packing.  

Code of Federal Regulations, 2012 CFR

...furnished with commercial or military export packing. Military export packing, if offered, shall be in accordance with Mil-Std-2073-1 Level A or B as specified. If commercial export packing is offered, the offer or pricelist shall include...

2012-10-01

500

48 CFR 552.211-87 - Export packing.  

Code of Federal Regulations, 2011 CFR

...furnished with commercial or military export packing. Military export packing, if offered, shall be in accordance with Mil-Std-2073-1 Level A or B as specified. If commercial export packing is offered, the offer or pricelist shall include...

2011-10-01