WorldWideScience

Sample records for hydraulic pump means

  1. Thermally Actuated Hydraulic Pumps

    Science.gov (United States)

    Jones, Jack; Ross, Ronald; Chao, Yi

    2008-01-01

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

  2. Remotely Adjustable Hydraulic Pump

    Science.gov (United States)

    Kouns, H. H.; Gardner, L. D.

    1987-01-01

    Outlet pressure adjusted to match varying loads. Electrohydraulic servo has positioned sleeve in leftmost position, adjusting outlet pressure to maximum value. Sleeve in equilibrium position, with control land covering control port. For lowest pressure setting, sleeve shifted toward right by increased pressure on sleeve shoulder from servovalve. Pump used in aircraft and robots, where hydraulic actuators repeatedly turned on and off, changing pump load frequently and over wide range.

  3. Constant-Pressure Hydraulic Pump

    Science.gov (United States)

    Galloway, C. W.

    1982-01-01

    Constant output pressure in gas-driven hydraulic pump would be assured in new design for gas-to-hydraulic power converter. With a force-multiplying ring attached to gas piston, expanding gas would apply constant force on hydraulic piston even though gas pressure drops. As a result, pressure of hydraulic fluid remains steady, and power output of the pump does not vary.

  4. Hydraulic development of high specific-speed pump-turbines by means of an inverse design method, numerical flow-simulation (CFD) and model testing

    Science.gov (United States)

    Kerschberger, P.; Gehrer, A.

    2010-08-01

    In recent years an increased interest in pump-turbines has been recognized in the market. The rapid availability of pumped storage schemes and the benefits to the power system by peak lopping, providing reserve and rapid response for frequency control are becoming of growing advantage. In that context it is requested to develop pump-turbines that reliably stand dynamic operation modes, fast changes of the discharge rate by adjusting the variable diffuser vanes as well as fast changes from pump to turbine operation. Within the present study various flow patterns linked to the operation of a pump-turbine system are discussed. In that context pump and turbine mode are presented separately and different load cases at both operation modes are shown. In order to achieve modern, competitive pump-turbine designs it is further explained which design challenges should be considered during the geometry definition of a pump-turbine impeller. Within the present study a runner-blade profile for a low head pump-turbine has been developed. For the initial hydraulic runner-blade design, an inverse design method has been applied. Within this design procedure, a first blade geometry is generated by imposing the pressure loading-distribution and by means of an inverse 3D potential-flow-solution. The hydraulic behavior of both, pump-mode and turbine-mode is then evaluated by solving the full 3D Navier-Stokes equations in combination with a robust turbulence model. Based on this initial design the blade profile has been further optimized and redesigned considering various hydraulic pump-turbine requirements. Finally, the progress in hydraulic design is demonstrated by model test results which show a significant improvement in hydraulic performance compared to an existing reference design.

  5. Hydraulic development of high specific-speed pump-turbines by means of an inverse design method, numerical flow-simulation (CFD) and model testing

    Energy Technology Data Exchange (ETDEWEB)

    Kerschberger, P; Gehrer, A, E-mail: peter.kerschberger@andritz.co [Andritz Hydro Graz A-8045 Graz, Reichsstrasse 68B (Austria)

    2010-08-15

    In recent years an increased interest in pump-turbines has been recognized in the market. The rapid availability of pumped storage schemes and the benefits to the power system by peak lopping, providing reserve and rapid response for frequency control are becoming of growing advantage. In that context it is requested to develop pump-turbines that reliably stand dynamic operation modes, fast changes of the discharge rate by adjusting the variable diffuser vanes as well as fast changes from pump to turbine operation. Within the present study various flow patterns linked to the operation of a pump-turbine system are discussed. In that context pump and turbine mode are presented separately and different load cases at both operation modes are shown. In order to achieve modern, competitive pump-turbine designs it is further explained which design challenges should be considered during the geometry definition of a pump-turbine impeller. Within the present study a runner-blade profile for a low head pump-turbine has been developed. For the initial hydraulic runner-blade design, an inverse design method has been applied. Within this design procedure, a first blade geometry is generated by imposing the pressure loading-distribution and by means of an inverse 3D potential-flow-solution. The hydraulic behavior of both, pump-mode and turbine-mode is then evaluated by solving the full 3D Navier-Stokes equations in combination with a robust turbulence model. Based on this initial design the blade profile has been further optimized and redesigned considering various hydraulic pump-turbine requirements. Finally, the progress in hydraulic design is demonstrated by model test results which show a significant improvement in hydraulic performance compared to an existing reference design.

  6. Design of Pumps for Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Klit, Peder; Olsen, Stefan; Bech, Thomas Nørgaard

    1999-01-01

    This paper considers the development of two pumps for water hydraulic applications. The pumps are based on two different working principles: The Vane-type pump and the Gear-type pump. Emphasis is put on the considerations that should be made to account for water as the hydraulic fluid.......KEYWORDS: water, pump, design, vane, gear....

  7. Technologies and Innovations for Hydraulic Pumps

    OpenAIRE

    Ivantysynova, Monika

    2016-01-01

    Positive displacement machines working as hydraulic pumps or hydraulic motors have always been, are and will be an essential part of any hydraulic system. Current trends and future demands on energy efficient systems will not only drastically increase the number of positive displacement machines needed for modern efficient hydraulic circuits but will significantly change the performance requirements of pumps and motors. Throttleless system configurations will change the landscape of hydraulic...

  8. Vibrations of hydraulic pump and their solution

    OpenAIRE

    Dobšáková Lenka; Nováková Naděžda; Habán Vladimír; Hudec Martin; Jandourek Pavel

    2017-01-01

    The vibrations of hydraulic pump and connected pipeline system are very problematic and often hardly soluble. The high pressure pulsations of hydraulic pump with the double suction inlet are investigated. For that reason the static pressure and accelerations are measured. The numerical simulations are carried out in order to correlate computed data with experimental ones and assess the main source of vibrations. Consequently the design optimization of the inner hydraulic part of pump is done ...

  9. Hydraulic refinement of an intraarterial microaxial blood pump.

    Science.gov (United States)

    Siess, T; Reul, H; Rau, G

    1995-05-01

    Intravascularly operating microaxial pumps have been introduced clinically proving to be useful tools for cardiac assist. However, a number of complications have been reported in literature associated with the extra-corporeal motor and the flexible drive shaft cable. In this paper, a new pump concept is presented which has been mechanically and hydraulically refined during the developing process. The drive shaft cable has been replaced by a proximally integrated micro electric motor and an extra-corporeal power supply. The conduit between pump and power supply consists of only an electrical power cable within the catheter resulting in a device which is indifferent to kinking and small curvature radii. Anticipated insertion difficulties, as a result of a large outer pump diameter, led to a two-step approach with an initial 6,4mm pump version and a secondary 5,4mm version. Both pumps meet the hydraulic requirement of at least 2.5l/min at a differential pressure of 80-100 mmHg. The hydraulic refinements necessary to achieve the anticipated goal are based on ongoing hydrodynamic studies of the flow inside the pumps. Flow visualization on a 10:1 scale model as well as on 1:1 scale pumps have yielded significant improvements in the overall hydraulic performance of the pumps. One example of this iterative developing process by means of geometrical changes on the basis of flow visualization is illustrated for the 6.4mm pump.

  10. The Hydraulic Ram (Or Impulse) Pump

    Science.gov (United States)

    Mills, Allan

    2014-01-01

    The hydraulic impulse pump utilizes a fraction of the momentum of a flowing stream to lift a small portion of that water to a higher level. There it may be accumulated in an elevated cistern to provide sufficient water for several families, for the pump works 24 h a day with no additional source of energy. The operation of the pump is described,…

  11. Prediction of potential failures in hydraulic gear pumps

    OpenAIRE

    E. Lisowski(Cracow Tech. U); J. Fabiś

    2010-01-01

    Hydraulic gear pumps are used in many machines and devices. In hydraulic systems of machines gear pumps are main component ofsupply unit or perform auxiliary function. Gear pumps opposite to vane pumps are less complicated. They consists of such components as:housing, gear wheels, bearings, shaft, seal for rotation motion which are not very sensitive for damage and that is why they are using veryoften. However, gear pumps are break down from time to time. Usually damage of pump cause shutting...

  12. Simulation of a Hydraulic Pump Control Valve

    Science.gov (United States)

    Molen, G. Vander; Akers, A.

    1987-01-01

    This paper describes the mode of operation of a control valve assembly that is used with a hydraulic pump. The operating system of the valve is modelled in a simplified form, and an analogy for hydraulic resonance of the pressure sensing system is presented. For the control valve investigated, air entrainment, length and diameter of the resonator neck, and valve mass produced the greatest shift in resonant frequency. Experimental work was conducted on the hydraulic system so that the resonance levels and frequencies could be measured and the accuracy of the theory verified. The results obtained make it possible to evaluate what changes to any of the variables considered would be most effective in driving the second harmonic frequency above the operating range.

  13. South Davis Sewer District Pump Station Hydraulic Capacity Evaluation

    OpenAIRE

    Dixon, James W

    2011-01-01

    In 2010, South Davis Sewer District (SDSD) determined that possible hydraulic problems existed in their various pump stations operating within their treatment plants. A hydraulic analysis was conducted for the pump stations to diagnose the problems and provide possible alternative solutions. This analysis was conducted by using hydraulic minor loss equations to determine the amount of flow that the pumps were capable of producing and then comparing those results to the required demands in the...

  14. Pump Application as Hydraulic Turbine – Pump as Turbine (PaT)

    OpenAIRE

    Rusovs, D

    2009-01-01

    The paper considers pump operation as hydraulic turbine with purpose to produce mechanical power from liquid flow. The Francis hydraulic turbine was selected for comparison with centrifugal pump in reverse operation. Turbine and centrifugal pump velocity triangles were considered with purpose to evaluate PaT efficiency. Shape of impeller blades for turbine and pumps was analysed. Specific speed calculation is carried out with purpose to obtain similarity in pump and turbine description. For ...

  15. Lubrication and tribology in seawater hydraulic piston pump

    Institute of Scientific and Technical Information of China (English)

    WANG Dong; LI Zhuang-yun; ZHU Yu-quan

    2003-01-01

    Water hydraulic systems have provoked major interest because of the human friendly and environmental safety aspects. Piston pump is one of the most frequently used hydraulic units in recent engineering technique. In water hydraulic piston pump, poor lubrication is more likely to happen than in oil hydraulic one because of difference in properties between water and oil. So there are some key problems such as corrosive wear and erosion, which are investigated briefly. Many new materials have been developed, which give longer life expectancies with water without corrosion and erosion. A new type of seawater hydraulic piston pumps with better suction characteristics had been developed at HUST. Much of this research has concentrated on new materials, structure and experiments, which are also specially introduced.

  16. WATER ENERGY IN HYDROAMELIORATIVE SYSTEMS USING THE HYDRAULIC TRANSFORMER TYPE A. BARGLAZAN AND THE HYDRAULIC HAMMER (HYDRAULIC PUMP

    Directory of Open Access Journals (Sweden)

    Teodor Eugen Man

    2010-01-01

    Full Text Available This paper presents two examples of exploitation of water energy that can be used in the irrigation field. First of theseexamples is the hydraulic transformer type A. Barglazan used for irrigation, pumped water is taken directly from theriver’s well, using a hydraulic pump which simultaneously carried out a double transformation in this way: hydraulicenergy into mechanic energy and mechanical energy into hydraulic energy. Technology preparation and devices designwas done in record time, seeing that this constructive solution is more robust, reliable and with improved energyperformance versus the laboratory prototype. The experimental research which was made at 1:1 scale proved theirgood function over time. Another example is the hydraulic hammer (hydraulic pump that uses low-head energy topump water, with a global efficiency of about 10 - 50%. Currently, the new situation of private ownership of landprovides conditions for new pumping microstations to be made where irrigation is necessary and optimal hydrauliclocations exist.

  17. Prediction of potential failures in hydraulic gear pumps

    Directory of Open Access Journals (Sweden)

    E. Lisowski

    2010-07-01

    Full Text Available Hydraulic gear pumps are used in many machines and devices. In hydraulic systems of machines gear pumps are main component ofsupply unit or perform auxiliary function. Gear pumps opposite to vane pumps are less complicated. They consists of such components as:housing, gear wheels, bearings, shaft, seal for rotation motion which are not very sensitive for damage and that is why they are using veryoften. However, gear pumps are break down from time to time. Usually damage of pump cause shutting down of machines and devices.One of the way for identifying potential failures and foreseeing their effects is a quality method. On the basis of these methods apreventing action might be undertaken before failure appear. In this paper potential failures and damages of a gear pump were presented bythe usage of matrix FMEA analysis.

  18. The numerical simulation based on CFD of hydraulic turbine pump

    Science.gov (United States)

    Duan, X. H.; Kong, F. Y.; Liu, Y. Y.; Zhao, R. J.; Hu, Q. L.

    2016-05-01

    As the functions of hydraulic turbine pump including self-adjusting and compensation with each other, it is far-reaching to analyze its internal flow by the numerical simulation based on CFD, mainly including the pressure field and the velocity field in hydraulic turbine and pump.The three-dimensional models of hydraulic turbine pump are made by Pro/Engineer software;the internal flow fields in hydraulic turbine and pump are simulated numerically by CFX ANSYS software. According to the results of the numerical simulation in design condition, the pressure field and the velocity field in hydraulic turbine and pump are analyzed respectively .The findings show that the static pressure decreases systematically and the pressure gradient is obvious in flow area of hydraulic turbine; the static pressure increases gradually in pump. The flow trace is regular in suction chamber and flume without spiral trace. However, there are irregular traces in the turbine runner channels which contrary to that in flow area of impeller. Most of traces in the flow area of draft tube are spiral.

  19. Design of a laboratory hydraulic device for testing of hydraulic pumps

    Directory of Open Access Journals (Sweden)

    Pavel Máchal

    2013-01-01

    Full Text Available The present contribution deals with solves problem of research of testing device to monitor of hydrostatic pumps durability about dynamic loading under laboratory conditions. When carrying out the design of testing device are based on load characteristics of tractor hydraulic circuit, the individual characteristics of hydraulic components and performed calculations. Load characteristics on the tractors CASE IH Magnum 310, JOHN DEERE 8100, ZETOR FORTERRA 114 41 and Fendt 926 Vario were measured. Design of a hydraulic laboratory device is based on the need for testing new types of hydraulic pumps or various types of hydraulic fluids. When creating of hydraulic device we focused on testing hydraulic pumps used in agricultural and forestry tractors. Proportional pressure control valve is an active member of the hydraulic device, which provides change of a continuous control signal into relative pressure of operating fluid. The advantage of a designed hydraulic system is possibility of simulation of dynamic operating loading, which is obtained by measurement under real conditions, and thereby creates laboratory conditions as close to real conditions as possible. The laboratory device is constructed at the Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra.

  20. Stability of Hydraulic Systems with Focus on Cavitating Pumps

    OpenAIRE

    Brennen, C. E.; Braisted, D. M.

    1980-01-01

    Increasing use is being made of transmission matrices to characterize unsteady flows in hydraulic system components and to analyze the stability of such systems. This paper presents some general characteristics which should be examined in any experimentally measured transmission matrices and a methodology for the analysis of the stability of transmission matrices in hydraulic systems of order 2. These characteristics are then examined for cavitating pumps and the predicted instabilities (kn...

  1. Servo Controlled Variable Pressure Modification to Space Shuttle Hydraulic Pump

    Science.gov (United States)

    Kouns, H. H.

    1983-01-01

    Engineering drawings show modifications made to the constant pressure control of the model AP27V-7 hydraulic pump to an electrically controlled variable pressure setting compensator. A hanger position indicator was included for continuously monitoring hanger angle. A simplex servo driver was furnished for controlling the pressure setting servovalve. Calibration of the rotary variable displacement transducer is described as well as pump performance and response characteristics.

  2. Simulation of three-demensional unsteady flow in hydraulic pumps

    NARCIS (Netherlands)

    Esch, van Bartholomeus Petrus Maria

    1997-01-01

    In this thesis it is shown that the flow in hydraulic pumps of the radial and mixedflow type, operating at conditions not too far from design point, can be considered as an incompressible potential flow, where the influence of viscosity is restricted to thin boundary layers, wakes and mixing areas.

  3. Design and Construction of a Hydraulic Ram Pump

    Directory of Open Access Journals (Sweden)

    Shuaibu Ndache MOHAMMED

    2007-09-01

    Full Text Available The Design and Fabrication of a Hydraulic Ram Pump (Hydram is undertaken. It is meant to lift water from a depth of 2m below the surface with no other external energy source required. Based on the design the volume flow rate in the derived pipe was 4.5238 × 10-5 m3/s (2.7 l/min, Power was 1.273 kW which results in an efficiency of 57.3%. The overall cost of fabrication of this hydram shows that the pump is relatively cheaper than the existing pumps.

  4. Little pump that could : hydraulic submersible pump tackles low pressure, low fluid volume gas wells

    Energy Technology Data Exchange (ETDEWEB)

    Ross, E.

    2008-03-15

    A new pump designed by Global Energy Services was described. The pump was designed to address problems associated with downhole pumps in coalbed methane (CBM) wells. The hydraulic submersible pump (HSP) was designed to address issues related to artificial lift gas lock and solids. The pump has been installed at 35 CBM wells in western Canada as well as at natural gas wells with low pressures and low rates of water. The HSP technology was designed for use with wells between 0.01 cubic metres and 24 cubic metres per day of water. A single joystick in the surface unit is used to determine the amount of hydraulic oil delivered to the bottomhole pump when then determines the amounts of fluid produced. A 10-slot self-flushing sand screen is used to filter out particles of sand, coal, and cement. The pump also includes a hydraulic flow control valve to control water volumes. The HSP's positive displacement design makes it suitable for use in horizontal and deviated wells. The pump technology is currently being re-designed to handle larger volumes at deeper depths. 2 figs.

  5. Position Sensorless Drive o SRM Mounted on Hydraulic Pump Unit

    Science.gov (United States)

    Kosaka, Takashi; Nabeya, Yoshinari; Ohyama, Kazunobu; Matsui, Nobuyuki

    Recently, Switched Reluctance Motors (SRM)have been applied to several industrial products such as fans, blowers, pumps and so forth because of their simple construction and relatively high e ciency.As one of the examples, Daikin Industries Ltd.has been successful in manufacturing hydraulic pump unit using 2.2kW three-phase SRM with shaft mounted position sensor for its control. This paper presents the position sensorless drive o the SRM for the purposes of reducing cost and down sizing of the hydraulic pump unit system.The controller, intentionally designed for this special application, realizes the following characteristics;the maximum and minimum speeds are 5000 and 300rpm, the speed response between the maximum and minimum speeds is within 100msec and the starting torque is less than 20% of the rated torque.The experimental studies using the hydraulic pump unit show that the proposed sensorless control scheme satis es the requirements for this application.

  6. Layered clustering multi-fault diagnosis for hydraulic piston pump

    Science.gov (United States)

    Du, Jun; Wang, Shaoping; Zhang, Haiyan

    2013-04-01

    Efficient diagnosis is very important for improving reliability and performance of aircraft hydraulic piston pump, and it is one of the key technologies in prognostic and health management system. In practice, due to harsh working environment and heavy working loads, multiple faults of an aircraft hydraulic pump may occur simultaneously after long time operations. However, most existing diagnosis methods can only distinguish pump faults that occur individually. Therefore, new method needs to be developed to realize effective diagnosis of simultaneous multiple faults on aircraft hydraulic pump. In this paper, a new method based on the layered clustering algorithm is proposed to diagnose multiple faults of an aircraft hydraulic pump that occur simultaneously. The intensive failure mechanism analyses of the five main types of faults are carried out, and based on these analyses the optimal combination and layout of diagnostic sensors is attained. The three layered diagnosis reasoning engine is designed according to the faults' risk priority number and the characteristics of different fault feature extraction methods. The most serious failures are first distinguished with the individual signal processing. To the desultory faults, i.e., swash plate eccentricity and incremental clearance increases between piston and slipper, the clustering diagnosis algorithm based on the statistical average relative power difference (ARPD) is proposed. By effectively enhancing the fault features of these two faults, the ARPDs calculated from vibration signals are employed to complete the hypothesis testing. The ARPDs of the different faults follow different probability distributions. Compared with the classical fast Fourier transform-based spectrum diagnosis method, the experimental results demonstrate that the proposed algorithm can diagnose the multiple faults, which occur synchronously, with higher precision and reliability.

  7. A teaspoon pump for pumping blood with high hydraulic efficiency and low hemolysis potential.

    Science.gov (United States)

    Dame, D

    1996-06-01

    Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.

  8. Low-power microfluidic electro-hydraulic pump (EHP).

    Science.gov (United States)

    Lui, Clarissa; Stelick, Scott; Cady, Nathaniel; Batt, Carl

    2010-01-07

    Low-power electrolysis-based microfluidic pumps utilizing the principle of hydraulics, integrated with microfluidic channels in polydimethylsiloxane (PDMS) substrates, are presented. The electro-hydraulic pumps (EHPs), consisting of electrolytic, hydraulic and fluidic chambers, were investigated using two types of electrodes: stainless steel for larger volumes and annealed gold electrodes for smaller-scale devices. Using a hydraulic fluid chamber and a thin flexible PDMS membrane, this novel prototype successfully separates the reagent fluid from the electrolytic fluid, which is particularly important for biological and chemical applications. The hydraulic advantage of the EHP device arises from the precise control of flow rate by changing the electrolytic pressure generated, independent of the volume of the reagent chamber, mimicking the function of a hydraulic press. Since the reservoirs are pre-filled with reagents and sealed prior to testing, external fluid coupling is minimized. The stainless steel electrode EHPs were manufactured with varying chamber volume ratios (1 : 1 to 1 : 3) as a proof-of-concept, and exhibited flow rates of 1.25 to 30 microl/min with electrolysis-based actuation at 2.5 to 10 V(DC). The miniaturized gold electrode EHPs were manufactured with 3 mm diameters and 1 : 1 chamber volume ratios, and produced flow rates of 1.24 to 7.00 microl/min at 2.5 to 10 V(AC), with a higher maximum sustained pressure of 343 KPa, suggesting greater device robustness using methods compatible with microfabrication. The proposed technology is low-cost, low-power and disposable, with a high level of reproducibility, allowing for ease of fabrication and integration into existing microfluidic lab-on-a-chip and analysis systems.

  9. Vibration Modes and the Dynamic Behaviour of a Hydraulic Plunger Pump

    Directory of Open Access Journals (Sweden)

    Tianxiao Zhang

    2016-01-01

    Full Text Available Mechanical vibrations and flow fluctuation give rise to complex interactive vibration mechanisms in hydraulic pumps. The working conditions for a hydraulic pump are therefore required to be improved in the design stage or as early as possible. Considering the structural features, parameters, and operating environment of a hydraulic plunger pump, the vibration modes for two-degree-of-freedom system were established by using vibration theory and hydraulic technology. Afterwards, the analytical form of the natural frequency and the numerical solution of the steady-state response were deduced for a hydraulic plunger pump. Then, a method for the vibration analysis of a hydraulic pump was proposed. Finally, the dynamic responses of a hydraulic plunger pump are obtained through numerical simulation.

  10. Solid Rocket Booster Hydraulic Pump Port Cap Joint Load Testing

    Science.gov (United States)

    Gamwell, W. R.; Murphy, N. C.

    2004-01-01

    The solid rocket booster uses hydraulic pumps fabricated from cast C355 aluminum alloy, with 17-4 PH stainless steel pump port caps. Corrosion-resistant steel, MS51830 CA204L self-locking screw thread inserts are installed into C355 pump housings, with A286 stainless steel fasteners installed into the insert to secure the pump port cap to the housing. In the past, pump port cap fasteners were installed to a torque of 33 Nm (300 in-lb). However, the structural analyses used a significantly higher nut factor than indicated during tests conducted by Boeing Space Systems. When the torque values were reassessed using Boeing's nut factor, the fastener preload had a factor of safety of less than 1, with potential for overloading the joint. This paper describes how behavior was determined for a preloaded joint with a steel bolt threaded into steel inserts in aluminum parts. Finite element models were compared with test results. For all initial bolt preloads, bolt loads increased as external applied loads increased. For higher initial bolt preloads, less load was transferred into the bolt, due to external applied loading. Lower torque limits were established for pump port cap fasteners and additional limits were placed on insert axial deformation under operating conditions after seating the insert with an initial preload.

  11. Mobile hydraulic power supply. Liquid piston Stirling engine pump

    Energy Technology Data Exchange (ETDEWEB)

    Ven, James D. van de [100 Institute Road, Department of Mechanical Engineering, Worcester Polytechnic Institute, Worcester, MA 01609 (United States)

    2009-11-15

    Conventional mobile hydraulic power supplies involve numerous kinematic connections and are limited by the efficiency, noise, and emissions of internal combustion engines. The Stirling cycle possesses numerous benefits such as the ability to operate from any heat source, quiet operation, and high theoretical efficiency. The Stirling engine has seen limited success due to poor heat transfer in the working chambers, difficulty sealing low-molecular weight gases at high pressure, and non-ideal piston displacement profiles. As a solution to these limitations, a liquid piston Stirling engine pump is proposed. The liquid pistons conform to irregular volumes, allowing increased heat transfer through geometry features on the interior of the working chambers. Creating near-isothermal operation eliminates the costly external heat exchangers and increases the engine efficiency through decreasing the engine dead space. The liquid pistons provide a positive gas seal and thermal transport to the working chambers. Controlling the flow of the liquid pistons with valves enables matching the ideal Stirling cycle and creates a direct hydraulic power supply. Using liquid hydrogen as a fuel source allows cooling the compression side of the engine before expanded the fuel into a gas and combusting it to heat the expansion side of the engine. Cooling the compression side not only increases the engine power, but also significantly increases the potential thermal efficiency of the engine. A high efficiency Stirling engine makes energy regeneration through reversing the Stirling cycle practical. When used for regeneration, the captured energy can be stored in thermal batteries, such as a molten salt. The liquid piston Stirling engine pump requires further research in numerous areas such as understanding the behavior of the liquid pistons, modeling and optimization of a full engine pump, and careful selection of materials for the extreme operating temperatures. Addressing these obtainable

  12. An evaluation of a hubless inducer and a full flow hydraulic turbine driven inducer boost pump

    Science.gov (United States)

    Lindley, B. K.; Martinson, A. R.

    1971-01-01

    The purpose of the study was to compare the performance of several configurations of hubless inducers with a hydrodynamically similar conventional inducer and to demonstrate the performance of a full flow hydraulic turbine driven inducer boost pump using these inducers. A boost pump of this type consists of an inducer connected to a hydraulic turbine with a high speed rotor located in between. All the flow passes through the inducer, rotor, and hydraulic turbine, then into the main pump. The rotor, which is attached to the main pump shaft, provides the input power to drive the hydraulic turbine which, in turn, drives the inducer. The inducer, rotating at a lower speed, develops the necessary head to prevent rotor cavitation. The rotor speed is consistent with present main engine liquid hydrogen pump designs and the overall boost pump head rise is sufficient to provide adequate main pump suction head. This system would have the potential for operating at lower liquid hydrogen tank pressures.

  13. Joint Estimation of Hydraulic and Poroelastic Parameters from a Pumping Test.

    Science.gov (United States)

    Berg, Steven J; Illman, Walter A; Mok, Chin Man W

    2015-01-01

    The coupling of hydraulic and poroelastic processes is critical in predicting processes involving the deformation of the geologic medium in response to fluid extraction or injection. Numerical models that consider the coupling of hydraulic and poroelastic processes require the knowledge of relevant parameters for both aquifer and aquitard units. In this study, we jointly estimated hydraulic and poroelastic parameters from pumping test data exhibiting "reverse water level fluctuations," known as the Noordbergum effect, in aquitards adjacent to a pumped aquifer. The joint estimation was performed by coupling BIOT2, a finite element, two-dimensional, axisymmetric, groundwater model that considers poroelastic effects with the parameter estimation code PEST. We first tested our approach using a synthetic data set with known parameters. Results of the synthetic case showed that for a simple layered system, it was possible to reproduce accurately both the hydraulic and poroelastic properties for each layer. We next applied the approach to pumping test data collected at the North Campus Research Site (NCRS) on the University of Waterloo (UW) campus. Based on the detailed knowledge of stratigraphy, a five-layer system was modeled. Parameter estimation was performed by: (1) matching drawdown data individually from each observation port and (2) matching drawdown data from all ports at a single well simultaneously. The estimated hydraulic parameters were compared to those obtained by other means at the site yielding good agreement. However, the estimated shear modulus was higher than the static shear modulus, but was within the range of dynamic shear modulus reported in the literature, potentially suggesting a loading rate effect.

  14. Performance optimization of grooved slippers for aero hydraulic pumps

    Institute of Scientific and Technical Information of China (English)

    Chen Juan; Ma Jiming; Li Jia; Fu Yongling

    2016-01-01

    A computational fluid dynamics (CFD) simulation method based on 3-D Navier–Stokes equation and Arbitrary Lagrangian–Eulerian (ALE) method is presented to analyze the grooved slip-per performance of piston pump. The moving domain of grooved slipper is transformed into a fixed reference domain by the ALE method, which makes it convenient to take the effects of rotate speed, body force, temperature, and oil viscosity into account. A geometric model to express the complex structure, which covers the orifice of piston and slipper, vented groove and the oil film, is constructed. Corresponding to different oil film thicknesses calculated in light of hydrostatic equilibrium theory and boundary conditions, a set of simulations is conducted in COMSOL to analyze the pump characteristics and effects of geometry (groove width and radius, orifice size) on these characteristics. Furthermore, the mechanics and hydraulics analyses are employed to validate the CFD model, and there is an excellent agreement between simulation and analytical results. The simulation results show that the sealing land radius, orifice size and groove width all dramatically affect the slipper behavior, and an optimum tradeoff among these factors is conducive to optimizing the pump design.

  15. Performance optimization of grooved slippers for aero hydraulic pumps

    Directory of Open Access Journals (Sweden)

    Juan Chen

    2016-06-01

    Full Text Available A computational fluid dynamics (CFD simulation method based on 3-D Navier–Stokes equation and Arbitrary Lagrangian–Eulerian (ALE method is presented to analyze the grooved slipper performance of piston pump. The moving domain of grooved slipper is transformed into a fixed reference domain by the ALE method, which makes it convenient to take the effects of rotate speed, body force, temperature, and oil viscosity into account. A geometric model to express the complex structure, which covers the orifice of piston and slipper, vented groove and the oil film, is constructed. Corresponding to different oil film thicknesses calculated in light of hydrostatic equilibrium theory and boundary conditions, a set of simulations is conducted in COMSOL to analyze the pump characteristics and effects of geometry (groove width and radius, orifice size on these characteristics. Furthermore, the mechanics and hydraulics analyses are employed to validate the CFD model, and there is an excellent agreement between simulation and analytical results. The simulation results show that the sealing land radius, orifice size and groove width all dramatically affect the slipper behavior, and an optimum tradeoff among these factors is conducive to optimizing the pump design.

  16. Use a Log Splitter to Demonstrate Two-Stage Hydraulic Pump

    Science.gov (United States)

    Dell, Timothy W.

    2012-01-01

    The two-stage hydraulic pump is commonly used in many high school and college courses to demonstrate hydraulic systems. Unfortunately, many textbooks do not provide a good explanation of how the technology works. Another challenge that instructors run into with teaching hydraulic systems is the cost of procuring an expensive real-world machine…

  17. PRESSURE OSCILLATIONS IN TRANSIENT PROCESSES OF HYDRAULIC SYSTEMS WITH VARIABLE DISPLACEMENT PUMPS

    Directory of Open Access Journals (Sweden)

    Hennadii Zaionchkovskyi

    2015-12-01

    Full Text Available In aviation hydraulic drive of high power as a power supply the axial-piston variable displacement pumps became wide spreaded. The pump operational modes with air isolation and cavitation are accompanied by increased noise, delivery reduction and intensive pressure oscillations. The negative results of such phenomena are hydraulic elements erosion, pipeline fatigue failure, working fluid viscosity reduction and its contamination by wear products. The mechanism of cavitation rising in axial-piston pumps is considered, and factors which influence the cavitation rising and working fluid aeration are specified. The features of transient processes in aircraft hydraulic systems with variable displacement pumps are considered. It has been showed that as the pump delivery changes from its minimum to maximum great pressure oscillations in the aircraft pressure pipeline of the hydraulic system takes place, and have a negative influence on the pump service life. The recommendations concerning such pressure oscillation reduction are given.

  18. NOISE IDENTIFICATION FOR HYDRAULIC AXIAL PISTON PUMP BASED ON ARTIFICIAL NEURAL NETWORKS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The noise identification model of the neural networks is established for the 63SCY14-1B hydraulic axial piston pump. Taking four kinds of different port plates as instances, the noise identification is successfully carried out for hydraulic axial piston pump based on experiments with the MATLAB and the toolbox of neural networks. The operating pressure, the flow rate of hydraulic axial piston pump, the temperature of hydraulic oil, and bulk modulus of hydraulic oil are the main parameters having influences on the noise of hydraulic axial piston pump. These four parameters are used as inputs of neural networks, and experimental data of the noise are used as outputs of neural networks. Error of noise identification is less than 1% after the neural networks have been trained. The results show that the noise identification of hydraulic axial piston pump is feasible and reliable by using artificial neural networks. The method of noise identification with neural networks is also creative one of noise theoretical research for hydraulic axial piston pump.

  19. Intelligent Hydraulic Actuator and Exp-based Modelling of Losses in Pumps and .

    DEFF Research Database (Denmark)

    Zhang, Muzhi

    A intelligent fuzzy logic self-organising PD+I controller for a gearrotor hydraulic motor was developed and evaluated. Furthermore, a experimental-based modelling methods with a new software tool 'Dynamodata' for modelling of losses in hydraulic motors and pumps was developed.......A intelligent fuzzy logic self-organising PD+I controller for a gearrotor hydraulic motor was developed and evaluated. Furthermore, a experimental-based modelling methods with a new software tool 'Dynamodata' for modelling of losses in hydraulic motors and pumps was developed....

  20. Test investigation on hydraulic losses in the discharge passage of an axial-flow pump

    Institute of Scientific and Technical Information of China (English)

    QIU Baoyun; CAO Haihong; JIANG Wei; GAO Zhaohui; WANG Fei

    2007-01-01

    In a discharge passage with a guide blade dis- charge circulation and secondary flow because of bend pipe, the flow in a 1-channel discharge passage of an axial flow pump is a complicated spiral flow. For a 2-channel passage, the discharge in the left channel is bigger than that in the fight, and the passage hydraulic losses are abnormal. In this study, the section current energy of the passage is accurately mea- sured and determined with a 5-hole probe. The hydraulic loss characteristics are determined and analyzed. The methods deducing the hydraulic losses are investigated. The results indicate that the passage hydraulic losses are not proportional to the flow discharge. Compared with a circular pipe, the hydraulic losses of a divergent discharge passage are smaller and the pump assembly efficiency is 10%-30% higher. As for the 1-channel passage, the axial-flow pump outlet circulation is usually too big; the passage hydraulic losses are also big, but a small circulation can slightly reduce hydraulic losses. As for the 2-channel passage, discharges in the two channels are not equal and the hydraulic losses increase. The outlet guide blade with a small discharge circulation or without circulation could reduce discharge passage hydraulic losses and increase pump assembly efficiency by 6%-11%.

  1. Intelligent Hydraulic Actuator and Exp-based Modelling of Losses in Pumps and .

    DEFF Research Database (Denmark)

    Zhang, Muzhi

    A intelligent fuzzy logic self-organising PD+I controller for a gearrotor hydraulic motor was developed and evaluated. Furthermore, a experimental-based modelling methods with a new software tool 'Dynamodata' for modelling of losses in hydraulic motors and pumps was developed....

  2. Joint inversion of hydraulic head and self-potential data associated with harmonic pumping tests

    Science.gov (United States)

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

    2016-09-01

    Harmonic pumping tests consist in stimulating an aquifer by the means of hydraulic stimulations at some discrete frequencies. The inverse problem consisting in retrieving the hydraulic properties is inherently ill posed and is usually underdetermined when considering the number of well head data available in field conditions. To better constrain this inverse problem, we add self-potential data recorded at the ground surface to the head data. The self-potential method is a passive geophysical method. Its signals are generated by the groundwater flow through an electrokinetic coupling. We showed using a 3-D saturated unconfined synthetic aquifer that the self-potential method significantly improves the results of the harmonic hydraulic tomography. The hydroelectric forward problem is obtained by solving first the Richards equation, describing the groundwater flow, and then using the result in an electrical Poisson equation describing the self-potential problem. The joint inversion problem is solved using a reduction model based on the principal component geostatistical approach. In this method, the large prior covariance matrix is truncated and replaced by its low-rank approximation, allowing thus for notable computational time and storage savings. Three test cases are studied, to assess the validity of our approach. In the first test, we show that when the number of harmonic stimulations is low, combining the harmonic hydraulic and self-potential data does not improve the inversion results. In the second test where enough harmonic stimulations are performed, a significant improvement of the hydraulic parameters is observed. In the last synthetic test, we show that the electrical conductivity field required to invert the self-potential data can be determined with enough accuracy using an electrical resistivity tomography survey using the same electrodes configuration as used for the self-potential investigation.

  3. Optimum Design of a Moving Coil Actuator for Fast-Switching Valves in Digital Hydraulic Pumps and Motors

    DEFF Research Database (Denmark)

    Roemer, Daniel Beck; Bech, Michael Møller; Johansen, Per

    2015-01-01

    Fast-switching seat valves suitable for digital hydraulic pumps and motors utilize direct electromagnetic actuators, which must exhibit superior transient performance to allow efficient operation of the fluid power pump/motor. A moving coil actuator resulting in a minimum valve switching time.......5 bar at 600 L/min flow rate, enabling efficient operation of digital hydraulic pumps and motors....

  4. Evaluation of hydraulic radial forces on the impeller by the volute in a centrifugal rotary blood pump.

    Science.gov (United States)

    Boehning, Fiete; Timms, Daniel L; Amaral, Felipe; Oliveira, Leonardo; Graefe, Roland; Hsu, Po-Lin; Schmitz-Rode, Thomas; Steinseifer, Ulrich

    2011-08-01

    In many state-of-the-art rotary blood pumps for long-term ventricular assistance, the impeller is suspended within the casing by magnetic or hydrodynamic means. For the design of such suspension systems, profound knowledge of the acting forces on the impeller is crucial. Hydrodynamic bearings running at low clearance gaps can yield increased blood damage and magnetic bearings counteracting high forces consume excessive power. Most current rotary blood pump devices with contactless bearings are centrifugal pumps that incorporate a radial diffuser volute where hydraulic forces on the impeller develop. The yielding radial forces are highly dependent on impeller design, operating point and volute design. There are three basic types of volute design--singular, circular, and double volute. In this study, the hydraulic radial forces on the impeller created by the volute in an investigational centrifugal blood pump are evaluated and discussed with regard to the choice of contactless suspension systems. Each volute type was tested experimentally in a centrifugal pump test setup at various rotational speeds and flow rates. For the pump's design point at 5 L/min and 2500 rpm, the single volute had the lowest radial force (∼0 N), the circular volute yielded the highest force (∼2 N), and the double volute possessed a force of approx. 0.5 N. Results of radial force magnitude and direction were obtained and compared with a previously performed computational fluid dynamics (CFD) study.

  5. Maintaining Optimum Pump Performance with Specially- Formulated Hydraulic Fluids

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This paper describes a battery of tests, and related results, that were performed under normal and severe conditions designed to demonstrate that hydraulic fluids formulated with Lubrizol' s high quality anti - wear hydraulic fluid technology can stand up to today's increasing demands for longer life and provide excellent performance under higher operating temperatures and pressures.

  6. In vitro evaluation of hydraulic characteristics of prototype implantable intrathecal infusion pump.

    Science.gov (United States)

    Nam, Kyoung Won; Sung, Mun Hyun; Kim, Hyun Ho; Kim, Kwang Gi; Kim, Dae Hyun; Lee, Byeong Han; Jo, Yung Ho

    2010-12-01

    The use of the intrathecal infusion pump for therapeutic treatment and pain management is increasing. For example, one such application is the pain treatment of cancer patients suffering from severe chronic pain, where all other treatment methods have failed. This method is gaining popularity because of its high cure effect with low dosage. In this study, we developed a prototype implantable intrathecal infusion pump and evaluated its mechanical and hydraulic characteristics in vitro to determine how its performance varied under different environmental conditions. The data are reported as means (standard deviations). In the experiments, the prototype pump could control the micro-scale infusion amount, and its performance was affected by ambient temperature and pressure conditions. In a temperature change test, at a constant pressure of 1.0 atm, the minimal amounts of a bolus were 4.44 (1.07), 5.06 (1.17), and 5.54 (0.90) uL for the temperature of 27.5, 36.5, and 42°C, respectively. In a pressure change test, at a constant temperature of 36.5°C, the minimal amounts of a bolus were 5.06 (1.17), 5.94 (0.67), and 6.13 (0.39) uL for pressures of 1.0, 0.9 and 0.8 atm, respectively. These experimental results demonstrate the possibility of using the prototype pump as an implantable microvolumetric infusion device. However, this prototype pump will have to undergo further design enhancement before being clinically feasible for such an application.

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    Efforts to overcome the inherent loss of energy due to throttling in valve driven hydraulic systems are many, and various approaches have been proposed by research communities as well as the industry. Recently, a so-called speed-variable differential pump was proposed for direct drive of hydraulic...... differential cylinders. The main idea was here to utilize an electric rotary drive, with the shaft interconnected to two antiparallel fixed displacement gear pumps, to actuate a differential cylinder. With the design carried out such that the area ratio of the cylinder matches the displacement ratio of the two...... gear pumps, the throttling losses are confined to cross port leakage in the cylinder and leakage of the pumps. However, it turns out that the volumetric pump losses and the pressure dynamics of the cylinder and connecting pipes may cause pressure increase- or decrease in the cylinder chambers, which...

  8. Internal hydraulic loss in a seal-less centrifugal Gyro pump.

    Science.gov (United States)

    Makinouchi, K; Ohara, Y; Sakuma, I; Damm, G; Mizuguchi, K; Jikuya, T; Takatani, S; Noon, G P; Nosé, Y

    1994-01-01

    A new index "loss factor Z" defined by Eq. 1 was introduced as the absolute expression of the mock loop resistance for testing a nonpulsatile pump. [formula: see text] where gamma is specific gravity of the fluid, g is the acceleration of gravity, delta P is total pressure head, and Q is flow. Z is expected to be constant, regardless of the pumping parameters. Z values obtained in the same mock loop but with different rotary blood pumps were almost identical and were defined as Z0. New methods of analysis of the flow-restrictive conditions of various rotary blood pumps are proposed in this paper: namely, differential loss factor delta Z, and loss factor sensitivity delta Z/delta A. The proposed Z-Q curves demonstrated better performance mapping than the conventional delta P-Q curves. Delta Z is the difference between the Z-Q curves of two different pumps. A is a design parameter of the pump; therefore delta Z/delta A is a quantitative expression of the effect of the design change on the hydraulic performance. These various indices were used to analyze the internal hydraulic loss of a centrifugal pump (Gyro pump). The relationship between its gap size (rotor casing) and hydraulic performance was assessed quantitatively by these indices. In this paper, the derivation processes and above-mentioned indices are described.

  9. A two-stage procedure for determining unsaturated hydraulic characteristics using a syringe pump and outflow observations

    DEFF Research Database (Denmark)

    Wildenschild, Dorthe; Jensen, Karsten Høgh; Hollenbeck, Karl-Josef;

    1997-01-01

    A fast two-stage methodology for determining unsaturated flow characteristics is presented. The procedure builds on direct measurement of the retention characteristic using a syringe pump technique, combined with inverse estimation of the hydraulic conductivity characteristic based on one......-step outflow experiments. The direct measurements are obtained with a commercial syringe pump, which continuously withdraws fluid from a soil sample at a very low and accurate how rate, thus providing the water content in the soil sample. The retention curve is then established by simultaneously monitoring......-step outflow data and the independently measured retention data are included in the objective function of a traditional least-squares minimization routine, providing unique estimates of the unsaturated hydraulic characteristics by means of numerical inversion of Richards equation. As opposed to what is often...

  10. Numerical Flow Analysis of a Hydraulic Gear Pump

    Science.gov (United States)

    Panta, Yogendra M.; Kim, Hyun W.; Pierson, Hazel M.

    2007-11-01

    The pressure that exists at the outlet port of a gear pump is a result of system load that was created by a resistance to the fluid flow. However, the flow pattern created inside an external gear pump by the motion of two oppositely rotating gears is deceptively complex, despite the simple geometry of the gear pump. The flow cannot be analyzed, based on a steady-state assumption that is usually employed to analyze turbo-machinery although the flow is essentially steady. Only the time-dependent, transient analysis with moving dynamic meshing technique can predict the motion of the fluid flow against the very high adverse pressure distribution. Although the complexity of analysis is inherent in all positive displacement pumps, gear pumps pose an exceptional challenge in modeling due to the fact that there are two rotating components that are housed within a stationary casing and the gears must be in contact with each other all the time. Fluent, commercially available computational fluid dynamics (CFD) software was used to analyze the flow of the gear pump. The investigation done by CFD produced significant information on flow patterns, velocity and pressure fields, and flow rates.

  11. Computational fluid dynamics-based hydraulic and hemolytic analyses of a novel left ventricular assist blood pump.

    Science.gov (United States)

    Yang, Xiao-Chen; Zhang, Yan; Gui, Xing-Min; Hu, Sheng-Shou

    2011-10-01

    The advent of various technologies has allowed mechanical blood pumps to become more reliable and versatile in recent decades. In our study group, a novel structure of axial flow blood pump was developed for assisting the left ventricle. The design point of the left ventricular assist blood pump 25 (LAP-25) was chosen at 4 Lpm with 100 mm Hg according to our clinical practice. Computational fluid dynamics was used to design and analyze the performance of the LAP-25. In order to obtain a required hydraulic performance and a satisfactory hemolytic property in the LAP-25 of a smaller size, a novel structure was developed including an integrated shroud impeller, a streamlined impeller hub, and main impeller blades with splitter blades; furthermore, tandem cascades were introduced in designing the diffuser. The results of numerical simulation show the LAP-25 can generate flow rates of 3-5 Lpm at rotational speeds of 8500-10,500 rpm, producing pressure rises of 27.5-148.3 mm Hg with hydraulic efficiency points ranging from 13.4 to 27.5%. Moreover, the fluid field and the hemolytic property of the LAP-25 were estimated, and the mean hemolysis index of the pump was 0.0895% with Heuser's estimated model. In conclusion, the design of the LAP-25 shows an acceptable result.

  12. Hydraulic forces caused by annular pressure seals in centrifugal pumps

    Science.gov (United States)

    Iino, T.; Kaneko, H.

    1980-01-01

    The hydraulic forces caused by annular pressure seals were investigated. The measured inlet and exit loss coefficients of the flow through the seals were much smaller than the conventional values. The results indicate that the damping coefficient and the inertia coefficient of the fluid film in the seal are not affected much by the rotational speed or the eccentricity of the rotor, though the stiffness coefficient seemed to be influenced by the eccentricity.

  13. Profile constructing and elevation design of soil reclaimed by hydraulic dredge pump in mining areas

    Energy Technology Data Exchange (ETDEWEB)

    Longqian, C.; Aiqin, S.; Tianjian, Z. [China Univ. of Mining and Technology, Xuzhou, Jiangsu (China). School of Environmental Science and Spatial Informatics; Mei, L. [China Univ. of Mining and Technology, Xuzhou, Jiangsu (China)

    2007-07-01

    Underground coal mining is the main method of coal mining in China. The hydraulic dredge pump reclamation method is the basic method used for repairing hydraulic erosion. This paper reviewed land reclamation by hydraulic dredge pump in the Yi'an coal mine of Xuzhou mining area in the east of China, and analyzed the constructing theory of soil profiling. It examined factors such as the height of the ground-water table; the thickness of plough horizon; the length of crops root and the state of soil erosion; and the methods of profile construction and elevation design of soil reclaimed by hydraulic dredge pump. A relevant mathematical model was also developed. The paper discussed the general situation of the study site as well as the basic theory of profile constructing and the profile constructing method. The paper also discussed the elevation design of the reclaimed land. It was concluded that the practice has proved that the methods can make the reclaimed soil keep a similar characteristics to that of original cropped soil, and meet the requirements for elevation of reclaimed land. 8 refs., 1 tab., 2 figs.

  14. CENTRIFUGAL PUMP AND SHAFT SEALING MEANS

    Science.gov (United States)

    Rushing, F.C.

    1960-09-01

    A description is given of sealing means between a hollow rotatable shaft and a stationary member surrounding the shaft which defines therewith a sealing space of annular cross-section, comprising a plurality of axially spaced rings held against seats by ring springs which serve to subdivide the sealing space- into a plurality of zones. Process gas introduced into the hollow shaft through a port communicating with a centrally located zone which iu turn communicates with a bore in the sleeve, is removed from the shaft through a second port communicating with an adjacent central zone and discharged through a second bore. A sealant gas is supplied to an end zone under a pressure sufficient to cause it to flow axially into adjacent zones and then maintained at a lower pressure than either the sealant gas source or the process gas inlet zone, preventing the sealant gas from entering the shaft and allowing gases leaking into the sealant gas to be withdrawn and led to a separator.

  15. Induced hydraulic pumping via integrated submicrometer cylindrical glass capillaries.

    Science.gov (United States)

    Cao, Zhen; Yobas, Levent

    2014-08-01

    Here, we report on a micropump that generates hydraulic pressure owing to a mismatch in EOF rates of microchannels and submicrometer cylindrical glass capillaries integrated on silicon. The electrical conductance of such capillaries in the dilute limit departs from bulk linear behavior as well as from the surface-charge-governed saturation in nanoslits that is well described by the assumption of a constant surface charge density. The capillaries show rather a gradual decrease in conduction at low salt concentrations, which can be explained more aptly by a variable surface charge density that accounts for chemical equilibrium of the surface. The micropump uses a traditional cross-junction structure with ten identical capillaries integrated in parallel on a side arm and each with a 750 nm diameter and 3 mm length. For an applied voltage of 700 V, a hydraulic pressure up to 5 kPa is generated with a corresponding flow velocity nearly 3 mm/s in a straight field-free branch 20 μm wide, 10 μm deep, and 10 mm long. The micropump utility has been demonstrated in an open tubular LC of three fluorescently labeled amino acids in just less than 20 s with minimal plate height values between 3 and 7 μm. The submicrometer capillaries are self-enclosed and produced through a unique process that does not require high-resolution advanced lithography or wafer-bonding techniques to define their highly controlled precise structures. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Mathematical Model Defining Volumetric Losses of Hydraulic Oil Compression in a Variable Capacity Displacement Pump

    Directory of Open Access Journals (Sweden)

    Paszota Zygmunt

    2015-01-01

    Full Text Available The objective of the work is to develop the capability of evaluating the volumetric losses of hydraulic oil compression in the working chambers of high pressure variable capacity displacement pump. Volumetric losses of oil compression must be determined as functions of the same parameters, which the volumetric losses due to leakage, resulting from the quality of design solution of the pump, are evaluated as dependent on and also as function of the oil aeration coefficient Ɛ. A mathematical model has been developed describing the hydraulic oil compressibility coefficient klc|Δppi;Ɛ;v as a relation to the ratio ΔpPi/pn of indicated increase ΔpPi of pressure in the working chambers and the nominal pressure pn, to the pump capacity coefficient bP, to the oil aeration coefficient  and to the ratio v/vnof oil viscosity v and reference viscosity vn. A mathematical model is presented of volumetric losses qpvc|ΔpPi;bp;;vof hydraulic oil compression in the pump working chambers in the form allowing to use it in the model of power of losses and energy efficiency

  17. Model predictive control of servo motor driven constant pump hydraulic system in injection molding process based on neurodynamic optimization

    Institute of Scientific and Technical Information of China (English)

    Yong-gang PENG; Jun WANG; Wei WEI

    2014-01-01

    In view of the high energy consumption and low response speed of the traditional hydraulic system for an injection molding machine, a servo motor driven constant pump hydraulic system is designed for a precision injection molding process, which uses a servo motor, a constant pump, and a pressure sensor, instead of a common motor, a constant pump, a pressure pro-portion valve, and a flow proportion valve. A model predictive control strategy based on neurodynamic optimization is proposed to control this new hydraulic system in the injection molding process. Simulation results showed that this control method has good control precision and quick response.

  18. Comparison of hydraulic and hemolytic properties of different impeller designs of an implantable rotary blood pump by computational fluid dynamics.

    Science.gov (United States)

    Arvand, Arash; Hahn, Nicole; Hormes, Marcus; Akdis, Mustafa; Martin, Michael; Reul, Helmut

    2004-10-01

    A mixed-flow blood pump for long-term applications has been developed at the Helmholtz-Institute in Aachen, Germany. Central features of this implantable pump are a centrally integrated motor, a blood-immersed mechanical bearing, magnetic coupling of the impeller, and a shrouded impeller, which allows a relatively wide clearance. The aim of the study was a numerical analysis of hydraulic and hemolytic properties of different impeller design configurations. In vitro testing and numerical simulation techniques (computational fluid dynamics [CFD]) were applied to achieve a comprehensive overview. Pressure-flow charts were experimentally measured in a mock loop in order to validate the CFD data. In vitro hemolysis tests were performed at the main operating point of each impeller design. General flow patterns, pressure-flow charts, secondary flow rates, torque, and axial forces on the impeller were calculated by means of CFD. Furthermore, based on streak line techniques, shear stress (stress loading), exposure times, and volume percentage with critical stress loading have been determined. Comparison of CFD data with pressure head measurements showed excel-lent agreement. Also, impressive trend conformity was observed between in-vitro hemolysis results and numerical data. Comparison of design variations yielded clear trends and results. Design C revealed the best hydraulic and hemolytic properties and was chosen as the final design for the mixed-flow rotary blood pump.

  19. Effects of radial diffuser hydraulic design on a double-suction centrifugal pump

    Science.gov (United States)

    Hou, H. C.; Zhang, Y. X.; Xu, C.; Zhang, J. Y.; Li, Z. L.

    2016-05-01

    In order to study effects of radial diffuser on hydraulic performance of crude oil pump, the steady CFD numerical method is applied and one large double-suction oil pump running in long-distance pipeline is considered. The research focuses on analysing the influence of its diffuser vane profile on hydraulic performance of oil pump. The four different types of cylindrical vane have been designed by in-house codes mainly including double arcs (DA), triple arcs (TA), equiangular spiral line (ES) and linear variable angle spiral line (LVS). During design process diffuser vane angles at inlet and outlet are tentatively given within a certain range and then the wrapping angle of the four types of diffuser vanes can be calculated automatically. Under the given inlet and outlet angles, the linear variable angle spiral line profile has the biggest wrapping angle and profile length which is good to delay channel diffusion but bring more friction hydraulic loss. Finally the vane camber line is thickened at the certain uniform thickness distribution and the 3D diffuser models are generated. The whole flow passage of oil pump with different types of diffusers under various flow rate conditions are numerically simulated based on RNG k-ɛ turbulent model and SIMPLEC algorithm. The numerical results show that different types of diffusers can bring about great difference on the hydraulic performance of oil pump, of which the ES profile diffuser with its proper setting angle shows the best hydraulic performance and its inner flow field is improved obviously. Compared with the head data from model sample, all designed diffusers can make a certain improvement on head characteristic. At the large flow rate conditions the hydraulic efficiency increases obviously and the best efficiency point shift to the large flow rate range. The ES profile diffuser embodies the better advantages on pump performance which can be explained theoretically that the diffuser actually acts as a diffusion

  20. Effects of staggered blades on the hydraulic characteristics of a 1400-MW canned nuclear coolant pump

    Directory of Open Access Journals (Sweden)

    Fang-Ming Zhou

    2016-08-01

    Full Text Available A canned nuclear coolant pump is used in an advanced third-generation pressurized water reactor. Impeller is a key component of a canned nuclear coolant pump. Usually, the blade is installed between the hub and the shroud as an entire part. The blade is divided into two parts and is staggered in the circumferential direction is an approach of blade design. To understand the effects of staggered blades on a canned nuclear coolant pump, this article numerically investigated different types of staggering. The validity of the numerical simulation was confirmed by comparing the numerical and experimental results. The performance change of a canned nuclear coolant pump with staggered blades was acquired. Hydraulic performance curves, axial force curves, static pressure distributions at the impeller outlet, and static pressure pulsations were performed to investigate the performance changes caused by the staggered blades. The results show that the staggered blade has an important influence on the performance of canned nuclear coolant pumps. A staggered blade does not improve hydraulic performance but does improve the axial force and pressure pulsation. Specifically, the staggered blades can significantly reduce the pressure pulsation amplitude on the impeller pass frequency.

  1. Hydraulic losses in the spiral case of low specific speed pumps

    Directory of Open Access Journals (Sweden)

    Klas Roman

    2014-03-01

    Full Text Available This contribution is focused on analysis of pressure losses in spiral case of centrifugal pump with thick trailing edges and with recirculation channels. Recirculation channels have different geometrical configuration and influence the size of available specific energy as well as hydraulic efficiency. Subsequently, the contribution analyses the flow in spiral case itself with respect to its function and its filling with liquid. Studied phenomena affect the research of pumps with low specific speed, the stability of specific energy characteristic curves and also the configuration of recirculation channels.

  2. FOUR WHEELS DRIVEN INDEPENDENTLY BY ONE PUMP DRIVING FOUR HYDRAULIC MOTORS

    Institute of Scientific and Technical Information of China (English)

    Wu Baolin; Qiu Lihua; Wang Zhanlin

    2005-01-01

    An improved Narendra model reference adaptive control (MRAC) scheme is proposed to research one variable displacement pump driving four hydraulic variable displacement motors. This approach not only ensures the underdamped and unstable system be global uniform asymptotic stability, but also has good robustness in these aspects of modeling uncertainty, pressure fluctuation of constant pressure network, and disturbance from external load, which also upgrades the rapidity of system response so as to make controlled system with nicer dynamic quality. The scheme of one pump driving four motors can meet the demand on off-road mobility of engineering vehicles and armored cars. A proof of stability about improved Narendra MRAC scheme is also given.

  3. Use of an oil-hydraulic microinjection pump for subretinal infusions.

    Science.gov (United States)

    Weichel, Judith; Valtink, Monika; Engelmann, Katrin; Richard, Gisbert

    2002-01-01

    The injection of cell suspensions or drugs into the subretinal space is a new promising option of vitreoretinal surgery for the treatment of degenerative retinal disorders. We used a manual oil-hydraulic microinjection pump to subretinally inject suspensions of retinal pigment epithelial cells in Royal College of Surgeons rats and in patients suffering from age-related macular degeneration with geographic atrophy. The histological examination of the treated rat eyes showed that cell suspensions could be placed precisely in the subretinal space. Intra- and postoperative outcome of the patients in the clinical trial revealed no retinal complications during 6 months of follow up. We suggest the oil-hydraulic microinjection pump to be a valuable instrument for controlled and precisely dosed atraumatic infusion or aspiration of small volumes of cell suspensions, fluids or drugs in vitreoretinal surgery.

  4. Prognostic for hydraulic pump based upon DCT-composite spectrum and the modified echo state network.

    Science.gov (United States)

    Sun, Jian; Li, Hongru; Xu, Baohua

    2016-01-01

    Prognostic is a key step of the condition-based maintenance (CBM). In order to improve the predicting performance, a novel method for prognostic for the hydraulic pump is proposed in this paper. Based on the improvement of the traditional composite spectrum, the DCT-composite spectrum (DCS) fusion algorithm is initially presented to make fusion of multi-channel vibration signals. The DCS composite spectrum entropy is extracted as the feature. Furthermore, the modified echo state networks (ESN) model is established for prognostic using the extracted feature. The reservoir is updated and the elements of the neighboring matrix are redefined for improving predicting accuracy. Analysis of the application in the hydraulic pump degradation experiment demonstrates that the proposed algorithm is feasible and is meaningful for CBM.

  5. Simultaneous transient operation of a high head hydro power plant and a storage pumping station in the same hydraulic scheme

    Science.gov (United States)

    Bucur, D. M.; Dunca, G.; Cervantes, M. J.; Cǎlinoiu, C.; Isbǎşoiu, E. C.

    2014-03-01

    This paper presents an on-site experimental analysis of a high head hydro power plant and a storage pumping station, in an interconnected complex hydraulic scheme during simultaneous transient operation. The investigated hydropower site has a unique structure as the pumping station discharges the water into the hydropower plant penstock. The operation regimes were chosen for critical scenarios such as sudden load rejections of the turbines as well as start-ups and stops with different combinations of the hydraulic turbines and pumps operation. Several parameters were simultaneously measured such as the pumped water discharge, the pressure at the inlet pump section, at the outlet of the pumps and at the vane house of the hydraulic power plant surge tank. The results showed the dependence of the turbines and the pumps operation. Simultaneous operation of the turbines and the pumps is possible in safe conditions, without endangering the machines or the structures. Furthermore, simultaneous operation of the pumping station together with the hydropower plant increases the overall hydraulic efficiency of the site since shortening the discharge circuit of the pumps.

  6. Spring 1961 hydraulic head in the lower pumped zone of California's Central Valley (from Williamson and others, 1989)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset defines the spring 1961 hydraulic head in the lower pumped zone of California's Central Valley. It was used to initiate the water-level...

  7. Hydraulic design and pre-whirl regulation law of inlet guide vane for centrifugal pump

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new hydraulic design method of three-dimensional guide vane for centrifugal pump is proposed on the assumption that the fluid at the outlet of guide vane satisfies the uniform velocity moment condition.The geometry of blade is controlled by the distributed rule of blade angles along the meridional streamline which is described by a fourth-order polynomial.Experiment results demonstrate that the designed guide vane can overcome the drawback of two-dimensional guide vane,enlarge the high efficiency scope and improve the hydraulic performance of centrifugal pump on the off-design operation conditions.In comparison with the performance of the centrifugal pump without inlet guide vane,the peak value of efficiency can be enhanced by 2.13% after the three-dimensional guide vane was being installed.The three-dimensional entire flow field of the centrifugal pump with inlet guide vane is simulated,and the basic principle and mechanism of inlet guide vane pre-whirl regulation are analyzed.The validity of design method has been proved.

  8. Investigation and Parameter Optimization of a Hydraulic Ram Pump Using Taguchi Method

    Science.gov (United States)

    Sarma, Dhrupad; Das, Monotosh; Brahma, Bipul; Pandwar, Deepak; Rongphar, Sermirlong; Rahman, Mafidur

    2016-10-01

    The main objective of this research work is to investigate the effect of Waste Valve height and Pressure Chamber height on the output flow rate of a Hydraulic ram pump. Also the second objective of this work is to optimize them for a hydraulic ram pump delivering water up to a height of 3.81 m (12.5 feet ) from the ground with a drive head (inlet head) of 1.86 m (6.11 feet). Two one-factor-at-a-time experiments have been conducted to decide the levels of the selected input parameters. After deciding the input parameters, an experiment has been designed using Taguchi's L9 Orthogonal Array with three repetitions. Analysis of Variance (ANOVA) is carried out to verify the significance of effect of the factors on the output flow rate of the pump. Results show that the height of the Waste Valve and height of the Pressure Chamber have significant effect on the outlet flow of the pump. For a pump of drive pipe diameter (inlet pipe) 31.75 mm (1.25 in.) and delivery pipe diameter of 12.7 mm (0.5 in.) the optimum setting was found out to be at a height of 114.3 mm (4.5 in.) of the Waste Valve and 406.4 mm (16 in.) of the Pressure vessel providing a delivery flow rate of 93.14 l per hour. For the same pump estimated range of output flow rate is, 90.65-94.97 l/h.

  9. Investigation and Parameter Optimization of a Hydraulic Ram Pump Using Taguchi Method

    Science.gov (United States)

    Sarma, Dhrupad; Das, Monotosh; Brahma, Bipul; Pandwar, Deepak; Rongphar, Sermirlong; Rahman, Mafidur

    2016-06-01

    The main objective of this research work is to investigate the effect of Waste Valve height and Pressure Chamber height on the output flow rate of a Hydraulic ram pump. Also the second objective of this work is to optimize them for a hydraulic ram pump delivering water up to a height of 3.81 m (12.5 feet ) from the ground with a drive head (inlet head) of 1.86 m (6.11 feet). Two one-factor-at-a-time experiments have been conducted to decide the levels of the selected input parameters. After deciding the input parameters, an experiment has been designed using Taguchi's L9 Orthogonal Array with three repetitions. Analysis of Variance (ANOVA) is carried out to verify the significance of effect of the factors on the output flow rate of the pump. Results show that the height of the Waste Valve and height of the Pressure Chamber have significant effect on the outlet flow of the pump. For a pump of drive pipe diameter (inlet pipe) 31.75 mm (1.25 in.) and delivery pipe diameter of 12.7 mm (0.5 in.) the optimum setting was found out to be at a height of 114.3 mm (4.5 in.) of the Waste Valve and 406.4 mm (16 in.) of the Pressure vessel providing a delivery flow rate of 93.14 l per hour. For the same pump estimated range of output flow rate is, 90.65-94.97 l/h.

  10. Variables Form and Use of Hydraulic Pump%液压泵的变量形式及使用

    Institute of Scientific and Technical Information of China (English)

    马卫宏

    2013-01-01

    This paper introduces several common hydraulic variable displacement form of analysis of several variable displace-ment hydraulic pump to adapt their working conditions, elaborated variable displacement hydraulic pump selection and use should pay attention to the problems of actual use for different working conditions in the form of variable displacement hy-draulic pump used to provide a reference.%介绍液压泵的几种常用的变排量形式,分析了几种变排量液压泵各自适应的工况,阐述了选择及使用变排量液压泵应注意的问题,为实际使用中针对不同的工况而选用液压泵的变排量形式提供了参考。

  11. Hydraulics.

    Science.gov (United States)

    Decker, Robert L.; Kirby, Klane

    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)…

  12. Quasi-three dimensional hydraulic design and performance calculation of high specific speed mixed-flow pump

    Science.gov (United States)

    Su, M.; Zhang, Y. X.; Zhang, J. Y.; Hou, H. C.

    2016-05-01

    According to the basic parameters of 211-80 high specific speed mixed-flow pump, based on the quasi-three dimensional flow theory, the hydraulic design of impeller and its matching spaced guide vanes for high specific speed mixed flow pump was completed, in which the iterative calculation of S 1, S 2 stream surfaces was employed to obtain meridional flow fields and the point-by-point integration method was employed to draw blade camber lines. Blades are thickened as well as blade leading edges are smoothed in the conformal mapping surface. Subsequently the internal fields of the whole flow passage of the designed pump were simulated by using RANS equations with RNG k-ε two-equation turbulent model. The results show that, compared with the 211-80 model, the hydraulic efficiency of the designed pump at the optimal flow rate increases 9.1%. The hydraulic efficiency of designed pump in low flow rate condition (78% designed flow rate) increases 6.46%. The hydraulic efficiency in high flow rate areas increases obviously and there is no bad phenomenon of suddenly decrease of hydraulic efficiency in model pump. From the distributions of velocity and pressure fields, it can be seen that the flow in impeller is uniform and the increase of pressure is gentle. There are no obvious impact phenomenon on impeller inlet and obvious wake shedding vortex phenomenon from impeller outlet to guide vanes inlet.

  13. A novel high-temperature and high-pressure hydraulic pump based on mononeuron control

    Institute of Scientific and Technical Information of China (English)

    Linhui ZHAO; Xin FANG

    2009-01-01

    Based on structures and characteristics of traditional hydraulic pumps, this paper proposes a novel high-temperature and high-pressure hydraulic pump (HHHP) that can work under 150℃ and 28MPa to overcome problems of traditional high-temperature plun-ger pumps. The HHHP is designed with the structure of mechanical division and double cylinder parallel. The control signals of two cylinders are two separate triangle waveforms with 90℃ phase difference. Because the output waveforms of two cylinders have the same characteristics as the control signals, the HHHP can obtain a stable output after two separate waveforms are superposed. A mono-neuron self-adaptive PID control algorithm is also improved by modifying parameters K and η. Two improved controllers are used to control the two cylinders,respectively, making two displacements of plungers match each other. Therefore, reduced fluctuations and stable pressure output is obtained. Besides simulation, tests on the built prototype test system are carried out to verify the performance of HHHP. Results show that the improved control approach can limit fluctuations to a lower level and the HHHP system attains good outputs under different signal periods and different pressures.

  14. Variable stiffness actuator based on fluidic flexible matrix composites and piezoelectric-hydraulic pump

    Science.gov (United States)

    Kim, Gi-Woo; Li, Suyi; Wang, K. W.

    2010-04-01

    Recently, a new biological-inspired fluidic flexible matrix composite (in short, F2MC) concept has been developed for linear/torsional actuation and structural stiffness tailoring. Although the actuation and the variable stiffness features of the F2MC have been successfully demonstrated individually, their combined functions and full potentials were not yet manifested. In addition, the current hydraulic pressurization systems are bulky and heavy, limiting the potential of the F2MC actuator. To address these issues, we synthesize a new variable stiffness actuator concept that can provide both effective actuation and tunable stiffness (dual-mode), incorporating the F2MC with a compact piezoelectric-hydraulic pump (in short, PHP). This dual-mode mechanism will significantly enhance the potential of the F2MC adaptive structures.

  15. Design of Hydraulic Pump Detector Based on ARM%基于ARM的液压泵检测仪设计

    Institute of Scientific and Technical Information of China (English)

    高立龙; 王新晴; 蒋文峰; 张红涛

    2013-01-01

    Aim at the conditions that engineering machine has big fluidity, engineering machine hydraulic system is complex and hydraulic pump detection is difficult on the spot. This paper introduces a design of the portable hydraulic pump detector based on ARM embedded system. This detector has S3C6410A based on ARM11 as the core processor, designing signal regulate circuit, photoelectric isolating circuit and friendly data acquisition software, introducing the installation and test methods of hydraulic pump detection, realizing the collection of pump meters and the hydraulic pump performance test on the spot.%针对工程机械流动性大、液压系统复杂、液压泵现场检测困难等情况.该文设计了一种基于ARM嵌入式系统的便携式液压泵检测仪,该检测仪以ARM 11类型处理器S3C6410A为核心,设计了相应的信号整流电路、光电隔离电路和友好的数据采集软件,介绍了液压泵现场检测的安装和检测方法,实现了液压泵参数的现场快速采集和性能曲线的现场绘制.

  16. Estimation of changes in dynamic hydraulic force in a magnetically suspended centrifugal blood pump with transient computational fluid dynamics analysis.

    Science.gov (United States)

    Masuzawa, Toru; Ohta, Akiko; Tanaka, Nobuatu; Qian, Yi; Tsukiya, Tomonori

    2009-01-01

    The effect of the hydraulic force on magnetically levitated (maglev) pumps should be studied carefully to improve the suspension performance and the reliability of the pumps. A maglev centrifugal pump, developed at Ibaraki University, was modeled with 926 376 hexahedral elements for computational fluid dynamics (CFD) analyses. The pump has a fully open six-vane impeller with a diameter of 72.5 mm. A self-bearing motor suspends the impeller in the radial direction. The maximum pressure head and flow rate were 250 mmHg and 14 l/min, respectively. First, a steady-state analysis was performed using commercial code STAR-CD to confirm the model's suitability by comparing the results with the real pump performance. Second, transient analysis was performed to estimate the hydraulic force on the levitated impeller. The impeller was rotated in steps of 1 degrees using a sliding mesh. The force around the impeller was integrated at every step. The transient analysis revealed that the direction of the radial force changed dynamically as the vane's position changed relative to the outlet port during one circulation, and the magnitude of this force was about 1 N. The current maglev pump has sufficient performance to counteract this hydraulic force. Transient CFD analysis is not only useful for observing dynamic flow conditions in a centrifugal pump but is also effective for obtaining information about the levitation dynamics of a maglev pump.

  17. Numerical analysis on the cavitation and unsteady flow in a scroll hydraulic pump

    Science.gov (United States)

    Sun, S. H.; Guo, P. C.; Huang, Y.; Zuo, J. L.; Luo, X. Q.

    2016-05-01

    This paper presents numerical analysis of unsteady flow in a scroll hydraulic pump to discover its flow mechanism. The dynamic mesh model has to be used to simulate the flow field unsteadily. The unsteady flow patterns and pressure distributions in the suction, squeezing and discharge chamber are analysed. The suction process continues until the crank angle reaches the 320 degree. Then the pressure in the chamber rises instantaneously, and the fluid begins to flow out from the chamber. Because of the high pressure difference at the clearance, the jet flow and the vortex appear, and the large flow losses generates with them. In addition, the velocity and static pressure distribution in the two symmetry crescent suction chamber is different remarkably. One reason is that the location of suction port cannot be set symmetrically for the simplification of the pump structure. Another reason for that is the fluid is impelled by different part of the orbiting scroll. The asymmetric pressure distribution will result in the extra force on the scroll. The cavitation generates at the negative pressure region. Therefore, the unsteady simulation shows some important phenomena. The structure of the scroll pump need to be optimized to reduce the maximum pressure, weaken the jet flow, vortex and the uneven pressure distribution to ensure the pump working safely and efficiently.

  18. Optimization on the impeller of a low-specific-speed centrifugal pump for hydraulic performance improvement

    Science.gov (United States)

    Pei, Ji; Wang, Wenjie; Yuan, Shouqi; Zhang, Jinfeng

    2016-09-01

    In order to widen the high-efficiency operating range of a low-specific-speed centrifugal pump, an optimization process for considering efficiencies under 1.0 Q d and 1.4 Q d is proposed. Three parameters, namely, the blade outlet width b 2, blade outlet angle β 2, and blade wrap angle φ, are selected as design variables. Impellers are generated using the optimal Latin hypercube sampling method. The pump efficiencies are calculated using the software CFX 14.5 at two operating points selected as objectives. Surrogate models are also constructed to analyze the relationship between the objectives and the design variables. Finally, the particle swarm optimization algorithm is applied to calculate the surrogate model to determine the best combination of the impeller parameters. The results show that the performance curve predicted by numerical simulation has a good agreement with the experimental results. Compared with the efficiencies of the original impeller, the hydraulic efficiencies of the optimized impeller are increased by 4.18% and 0.62% under 1.0 Q d and 1.4Qd, respectively. The comparison of inner flow between the original pump and optimized one illustrates the improvement of performance. The optimization process can provide a useful reference on performance improvement of other pumps, even on reduction of pressure fluctuations.

  19. Feed-pump hydraulic performance and design improvement, Phase I: research program design. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Brown, W.H.; Gopalakrishnan, S.; Fehlau, R.; Thompson, W.E.; Wilson, D.G.

    1982-03-01

    As a result of prior EPRI-sponsored studies, it was concluded that a research program should be designed and implemented to provide an improved basis for the design, procurement, testing, and operation of large feed pumps with increased reliability and stability over the full range of operating conditions. This two-volume report contains a research plan which is based on a review of the present state of the art and which defines the necessary R and D program and estimates the benefits and costs of the program. The recommended research program consists of 30 interrelated tasks. It is designed to perform the needed research; to verify the results; to develop improved components; and to publish computer-aided design methods, pump specification guidelines, and a troubleshooting manual. Most of the technology proposed in the research plan is applicable to nuclear power plants as well as to fossil-fired plants. This volume contains appendixes on pump design, cavitation damage, performance testing, hydraulics, two-phase flow in pumps, flow stability, and rotor dynamics.

  20. By-pass Devices as Effective Means of Protection from the Hydraulic Hammer

    Directory of Open Access Journals (Sweden)

    Khalid S. Al-Rababa

    2005-01-01

    Full Text Available Switching-off the parallel working pump units causes sudden discharge changes in parallel pipe lines, as a result of that hydraulic shocks takes place. The damping of these shocks can be achieved by the installation of the by-pass devices between the parallel lines of the piping system. The analytical calculations demonstrate that the reduction in hydraulic shocks reaches 40% and considerable part of the electric power (from 5 up to 21% is economized by using the by-pass devices, the duration of pressure decline decreases by more than 1,5 times. Comparison of the calculations based on the developed algorithm with the results of practical studies at the pumping station (Syrdarya has shown good convergence of analytical and experimental outcomes.

  1. Comparisons of Hydraulic Performance in Permanent Maglev Pump for Water-Jet Propulsion

    Directory of Open Access Journals (Sweden)

    Puyu Cao

    2014-08-01

    Full Text Available The operation of water-jet propulsion can generate nonuniform inflow that may be detrimental to the performance of the water-jets. To reduce disadvantages of the nonuniform inflow, a rim-driven water-jet propulsion was designed depending on the technology of passive magnetic levitation. Insufficient understanding of large performance deviations between the normal water-jets (shaft and permanent maglev water-jets (shaftless is a major problem in this paper. CFD was directly adopted in the feasibility and superiority of permanent maglev water-jets. Comparison and discussion of the hydraulic performance were carried out. The shaftless duct firstly has a drop in hydraulic losses (K1, since it effectively avoids the formation and evolution of the instability secondary vortex by the normalized helicity analysis. Then, the shaftless intake duct improves the inflow field of the water-jet pump, with consequencing the drop in the backflow and blocking on the blade shroud. So that the shaftless water-jet pump delivers higher flow rate and head to the propulsion than the shaft. Eventually, not only can the shaftless model increase the thrust and efficiency, but it has the ability to extend the working range and broaden the high efficiency region as well.

  2. Optical fiber grating vibration sensor for vibration monitoring of hydraulic pump

    Science.gov (United States)

    Zhang, Zhengyi; Liu, Chuntong; Li, Hongcai; He, Zhenxin; Zhao, Xiaofeng

    2017-06-01

    In view of the existing electrical vibration monitoring traditional hydraulic pump vibration sensor, the high false alarm rate is susceptible to electromagnetic interference and is not easy to achieve long-term reliable monitoring, based on the design of a beam of the uniform strength structure of the fiber Bragg grating (FBG) vibration sensor. In this paper, based on the analysis of the vibration theory of the equal strength beam, the principle of FBG vibration tuning based on the equal intensity beam is derived. According to the practical application of the project, the structural dimensions of the equal strength beam are determined, and the optimization design of the vibrator is carried out. The finite element analysis of the sensor is carried out by ANSYS, and the first order resonant frequency is 94.739 Hz. The vibration test of the sensor is carried out by using the vibration frequency of 35 Hz and the vibration source of 50 Hz. The time domain and frequency domain analysis results of test data show that the sensor has good dynamic response characteristics, which can realize the accurate monitoring of the vibration frequency and meet the special requirements of vibration monitoring of hydraulic pump under specific environment.

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

    Directory of Open Access Journals (Sweden)

    A. F. Golovchuk

    2013-04-01

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

  4. The Development of Water Hydraulic Transmission and Water Hydraulic Axial Piston Pump (Motor)%水压传动及柱塞泵(马达)的现状和发展

    Institute of Scientific and Technical Information of China (English)

    聂松林; 张铁华; 李壮云

    2000-01-01

    介绍了国内外水压传动技术及其水压轴向柱塞泵(马达)的设计制造和发展。%Introduces the developments of Water Hydraulic transmission and Water Hydraulic Axial Piston Pump (Motor). The challenges for designing water hydraulic components and analyzed.

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    proportional valves, this design allows to control the lower chamber pressure levels, throttling excess compression flow to tank. The resulting design introduces additional losses due to throttling of excess compression flow, but also improves the dynamic properties of the system significantly. The proposed...... differential cylinders. The main idea was here to utilize an electric rotary drive, with the shaft interconnected to two antiparallel fixed displacement gear pumps, to actuate a differential cylinder. With the design carried out such that the area ratio of the cylinder matches the displacement ratio of the two...... may seriously influence the dynamics and hence the performance during operation. This paper presents an analysis of these properties, and a redesign of the hydraulic system concept is proposed. Here the area- and displacement ratios are deliberately mismatched, causing inherent pressure build...

  6. Effects of volute geometry and impeller orbit on the hydraulic performance of a centrifugal pump

    Science.gov (United States)

    Flack, R. D.; Lanes, R. F.

    1983-01-01

    Overall performance data was taken for a Plexiglas water pump with a logarithmic spiral volute and rectangular cross sectioned flow channels. Parametric studies were made in which the center of the impeller was offset from the design center of the volute. The rig was also designed such that the impeller was allowed to synchronously orbit by a fixed amount about any center. The studies indicate that decreasing the tongue clearance decreases the head at low flowrates and increases the head at high flowrates. Also, decreasing the volute area in the first half of the volute and holding the tongue clearance the same, resulted in a decreased head for low flowrates but performance at high flowrates was not affected. Finally, the overall hydraulic performance was not affected by the impeller orbitting about the volute center.

  7. 3D Blade Hydraulic Design Method of the Rotodynamic Multiphase Pump Impeller and Performance Research

    Directory of Open Access Journals (Sweden)

    Yongxue Zhang

    2014-02-01

    Full Text Available A hydraulic design method of three-dimensional blade was presented to design the blades of the rotodynamic multiphase pump. Numerical simulations and bench test were conducted to investigate the performance of the example impeller designed by the presented method. The results obtained from the bench test were in good agreement with the simulation results, which indicated the reasonability of the simulation. The distributions of pressure and gas volume fraction were analyzed and the results showed that the designed impeller was good for the transportation of mixture composed of gas and liquid. In addition, the advantage of the impeller designed by the presented method was suitable for using in large volume rate conditions, which were reflected by the comparison of the head performance between this three-dimensional design method and another one.

  8. Lead-free, bronze-based surface layers for wear resistance in axial piston hydraulic pumps

    Energy Technology Data Exchange (ETDEWEB)

    Vetterick, Gregory Alan [Iowa State Univ., Ames, IA (United States)

    2010-01-01

    Concerns regarding the safety of lead have provided sufficient motivation to develop substitute materials for the surface layer on a thrust bearing type component known as a valve plate in axial piston hydraulic pumps that consists of 10% tin, 10% lead, and remainder cooper (in wt. %). A recently developed replacement material, a Cu-10Sn-3Bi (wt.%) P/M bronze, was found to be unsuitable as valve plate surface layer, requiring the development of a new alloy. A comparison of the Cu-1-Sn-10Pb and Cu-10Sn-3Bi powder metal valve plates showed that the differences in wear behavior between the two alloys arose due to the soft phase bismuth in the alloy that is known to cause both solid and liquid metal embrittlement of copper alloys.

  9. Virtual Training System for Hydraulic Pump Cart Based on Virtual Reality

    Directory of Open Access Journals (Sweden)

    Wusha Huang

    2013-08-01

    Full Text Available This paper dissertates the application of Virtual Reality Technology in the training process. Virtual training system has more advantages than traditional training system. The design of virtual training system based on PTC DIVISION Mockup software, position tracker and 3-D mouse is proposed. The system is divided into two parts: directing part and operating part. Collision detection is discussed to improve the sense of reality in the virtual environment .This system is applied to the training process of hydraulic pump cart’s assembly and disassembly. More immersive training effect is obtained in this system. The goal of reducing training costs and improving the efficiency of training can be achieved in the virtual training system.  

  10. Hydraulic concentration of magnetic fields in the solar photosphere. I - Turbulent pumping

    Science.gov (United States)

    Parker, E. N.

    1974-01-01

    Observations suggest that most of the magnetic flux through the solar photosphere is concentrated in vertical filaments in the supergranule boundaries. Each filament appears to contain about 3 times 10 to the 18-th power maxwells, in the form of a field of 500 gauss or more, over a diameter of 700 km or less. The magnetic energy density in the filaments is 100 times the observed kinetic energy density of the observed supergranule motions, but comparable to the kinetic energy density of the granules. Force-free field configurations cannot duplicate the observational numbers, nor can such cooling effects as are believed responsible for the intense fields in sunspot umbrae. We point out a simple hydraulic mechanism (turbulent pumping) that appears to account for the observed concentration of fields.

  11. 液压泵试验台系统设计%Research of Test System of Hydraulic Pump

    Institute of Scientific and Technical Information of China (English)

    阳宝元; 黄志坚; 何曼

    2015-01-01

    One test system of hydraulic pump which includes hydraulic system, electronic control system and computer control system is de-signed, and some critical types of components are selected. The whole system is simple, practical which can reliably and quickly test perfor-mance parameters of hydraulic pump.%设计了一种液压泵试验台系统,包括液压系统、电控系统和计算机测控系统,对系统的相关元件进行了选型,整个系统简单实用,能可靠、快捷地对液压泵的性能参数进行测试。

  12. Centrifugal slurry pump wear and hydraulic studies. Quarterly technical progress report, January 1, 1987--March 31, 1987

    Energy Technology Data Exchange (ETDEWEB)

    Bonney, G.E. [Ingersoll-Rand Co., Phillipsburg, NJ (United States)

    1987-01-01

    The following report marks the third quarter of the third phase of the centrifugal slurry pump improvement program. The program was begun in 1982 for the purpose of improving the operating life of centrifugal slurry pumps for coal liquefaction service. This phase of work will verify the design of a pump at higher speed operation. Eventual scale-up of the prototype slurry pumps to full-scale synthetic fuel generation plants could require ten times the flow. The higher speed will allow pumps to be smaller with respectable efficiencies. Conversely, without increasing the specific speed of the pump design, the eventual size would be more than triple that of the prototype slurry pump. The prototype slurry pump during this phase of the program incorporated all the features proven in the earlier phases of the program. This new, higher specific speed pump will be tested for the ability of the hydraulic design to inhibit wear. It will be tested and compared to the previous optimum prototype slurry pump of this program.

  13. Stability analysis of the governor-turbine-hydraulic system of pumped storage plant during small load variation

    Science.gov (United States)

    Yu, X. D.; Zhang, J.; Chen, S.; Liu, J. C.

    2016-11-01

    Governor-turbine-hydraulic (GTH) system is complex because of strong couplings of hydraulic, mechanical and electrical system. This paper presents a convenient mathematical model of the GTH system of a pumped storage plant (PSP) during small load variation. By using state space method and eigenvalue method, the stability of the GTH system is analyzed and the stable regions of the system can be given as well, which would help to optimize system design or the turning of governors. The proposed method is used to analyze the stability of a practical pumped storage plant during small load variation, which is also simulated in time domain on the basis of characteristics method. The theoretical analysis is in good agreement with numerical simulations. Based on the proposed method, the effect of the system parameters and operating conditions on the stable regions is investigated. These results are useful for the design of the GTH system of pumped storage plants.

  14. Research Progress of Hydraulic Pumping Unit%液压抽油机的研究进展

    Institute of Scientific and Technical Information of China (English)

    梁宏宝; 王晓宇; 石镇铭; 刘旭

    2015-01-01

    Hydraulic pumping oil unit can take the maximize advantage of the productivity of oil wells in oil exploitation, full of energy conservation, and has been attached great importance to domestic and foreign oilfield engineering technical personnel. Along with the hydraulic technology improved, the hydraulic pumping unit was developed rapidly, and was applied in oilfield production with certain amount. The development of hydraulic pumping unit was studied systematically with comprehension in aspects of structure, con⁃trol and matched weight at home and abroad in recent 5 years. It is discussed of existing problems and the required direction of further study of the hydraulic pumping unit.%液压抽油机在石油开采中能最大限度地发挥油井产能,充分节约能源,得到了国内外油田工程技术人员的高度重视。随着液压技术的提高,使液压抽油机得到迅速地发展,并在油田生产中得到了一定的应用。针对近五年国内外液压抽油机的结构、控制、配重等方面系统综述了液压抽油机的研究进展,讨论了目前存在的问题和需要进一步研究的方向。

  15. Investigations of hydraulic operating conditions of air lift pump with three types of air-water mixers

    Directory of Open Access Journals (Sweden)

    Kalenik Marek

    2015-03-01

    Full Text Available Investigations of hydraulic operating conditions of air lift pump with three types of air-water mixers. The paper presents the analysis of results of the investigations concerning the influence of various constructive solutions of the air-water mixers on hydraulic operating conditions of the air lift pump. The scope of the investigations encompassed the determination of characteristics of delivery head and delivery rate for three types of air-water mixers applied in the constructed air lift pump. Using the obtained results, the efficiency of the three types of air-water mixers applied in this air lift pump was determined. The analysis was carried out and there was checked whether the improved analytical Stenning-Martin model can be used to design air lift pumps with the air-water mixers of these types. The highest capacity in the water transport was reached by the air lift pump with the 1st type air-water mixer, the lowest one – with the 3rd type air-water mixer. The water flow in the air lift pump increases along with the rise in the air flow. The lower are the hydraulic losses generated during flow of the air flux by the air-water mixer, the higher is the air lift pump capacity. Along with the rise in the water delivery head, the capacity of the air lift pump decreases. The highest efficiency is reached by the air lift pump with the 1st type air-water mixer, the lowest – with the 3st type air-water mixer. The efficiency of the air lift pump for the three investigated types of air-water mixers decreases along with the rise in air flow rate and water delivery head. The values of submergence ratio (h/L of the delivery pipe, calculated with the use of the improved analytical Stenning-Martin model, coincide quite well with the values of h/L determined from the measurements.

  16. 46 CFR 28.840 - Means for stopping pumps, ventilation, and machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Means for stopping pumps, ventilation, and machinery. 28.840 Section 28.840 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY UNINSPECTED VESSELS... pumps, ventilation, and machinery. All electrically driven fuel oil transfer pumps, fuel oil unit...

  17. DETERMINATION OF HYDRAULIC TURBINE EFFICIENCY BY MEANS OF THE CURRENT METER METHOD

    Directory of Open Access Journals (Sweden)

    PURECE C.

    2016-12-01

    Full Text Available The paper presents methodology used for determining the efficiency of a low head Kaplan hydraulic turbine with short converging intake. The measurement method used was the current meters method, the only measurement method recommended by the IEC 41standard for flow measurement in this case. The paper also presents the methodology used for measuring the flow by means of the current meters method and the various procedures for calculating the flow. In the last part the paper presents the flow measurements carried out on the Fughiu HPP hydraulic turbines for determining the actual operating efficiency.

  18. The design of hyperthermia hydraulic pump station%高温型液压泵站的设计

    Institute of Scientific and Technical Information of China (English)

    王华安; 武光玉

    2013-01-01

    the article refer to key point of design of hyperthermia hydraulic pump station.This kind of pump station can supply hydraulic oil whose pressure is up to 21 MPa 、quantity of flow is up to 30 L/min when its temperature is120℃ ,and it also can be used as a formal station.%本文介绍了高温型泵站的设计要点。该泵站能够提供温度至120℃、压力至21MPa、流量至30L/min的压力油,亦可作为常规泵站使用。

  19. Evaluation of advanced hydraulic turbomachinery for underground pumped hydroelectric storage. Part 1. Single-stage regulated pump turbines for operating heads of 500 to 1000 m

    Energy Technology Data Exchange (ETDEWEB)

    Frigo, A.A.; Blomquist, C.A.; Degnan, J.R.

    1979-10-01

    High-head, large-capacity turbomachinery is needed for the concept of underground pumped hydroelectric storage to be technically and economically attractive. Single-stage, reversible, Francis-type pump turbines with adjustable wicket gates appear to offer the most economically attractive option for heads between about 500 and 1000 m. The feasibility of developing these types of machines for capacities up to 500 MW and operating heads up to 1000 m has been evaluated. Preliminary designs have been generated for six single-stage pump turbines. The designs are for capacities of 350 and 500 MW and for operating heads of 500, 750, and 1000 m. The report contains drawings of the machines along with material specifications and hydraulic performance data. Mechanical, hydraulic, and economic analyses indicate that these machines will behave according to the criteria used to design them and that they can be built at a reasonable cost. The stress and deflection responses of the 500-MW, 100-m-head pump turbine, determined by detailed finite element analysis techniques, give solid evidence of the integrity of the conceptual designs of the six units and indicate no unsolvable problems. Results of a life expectancy analysis of the wicket gates indicate that a near infinite life can be expected for these components when they are subjected to normal design loads. Efficiencies of 90.7 and 91.4% in the generating and pumping modes, respectively, can be expected for the 500-MW, 1000-m-head unit. Performances of the other five machines are comparable. The specific costs of the pump turbines in mid-1978 US dollars per kW vary from 19.2 to 11.8 over a head range of from 500 to 1000 m for the 500-MW machines and from 20.0 to 12.3 for the 350-MW machines.

  20. Investigation on the influence of leakage clearance on the flow field and performance of scroll hydraulic pump

    Science.gov (United States)

    Sun, Shuaihui; Huang, Yi; Guo, Pengcheng; Zuo, Juanli; Luo, Xingqi

    2016-11-01

    In the present paper, the computer fluid dynamics(CFD) with dynamic mesh model had been applied in scroll hydraulic pump to obtain its flow field at different leakage clearance. The fluid force on the orbiting scroll, the mass flow rate and the hydraulic efficiency at different leakage clearance were calculated based on the flow field data. The results indicated that when the leakage clearance increased from 0.5mm to 1.5mm, the average pressure, maximum of pressure fluctuation, leakage jet flow velocity, shaft power, cavitation degree decreased and the leakage flow rate increased. If the leakage clearance was 2.0mm, the high pressure discharge fluid flowed through the clearance and led to the increase of the average pressure and fluid force. When the leakage clearance is 1.0mm, the average pressure is far lower than that at the 0.5mm clearance, and the hydraulic efficiency is the highest.

  1. Economic Viability of Pumped-Storage Power Plants Equipped with Ternary Units and Considering Hydraulic Short-Circuit Operation

    Science.gov (United States)

    Chazarra, Manuel; Pérez-Díaz, Juan I.; García-González, Javier

    2017-04-01

    This paper analyses the economic viability of pumped-storage hydropower plants equipped with ternary units and considering hydraulic short-circuit operation. The analysed plant is assumed to participate in the day-ahead energy market and in the secondary regulation service of the Spanish power system. A deterministic day-ahead energy and reserve scheduling model is used to estimate the maximum theoretical income of the plant assuming perfect information of the next day prices and the residual demand curves of the secondary regulation reserve market. Results show that the pay-back periods with and without the hydraulic short-circuit operation are significantly lower than their expected lifetime and that the pay-back periods can be reduced with the inclusion of the hydraulic short-circuit operation.

  2. Fault Diagnosis for Hydraulic Oil Pump Vehicle Based on Fuzzy Theory%基于模糊理论的液压油泵车故障诊断

    Institute of Scientific and Technical Information of China (English)

    张来丰; 朱张青

    2013-01-01

      针对YYBC-2型液压油泵车的故障诊断需求和现有诊断方法存在的问题,本文基于模糊理论,设计了对油泵车液压系统的故障诊断系统,给出了具体实现方法。最后,通过诊断实例证明了本文方法的有效性。%According to the requirement of fault diagnosis for YYBC-2 hydraulic oil pump vehicle and the existing problems, fault diagnosis for hydraulic system of hydraulic oil pump vehicle is presented based on fuzzy theory, and the method to accomplish fault detection is discussed. Final y hydraulic system of YYBC-2 hydraulic oil pump vehicle is studied to explain that the fault diagnosis based on fuzzy theory is effective.

  3. Hydraulic pump common fault analysis and elimination method%液压泵常见故障分析及排除方法

    Institute of Scientific and Technical Information of China (English)

    杨秀荣

    2013-01-01

      液压泵是液压系统中动力元件,相当于人的“心脏”,当液压泵出现故障后液压系统油液系统将无法正常工作。本文分别就三种液压泵对其常见的故障及排除方法进行了探讨。%The hydraulic pump is a hydraulic dynamic component in the system,the equivalent of a man’s\\“heart\\”,when the hydraulic system of hydraulic pump fault occurs after the oil system will not work properly.This paper has three kinds of hydraulic pump for the common failures and troubleshooting methods are discussed in this paper.

  4. Force Balance Analysis Calculation of Downhole Hydraulic Piston Pump%井下水力活塞泵力平衡分析计算

    Institute of Scientific and Technical Information of China (English)

    刘乾义; 郭庆平

    2012-01-01

    The structure and working principle of hydraulic piston pumps is introduced* analysis and calculation of its effective displacement pump and hydraulic motor displacement, and the actual displacement and rated discharge capacity were made. The force balance equation for hydraulic piston pump was established. The P/E values were computed to obtain friction losses, which provided a basis for design and application of hydraulic piston pumps.%介绍了水力活塞泵的结构及工作原理,分析计算了其液马达排量和泵的有效排量、实际排量及额定排量,建立了水力活塞泵力平衡方程,计算得到摩阻损失和P/E值,为水力活塞泵的设计应用提供依据.

  5. Research on Power Recycling Test Method of Integrative Hydraulic Pump and Motor%联体泵马达功率回收试验方法研究

    Institute of Scientific and Technical Information of China (English)

    郭刘洋; 刘俊; 唐守生; 郭杨浏

    2013-01-01

    The experimental method for the integrative hydraulic pump and motor was researched. The power recycling theory of hydraulic pump was analyzed. According to character of the integrative hydraulic pump and motor,the test method for the integrative hydraulic pump and motor power recycling was defined. The formula to calculate volumetric efficiency was deduced. The power recycling test result is assist to analyze volumetric efficiency,meanwhile,to verify the fundamental performance of the integrative hydraulic pump and motor. Additionally,the test result proves that the integrative hydraulic pump and motor power recycling test method is feasible.%  针对联体泵马达的试验方法进行研究,分析液压泵的功率回收试验原理,根据联体泵马达的结构特点,确定了联体泵马达功率回收试验方法,并推导出容积效率计算公式;通过功率回收试验,对联体泵马达的容积效率进行了测试,验证了泵马达的基本性能,也证实了功率回收方法的有效性和可行性。

  6. PUMPS

    Science.gov (United States)

    Thornton, J.D.

    1959-03-24

    A pump is described for conveving liquids, particure it is not advisable he apparatus. The to be submerged in the liquid to be pumped, a conduit extending from the high-velocity nozzle of the injector,and means for applying a pulsating prcesure to the surface of the liquid in the conduit, whereby the surface oscillates between positions in the conduit. During the positive half- cycle of an applied pulse liquid is forced through the high velocity nozzle or jet of the injector and operates in the manner of the well known water injector and pumps liquid from the main intake to the outlet of the injector. During the negative half-cycle of the pulse liquid flows in reverse through the jet but no reverse pumping action takes place.

  7. 液压泵性能测试实验台设计%Design of Performance Test Bench for Hydraulic Pump

    Institute of Scientific and Technical Information of China (English)

    郑明辉; 江吉彬; 郭熛

    2011-01-01

    Hydraulic pump as hydraulic system's power part, is one of important parts of engineering machinery product. The hydraulic pump performance test bench is the necessary device for hydraulic pump product quality examination which is the main safe guard of pump product quality. A hydraulic pump performance test bench was designed. The composition, working principle and char acteristics of the hydraulic system were introduced. Data test and analysis were carried on.%液压泵作为液压系统的动力元件,是工程机械产品的重要部件之一.液压泵性能测试实验台是进行液压泵产品质量检测的必要设备,是泵产品质量监控的主要保障.设计了液压泵性能测试实验台,介绍液压系统组成、工作原理和特点,并进行了数据测试及分析.

  8. Fault Diagnosis of a Hydraulic Pump Based on the CEEMD-STFT Time-Frequency Entropy Method and Multiclass SVM Classifier

    Directory of Open Access Journals (Sweden)

    Wanlin Zhao

    2016-01-01

    Full Text Available The fault diagnosis of hydraulic pumps is currently important and significant to ensure the normal operation of the entire hydraulic system. Considering the nonlinear characteristics of hydraulic-pump vibration signals and the mode mixing problem of the original Empirical Mode Decomposition (EMD method, first, we use the Complete Ensemble EMD (CEEMD method to decompose the signals. Second, the time-frequency analysis methods, which include the Short-Time Fourier Transform (STFT and time-frequency entropy calculation, are applied to realize the robust feature extraction. Third, the multiclass Support Vector Machine (SVM classifier is introduced to automatically classify the fault mode in this paper. An actual hydraulic-pump experiment demonstrates the procedure with a complete feature extraction and accurate mode classification.

  9. Hydraulic Calculation Method for the Fluid Delivery System of Centrifugal Pump%离心泵流体输送系统水力计算方法

    Institute of Scientific and Technical Information of China (English)

    徐宏斌

    2001-01-01

    简述离心泵和管路的特性,介绍离心泵流体输送管路系统的水力计算方法,以及如何确定泵的安装高度。%The characteristics of centrifugal pump and pipeline are brieflyelaborated. The hydraulic calculation method for fluid delivery pipeline system of centrifugal pump and the method of determining the pump installation height are introduced.

  10. An Analytical Solution of Hydraulic Head due to an Oscillatory Pumping Test in a Confined, Unconfined or Leaky Aquifer

    Science.gov (United States)

    Huang, C. S.; Yeh, H. D.

    2014-12-01

    This study builds a mathematical model for three-dimensional (3D) transient hydraulic head induced by an oscillatory pumping test in a confined, unconfined or leaky aquifer. The aquifers are of a rectangular shape where the four sides are under the Robin conditions. The 3D flow governing equation with a line sink term representing a vertical well is employed. The sink term has a cosine function for the oscillatory pumping. A general equation describing the head on the top of the three kinds of aquifers is considered. The analytical head solution of the model is derived by the direct Fourier method and the double-integral transform and in terms of a double series with fast convergence. With the aid of the solution, we have found that the vertical component of flow vanishes when Kv d2/(KhD2) > 1 where Kh and Kv are aquifer's hydraulic conductivities, respectively, D is aquifer's thickness, and d is a distance measured from the pumping well. Under the condition, temporal head distributions predicted by the present solution agree with those predicted by solutions developed based on two-dimensional flow by most previous researches.

  11. EXPERIMENTAL RESEARCH FOCUSED ON YIELDS OF LINEARE HYDRAULIC MOTORS USED TO DRIVE THE BOTTOM PUMPS

    Directory of Open Access Journals (Sweden)

    Petre SĂVULESCU

    2011-07-01

    Full Text Available This paper presents the authors’s concerns for determining the functional parameters and its yieldsfor a linear hydraulic engine with double effect. Functional parameters are determined both at unloadedrunning and loaded running of the linear hydraulic motor. The yields was determined on loaded running.

  12. EXPERIMENTAL RESEARCH FOCUSED ON YIELDS OF LINEARE HYDRAULIC MOTORS USED TO DRIVE THE BOTTOM PUMPS

    OpenAIRE

    Petre SĂVULESCU

    2011-01-01

    This paper presents the authors’s concerns for determining the functional parameters and its yieldsfor a linear hydraulic engine with double effect. Functional parameters are determined both at unloadedrunning and loaded running of the linear hydraulic motor. The yields was determined on loaded running.

  13. THE MEANING OF INSULIN PUMPE THERAPY TO ADULT PATIENTS WITH TYPE 1 DIABETES

    DEFF Research Database (Denmark)

    Nissen, Heidi; Aagaard, Hanne

    and meaningfulness in relation to diabetes self-care and self-management. The bolus guide, as a rather new feature, seem to play an important role. Conclusion: Based on The Shifting Perspectives Model of Chronic Illness, we concluded that a well established insulin pump therapy lead to changing the patients......Background: Insulin pump therapy is an increasing field. Studies have documented a clinical relevant decrease in HbA1c, especially among adults type 1 diabetes patients with initial high HbA1c. However, only few studies investigate the lived experience with and the meaning of the insulin pump...... therapy in adulthood. Aim: The study explore the lived experiences and the meaning of insulin pump therapy in adulthood. Method: The study is based on a phenomenological – hermeneutic approach. Four adult type 1 diabetes patients were interviewed about their insulin pump therapy. The interviews were based...

  14. THE MEANING OF INSULIN PUMPE THERAPY TO ADULT PATIENTS WITH TYPE 1 DIABETES

    DEFF Research Database (Denmark)

    Nissen, Heidi; Aagaard, Hanne

    Background: Insulin pump therapy is an increasing field. Studies have documented a clinical relevant decrease in HbA1c, especially among adults type 1 diabetes patients with initial high HbA1c. However, only few studies investigate the lived experience with and the meaning of the insulin pump...... therapy in adulthood. Aim: The study explore the lived experiences and the meaning of insulin pump therapy in adulthood. Method: The study is based on a phenomenological – hermeneutic approach. Four adult type 1 diabetes patients were interviewed about their insulin pump therapy. The interviews were based...... according to common sense. The third step brings in a theoretical understanding. The findings from the analyze were discussed before we reached a conclusion. Results: The preliminary findings suggested that insulin pump therapy can lead the patients towards an increased comprehensibility, manageability...

  15. BASIC FLOW PATTERNS AND OPTIMUM HYDRAULIC DESIGN OF A SUCTION BOX OF PUMPING STATION

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A numerical method based on 3-D turbulence flow was applied to simulate the flow pattern in suction boxes of six different types.In light of the computational results, the basic flow patterns in the boxes were revealed and a theoretical method to optimize hydraulically design of the suction box is developed.The box geometrical parameters, which influence the flow pattern in the box, could be optimized.The optimum criteria for the hydraulic design of the suction boxes of six types established, respectively.Furthermore, a summarization is given here based on the classification of the basic flow patterns in order to systematically understand the hydraulic design of suction boxes.

  16. Evaluating the feasibility of hydraulic and physical barriers at contaminated sites by means of multicriteria analysis

    Directory of Open Access Journals (Sweden)

    Andrea Gigliuto

    2014-06-01

    Full Text Available Controlling contaminant plumes in groundwater using pump and treat or hydraulic and physical barriers is a common practice to contain and reduce solute contaminants in remediation activities. Recent evolution in engineering techniques also allowed to extend the number of solutions that can be designed and set in practice. As such, the decision-making process assumes great importance in leading the selection of the best suitable technology for a certain case study. This process has to take into account technical, environmental and socioeconomic factors. This paper presents the results of a research project aimed at defining a multi-criteria procedure analysis to support the decision-making process in the barrier technology selection, taking into account technical, economic, social and environmental factors. A multi-criteria analysis methodology has been defined to provide a quantitative tool to guide the selection of the best suitable technology concerning a specific case. The methodology was applied to a real case, selected from many case studies based on data availability and quality, in order to verify the effectiveness of the procedure in evaluating the alternative selections and to highlight the differences between the results of the multi-criteria analysis and the real engineers choices. A sensitivity analysis was performed to analyze the influence of each criterion on the final result of the study. With this paper we aim to start a discussion to deepen the decision making process, in order to develop methodologies allowing to chose the best solution without subjective evaluations.

  17. Designing an Electro-Hydraulic Control Module for an Open-Circuit Variable Displacement Pump

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen; Andersen, Torben Ole; Hansen, Michael Rygaard

    2005-01-01

    , in the form of an electric control signal, under varying working conditions, when having access to engine speed and actual pump pressure. The paper presents a model of both the pump and the control module, along with design considerations on which linear controllers are developed for a worst point...

  18. 浅谈复合式高低压缸液力端在四缸试压泵中的应用%On Application of Compound High and Low Pressure Cylinder Hydraulic Side in the Four Cylinder Hydraulic Test Pump

    Institute of Scientific and Technical Information of China (English)

    蒋金泉

    2014-01-01

    复合式高低压缸液力端,是将泵体上两平行的复合缸分别与一根大小直径的阶梯柱塞配合,形成大流量低压缸和小流量高压缸,解决了现有四缸往复式试压泵存在的问题。%Compound high and low pressure cylinder hydraulic side means to match the two parallel composite cylinder on the pump body, respectively with ladder plunger with big diameter on one side and small diameter on the other side, forming large flow low pressure cylinder and small flow high pressure cylinder, which has solved the existing problems of four cylinder reciprocating hydraulic test pump.

  19. The depth and pitch control of submarines based on the pump-hydraulic servo

    Directory of Open Access Journals (Sweden)

    XU Chao

    2017-03-01

    Full Text Available This study aims to research submarine motion control features in different conditions and com-plex environments in order to solve the problem of actual submarine control and apply it to building an actu-al hydraulic control platform. The paper focuses on the vertical motion of submarines, designs a fast termi-nal sliding mode control algorithm and analyzes the data using the combined simulation and experiment method to study the robustness and reliability of a submarine's vertical motion control system for hydraulic and control. At the same time, the simulation and experiment results analyze the hysteresis and oscillation of the hydraulic steering gear, and effectively reduce the chattering that may be caused by sliding mode variable structure control. This system can be used in simulations to solve the problems of new submarine control characteristics.

  20. A Design for Wind Lubrication of Hydraulic Lubrication Pump%一种用于风电润滑的液动润滑泵设计

    Institute of Scientific and Technical Information of China (English)

    周益; 臧铁钢; 高志朋; 雷晓光

    2012-01-01

    The design for a wind turbine hydraulic lubrication pump, this paper expounds the working principle, features and related function, this pump adopts hydraulic drive way, improve the lubrication pump outlet pressure, pumping performance and reliability. Finally, the control system design, realization sensing monitoring, automatic alarm, historical records and inquires the related functions.%设计了一种用于风力发电设备的液动润滑泵,阐述了其工作原理、主要特点以及相关功能.该泵采用液压方式驱动,提高了润滑泵的出口压力、泵送性能及可靠性.设计了控制系统,实现传感检测、自动报警、历史记录与查询等相关功能.

  1. Numerical Research on Hydraulically Generated Vibration and Noise of a Centrifugal Pump Volute with Impeller Outlet Width Variation

    Directory of Open Access Journals (Sweden)

    Houlin Liu

    2014-01-01

    Full Text Available The impeller outlet width of centrifugal pumps is of significant importance for numbers of effects. In the paper, these effects including the performance, pressure pulsations, hydraulically generated vibration, and noise level are investigated. For the purpose, two approaches were used to predict the vibration and sound radiation of the volute under fluid excitation force. One approach is the combined CFD/FEM analysis for structure vibration, and then the structure response obtained from the FEM analysis is treated as the boundary condition for BEM analysis for sound radiation. The other is the combined CFD/FEM/BEM coupling method. Before the numerical methods were used, the simulation results were validated by the vibration acceleration of the monitoring points on the volute. The vibration and noise were analyzed and compared at three flow conditions. The analysis of the results shows that the influences of the sound pressure of centrifugal pumps on the structure appear insignificant. The relative outlet width b2* at nq(SI = 26.7 in this paper should be less than 0.06, based on an overall consideration of the pump characteristics, pressure pulsations, vibration and noise level.

  2. New JSME standard S008 “Performance Conversion Method for Hydraulic Turbines and Pump-Turbines”

    Science.gov (United States)

    Nakanishi, Y.; Kitahora, T.; Suzuki, S.; Suzuki, T.; Sugishita, K.; Suzuki, R.; Tani, K.

    2016-11-01

    JSME Standard S008 “Performance Conversion Method for Hydraulic Turbines and Pump-Turbines” is now being revised and will be published in 2016. This new revision follows the main theory of previous version S008-1999. It enables us to convert the performance of each flow passage component of spiral case, stay vane, guide vane, runner and draft tube of model turbines and pump-turbines to that of prototypes with one-step calculation. The relevant values needed for the performance conversion, e.g. dimension factor, flow velocity factor, relative scalable loss of components δ ECO , etc. are newly organized as functions of specific speeds of turbines and pump-turbines using polynomial expressions. Additional data for high specific speed turbines are included. The resultant factors for conversion of the specific energy efficiency scale factor F E , the discharge efficiency scale factor F Q and the power efficiency scale factor F T are determined by considering friction coefficient ratio for prototype to the model.

  3. Hydraulic testing of intravascular axial flow blood pump designs with a protective cage of filaments for mechanical cavopulmonary assist.

    Science.gov (United States)

    Kapadia, Jugal Y; Pierce, Kathryn C; Poupore, Amy K; Throckmorton, Amy L

    2010-01-01

    To provide hemodynamic support to patients with a failing single ventricle, we are developing a percutaneously inserted, magnetically levitated axial flow blood pump designed to augment pressure in the cavopulmonary circulation. The device is designed to serve as a bridge-to-transplant, bridge-to-recovery, bridge-to-hemodynamic stability, or bridge-to-surgical reconstruction. This study evaluated the hydraulic performance of three blood pump prototypes (a four-bladed impeller, a three-bladed impeller, and a three-bladed impeller with a four-bladed diffuser) whose designs evolved from previous design optimization phases. Each prototype included the same geometric protective cage of filaments, which stabilize the rotor within the housing and protect the housing wall from the rotating blades. All prototypes delivered pressure rises over a range of flow rates and rotational speeds that would be sufficient to augment hemodynamic conditions in the cavopulmonary circulation. The four-bladed impeller outperformed the two remaining prototypes by >40%; this design was able to generate a pressure rise of 4-28 mm Hg for flow rates of 0.5-10 L/min at rotational speeds of 4,000-7,000 RPM. Successful development of this blood pump will provide clinicians with a feasible therapeutic option for mechanically supporting the failing Fontan.

  4. REPAIR OF GEAR-TYPE PUMPS FOR HYDRAULIC SYSTEMS OF CONSTRUCTION MACHINES

    OpenAIRE

    Posviatenko, Ye; Kropivniy, V.; Posviatenko, N.; Rousskykh, V.

    2007-01-01

    Investigation into resource-saving technology of repair of gear-type pumps by contact welding -on some wear-resistant composite sintered powders on the top of teeth with further thermal-cycle treatment has been described.

  5. Optimization Design of a Double-Channel Pump by Means of Orthogonal Test, CFD, and Experimental Analysis

    Directory of Open Access Journals (Sweden)

    Binjuan Zhao

    2014-07-01

    Full Text Available A new approach to optimizing a double-channel pump was presented, based on combined use of orthogonal test, computational fluid dynamics (CFD, and experimental analysis. First, a preliminary pump was designed according to design specifications, implementing the traditional design method. Later, a standard L9 (34 orthogonal table including 9 representative design schemes was implemented to find the best parameter combination for the impeller of the pump. Reynolds averaged Navier-Stokes equations accompanied by Smith modified k-ε turbulence model were solved to obtain the inner flow fields of the pump as well as its hydraulic performance for each design scheme. The optimized design scheme was obtained after range analysis. Finally, CFD analyses and experiments were carried out to evaluate the optimized design. The results show that the characteristics of the optimized pump were obviously improved, and the simulated pump head and efficiency increased by 3.622% and 9.379%, respectively. This research not only provides an effective way to improve the hydraulic design of double-channel pumps, but also has certain reference value in multiobjectiveoptimization design of other pumps.

  6. McMillan Pumping Station, Washington, D.C.; Hydraulic Model Investigation.

    Science.gov (United States)

    1980-09-01

    from the pump intake, dissipated some of the excessive kinetic energy of inflow, and essentially eliminated adverse effects of secondary crossflow...inside the prototype channel. A headbox in the model simulated the prototype channel and received water from each of the three pumps. The water was...baffled as it entered the headbox , then it was allowed to flow back into the sump through the four h8-in. (prototype) inflow pipes (simulated). Flow

  7. Operation history of hydraulic jet pump on teh Chengbei oil field, China. Chengbei yuden ni okeru haidororikku jet pump no shiyo jisseki

    Energy Technology Data Exchange (ETDEWEB)

    Terao, Yoshihiro; Takagi, Sunao

    1989-11-01

    Changbei oil field in China uses hydraulic jet pump(HJP) to cope with the increase of oil production and increase of water content in the oil field. This paper described the practical result. This pump makes high speed jet by driving fluid, and converts the dynamic energy to pressure energy by decelerating with a diffuser to push up oil. Wellheads damaged by sand friction or near the gas cap were removed. The production from March, 1988 to October increased at the rate of 114kl/day at total 8 wellheads. Heavy oil of API specific gravity of 16 degree could be proved. Since the separation of oil and water was inferior, so that the countermeasures were studied but the cause was not known. Troubles or failures of main body, nozzle and throat of HJP were not occurred. Any effect could not be found at a wellhead of water content exceeding 50 to 60% because only water production increased. Consequently, this process could result the increase of oil production with lower cost and without mechanical failures. 2 refs., 7 figs., 7 tabs.

  8. Autonomously responsive pumping by a bacterial flagellar forest: A mean-field approach

    Science.gov (United States)

    Martindale, James D.; Fu, Henry C.

    2017-09-01

    This study is motivated by a microfluidic device that imparts a magnetic torque on an array of bacterial flagella. Bacterial flagella can transform their helical geometry autonomously in response to properties of the background fluid, which provides an intriguing mechanism allowing their use as an engineered element for the regulation or transport of chemicals in microscale applications. The synchronization of flagellar phase has been widely studied in biological contexts, but here we examine the synchronization of flagellar tilt, which is necessary for effective pumping. We first examine the effects of helical geometry and tilt on the pumping flows generated by a single rotating flagellum. Next, we explore a mean-field model for an array of helical flagella to understand how collective tilt arises and influences pumping. The mean-field methodology allows us to take into account possible phase differences through a time-averaging procedure and to model an infinite array of flagella. We find array separation distances, magnetic field strengths, and rotation frequencies that produce nontrivial self-consistent pumping solutions. For individual flagella, pumping is reversed when helicity or rotation is reversed; in contrast, when collective effects are included, self-consistent tilted pumping solutions become untilted nonpumping solutions when helicity or rotation is reversed.

  9. Dynamic Analysis of Hydraulic Pumping Units%液压抽油机动态特性分析

    Institute of Scientific and Technical Information of China (English)

    李桂喜; 许建中

    2001-01-01

    应用机械振动理论,对液压抽油机的动态特性进行了分析。结果表明,液压抽油机在准匀速悬点运动条件下,抽油泵的运动由两部分组成:一是随悬点一起的刚体运动,二是由于悬点支撑位移激发的振动响应,其振动频率为系统的固有频率。适当调整系统参数,抽油泵将出现超冲程现象,这对于提高采油效率将是有益的。在准匀速悬点位移作用下,将引起抽油杆柱的振动,导致杆柱中的动应力。杆柱中的最大振动位移随深度增加量值逐渐增大,最大动应力随深度增加而逐渐减小。最大动应力随深度不是线性变化的,而是为二次函数关系。%The dynamic analysis of hydraulic pumping units was carried out in this paper by using the theory of mechanical vibrations. The house-head movement of the pumping unit is mainly uniform,except the alternation period of upper-and down-strokes.Under the action of the house-head movement,the vibration of the system,the sucker-rod and,furthermore,the dynamic stress will be induced.The results indicate that the movement of the downhole pump includes two parts. One is the movement following the horse-head.The other is the dynamic response excited by the support movement.When the parameters of the system are selected reasonably,over-stroke of the pump will appear.This is because the movement of the hydraulic piston obeys a particular law.The maximum displacement increases,and the maximum dynamic stress decreases with depth.The changing of maximum dynamic stress with depth obeys quadratic law.

  10. Hydraulics of Fuel-Injection Pumps for Compression-ignition Engines

    Science.gov (United States)

    Rothrock, A M

    1932-01-01

    Formulas are derived for computing the instantaneous pressures delivered by a fuel pump. The first derivation considers the compressibility of the fuel and the second, the compressibility, elasticity, and inertia of the fuel. The second derivation follows that given by Sass; it is shown to be the more accurate of the two. Additional formulas are given for determining the resistance losses in the injection tube. Experimental data are presented in support of the analyses. The report is concluded with an application of the theory to the design of fuel pump injection systems for which sample calculations are included.

  11. Breadboard development of a hydraulically coupled free piston engine heat pump compressor

    Science.gov (United States)

    Marusak, T. J.

    1984-11-01

    The free piston Stirling engine (FPSE) was considered as a candidate for a thermally activated heat pump because of its potential for high efficiency coupled with long life and high reliability. The distinguishing features of the FPSE, one moving part and hermatic separation of the power cycle and refrigeration cycle working fluids, makes it ideally suited for a heat pump application. However, two major designs challenges have kept the FPSE in the realm of laboratory rather than product development. These challenges involve: effective control of a tuned resonant system over a wide range of loads and hermatic coupling of the driver and driven mechanical members.

  12. HYDRAULIC SERVO

    Science.gov (United States)

    Wiegand, D.E.

    1962-05-01

    A hydraulic servo is designed in which a small pressure difference produced at two orifices by an electrically operated flapper arm in a constantly flowing hydraulic loop is hydraulically amplified by two constant flow pumps, two additional orifices, and three unconnected ball pistons. Two of the pistons are of one size and operate against the additional orifices, and the third piston is of a different size and operates between and against the first two pistons. (AEC)

  13. Numerical and experimental studies of hydraulic noise induced by surface dipole sources in a centrifugal pump

    Institute of Scientific and Technical Information of China (English)

    刘厚林; 戴菡葳; 丁剑; 谈明高; 王勇; 黄浩钦

    2016-01-01

    The influences of the four different surface dipole sources in a centrifugal pump on the acoustic calculating accuracy are studied in this paper, by using the CFD combined with the Lighthill acoustic analogy methods. Firstly, the unsteady flow in the pump is solved based on the large eddy simulation method and the pressure pulsations on the four different surfaces are obtained. The four surfaces include the volute surface, the discharge pipe surface, the inner surface of the pump cavity, and the interfaces between the impeller and the stationary parts as well as the outer surface of the impeller. Then, the software Sysnoise is employed to interpolate the pressure fluctuations onto the corresponding surfaces of the acoustic model. The Fast Fourier Transform with a Hanning window is used to analyze the pressure fluctuations and transform them into the surface dipole sources. The direct boundary element method is applied to calculate the noise radiated from the dipole sources. And the predicted sound pressure level is compared with the experi- mental data. The results show that the pressure fluctuations on the discharge pipe surface and the outer surface of the impeller have little effect on the acoustic simulation results. The pressure pulsations on the inner surface of the pump cavity play an important role in the internal flow and the acoustic simulation. The acoustic calculating error can be reduced by about 7% through considering the effect of the pump cavity. The sound pressure distributions show that the sound pressure level increases with the growing flow rate, with the largest magnitude at the tongue zone.

  14. Technology and means of a coal seam interval hydraulic fracturing for the seam degassing intensification

    Science.gov (United States)

    Klishin, VI; Opruk, GY; Tatsienko, AL

    2017-02-01

    Interval hydraulic fracturing use for the seam degassing intensification actuality is explained. The known methods of degassing are reviewed. Technological scheme of the interval coal seam hydraulic fracturing implementation is worked out. The equipment to fulfill degassing intensification measures is suggested.

  15. A new hydraulic reciprocating triplex pump for water shutoff and profile control.%SYB─Ⅰ型三缸液压往复式堵水调剖泵

    Institute of Scientific and Technical Information of China (English)

    许建中; 曹和平; 林鹏进; 张志海

    2001-01-01

    Model TDB hydraulic reciprocating duplex pump for water shutoff and profile control operates with large pressure and flow fluctuation. Thereby a new hydraulic reciprocating pump, Model SYB-Ⅰtriplex pump, is developed. The new pump runs with constant flow rate by means of cyclical operation of its three cylinders. There are phases overlapped between adjacent cylinders, so the flow from each cylinder can be compensated. The pump has long stroke, low pumping speed and long service life, therefore it can meet the demand of water shutoff and profile control.%为了克服TDB双缸液压往复泵流量和压力波动大需要流量补偿等不足,研制了SYB—Ⅰ型三缸液压往复式堵水调剖泵。该型泵采用三个液压缸循环工作原理,两个相邻缸之间有运动相位的重叠,使泵在工作时各缸相互补偿,保证了输出流量的恒定。采用两级液压控制自动换向机构,关键元件采用德国生产的专用液压缸筒、TDI系列密封件及GTK系列组合密封,使泵密封件工作寿命达2×107个周期。泵长冲程、低冲次的工作特性赋予了易损件寿命长的特点,加之泵的制造成本仅为7~8万元,从性能价格比上具有一定的竞争优势。

  16. Energy-saving Study of Excavator Based on Hydraulic Pump Efficiency%基于液压泵效率的挖掘机节能研究

    Institute of Scientific and Technical Information of China (English)

    吴文海; 杨宇澜; 刘桓龙; 王国志

    2014-01-01

    For the work characteristics of the volume adjustable hydraulic pump,its control and working principle in the hydrau-lic excavator were analyzed. And as a basis,the simulation model of a volume adjustable pump and a hydraulic excavator machine was established. The simulation results show that the discharge ratio of the volume adjustable pump is an important control parameter which can achieve a greater impact on the efficiency of a hydraulic pump. When the excavator is in the fine operation phase,a reducer is used to adjust the pump speed,and the increase of the discharge ratio can improve the efficiency of the pump,so the fuel consumption is decreased by 16.5% which improves the overall fuel efficiency.%针对变量液压泵的工作特点,分析了其在液压挖掘机中控制和工作原理,并以此为基础建立了变量泵以及液压挖掘机整机的仿真模型。仿真结果表明:变量泵的排量比是对挖掘机中液压泵效率影响较大且可实现控制的一个重要参数,在挖掘机精细作业时采用减速机调节泵的转速,适当增大泵的排量比能提高泵的效率,使油耗量下降了16.5%,提高了整机的燃油效率。

  17. Improving the Hydraulic Efficiency of Centrifugal Pumps through Computational Fluid Dynamics Based Design optimization

    Directory of Open Access Journals (Sweden)

    Abdellah Ait moussa

    2014-08-01

    Full Text Available The design and optimization of turbo machine impellers such as those in pumps and turbines is a highly complicated task due to the complex three-dimensional shape of the impeller blades and surrounding devices. Small differences in geometry can lead to significant changes in the performance of these machines. We report here an efficient numerical technique that automatically optimizes the geometry of these blades for maximum performance. The technique combines, mathematical modeling of the impeller blades using non-uniform rational B-spline (NURBS, Computational fluid dynamics (CFD with Geometry Parameterizations in turbulent flow simulation and the Globalized and bounded Nelder-Mead (GBNM algorithm in geometry optimization.

  18. 竖井贯流泵装置流道水力性能分析%Hydraulic Performance Analysis on the Flow Passage of Shaft Tubular Pump System

    Institute of Scientific and Technical Information of China (English)

    杨雪林; 黄毅; 陈国标

    2012-01-01

    针对竖井贯流泵装置中,进、出水流道水力损失所占比重较大的问题,通过分析泵装置流道的三维数值模拟结果,对流道型线进行了优化设计,获得了水力性能较好的型线方案。结合模型试验结果,表明流道型线优化后的水泵装置效率较高,具有较好的水力性能。%According to the facts that the hydraulic losses of inlet and outlet passage takes a large proportion in shaft tubular pump sets, 3D numerical simulation of pump sets'passage is analyzed, the passage shape is optimally designed and the passage shape with better hydraulic performance is obtained. Comparing with pump model device experiment, the pump sets with optimal passage shape is of high efficiency and good hydraulic performance.

  19. Dynamically balanced, hydraulically driven compressor/pump apparatus for resonant free piston Stirling engines

    Science.gov (United States)

    Corey, John A.

    1984-05-29

    A compressor, pump, or alternator apparatus is designed for use with a resonant free piston Stirling engine so as to isolate apparatus fluid from the periodically pressurized working fluid of the Stirling engine. The apparatus housing has a first side closed by a power coupling flexible diaphragm (the engine working member) and a second side closed by a flexible diaphragm gas spring. A reciprocally movable piston is disposed in a transverse cylinder in the housing and moves substantially at right angles relative to the flexible diaphragms. An incompressible fluid fills the housing which is divided into two separate chambers by suitable ports. One chamber provides fluid coupling between the power diaphragm of the RFPSE and the piston and the second chamber provides fluid coupling between the gas spring diaphragm and the opposite side of the piston. The working members of a gas compressor, pump, or alternator are driven by the piston. Sealing and wearing parts of the apparatus are mounted at the external ends of the transverse cylinder in a double acting arrangement for accessibility. An annular counterweight is mounted externally of the reciprocally movable piston and is driven by incompressible fluid coupling in a direction opposite to the piston so as to damp out transverse vibrations.

  20. Mixed Lubrication Simulation of Hydrostatic Spherical Bearings for Hydraulic Piston Pumps and Motors

    Science.gov (United States)

    Kazama, Toshiharu

    Mixed and fluid film lubrication characteristics of hydrostatic spherical bearings for swash-plate-type axial piston pumps and motors are studied theoretically under non-steady-state conditions. The basic equations incorporating interference and contact of surface roughness are derived fundamentally through combination of the GW and PC models. Furthermore, a programming code that is applicable to the caulked-socket-type and open-socket-type bearings is developed. Effects of caulking, operating conditions, and the bearing dimension on the motion of the sphere and tribological performance of the bearings are examined. Salient conclusions are the following: The sphere's eccentricity increases in the low supply pressure period. The time-lag of the load change engenders greater motion of the sphere. Caulking of the bearing socket suppresses the sphere's motion. The bearing stiffness increases and power loss decreases for smaller recess angles. Minimum power loss is given under the condition that the bearing socket radius nearly equals the equivalent load radius.

  1. Hydraulic performance improvement of the bidirectional pit pump installation based on CFD

    Science.gov (United States)

    Chen, H. X.; Zhou, D. Q.

    2013-12-01

    At present, the efficiency of bidirectional pit pump installation with lift under 2m is still low because of lack of research on it in the past. In the paper, the CFD numerical method and experimental test were applied to study flow characteristic of bidirectional pit pump installation under positive and reverse condition. Through changing airfoil type and position of blade and stay vane, the comprehensive performance of improved model were obtained by calculating many different models. The results showed that when improved model is obtained with type A runner with 4 blades that is 0.7D away from pit exit and unsymmetrical guide vane 0.25dh which away from the impeller outlet, and the flow pattern of the improved solution is steady with high efficiency. Compared with the original scheme, the efficiency of positive and reverse design condition reach to 67.23% and 58.32% respectively, which is increased 6% more than original model on the design condition and 5% on the optimum operating condition, and it achieved the purpose of improvement. According to the runner blade angle of the optimization solution, model synthetic characteristic curve was drawn and internal flow field characteristics was analyzed under optimal positive and reverse conditions. The numerical calculation shows that owing to the lack of stay vane to recycle the energy in outlet runner chamber, the water flow regime is not steady enough in the outlet passage, and that is the main reason for lower efficiency at reverse condition than that at positive condition.

  2. Theoretical Analysis and Bench Tests of a Control-Surface Booster Employing a Variable Displacement Hydraulic Pump

    Science.gov (United States)

    Mathews, Charles W.; Kleckner, Harold F.

    1947-01-01

    The NACA is conducting a general investigation of servo-mechanisms for use in powering aircraft control surfaces. This paper presents a theoretical analysis and the results of bench tests of a control-booster system which employs a variable displacement hydraulic pump. The booster is intended for use in a flight investigation to determine the effects of various booster parameters on the handling qualities of airplanes. Such a flight investigation would aid in formulating specific requirements concerning the design of control boosters in general. Results of the theoretical analysis and the bench tests indicate that the subject booster is representative of types which show promise of satisfactory performance. The bench tests showed that the following desirable features were inherent in this booster system: (1) No lost motion or play in any part of the system; (2) no detectable lag between motion of the contra1 stick and control surface; and (3) Good agreement between control displacements and stick-force variations with no hysteresis in the stick-force characteristics. The final design configuration of this booster system showed no tendency to oscillate, overshoot, or have other undesirable transient characteristics common to boosters.

  3. A Numerical Study on the Improvement of Suction Performance and Hydraulic Efficiency for a Mixed-Flow Pump Impeller

    Directory of Open Access Journals (Sweden)

    Sung Kim

    2014-01-01

    Full Text Available This paper describes a numerical study on the improvement of suction performance and hydraulic efficiency of a mixed-flow pump by impellers. The design of these impellers was optimized using a commercial CFD (computational fluid dynamics code and DOE (design of experiments. The design variables of meridional plane and vane plane development were defined for impeller design. In DOE, variables of inlet part were selected as main design variables in meridional plane, and incidence angle was selected in vane plane development. The verification of the experiment sets that were generated by 2k factorial was done by numerical analysis. The objective functions were defined as the NPSHre (net positive suction head required, total efficiency, and total head of the impellers. The importance of the geometric design variables was analyzed using 2k factorial designs. The interaction between the NPSHre and total efficiency, according to the meridional plane and incidence angle, was discussed by analyzing the 2k factorial design results. The performance of optimally designed model was verified by experiments and numerical analysis and the reliability of the model was retained by comparison of numerical analysis and comparative analysis with the reference model.

  4. Sealing Mechanism and Use of O-ring for Hydraulic Gear Pump%液压齿轮泵中O形圈密封机理和选用

    Institute of Scientific and Technical Information of China (English)

    周亚东

    2015-01-01

    该文对液压齿轮泵中的O形圈的密封机理进行了简要分析,并给出O形圈选用时的一些注意事项。%This article simple analysis sealing mechanism of O-ring which used in Hydraulic Gear Pump, and gives some notes of how to choose O-ring.

  5. Degradation feature extraction of the hydraulic pump based on high-frequency harmonic local characteristic-scale decomposition sub-signal separation and discrete cosine transform high-order singular entropy

    Directory of Open Access Journals (Sweden)

    Jian Sun

    2016-07-01

    Full Text Available Hydraulic pump degradation feature extraction is a key step of condition-based maintenance. In this article, a novel method based on high-frequency harmonic local characteristic-scale decomposition sub-signal separation and discrete cosine transform high-order singular entropy is proposed. In order to reduce noises and other disturbances, the vibration signal is processed by the local characteristic-scale decomposition modified by the high-frequency harmonic. Sub-signal with sensitive information is obtained by blind source separation of the selected intrinsic scale components. Furthermore, the discrete cosine transform high-order spectral analysis algorithm is proposed to extract singular entropies of Shannon and Tsallis to be the degradation features of the hydraulic pump. Analysis of the hydraulic pump experiment demonstrates that the proposed method is feasible and effective in indicating the performance degradation of the hydraulic pump.

  6. 在水力除焦中采用变转速除焦水泵的探讨%Study on variable speed decoking pump in hydraulic decoking

    Institute of Scientific and Technical Information of China (English)

    张欣

    2011-01-01

    Fixed-speed decoking jet pumps are widely used in present hydraulic decoking process. Frequent start up, shutdown and fixed discharge pressure of the pumps often result in problems of impacting, vibration and excessive coke powder production. A hydraulic decoking technology in which variable speed decoking jet pumps are used is introduced. In the technology, variable speed equipment such as hydraulic coupling or variable frequency device is applied to unload the start-up of decoking jet pump, smoothly adjust the speed and control the decoking water pressure as required and perform decoking operation more conveniently and efficiently. The application of the technology has improved the flexibility of the decoking jet pumps and reliability of related decoking equipment, etc and reduced the coke powder production. The economics of the unit operation is improved.%在目前的水力除焦技术中普遍采用定转速除焦水泵,泵需要频繁启停且出口压力恒定不变,因而带来冲击、振动以及产生焦粉过多等问题.为解决此问题,介绍了一种采用变转速除焦水泵的技术,即通过液力偶合器或变频器等调速装置驱动,实现除焦水泵的无负荷启动、平滑调速,进而按需调节除焦水压力.结果表明:该技术使操作更灵活优化,并提高相关设备长周期运行的可靠性、减少焦粉的产生;可逐步升速,实现“回流-预充-钻孔”的操作程序,更经济节能.

  7. Centrifugal pumps

    CERN Document Server

    Gülich, Johann Friedrich

    2014-01-01

    This book gives an unparalleled, up-to-date, in-depth treatment of all kinds of flow phenomena encountered in centrifugal pumps including the complex interactions of fluid flow with vibrations and wear of materials. The scope includes all aspects of hydraulic design, 3D-flow phenomena and partload operation, cavitation, numerical flow calculations, hydraulic forces, pressure pulsations, noise, pump vibrations (notably bearing housing vibration diagnostics and remedies), pipe vibrations, pump characteristics and pump operation, design of intake structures, the effects of highly viscous flows, pumping of gas-liquid mixtures, hydraulic transport of solids, fatigue damage to impellers or diffusers, material selection under the aspects of fatigue, corrosion, erosion-corrosion or hydro-abrasive wear, pump selection, and hydraulic quality criteria. As a novelty, the 3rd ed. brings a fully analytical design method for radial impellers, which eliminates the arbitrary choices inherent to former design procedures. The d...

  8. A comparative study of Cr-X-N (X=Zr, Si) coatings for the improvement of the low-speed torque efficiency of a hydraulic piston pump

    Science.gov (United States)

    Hong, Yeh-Sun; Lee, Sang-Yul

    2008-02-01

    The internal parts of hydraulic pumps operating at variable speed should be protected from insufficient lubrication. The axial piston type pumps employ a steel-base cylinder barrel rotating on a soft bronze valves plate with a slide contact, where the insufficient lubrication of these components can cause rapid wear of the valve plate and increase the friction loss. In this study, the cylinder barrel surface was deposited with CrZrN coatings, which were expected to improve the tribological contact with a valve plate under low-speed mixed lubrication conditions. Its effect on the improvement of the low-speed torque efficiency of a hydraulic piston pump was investigated and compared with that from the CrSiN coating. The coated cylinder barrels showed much lower friction coefficients and wear rates of the valve plates than the uncoated plasma-nitride one. In particular, the CrZrN coatings revealed better performance than the CrSiN coatings. By representing the improvement in the torque efficiency of the whole pump based upon the degree of the friction coefficient reduction, the CrZrN coatings exhibited approximately a 0.35% higher improvement at 300 bar and 100 rpm than CrSiN coatings. The possible failure modes of the coatings coated on the barrel were sugested and the microstructures of the coatings seemed to have a strong effect on the film failure mode.

  9. Increase of economy of torque flow pump with high specific speed

    Science.gov (United States)

    Gusak, A. G.; Krishtop, I. V.; German, V. F.; Baga, V. N.

    2017-08-01

    Torque flow pumps are widely spread types of energy machines, which are used in majority of modern branches of industry for pumping of dirty media. The main task of researchers of torque flow pumps is increase of such pumps effectiveness for higher feed. Hydraulic losses for torque flow pumps are caused by working process of such pumps and are inevitable. Decrease of losses can be obtained by means of optimization of hydraulic flow part geometry. Modern approach to design of pump outlet introduces new constructive solutions which can increase economy of torque flow pumps. The aim of this research is increase of economy of torque flow pumps by means of application of spatial outlet and investigation of its geometry on pump characteristics. Analytical and numerical methods of liquid flow research for hydraulic flow part of torque flow pump were used in this paper. Moreover, influence of hydraulic flow part geometry of different designs of “Turo” type torque flow pumps outlets on pump characteristics was investigated. Numerical research enabled to study process of energy transfer of torque flow pump and evaluate influence of geometrical dimensions of spatial spiral outlet on its characteristics. Besides numerical research confirmed introduced regularity of peripheral velocity distribution in outlet. Velocity moment distribution in outlet was obtained during implementation of numerical research. Implemented bench tests of torque flow pump prototypes enabled to obtain real characteristics of pump and confirm effectiveness of spatial geometry of outlet application for such pump.

  10. Heat pump applications and water heating by means of solar collectors. Waermepumpenanwendungen und Wasserwaermung mit Sonnenkollektoren

    Energy Technology Data Exchange (ETDEWEB)

    Szokody, G.

    1990-01-15

    About 25 to 30% of all newly constructed single-family houses in Switzerland are equipped with heat pump systems. This increasing attractivity is partly due to new techniques, e.g. microprocessor control, as well as to higher component efficiencies, a more efficient heat exchange technology, and to the compactness of systems. Active solar energy conversion, i.e. by means of solar collectors, is another technique which is predominantly applied for water heating in single-family buildings. Public investments in this field are scarce. (BWI).

  11. 液压泵性能检测实验台设计及检测分析%Design of Performance Test System for Hydraulic Pump

    Institute of Scientific and Technical Information of China (English)

    武金良; 赵坚; 于浩

    2016-01-01

    液压泵是液压系统中的动力元件,其性能的优劣直接影响到液压系统的工作。因此,对其进行性能检测十分必要。引入绿色设计理念,设计了液压泵性能检测系统,并进行了实测验证,保证了系统检测数据的精度,提高了检测效率。%The hydraulic pump is the drive component of the hydraulic system, its performance will directly affect the normal work of hydraulic system. Therefore, it is very necessary to test its performance. The concept of green design was introduced, the hy⁃draulic pump performance test system was designed, and the verification was completed. So the accuracy of the system is guaranteed, and its detecting efficiency is improved obviously.

  12. Hydraulic design of a double suction blood pump%一种双吸式血液泵水力设计

    Institute of Scientific and Technical Information of China (English)

    田爱民; 庄保堂; 朱雷; 罗先武; 许洪元

    2011-01-01

    The flow in pumps for open-heart and artificial heart units must be carefully optimized for the blood flow.The steady state three-dimensional turbulent flow inside a double suction blood pump was analyzed by solving the RANS equations with the SST k-ω turbulence model.The flow features in the blood pump were analyzed to optimize the design of the hydraulic components including the impeller and volute casing and the effects of various designs on the pump operating.The flow passage near the casing tongue has larger local wall shear stresses that may damage the blood cells,damage in the pump.The pump hydraulic efficiency can be improved by increasing the volute casing section area and a larger impeller vane exit angle will increase the pump head.Flow separation and its effect on pump performance can be controlled by a radial bladed impeller with a vane exit angle of 90°.The wall shear stresses for all designs were 20~26 Pa,less than the critical value for blood cell damage.%为了更好地满足体外循环装置和人工心脏的运行要求,该文采用RANS方法和SSTk-ω湍流模型对一种双吸式血液泵进行了三维定常湍流计算;在详细分析血液泵内部流动特征的基础上,对泵的水力部件如叶轮及压水室进行了设计优化,并探讨了各种设计对血液泵主要运行参数的影响。结果表明:压水室隔舌附近的流道容易出现较大的局部壁面剪切应力,是泵内血细胞容易受到损伤的危险区域;适当增大压水室断面面积有利于提高泵的水力效率;选择较大的叶片出口安放角时血液泵可获得较高的扬程,但采用径向叶片叶轮(出口叶片安放角为90°)时须设法控制流

  13. Estimating mechanical blood trauma in a centrifugal blood pump: laser Doppler anemometer measurements of the mean velocity field.

    Science.gov (United States)

    Pinotti, M; Paone, N

    1996-06-01

    A laser Doppler anemometer (LDA) was used to obtain the mean velocity and the Reynolds stress fields in the inner channels of a well-known centrifugal vaneless pump (Bio-pump). Effects of the excessive flow resistance against which an occlusive pump operates in some surgical situations, such as cardiopulmonary bypass, are illustrated. The velocity vector field obtained from LDA measurements reveals that the constraint-forced vortex provides pumping action in a restricted area in the core of the pump. In such situations, recirculating zones dominate the flow and consequently increase the damage to blood cells and raise the risk of thrombus formation in the device. Reynolds normal and shear stress fields were obtained in the entry flow for the channel formed by two rotating cones to illustrate the effects of flow disturbances on the potential for blood cell damage.

  14. Flow to partially penetrating wells in unconfined heterogeneous aquifers: Mean head and interpretation of pumping tests

    Science.gov (United States)

    Dagan, G.; Lessoff, S. C.

    2011-06-01

    A partially penetrating well of length Lw and radius Rw starts to pump at constant discharge Qw at t = 0 from an unconfined aquifer of thickness D. The aquifer is of random and stationary conductivity characterized by KG (geometric mean), σY2 (log conductivity variance), and I and Iv (the horizontal and vertical integral scales). The flow problem is solved under a few simplifying assumptions commonly adopted in the literature for homogeneous media: Rw/Lw ≪ 1, linearization of the free surface condition, and constant drainable porosity n. Additionally, it is assumed that Rw/I and the associated water table equation. The main result of the analysis is that the flow domain can be divided into three zones for : (1) the neighborhood of the well R ≪ I, where = (Qw/LwKA)h0(R, z, tKefuv/nD), with h0 being the zero-order solution pertaining to a homogeneous and isotropic aquifer, KA being the conductivity arithmetic mean, and Kefuv being the effective vertical conductivity in mean uniform flow, (2) an exterior zone R ⪆ I in which ?H? = (Qw/LwKefuh)h0(R?, z, tKefuv/nD), with Kefuh being the horizontal effective conductivity, and (3) an intermediate zone in which the solution requires a few numerical quadratures, not carried out here. The application to pumping tests reveals that identification of the aquifer parameters for homogeneous and anisotropic aquifers by commonly used methods can be applied for the drawdown measured in an observation well of length Low?Iv (to ensure exchange of space and ensemble head averages) in the second zone in order to identify Kefuh, Kefuv, and n. In contrast, the use of the drawdown in the well (first zone) leads to an overestimation of Kefuh by the factor KA/Kefuh.

  15. 泵直接传动式锻造液压机计算机控制%Computer control of forging hydraulic press with pump-direct-drive

    Institute of Scientific and Technical Information of China (English)

    陈柏金; 钟绍辉; 靳龙; 黄树槐

    2001-01-01

    This paper introduces the principle of forging hydraulic pre ss with pump-direct-drive, and presents the architecture of field control networ k and the CNC system. The control method is also discussed in detail.%介绍了泵直接传动的锻造液压机工作原理,对其采用现场控制网络的体系结构和计算机控制系统进行了描述,并对其控制原理、控制策略进行了研究。

  16. 适用于动静压试验的综合液压源的设计%A Multifunctional Pump Station Designed for Dynamic and Static Pressure Hydraulic Tests

    Institute of Scientific and Technical Information of China (English)

    孔炫畅

    2015-01-01

    分析了液压元件动静压试验的测试需求,据此进行了液压泵站的设计。液压泵站液压能由电动泵和手动泵提供,满足不同性质的液压实验需求。实践证明,对于实验类型较多,特别是静压实验较多的场合,综合液压源与常规液压源相比,具有明显优势。%Based on the dynamic and static pressure test requirement of hydraulic components, the pump station is designed. The hydraulic power of the pump station is provided by its motor pump and hand pump in accordance with different hydraulic tests. It is proved in practice that the pump station is more adequate than normal hydraulic power source to tests which need the hydraulic pressure to be hold for a long time, such as a leak test.

  17. Related research with thermo hydraulics safety by means of Trace code; Investigaciones relacionadas con seguridad termohidraulica con el codigo TRACE

    Energy Technology Data Exchange (ETDEWEB)

    Chaparro V, F. J.; Del Valle G, E. [IPN, Escuela Superior de Fisica y Matematicas, UP - Adolfo Lopez Mateos, Edif. 9, 07738 Mexico D. F. (Mexico); Rodriguez H, A.; Gomez T, A. M. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Sanchez E, V. H.; Jager, W., E-mail: evalle@esfm.ipn.mx [Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz I, D-76344 Eggenstein - Leopoldshafen (Germany)

    2014-10-15

    In this article the results of the design of a pressure vessel of a BWR/5 similar to the type of Laguna Verde NPP are presented, using the Trace code. A thermo hydraulics Vessel component capable of simulating the behavior of fluids and heat transfer that occurs within the reactor vessel was created. The Vessel component consists of a three-dimensional cylinder divided into 19 axial sections, 4 azimuthal sections and two concentric radial rings. The inner ring is used to contain the core and the central part of the reactor, while the outer ring is used as a down comer. Axial an azimuthal divisions were made with the intention that the dimensions of the internal components, heights and orientation of the external connections match the reference values of a reactor BWR/5 type. In the model internal components as, fuel assemblies, steam separators, jet pumps, guide tubes, etc. are included and main external connections as, steam lines, feed-water or penetrations of the recirculation system. The model presents significant simplifications because the object is to keep symmetry between each azimuthal section of the vessel. In most internal components lack a detailed description of the geometry and initial values of temperature, pressure, fluid velocity, etc. given that it only considered the most representative data, however with these simulations are obtained acceptable results in important parameters such as the total flow through the core, the pressure in the vessel, percentage of vacuums fraction, pressure drop in the core and the steam separators. (Author)

  18. Comparison Of The Powers Of Energy Losses In A Variable Capacity Displacement Pump Determined Without Or With Taking Into Account The Power Of Hydraulic Oil Compression

    Directory of Open Access Journals (Sweden)

    Paszota Zygmunt

    2015-04-01

    Full Text Available Powers of energy losses in a variable capacity displacement pump are compared with or without taking into account the power of hydraulic oil compression. Evaluation of power of liquid compression in the pump was made possible by the use of method, proposed by the Author, of determining the degree of liquid aeration in the pump. In the method of determining the liquid aeration in the pump and of powers of volumetric losses of liquid compression a simplified formula (qPvc × ΔpPi/2 was used describing the field of indicated work of volumetric losses qPvc of liquid compression during one shaft revolution at indicated increase ΔpPi of pressure in the chambers. Three methods were used for comparing the sum of powers of volumetric losses ΔPPvl due to leakage and ΔPPvc of compression and also ΔPPm|ΔpPi of mechanical losses resulting from increase ΔpPi of indicated pressure in the working chambers.

  19. Pump characteristics and applications

    CERN Document Server

    Volk, Michael

    2013-01-01

    Providing a wealth of information on pumps and pump systems, Pump Characteristics and Applications, Third Edition details how pump equipment is selected, sized, operated, maintained, and repaired. The book identifies the key components of pumps and pump accessories, introduces the basics of pump and system hydraulics as well as more advanced hydraulic topics, and details various pump types, as well as special materials on seals, motors, variable frequency drives, and other pump-related subjects. It uses example problems throughout the text, reinforcing the practical application of the formulae

  20. Hydraulic System Design of Hydraulic Actuators for Large Butterfly Valves

    OpenAIRE

    HUANG, Ye; Liu, Changsheng; Shiongur Bamed

    2014-01-01

    Hydraulic control systems of butterfly valves are presently valve-controlled and pump-controlled. Valve-controlled hydraulic systems have serious power loss and generate much heat during throttling. Pump-controlled hydraulic systems have no overflow or throttling losses but are limited in the speed adjustment of the variable-displacement pump, generate much noise, pollute the environment, and have motor power that does not match load requirements, resulting in low efficiency under...

  1. 挖掘机正流量泵控液压系统的特性分析%Analysis on positive flow pump control system of hydraulic excavator

    Institute of Scientific and Technical Information of China (English)

    贾文华; 殷晨波; 曹东辉; 陈克雷

    2011-01-01

    采用泵控挖掘机液压系统特性分析方法,在分析泵的输出特性的基础上,给出确定先导压力信号和控制泵排量的方法,并对泵的输出特性进行了仿真和实验研究.结果表明:正流量控制下,泵的排量由执行器流量需求和油泵的p-Q曲线动态实时调节,系统具有良好的负载流量适应性和负载敏感性,其液压系统中不存在负压,只有约0.5 MPa的背压,回油功率损失几乎为0.%Some problems were studied for the positive flow control of pump system of hydraulic excavator. Based on the analysis of pump output characteristics, the control method for pilot pressure and the pump displacement was given. The pump output characteristics were investigated by simulation and experiment. Results showed that flow was adjusted by flow required by actuator and the p - Q curve of main pump. For the positive system, the excavator had good load flow adaptability and load sensitivity. The power loss of returning oil path was almost zero. In the returning path, the negative pressure was only 0.5 Mpa for the positive system.

  2. Evaluation of advanced hydraulic turbomachinery for underground pumped hydroelectric storage. Part 2. Two-stage regulated pump/turbines for operating heads of 1000 to 1500 m

    Energy Technology Data Exchange (ETDEWEB)

    Blomquist, C.A.; Frigo, A.A.; Degnan, J.R.

    1979-10-01

    This UPHS report applies to Francis-type, reversible pump/turbines regulated with gating systems. The first report, however, covered single-stage regulations; this report covers two-stage regulations. Development of a two-stage regulated pump/turbine appears to be attractive because the proposed single-drop UPHS concept requires turbomachinery with a head range of 1000 to 2000 m. With turbomachinery of this range available, the single-drop scheme offers a simple and economic UPHS option. Six different two-stage, top-gated pump/turbines have been analyzed: three that generate 500 MW and three that generate 350 MW. In each capacity, one machine has an operating head of 1000 m, another has a head of 1250 m, and the third has a head of 1500 m. The rated efficiencies of the machines vary from about 90% (1000-m head) to about 88% (1500-m head). Costs in 1978 $/kW for the three 500-MW units are: 20.5 (1000 m), 16.5 (1250 m), and 13.5 (1500 m). Corresponding costs for the three 350-MW units are 23, 18, and 14 $/kW. No major turbomachinery obstacles are foreseen that could hamper development of these pump/turbines. Further model testing and development are needed before building them.

  3. Características construtivas de um carneiro hidraúlico com materiais alternativos Hydraulic ram pump manufacturer features using alternative materials

    Directory of Open Access Journals (Sweden)

    Denis C. Cararo

    2007-08-01

    Full Text Available O objetivo deste trabalho foi avaliar um carneiro hidráulico construído com conexões roscáveis de PVC roscáveis e metálicas e garrafa de polietileno tereftálico (PET. O estudo foi realizado no Laboratório de Hidráulica da Universidade Federal de Lavras, MG. Testaram-se tamanhos de câmaras de ar (0,6 e 2,5L, diâmetros de furos da tampa da garrafa (5, 15 e 25mm, tipos de garrafa plástica (descartável de guaraná e descartável e retornável de refrigerante de cola, e posições da válvula de escape (vertical e horizontal, a diferentes pressões de recalque (48,39 a 483,92kPa, a cada 48,39 kPa. O desnível do reservatório de alimentação ao carneiro hidráulico foi mantido constante a 4,36m. Os resultados indicaram que a combinação de características construtivas que possibilitam melhor rendimento, maior vazão recalcada, menor vazão de alimentação e menor desperdício, foi o uso de garrafa PET descartável ou retornável com capacidade de 0,6L, válvula de escape na horizontal e tamanho de furo de 25mm na tampa da garrafa.Tests were conducted at the Hydraulics Laboratory of Universidade Federal de Lavras - UFLA, Lavras, to evaluate a hydraulic ram pump built with PVC and metallic threadable connections, and a bottle made with polyethylene tereftalic, known as PET. The manufacturer features tested were: bottle size (0.6 and 2.5L, hole size of the bottle top (5, 15 and 25mm, bottle models (disposable and returnable and valve positions (horizontal and vertical. The operational hydraulic head was 4.36m and the simulated pump elevation pressures were 48.39 to 483.92kPa and 48.39 to 48.39kPa. The best efficiency, the highest pumped water flow, the lowest operational water flow and the lowest waste water flow were obtained using the 0.6L PET disposable or returnable bottle with horizontal valve position and top size of 25mm.

  4. Means-End based Functional Modeling for Intelligent Control: Modeling and Experiments with an Industrial Heat Pump System

    DEFF Research Database (Denmark)

    Saleem, Arshad

    2007-01-01

    The purpose of this paper is to present a Multilevel Flow Model (MFM) of an industrial heat pump system and its use for diagnostic reasoning. MFM is functional modeling language supporting an explicit means-ends intelligent control strategy for large industrial process plants. The model is used...

  5. Means-End based Functional Modeling for Intelligent Control: Modeling and Experiments with an Industrial Heat Pump System

    DEFF Research Database (Denmark)

    Saleem, Arshad

    2007-01-01

    The purpose of this paper is to present a Multilevel Flow Model (MFM) of an industrial heat pump system and its use for diagnostic reasoning. MFM is functional modeling language supporting an explicit means-ends intelligent control strategy for large industrial process plants. The model is used...

  6. Improvement of photovoltaic pumping systems based on standard frequency converters by means of programmable logic controllers

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Ramos, Jose [Departamento de Electronica, Universidad de Malaga, Complejo Tecnologico de Teatinos (2.2.39), 29071 Malaga (Spain); Narvarte-Fernandez, Luis; Poza-Saura, Fernando [Instituto de Energia Solar, Universidad Politecnica de Madrid (IES-UPM), Avenida Complutense s/n (204), 28040 Madrid (Spain)

    2010-01-15

    Photovoltaic pumping systems (PVPS) based on standard frequency converters (SFCs) are currently experiencing a growing interest in pumping programmes implemented in remote areas because of their high performance in terms of component reliability, low cost, high power range and good availability of components virtually anywhere in the world. However, in practical applications there have appeared a number of problems related to the adaptation of the SFCs to the requirements of the photovoltaic pumping systems (PVPS). Another disadvantage of dedicated PVPS is the difficulty in implementing maximum power point tracking (MPPT). This paper shows that these problems can be solved through the addition of a basic industrial programmable logic controller (PLC) to the system. This PLC does not increase the cost and complexity of the system, but improves the adaptation of the SFC to the photovoltaic pumping system, and increases the overall performance of the system. (author)

  7. Insulin pump (dose-to-dose) accuracy: what does it mean and when is it important?

    Science.gov (United States)

    Zisser, Howard

    2014-11-01

    This article reviews the concept of using the proper methods for the proper task, in this case measuring dose-to-dose accuracy of continuous subcutaneous insulin infusion pumps. © 2014 Diabetes Technology Society.

  8. Improvement of a polarized alkali ion source by means of optical pumping

    Energy Technology Data Exchange (ETDEWEB)

    Dreves, W.; Koch, E.; Jaensch, H.; Kamke, W.; Broermann, W.; Fick, D.

    1982-01-01

    A source for polarized alkali ions can be improved considerably by optical pumping of the atom beam in combination with a modified weak field transition. M-level populations were investigated using laser induced fluorescence in a magnetic field.

  9. Basic hydraulics

    CERN Document Server

    Smith, P D

    1982-01-01

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

  10. Efficiency by means of intelligence. Control engineering increases the performance of pumping and shredders; Effizienz durch Intelligenz. Steuerungstechnik steigert die Leistung von Pump- und Zerkleinerungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Wenner, Carsten; Vogelsang, Hugo [Maschinenbau GmbH, Essen (Germany)

    2009-01-15

    For a long time, modern machine tools are no more applicable efficiently without electronics. However, it is expected frequently from macerators and displacement pumps that they work completely without appropriate control engineering and/or with minimal control engineering. The achievement and efficiency of these systems can be improved by the investment into modern and intelligent control engineering clearly. Under this aspect, the author of the contribution under consideration reports on the application of the macerator RotaCut 5000 in the biogas plant Duderstadt. The protection from foreign bodies and for simultaneous substrate preparation, a RotaCut 5000 is connected before the rotary pump. For both devices, an appropriate performance control unit was installed. Rotary pump and RotaCut 5000 work reliably, efficiently and attain a power demand of 10 kW. This means a saving of 1,600 kW/h per week and a saving between 10,000 and 12,000 euros per year. The entire investment amortized after some months.

  11. 径向柱塞式变量液压泵的结构及工作原理%Structure and Operating Principle of Radial Piston Variable Hydraulic Pump

    Institute of Scientific and Technical Information of China (English)

    王霜; 王明章

    2014-01-01

    采用径向柱塞式变量液压泵作为主泵的闭心恒压式液压系统,其最大优点是能根据实际作业需要自动改变流量输出。就径向柱塞式变量液压泵的基本结构和工作原理进行了详细分析,以供实际使用中参考。%Using radial piston variable hydraulic pump as closed center constant hydraulic system of the main pump,its biggest advantage was based on the actual needs of the job,it could automatically change the flow output. The radial piston pump variable basic structure and operating principle was conducted,so as to provide the reference for actual use.

  12. A study of the key problem of optimum hydraulic design for a pump system with low head%低扬程泵装置优化水力设计的关键问题

    Institute of Scientific and Technical Information of China (English)

    徐磊; 陆林广; 梁金栋; 王刚; 董雷

    2012-01-01

    An in-depth study on the problem of optimum hydraulic design for a pump system with low head has been made in this paper. The efficiency of a pump system with low head is divided into two aspects: one is pump efficiency and the other is conduit efficiency. Some problems about the definition of pump segment in the pump system, efficiency modification for the pump segment and flow pattern of inlet conduit in the pump system are discussed. The influence of conduit hydraulic loss on the conduit efficiency and pump system efficiency is analyzed and the influence of both flow velocity and flow pattern on the conduit hydraulic loss is illustrated by calculation samples, from which the conclusions are drawn as follows: under the condition of low head, the key problem of how to increase the pump system efficiency is to reduce the conduit hydraulic loss as much as possible; The essential way to reduce the conduit hydraulic loss may be to lower the flow velocity and improve the flow pattern in the conduit. The approaches to reduce the conduit hydraulic loss mainly include: to choose the type of pump system and conduit with the optimal hydraulic performance, to suitably lower pump nD value, to choose better pump model, to suitably relax the restrictions for conduit control size, and to sufficiently optimize hydraulic design for conduit shape.%对低扬程泵装置的优化水力设计问题进行了较为深入的研究.将低扬程泵装置效率分解为水泵效率和流道效率两个方面,讨论了泵装置中泵段的概念和泵段效率的修正等问题,分析了流道水力损失对流道效率及泵装置效率的影响,通过实例说明了流道内的流速和流态对流道水力损失的影响,得到以下结论:在低扬程条件下,尽可能减小流道水力损失是提高泵装置效率的关键;减小流道水力损失的关键是降低流道内的流速和改善流道内的流态,其途径主要包括选择水力性能最优的泵装置型式和流道

  13. 基于AMESim的某混凝土泵液压回油管路分析%Analysis of Hydraulic Oil Return Pipeline of One Concrete Pump Based on AMESim

    Institute of Scientific and Technical Information of China (English)

    杨鑫

    2011-01-01

    介绍了某混凝土泵液压系统回油管路的设计,分析了减小该液压系统振荡、保护关键液压元件的方法.采用AMESim软件对该液压系统进行建模与仿真,得出了该回油路优化设计的参数.%The design of hydraulic oil return pipeline of one concrete pump was introduced.How to decrease the vibration of hydraulic system and defend the key hydraulic components of the system were analyzed.Modeling and simulation of the hydraulic system were done on AMEsim, and the optimized parameters were gained.

  14. EQUILIBRIO HIDRÁULICO EN SISTEMAS DE BOMBEO MINERO: ESTUDIO DE CASO HYDRAULIC BALANCE ON MINE PUMPING SYSTEMS: A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Luis Enrique Ortiz Vidal

    2010-12-01

    Full Text Available Fue evaluada la influencia del uso de los métodos de Hazen-Williams y Darcy-Weisbach en el establecimiento del equilibrio hidráulico para un sistema de bombeo minero. Empresas mineras con actividad subterránea hacen uso de estaciones de bombeo para evacuar el agua, producto de la profundización de sus labores. Proyectistas y vendedores de equipos de bombeo usan diferentes expresiones para la estimación de la pérdida de carga total del sistema, parámetro importante para la determinación del equilibrio hidráulico. El presente estudio tiene como objetivo analizar y validar la aplicación de algunas de estas expresiones para un sistema de bombeo minero. Las principales características del estudio de caso son: caudal de agua de 1.350 l/s; tuberías de acero y HDPE de 16 in y 18 in de diámetro, respectivamente; longitud total de la tubería de 2.900 m; y una altura geodésica de 230 m. Los cálculos fueron realizados con los métodos ya mencionados teniendo las expresiones de Haaland, Swamee-Jain y Churchill como factores de fricción. Los resultados obtenidos fueron comparados con los medidos en campo, teniéndose una desviación máxima del sistema de 28,6% y 3,1% para la pérdida de carga y Hman total, respectivamente.This study evaluates the influence of the Hazen-Williams and Darcy-Weisbach methods on the hydraulic balance of a mine pumping system. Underground mining sompanies use pumping stations for evacuate the produced water. Designers and equipment sellers use different expressions to estimate the head loss. This study analyzes and validates the implementation of some of these expressions to a mine pumping system. The features of the case study are: water flow rate of 1350 l/s, steel and HDPE diameter pipes of 16in. and 18in., respectively. The total pipe length is 2900m, and the hydraulic height difference is 230 m. The calculations were performed by the above-mention methods, taking the expressions of Haaland, Swamee-Jain and

  15. 工程机械液压系统性能试验台中的液压泵动态性能试验研究%Experimental Study on Dynamic Performance of Hydraulic Pump of Construction Machinery Hydraulic System Performance Testing Platform

    Institute of Scientific and Technical Information of China (English)

    朱发新; 林少芬; 龚雅萍; 王伟军; 张志斌

    2011-01-01

    Taking the steering system of the construction machinery hydraulic system performance testing platform as physical model, the dynamic performances of the hydraulic pump were studied by local experiments. According to the test results, the influences of motor speed, fuel tank position, load voltage on the hydraulic pump performance as well as the effect of hydraulic pump pressure and flow change to the hydraulic system were obtained.%以工程机械液压系统性能试验台的转向系统为物理模型,通过试验研究液压泵的动态性能.根据试验结果,得出油箱位置、变频电机转速、加载电压等系统工况对液压泵动态性能的影响,同时得出液压泵压力、流量的动态变化对液压系统的影响.

  16. Trend of hydraulic units

    Energy Technology Data Exchange (ETDEWEB)

    Deshimaru, Jun' ichi

    1988-11-01

    The gear, vane and piston pumps occupy a more then 90% share in the hydraulic pumps. Comparatively large pumps are mainly variable delivery piston pumps. The piston pumps are comparatively high in output density (output per unit weight), indicating the hydraulic pump in performance, and tend to become higher and higher in it. Though they are mainly 210 to 350kgf/cm/sup 2/ in rated pressure, some of them come to surpass 400kgf/cm/sup 3/ in it. While the progress in computation also requires the high speed operation, high accuracy and other severe conditions for the hydraulic units, which accordingly and increasingly intensify the requirement for hydraulic oil in abrasion resistibility, oxidation stability and response characteristics. While cavitation comes to easily occur, which considerably and disadvantageously influences hydraulic oil in life through degradation, noise level and respondingness. From now on, the development of high performance oil and study of mechanical structure are important. 19 references, 9 figures, 2 tables.

  17. Custo de bombas centrífugas funcionando como turbinas em microcentrais hidrelétricas Cost of pumps as hydraulic turbines for micro-scale hydropower

    Directory of Open Access Journals (Sweden)

    Carlos R. Balarim

    2004-04-01

    places where they should be implanted. Pumps As Turbines (PAT have been studied. These equipment costs were obtained by consulting directly the manufacturers, and also the Ponta Grossa - PR city, Brazil, market. The results have shown that, concerning the micro hydroelectric power plants, whenever the costs constitute the major aspect and always considering units until 50 kW power, the option to PAT must be considered instead of hydraulic turbines.

  18. Use of time-subsidence data during pumping to characterize specific storage and hydraulic conductivity of semi-confining units

    Science.gov (United States)

    Burbey, T. J.

    2003-09-01

    A new graphical technique is developed that takes advantage of time-subsidence data collected from either traditional extensometer installations or from newer technologies such as fixed-station global positioning systems or interferometric synthetic aperture radar imagery, to accurately estimate storage properties of the aquifer and vertical hydraulic conductivity of semi-confining units. Semi-log plots of time-compaction data are highly diagnostic with the straight-line portion of the plot reflecting the specific storage of the semi-confining unit. Calculation of compaction during one-log cycle of time from these plots can be used in a simple analytical expression based on the Cooper-Jacob technique to accurately calculate specific storage of the semi-confining units. In addition, these semi-log plots can be used to identify when the pressure transient has migrated through the confining layer into the unpumped aquifer, precluding the need for additional piezometers within the unpumped aquifer or within the semi-confining units as is necessary in the Neuman and Witherspoon method. Numerical simulations are used to evaluate the accuracy of the new technique. The technique was applied to time-drawdown and time-compaction data collected near Franklin Virginia, within the Potomac aquifers of the Coastal Plain, and shows that the method can be easily applied to estimate the inelastic skeletal specific storage of this aquifer system.

  19. Analysis and Reform on Reliability of Circulating Water Pump and Hydraulic-control Butterfly Valve Control System%循环水泵及液控蝶阀控制系统可靠性分析及改造

    Institute of Scientific and Technical Information of China (English)

    郭凌云

    2014-01-01

    This paper introduces and analyzes existing problems of circulating water pump and hydraulic-control butterfly valve control system in Guangdong Datang Chaozhu power plant and proposes optimization measures for improving reliabili-ty.Referred measures are feasible to greatly improve reliability of circulating water pump and hydraulic-control butterfly valve control system and safety of the unit.%对广东大唐潮州电厂循环水泵、液控蝶阀控制系统存在的问题进行了介绍和分析,并提出提高可靠性改造的优化措施。这些措施大大提高了循环水泵及液控蝶阀控制系统的可靠性及机组的安全性。

  20. Pumping life

    DEFF Research Database (Denmark)

    Sitsel, Oleg; Dach, Ingrid; Hoffmann, Robert Daniel

    2012-01-01

    of membrane proteins: P-type ATPase pumps. This article takes the reader on a tour from Aarhus to Copenhagen, from bacteria to plants and humans, and from ions over protein structures to diseases caused by malfunctioning pump proteins. The magazine Nature once titled work published from PUMPKIN ‘Pumping ions......’. Here we illustrate that the pumping of ions means nothing less than the pumping of life....

  1. Hydraulic System Design of Hydraulic Actuators for Large Butterfly Valves

    Directory of Open Access Journals (Sweden)

    Ye HUANG

    2014-09-01

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

  2. Nuclear spin polarized H and D by means of spin-exchange optical pumping

    Science.gov (United States)

    Stenger, Jörn; Grosshauser, Carsten; Kilian, Wolfgang; Nagengast, Wolfgang; Ranzenberger, Bernd; Rith, Klaus; Schmidt, Frank

    1998-01-01

    Optically pumped spin-exchange sources for polarized hydrogen and deuterium atoms have been demonstrated to yield high atomic flow and high electron spin polarization. For maximum nuclear polarization the source has to be operated in spin temperature equilibrium, which has already been demonstrated for hydrogen. In spin temperature equilibrium the nuclear spin polarization PI equals the electron spin polarization PS for hydrogen and is even larger than PS for deuterium. We discuss the general properties of spin temperature equilibrium for a sample of deuterium atoms. One result are the equations PI=4PS/(3+PS2) and Pzz=PSṡPI, where Pzz is the nuclear tensor polarization. Furthermore we demonstrate that the deuterium atoms from our source are in spin temperature equilibrium within the experimental accuracy.

  3. Hydraulic wind energy conversion system

    Energy Technology Data Exchange (ETDEWEB)

    1981-07-01

    The purpose of this research was to design, build and test a hydraulic wind energy system. This design used a three bladed turbine, which drove a hydraulic pump. The energy is transmitted from the pump through a long hose and into a hydraulic motor, where the energy is used. This wind system was built and tested during the winter of 1980-1981. The power train included a five meter, three bladed wind turbine, a 9.8:1 ratio gearbox, a 1.44 cubic inch displacement pump with a small supercharge gear pump attached. The hydraulic fluid was pumped through a 70', 3/4'' I-D-high pressure flexhose, then through a volume control valve and into a 1.44 cubic inch displacement motor. The fluid was returned through a 70', 1'' I-D-flexhose.

  4. Effect of Pumping Chamber Outlet Contraction Angle on Hydraulic Performance of Main Nuclear Reactor Pump%反应堆主泵压水室出口收缩角对水力性能的影响

    Institute of Scientific and Technical Information of China (English)

    朱荣生; 李小龙; 袁寿其; 付强; 王秀礼

    2012-01-01

    An RCP (reactor coolant pump) impeller and diffuser are designed to meet the hydraulic performance needs of the nuclear reactor coolant pump in a domestic 1000MW nuclear power plant. In order to study the effect of the pumping chamber outlet contraction angle a, 13 kinds of a are designed and Pro/E is utilized for three-dimensional design, and CFD code Fluent is utilized for numerical simulation. Finally, the internal velocity vector and streamline of the RCP are obtained. It is revealed that the contraction angle a has a significant effect on the connection area between pumping chamber and outlet. As a is between 12° and 16°, and the efficiency of the RCP is above 70%. When a is 15°, the efficiency reaches to the maximum 74.2%. When?is 15° and other parameters unchanged, the reverse flow region of the impeller inlet and diffuser outlet becomes larger with the decrease of the flow rates. When the flow increases, the reverse region approaches closer to the impeller inlet. Reverse flow is the main cause of the pressure fluctuation of the connection area between pumping chamber and outlet, and the farther away the design point, the more serious the pressure fluctuation.%针对国内某百万千瓦核反应堆主泵的水力性能要求,完成主泵叶轮和导叶的设计;为研究出口收缩角α对水力性能的影响,设计了13种压水室出口收缩角,采用三维软件Pro/E完成了三维造型;利用计算流体力学( CFD)软件Fluent进行定常与非定常三维数值模拟,得到内部流场特性及计算点的压力脉动情况,并对其进行分析.结果表明:收缩角α对压水室与出口交接处的前后区域影响显著,收缩角α在12°~16°范围内,主泵效率均在70%以上,α=15°时效率达最大值74.2%;在α=15°且其他结构参数不变的情况下,随着流量的降低,主泵叶轮进口前和导叶出口处回流区域逐渐扩大;随着流量的增加,叶轮进口前回流区域逐渐向叶轮进口偏移

  5. Design&Manufacturing of Hydraulic Pump Test-bed with Power Recovery%功率回收型液压泵试验台的设计与制造

    Institute of Scientific and Technical Information of China (English)

    王文凯; 宫景瑞; 刘玉峰; 马忠

    2015-01-01

    一般来说,液压泵出厂试验、型式试验及寿命试验使用的试验设备,其驱动功率是由被试泵所能产生和达到的功率所决定的.在进行试验项目测试时,泵所产生的压力能不是来做功,而是要经过节流或溢流加载的方式转换成热能或其他形式来把它消耗掉.在液压试验台的设计和制造中,能否对这部分能量进行回收和利用,而不是任其被动消耗,这是该文要讨论和解决的问题.%As a rule, The test equipment which be used in hydraulic pump's factory test, type test and life test, It's driving power is deter-mined by the peak energy of tested Pump. In test run, the pump's pressure energy is not for working, but for transforming into heat energy or other forms by throttling or overflow loading. There is a problem in design and fabrication of hydraulic pump test-bedthat is whether this part of the energy can be reclaimed and reused rather than consumed passively. This paper will discuss and solve this problem.

  6. Reducing leaks in water distribution networks. Controlling pressure by means of automatic hydraulic valves; Reduccion de fugas en redes de distribucion de agua. Control de la presion mediante valvulas hidraulicas automaticas

    Energy Technology Data Exchange (ETDEWEB)

    Singla Font, S.

    2005-07-01

    Any water distribution network, bet it of drinking water or irrigation water, always loses an inevitable amount. One of the main ways to reduce leaks is to optimise the pressure in the network by means of hydraulic valves with different types of control devices. These can be either completely hydraulic or supplemented by electronic systems. (Author)

  7. METHOD FOR OPTIMIZING THE ENERGY OF PUMPS

    NARCIS (Netherlands)

    Skovmose Kallesøe, Carsten; De Persis, Claudio

    2013-01-01

    The device for energy-optimization on operation of several centrifugal pumps controlled in rotational speed, in a hydraulic installation, begins firstly with determining which pumps as pilot pumps are assigned directly to a consumer and which pumps are hydraulically connected in series upstream of t

  8. 船舶综合液压推进及其泵马达设计%Integrated Hydraulic Propulsion Ship and Its Pump and Motor Design

    Institute of Scientific and Technical Information of China (English)

    孙玉清; 纪玉龙; 陈海泉

    2007-01-01

    为解决船舶在向大型化、高速化方向发展时船舶主机设计困难,机舱布置不合理以及机动性能差等问题,提出了一种新型船舶推进方式,即船舶综合液压推进.给出了该推进方式的推进原理,通过工况配合特性曲线图,对其工况配合特性进行分析,对该推进方式的优缺点进行讨论并对其重要组件液压泵以及马达进行设计计算.结果表明船舶综合液压推进具有其独特的优点,是对现有船舶推进方式的有益补充.%Conventional ship propulsion methods meet some limitations in ship development towards high-speed,large-scale and high-power.A new ship propulsion method,integrated hydraulic propulsion (IHP),was put forward to solve the problem.Then further research work was done on the principle of IHP method.Working condition-matching characteristic was discussed through the working condition matching characteristic chart.After that,the advantages and disadvantages of IHP method were given.And the pump and motor,important parts of IHP,was designed through physical analytical method.IHP method can be used extensively in some special kinds of ship for its own characteristics.To a certain extent,the limitation problem of ship propulsion method can be solved.IHP method diversifies the existing ship propulsion methods.

  9. A method of applying two-pump system in automatic transmissions for energy conservation

    Directory of Open Access Journals (Sweden)

    Peng Dong

    2015-06-01

    Full Text Available In order to improve the hydraulic efficiency, modern automatic transmissions tend to apply electric oil pump in their hydraulic system. The electric oil pump can support the mechanical oil pump for cooling, lubrication, and maintaining the line pressure at low engine speeds. In addition, the start–stop function can be realized by means of the electric oil pump; thus, the fuel consumption can be further reduced. This article proposes a method of applying two-pump system (one electric oil pump and one mechanical oil pump in automatic transmissions based on the forward driving simulation. A mathematical model for calculating the transmission power loss is developed. The power loss transfers to heat which requires oil flow for cooling and lubrication. A leakage model is developed to calculate the leakage of the hydraulic system. In order to satisfy the flow requirement, a flow-based control strategy for the electric oil pump is developed. Simulation results of different driving cycles show that there is a best combination of the size of electric oil pump and the size of mechanical oil pump with respect to the optimal energy conservation. Besides, the two-pump system can also satisfy the requirement of the start–stop function. This research is extremely valuable for the forward design of a two-pump system in automatic transmissions with respect to energy conservation and start–stop function.

  10. Design and Analysis of Hydraulic Chassis with Obstacle Avoidance Function

    Science.gov (United States)

    Hong, Yingjie; Zhang, Xiang

    2017-07-01

    This article mainly expounds the design of hydraulic system for the hydraulic chassis with obstacle avoidance function. Including the selection of hydraulic motor wheels, hydraulic pump, digital hydraulic cylinder and the matching of engine power. And briefly introduces the principle of obstacle avoidance.

  11. Determination of the hydraulic characteristics by means of integral parameters in a model of wetland with subsuperficial flow

    Energy Technology Data Exchange (ETDEWEB)

    Vallejos, G.; Ponce Caballero, C.; Quintal Franco, C.; Mendez Novelo, R.

    2009-07-01

    The main objective of this study was to assess the portions of plug flow and death zones using tracer tests by empiric models as Wolf-Resnick and Dispersion in evaluate bed-packed reactors with horizontal subsurface flow, as a model of a constructed wetland. In order to assess the hydraulic behavior of systems such as packed-bed reactors and constructed wetlands both of subsurface flow, it is necessary to study and evaluate them modifying some variables while others remain constant. As well it is important to use mathematical models to describe, as precise as possible, the different phenomenon inside the systems, in such a way that these models bring information in an integral way to predict the behavior of the systems. (Author)

  12. Systematic Method for Evaluating Extraction and Injection Flow Rates for 100-KR-4 and 100-HR-3 Groundwater Operable Unit Pump-and-Treat Interim Actions for Hydraulic Containment

    Energy Technology Data Exchange (ETDEWEB)

    Spiliotopoulos, Alexandros A.

    2013-03-20

    This document describes a systematic method to develop flow rate recommendations for Pump-and-Treat (P&T) extraction and injection wells in 100-KR-4 and 100-HR-3 Groundwater Operable Units (OU) of the Hanford Site. Flow rate recommendations are developed as part of ongoing performance monitoring and remedy optimization of the P&T interim actions to develop hydraulic contairnnent of the dissolved chromium plume in groundwater and protect the Columbia River from further discharges of groundwater from inland. This document details the methodology and data required to infer the influence of individual wells near the shoreline on hydraulic containment and river protection and develop flow rate recommendations to improve system performance and mitigate potential shortcomings of the system configuration in place.

  13. Hydraulic rams; a comparative investigation

    NARCIS (Netherlands)

    Tacke, J.H.P.M.

    1988-01-01

    A mathematical model describing the essential features of hydraulic ram operation is developed in order to clarify the possibilities and limitations of the ram relative to its site and its adjustments. The model distinguishes three different periods in the pumping cycle of the hydraulic ram: acceler

  14. A Distributed Algorithm for Energy Optimization in Hydraulic Networks

    DEFF Research Database (Denmark)

    Kallesøe, Carsten; Wisniewski, Rafal; Jensen, Tom Nørgaard

    2014-01-01

    is distributed in the sense that all calculations are implemented where the necessary information is available, including both parameters and measurements. A communication network between the pumps is implemented for global optimization. The local implementation of the algorithm means that the system becomes......An industrial case study in the form of a large-scale hydraulic network underlying a district heating system is considered. A distributed control is developed that minimizes the aggregated electrical energy consumption of the pumps in the network without violating the control demands. The algorithm...... a Plug & Play control system as most commissioning can be done during the manufacture of the pumps. Only information on the graph-structure of the hydraulic network is needed during installation....

  15. The Influence of Rotational Inertia on the Hydraulic Transition Process of Yellow Pumping Stations in Ji-xian County%转动惯量对吉县提黄泵站水力过渡过程的影响

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Rotational inertia of pumping units is not only the essential parameter to describe the running state of pump ,but also the significant parameter on an analysis of hydraulic transient ,research on safety protection and optimal design ,which has a great influ‐ence on the pump-stopping water hammer calculation .This paper has studied the First Pump Station of Ji-xian County's eastern yellow irrigation project ,made use of water hammer computing software to simulate hydraulic transient of pumps at sudden power failure ,and analyzed the connection between different rotational inertia and hydraulic transient under two-stage slow-closing butterfly valve and no valve conditions .The results show that increasing rotational inertia of pumping unit under no valve and two-stage slow-closing butterfly valve conditions ,can reduce water hammer pressure and decrease the reverse rotate speed of pumps ,and as rota‐tion inertia is growing ,decompression effect and pump reverse rotate speed reduction are weakened .Under two-stage slow-closing butterfly valve conditions ,water hammer pressure is increasing to a certain degree ,which may have a bad effect on decreasing the water hammer pressure made by increasing rotational inertia of the pump .Adjusting rotational inertia of the pump in water hammer protection is economical and effective ,which will promote the development of water hammer protection measures .%转动惯量不仅是描述水泵机组运行状况的重要参数,也是进行输水系统水力过渡过程分析、安全防护研究和优化设计的重要技术参数,对停泵水锤计算具有很大影响。论文以吉县东城提黄灌溉工程一级泵站为研究对象,利用水锤计算软件对其突然停泵过程进行模拟计算,分析无阀和两阶段缓闭蝶阀作用下不同转动惯量对其水力过渡过程的影响。模拟结果证实无阀和两阶段缓闭蝶阀作用时增大机组转动惯量可以有效减少水锤升压和降低水

  16. 液压隔膜泵用环状U型隔膜挠曲变形分析%Deflection analysis of annular U-diaphragm in hydraulic diaphragm pump

    Institute of Scientific and Technical Information of China (English)

    邓鸿英; 张生昌; 郑英臣

    2012-01-01

    To establish a basic theory system and design method for a new type of annular U-diaphragm in hydraulic diaphragm pumps, the relation between U-diaphragm deflection and deformation quantity was analyzed by using the nonlinear analysis function in finite element software Ansys. A thin, hollow, double shell U-diaphragm finite element model with geometry and material nonlinear character was established for the annular U-diaphragm used in the prototype of hydraulic diaphragm pump. The deflection of the U-diaphragm model was analyzed under different compression and stretch displacements when the displacements of the supported end were fixed, the displacements of the free supported end were prescribed and the pressure loads were applied on both sides of the U-diaphragm. The computed displacements of deflection were fitted by using differential evolution method where the correct fitting curves were determined by controlling mean square error and correlation coefficient and so on. The U-diaphragm movement was clarified and an empirical relation for the deflection was obtained, eventually a theoretical formula for camber working volume was given. All the results above will provide a theoretical basis for working mechanism and design optimization of an annular U-diaphragm.%为了建立新型液压隔膜泵用环状U型隔膜基础理论体系和设计方法,借助Ansys有限元分析软件的非线性分析工具,对其挠曲变形与变形量的关系进行了分析.以液压隔膜泵样机用环状U型隔膜为物理模型,建立了具有几何和材料双重非线性特性的环状U型隔膜的薄壁中空双层壳体有限元模型;在工作范围内,对模型固定支撑端施加固定约束,运动支撑端施加位移约束,内外表面施加面载荷,分析了模型在不同压缩、拉伸位移载荷下的挠曲变形;应用差分进化算法对环状U型隔膜挠曲变形的位移数据进行曲线拟合,通过控制均方差、相关系数和决定系数等判

  17. Hydraulic hoist-press

    Energy Technology Data Exchange (ETDEWEB)

    Babayev, Z.B.; Abashev, Z.V.

    1982-01-01

    The efficiency expert of the Angrenskiy production-technological administration of the production association Sredazugol A. V. Bubnov has suggested a hydraulic hoist-press for repairing road equipment which is a device consisting of lifting mechanism, press and test stand for verifying the high pressure hoses and pumps.

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

    CERN Document Server

    Parr, Andrew

    1991-01-01

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

  19. 泵控电液混合驱动系统在板料折弯机上的应用研发%The application and exploration of pump-control electro-hydraulic driving system in press brake for sheet metal

    Institute of Scientific and Technical Information of China (English)

    李振光; 汪立新; 温峰虎; 雷斌华; 茅问宇

    2013-01-01

    The electric and hydraulic principles of the pump-control electro-hydraulic driving system have been introduced in the text, as well as the advantages of pump-control press brake comparing with the conventional one. It is pointed out that the application of pump-control electro-hydraulic driving system is more widely, which has a broad marketing prospect.%介绍了泵控电液混合驱动系统的电气原理、液压原理,以及与传统折弯机相比泵控折弯机的诸多优点,指出泵控电液混合驱动系统的应用将越来越广泛,具有广阔的市场前景.

  20. 小舜江输水泵站液控蝶阀关阀时间及停泵方式改进%Hydraulic control butterfly valve closing vale time and pump stooping method improvement for the Xiaoshunjiang water transfer pump station

    Institute of Scientific and Technical Information of China (English)

    陈培兴

    2012-01-01

    大流量高扬程长距离输水工程供水泵站常采用二阶段液控调节蝶阀来最大限度降低关阀水锤.小角度关阀时间长,加之常规关阀停泵的方式,通常会引起机组、管路及阀门较大的振动.从泵站实际特点出发,尽量缩短关阀时间,改变常规关阀停泵方式,有效减小了振动和噪声.%The two-stage hydraulic control butterfly valve is usually used to reduce the closing valve water hammer in the high flow rate and long distance water supply pump station, which will usually cause long closing valve time with small angle and take the conventional closing valve method to stop the pump. This method will normally cause violent vibration on pumping unit, pipeline, and valve. Rased on practical characteristics (use the principles of water-pumping and energy-saving), in this paper the valve closing time was reduced as much as possible to change conventional pump stopping method, which was proved to be able to reduce the vibration and noise.

  1. Research on synchronous gear pump

    Institute of Scientific and Technical Information of China (English)

    LUAN Zhen-hui

    2010-01-01

    Based on a comprehensive analysis of the structure and existing problems of the gear pump, provided a structure principle of a synchronous gear pump. The discussions focused on the working principle, construction features and finite element analysis of the hydraulic gear. The research indicates that the new pump has such advantages as lower noise, better distributed flow and a high work pressure, and it can be widely used in hydraulic systems.

  2. Axial-flow pump hydraulic analysis and experiment under different swept-angles of guide vane%不同导叶叶片掠角下轴流泵段水力特性分析及试验

    Institute of Scientific and Technical Information of China (English)

    石丽建; 汤方平; 周捍珑; 涂恋恋; 谢荣盛

    2015-01-01

    Based on the computational fluid dynamics (CFD) software, this paper studied the influence of the post guide vane under different sweep angles on the hydraulic performance of the axial flow pump device. The purpose was that through changing the angle of blade forward and back sweeping, the post guide vane could as much as possibly recover the velocity circulation of the impeller outlet, at the same time, the hydraulic loss of the guide vane could be not too large, so as to improve the hydraulic characteristics of the axial flow pump device. This paper used the Turbo-Grid software to build the model and carry out the mesh division of the post guide vane and the impeller, used the Pro/E software to build the models of the inlet straight pipe with water-guiding cone and the standard 60°outlet pipe, and then used the ICEM to carry out the structured-grid division. Then, the hydraulic property of the axial flow pump device was analyzed through the CFX software. There were 6 different post guide vane sweeping schemes, which were forward sweep 24°, forward sweep 16°, forward sweep 8°, 0°, back sweep 8°and back sweep 16°. Numerical simulation of the axial flow pump device adopted the standardk-ε model, and each sweeping scheme of post guide vane had 8 flow points including 280, 300, 320, 340, 360, 380, 400 and 420 L/s. The influence of different post guide vane sweeping angles on the energy characteristics of the axial flow pump was analyzed under the design condition and the non-design condition. Then the hydraulic loss of the post guide vane and the outlet pipe was calculated and analyzed. Finally, the experimental study of the energy performance of the axial flow pump device was carried out. The results showed that, the test performance curve trend was consistent with the numerical simulation; the flow-head curve showed a little deviation under small flow, other parts fitted well, and the flow-efficiency curve did not fit so well, but the error between the test

  3. Analysis on Discharge Characteristics of the Variable Frequency Electric Motor Pump in Aircraft Hydraulic System%飞机液压系统变频电动泵输出特性分析

    Institute of Scientific and Technical Information of China (English)

    高锋; 夏鹤鸣

    2015-01-01

    Focusing on the discharge pressure and flow control problem of hydraulic pump powered by variable frequency electric power system in aircraft, the pressure control structure with the unload function was modeled and analyzed. Discharge characteristics of the pump under variable frequency were obtained and the feasibility of the variable frequency electric pump was validated.%针对某型飞机采用变频供电系统后液压系统电动泵在大频率范围内工作造成的压力流量控制问题,提出了包含卸荷功能的电动泵压力控制结构,建模并分析了该电动泵输出特性,得到典型供电频率下该电动泵的工作特性,验证了这种变频电动泵调压结构的可行性。

  4. Carneiro hidráulico com tubulação de alimentação em aço galvanizado e em PVC Hydraulic ram pump perfomance with PVC and steel pipes

    Directory of Open Access Journals (Sweden)

    Caroline Abate

    2002-03-01

    Full Text Available A recente crise da energia convencional tem ocasionado a exploração de fontes alternativas de energia. O bombeamento de água utilizando carneiro hidráulico é amplamente empregado em propriedades onde a energia elétrica é escassa ou inexistente. Procurando dar subsídios técnicos para a utilização do PVC nos sistemas de alimentação de um carneiro hidráulico, foi desenvolvido um experimento com objetivo de avaliar o desempenho de um carneiro hidráulico quando alimentado por uma tubulação de PVC e outra de aço galvanizado, sob três alturas de queda (2,1, 3,8 e 4,7 m. Foi utilizada a equação de D'Aubussion's para a avaliação do rendimento, calculado a partir de leituras de altura de recalque, vazão de escape, vazão de recalque e altura de alimentação. Pode-se conseguir o máximo rendimento com o carneiro hidráulico utilizando-se de tubulação de PVC com até 4,2 m de desnível; além desse valor a tubulação de aço galvanizado é mais eficiente.The recent conventional energy crisis is leading to the exploration of alternative energy sources. The pumping of water using ram pumps is widely used in farms where electric energy is scarce or inexistent. This experiment was carried out to evaluate the performance of an hydraulic ram pump utilizing two kinds of supply pipes (PVC and steel using three different supply heads (2.1, 3.8 and 4.7. Delivery head, delivery discharge, waste discharge and supply head were utilized to calculate the yield of the hydraulic ram by the equation of D'Aubussion. The maximum yield of the hydraulic ram was obtained for the PVC pipe for the 4.2 m head; for heads higher than 4.2 m the steel pipe was more efficient.

  5. Control strategy for multi-pump emulsion power station in coal mine face

    Institute of Scientific and Technical Information of China (English)

    LI Wen-ying; WEI Jin-hong

    2011-01-01

    Shearer and hydraulic support are matching equipments.To increase the operating speed of the shearer,the following speed of hydraulic support must be increased.This means increasing the volume of flow from emulsion power station.Analyzing the operating characteristics of hydraulic supports,the number of simultaneously operating supports is obtained by means of pressure parameter and time history at a certain time,which is a theory base for development of control system to multi-pump emulsion power station.

  6. 流体属性可变的水压轴向柱塞泵压力流量模型%Pressure and flow characteristic modeling of water hydraulic axial piston pump based on variable fluid properties

    Institute of Scientific and Technical Information of China (English)

    翟江; 周华

    2013-01-01

    Considering cavitation due to the high saturation vapor pressure of water and main fluid properties variation-with pressure, a mathematical model of the dynamic pressure and flow characteristics of a water hydraulic axial piston pump was built. The model was programmed in a MATLAB/Simulink platform and a prototype of water hydraulic pump was simulated as an example. The pressure,flow and cavitation characteristics of the prototype were analyzed based on simulation results. The investigation shows that the average discharge flow of the pump will decrease, obvious cavitation will occur in the cylinder chambers that are in suction process,flow and pressure ripple will be severe when the inlet pressure is low. As the inlet pressure increases, the cavitation in the cylinder chambers will reduce and only occur in transition regions between discharge and suction. The internal leakage of the pump is mainly due to the gap flow of the slipper/swash plate combination and the cylinder block/valve plate combination, and the effects of the piston/cylinder-block can be ignored.%考虑了由于水的高饱和蒸汽压引起的空化及水的主要流体属性随压力变化的特性,建立了水压轴向柱塞泵的压力流量特性模型.以研制的水压轴向柱塞泵样机为例在MATLAB/Simulink环境下编程仿真,分析了泵的压力、流量和空化等特性.研究结果表明:泵入口压力较低时会引起排水流量的下降,在吸水区的缸体柱塞腔内出现明显的空化,泵出口的流量脉动和压力脉动大幅增加;提高泵的入口压力能够减小缸体柱塞腔内的空化程度,此时空化主要发生在由排水向吸水变换的瞬间;泵的内泄漏主要以滑靴副和配流副的泄露为主,柱塞副的泄露可以忽略.

  7. Combining pump-and-treat and physical barriers for contaminant plume control.

    Science.gov (United States)

    Bayer, Peter; Finkel, Michael; Teutsch, Georg

    2004-01-01

    A detailed analysis is presented of the hydraulic efficiency of plume management alternatives that combine a conventional pump-and-treat system with vertical, physical hydraulic barriers such as slurry walls or sheet piles. Various design settings are examined for their potential to reduce the pumping rate needed to obtain a complete capture of a given contaminated area. Using established modeling techniques for flow and transport, those barrier configurations (specified by location, shape, and length) that yield a maximum reduction of the pumping rate are identified assuming homogeneous aquifer conditions. Selected configurations are further analyzed concerning their hydraulic performance under heterogeneous aquifer conditions by means of a stochastic approach (Monte Carlo simulations) with aquifer transmissivity as a random space function. The results show that physical barriers are an appropriate means to decrease expected (mean) pumping rates, as well as the variance of the corresponding pumping rate distribution at any given degree of heterogeneity. The methodology presented can be transferred easily to other aquifer scenarios, provided some basic premises are fulfilled, and may serve as a basis for reducing the pumping rate in existing pump-and-treat systems.

  8. The Thermodynamics Simulation Analysis for the Lubricant Chamber of an Axial Piston Water Hydraulic Pump%轴向柱塞水液压泵润滑油腔的热力学仿真分析

    Institute of Scientific and Technical Information of China (English)

    唐辉; 吴德发; 汤振宇; 李东林; 刘银水

    2012-01-01

    针对油水分离轴向柱塞水液压泵,建立其润滑油腔内各主要运动部件的热力学方程.根据热力学分析的基本理论,创建润滑油腔系统的热平衡方程,并用Matlab软件对其进行数值仿真.根据仿真结果得到润滑油腔内油液的平衡温度,从而分析润滑油腔内的油液粘度变化情况以及润滑油腔内摩擦副的工作状况.研究结果对油水分离水液压泵的设计以及润滑油腔内润滑油的选择具有一定的指导意义和参考价值.%In this paper,a thermodynamic equation of the major moving parts in lubricant chamber of oil-water separation axial piston water hydraulic pump is established,and a heat balance equation of the lubricant chamber system is obtained.Through numerical simulation by using Matlab,the equilibrium temperature of oil in the lubricant chamber is obtained,and the change of viscosity for the oil and the working conditions of the friction pair in the lubricant chamber is analyzed.The research of this article has a guiding significance and reference value to design the oil-water separation water hydraulic pump and the choose lubricating oil of the lubricant chamber.

  9. Design and Analysis of Dumbbell-shaped Seal Ring of Hydraulic Oil Pumping System%液压抽油系统哑铃型密封圈设计与分析

    Institute of Scientific and Technical Information of China (English)

    朱拾东; 张建军; 刘猛; 师峻峰; 赵瑞东

    2013-01-01

    In the hydraulic oil pumping system with water as power fluid,the conventional O-ring and other sealing rings cannot meet the sealing requirements of not collusion for high and low pressure fluid. A new type of dumbbell-shaped seal ring was designed and its sealing mechanism was analyzed. The contact deformation and the contact stress distribution on the contact sealing interface under the action of the liquid pressure were analyzed by finite element analysis software. The results show that the designed dumbbell-shaped sealing structure can meet the sealing requirements of 16 MPa differential pressure of the hydraulic oil pumping system.%  在以水作为动力液介质的液压抽油系统中,常规的O型密封圈及其他密封圈都不能满足高、低压流体之间不串通的密封要求。设计了一种新型的哑铃型密封结构,并分析其密封机制;利用有限元软件分析在液体压力作用下密封圈的接触变形、接触密封界面上的接触应力分布。结果表明,设计的哑铃型密封结构可以满足要求液压抽油系统16 MPa压差的密封要求。

  10. 可调导叶式轴流泵马鞍区水力特性试验研究%Experimental study on hydraulic performance of saddle zone in axial flow pump with adjustable guide vane

    Institute of Scientific and Technical Information of China (English)

    钱忠东; 王凡; 王志远; 周皖

    2013-01-01

    In order to analyze the effects of adjustable guide vane (AGV) on axial pumps working in saddle zone,in the hope of optimizing adjusting laws,performance test of a new axial-flow pump with AGV was carried out on the pump test bed.Q-H,Q-ηand Q-P curves at different guide vane angles were obtained.The effects of AGV on hydraulic performance of the model pump in saddle zone were analyzed.The results show that,at the same flow rate,head and efficiency of axial flow pump increase as guide vane angle is adjusted from 0° to-5°.With AGV,the separation vortex in the flow channel is suppressed effectively; flow regime at pump outlet is optimized obviously; kinetic energy recovery rate is improved.Head and efficiency of the pump are improved by 0.15 m (0.046 9Hd) and 1.93% respectively.The critical flow discharge is decreased by 0.004 94 m3/s and the range of saddle-shaped zone is narrowed by 6.64%,broadening the range of stable working zone.At guide vane angle of-5°-0°,the shaft power changes little.In this experiment,the best values of hydraulic performance obtained are at-5° guide vane angle,but they can be further improved.%为了分析不同导叶安放角对轴流泵在马鞍区工况运行时的影响,探究导叶角度的优化规律,在水泵模型试验台上,对一种新型可调导叶式轴流泵的外特性进行测试,得到不同导叶安放角下H-Q、η-Q、P-Q曲线,分析了导叶安放角对轴流泵马鞍区水力特性的影响.试验结果表明:相同流量工况下轴流泵的扬程和效率随着导叶安放角由0°向-5 °调节而增大,调节导叶安放角,能够有效抑制叶片背面脱流旋涡的扩散,显著改善轴流泵出口的流态,提高动能回收的比例;在马鞍区工况下,扬程最大提升0.15m,为设计扬程的4.69%,效率最大提升1.93%;马鞍区起始点流量向小流量偏移了0.004 94 m3/s,马鞍区范围减小了6.64%,拓宽了轴流泵稳定运行的区域;导叶安放角在-5°~0°的

  11. 沿海电厂露天布置循环水泵出口液控蝶阀的可靠性优化%Circulating Pump Hydraulic Pressure Valve in Power Station Along the Coast Improve Reliability

    Institute of Scientific and Technical Information of China (English)

    王鹏

    2014-01-01

    Circulating water pump outlet Hydraulic Control Butterfly valve is related to the unit itself and even the safe operation of the entire. However compared with the traditional interior layout of the hydraulic control valve the open layout is facing worse operating environment, which brings many hidden dangers into the system's security. Aiming at my plant's problems, this article proposed some suggestions on the selection ,installation and maintenance, from the angle of thermal control.%循环水泵出口液控蝶阀关系到循环水泵自身乃至整台机组的安全运行。但露天布置的液控蝶阀跟传统室内布置的液控蝶阀比,其运行环境比较恶劣,对系统的安全投运带来许多隐患。针对浙江大唐乌沙山发电厂出现的问题,本文从热控角度提出选型、安装、维护等方面的几点建议。

  12. Estimation of hydraulic parameters in a complex porous aquifer system using geoelectrical methods.

    Science.gov (United States)

    Kazakis, N; Vargemezis, G; Voudouris, K S

    2016-04-15

    Geoelectrical methods have been widely used for the estimation of aquifer hydraulic properties. In this study, geoelectrical methods were applied in a lithologically and hydrochemically complex porous aquifer to estimate its porosity, hydraulic conductivity and transmissivity. For this purpose, the electrical resistivity of the aquifer as well as the electrical conductivity of the groundwater was measured in 37 sites and wells. Initially, the Archie's law was used to generate sets of cementation factor (m) and alpha (α) parameter from which the mode values of α=0.98 and m=1.75 are representative of the studied aquifer. The transmissivity of the aquifer varies from 5.1×10(-3) to 3.1×10(-5)m(2)/s, whereas the mean value of its porosity is 0.45. The hydraulic conductivity of the aquifer which was calculated according to Archie's law varies from 2.08×10(-6) to 6.84×10(-5)m/s and is strongly correlated with the pumping test's hydraulic conductivity. In contrast, the hydraulic conductivity which was calculated using Dar-Zarrouk parameters presents lower correlation with the pumping test's hydraulic conductivity. Furthermore, a relation between aquifer resistivity and hydraulic conductivity was established for the studied aquifer to enable the estimation of these parameters in sites lacking data.

  13. A new method of providing pulsatile flow in a centrifugal pump: assessment of pulsatility using a mock circulatory system.

    Science.gov (United States)

    Herreros, Jesús; Berjano, Enrique J; Sales-Nebot, Laura; Más, Pedro; Calvo, Irene; Mastrobuoni, Stefano; Mercé, Salvador

    2008-06-01

    Previous studies have demonstrated the potential advantages of pulsatile flow as compared with continuous flow. However, to date, physiologic pumps have been technically complex and their application has therefore remained in the experimental field. We have developed a new type of centrifugal pump, which can provide pulsatile as well as continuous flow. The inner wall of a centrifugal pump is pulsed by means of a flexible membrane, which can be accurately controlled by means of either a hydraulic or pneumatic driver. The aim of this study was to assess the hydraulic behavior of the new pump in terms of surplus hemodynamic energy (SHE). We conducted experiments using a mock circulatory system including a membrane oxygenator. No differences were found in the pressure-flow characteristics between the new pump and a conventional centrifugal pump, suggesting that the inclusion of the flexible membrane does not alter hydraulic performance. The value of SHE rose when systolic volume was increased. However, SHE dropped when the percentage of ejection time was reduced and also when the continuous flow (programmed by the centrifugal console) increased. Mean flow matched well with the continuous flow set by the centrifugal console, that is, the pulsatile component of the flow was exclusively controlled by the pulsatile console, and was therefore independent of the continuous flow programmed by the centrifugal console. The pulsatility of the new pump was approximately 25% of that created with a truly pulsatile pump.

  14. Method for optimising the energy of pumps

    NARCIS (Netherlands)

    Skovmose Kallesøe, Carsten; De Persis, Claudio

    2011-01-01

    The method involves determining whether pumps (pu1, pu5) are directly assigned to loads (v1, v3) as pilot pumps (pu2, pu3) and hydraulically connected upstream of the pilot pumps. The upstream pumps are controlled with variable speed for energy optimization. Energy optimization circuits are selected

  15. Coupling of high temperature nuclear reactor with chemical plant by means of steam loop with heat pump

    Directory of Open Access Journals (Sweden)

    Kopeć Mariusz

    2017-01-01

    Full Text Available High temperature nuclear reactors (HTR can be used as an excellent, emission-free source of technological heat for various industrial applications. Their outlet helium temperature (700°-900°C allows not only for heat supply to all processes below 600°C (referred to as “steam class”, but also enables development of clean nuclear-assisted hydrogen production or coal liquefaction technologies with required temperatures up to 900°C (referred to as “chemical class”. This paper presents the results of analyses done for various configurations of the steam transport loop coupled with the high-temperature heat pump designed for “chemical class” applications. The advantages and disadvantages as well as the key issues are discussed in comparison with alternative solutions, trying to answer the question whether the system with the steam loop and the hightemperature heat pump is viable and economically justified.

  16. Effect of clocking position of inducer on hydraulic characteristics of centrifugal pump%诱导轮时序位置对离心泵水力性能的影响

    Institute of Scientific and Technical Information of China (English)

    卢金玲; 邓佳; 徐益荣; 冯建军; 罗兴锜

    2015-01-01

    Different circumferential positions of stator/stator, rotor/rotor, stator /rotor have different wake vortex, which has different effects on the downstream blade boundary. This phenomenon is called clocking effect. The clocking effect has been widely used in the radial and axial pneumatic machinery, and the aerodynamic performance has been greatly improved. However, clocking effect is rarely used in hydraulic machinery, especially for hydraulic machinery with inducer. For the viscosity of the water is much larger than that of most gases, large trail vortex may occur at the downstream of vanes of hydraulic machinery, even at low flow velocity. When entering the impeller, this kind of vortex may further develop and mix with each other in the impeller. New vortex may be brought out downstream of the impeller, resulting in a greater impact on overall performance. Thus, the clocking effects may play a more important role in hydraulic machinery than pneumatic machinery. In order to study the influence of clocking effect on centrifugal pump, a single-stage centrifugal pump was selected as the study object, and three-dimensional unsteady viscous numerical method was applied to simulate inner flow in the centrifugal pump at 3 different clocking positions of inducer relative to impeller. The pump mainly consisted of inlet pipe, inducer, impeller, diffuser and outlet pipe. When the angle between reference blade of inducer and reference blade of impeller was 53°, the relative circumferential position was called clocking position 0, named CL0; the clocking position number increased by 1 every increase of 40° clockwise. External characteristics, cavitation characteristics and vibration characteristics were analyzed. It was found that the external characteristics of centrifugal pump were greatly influenced by clocking effects. With the change of clocking position, the head and efficiency of pump first increased and then decreased; the head and efficiency were the highest at CL1

  17. Ground-water system, estimation of aquifer hydraulic properties, and effects of pumping on ground-water flow in Triassic sedimentary rocks in and near Lansdale, Pennsylvania

    Science.gov (United States)

    Senior, Lisa A.; Goode, Daniel J.

    1999-01-01

    Ground water in Triassic-age sedimentary fractured-rock aquifers in the area of Lansdale, Pa., is used as drinking water and for industrial supply. In 1979, ground water in the Lansdale area was found to be contaminated with trichloroethylene, tetrachloroethylene, and other man-made organic compounds, and in 1989, the area was placed on the U.S. Environmental Protection Agency's (USEPA) National Priority List as the North Penn Area 6 site. To assist the USEPA in the hydrogeological assessment of the site, the U.S. Geological Survey began a study in 1995 to describe the ground-water system and to determine the effects of changes in the well pumping patterns on the direction of ground-water flow in the Lansdale area. This determination is based on hydrologic and geophysical data collected from 1995-98 and on results of the simulation of the regional ground-water-flow system by use of a numerical model.Correlation of natural-gamma logs indicate that the sedimentary rock beds strike generally northeast and dip at angles less than 30 degrees to the northwest. The ground-water system is confined or semi-confined, even at shallow depths; depth to bedrock commonly is less than 20 feet (6 meters); and depth to water commonly is about 15 to 60 feet (5 to 18 meters) below land surface. Single-well, aquifer-interval-isolation (packer) tests indicate that vertical permeability of the sedimentary rocks is low. Multiple-well aquifer tests indicate that the system is heterogeneous and that flow appears primarily in discrete zones parallel to bedding. Preferred horizontal flow along strike was not observed in the aquifer tests for wells open to the pumped interval. Water levels in wells that are open to the pumped interval, as projected along the dipping stratigraphy, are drawn down more than water levels in wells that do not intersect the pumped interval. A regional potentiometric map based on measured water levels indicates that ground water flows from Lansdale towards discharge

  18. Assessment of power step performances of variable speed pump-turbine unit by means of hydro-electrical system simulation

    Science.gov (United States)

    Béguin, A.; Nicolet, C.; Hell, J.; Moreira, C.

    2017-04-01

    The paper explores the improvement in ancillary services that variable speed technologies can provide for the case of an existing pumped storage power plant of 2x210 MVA which conversion from fixed speed to variable speed is investigated with a focus on the power step performances of the units. First two motor-generator variable speed technologies are introduced, namely the Doubly Fed Induction Machine (DFIM) and the Full Scale Frequency Converter (FSFC). Then a detailed numerical simulation model of the investigated power plant used to simulate power steps response and comprising the waterways, the pump-turbine unit, the motor-generator, the grid connection and the control systems is presented. Hydroelectric system time domain simulations are performed in order to determine the shortest response time achievable, taking into account the constraints from the maximum penstock pressure and from the rotational speed limits. It is shown that the maximum instantaneous power step response up and down depends on the hydro-mechanical characteristics of the pump-turbine unit and of the motor-generator speed limits. As a results, for the investigated test case, the FSFC solution offer the best power step response performances.

  19. Design of hydraulic output Stirling engine

    Science.gov (United States)

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

    1983-01-01

    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 are designed to endure more than 10 billion cycles, and to withstand the differential pressure load as high as 14 MPa. The projected thermodynamic performance of the hydraulic output version of RE-1000 FPSE is 1.87 kW at 29/7 percent brake efficiency.

  20. 匹配发动机的液压泵复合式控制特性研究%Study on Combined Control for Matching Hydraulic Pumps to Engine

    Institute of Scientific and Technical Information of China (English)

    黄新磊; 胡军科; 陈鹤梅; 罗宁

    2011-01-01

    研究液压系统优化控制问题,针对工程机械的复杂工况经常使得液压泵与发动机扭矩匹配不合理,造成发动机熄火或功率利用过低.为提高系统性能,提出了DA(排量转速控制)与EP(电比例控制)的复合式控制方案,调节泵排量使其扭矩与发动机外特性相适应.建立流量连续方程和力平衡方程复合式控制微分形式的数学模型,并导出其传递函数.在MATLAB/Simulink平台搭建模型,对控制特性进行了仿真研究.结果表明,复合式控制可使液压泵与发动机高效匹配,为发动机的液压系统优化控制提供了科学依据.%Complex working conditions in construction machinery result in the torque mismatch between hydraulic pumps and the engine, which probably leads to engine stalling or poor power utilizing. The control scheme combined EP with DA has been proposed against this, thus pumps' placement is regulated to cope with the engine' s external characteristic. After demonstrating principles of the displacement varying, this paper builds up the dynamic math-ematic model of the combined control in differential form, which deduces the system's block diagram in transfer function. Therefore, the control scheme's simulation is able to be carried out with MATLAB/Simulink. Results of the simulation manifest that the combined control can make hydraulic pumps and engines match well and has effect on pushing construction machinery forwards to high performance of energy saving and reliability.

  1. Hydraulic structures

    CERN Document Server

    Chen, Sheng-Hong

    2015-01-01

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

  2. Hydraulic connection and penstock chambers in the PSP Kops II. Direct crossing from pump- into turbine operation; Hydraulischer Kurzschluss und Druckluftwasserschlosskammern im PSW Kops II. Nahtloser Uebergang vom Pump- in den Turbinenbetrieb

    Energy Technology Data Exchange (ETDEWEB)

    Puerer, E. [Vorarlberger Illwerke AG (VIW), Schruns (Austria)

    2007-04-16

    After a two years' design development phase including the implementation of the approval process and the award of contracts for all major components, the new building of Kopswerk II has been started on the 1st of September 2004. Kopswerk II is a pump storage scheme with an installed capacity of 450 to 510 MW in turbine mode and 450 MW in pumping operation. The conception of this power plant was substantially determined by the modified market conditions since the liberalization of the electricity market. Nowadays the plant is in the third year of construction. The installation of the first turbogenerator unit has advanced and will start-up in at the end of the year 2007. The completion of the total plant with full operation of the three turbogenerator units is planned in the middle of 2008. The erection cost at the end of construction shall be about 370 Mio Euro. (GL)

  3. 核主泵水力性能数值预测的缩比效应研究%Scaling Effect for Hydraulic Performance Prediction of Nuclear Main Pump

    Institute of Scientific and Technical Information of China (English)

    黎义斌; 李仁年; 王秀勇; 胡鹏林; 齐亚楠

    2015-01-01

    In order to improve the hydraulic performance of the nuclear main pump and achieve optimal matching with shielded motor ,based on the scaling model conversion algorithm ,selecting RNG k‐εturbulence model and SIM PLEC algorithm ,unsteady nu‐merical predictions and external characteristic experiments were conducted .The results show that on the flow conditions of 0.4Qd‐0.7Qd ,the head‐flow curves are relatively flat ;on the rated condition ,the predicted value of head is 5% higher than the rated one;the maximum head of the impeller is at the 0.4Qd operating point ,the maximum value of hydraulic efficiency is located at the 0.9Qd operating point ,the simulation value of hydraulic efficiency of the impeller is 5% higher than the experimental one .On small flow rate conditions ,the hydraulic loss of guide vane yields the normal distribution law taking the 0.4Qd condition as the central axis , the maximum value of guide vane hydraulic loss is at the 0.4Qd operating point .On large flow rate conditions ,the mini‐mum hydraulic loss value of the guide vane is at the 1.1Qd operating point .The hydrau‐lic loss of water pressure chamber is in accordance with sinusoidal distribution law ;the peak is located at the vicinity of 0.4Qd operating point and the trough is near the 0.9Qd operating point .%为提高核主泵的整体水力性能,实现与屏蔽电机的最优匹配,基于缩比模型换算法,选取RNG k‐ε湍流模型和SIMPLEC算法,对核主泵进行非定常数值预测及外特性试验。结果表明:在0.4Qd ~0.7Qd流量工况下,扬程‐流量曲线较为平坦;额定工况下,扬程预测值较额定值高5%,叶轮扬程最大值在0.4Qd 工况点,水力效率最大值在0.9Qd 工况点,叶轮水力效率模拟值较试验值高5%;小流量工况下,导叶水力损失呈以0.4Qd 工况点为中轴线的正态分布,水力损失最大值在0.4Qd 工况点;大流量工况下,导叶水力损失最小值在1

  4. Hydraulic Actuator for Ganged Control Rods

    Science.gov (United States)

    Thompson, D. C.; Robey, R. M.

    1986-01-01

    Hydraulic actuator moves several nuclear-reactor control rods in unison. Electromagnetic pump pushes liquid lithium against ends of control rods, forcing them out of or into nuclear reactor. Color arrows show lithium flow for reactor startup and operation. Flow reversed for shutdown. Conceived for use aboard spacecraft, actuator principle applied to terrestrial hydraulic machinery involving motion of ganged rods.

  5. 基于响应面法的离心泵作透平水力和声学性能优化%Hydraulic and acoustic property optimization for centrifugal pump as turbine based on response surface method

    Institute of Scientific and Technical Information of China (English)

    代翠; 孔繁余; 董亮; 汪家琼; 柏宇星

    2015-01-01

    为综合优化离心泵作透平的水力和声学性能,建立了一种基于响应面的离心泵作透平水力和声学性能多目标优化方法。首先在对比分析叶轮几何参数对透平水力和噪声影响的基础上,根据敏感度筛选出对噪声影响显著的关键参数;进而应用响应面方法构造显著变量与多目标函数的响应面多元回归模型,分析影响水力效率与噪声的参数间交互作用;最终以水力效率不降低和总声压级最小为响应目标,兼顾性能与噪声确定最优参数组合,即叶片进口安放角为19.5°,叶片出口安放角为20°,叶片出口宽度为16 mm,叶片包角为92°,叶轮进口直径为101 mm,叶片数为12。对某离心泵作透平多目标优化结果表明,叶轮进口直径、叶片出口宽度、叶片数及叶片包角对内场噪声总声压级影响显著;响应面模型能够反映参数与响应值之间的相关性;经试验验证优化后透平水力效率平均提高了1.98个百分点,总声压级降低了4.95 dBA,表明采用的响应面法能够在不影响透平原有水力性能的前提下改善声学性能。%As a way of energy saving by recovery of residual pressure, centrifugal pump as turbine (PAT) has been widely used in many fields. As PAT is gradually developed for high power, flow-induced noise becomes one of the most important issues that cause negative effect on reliability. In order to improve both hydraulic and acoustic performances of PAT, an optimization method combining sensitivity analysis and response surface was established. Firstly, through comparison of impeller parameter impact on hydraulic and noise performances, the geometric parameters with great influence on acoustic were filtered based on sensitivity analysis. Further more, with the efficiency and A-weighted overall sound pressure level (OASPL) as target, the multiple regression models connecting variables and multi-objective functions

  6. Energy saving in hotels by means of heat pumps application; Ahorro de energia en hoteles mediante la aplicacion de bombas de calor

    Energy Technology Data Exchange (ETDEWEB)

    Romero Paredes R, Hernando; Ambriz G, Juan Jose [Universidad Autonoma Metropolitana, Unidad Iztapalapa (Mexico)

    2005-07-15

    The thermal energy is presented as an alternate saving technology for utilities by means of the acute implementation of heat pumps. The objective is to demonstrate the technical and economical feasibility of the application of commercial heat pumps to installations where the handling of opposite temperatures for the conditioning of a space and/or of a fluid is required. In this article it is described the functioning of a heat pump, its different operation principles or types as well as the large diversity of applications they can have in industry, utilities and residential buildings. As an application example the substitution of an electric boiler by a heat pump is presented in a hotel installation and its differences in performance regarding the environmental conditioning of a nearby area and the heating of swimming pool water are analyzed. [Spanish] Se presenta la energia termica como una tecnologia de ahorro alterna para empresas de servicios valiendose de la implementacion agudizada de bombas de calor. El objetivo es demostrar la factibilidad tecnica y economica de la aplicacion de bombas de calor comerciales a instalaciones donde se requiere la manipulacion de temperaturas opuestas para el acondicionamiento de un espacio y/o un fluido. Se describe el funcionamiento de una bomba de calor, sus diferentes principios de operacion o tipos, asi como la gran diversidad de aplicaciones que pueden tener en la industria, empresas de servicios y edificios residenciales. Como ejemplo de aplicacion se presenta la sustitucion de una caldera electrica por una bomba de calor en una instalacion hotelera y sus diferencias de rendimiento en el calentamiento de agua de alberca y el acondicionamiento ambiental de un area cercana.

  7. Hydraulic fracturing system and method

    Energy Technology Data Exchange (ETDEWEB)

    Ciezobka, Jordan; Salehi, Iraj

    2017-02-28

    A hydraulic fracturing system and method for enhancing effective permeability of earth formations to increase hydrocarbon production, enhance operation efficiency by reducing fluid entry friction due to tortuosity and perforation, and to open perforations that are either unopened or not effective using traditional techniques, by varying a pump rate and/or a flow rate to a wellbore.

  8. Design of hydraulic recuperation unit

    Directory of Open Access Journals (Sweden)

    Jandourek Pavel

    2016-01-01

    Full Text Available This article deals with design and measurement of hydraulic recuperation unit. Recuperation unit consist of radial turbine and axial pump, which are coupled on the same shaft. Speed of shaft with impellers are 6000 1/min. For economic reasons, is design of recuperation unit performed using commercially manufactured propellers.

  9. A Computational Model of Hydraulic Volume Displacement Drive

    Directory of Open Access Journals (Sweden)

    V. N. Pil'gunov

    2014-01-01

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

  10. Hydraulic manipulator research at ORNL

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-03-01

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

  11. Numerical simulation on hydraulic characteristics of diaphragm pump%隔膜泵液力特性的数值模拟

    Institute of Scientific and Technical Information of China (English)

    张洪生; 史有程; 徐波

    2014-01-01

    In order to enrich diaphragm design theory of reciprocating diaphragm pump so as to extend diaphragm fatigue life,a numerical simulation analysis is carried out on the liquid end of a diaphragm pump,and the motion characteristics of diaphragm and the influences of related parameters on the stress in it and the motion itself are investigated throughout.Because the diaphragm is deformable and driven by a unsteady pressure in the liquid end,fluid-structure interaction has to be taken into account in the simulation.The results show that the fluctuation amplitude of stress in the diaphragm is very high in a cycle of diaphragm motion,namely the maximum peak stress is as high as more than five times the minimum peak stress.The stress concentration region is located at the diaphragm edge.It has been observed that this region frequently is subject to fatigue damage in applications.When a pis-ton stroke is less than 50 min-1 ,the diaphragm stress is little affected by it;or the diaphragm can ex-perience a significantly increased stress.The ratio of pump displacement to diaphragm capacity should be lower than 85%,otherwise the diaphragm stress increases very sharply.The methods adopted can handle the change in computational domain caused from the motion of the piston and diaphragm quite well.As a result,an analysis of fluid-structure interaction has been realized for the suction and dis-charge processes of a diaphragm pump.%为丰富往复式隔膜泵隔膜设计理论进而解决隔膜寿命不足的问题,对隔膜泵液力端动态特性进行流固耦合数值模拟计算。结果表明:一个运动周期内隔膜应力脉动幅度很大,最大应力值约为最小应力值5倍;隔膜上边缘为应力集中区域,该结论也符合工程中上边缘为疲劳破坏高发区的事实;活塞冲次不高于50 min-1时对隔膜应力的影响较小,但当活塞冲次较高时隔膜应力增大非常明显;泵排量占隔膜吞吐能力体积分数应低于85

  12. Detection of pump degradation

    Energy Technology Data Exchange (ETDEWEB)

    Greene, R.H.; Casada, D.A.; Ayers, C.W. [and others

    1995-08-01

    This Phase II Nuclear Plant Aging Research study examines the methods of detecting pump degradation that are currently employed in domestic and overseas nuclear facilities. This report evaluates the criteria mandated by required pump testing at U.S. nuclear power plants and compares them to those features characteristic of state-of-the-art diagnostic programs and practices currently implemented by other major industries. Since the working condition of the pump driver is crucial to pump operability, a brief review of new applications of motor diagnostics is provided that highlights recent developments in this technology. The routine collection and analysis of spectral data is superior to all other technologies in its ability to accurately detect numerous types and causes of pump degradation. Existing ASME Code testing criteria do not require the evaluation of pump vibration spectra but instead overall vibration amplitude. The mechanical information discernible from vibration amplitude analysis is limited, and several cases of pump failure were not detected in their early stages by vibration monitoring. Since spectral analysis can provide a wealth of pertinent information concerning the mechanical condition of rotating machinery, its incorporation into ASME testing criteria could merit a relaxation in the monthly-to-quarterly testing schedules that seek to verify and assure pump operability. Pump drivers are not included in the current battery of testing. Operational problems thought to be caused by pump degradation were found to be the result of motor degradation. Recent advances in nonintrusive monitoring techniques have made motor diagnostics a viable technology for assessing motor operability. Motor current/power analysis can detect rotor bar degradation and ascertain ranges of hydraulically unstable operation for a particular pump and motor set. The concept of using motor current or power fluctuations as an indicator of pump hydraulic load stability is presented.

  13. 46 CFR 111.97-5 - Electric and hydraulic power supply.

    Science.gov (United States)

    2010-10-01

    ... by one or more motor-driven hydraulic pumps that can operate from the final source of the emergency lighting and power system. (d) The motor-driven hydraulic pumps must automatically maintain the accumulator... 46 Shipping 4 2010-10-01 2010-10-01 false Electric and hydraulic power supply. 111.97-5...

  14. Período de recuperação do investimento em bomba hidráulica de melhor rendimento em sistemas de bombeamento na tarifa horossazonal verde Investment recovery period in hydraulic pump of better efficiency in pumping systems in the green hourly seasonal tariff for irrigation

    Directory of Open Access Journals (Sweden)

    João L. Zocoler

    2011-04-01

    Full Text Available Neste trabalho, ajustou-se um modelo matemático para quantificar o efeito da variação do rendimento da bomba hidráulica na variação dos custos de um sistema de bombeamento, na estrutura tarifária horossazonal verde (subgrupo A4 e o tempo de recuperação do capital investido no equipamento de maior rendimento. Em seguida, o mesmo foi aplicado a um sistema de bombeamento para suprimento de um sistema de irrigação do tipo pivô central. As opções de rendimento da bomba hidráulica foram: 69,5% (bomba 1, 73% (bomba 2 e 78% (bomba 3, cujos custos de aquisição foram, respectivamente, R$ 6.176,00, R$ 8.479,00 e R$ 15.509,00. Os resultados da aplicação do modelo mostraram que: i a substituição da bomba 1 pela bomba 2 foi viável, sendo o período de recuperação de capital 3,4 anos; ii a substituição da bomba 1 pela bomba 3 foi viável, sendo o período de recuperação de capital 9,2 anos; iii a substituição da bomba 2 pela bomba 3 foi inviável, sendo o período de recuperação de capital 21,1 anos superior ao período de amortização do investimento na avaliação econômica, considerado 15 anos.In this study a mathematical model was adjusted to quantify the effect of the pump efficiency on cost variation of the pumping system in the green hourly seasonal tariff (subgroup A4 - irrigation and the investment recovery period by a more efficient pumping station. Afterwards, the same model was applied in a pumping system supplying a center pivot irrigation machine. The hydraulics pump efficiency options were: 69.5% (pump 1, 73% (pump 2 and 78% (pump 3, with acquisition costs of R$ 6,176.00, R$ 8,479.00 and R$ 15,509.00, respectively. The results of the model applied showed that: i the substitution of pump 1 for 2 was feasible, being the investment recovery period of 3.4 years; ii the substitution of bomb 1 for 3 was feasible, being the investment recovery period of 9.2 years; and iii the substitution of bomb 2 for 3 was unfeasible

  15. Experimental Comparison of Low-temperature Hydraulic Heating Floor and Heat Pump Air-conditioning%低温热水地板与热泵空调器采暖测试对比分析

    Institute of Scientific and Technical Information of China (English)

    王文; 何雪冰; 陈建苹; 张素云; 刘宪英

    2001-01-01

    通过对重庆地区一住宅内低温热水地板供暖系统的测试,分析对比了该系统与热泵空调器采暖方式对室内热舒适性的影响及运行费用的差别,同时对地板辐射和对流散热的综合效果进行分析,表明在长江流域等非采暖地区应用地板辐射采暖的可行性及优越性。%In this paper the low-temperature hydraulic floor heating system of a residence in Chongqing was tested. The influence of this system and the heat pump air conditioning system on indoor thermal comfort and operation cost was analyzed and compared. The effect of heat dissipation by radiation and convention of the floor was analyzed. It shows the feasibility and advantage of floor heating system in Yangtse River Region.

  16. HYDRAULIC ELEVATOR INSTALLATION ESTIMATION FOR THE WATER SOURCE WELL SAND-PACK CLEANING UP

    Directory of Open Access Journals (Sweden)

    V. V. Ivashechkin

    2016-01-01

    Full Text Available The article offers design of a hydraulic elevator installation for cleaning up water-source wells of sand packs. It considerers the installation hydraulic circuit according to which the normal pump feeds the high-level tank water into the borehole through two parallel water lines. The water-jet line with washing nozzle for destroying the sand-pack and the supply pipe-line coupled with the operational nozzle of the hydraulic elevator containing the inlet and the supply pipelines for respectively intaking the hydromixture and removing it from the well. The paper adduces equations for fluid motion in the supply and the water-jet pipelines and offers expressions for evaluating the required heads in them. For determining water flow in the supply and the water-jet pipe lines the author proposes to employ graphical approach allowing finding the regime point in Q–H chart by means of building characteristics of the pump and the pipe-lines. For calculating the useful vertical head, supply and dimensions of the hydraulic elevator the article employs the equation of motion quantity with consistency admission of the motion quantity before and after mixing the flows in the hydraulic elevator. The suggested correlations for evaluating the hydraulic elevator efficiency determine the sand pack removal duration as function of its sizes and the ejected fluid flow rate. A hydraulic-elevator installation parameters estimation example illustrates removing a sand pack from a water-source borehole of 41 m deep and 150 mm diameter bored in the village of Uzla of Myadelsk region, of Minsk oblast. The working efficiency of a manufactured and laboratory tested engineering prototype of the hydraulic elevator installation was acknowledged in actual tests at the indicated borehole site. With application of graphical approach, the suggested for the hydraulic elevator installation parameters calculation procedure allows selecting, with given depth and the borehole diameter

  17. Hydraulic Structures

    Data.gov (United States)

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

  18. Hydraulic mining method

    Science.gov (United States)

    Huffman, Lester H.; Knoke, Gerald S.

    1985-08-20

    A method of hydraulically mining an underground pitched mineral vein comprising drilling a vertical borehole through the earth's lithosphere into the vein and drilling a slant borehole along the footwall of the vein to intersect the vertical borehole. Material is removed from the mineral vein by directing a high pressure water jet thereagainst. The resulting slurry of mineral fragments and water flows along the slant borehole into the lower end of the vertical borehole from where it is pumped upwardly through the vertical borehole to the surface.

  19. Mechatronic Hydraulic Drive with Regulator, Based on Artificial Neural Network

    Science.gov (United States)

    Burennikov, Y.; Kozlov, L.; Pyliavets, V.; Piontkevych, O.

    2017-06-01

    Mechatronic hydraulic drives, based on variable pump, proportional hydraulics and controllers find wide application in technological machines and testing equipment. Mechatronic hydraulic drives provide necessary parameters of actuating elements motion with the possibility of their correction in case of external loads change. This enables to improve the quality of working operations, increase the capacity of machines. The scheme of mechatronic hydraulic drive, based on the pump, hydraulic cylinder, proportional valve with electrohydraulic control and programmable controller is suggested. Algorithm for the control of mechatronic hydraulic drive to provide necessary pressure change law in hydraulic cylinder is developed. For the realization of control algorithm in the controller artificial neural networks are used. Mathematical model of mechatronic hydraulic drive, enabling to create the training base for adjustment of artificial neural networks of the regulator is developed.

  20. Experimental Investigation of a Rectangular Airlift Pump

    Directory of Open Access Journals (Sweden)

    I. I. Esen

    2010-01-01

    Full Text Available Hydraulic performance of an airlift pump having a rectangular cross-section 20 mm × 80 mm was investigated through an experimental program. The pump was operated at six different submergence ratios and the liquid flow rate was measured at various flowrates of air injected. The effectiveness of the pump, defined as the ratio of the mass of liquid pumped to the mass of air injected, was determined as a function of the mass of air injected for different submergence ratios. Results obtained were compared with those for circular airlift pumps using an analytical model for circular pumps. Effectiveness of the rectangular airlift pump was observed to be comparable to that of the circular pumps. Hydraulic performance of the rectangular airlift pump investigated was then described by a set of semilogarithmic empirical equations.

  1. Control arrangement for the actuation of hydraulic consumers

    Energy Technology Data Exchange (ETDEWEB)

    Kussel, W.; Dettmers, M.; Weirich, W.

    1988-11-09

    An arrangement for controlling the actuation of hydraulic consumers, by selectively connecting the consumers to hydraulic pressure and return lines; the control arrangement comprising a respective hydraulically operated directional control valve associated with each of the hydraulic consumers, a respective electro-magnetically operated pre-control valve associated with each of the hydraulic directional control valves, and further electro-magnetically operated directional control valve means associated with the pre-control valves, each of the hydraulic consumers being connectible to the hydraulic pressure or return lines via the associated hydraulically operated directional control valve which is actuatable by a hydraulic control line leading from the output of the associated pre-control valve, wherein the inputs of the pre-control valves are connected directly to the hydraulic return line and indirectly, via the further control valve means, to the hydraulic return line or to a hydraulic control pressure line.

  2. Estimating Parameters of Aquifer Heterogeneity Using Pumping Tests - a Paradigm for Field Applications

    Science.gov (United States)

    Zech, Alraune; Arnold, Sven; Schneider, Christoph; Attinger, Sabine

    2013-04-01

    The vast majority of natural aquifers are characterized by heterogeneity which can be statistically represented by parameters such as geometric mean, correlation lengths and variance of hydraulic conductivity. Head measurements of pumping tests are commonly used to estimate the hydraulic properties of porous media. Zech et al. 2012, WRR introduced the effective well flow method allowing a direct parameter estimation from steady state pumping test drawdowns. However, in contrast to simulated pumping tests, the number and spatial distribution of piezometers is limited for on-site pumping tests. We analyze the capability of the effective well flow method to provide accurate and confident parameter estimates of a heterogeneous aquifer under limited availability of head measurements. We use simulated pumping tests to systematically reduce sampling size while also determining the accuracy and uncertainty of estimates at each level of data availability. The same analytical solution is then applied to estimate the statistical parameters of a fluvial heterogeneous aquifer at the test site Horkheimer Insel, Germany. We thereby close the gap between theoretical and practical application of an analytical solution describing three-dimensional steady state well flow. Our findings indicate how accuracy and uncertainty of estimated parameters, like mean conductivities and correlation lengths correlate to number and spatial distribution of head measurements. The results provide valuable implications regarding the conceptual design of ground water pumping tests and the predictive power of established pumping test sites.

  3. Analysis on Hydraulic Performance of Reversible Vertical Pumping System Based on CFX%基于CFX的双向立式轴流泵装置水力性能分析

    Institute of Scientific and Technical Information of China (English)

    杨帆; 刘超; 汤方平

    2012-01-01

    The investigation of the three-dimensional fluid flow inside a reversible pumping system was made based on the Reynolds time-averaged Navier-Stokes equations, the RNG k-e turbulent flow model and the law of the wall. The performance calculations were made at 9 operation points within flow rates range 240-460L/s under the rated rotating speed. The effects of flow guide cone on the hydraulic performance of inlet passage and the effects of guide vane on the performance of pumping system were analyzed. To verify the accuracy and reliability of the calculation results,a model test was conducted. The singular point which caused the submerse vortex under pump suction were eliminated by flow guide cone. With the flow guide cone, the axial velocity distribution uniformity at the exit section of suction passage was improved by 0.5-0.8 percentage points,and velocity-weighted average swirl angle increased by 0. 3°-1. 28°. Flow guide cone has little effect on water flow by gravity. Diffuse shape guide vane can better recover circulation out from impeller at large flow rate, therefore the efficiency of pumping system increased obviously.%为分析双向立式轴流泵装置的内部流动结构并进行性能预测,应用三维紊流Navier-Stokes、RNG κ-ε湍流模型和壁面定律对泵装置进行全流场数值模拟研究,共计算了额定转速下240—460L/s流量范围内的9个工况点.分析了导水锥对迸水流道水力性能的影响及导叶体对装置性能的影响,并通过泵装置模型试验对预测的外特性结果进行验证.研究表明,加设导水锥可消除喇叭口下的奇点,避免附底涡的产生,加设导水锥后进水流道出口断面轴向速度分布均匀度提高0.5-0.8个百分点,速度加权平均角提高了0.3°-1.28°.导水锥对自流工况的影响很小.大流量工况时扩散导叶对叶轮出口环量的回收效果优于常规导叶,泵装置效率明显提高.

  4. Hydraulics and pneumatics

    CERN Document Server

    Parr, Andrew

    2006-01-01

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

  5. Faint Fault Feature Extraction of Hydraulic Pump Based on Adaptive EEMD-Enhancement Factor%基于EEMD-增强因子自适应的液压泵微弱故障特征提取

    Institute of Scientific and Technical Information of China (English)

    王余奎; 李洪儒; 许葆华

    2014-01-01

    针对斜盘式轴向柱塞泵微弱故障特征难以提取的问题,提出了一种基于EEMD-增强因子自适应的液压泵微弱故障特征提取方法。对故障信号EEMD分解得到一组IMFs,采用增强因子作为各IMF权值合成信号以突出故障特征并抑制不相关成分;对合成信号EEMD分解,用敏感因子筛选出最能够表征故障信息的IMFs分量重构信号;对重构信号做Hil-bert变换求得包络谱,分析包络谱诊断出具体故障。仿真信号和液压泵实测信号的分析结果均很好地验证了该方法的有效性和优越性。%Aimed at the problem of difficult to extract the faint fault feature of axial plunger piston pump of inclined disk type,a method based on adaptive EEMD-enhancement factor was presented. Fault signals were decomposed into a group of intrinsic mode func-tions (IMFs)with ensemble empirical mode decomposition (EEMD),as to highlight the fault characteristic and inhibit unrelated ele-ments by using the enhancement factor of IMF as its weight to synthetic signal. The synthetic signal was decomposed with EEMD opera-tion,and the sensitive component was constructed with the IMFs which were the best represents of fault information as they were select-ed according to their sensitive factor. The envelope spectral of reconstructed signal was obtained by executing Hilbert transform to it, and the actual fault was diagnosed by the analysis of the gained envelope spectral. The validity and superiority of the method are dem-onstrated by the analysis results of simulation signal and the engineering measured data of hydraulic pump.

  6. Hydraulic balance by means of electromotoric HKV drives for dynamic load profiles; Hydraulischer Abgleich mittels elektromotorischer HKV-Antriebe fuer dynamische Lastprofile

    Energy Technology Data Exchange (ETDEWEB)

    Szendrei, Danny [Westsaechsische Hochschule Zwickau (Germany)

    2010-07-01

    To date, measures and concepts for saving energy become more and more important. The development of prices for conventional energy sources forces public and private households and businesses to changes in consumer behaviour and purchasing behaviour. Due to the structural infrastructure, the housing construction in communes strongly is affected by these developments. Nearly 35 % of the total energy demand in Europe account for heating of buildings generally. The most common type of heating system for heating of residential buildings is the central hot water heating in the two-tube version. It is assumed that nearly 90 % of the operated plants have a hydraulic unbalance. Additionally, balanced heating systems fulfil the desired efficiency only under certain, structural design conditions. The integration of the control of heating systems in the smart home infrastructure or KNX infrastructure enables a building-independent, tunable heat supply between buildings and consumption acquisition. The hydraulic system loads can be optimized simultaneously via the direct access to the control value. Thus, a homogeneous mass distribution over the plant can be guaranteed which is derived from the dynamic needs of the system users. These heat loads are calculated by the KNX system and the application of HeatingControl.

  7. Fault Analysis and Improvement of Hydraulic-controlled Butterfly-valve Control System of Main Pump Outlet of Wanjiazhai YRDP(Yellow River Diversion Project)%万家寨引黄工程主泵出口液控蝶阀控制系统故障分析与改进

    Institute of Scientific and Technical Information of China (English)

    李珍珍

    2014-01-01

    山西省万家寨引黄工程一期泵站泵组出水侧液控蝶阀控制系统采用传统的接触式机械行程开关,由于蝶阀设备运行在大振动、高潮湿环境下,接触式行程开关损坏频度较高,经常导致液控蝶阀行程控制失效或错误,致使泵组非正常停运。在分析液控蝶阀行程开关故障原因的基础上,提出采用非接触式磁控开关进行技术改造的方案,工程实践证明改造工作较好地解决了液控蝶阀的行程控制问题。%The hydraulic-controlled butterfly-valve control system mounted on pump outlet side in the pumping station of Shanxi Wanjiazhai YRDP phase 1 is controlled by the traditional mechanical contact travel switch. The butterfly-valve operates in large vibration and high humidity environment, the contact travel switch is damaged frequently, often leading to the failures and mistakes of the travel control of hydraulic-controlled butterfly-valve, and causing the the abnormal shutdown of the pump unit. Based on analyzing the reasons of the faults of the travel switch of hydraulic-controlled valve, this paper puts forward a technical transformation scheme of adopting the non-contact magnetic-controlled switch. The engineering practice proves that the technical transformation has better solved the problem of the travel control of hydraulic-control butterfly-valve.

  8. Human Aorta Is a Passive Pump

    Science.gov (United States)

    Pahlevan, Niema; Gharib, Morteza

    2012-11-01

    Impedance pump is a simple valveless pumping mechanism that operates based on the principles of wave propagation and reflection. It has been shown in a zebrafish that a similar mechanism is responsible for the pumping action in the embryonic heart during early stages before valve formation. Recent studies suggest that the cardiovascular system is designed to take advantage of wave propagation and reflection phenomena in the arterial network. Our aim in this study was to examine if the human aorta is a passive pump working like an impedance pump. A hydraulic model with different compliant models of artificial aorta was used for series of in-vitro experiments. The hydraulic model includes a piston pump that generates the waves. Our result indicates that wave propagation and reflection can create pumping mechanism in a compliant aorta. Similar to an impedance pump, the net flow and the flow direction depends on the frequency of the waves, compliance of the aorta, and the piston stroke.

  9. Transient Hydraulic Characteristics of Nuclear Reactor Coolant Pump in Variable Flow Transient Process%核主泵变流量过渡过程瞬态水力特性研究

    Institute of Scientific and Technical Information of China (English)

    王秀礼; 袁寿其; 朱荣生; 付强; 俞志君

    2013-01-01

    For the study on the transient hydraulic characteristics and internal flow mechanism of the nuclear reactor coolant pump in the transient process from design operation conditions to off-design conditions,the variable flow transient characteristics of centrifugal pump impeller passageway were simulated by using CFX software.The results show that during the variable flow transition,the distribution of pressure pulsation of the nuclear reactor coolant pump along the circumference direction is nonuniform.The pressure pulsation trends to rise gradually to reach the maximum value and then fall,basically following a sine-shape changing law.The times of transient pressure fluctuation change are equal to the times of rotor-stator interference between the vane and the guide vane.The closer monitoring point to the intersection surface between the vane and the guide blade is,the greater the pressure fluctuation is.Because of the attack angle,the speed of the impeller passageway first falls and then rises.The guide vane not only transfers the kinetic energy to pressure energy,but also effectively reduces the pressure pulsation amplitude.During the transition to small flow,flow reducing causes the secondary backflow to occur near the outlet of impeller and in turn leads the amplitude of flow velocity variation in the flow channel of impeller to increase with flow decrease.%为研究核主泵从设计工况向非设计工况过渡过程的瞬态水力特性及内部流动机理,应用计算流体力学软件CFX对核主泵叶轮流道内的变流量瞬态流动特性进行数值模拟计算.研究结果表明:变流量过渡时,核主泵的压力脉动沿圆周方向分布并不均匀,其变化趋势是逐渐上升到最大值后又降低,基本呈正弦变化规律,瞬态压力波动变化次数等于叶片与导叶片数之间的动静干涉次数,监测点越靠近叶片与导叶交界面,压力波动越大;由于冲角的存在造成叶轮流道内的速度呈先下降后

  10. Underground pumped hydroelectric storage

    Science.gov (United States)

    Allen, R. D.; Doherty, T. J.; Kannberg, L. D.

    1984-07-01

    Underground pumped hydroelectric energy storage was conceived as a modification of surface pumped storage to eliminate dependence upon fortuitous topography, provide higher hydraulic heads, and reduce environmental concerns. A UPHS plant offers substantial savings in investment cost over coal-fired cycling plants and savings in system production costs over gas turbines. Potential location near load centers lowers transmission costs and line losses. Environmental impact is less than that for a coal-fired cycling plant. The inherent benefits include those of all pumped storage (i.e., rapid load response, emergency capacity, improvement in efficiency as pumps improve, and capacity for voltage regulation). A UPHS plant would be powered by either a coal-fired or nuclear baseload plant. The economic capacity of a UPHS plant would be in the range of 1000 to 3000 MW. This storage level is compatible with the load-velocity requirements of a greater metropolitan area with population of 1 million or more.

  11. Investigation of the Hydrodynamics of Sweep Blade in Hi-Speed Axial Fuel Pump Impeller

    Directory of Open Access Journals (Sweden)

    Ran Tao

    2013-01-01

    Full Text Available Fuel pump is a crucial component in aircraft engine ignition system. For the hi-speed axial fuel pumps, rotating stall triggers vortex and affects the operation stability and security. Sweep blade is widely used to solve the stability problems in aerodynamics field. Investigation on the hydrodynamics was conducted in this study. Based on the typical straight blade pump, positive and negative sweep blade pumps were modeled. With the large eddy simulation method, CFD simulations were conducted to calculate and analyze the flow characteristics in the pump models. To verify the simulation, experiments were also launched on the hydraulic test rig. Results show that the vortex occurs at the suction surface of blade and gathers near the blade tip region. Positive sweep blade is effective to reduce the hydraulic losses by driving the stalled fluid into the mid-part of blade. By applying the positive sweep blade on the axial fuel pump, the instability operating region will be diminished. Adopting sweep blade provides an effective means for stability and security of axial fuel pumps.

  12. Influence of pumping operational schedule on solute concentrations at a well in randomly heterogeneous aquifers

    Science.gov (United States)

    Libera, Arianna; de Barros, Felipe P. J.; Guadagnini, Alberto

    2017-03-01

    We investigate the way diverse groundwater extraction strategies affect the history of solute concentration recovered at a pumping well while taking into account random spatial variability of the system hydraulic conductivity. Considering the joint effects of spatially heterogeneous hydraulic conductivity and temporally varying well pumping rates leads to a realistic evaluation of groundwater contamination risk at the pumping well location. We juxtapose the results obtained when the pumping well extracts a given amount of water operating (a) at a uniform pumping rate and (b) under a transient regime. The analysis is performed within a numerical Monte Carlo framework. Our results show that contaminant concentration breakthrough curves (BTCs) at the well are markedly affected by the transient pumping strategy according to which the well is operated. Our results document the occurrence in time of multiple peaks in the mean and variance of flux-averaged concentrations at the extraction well operating at a transient rate. Our findings suggest that lowest and largest values of mean and variance of flux-averaged concentration at the well tend to occur at the same time. We show that uncertainty associated with detected BTCs at the well increases for pumping regimes displaying a high degree of temporal variability. As such, the choice of the type of engineering control to the temporal sequence of pumping rates could represent a key factor to drive quantification of uncertainty of the contaminant concentration detected at the well. It is documented that pumping rate fluctuations induce a temporally oscillating risk pattern at the well, thus suggesting that the selection of a dynamic pumping regime has a clear influence on the temporal evolution of risk at the well.

  13. Study on Vickers 20VQ5 High-Pressure Pump Bench Evaluation Method for the Oxidation Durability of Hydraulic Oils%液压油氧化耐久性Vickers 20VQ5高压泵台架评定方法研究

    Institute of Scientific and Technical Information of China (English)

    黄胜军; 王泽恩

    2012-01-01

    To study the oxidation durability of hydraulic oils,the Vickers 20VQ5 high pressure vane pump test-bed system and hydraulic oil oxidation durability evaluation method were designed to do air entrainment test under high temperature and high pressure.The situation of oil viscosity,acid value increase and sludge formation was investigated.Reference oil experiment showed that the bench system keeps smooth operation,and can be used to distinguish different hydraulic oil oxidation durability and sludge formation trend,and can meet the testing and evaluation requirements of the development of long-lived hydraulic oil new products.%为考察液压油的氧化耐久性能,设计建立了Vickers 20VQ5高压叶片泵台架系统及液压油氧化耐久性评定方法,在高温、高压下进行空气夹带试验。考察油品黏度变化、酸值增加和油泥生成情况。参比油实验表明,台架运行平稳,能较好地区分不同液压油品氧化耐久性能和油泥生成趋势,满足长寿命液压油新产品开发的试验评定需求。

  14. Examples of oil cavitation erosion in positive displacement pumps

    Science.gov (United States)

    Halat, J. A.; Ellis, G. O.

    1974-01-01

    The effects of cavitation flow on piston type, positive displacement, hydraulic pumps are discussed. The operating principles of the pump and the components which are most subject to erosion effects are described. The mechanisms of cavitation phenomena are identified from photographic records. Curves are developed to show the solubility of air in water, oil-water emulsion, and industrial hydraulic oil.

  15. DESIGN AND CONSTRUCTION OF A HYDRAULIC PISTON

    OpenAIRE

    Santos De La Cruz, Eulogio; Universidad Nacional Mayor de San Marcos; Rojas Lazo, Oswaldo; Universidad Nacional Mayor de San Marcos; Yenque Dedios, Julio; Universidad Nacional Mayor de San Marcos; Lavado Soto, Aurelio; Universidad Nacional Mayor de San Marcos

    2014-01-01

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

  16. Model tests on a semi-axial pump turbine

    Energy Technology Data Exchange (ETDEWEB)

    Strohmer, F.; Horacek, G.

    1984-03-01

    Due to their good hydraulic characteristic semi-axial pump turbines are used in the medium head range of pumped storage plants. This paper describes model tests performed on a semiaxial pump turbine model and shows the results of these tests. The aim of the model tests was the optimization of the hydraulic water passage, the measurement of the hydraulic characteristics over the whole operating range, the investigation of the cavitation behaviour, the investigation of the hydraulic forces and torques as well as the proof of the values guaranteed to the customer.

  17. Determining the Conditions for the Hydraulic Impacts Emergence at Hydraulic Systems

    Directory of Open Access Journals (Sweden)

    Mazurenko A.S.

    2017-08-01

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

  18. The Potential Impacts of Hydraulic Fracturing on Agriculture

    National Research Council Canada - National Science Library

    Beng Ong

    2014-01-01

    Hydraulic fracturing (or “fracking”) is a method of extracting oil and natural gas trapped in deep rock layers underground by pumping water, sand, and other chemicals/additives at high pressures into a well drilled vertically...

  19. 7 CFR 2902.28 - Stationary equipment hydraulic fluids.

    Science.gov (United States)

    2010-01-01

    ... formulated for use in stationary hydraulic equipment systems that have various mechanical parts, such as cylinders, pumps, valves, pistons, and gears, that are used for the transmission of power (and also...

  20. Pumps; Pumpen

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, H. [Gesellschaft fuer Praktische Energiekunde e.V., Muenchen (Germany). Forschungsstelle fuer Energiewirtschaft; Hellriegel, E. [Gesellschaft fuer Praktische Energiekunde e.V., Muenchen (Germany). Forschungsstelle fuer Energiewirtschaft; Pfitzner, G. [Gesellschaft fuer Praktische Energiekunde e.V., Muenchen (Germany). Forschungsstelle fuer Energiewirtschaft

    1994-11-01

    The technical features of commercial pump types are described with regard to their technical, energy-related and economic parameters, and characteristic data are presented in the form of data sheets. This is to provide a basis for a comparative assessment of different technologies and technical variants. The chapter `System specifications` describes the various fields of application of pumps and the resulting specific requirements. The design and function of the different pump types are described in `Technical description`. `System and plant description dscribes the design and adaptation of pumps, i.e. the adaptation of the plant data to the system requirements. `Data compilation` provides a survey of the types and systematics of the compiled data as well as a decision aid for selecting the pumps best suited to the various applications. The `Data sheet` section describes the structure and handling of the data sheets as well as the data contained therein. The data sheets are contained in the apapendix of this report. The section `General analysis` compares typical technical, energy-related and economic characteristics of the different pump types. This is to enable a rough comparison of pump types and to facilitate decisions. The chapter `Example` illustrates the use of the data sheets by means of a selected example. (orig./GL) [Deutsch] Die vorliegende Arbeit hat zum Ziel, Technik seriengefertigter und marktgaengiger Pumpen in typisierter Form hinsichtlich ihrer technischen, energetischen und wirtschaftlichen Parameter zu beschreiben und ihre charakteristischen Kennwerte in Datenblaettern abzubilden. Damit wird ein grundlegendes Instrument fuer die vergleichende Beurteilung unterschiedlicher Techniken bzw. Technikvarianten hinsichtlich energetischer und wirtschaftlicher Kriterien geschaffen. Im Abschnitt `Systemanforderungen` erfolgt die Beschreibung der einzelnen Anwendungsbereiche fuer Pumpen mit den speziellen daraus resultierenden Anforderungen. Der Aufbau und

  1. Applied hydraulic transients

    CERN Document Server

    Chaudhry, M Hanif

    2014-01-01

    This book covers hydraulic transients in a comprehensive and systematic manner from introduction to advanced level and presents various methods of analysis for computer solution. The field of application of the book is very broad and diverse and covers areas such as hydroelectric projects, pumped storage schemes, water-supply systems, cooling-water systems, oil pipelines and industrial piping systems. Strong emphasis is given to practical applications, including several case studies, problems of applied nature, and design criteria. This will help design engineers and introduce students to real-life projects. This book also: ·         Presents modern methods of analysis suitable for computer analysis, such as the method of characteristics, explicit and implicit finite-difference methods and matrix methods ·         Includes case studies of actual projects ·         Provides extensive and complete treatment of governed hydraulic turbines ·         Presents design charts, desi...

  2. Hydraulic drive and control system of the cone collecting robot

    Institute of Scientific and Technical Information of China (English)

    Kong Qinghua; Liu Jinhao; Lu Huaimin

    1999-01-01

    This paper describes the basic structure and design and operation principle of the hydraulic drive and control system with two pumps and two circuits. The manipulator of the cone collecting robot designed is full driven by hydraulic, which has five freedoms. The computer and electrohydraulic proportion velocity regulating valve were installed to realize open loop serve control for reducing cost and easy application.

  3. Estimation of ground water hydraulic parameters

    Energy Technology Data Exchange (ETDEWEB)

    Hvilshoej, Soeren

    1998-11-01

    The main objective was to assess field methods to determine ground water hydraulic parameters and to develop and apply new analysis methods to selected field techniques. A field site in Vejen, Denmark, which previously has been intensively investigated on the basis of a large amount of mini slug tests and tracer tests, was chosen for experimental application and evaluation. Particular interest was in analysing partially penetrating pumping tests and a recently proposed single-well dipole test. Three wells were constructed in which partially penetrating pumping tests and multi-level single-well dipole tests were performed. In addition, multi-level slug tests, flow meter tests, gamma-logs, and geologic characterisation of soil samples were carried out. In addition to the three Vejen analyses, data from previously published partially penetrating pumping tests were analysed assuming homogeneous anisotropic aquifer conditions. In the present study methods were developed to analyse partially penetrating pumping tests and multi-level single-well dipole tests based on an inverse numerical model. The obtained horizontal hydraulic conductivities from the partially penetrating pumping tests were in accordance with measurements obtained from multi-level slug tests and mini slug tests. Accordance was also achieved between the anisotropy ratios determined from partially penetrating pumping tests and multi-level single-well dipole tests. It was demonstrated that the partially penetrating pumping test analysed by and inverse numerical model is a very valuable technique that may provide hydraulic information on the storage terms and the vertical distribution of the horizontal and vertical hydraulic conductivity under both confined and unconfined aquifer conditions. (EG) 138 refs.

  4. Power management in hydraulically actuated mobile equipment

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen; Andersen, Torben Ole; Hansen, Michael Rygaard

    2008-01-01

    The focus of the current paper is on the control of hydraulic systems when utilizing the advances that electronic control may bring with regard to power management, prioritized flow sharing and anti-stall, arising from being able to control both pump, valves and engine electronically. A simple mo...

  5. Downwell pump reliability: Geothermal experience update: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, P.F.

    1988-01-01

    Geothermal resources with temperatures between 250/sup 0/ and 360/sup 0/F (121/sup 0/C and 182/sup 0/C) are prime candidates for binary-cycle power generation, and constitute about 80% of the power-capable resources in the United States. The successful exploitation of these resources requires reliable high-capacity downwell brine production pumps, but earlier experience showed that high-capacity, high-temperature geothermal production pumps had many problems which resulted in a mean time-to-failure (MTTF) of less than 1000 h. However, steady progress has been made since 1981, and a large body of experience has been acquired by three geothermal binary plants. This survey of high-temperature geothermal downwell pump users and manufacturers updates a prior survey (AP-3572) completed in early 1983. This survey traces the development of lineshaft pump technology from the late 1970s to the present (mid-1987), detailing the advances in design, materials selection, and operating practices. Case histories of 72 lineshaft pumps installed at three geothermal binary plants since late 1981 are documented, including some detailed cause of failure reports. In the recent past, pump lives in excess of 7000 h have become common, but a high continuing rate of premature failures resulted in a mean time-to-failure (MTTF) of about 5000 h. Based on recent advances which appear likely to eliminate most premature failures, the estimated near-term MTTF will be on the order of 8000 h. The survey found almost no development of high-temperature geothermal electric submersible pumps (ESP's) or close-coupled downwell hydraulic turbopumps, and concluded that considerable development and demonstration will be needed before these technologies are able to compete with existing high-temperature geothermal lineshaft pump technology. 36 refs., 10 figs., 25 tabs.

  6. An evaluation of calculation procedures affecting the constituent factors of equivalent circulating density for drilling hydraulics

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, William J.

    1996-12-31

    This Dr. ing. thesis covers a study of drilling hydraulics offshore. The purpose of drilling hydraulics is to provide information about downhole pressure, suitable surface pump rates, the quality of hole cleaning and optimum tripping speeds during drilling operations. Main fields covered are drilling hydraulics, fluid characterisation, pressure losses, and equivalent circulating density. 197 refs., 23 figs., 22 tabs.

  7. Cavitation Effects in Centrifugal Pumps- A Review

    Directory of Open Access Journals (Sweden)

    Maxime Binama

    2016-05-01

    Full Text Available Cavitation is one of the most challenging fluid flow abnormalities leading to detrimental effects on both the centrifugal pump flow behaviors and physical characteristics. Centrifugal pumps’ most low pressure zones are the first cavitation victims, where cavitation manifests itself in form of pitting on the pump internal solid walls, accompanied by noise and vibration, all leading to the pump hydraulic performance degradation. In the present article, a general description of centrifugal pump performance and related parameters is presented. Based on the literature survey, some light were shed on fundamental cavitation features; where different aspects relating to cavitation in centrifugal pumps were briefly discussed

  8. High efficient heat pump system using storage tanks to increase COP by means of the ISEC concept - Part 1: Model validation

    DEFF Research Database (Denmark)

    Rothuizen, Erasmus; Elmegaard, Brian; Markussen, Wiebke B.

    2015-01-01

    The purpose of the ISEC concept is to provide a high-efficient heat pump system for hot water production.The ISEC concept uses two storage tanks for the water, one discharged and one charged. Hot water for theindustrial process is tapped from the charged tank, while the other tank is charging....... Charging is done bycirculating the water in the tank through the condenser of a heat pump several times and thereby graduallyheating the water. The charging is done with a higher mass flow rate than the discharging to reach severalcirculations of the water during the time frame of one discharging....... This result in a lower condensingtemperature than if the water was heated in one step. Two test setups were built, one to test the performanceof the heat pump gradually heating the water and one to investigate the stratification in the storage tanks.Furthermore, a dynamic model of the system was implemented...

  9. Simulation model of a variable-speed pumped-storage power plant in unstable operating conditions in pumping mode

    Science.gov (United States)

    Martínez-Lucas, G.; Pérez-Díaz, J. I.; Sarasúa, J. I.; Cavazzini, G.; Pavesi, G.; Ardizzon, G.

    2017-04-01

    This paper presents a dynamic simulation model of a laboratory-scale pumped-storage power plant (PSPP) operating in pumping mode with variable speed. The model considers the dynamic behavior of the conduits by means of an elastic water column approach, and synthetically generates both pressure and torque pulsations that reproduce the operation of the hydraulic machine in its instability region. The pressure and torque pulsations are generated each from a different set of sinusoidal functions. These functions were calibrated from the results of a CFD model, which was in turn validated from experimental data. Simulation model results match the numerical results of the CFD model with reasonable accuracy. The pump-turbine model (the functions used to generate pressure and torque pulsations inclusive) was up-scaled by hydraulic similarity according to the design parameters of a real PSPP and included in a dynamic simulation model of the said PSPP. Preliminary conclusions on the impact of unstable operation conditions on the penstock fatigue were obtained by means of a Monte Carlo simulation-based fatigue analysis.

  10. Reversible pumped hydro - benefits and challenges

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Torbjoern K.; Walseth, Eve C.

    2010-07-01

    Full text: The Norwegian hydro power system is dominated with high head turbines, Pelton and Francis with high capacity in the reservoirs. Originally they were built for secure energy supply. In the system there are also reversible pump turbine (RPT) plants where in times with spare energy, made it possible to pump water from the lower reservoir to the higher. Again the idea was to secure energy supply, which meant pumping in early autumn to fill the reservoirs for winter. In the recent years, a more active use of the RPT plants has been actualized. The free market made price difference between night and day interesting, hence a more frequent pumping was desirable. In the coming years, new-renewable energy sources will utterly enhance a more active use of the RPT plants. More active use of the RPT plants means more frequent starts and stops, both in pumping and in turbine mode. There are a lot of challenges in adopting a new strategy for operating the machinery. More effective start equipment is required. The machinery will be exposed to more frequent dynamic loads; the turbines will be run at part- and full load. The existing RPT plants are connected to huge reservoirs. That means the RPTs are not only for short sighted power regulations, as many RPT-plants in Europe, but are also capable for a substantial energy production. In Norway, the nature is very suitable for RPT plants, both in connection with existing power plants, were reservoirs and conduits are already established, and standing alone with a minimum of energy production. RPTs are, as a design, a compromise between effective generating and stable as well as effective pumping. Stable pumping often results in very steep flow-speed characteristics when operating as a turbine. When dealing with hydraulic transients these characteristics cause a higher change in flow and torque leading to instability during start-up and possible off-design operation point. The instability slows down the synchronization

  11. Pump element for a tube pump

    DEFF Research Database (Denmark)

    2011-01-01

    The invention relates to a tube pump comprising a tube and a pump element inserted in the tube, where the pump element comprises a rod element and a first and a second non-return valve member positioned a distance apart on the rod element. The valve members are oriented in the same direction rela...... to a part of the tube. The invention further relates to a method for creating a flow of a fluid within an at least partly flexible tube by means of a pump element as mentioned above.......The invention relates to a tube pump comprising a tube and a pump element inserted in the tube, where the pump element comprises a rod element and a first and a second non-return valve member positioned a distance apart on the rod element. The valve members are oriented in the same direction...... portion acts to alternately close and open the valve members thereby generating a fluid flow through the tube. The invention further relates to a pump element comprising at least two non-return valve members connected by a rod element, and for insertion in an at least partly flexible tube in such tube...

  12. Thermal-hydraulic modeling and analysis of hydraulic system by pseudo-bond graph

    Institute of Scientific and Technical Information of China (English)

    胡均平; 李科军

    2015-01-01

    To increase the efficiency and reliability of the thermodynamics analysis of the hydraulic system, the method based on pseudo-bond graph is introduced. According to the working mechanism of hydraulic components, they can be separated into two categories: capacitive components and resistive components. Then, the thermal-hydraulic pseudo-bond graphs of capacitive C element and resistance R element were developed, based on the conservation of mass and energy. Subsequently, the connection rule for the pseudo-bond graph elements and the method to construct the complete thermal-hydraulic system model were proposed. On the basis of heat transfer analysis of a typical hydraulic circuit containing a piston pump, the lumped parameter mathematical model of the system was given. The good agreement between the simulation results and experimental data demonstrates the validity of the modeling method.

  13. Head pulsations in a centrifugal pump

    Science.gov (United States)

    Boiko, V. S.; Sotnyk, M. I.; Moskalenko, V. V.

    2017-08-01

    This article investigated the factors, which affect to the character of the head pulsations of a centrifugal pump. We investigated the dependence of the shape and depth of these pulsations from the operation mode of the pump. Was determined, that the head pulsations at the outlet of the impeller (pulsations on the blade passing frequency) cause head pulsations at the outlet of the pump, that have the same frequency, but differ in shape and depth. These pulsations depend on the design features of the flow-through part of the pump (from the ratio of hydraulic losses on the friction and losses on the vortex formation). A feature of the researches that were conducted is also the using of not only hydraulic but also electric modeling methods. It allows determining the values of the components of hydraulic losses.

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

    Science.gov (United States)

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

    2013-03-01

    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.

  15. Centrifugal pumps

    CERN Document Server

    Anderson, HH

    1981-01-01

    Centrifugal Pumps describes the whole range of the centrifugal pump (mixed flow and axial flow pumps are dealt with more briefly), with emphasis on the development of the boiler feed pump. Organized into 46 chapters, this book discusses the general hydrodynamic principles, performance, dimensions, type number, flow, and efficiency of centrifugal pumps. This text also explains the pumps performance; entry conditions and cavitation; speed and dimensions for a given duty; and losses. Some chapters further describe centrifugal pump mechanical design, installation, monitoring, and maintenance. The

  16. Quantifying the Efficiency Advantages of High Viscosity Index Hydraulic Fluids

    Institute of Scientific and Technical Information of China (English)

    Christian D. Neveu; Michael D. Zink; Alex Tsay

    2006-01-01

    By providing higher in- use viscosity at elevated operating temperatures, hydraulic fluids with high viscosity index improve the efficiency of the hydraulic system. For mobile hydraulic equipment this efficiency can be quantified as an increase in fuel economy. This paper reviews the research that demonstrates these efficiency advantages in gear, vane and piston pumps and presents a method for predicting the overall fuel economy for a fleet of hydraulic equipment in opquipment operator to easily improve the performance of the system and reduce fuel consumption.

  17. Influence of flow velocity circulation at guide vane outlet of axial-flow pump on hydraulic loss in outlet conduit%轴流泵装置导叶出口水流速度环量对出水流道水力损失的影响

    Institute of Scientific and Technical Information of China (English)

    梁金栋; 陆林广; 徐磊; 陈伟; 王刚

    2012-01-01

    为了定量研究大型泵装置导叶出口水流的速度环量对出水流道水力性能的影响,提出了泵装置导叶出口断面水流的速度环量定量表示方法和平均角速度的测量方法,分别采用数值计算和模型试验的方法研究了导叶出口水流的剩余环量对虹吸式出水流道和直管式出水流道水力损失的影响.结果表明:导叶出口水流的环量对出水流道水力损失的影响较为明显,存在使出水流道水力损失最小的最优环量,虹吸式和直管式出水流道的最优环量分别为0.972和1.308 m2/s;虹吸式出水流道和直管式出水流道最优环量时的水力损失计算值较零环量时的水力损失计算值分别小0.126和0.180 m.研究结果不仅有助于改进低扬程泵装置出水流道的优化水力设计,同时对改进轴流泵导叶的优化水力设计也有重要意义.%In order to study influence of the velocity circulation at the guide vane outlet on the hydraulic performance of outlet conduit for a large pump system quantitatively, the methods to calculate velocity circulation and to measure the average angular velocity for the flow at the guide vane outlet of the pump system were put forward, the influence of circulation on the hydraulic losses of both siphon and straight outlet conduit were studied numerically and experimentally. The results indicated that the hydraulic loss of the outlet conduit was obviously influenced by the circulation at the guide vane outlet. There was an optimum circulation for the hydraulic loss of the outlet conduit to be minimized, the optimum circulation for siphon and straight outlet conduit was 0.972 and 1.308 m2/s respectively. The hydraulic losses calculated of the siphon and straight conduit under the condition of the optimal circulation were respectively lower 0.126 and 0.180 m than those under the condition of zero circulation. This study above could be helpful to optimal hydraulic design both for outlet

  18. Aircraft Hydraulic Systems Dynamic Analysis

    Science.gov (United States)

    1978-10-01

    4400 PSIG OUTLET PRESSURE ~’f UM5 S1 l .( FIF ~0RV lR 1 .I. AP (c R (V) IFWM) APPROX C ASE !VPý :iI S ReUN N•;MRF.. r p kN i t, isI A! f IN, I:E • ’l...and 1F.GI pump modelo were assumed from data supplied by CECO. 165 _ -- --- - SECTION V HYDRAULIC MOTOR MODEL DEVELOPMENT AND VERIFICATION A fixed...3 70 P.,0 601 ~4 M24.0 3 1p ’, 4 r I 1 1 ISIS 2411 APPENDIX E (CONT.) HSFR TECHNICAL MANUAL (AFAPL-TR-76-43, VOL. IV) 4.15 VANE PU`MP SUBROUTINE 4.15A

  19. On the Hydraulics of Flowing Horizontal Wells

    Science.gov (United States)

    Bian, A.; Zhan, H.

    2003-12-01

    A flowing horizontal well is a special type of horizontal well that does not have pumping/injecting facility. The discharge rate of a flowing horizontal well is controlled by the hydraulic gradient between the aquifer and the well and it generally varies with time if the hydraulic head of the aquifer is transient. This type of well has been used in landslide control, mining dewatering, water table control, underground water transportation through a horizontal tunnel, agricultural water drainage, and other applications. Flowing horizontal wells have quite different hydrodynamic characteristics from horizontal wells with fixed pumping or injecting rates because their discharge rates are functions of the aquifer hydraulic heads (Zhan et al, 2001; Zhan and Zlotnik, 2002). Hydraulics of flowing horizontal wells have rarely been studied although the hydraulics of flowing vertical wells have been extensively investigated before. The purpose of this paper is to obtain analytical solutions of groundwater flow to a flowing horizontal-well in a confined aquifer, in a water table aquifer without precipitation, and in a water table aquifer with precipitation. The functions of the flowing horizontal well discharge rates versus time will be obtained under above mentioned different aquifer conditions. The relationships of the aquifer hydraulic heads versus the discharge rates of the well will be investigated. The rate of water table decline due to the dewatering of the well will also be computed, and this solution is particularly useful for landslide control and mining dewatering. The theoretical solutions will be compared with results of experiments that will be conducted in the hydrological laboratory at Texas A&M University. Reference: Zhan, H., Wang, L.V., and Park, E, On the horizontal well pumping tests in the anisotropic confined aquifers, J. hydrol., 252, 37-50, 2001. Zhan, H., and Zlotnik, V. A., Groundwater flow to a horizontal or slanted well in an unconfined aquifer

  20. Mathematic Modeling of Complex Hydraulic Machinery Systems When Evaluating Reliability Using Graph Theory

    Science.gov (United States)

    Zemenkova, M. Yu; Shipovalov, A. N.; Zemenkov, Yu D.

    2016-04-01

    The main technological equipment of pipeline transport of hydrocarbons are hydraulic machines. During transportation of oil mainly used of centrifugal pumps, designed to work in the “pumping station-pipeline” system. Composition of a standard pumping station consists of several pumps, complex hydraulic piping. The authors have developed a set of models and algorithms for calculating system reliability of pumps. It is based on the theory of reliability. As an example, considered one of the estimation methods with the application of graph theory.

  1. A Hydraulic Motor-Alternator System for Ocean-Submersible Vehicles

    Science.gov (United States)

    Aintablian, Harry O.; Valdez, Thomas I.; Jones, Jack A.

    2012-01-01

    An ocean-submersible vehicle has been developed at JPL that moves back and forth between sea level and a depth of a few hundred meters. A liquid volumetric change at a pressure of 70 bars is created by means of thermal phase change. During vehicle ascent, the phase-change material (PCM) is melted by the circulation of warm water and thus pressure is increased. During vehicle descent, the PCM is cooled resulting in reduced pressure. This pressure change is used to generate electric power by means of a hydraulic pump that drives a permanent magnet (PM) alternator. The output energy of the alternator is stored in a rechargeable battery that powers an on-board computer, instrumentation and other peripherals.The focus of this paper is the performance evaluation of a specific hydraulic motor-alternator system. Experimental and theoretical efficiency data of the hydraulic motor and the alternator are presented. The results are used to evaluate the optimization of the hydraulic motor-alternator system. The integrated submersible vehicle was successfully operated in the Pacific Ocean near Hawaii. A brief overview of the actual test results is presented.

  2. Measurement and evaluation of static characteristics of rotary hydraulic motor

    Directory of Open Access Journals (Sweden)

    Hružík Lumír

    2014-03-01

    Full Text Available The paper describes experimental equipment for measurement of static characteristics of rotary hydraulic motor. It is possible to measure flow, pressure, temperature, speed and torque by means of this equipment. It deals with measurement of static characteristics of a gear rotary hydraulic motor. Mineral oil is used as hydraulic liquid in this case. Flow, torque and speed characteristics are evaluated from measured parameters. Measured mechanical-hydraulic, flow and total efficiencies of the rotary hydraulic motor are adduced in the paper. It is possible to diagnose technical conditions of the hydraulic motor (eventually to recommend its exchange from the experimental measurements.

  3. On-Shore Central Hydraulic Power Generation for Wind and Tidal Energy

    Science.gov (United States)

    Jones, Jack A.; Bruce, Allan; Lim, Steven; Murray, Luke; Armstrong, Richard; Kimbrall, Richard; Cook-Chenault, Kimberly; DeGennaro, Sean

    2012-01-01

    Tidal energy, offshore wind energy, and onshore wind energy can be converted to electricity at a central ground location by means of converting their respective energies into high-pressure hydraulic flows that are transmitted to a system of generators by high-pressure pipelines. The high-pressure flows are then efficiently converted to electricity by a central power plant, and the low-pressure outlet flow is returned. The Department of Energy (DOE) is presently supporting a project led by Sunlight Photonics to demonstrate a 15 kW tidal hydraulic power generation system in the laboratory and possibly later submerged in the ocean. All gears and submerged electronics are completely eliminated. A second portion of this DOE project involves sizing and costing a 15 MW tidal energy system for a commercial tidal energy plant. For this task, Atlantis Resources Corporation s 18-m diameter demonstrated tidal blades are rated to operate in a nominal 2.6 m/sec tidal flow to produce approximately one MW per set of tidal blades. Fifteen units would be submerged in a deep tidal area, such as in Maine s Western Passage. All would be connected to a high-pressure (20 MPa, 2900 psi) line that is 35 cm ID. The high-pressure HEPG fluid flow is transported 500-m to on-shore hydraulic generators. HEPG is an environmentally-friendly, biodegradable, watermiscible fluid. Hydraulic adaptations to ORPC s cross-flow turbines are also discussed. For 15 MW of wind energy that is onshore or offshore, a gearless, high efficiency, radial piston pump can replace each set of top-mounted gear-generators. The fluid is then pumped to a central, easily serviceable generator location. Total hydraulic/electrical efficiency is 0.81 at full rated wind or tidal velocities and increases to 0.86 at 1/3 rated velocities.

  4. On-Shore Central Hydraulic Power Generation for Wind and Tidal Energy

    Science.gov (United States)

    Jones, Jack A.; Bruce, Allan; Lim, Steven; Murray, Luke; Armstrong, Richard; Kimbrall, Richard; Cook-Chenault, Kimberly; DeGennaro, Sean

    2012-01-01

    Tidal energy, offshore wind energy, and onshore wind energy can be converted to electricity at a central ground location by means of converting their respective energies into high-pressure hydraulic flows that are transmitted to a system of generators by high-pressure pipelines. The high-pressure flows are then efficiently converted to electricity by a central power plant, and the low-pressure outlet flow is returned. The Department of Energy (DOE) is presently supporting a project led by Sunlight Photonics to demonstrate a 15 kW tidal hydraulic power generation system in the laboratory and possibly later submerged in the ocean. All gears and submerged electronics are completely eliminated. A second portion of this DOE project involves sizing and costing a 15 MW tidal energy system for a commercial tidal energy plant. For this task, Atlantis Resources Corporation s 18-m diameter demonstrated tidal blades are rated to operate in a nominal 2.6 m/sec tidal flow to produce approximately one MW per set of tidal blades. Fifteen units would be submerged in a deep tidal area, such as in Maine s Western Passage. All would be connected to a high-pressure (20 MPa, 2900 psi) line that is 35 cm ID. The high-pressure HEPG fluid flow is transported 500-m to on-shore hydraulic generators. HEPG is an environmentally-friendly, biodegradable, watermiscible fluid. Hydraulic adaptations to ORPC s cross-flow turbines are also discussed. For 15 MW of wind energy that is onshore or offshore, a gearless, high efficiency, radial piston pump can replace each set of top-mounted gear-generators. The fluid is then pumped to a central, easily serviceable generator location. Total hydraulic/electrical efficiency is 0.81 at full rated wind or tidal velocities and increases to 0.86 at 1/3 rated velocities.

  5. Magnetocaloric pump

    Science.gov (United States)

    Brown, G. V.

    1973-01-01

    Very cold liquids and gases such as helium, neon, and nitrogen can be pumped by using magnetocaloric effect. Adiabatic magnetization and demagnetization are used to alternately heat and cool slug of pumped fluid contained in closed chamber.

  6. Analysis of an controller design for an electro-hydraulic servo pressure regulator

    DEFF Research Database (Denmark)

    Pedersen, Henrik C.; Andersen, Torben Ole; Madsen, A. M.;

    2009-01-01

    of the existing hydraulic components there are, however, still a need for being able to generate a hydraulic pilot pressure, as e.g. almost all open-circuit pumps are hydraulically controlled. The focus of the current paper is therefore on the analysis and controller design an electro-hydraulic servo pressure...... regulator, which generates a hydraulic LS-pressure based on an electrical reference, hereby synergistically integrating knowledge from all parts of the mechatronics area. The servo pressure regulator is used to generate the LS-signal for a variable displacement pump, and the paper rst presents...... to generate a controlled leakage  ow that aids in stabilising the system. The robustness of the system is then discussed in relation to dierent pilot line volumes and pump dynamics. Finally experimental results are presented, where the performance is compared to that of a similar hydraulic reference system...

  7. Heat pumps

    CERN Document Server

    Macmichael, DBA

    1988-01-01

    A fully revised and extended account of the design, manufacture and use of heat pumps in both industrial and domestic applications. Topics covered include a detailed description of the various heat pump cycles, the components of a heat pump system - drive, compressor, heat exchangers etc., and the more practical considerations to be taken into account in their selection.

  8. Wind tunnel experiments to prove a hydraulic passive rotor speed control concept for variable speed wind turbines (poster)

    NARCIS (Netherlands)

    Diepeveen, N.F.B.; Jarquin Laguna, A.

    2012-01-01

    As alternative to geared and direct drive solutions, fluid power drive trains are being developed by several institutions around the world. The common configuration is where the wind turbine rotor is coupled to a hydraulic pump. The pump is connected through a high pressure line to a hydraulic motor

  9. Heat pumps

    CERN Document Server

    Brodowicz, Kazimierz; Wyszynski, M L; Wyszynski

    2013-01-01

    Heat pumps and related technology are in widespread use in industrial processes and installations. This book presents a unified, comprehensive and systematic treatment of the design and operation of both compression and sorption heat pumps. Heat pump thermodynamics, the choice of working fluid and the characteristics of low temperature heat sources and their application to heat pumps are covered in detail.Economic aspects are discussed and the extensive use of the exergy concept in evaluating performance of heat pumps is a unique feature of the book. The thermodynamic and chemical properties o

  10. HYDRAULICS, LOUISA COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulic data include spatial datasets and data tables necessary for documenting the hydraulic analysis for estimating flood stages for a flood insurance study. It...

  11. Hydraulic Hybrid Vehicles

    Science.gov (United States)

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

  12. Plug & Play Control of Hydraulic Networks

    DEFF Research Database (Denmark)

    Jensen, Tom Nørgaard

    2012-01-01

    Process Control research program, which the work presented here is a part of. An industrial case study involving a large-scale hydraulic network with non-linear dynamics is studied. The hydraulic network underlies a district heating system, which provides heating water to a number of end-users in a city...... structure has the additional benefit that structural changes such as the addition or removal of end-users are easily implementable. In this work, the problem of controlling the pressure drop at the end-users to a constant reference value is considered. This is done by the use of pumps located both...... are considered. Some of the work considers control actions which are constrained to non-negative values only. This is due to the fact that the actuators in this type of system typically consist of centrifugal pumps which are only able to deliver non-negative actuation. Other parts of the work consider control...

  13. Technical note: Analytical drawdown solution for steady-state pumping tests in two-dimensional isotropic heterogeneous aquifers

    Science.gov (United States)

    Zech, Alraune; Attinger, Sabine

    2016-05-01

    A new method is presented which allows interpreting steady-state pumping tests in heterogeneous isotropic transmissivity fields. In contrast to mean uniform flow, pumping test drawdowns in heterogeneous media cannot be described by a single effective or equivalent value of hydraulic transmissivity. An effective description of transmissivity is required, being a function of the radial distance to the well and including the parameters of log-transmissivity: mean, variance, and correlation length. Such a model is provided by the upscaling procedure radial coarse graining, which describes the transition of near-well to far-field transmissivity effectively. Based on this approach, an analytical solution for a steady-state pumping test drawdown is deduced. The so-called effective well flow solution is derived for two cases: the ensemble mean of pumping tests and the drawdown within an individual heterogeneous transmissivity field. The analytical form of the solution allows inversely estimating the parameters of aquifer heterogeneity. For comparison with the effective well flow solution, virtual pumping tests are performed and analysed for both cases, the ensemble mean drawdown and pumping tests at individual transmissivity fields. Interpretation of ensemble mean drawdowns showed proof of the upscaling method. The effective well flow solution reproduces the drawdown for two-dimensional pumping tests in heterogeneous media in contrast to Thiem's solution for homogeneous media. Multiple pumping tests conducted at different locations within an individual transmissivity field are analysed, making use of the effective well flow solution to show that all statistical parameters of aquifer heterogeneity can be inferred under field conditions. Thus, the presented method is a promising tool with which to estimate parameters of aquifer heterogeneity, in particular variance and horizontal correlation length of log-transmissivity fields from steady-state pumping test measurements.

  14. Transient two-phase performance of LOFT reactor coolant pumps

    Energy Technology Data Exchange (ETDEWEB)

    Chen, T.H.; Modro, S.M.

    1983-01-01

    Performance characteristics of Loss-of-Fluid Test (LOFT) reactor coolant pumps under transient two-phase flow conditions were obtained based on the analysis of two large and small break loss-of-coolant experiments conducted at the LOFT facility. Emphasis is placed on the evaluation of the transient two-phase flow effects on the LOFT reactor coolant pump performance during the first quadrant operation. The measured pump characteristics are presented as functions of pump void fraction which was determined based on the measured density. The calculated pump characteristics such as pump head, torque (or hydraulic torque), and efficiency are also determined as functions of pump void fractions. The importance of accurate modeling of the reactor coolant pump performance under two-phase conditions is addressed. The analytical pump model, currently used in most reactor analysis codes to predict transient two-phase pump behavior, is assessed.

  15. Dynamic Analysis & Characterization of Conventional Hydraulic Power Supply Units

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Liedhegener, Michael; Bech, Michael Møller

    2016-01-01

    Hydraulic power units operated as constant supply pres-sure systems remain to be widely used in the industry, to supply valve controlled hydraulic drives etc., where the hydraulic power units are constituted by variable pumps with mechanical outlet pressure control, driven by induction motors...... and drives will reduce the flow-to-pressure gain of the supply system, and hence increase the time constant of the sup-ply pressure dynamics. A consequence of this may be large vari-ations in the supply pressure, hence large variations in the pump shaft torque, and thereby the induction motor load torque......, with possible excitation of the induction motor dynamics as a result. In such cases, the coupled dynamics of the pressure controlled pump and induction motor may influence the supply pressure sig-nificantly, possibly affecting the dynamics of the supplied drives, especially in cases where pilot operated valves...

  16. RESEARCH OF THE DYNAMIC CHARACTERISTICS ON A NEW HYDRAULIC SYSTEM OF ELECTRO-HYDRAULIC HAMMER

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new typed hydraulic system of electro-hydraulic hammer is researched and developed.By means of power bond graphs the modeling and simulation to the dynamic characteristics of the new hydraulic system are performed. The experimental research which is emphasized on the blowing stroke is also performed. It is proved from the result of simulation and experiment that this new hydraulic system possesses such advantages as simplification of structure,flexibleness of operation and reliability of working. Especially it possesses better dynamic characteristics.

  17. Numerical study identifying the factors causing the significant underestimation of the specific discharge estimated using the modified integral pumping test method in a laboratory experiment.

    Science.gov (United States)

    Sun, Kerang

    2015-09-01

    A three-dimensional finite element model is constructed to simulate the experimental conditions presented in a paper published in this journal [Goltz et al., 2009. Validation of two innovative methods to measure contaminant mass flux in groundwater. Journal of Contaminant Hydrology 106 (2009) 51-61] where the modified integral pumping test (MIPT) method was found to significantly underestimate the specific discharge in an artificial aquifer. The numerical model closely replicates the experimental configuration with explicit representation of the pumping well column and skin, allowing for the model to simulate the wellbore flow in the pumping well as an integral part of the porous media flow in the aquifer using the equivalent hydraulic conductivity approach. The equivalent hydraulic conductivity is used to account for head losses due to friction within the wellbore of the pumping well. Applying the MIPT method on the model simulated piezometric heads resulted in a specific discharge that underestimates the true specific discharge in the experimental aquifer by 18.8%, compared with the 57% underestimation of mass flux by the experiment reported by Goltz et al. (2009). Alternative simulation shows that the numerical model is capable of approximately replicating the experiment results when the equivalent hydraulic conductivity is reduced by an order of magnitude, suggesting that the accuracy of the MIPT estimation could be improved by expanding the physical meaning of the equivalent hydraulic conductivity to account for other factors such as orifice losses in addition to frictional losses within the wellbore. Numerical experiments also show that when applying the MIPT method to estimate hydraulic parameters, use of depth-integrated piezometric head instead of the head near the pump intake can reduce the estimation error resulting from well losses, but not the error associated with the well not being fully screened.

  18. Hydraulic modelling of drinking water treatment plant operations

    OpenAIRE

    L. C. Rietveld; Borger, K.J.; Van Schagen, K.M.; Mesman, G.A.M.; G. I. M. Worm

    2008-01-01

    For a drinking water treatment plant simulation, water quality models, a hydraulic model, a process-control model, an object model, data management, training and decision-support features and a graphic user interface have been integrated. The integration of a hydraulic model in the simulator is necessary to correctly determine the division of flows over the plant's lanes and, thus, the flow through the individual treatment units, based on valve positions and pump speeds. The flow through a un...

  19. Hydraulic Conductivity Estimate via Tracer Test and Ensemble Kalman Filter Data Assimilation: Theoretical and Numerical Fundamentals

    Science.gov (United States)

    Crestani, E.; Camporese, M.; Salandin, P.

    2011-12-01

    Hydraulic properties of natural aquifers, such as porosity, hydraulic conductivity, and storativity, exhibit an erratic spatial variability at different scales that is difficult to recognize without expensive in situ sampling campaigns, laboratory analyses, and, when available, spatially distributed pumping tests. Nevertheless, the importance of the heterogeneous structure of natural formations on solute transport is well recognized, being the non-Fickian evolution of contaminant plumes and the relevant dispersive phenomena controlled by the variability of the hydraulic conductivity K at the local scale. Tracer test analyses have been widely adopted to identify the complex distribution of in situ hydraulic properties. In particular, the use of geophysical methods like the borehole Electrical Resistivity Tomography (ERT) have been in rapid increase, due to their potential to accurately describe the spatio-temporal evolution of the injected solute. Under the assumptions that the solute spreads as a passive tracer and with high values of the Peclet number, the plume evolution is controlled by the porosity and the spatial distribution of hydraulic conductivity. Combining the Lagrangian formulation of transport and the ensemble Kalman filter (EnKF) data assimilation technique, the purpose of this study is to infer the spatial distribution of K at the local scale from a sequence of time-lapse concentration imaging. The capabilities of the proposed approach are investigated simulating various assimilation experiments via synthetic tracer tests in a three-dimensional finite domain reproducing a heterogeneous aquifer. In a first scenario, all the available concentration measurements are assimilated and the entire hydraulic conductivity field is updated, while in the remaining scenarios the K values are updated only in a limited number of nodes by assimilating the concentrations in these same nodes, the hydraulic conductivity in the rest of the domain being the result of a

  20. Research on the Performance of Hydraulic Excavator with Pump and Valve Combined Separate Meter In and Meter Out Circuits%泵阀复合进出口独立控制液压挖掘机特性研究

    Institute of Scientific and Technical Information of China (English)

    董致新; 黄伟男; 葛磊; 权龙; 黄家海; 杨敬

    2016-01-01

    Conventional hydraulic actuator is controlled by mechanically connected orifices valve. This controllability of this method is poor and the energy consumption is huge especially under the over-running condition. So a novel system configuration is presented, in which boom cylinder, stick cylinder and swing motor are controlled with separate meter in and meter out technology, bucket cylinder and travel motors are controlled with conventional valves. A virtual prototype is established,which consists of the hydraulic excavator mechanical structure with multi-body dynamics and electro-hydraulic system. The dynamic, static performances as well as the energy consumption characteristics of the boom, arm and swing actuators are investigated under the condition of load sensing hydraulic system and the proposed system. After that, the physical prototype based on the proposed configuration system is established and its performance is tested. The experimental results show that the accuracy of the virtual prototype is validated, the proposed configuration system can significantly decreases the pressure losses through the valve and improve the energy efficiency of the machine; the pressure shocks within hydraulic actuators is decreased as well, thus the stationarity of the whole machine is improved accordingly.%传统四边联动阀控制液压执行器可控性差、在超越负载工况能耗大。为改进这些不足,提出动臂、斗杆液压缸和回转液压马达采用泵阀复合、流量压力匹配进出口独立控制、铲斗液压缸与行走液压马达采用原有四边联动阀的液压挖掘机整机方案。建立液压挖掘机机械结构多刚体动力学与电液系统联合的数字样机,利用该样机分别对采用负载敏感系统和新回路系统控制的动臂、斗杆和回转马达三个执行机构动静态性能和能耗特性进行研究。进一步构建基于上述原理的试验测试样机,试验结果表明所建立数字样机

  1. FOREWORD: 26th IAHR Symposium on Hydraulic Machinery and Systems

    Science.gov (United States)

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

    2012-11-01

    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

  2. Impulse Pump

    Science.gov (United States)

    2016-06-17

    to drive the impulse motion. [0008] Other methods to store energy can be used to drive an impulse or impact device. Pneumatic and hydraulic ...Additionally, the present invention combines components known in the art, including an electric motor, a flywheel, a planetary gear clutch, hydraulic caliper...of the pusher shaft 22 with the associated movement of the cam race-way 74. Rotation of the pusher shaft 22 causes a cam follower arm 80 to be

  3. Pump control system for windmills

    Science.gov (United States)

    Avery, Don E.

    1983-01-01

    A windmill control system having lever means, for varying length of stroke of the pump piston, and a control means, responsive to the velocity of the wind to operate the lever means to vary the length of stroke and hence the effective displacement of the pump in accordance with available wind energy, with the control means having a sensing member separate from the windmill disposed in the wind and displaceable thereby in accordance with wind velocity.

  4. System Topology Optimization - An Approach to System Design of Electro-Hydraulic-Mechanical Systems

    DEFF Research Database (Denmark)

    Andersen, T. O.; Hansen, M. R.; Conrad, Finn

    2003-01-01

    design the procedure attempts to find the optimal topology and the related parameters. The topology considerations comprise the type of hydraulic pump, the employment of knee linkages or not as well as the type of hydraulic actuators. The design variables also include the signals to the proportional......The current paper presents an approach to system design of combined electro-hydraulic-mechanical systems. The approach is based on the concurrent handling of the topology as well as the design parameters of the mechanical, hydraulic and controller sub- systems, respectively. Based on an initial...... valve in a number of predefined load cases as well as the hydraulic and mechanical parameters....

  5. Resonance wave pumping: wave mass transport pumping

    Science.gov (United States)

    Carmigniani, Remi; Violeau, Damien; Gharib, Morteza

    2016-11-01

    It has been previously reported that pinching at intrinsic resonance frequencies a valveless pump (or Liebau pump) results in a strong pulsating flow. A free-surface version of the Liebau pump is presented. The experiment consists of a closed tank with a submerged plate separating the water into a free-surface and a recirculation section connected through two openings at each end of the tank. A paddle is placed at an off-centre position at the free-surface and controlled in a heaving motion with different frequencies and amplitudes. Near certain frequencies identified as resonance frequencies through a linear potential theory analysis, the system behaves like a pump. Particle Image Velocimetry (PIV) is performed in the near free surface region and compared with simulations using Volume of Fluid (VOF) method. The mean eulerian mass flux field (ρ) is extracted. It is observed that the flow is located in the vicinity of the surface layer suggesting Stokes Drift (or Wave Mass Transport) is the source of the pumping. A model is developped to extend the linear potential theory to the second order to take into account these observations. The authors would like to acknowledge the Gordon and Betty Moore Foundation for their generous support.

  6. 轴流泵水力模型内部流场数值模拟%Numerical simulation of internal flow field in hydraulic model of axial-flow pump

    Institute of Scientific and Technical Information of China (English)

    齐学义; 汪玮华; 郝连松

    2012-01-01

    Based on the Reynolds time-averaged Navier-Stokes equations with turbulence mode, by using SIMPLEC algorithm to make pressure-velocity coupling, and by using the implicit different format with second-order accuracy, the stationary 3-D turbulent flow in axial-flow pump was numerically simulated and the velocity vectors, static pressure contours, and other flow informations were obtained. The simulation result showed that the flow field distribution and flow form were better in general in design condition, but a local low pressure area occurred at the inlet of impeller blade back near the wheel rim and the load on the outer wall of guide vane was large, indicating that it would be necessary to improve the axial-flow pump model and pump performance.%基于Reynolds时均N-S方程,采用标准k-ε湍流模型,压力、速度耦合使用SIMPLEC算法,离散采用具有二阶精度的隐式格式差分,对轴流泵过流部件内部流场进行三维定常湍流数值模拟,得到泵内流动的速度和压力矢量分布图,以及其他一些流动的信息.数值模拟结果表明,设计工况下的流场分布和流态总体较好,但叶轮叶片背面进口靠近轮缘处出现局部低压,导叶外壁区域负荷大,说明该轴流泵水力模型还有进一步改进和对其性能进一步提高的必要.

  7. Prediction of S-shaped characteristics in reversible pump-turbines using different numerical approaches

    Science.gov (United States)

    Lenarcic, M.; Bauer, Ch.; Giese, M.; Jung, A.

    2016-11-01

    The prediction of characteristics and flow phenomena in reversible pump-turbines becomes increasingly important, since operations under off-design conditions are required to respond to frequency fluctuations within the electrical grid as fast as possible. Fulfilling the requirements of a stable and reliable operation under continuously expanding operating ranges challenges the hydraulic design and requires ambitious developments. Beyond that, precise estimations of occurring flow phenomena combined with a detailed understanding of their causes and mechanisms are essential. This study aims at predicting the S-shaped characteristics of two reversible pump-turbines by using different numerical approaches. Therefore, measurements at a constant wicket-gate opening of Δγ = 10° were done. Based on these experimental data, unsteady flow simulations are performed under steady and transient operating conditions respectively: Starting from the best efficiency point in generating mode, through the runaway, along the S-curve, down to operation in reverse pump mode. The hydraulic machines are spatially discretized in model size with a near-wall refinement of y + mean ≤ 5 and y + mean ≥ 30. The application of two different solvers discloses deviations in underlying methods. The turbulence modeling is basically executed by the k-ω-SST and the standard k-ɛ model. Focusing on higher order numerics, the Explicit Algebraic Reynolds Stress Model (EARSM) is selected in the commercial code and extended with an approach for curvature correction (EARSM- CC). In the open-source software, the four-equation v2-f model assumes the role of higher order numerics. The temporal discretization errors are observed using three different time-step sizes. As a supplement, experimental data obtained from the HydroDyna pump-turbine are used as additional validation, providing integral quantities and local pressure distributions at an operating point set on the S-curve. To sum this work up, a

  8. Direct writing of micro/nano-scale patterns by means of particle lens arrays scanned by a focused diode pumped Nd:YVO4 laser

    Science.gov (United States)

    Pena, Ana; Wang, Zengbo; Whitehead, David; Li, Lin

    2010-11-01

    A practical approach to a well-known technique of laser micro/nano-patterning by optical near fields is presented. It is based on surface patterning by scanning a Gaussian laser beam through a self-assembled monolayer of silica micro-spheres on a single-crystalline silicon (Si) substrate. So far, the outcome of this kind of near-field patterning has been related to the simultaneous, parallel surface-structuring of large areas either by top hat or Gaussian laser intensity distributions. We attempt to explore the possibility of using the same technique in order to produce single, direct writing of features. This could be of advantage for applications in which only some areas need to be patterned (i.e. local area selective patterning) or single lines are required (e.g. a particular micro/nano-fluidic channel). A diode pumped Nd:YVO4 laser system (wavelength of 532 nm, pulse duration of 8 ns, repetition rate of 30 kHz) with a computer-controlled 3 axis galvanometer beam scanner was employed to write user-defined patterns through the particle lens array on the Si substrate. After laser irradiation, the obtained patterns which are in the micro-scale were composed of sub-micro/micro-holes or bumps. The micro-pattern resolution depends on the dimension of both the micro-sphere’s diameter and the beam’s spot size. The developed technique could potentially be employed to fabricate photonic crystal structures mimicking nature’s butterfly wings and anti-reflective “moth eye” arrays for photovoltaic cells.

  9. Ferroelectric Pump

    Science.gov (United States)

    Jalink, Antony, Jr. (Inventor); Hellbaum, Richard F. (Inventor); Rohrbach, Wayne W. (Inventor)

    2000-01-01

    A ferroelectric pump has one or more variable volume pumping chambers internal to a housing. Each chamber has at least one wall comprising a dome shaped internally prestressed ferroelectric actuator having a curvature and a dome height that varies with an electric voltage applied between an inside and outside surface of the actuator. A pumped medium flows into and out of each pumping chamber in response to displacement of the ferroelectric actuator. The ferroelectric actuator is mounted within each wall and isolates each ferroelectric actuator from the pumped medium, supplies a path for voltage to be applied to each ferroelectric actuator, and provides for positive containment of each ferroelectric actuator while allowing displacement of the entirety of each ferroelectric actuator in response to the applied voltage.

  10. A straight path centrifugal blood pump concept in the Capiox centrifugal pump.

    Science.gov (United States)

    Kijima, T; Oshiyama, H; Horiuchi, K; Nogawa, A; Hamasaki, H; Amano, N; Nojiri, C; Fukasawa, H; Akutsu, T

    1993-07-01

    This article describes comparative studies of a newly developed "straight path" centrifugal pump (Capiox centrifugal pump) targeted for open-heart surgery and circulatory support. A unique straight path design of the rotor was very effective in reducing the pump's rotational speed and prime volume. This pump was evaluated for hydraulics, hemolysis, depriming characteristics, cavitation, and heat generation. Two commercially available centrifugal pumps, the Biomedicus cone-type pump and the Sarns 3M impeller-type pump, were used as controls. The new pump required the lowest pump speed to produce the same flow rates under the same pressure loads and demonstrated the lowest hemolysis and the lowest temperature rise with the outlet clamped. The air volume required to deprime the new pump was one-third to one-half that for the other pumps, and no sign of cavitation was observed even if a small amount of air was introduced to the pump inlet under a negative pressure of 200 mm Hg.

  11. Oscillatory Flow Testing in a Sandbox - Towards Oscillatory Hydraulic Tomography

    Science.gov (United States)

    Zhou, Y.; Lim, D.; Cupola, F.; Cardiff, M. A.

    2014-12-01

    Detailed knowledge of subsurface hydraulic properties is important for predicting groundwater flow and contaminant transport. The spatial variation of hydraulic properties in the shallow subsurface has been extensively studied in the past two decades. A recent approach to characterize subsurface properties is hydraulic tomography, in which pressure data from multiple constant-rate pumping tests is inverted using a numerical model. Many laboratory sandbox studies have explored the performance of hydraulic tomography under different controlled conditions and shown that detailed heterogeneity information can be extracted (Liu et al., 2002, Illman et al., 2007, 2008, 2010a, 2010b, Liu et al., 2007, 2008, Xiang et al., 2009, Yin and Illman, 2009, Liu and Kitanidis, 2011, Berg and Illman, 2011a). Recently, Cardiff et al. (2013) proposed a modified approach of Oscillatory Hydraulic Tomography (OHT) - in which periodic pumping signals of different frequencies are used for aquifer stimulation - to characterize aquifer properties. The potential advantages of OHT over traditional hydraulic tomography include: 1) no net injection or extraction of water; 2) little movement of existing contamination; 3) minimal impact of model boundary conditions; and 4) robust extraction of oscillatory signals from noisy data. To evaluate the premise of OHT, we built a highly-instrumented 2-D laboratory sandbox and record pressure responses to periodic pumping tests. In our setup, the laboratory sandbox is filled with sand of known hydraulic properties, and we measure aquifer responses at a variety of testing frequencies. The signals recorded are processed using Fourier-domain analysis, and compared against expected results under linear (Darcian) theory. The responses are analyzed using analytical and numerical models, which provide key insights as to: 1) how "effective" hydraulic properties estimated using homogeneous models are associated with aquifer heterogeneity; and 2) how OHT is able to

  12. LVP Modeling and Dynamic Characteristics Prediction of A Hydraulic Power Unit in Deep-Sea

    Institute of Scientific and Technical Information of China (English)

    CAO Xue-peng; YE Min; DENG Bin; ZHANG Cui-hong; YU Zu-ying

    2013-01-01

    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.

  13. Penis Pump

    Science.gov (United States)

    ... claim that they can be used to increase penis size, but there's no evidence that they work for ... circumstances, using a penis pump might help your penis maintain its natural size and shape after prostate surgery or if you ...

  14. Trends in the development of fluid-operated heat transfer devices for refrigerant feed pumps and heat pumps using non-azeotropic binary-fluid refrigerants with special regard to the problem of CFCs. Entwicklungstendenzen fluessigkeitsbeaufschlagter Waermeuebertrager fuer Kaelte- und Waermepumpenanlagen mit nichtazeotropen Zweistoffkaeltemitteln unter Beruecksichtigung der FCKW-Problematik

    Energy Technology Data Exchange (ETDEWEB)

    Goebel, F.

    1991-06-12

    In the construction of binary-fluid refrigerant heat transfer devices as evaporators and condensers in heat pumps for the cooling of waste heat flows, the hydraulic diametre of the media flows is decisive. By means of the flow against refrigerant-carrying tubes, heat transfer systems can be assigned to different categories. The heat transfer in a heat exchanger is determined by quantities such as water speed and flow conditions in refrigerant-carrying tubes. (VT)

  15. Analysis and control of flows in pressurized hydraulic networks

    NARCIS (Netherlands)

    Gupta, R.K.

    2006-01-01

    Analysis, design and flow control problems in pressurized hydraulic networks such as water transmission and distribution systems consisting of pipes and other appurtenant components such as reservoirs, pumps, valves and surge devices are dealt with from the prospective of network synthesis aiming at

  16. Analysis and control of flows in pressurized hydraulic networks

    NARCIS (Netherlands)

    Gupta, R.K.

    2006-01-01

    Analysis, design and flow control problems in pressurized hydraulic networks such as water transmission and distribution systems consisting of pipes and other appurtenant components such as reservoirs, pumps, valves and surge devices are dealt with from the prospective of network synthesis aiming at

  17. Review and prospect of research on hydraulic pulsation attenuator

    Science.gov (United States)

    Shan, Chang-ji; Zhao, Qi-jun; Dai, Ting-ting; Bian, Yi-duo; Cai, Yan

    2017-09-01

    The pressure pulsation attenuator is able to decrease the fluid fluctuation of the hydraulic pump effectively, so it is widely used in construction machinery. This paper reviews the history and progresses of the research on the pressure pulsation attenuator in China and overseas, summarizes its two types: H-type rigid structure and built-in flexible material, meanwhile, discusses its future research area.

  18. Vibration of hydraulic machinery

    CERN Document Server

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

    2013-01-01

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

  19. Handbook of hydraulic fluid technology

    CERN Document Server

    Totten, George E

    2011-01-01

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

  20. Hydraulic conductivities of fractures and matrix in Slovenian carbonate aquifers

    Directory of Open Access Journals (Sweden)

    Timotej Verbovšek

    2008-12-01

    Full Text Available Hydraulic conductivities and specific storage coefficients of fractures and matrix in Slovenian carbonate aquifers were determined by Barker’s method for pumping test analysis, based on fractional flow dimension. Values are presented for limestones and mainly for dolomites, and additionally for separate aquifers, divided by age andlithology in several groups. Data was obtained from hydrogeological reports for 397 water wells, and among these, 79 pumping tests were reinterpreted. Hydraulic conductivities of fractures are higher than the hydraulic conductivities of matrix, and the differences are highly statistically significant. Likewise, differences are significant for specific storage, and the values of these coefficients are higher in the matrix. Values of all coefficients vary in separate aquifers, and the differences can be explained by diagenetic effects, crystal size, degree of fracturing, andcarbonate purity. Comparison of the methods, used in the reports, and the Barker’s method (being more suitable for karstic and fractured aquifers, shows that the latter fits real data better.

  1. Periodic Hydraulic Testing for Discerning Fracture Network Connections

    Science.gov (United States)

    Becker, M.; Le Borgne, T.; Bour, O.; Guihéneuf, N.; Cole, M.

    2015-12-01

    Discrete fracture network (DFN) models often predict highly variable hydraulic connections between injection and pumping wells used for enhanced oil recovery, geothermal energy extraction, and groundwater remediation. Such connections can be difficult to verify in fractured rock systems because standard pumping or pulse interference tests interrogate too large a volume to pinpoint specific connections. Three field examples are presented in which periodic hydraulic tests were used to obtain information about hydraulic connectivity in fractured bedrock. The first site, a sandstone in New York State, involves only a single fracture at a scale of about 10 m. The second site, a granite in Brittany, France, involves a fracture network at about the same scale. The third site, a granite/schist in the U.S. State of New Hampshire, involves a complex network at scale of 30-60 m. In each case periodic testing provided an enhanced view of hydraulic connectivity over previous constant rate tests. Periodic testing is particularly adept at measuring hydraulic diffusivity, which is a more effective parameter than permeability for identify the complexity of flow pathways between measurement locations. Periodic tests were also conducted at multiple frequencies which provides a range in the radius of hydraulic penetration away from the oscillating well. By varying the radius of penetration, we attempt to interrogate the structure of the fracture network. Periodic tests, therefore, may be uniquely suited for verifying and/or calibrating DFN models.

  2. Effect of pumping chamber on performance of non-overload centrifugal pump

    Institute of Scientific and Technical Information of China (English)

    谷云庆; 吴登昊; 牟介刚; 蒋兰芳; 代东顺; 施瀚昱; 郑水华

    2015-01-01

    In order to specify the characteristics of un-overloaded centrifugal pumps, the IH100-65-200 pump was chosen as the model pump. Different calculation models for centrifugal pumps were established under different pumping chamber sectional parameters. In the numerical simulation of the centrifugal pumps flow field, the shaft power, head, efficiency, and the changes of the internal flow field under different sectional areas and sectional shapes were studied with the RNGk−εturbulence model, and the influence of the pumping chamber section characteristics of the non-overloaded centrifugal pumps were analyzed. The results show that sectional areas have a significant impact on the non-overload characteristics of centrifugal pumps. The shaft power and head of centrifugal pump are increasing with a lager sectional area, by which the gradient of head curves decreases. The efficiency is improved under a large flow rate condition, but the head and the efficiency are reduced at a small flow rate. It is also observed that the sectional shapes have less influence on the shaft power, the hydraulic performance and flow field characteristics of a centrifugal pump.

  3. Analysis of and H∞ Controller Design For An Electro-Hydraulic Servo Pressure Regulator

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole

    2011-01-01

    -circuit pumps are still hydraulically controlled, there is however still a need for being able to generate a hydraulic pilot pressure. The focus of the current paper is on the analysis and controller design of an electrohydraulic servo pressure regulator, which generates a hydraulic LS-pressure for a variable...... displacement pump based on an electrical reference. The paper first presents the considered system and an experimentally verified model of this. A linearized model and a stability analysis is then presented, based on which an H∞control strategy is selected. A nominal performance and a robustly stable...

  4. Reactive barriers: hydraulic performance and design enhancements.

    Science.gov (United States)

    Painter, B D M

    2004-01-01

    The remediation of contaminated ground water is a multibillion-dollar global industry. Permeable reactive barriers (PRBs) are one of the leading technologies being developed in the search for alternatives to the pump-and-treat method. Improving the hydraulic performance of these PRBs is an important part of maximizing their potential to the industry. Optimization of the hydraulic performance of a PRB can be defined in terms of finding the balance between capture, residence time, and PRB longevity that produces a minimum-cost acceptable design. Three-dimensional particle tracking was used to estimate capture zone and residence time distributions. Volumetric flow analysis was used for estimation of flow distribution across a PRB and in the identification of flow regimes that may affect the permeability or reactivity of portions of the PRB over time. Capture zone measurements extended below the base of partially penetrating PRBs and were measured upgradient from the portion of aquifer influenced by PRB emplacement. Hydraulic performance analysis of standard PRB designs confirmed previously presented research that identified the potential for significant variation in residence time and capture zone. These variations can result in the need to oversize the PRB to ensure that downgradient contaminant concentrations do not exceed imposed standards. The most useful PRB design enhancements for controlling residence time and capture variation were found to be customized downgradient gate faces, velocity equalization walls, deeper emplacement of the funnel than the gate, and careful manipulation of the hydraulic conductivity ratio between the gate and the aquifer.

  5. Operating pumps on minimum flow

    Energy Technology Data Exchange (ETDEWEB)

    Casada, D.A. [Oak Ridge National Lab., TN (United States); Li, Y.C. [Nuclear Regulatory Commission, Washington, DC (United States)

    1992-06-01

    The Nuclear Regulatory Commission (NRC) staff issued Information Notice (IN) 87-59 to alert all licensees to two miniflow design concerns identified by Westinghouse. The first potential problem discussed in this IN involves parallel pump operation. If the head/capacity curve of one of the parallel pumps is greater than the other, the weaker pump may be dead-headed when the pumps are operating at low-flow conditions. The other problem related to potential pump damage as a result of hydraulic instability during low-flow operation. In NRC Bulletin 88-04, dated May 5, 1988, the staff requested all licensees to investigate and correct, as applicable, the two miniflow design concerns. The staff also developed a Temporary Instruction, Tl 2515/105, dated January 29, 1990 to inspect for the adequacy of licensee response and follow-up actions to NRC Bulletin 88-04. Oak Ridge National Laboratory has reviewed utility responses to Bulletin 88-04 under auspices of the NRC`s Nuclear Plant Aging Research Program, and participated in several NRC inspections. Examples of actions that have been taken, an assessment of the overall industry response, and resultant conclusions and recommendations are presented.

  6. Operating pumps on minimum flow

    Energy Technology Data Exchange (ETDEWEB)

    Casada, D.A. (Oak Ridge National Lab., TN (United States)); Li, Y.C. (Nuclear Regulatory Commission, Washington, DC (United States))

    1992-01-01

    The Nuclear Regulatory Commission (NRC) staff issued Information Notice (IN) 87-59 to alert all licensees to two miniflow design concerns identified by Westinghouse. The first potential problem discussed in this IN involves parallel pump operation. If the head/capacity curve of one of the parallel pumps is greater than the other, the weaker pump may be dead-headed when the pumps are operating at low-flow conditions. The other problem related to potential pump damage as a result of hydraulic instability during low-flow operation. In NRC Bulletin 88-04, dated May 5, 1988, the staff requested all licensees to investigate and correct, as applicable, the two miniflow design concerns. The staff also developed a Temporary Instruction, Tl 2515/105, dated January 29, 1990 to inspect for the adequacy of licensee response and follow-up actions to NRC Bulletin 88-04. Oak Ridge National Laboratory has reviewed utility responses to Bulletin 88-04 under auspices of the NRC's Nuclear Plant Aging Research Program, and participated in several NRC inspections. Examples of actions that have been taken, an assessment of the overall industry response, and resultant conclusions and recommendations are presented.

  7. Hydraulic modelling of drinking water treatment plant operations

    Directory of Open Access Journals (Sweden)

    K. J. Borger

    2008-10-01

    Full Text Available For a drinking water treatment plant simulation, water quality models, a hydraulic model, a process-control model, an object model, data management, training and decision-support features and a graphic user interface have been integrated. The integration of a hydraulic model in the simulator is necessary to correctly determine the division of flows over the plant's lanes and, thus, the flow through the individual treatment units, based on valve positions and pump speeds. The flow through a unit is one of the most important parameters in terms of a unit's effectiveness. In the present paper, a new EPAnet library is presented with the typical hydraulic elements for drinking water treatment processes. Using this library, a hydraulic model was set up and validated for the drinking water treatment plant Harderbroek.

  8. Heat driven pulse pump

    Science.gov (United States)

    Benner, Steve M (Inventor); Martins, Mario S. (Inventor)

    2000-01-01

    A heat driven pulse pump includes a chamber having an inlet port, an outlet port, two check valves, a wick, and a heater. The chamber may include a plurality of grooves inside wall of the chamber. When heated within the chamber, a liquid to be pumped vaporizes and creates pressure head that expels the liquid through the outlet port. As liquid separating means, the wick, disposed within the chamber, is to allow, when saturated with the liquid, the passage of only liquid being forced by the pressure head in the chamber, preventing the vapor from exiting from the chamber through the outlet port. A plurality of grooves along the inside surface wall of the chamber can sustain the liquid, which is amount enough to produce vapor for the pressure head in the chamber. With only two simple moving parts, two check valves, the heat driven pulse pump can effectively function over the long lifetimes without maintenance or replacement. For continuous flow of the liquid to be pumped a plurality of pumps may be connected in parallel.

  9. Analysis of and H∞ Controller Design For An Electro-Hydraulic Servo Pressure Regulator

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole;

    2011-01-01

    -circuit pumps are still hydraulically controlled, there is however still a need for being able to generate a hydraulic pilot pressure. The focus of the current paper is on the analysis and controller design of an electrohydraulic servo pressure regulator, which generates a hydraulic LS-pressure for a variable......Currently mobile hydraulics is in a transition phase, where electronic sensors and digital signal processors are becoming standard on a high number of machines, hereby replacing hydraulic pilot lines and offering new possibilities with regard to both control and feasibility. As most open...... displacement pump based on an electrical reference. The paper first presents the considered system and an experimentally verified model of this. A linearized model and a stability analysis is then presented, based on which an H∞control strategy is selected. A nominal performance and a robustly stable...

  10. Ion-Pumping Microbial Rhodopsins

    Directory of Open Access Journals (Sweden)

    Hideki eKandori

    2015-09-01

    Full Text Available Rhodopsins are light-sensing proteins used in optogenetics. The word rhodopsin originates from the Greek words rhodo and opsis, indicating rose and sight, respectively. Although the classical meaning of rhodopsin is the red-colored pigment in our eyes, the modern meaning of rhodopsin encompasses photoactive proteins containing a retinal chromophore in animals and microbes. Animal and microbial rhodopsins possess 11-cis and all-trans retinal, respectively, to capture light in seven transmembrane α-helices, and photoisomerizations into all-trans and 13-cis forms, respectively, initiate each function. Ion-transporting proteins can be found in microbial rhodopsins, such as light-gated channels and light-driven pumps, which are the main tools in optogenetics. Light-driven pumps, such as archaeal H+ pump bacteriorhodopsin (BR and Cl- pump halorhodopsin (HR, were discovered in the 1970s, and their mechanism has been extensively studied. On the other hand, different kinds of H+ and Cl- pumps have been found in marine bacteria, such as proteorhodopsin (PR and Fulvimarina pelagi rhodopsin (FR, respectively. In addition, a light-driven Na+ pump was found, Krokinobacter eikastus rhodopsin 2 (KR2. These light-driven ion-pumping microbial rhodopsins are classified as DTD, TSA, DTE, NTQ and NDQ rhodopsins for BR, HR, PR, FR and KR2, respectively. Recent understanding of ion-pumping microbial rhodopsins is reviewed in this paper.

  11. FEMA DFIRM Hydraulic Structures

    Data.gov (United States)

    Minnesota Department of Natural Resources — This layer and accompanying attribute table is required whenever hydraulic structures are shown in the flood profile. It is also required if levees are shown on the...

  12. Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    2005-01-01

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

  13. A 6-DOF vibration isolation system for hydraulic hybrid vehicles

    Science.gov (United States)

    Nguyen, The; Elahinia, Mohammad; Olson, Walter W.; Fontaine, Paul

    2006-03-01

    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, for heavy duty vehicles such as large SUVs, trucks, and buses, which require more power, the hydraulic hybridization is a more efficient choice. In function, the hydraulic hybrid subsystem improves the fuel efficiency of the vehicle by recovering some of the energy that is otherwise wasted in friction brakes. Since the operation of the main component of HHVs involves with rotating parts and moving fluid, noise and vibration are an issue that affects both passengers (ride comfort) as well as surrounding people (drive-by noise). This study looks into the possibility of reducing the transmitted noise and vibration from the hydraulic subsystem to the vehicle's chassis by using magnetorheological (MR) fluid mounts. To this end, the hydraulic subsystem is modeled as a six degree of freedom (6-DOF) rigid body. A 6-DOF isolation system, consisting of five mounts connected to the pump/motor at five different locations, is modeled and simulated. The mounts are designed by combining regular elastomer components with MR fluids. In the simulation, the real loading and working conditions of the hydraulic subsystem are considered and the effects of both shock and vibration are analyzed. The transmissibility of the isolation system is monitored in a wide range of frequencies. The geometry of the isolation system is considered in order to sustain the weight of the hydraulic system without affecting the design of the chassis and the effectiveness of the vibration isolating ability. The simulation results shows reduction in the transmitted vibration force for different working cycles of

  14. Energy Efficiency Comparison between Hydraulic Hybrid and Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jia-Shiun Chen

    2015-05-01

    Full Text Available Conventional vehicles tend to consume considerable amounts of fuel, which generates exhaust gases and environmental pollution during intermittent driving cycles. Therefore, prospective vehicle designs favor improved exhaust emissions and energy consumption without compromising vehicle performance. Although pure electric vehicles feature high performance and low pollution characteristics, their limitations are their short driving range and high battery costs. Hybrid electric vehicles (HEVs are comparatively environmentally friendly and energy efficient, but cost substantially more compared with conventional vehicles. Hydraulic hybrid vehicles (HHVs are mainly operated using engines, or using alternate combinations of engine and hydraulic power sources while vehicles accelerate. When the hydraulic system accumulator is depleted, the conventional engine reengages; concurrently, brake-regenerated power is recycled and reused by employing hydraulic motor–pump modules in circulation patterns to conserve fuel and recycle brake energy. This study adopted MATLAB Simulink to construct complete HHV and HEV models for backward simulations. New European Driving Cycles were used to determine the changes in fuel economy. The output of power components and the state-of-charge of energy could be retrieved. Varying power component models, energy storage component models, and series or parallel configurations were combined into seven different vehicle configurations: the conventional manual transmission vehicle, series hybrid electric vehicle, series hydraulic hybrid vehicle, parallel hybrid electric vehicle, parallel hydraulic hybrid vehicle, purely electric vehicle, and hydraulic-electric hybrid vehicle. The simulation results show that fuel consumption was 21.80% lower in the series hydraulic hybrid vehicle compared to the series hybrid electric vehicle; additionally, fuel consumption was 3.80% lower in the parallel hybrid electric vehicle compared to the

  15. Oscillatory hydraulic testing as a strategy for NAPL source zone monitoring: Laboratory experiments

    Science.gov (United States)

    Zhou, YaoQuan; Cardiff, Michael

    2017-05-01

    Non-aqueous phase liquids (NAPLs) have a complex mode of transport in heterogeneous aquifers, which can result in pools and lenses of NAPLs (the ;source zone;) that are difficult to detect and can cause long-term contamination via slow dissolution into groundwater (the ;dissolved plume;). Characterizing the extent and evolution of NAPL contamination within the source zone is a useful strategy for designing and adapting appropriate remedial actions at many contaminated sites. As a NAPL flows into a given aquifer volume, the effective hydraulic conductivity (K) and specific storage (Ss) of the volume changes associated with the viscosity and compressibility of the impinging fluid, meaning that NAPL movement may be detectable with hydraulic testing. Recently, the use of oscillatory pumping tests - in which sinusoidal pumping variations are implemented and oscillatory pressure changes are detected at monitoring locations - has been suggested as a low-impact hydraulic testing strategy for characterizing aquifer properties (Cardiff et al., 2013; Zhou et al., 2016). Here, we investigate this strategy in an experimental laboratory sandbox where dyed vegetable oil is injected and allowed to migrate as a NAPL. Initial qualitative analyses demonstrate that measurable changes in pressure signal amplitude and phase provide clear evidence for NAPL plume emplacement and migration. Using the approach developed in Zhou et al. (2016), we then apply tomographic analyses to estimate the location of effective K changes (representing fluid changes) and their movement throughout time. This approach provides a method for monitoring ongoing NAPL movement without net extraction or injection of fluid, making it advantageous in field remediation applications.

  16. 快速锻造液压机动载因数分析%Dynamic load factor analysis for high-speed forging hydraulic press

    Institute of Scientific and Technical Information of China (English)

    高俊峰; 孙茂; 芦光荣; 刘崇民

    2012-01-01

    通过对20 MN下拉式快锻压机及对液压系统动载分析,介绍了快锻液压机组设计中动载因数的重要性;就如何降低液压冲击及振动提出了分析方法,尤其是分析了液压瞬变与流体在管道内的振动对机械系统振动的影响;提出了快锻液压机组设计中降低动载因数应遵守的准则.分析研究结果对液压系统设计中对泵、阀、管道等组件单元的选型与计算具有指导意义.%The importance of dynamic load factor in design of the high-speed hydraulic forging press was introduced through the dynamic load analysis for 20 MN pull-down type high-speed hydraulic forging press and its hydraulic system. The analytical method for how to reduce the hydraulic impact &- vibration was presented. The effect for the mechanical system vibration was especially analysed when the hydraulic transient and the fluid were vibrating in the piping. The criterion for the reducing dynamic load factor on the design of high-speed hydraulic forging press was provided. The analysis and research results have the guidance means for the model selection and calculation for pump, valve, piping and etc. in the hydraulic system designing.

  17. Applications of traditional pump design theory to artificial heart and CFD simulation

    Institute of Scientific and Technical Information of China (English)

    Yingpeng WANG; Xinwei SONG; Chuntong YING

    2008-01-01

    A novel heart pump model was obtained by improving the traditional axial pump design theory with the consideration of working and hydraulic situations for artificial hearts. The pump head range and the velocity triangle were introduced and an iterative approach was utilized for the initial model. Moreover, computational fluid dynamics (CFD) simulations were performed to determine relevant model parameters. The results show that this procedure can be used for designing a series of high-efficiency artificial heart pumps.

  18. Application of Ferrography to Fault Diagnosis of Hydraulic Systems

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper deals with research on the successful use of ferrography as a wear measurement method for condition monitoring and fault diagnosis of hydraulic systems.The analysis program and progression is discussed, and a case study for condition monitoring and fault diagnosis of hydraulic systems by means of ferrography is also reviewed.

  19. Research on the induction motor current signature for centrifugal pump at cavitation condition

    Directory of Open Access Journals (Sweden)

    Yin Luo

    2015-11-01

    Full Text Available Cavitation is a major undesirable phenomenon for centrifugal pump because it can cause hydraulic performance deterioration, pump damage by pitting and material erosion, and structural vibration and noise. Cavitation can appear within the entire range of the operating conditions; therefore, it must be prevented by all means. Sensorless monitoring technology based on motor current signature analysis is non-intrusive and economic for monitoring motor-driven equipment. Thus, this technology is suitable for centrifugal pump systems. The motor current signature for centrifugal pump load at the cavitation condition is the basis of this technology. However, systematic research is lacking on sensorless monitoring technology based on motor current signature. As a result, the tentative exploration for motor current signature at cavitation load was conducted in this study. The results show that the stator current is still a sinusoidal alternating current strictly to the law of sine. Moreover, the root mean square of the current fluctuates because of different flow regimes in the cavitation progress and decreases because vapor density is smaller than water density when cavitation is fully formed. For the stator current spectrum, the noise level, noise distribution, rotation speed, and vane pass frequency components show features in the cavitation process. These indicator indexes change according to the stage of cavitation development. Thus, the motor current signature analysis is found to be a feasible and cost-effective method for the stages of cavitation condition.

  20. Estimating Hydraulic Parameters When Poroelastic Effects Are Significant

    Science.gov (United States)

    Berg, S.J.; Hsieh, P.A.; Illman, W.A.

    2011-01-01

    For almost 80 years, deformation-induced head changes caused by poroelastic effects have been observed during pumping tests in multilayered aquifer-aquitard systems. As water in the aquifer is released from compressive storage during pumping, the aquifer is deformed both in the horizontal and vertical directions. This deformation in the pumped aquifer causes deformation in the adjacent layers, resulting in changes in pore pressure that may produce drawdown curves that differ significantly from those predicted by traditional groundwater theory. Although these deformation-induced head changes have been analyzed in several studies by poroelasticity theory, there are at present no practical guidelines for the interpretation of pumping test data influenced by these effects. To investigate the impact that poroelastic effects during pumping tests have on the estimation of hydraulic parameters, we generate synthetic data for three different aquifer-aquitard settings using a poroelasticity model, and then analyze the synthetic data using type curves and parameter estimation techniques, both of which are based on traditional groundwater theory and do not account for poroelastic effects. Results show that even when poroelastic effects result in significant deformation-induced head changes, it is possible to obtain reasonable estimates of hydraulic parameters using methods based on traditional groundwater theory, as long as pumping is sufficiently long so that deformation-induced effects have largely dissipated. ?? 2011 The Author(s). Journal compilation ?? 2011 National Ground Water Association.

  1. Degradation feature extraction of hydraulic pump based on morphological undecimated decomposition fusion and DCT high order singular entropy%基于形态非抽样融合与DCT高阶奇异熵的液压泵退化特征提取

    Institute of Scientific and Technical Information of China (English)

    孙健; 李洪儒; 王卫国; 许葆华

    2015-01-01

    针对轴向柱塞式液压泵性能退化中振动信号非线性强、退化特征提取困难等问题,提出基于形态非抽样融合与DCT(Discrete Cosine Transform)高阶奇异熵的退化特征提取方法。在一般框架下提出形态非抽样小波融合方法,通过构建特征能量因子筛选各分解层近似信号,据融合规则实现双通道振动信号融合重构、改善重构信号的特征信息;并利用DCT高阶谱分析法对融合信号进一步处理,通过奇异值分解分别计算Shannon、Tsallis奇异熵作为液压泵性能退化特征向量;用仿真信号及液压泵实测振动信号验证该方法的有效性。%Tosolvetheproblemthatvibrationsignalsofahydraulicpumpasusualarestronglynonlinearandits degradation features are difficult to extract,a degradation feature extraction method based upon morphological undecimated wavelet decomposition fusion (MUWDF)and DCT high order singular entropy was proposed.The MUWDF algorithm was presented under the general framework of morphological undecimated decomposition.The approximate signals of all decomposition layers were selected by using the feature energy factor and dual-channel vibration signals were fused according to the presented fusion rules so as to increase the proportion of feature information.On this basis,a high order spectrum analysis algorithm modified by DCT was proposed for further dealing with the fused signal.Shannon and Tsallis singular entropies,which were considered as fault degradation features of hydraulic pump,were respectively achieved by singular value decomposition.Finally,the proposed method was verified by using simulation signals and real pump vibration signals in various working conditions.

  2. An Approach to automatically optimize the Hydraulic performance of Blade System for Hydraulic Machines using Multi-objective Genetic Algorithm

    Science.gov (United States)

    Lai, Xide; Chen, Xiaoming; Zhang, Xiang; Lei, Mingchuan

    2016-11-01

    This paper presents an approach to automatic hydraulic optimization of hydraulic machine's blade system combining a blade geometric modeller and parametric generator with automatic CFD solution procedure and multi-objective genetic algorithm. In order to evaluate a plurality of design options and quickly estimate the blade system's hydraulic performance, the approximate model which is able to substitute for the original inside optimization loop has been employed in the hydraulic optimization of blade by using function approximation. As the approximate model is constructed through the database samples containing a set of blade geometries and their resulted hydraulic performances, it can ensure to correctly imitate the real blade's performances predicted by the original model. As hydraulic machine designers are accustomed to do design with 2D blade profiles on stream surface that are then stacked to 3D blade geometric model in the form of NURBS surfaces, geometric variables to be optimized were defined by a series profiles on stream surfaces. The approach depends on the cooperation between a genetic algorithm, a database and user defined objective functions and constraints which comprises hydraulic performances, structural and geometric constraint functions. Example covering optimization design of a mixed-flow pump impeller is presented.

  3. Types of Breast Pumps

    Science.gov (United States)

    ... Devices Consumer Products Breast Pumps Types of Breast Pumps Share Tweet Linkedin Pin it More sharing options ... used for feeding a baby. Types of Breast Pumps There are three basic types of breast pumps: ...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-01-10

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

  5. Numerical analysis of cavitation within slanted axial-flow pump

    Institute of Scientific and Technical Information of China (English)

    张睿; 陈红勋

    2013-01-01

    In this paper, the cavitating flow within a slanted axial-flow pump is numerically researched. The hydraulic and cavitation performance of the slanted axial-flow pump under different operation conditions are estimated. Compared with the experimental hydraulic performance curves, the numerical results show that the filter-based model is better than the standard k-e model to predict the parameters of hydraulic performance. In cavitation simulation, compared with the experimental results, the proposed numerical method has good predicting ability. Under different cavitation conditions, the internal cavitating flow fields within slanted axial-flow pump are investigated. Compared with flow visualization results, the major internal flow features can be effectively grasped. In order to explore the origin of the cavitation performance breakdown, the Boundary Vorticity Flux (BVF) is introduced to diagnose the cavitating flow fields. The analysis results indicate that the cavitation performance drop is relevant to the instability of cavitating flow on the blade suction surface.

  6. SITMILARITY LAW FOR HYDRAULIC DISTORTED MODEL

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Newton's general similarity criterion was applied to the distorted model. The results for the similarities of gravity force, drag force and pressure force are identical with those derived from relevant differential equations of fluid flow. And the selected limits of the distorted ratio were studied and the simulation of roughness coefficient of distorted model was conducted by means of hydraulic test.

  7. Should hydraulic tomography data be interpreted using geostatistical inverse modeling? A laboratory sandbox investigation

    Science.gov (United States)

    Illman, Walter A.; Berg, Steven J.; Zhao, Zhanfeng

    2015-05-01

    The robust performance of hydraulic tomography (HT) based on geostatistics has been demonstrated through numerous synthetic, laboratory, and field studies. While geostatistical inverse methods offer many advantages, one key disadvantage is its highly parameterized nature, which renders it computationally intensive for large-scale problems. Another issue is that geostatistics-based HT may produce overly smooth images of subsurface heterogeneity when there are few monitoring interval data. Therefore, some may question the utility of the geostatistical inversion approach in certain situations and seek alternative approaches. To investigate these issues, we simultaneously calibrated different groundwater models with varying subsurface conceptualizations and parameter resolutions using a laboratory sandbox aquifer. The compared models included: (1) isotropic and anisotropic effective parameter models; (2) a heterogeneous model that faithfully represents the geological features; and (3) a heterogeneous model based on geostatistical inverse modeling. The performance of these models was assessed by quantitatively examining the results from model calibration and validation. Calibration data consisted of steady state drawdown data from eight pumping tests and validation data consisted of data from 16 separate pumping tests not used in the calibration effort. Results revealed that the geostatistical inversion approach performed the best among the approaches compared, although the geological model that faithfully represented stratigraphy came a close second. In addition, when the number of pumping tests available for inverse modeling was small, the geological modeling approach yielded more robust validation results. This suggests that better knowledge of stratigraphy obtained via geophysics or other means may contribute to improved results for HT.

  8. Innovations in pump design - what are future directions?:

    OpenAIRE

    Ivantysynova, Monika

    2009-01-01

    Displacement-controlled actuators, advanced continuously variable transmissions and hydraulic hybrid power trains represent new technologies formobile hydraulic machines, off road and on road vehicles. These new technologies allow major fuel savings and reduced emissions, but they change the performance requirements of positive displacement pumps and motors. Additionally, the market demand for positive displacement machines will increase. This paper briefly discusses these technology trends a...

  9. East Mesa geothermal pump test facility (EMPTF). Final report

    Energy Technology Data Exchange (ETDEWEB)

    Olander, R.G.; Roberts, G.K.

    1984-11-28

    The design, fabrication and installation of a geothermal pump test facility (EMPFT) at the DOE geothermal site at East Mesa, California which is capable of testing 70 to 750 horsepower downwell pumps in a controlled geothermal environment were completed. The facility consists of a skid-mounted brine control module, a 160 foot below test well section, a hydraulic turbine for power recovery, a gantry-mounted hoist for pump handling and a 3-phase, 480 VAC, 1200 amp power supply to handle pump electric requirements. Geothermal brine is supplied to the EMPTF from one of the facility wells at East Mesa. The EMPTF is designed with a great amount of flexibility. The 20-inch diameter test well can accommodate a wide variety of pumps. The controls are interactive and can be adjusted to obtain a full complement of pump operation data, or set to maintain constant conditions to allow long-term testing with a minimum of operator support. The hydraulic turbine allows the EMPTF user to recover approximately 46% of the input pump power to help defray the operating cost of the unit. The hoist is provided for material handling and pump servicing and reduces the equipment that the user must supply for pump installation, inspection and removal.

  10. East Mesa geothermal pump test facility (EMPTF). Final report

    Energy Technology Data Exchange (ETDEWEB)

    Olander, R.G.; Roberts, G.K.

    1984-11-28

    Barber-Nichols has completed the design, fabrication and installation of a geothermal pump test facility at the DOE geothermal site at East Mesa, California which is capable of testing 70 to 750 horsepower downwell pumps in a controlled geothermal environment. The facility consists of a skid-mounted brine control module, a 160 foot below ground test well section, a hydraulic turbine for power recovery, a gantry-mounted hoist for pump handling and a 3-phase, 480 VAC, 1200 amp power supply to handle pump electric requirements. Geothermal brine is supplied to the EMPTF from one of the facility wells at East Mesa. The EMPTF is designed with a great amount of flexibility to attract the largest number of potential users. The 20-inch diameter test well can accommodate a wide variety of pumps. The controls are interactive and can be adjusted to obtain a full complement of pump operation data, or set to maintain constant conditions to allow long-term testing with a minimum of operator support. The hydraulic turbine allows the EMPTF user to recover approximately 46% of the input pump power to help defray the operating cost of the unit. The hoist is provided for material handling and pump servicing and reduces the equipment that the user must supply for pump installation, inspection and removal.

  11. Cavitation in Hydraulic Machinery

    Energy Technology Data Exchange (ETDEWEB)

    Kjeldsen, M.

    1996-11-01

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

  12. Hydraulic Conductivity Anisotropy of Heterogeneous Unsaturated Soils

    Science.gov (United States)

    Sun, Dongmin; Zhu, Jianting

    2010-05-01

    The effects of saturation degree (or capillary pressure) on hydraulic conductivity anisotropy in unsaturated soils have not been fully understood. This study developed an approach based on a conceptualization of combining the neural network based pedo-transfer function (PTF) results with the thin layer concept to explore the capillary pressure-dependent anisotropy in relation to soil texture and soil bulk density. The main objective is to examine how anisotropy characteristics are related to the relationships between hydraulic parameters and the basic soil attributes such as texture and bulk density. The hydraulic parameters are correlated with the texture and bulk density based on the pedo-transfer function (PTF) results. It is demonstrated that non-monotonic behavior of the unsaturated soil anisotropy in relation to the capillary pressure is only observed when the saturated hydraulic conductivity and the shape parameter are both related to the mean particle diameter. When only one hydraulic parameter is related to the grain diameter or when both are not related to the same attribute simultaneously, the unsaturated soil anisotropy increases monotonically with the increasing capillary pressure head. Therefore, it is suggested that this behavior is mainly due to the coupled dependence of the layer saturated hydraulic conductivities and the shape factors on the texture and bulk density. The correlation between the soil grain diameter and bulk density decreases the anisotropy effects of the unsaturated layered soils. The study illustrates that the inter-relationships of soil texture, bulk density, and hydraulic properties may cause vastly different characteristics of anisotropic unsaturated soils.

  13. Popeye Project: Hydraulic umbilical

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, K.G.; Williams, V.T.

    1996-12-31

    For the Popeye Project, the longest super-duplex hydraulic umbilical in the world was installed in the Gulf of Mexico. This paper reports on its selection and project implementation. Material selection addresses corrosion in seawater, water-based hydraulic fluid, and methanol. Five alternatives were considered: (1) carbon-steel with traditional coating and anodes, (2) carbon-steel coated with thermally sprayed aluminum, (3) carbon-steel sheathed in aluminum, (4) super-duplex, and (5) titanium. The merits and risks associated with each alternative are discussed. The manufacture and installation of the selected umbilical are also reported.

  14. FIELD TRIALS OF NEWLY DEVELOPED POSITIVE DISPLACEMENT SUBMERSIBLE PUMP

    Energy Technology Data Exchange (ETDEWEB)

    Rob Beard

    2003-10-01

    The purpose of this grant was to evaluate under real world conditions the performance of a new type of downhole pump, the hydraulically driven submersible diaphragm pump. This pump is supplied by Pumping Solutions Incorporated, Albuquerque NM. The original scope of the project was to install 10 submersible pumps, and compare that to 10 similar installations of rod pumps. As an operator, the system as tested was not ready for prime time, but has shown the ability to reduce costs, and increase production, if run times can be improved. The PSI group did improve the product and offered excellent service. The latest design appears to be much better, but more test data is needed to show short run life is not a problem. PSI and Beard Oil intend to continue testing the pump with non-government funding. The testing to date did not uncover any fundamental problems that would preclude the widespread use of this pump, and as an operator, I believe that with further improvement and testing, the pump can have a significant impact on stripper well costs. On the positive side, the pump was easy to run, was more power efficient then a rod pump, and is the only submersible that could handle the large quantities of solids typical of the production environment found at the Weber field and in CMB production. The product shows much promise for the future, and with continued design and testing, this type of submersible pump has the potential to become the standard of the industry.

  15. Hydraulic Arm Modeling via Matlab SimHydraulics

    OpenAIRE

    Věchet, Stanislav; Krejsa, Jiří

    2009-01-01

    System modeling is a vital tool for cost reduction and design process speed up in most engineering fields. The paper is focused on modeling of hydraulic arm as a part of intelligent prosthesis project, in the form of 2DOF open kinematic chain. The arm model combines mechanical, hydraulic and electric subsystems and uses Matlab as modeling tool. SimMechanics Matlab extension is used for mechanical part modeling, SimHydraulics toolbox is used for modeling of hydraulic circuit used for actuating...

  16. Analysis of nonlinearities and effects in direct drive electro-hydraulic position servo system

    Institute of Scientific and Technical Information of China (English)

    WANG Hong-jie; JI Tian-jing; MAO Xin-tao; LIU Quan-zhong

    2005-01-01

    The direct drive electro-hydraulic servo system is a new approach hydraulic system. It is much smaller and easier controlled than traditional systems and is a perfect energy saver. This paper will briefly introduce the popular nonlinearities in the electro-hydraulic system and analyse the effect of nonlinearities in direct drive electro-hydraulic position servo system by means of simulation research. Some valuable conclusions are given.

  17. HYDRAULICS, TUSCARAWAS COUNTY, OHIO, USA

    Data.gov (United States)

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

  18. Modelling of Hydraulic Robot

    DEFF Research Database (Denmark)

    Madsen, Henrik; Zhou, Jianjun; Hansen, Lars Henrik

    1997-01-01

    This paper describes a case study of identifying the physical model (or the grey box model) of a hydraulic test robot. The obtained model is intended to provide a basis for model-based control of the robot. The physical model is formulated in continuous time and is derived by application...

  19. Water Treatment Technology - Hydraulics.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    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…

  20. Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    2005-01-01

    The paper presents research results using IT-Tools for CAD and dynamic modelling, simulation, analysis, and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. Matlab/Simulink and CATIA are used as IT-Tools. The contributions include results from on-going...

  1. Non-stationary flow of hydraulic oil in long pipe

    Directory of Open Access Journals (Sweden)

    Hružík Lumír

    2014-03-01

    Full Text Available The paper deals with experimental evaluation and numerical simulation of non-stationary flow of hydraulic oil in a long hydraulic line. Non-stationary flow is caused by a quick closing of valves at the beginning and the end of the pipe. Time dependence of pressure is measured by means of pressure sensors at the beginning and the end of the pipe. A mathematical model of a given circuit is created using Matlab SimHydraulics software. The long line is simulated by means of segmented pipe. The simulation is verified by experiment.

  2. 振动压路机液压系统研究%On the Hydraulic Driving System Based on Full Hydraulic Vibratory Roller

    Institute of Scientific and Technical Information of China (English)

    杨平; 许炳照

    2011-01-01

    According to the application of hydraulic control technology of full hydraulic vibratory roller,the paper presents a design scheme of how to select hydraulic driving pumps and the rotators for the hydraulic component parts.Before selecting the methods of the hydraulic driving pumps and the rotators,the design scheme of the hydraulic system power and the engine should be mated properly,so as to determine the data of full hydraulic vibratory roller.%对全液压振动压路机的液压系统进行配置设计,在确定液压泵及液压马达型号规格后,计算液压系统功率与整机的功率合理匹配,从而确定全液压振动压路机各液压系统的参数,完成整机液压系统的合理配置。

  3. Hydraulic Tomography at North Campus Research Site: Let Data Tell the Story

    Science.gov (United States)

    Tso, C. H. M.; Yeh, T. C. J.

    2014-12-01

    Hydraulic tomography (HT) is a sequential cross-hole hydraulic test followed by inversion of the data to map the spatial distribution of aquifer hydraulic properties (Yeh and Liu, 2000). We provide a focused, qualitative discussion on the hydraulic tomography data reported in Berg and Illman (2011). At the North Campus Research Site (NCRS) of the University of Waterloo, 8 pumping tests are conducted sequentially at different locations of the well field while drawdown is monitored at 44 ports distributed at 8 other wells. Without conducting inverse modeling, we discuss the behavior of the drawdown curves and the temporal evolution head field in response to pumping location, heterogeneity in aquifer parameters (i.e. hydraulic conductivity (K) and specific storage (Ss)), flow regimes, and boundary conditions. We emphasize the importance and direct benefits for conducting hydraulic tomography surveys relies primarily on the collection of non-redundant data, not on the inverse models. This paper attempts to use an intuitive/logical approach to qualitative hydraulic tomography analysis. Our interpretation on the aquifer heterogeneity largely agrees with the intensive core sampling (i.e. local K measurements) and inverse modeling results. We conclude some of the inspection procedures can be beneficial before the inversion of data, while the quantitative and unifying estimation of hydraulic parameter fields can only be done using an inverse model.

  4. Estimation of hydraulic parameters from an unconfined aquifer test conducted in a glacial outwash deposit, Cape Cod, Massachusetts

    Science.gov (United States)

    Moench, A.F.; Garabedian, Stephen P.; LeBlanc, Denis R.

    2000-01-01

    An aquifer test conducted in a sand and gravel, glacial outwash deposit on Cape Cod, Massachusetts was analyzed by means of a model for flow to a partially penetrating well in a homogeneous, anisotropic unconfined aquifer. The model is designed to account for all significant mechanisms expected to influence drawdown in observation piezometers and in the pumped well. In addition to the usual fluid-flow and storage processes, additional processes include effects of storage in the pumped well, storage in observation piezometers, effects of skin at the pumped-well screen, and effects of drainage from the zone above the water table. The aquifer was pumped at a rate of 320 gallons per minute for 72-hours and drawdown measurements were made in the pumped well and in 20 piezometers located at various distances from the pumped well and depths below the land surface. To facilitate the analysis, an automatic parameter estimation algorithm was used to obtain relevant unconfined aquifer parameters, including the saturated thickness and a set of empirical parameters that relate to gradual drainage from the unsaturated zone. Drainage from the unsaturated zone is treated in this paper as a finite series of exponential terms, each of which contains one empirical parameter that is to be determined. It was necessary to account for effects of gradual drainage from the unsaturated zone to obtain satisfactory agreement between measured and simulated drawdown, particularly in piezometers located near the water table. The commonly used assumption of instantaneous drainage from the unsaturated zone gives rise to large discrepancies between measured and predicted drawdown in the intermediate-time range and can result in inaccurate estimates of aquifer parameters when automatic parameter estimation procedures are used. The values of the estimated hydraulic parameters are consistent with estimates from prior studies and from what is known about the aquifer at the site. Effects of

  5. HYDRAULIC UNITS FOR DRIVING SYSTEMS OF RUNNING EQUIPMENT IN ROAD CONSTRUCTION MACHINERY

    Directory of Open Access Journals (Sweden)

    A. Ja. Kotlobai

    2016-01-01

    Full Text Available Operational efficiency of multi-functional road construction machines depends on number of working bodies which are simultaneously performing technological operations. Systems for propulsion pto to the running equipment drive and active working bodies of road construction machines are developing in the way of using three-axis hydraulic drives. When designing a hydraulic system for road construction machinery dividing of power flow from propulsion to the running equipment drive and active working bodies is considered as rather essential problem. Leading companies do not pay attention to the development of flow divider designs, preferring to produce more expensive multi-flow pumps. One of the ways to increase efficiency of multi-functional road construction machinery is an implementation of running equipment hydraulic driving system based on a mono-aggregate pump unit which consists of a pump and a volumetric divider of power fluid flow. A principle of volumetric division and summing-up of power fluid flows, technical realization and methodology for calculation of key parameters of discrete flow distributors has been developed on the basis of discrete hydraulics regulations. The paper presents results of mathematical modeling of hydraulic systems equipped with the discrete flow distributor. Analysis of a dual-motor hydraulic drive operation has shown the following results: a discrete flow distributor ensures independent load mode of the current consumer circuit operation from the load mode of the second consumer circuit within a wide range of loads; rational value of working fluid flow discretization parameter is the following value interval k = 4–6, maximum value of parameter efficiency is reached when an angular velocity of a distributor rotor coincides with the angular velocity of a pump shaft; discrete flow distributor provides a possibility to change parameters of hydraulic flow feeding in consumers’ pressure lines within a wide range

  6. Hydraulic modelling of drinking water treatment plant operations

    Directory of Open Access Journals (Sweden)

    L. C. Rietveld

    2009-06-01

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

  7. Helical coil thermal hydraulic model

    Science.gov (United States)

    Caramello, M.; Bertani, C.; De Salve, M.; Panella, B.

    2014-11-01

    A model has been developed in Matlab environment for the thermal hydraulic analysis of helical coil and shell steam generators. The model considers the internal flow inside one helix and its associated control volume of water on the external side, both characterized by their inlet thermodynamic conditions and the characteristic geometry data. The model evaluates the behaviour of the thermal-hydraulic parameters of the two fluids, such as temperature, pressure, heat transfer coefficients, flow quality, void fraction and heat flux. The evaluation of the heat transfer coefficients as well as the pressure drops has been performed by means of the most validated literature correlations. The model has been applied to one of the steam generators of the IRIS modular reactor and a comparison has been performed with the RELAP5/Mod.3.3 code applied to an inclined straight pipe that has the same length and the same elevation change between inlet and outlet of the real helix. The predictions of the developed model and RELAP5/Mod.3.3 code are in fairly good agreement before the dryout region, while the dryout front inside the helical pipes is predicted at a lower distance from inlet by the model.

  8. Investigation on the gas pockets in a rotodynamic multiphase pump

    Science.gov (United States)

    Zhang, J. Y.; Li, Y. J.; Cai, S. J.; Zhu, H. W.; Zhang, Y. X.

    2016-05-01

    The appearance of gas pockets has an obvious impact on the performance of the rotodynamic multiphase pump. In order to study the formation of gas pockets in the pump and its effects on pump's performance, the unsteady numerical simulation and the visualization experiments were done to investigate gas pockets in a three-stage rotodynamic multiphase pump developed by authors. Meanwhile, the mixture of water and air was selected as the medium. According to the distributions of pressure, gas volume fraction and velocity vector in three compression cells in unsteady flow process, the process of the formation of gas pockets in the pump were analysed generally. The visualization experiments were used to verify the validity of the numerical simulation. The results will be benefit for the hydraulic design of the compression cell of rotodynamic multiphase pump.

  9. Investigation on the Reciprocity Principle with In-Situ Pumping Test in Confined Aquifer

    Science.gov (United States)

    Chen, Yong-Lin; Lin, Hong-Ru; Huang, Shao-Yang; Yeh, Tian-Chyi J.; Wen, Jet-Chau

    2016-04-01

    In this study, the pumping test of reciprocity between wells is developed for 11 wells located on campus of NYUST. The reciprocity analysis is conducted with the heterogeneous hydraulic properties distributions of the site. The mathematical theory of reciprocity implies that choose one as stimulation point and the other as observed response point in two known points at the same random field. Repeat the above action, the response behavior should have the reciprocity between the two points. However, the lack of literature with the field experiment to prove that reciprocity principle. Therefore, this study is expected to investigate the reciprocity of drawdown with the pumping test which will have heterogeneous hydraulic properties distributions obtained by inverse process. In general, there are two ways to investigate the reciprocity of pumping tests of two wells. One way is to evaluate the drawdown reciprocity of two sequential wells. From the evaluation the reciprocity of the drawdown behavior during the sequential pumping wells, the reciprocity of the drawdown behavior is investigated. The other one is to estimate cross-correlation between the drawdown behavior of the sequential pumping wells and heterogeneous hydraulic properties distributions. The reciprocity of between the drawdown and the heterogeneous hydraulic properties distributions is therefore can be investigated. This study proved the reciprocity of drawdown with the sequential pumping test and heterogeneous hydraulic properties distributions obtained by inverse method. Meanwhile, we proved the reciprocity is existed during the pumping test in the confined aquifer. Keywords: Reciprocity, Cross-correlation, Confined aquifer, Stimulation, Response

  10. Numerical Simulation of 3D Solid-Liquid Turbulent Flow in a Low Specific Speed Centrifugal Pump: Flow Field Analysis

    Directory of Open Access Journals (Sweden)

    Baocheng Shi

    2014-06-01

    Full Text Available For numerically simulating 3D solid-liquid turbulent flow in low specific speed centrifugal pumps, the iteration convergence problem caused by complex internal structure and high rotational speed of pump is always a problem for numeral simulation researchers. To solve this problem, the combination of three measures of dynamic underrelaxation factor adjustment, step method, and rotational velocity control means according to residual curves trends of operating parameters was used to improve the numerical convergence. Numeral simulation of 3D turbulent flow in a low specific speed solid-liquid centrifugal pump was performed, and the results showed that the improved solution strategy is greatly helpful to the numerical convergence. Moreover, the 3D turbulent flow fields in pumps have been simulated for the bottom ash-particles with the volume fraction of 10%, 20%, and 30% at the same particle diameter of 0.1 mm. The two-phase calculation results are compared with those of single-phase clean water flow. The calculated results gave the main region of the abrasion of the impeller and volute casing and improve the hydraulic design of the impeller in order to decrease the abrasion and increase the service life of the pump.

  11. Static Analysis of High-Performance Fixed Fluid Power Drive with a Single Positive-Displacement Hydraulic Motor

    Directory of Open Access Journals (Sweden)

    O. F. Nikitin

    2015-01-01

    Full Text Available The article deals with the static calculations in designing a high-performance fixed fluid power drive with a single positive-displacement hydraulic motor. Designing is aimed at using a drive that is under development and yet unavailable to find and record the minimum of calculations and maximum of existing hydraulic units that enable clear and unambiguous performance, taking into consideration an available assortment of hydraulic units of hydraulic drives, to have the best efficiency.The specified power (power, moment and kinematics (linear velocity or angular velocity of rotation parameters of the output element of hydraulic motor determine the main output parameters of the hydraulic drive and the useful power of the hydraulic drive under development. The value of the overall efficiency of the hydraulic drive enables us to judge the efficiency of high-performance fixed fluid power drive.The energy analysis of a diagram of the high-performance fixed fluid power drive shows that its high efficiency is achieved when the flow rate of fluid flowing into each cylinder and the magnitude of the feed pump unit (pump are as nearly as possible.The paper considers the ways of determining the geometric parameters of working hydromotors (effective working area or working volume, which allow a selection of the pumping unit parameters. It discusses the ways to improve hydraulic drive efficiency. Using the principle of holding constant conductivity allows us to specify the values of the pressure losses in the hydraulic units used in noncatalog modes. In case of no exact matching between the parameters of existing hydraulic power modes and a proposed characteristics of the pump unit, the nearest to the expected characteristics is taken as a working version.All of the steps allow us to create the high-performance fixed fluid power drive capable of operating at the required power and kinematic parameters with high efficiency.

  12. Transient Flows in a Pipe System with Pump Shut-Down and the Simultaneous Closing of a Spherical Valve

    Science.gov (United States)

    Zhang, Zh.

    2016-11-01

    Because of the limited value of the wave propagation speed in water the propagation of a pressure surge in transient flows can be tracked in the time series. This enables both the pressure head and the flow velocity in pipe flows to be determined as a function of both the coordinate along the pipe and the time. The propagation of the pressure surge includes both wave transmission and reflection. The latter occurs where the flow section is changed. The wave tracking method has been demonstrated as highly accurate and subsequently was applied to much more complex hydraulic systems, in which the pump is shut off and the spherical valve is simultaneously progressively closed. A combined four-quadrant characteristic of the pump and a spherical valve has been worked out, with which the computational procedure for the transient flow in the complex system could be significantly simplified. It has been demonstrated that not only the pressure surge in the hydraulic system but also the rotational speed of the pump could be satisfactorily computed. The computational algorithm has been demonstrated as quite simple, so that all calculations could be performed simply by means of the Microsoft Excel module.

  13. Inertial microfluidic pump

    Science.gov (United States)

    Kornilovitch, Pavel; Govyadinov, Alexander; Markel, David; Torniainen, Erik

    2015-11-01

    The inertial pump is powered by a microheater positioned near one end of a fluidic microchannel. As the microheater explosively boils the surrounding fluid, a vapor bubble expands and then collapses asymmetrically, resulting in net flow. Such devices become an effective means of transporting fluids at microscale. They have no moving parts and can be manufactured in large numbers using standard batch fabrication processes. In this presentation, physical principles behind pump operation are described, in particular the role of reservoirs in dissipating mechanical momentum and the expansion-collapse asymmetry. An effective one-dimensional dynamic model is formulated and solved. The model is compared with full three-dimensional CFD simulations and available experimental data. Potential applications of inertial micropumps are described.

  14. Unsteady Flow Analysis of Pump Mode Small Discharge Condition for a Francis Pump-turbine

    Science.gov (United States)

    Xiaoran, ZHAO; Yexiang, XIAO; Jincai, XU; Wei, XU; Jianbo, SUN; Zhengwei, WANG; Yangyang, YAO

    2016-11-01

    Unsteady flow phenomena, including vortex flow at runner inlet, helical backflow in the draft tube and numerous vortexes inside the guide vanes, can occur in pump-turbines under off design conditions at pump mode and can impact normal operation of pump-turbines. All of these phenomena cause serious pressure pulsation, which is quite different from cases in normal pump mode. There is also a difference of pressure pulsation frequency and amplitude in different place through the runner. This paper builds a whole flow passage of a model pump-turbine, simulates flow characteristics in runner by CFD technology, analyses pressure pulsation in the runner and explores the origin and mechanism of pressure pulsations. The SST-CC turbulence model is adopted to perform unsteady simulations of the pump-turbine under 0.46Q BEP small discharge condition at pump mode. Unsteady flow structures are proceeded combined with hydraulic loss and pressure amplitude spectra. The results indicates that there is complicated disordered flow inside the runner under 0.46Q BEP small discharge condition at pump mode, shows the amplitude and frequency characteristic of pressure pulsations through runner flow passage.

  15. Measuring swirl at a model scale of 1:1 for vertically submersible pumps

    Science.gov (United States)

    de Fockert, A.; Verhaart, F. I. H.; Czarnota, Z.; Rajkumar, S.

    2016-11-01

    Intakes of large pump stations are often designed with the aid of hydraulic modeling. The approach flow to pumps is tested for adverse hydraulic phenomena, such as pre-swirl, velocity variations and vortices. Most commonly, the limits for these phenomena are taken from the ANSI/HI 9.8-2012 standard - Rotodynamic Pumps for Pump Intake Design. The standard, however, does not explain how real pumps respond to swirl, uneven velocity distribution or vortices. The present joined study between Deltares and Xylem aims to bridge this gap. At the Deltares pump sump test facility, two identical pump compartments were built according to the ANSI/HI 9.8-2012 standard. In one of the compartments, a submersible, vertical column pump (Flygt PL7020) was installed, while a 1:1 scale model of that pump was installed in the other compartment. This arrangement allowed measurements of both pump performance (pump head and input power as a function of flow rate) and the model parameters (pre-rotation and vortex occurrence) for nearly identical approach flow conditions. By varying the geometry of the approach channels, the asymmetry of the flow was varied to produce various degrees of pre-swirl including values in excess of the commonly accepted limit of 5 degrees. This paper describes the measurement setup, the results of the measurements with the model pump and the measurement plan for the prototype pump.

  16. Theoretical aspects concerning working fluids in hydraulic systems

    Directory of Open Access Journals (Sweden)

    Tița Irina

    2017-01-01

    Full Text Available Among the properties of working fluid, viscosity is the most important as it regards especially to pumps. In order to study the behavior of hydrostatic transmission it is important to create a reliable research instrument for dynamic simulation. Our research expertise being in SimHydraulics consequently this instrument is the suitable block diagram. The purpose of this paper is to present the possible ways to customize the properties of the working fluid in the block diagram.

  17. FAULT DIAGNOSIS OF HYDRAULIC PUMPS USING IMPROVED NEURAL NETWORK~+

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    FAULTDIAGNOSISOFHYDRAULICPUMPSUSINGIMPROVEDNEURALNETWORK~+¥YangHongzhi;TanGuanzheng(DepartmentofAutomaticControlEngineering,C?..

  18. Piezo-Hydraulic Hybrid Pump for Flight Control Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Axis Engineering Technologies proposes a revolutionary new technology that can provide performance levels, in terms of output power, bandwidth and mass, previously...

  19. A novel shaft-less double suction mini pump

    Institute of Scientific and Technical Information of China (English)

    NISHI; Michihiro

    2010-01-01

    A novel double suction shaft-less mini pump was developed for heat control of small energy systems in this study.The mini pump impeller with an exit diameter of 40 mm was combined with the motor rotor supported by the hybrid dynamic bearing.The specific speed of the pump was 125 min-1 m3 min-1 m.The hydraulic performance of the pump was investigated experimen-tally under four rotational speeds.From the test results,it was recognized that the pump could provide a flow discharge of 5 L/min and head of 1.5 m,which are applicable for the heat control system of a 3 kW fuel cell.A three-dimensional turbulent flow simulation in the pump was also conducted near the design point.The numerical results showed that the average hydraulic performance of the mini pump was predicted reasonably.From the internal flow simulation,it was revealed that the favorable inflow condition upstream of impeller inlet could be attained by applying the double suction shaft-less design for the mini pump.

  20. The Performance test of Mechanical Sodium Pump with Water Environment

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Chungho; Kim, Jong-Man; Ko, Yung Joo; Jeong, Ji-Young; Kim, Jong-Bum [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Ko, Bock Seong; Park, Sang Jun; Lee, Yoon Sang [SAM JIN Industrial Co. LTD., Chunan (Korea, Republic of)

    2015-10-15

    As contrasted with PWR(Pressurized light Water Reactor) using water as a coolant, sodium is used as a coolant in SFR because of its low melting temperature, high thermal conductivity, the high boiling temperature allowing the reactors to operate at ambient pressure, and low neutron absorption cross section which is required to achieve a high neutron flux. But, sodium is violently reactive with water or oxygen like the other alkali metal. So Very strict requirements are demanded to design and fabricate of sodium experimental facilities. Furthermore, performance testing in high temperature sodium environments is more expensive and time consuming and need an extra precautions because operating and maintaining of sodium experimental facilities are very difficult. The present paper describes performance test results of mechanical sodium pump with water which has been performed with some design changes using water test facility in SAM JIN Industrial Co. To compare the hydraulic characteristic of model pump with water and sodium, the performance test of model pump were performed using vender's experimental facility for mechanical sodium pump. To accommodate non-uniform thermal expansion and to secure the operability and the safety, the gap size of some parts of original model pump was modified. Performance tests of modified mechanical sodium pump with water were successfully performed. Water is therefore often selected as a surrogate test fluid because it is not only cheap, easily available and easy to handle but also its important hydraulic properties (density and kinematic viscosity) are very similar to that of the sodium. Normal practice to thoroughly test a design or component before applied or installed in reactor is important to ensure the safety and operability in the sodium-cooled fast reactor (SFR). So, in order to estimate the hydraulic behavior of the PHTS pump of DSFR (600 MWe Demonstraion SFR), the performance tests of the model pump such as performance

  1. COMPUTATIONAL FLOW RATE FEEDBACK AND CONTROL METHOD IN HYDRAULIC ELEVATORS

    Institute of Scientific and Technical Information of China (English)

    Xu Bing; Ma Jien; Lin Jianjie

    2005-01-01

    The computational flow rate feedback and control method, which can be used in proportional valve controlled hydraulic elevators, is discussed and analyzed. In a hydraulic elevator with this method, microprocessor receives pressure information from the pressure transducers and computes the flow rate through the proportional valve based on pressure-flow conversion real time algorithm. This hydraulic elevator is of lower cost and energy consumption than the conventional closed loop control hydraulic elevator whose flow rate is measured by a flow meter. Experiments are carried out on a test rig which could simulate the load of hydraulic elevator. According to the experiment results, the means to modify the pressure-flow conversion algorithm are pointed out.

  2. Bayesian Approach for the Estimation of the Transmissivity Spatial Structure from Hydraulic Tomography Data

    Science.gov (United States)

    Demir, M. T.; Copty, N. K.; Trinchero, P.; Sanchez-Vila, X.

    2013-12-01

    Groundwater flow and contaminant transport are strongly influenced by the spatial variability of subsurface flow parameters. However, the interpretation of pumping test data used for subsurface characterization is normally performed using conventional methods that are based on the assumption of aquifer homogeneity. In recent years, hydraulic tomography has been proposed by some researchers to address the limitations of conventional site characterization methods. Hydraulic tomography involves the sequential pumping at one of a series of wells and observing the drawdown due to pumping at adjacent wells. The interpretation of the drawdown data from hydraulic tomography has been mostly performed using formal inverse procedures for the estimation of the spatial variability of the flow parameters. The purpose of this study is to develop a method for the estimation of the statistical spatial structure of the transmissivity from hydraulic tomography data. The method relies on the pumping test interpretation procedure of Copty et al. (2011), which uses the time-drawdown data and its time derivative at each observation well to estimate the spatially averaged transmissivity as a function of radial distance from the pumping well. A Bayesian approach is then used to identify the statistical parameters of the transmissivity field (i.e. variance and integral scale). The approach compares the estimated transmissivity as a function of radial distance from the pumping well to the probability density function of the spatially-averaged transmissivity. The method is evaluated using synthetically-generated pumping test data for a range of input parameters. This application demonstrates that, through a relatively simple procedure, additional information of the spatial structure of the transmissivity may be inferred from pumping tests data. Results indicate that as the number of available pumping tests increases, the reliability of the estimated transmissivity statistical parameters also

  3. Effects of model layer simplification using composite hydraulic properties

    Science.gov (United States)

    Kuniansky, Eve L.; Sepulveda, Nicasio; Elango, Lakshmanan

    2011-01-01

    Groundwater provides much of the fresh drinking water to more than 1.5 billion people in the world (Clarke et al., 1996) and in the United States more that 50 percent of citizens rely on groundwater for drinking water (Solley et al., 1998). As aquifer systems are developed for water supply, the hydrologic system is changed. Water pumped from the aquifer system initially can come from some combination of inducing more recharge, water permanently removed from storage, and decreased groundwater discharge. Once a new equilibrium is achieved, all of the pumpage must come from induced recharge and decreased discharge (Alley et al., 1999). Further development of groundwater resources may result in reductions of surface water runoff and base flows. Competing demands for groundwater resources require good management. Adequate data to characterize the aquifers and confining units of the system, like hydrologic boundaries, groundwater levels, streamflow, and groundwater pumping and climatic data for recharge estimation are to be collected in order to quantify the effects of groundwater withdrawals on wetlands, streams, and lakes. Once collected, three-dimensional (3D) groundwater flow models can be developed and calibrated and used as a tool for groundwater management. The main hydraulic parameters that comprise a regional or subregional model of an aquifer system are the hydraulic conductivity and storage properties of the aquifers and confining units (hydrogeologic units) that confine the system. Many 3D groundwater flow models used to help assess groundwater/surface-water interactions require calculating ?effective? or composite hydraulic properties of multilayered lithologic units within a hydrogeologic unit. The calculation of composite hydraulic properties stems from the need to characterize groundwater flow using coarse model layering in order to reduce simulation times while still representing the flow through the system accurately. The accuracy of flow models with

  4. Stochastic estimation of hydraulic transmissivity fields using flow connectivity indicator data

    Science.gov (United States)

    Freixas, G.; Fernà ndez-Garcia, D.; Sanchez-Vila, X.

    2017-01-01

    Most methods for hydraulic test interpretation rely on a number of simplified assumptions regarding the homogeneity and isotropy of the underlying porous media. This way, the actual heterogeneity of any natural parameter, such as transmissivity (T), is transferred to the corresponding estimates in a way heavily dependent on the interpretation method used. An example is a long-term pumping test interpreted by means of the Cooper-Jacob method, which implicitly assumes a homogeneous isotropic confined aquifer. The estimates obtained from this method are not local values, but still have a clear physical meaning; the estimated T represents a regional-scale effective value, while the log-ratio of the normalized estimated storage coefficient, indicated by ω', is an indicator of flow connectivity, representative of the scale given by the distance between the pumping and the observation wells. In this work we propose a methodology to use ω', together with sampled local measurements of transmissivity at selected points, to map the expected value of local T values using a technique based on cokriging. Since the interpolation involves two variables measured at different support scales, a critical point is the estimation of the covariance and crosscovariance matrices. The method is applied to a synthetic field displaying statistical anisotropy, showing that the inclusion of connectivity indicators in the estimation method provide maps that effectively display preferential flow pathways, with direct consequences in solute transport.

  5. Using the motor to monitor pump conditions

    Energy Technology Data Exchange (ETDEWEB)

    Casada, D. [Oak Ridge National Lab., TN (United States)

    1996-12-01

    When the load of a mechanical device being driven by a motor changes, whether in response to changes in the overall process or changes in the performance of the driven device, the motor inherently responds. For induction motors, the current amplitude and phase angle change as the shaft load changes. By examining the details of these changes in amplitude and phase, load fluctuations of the driven device can be observed. The usefulness of the motor as a transducer to improve the understanding of devices with high torque fluctuations, such as positive displacement compressors and motor-operated valves, has been recognized and demonstrated for a number of years. On such devices as these, the spectrum of the motor current amplitude, phase, or power normally has certain characteristic peaks associated with various load components, such as the piston stroke or gear tooth meshing frequencies. Comparison and trending of the amplitudes of these peaks has been shown to provide some indication of their mechanical condition. For most centrifugal pumps, the load fluctuations are normally low in torque amplitude, and as a result, the motor experiences a correspondingly lower level of load fluctuation. However, both laboratory and field test data have demonstrated that the motor does provide insight into some important pump performance conditions, such as hydraulic stability and pump-to-motor alignment. Comparisons of other dynamic signals, such as vibration and pressure pulsation, to motor data for centrifugal pumps are provided. The effects of inadequate suction head, misalignment, mechanical and hydraulic unbalance on these signals are presented.

  6. Heat pump field test in Maastricht, Netherlands. Praktijkproef met een warmtepomp in Limburg

    Energy Technology Data Exchange (ETDEWEB)

    Bassols, J. (Colibri Engineering Bureau (Netherlands)); Hamers, W.J.H. (NOVEM, Sittard (Netherlands)); Paulussen, M.J.M. (MEGA Limburg, Maastricht (Netherlands))

    1993-06-01

    A newly developed absorption heat pump has been fitted to an existing heating installation of the provincial government building in Maastricht, Netherlands. Major adjustments of the existing installation were necessary before the heat pump could be fitted in hydraulically. It is expected that considerable energy savings and reductions of NO-x and CO[sub 2] emissions can be realized.

  7. Efficiency limit factor analysis for the Francis-99 hydraulic turbine

    Science.gov (United States)

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

    2017-01-01

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

  8. Deciphering transmissivity and hydraulic conductivity of the aquifer by vertical electrical sounding (VES) experiments in Northwest Bangladesh

    Science.gov (United States)

    Sattar, Golam Shabbir; Keramat, Mumnunul; Shahid, Shamsuddin

    2016-03-01

    The vertical electrical soundings (VESs) are carried out in 24 selective locations of Chapai-Nawabganj area of northwest Bangladesh to determine the transmissivity and hydraulic conductivity of the aquifer. Initially, the transmissivity and hydraulic conductivity are determined from the pumping data of nearby available production wells. Afterwards, the T and K are correlated with geoelectrical resistance and the total resistivity of the aquifer. The present study deciphers the functional analogous relations of the geoelectrical resistance with the transmissivity and the total resistivity with the hydraulic conductivity of the aquifer in northwest Bangladesh. It has been shown that the given equations provide reasonable values of transmissivity and hydraulic conductivity where pumping test information is unavailable. It can be expected that the aquifer properties viz. transmissivity and hydraulic conductivity of geologically similar area can be determined with the help of the obtained equations by conducting VES experiments.

  9. Water Hammer in Pumped Sewer Mains

    DEFF Research Database (Denmark)

    Larsen, Torben

    This publication is intended for students and engineers seeking an introduction to the problem of water transients in pumped sewer and water mains. This is a subject of increasing interest because of the development of larger and more integrated systems. Consideration of transients is essential...... for the structural design of pipelines and for the planning of the proper function of the systems. The text is written by Torben Larsen, who is a professor of environmental hydraulics at the Department of Civil Engineering, Aalborg University. Torben Larsen has many years of experience with computer simulations...... of transients in pumped pipeline systems. This present publication can be understood as the second and revised edition of the pamphlet ”Transients in pumped sewer mains” (2006) which was published as a technical report by The EVA committee under The Danish Water Pollution Committee (The Danish Society...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-09-01

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

  11. Undular Hydraulic Jump

    Directory of Open Access Journals (Sweden)

    Oscar Castro-Orgaz

    2015-04-01

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

  12. LMFBR with booster pump in pumping loop

    Science.gov (United States)

    Rubinstein, H.J.

    1975-10-14

    A loop coolant circulation system is described for a liquid metal fast breeder reactor (LMFBR) utilizing a low head, high specific speed booster pump in the hot leg of the coolant loop with the main pump located in the cold leg of the loop, thereby providing the advantages of operating the main pump in the hot leg with the reliability of cold leg pump operation.

  13. Heat pump technology

    CERN Document Server

    Von Cube, Hans Ludwig; Goodall, E G A

    2013-01-01

    Heat Pump Technology discusses the history, underlying concepts, usage, and advancements in the use of heat pumps. The book covers topics such as the applications and types of heat pumps; thermodynamic principles involved in heat pumps such as internal energy, enthalpy, and exergy; and natural heat sources and energy storage. Also discussed are topics such as the importance of the heat pump in the energy industry; heat pump designs and systems; the development of heat pumps over time; and examples of practical everyday uses of heat pumps. The text is recommended for those who would like to kno

  14. Vertical pump turbine oil environmental evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Culver, G.

    1991-04-01

    In Oregon low-temperature geothermal injection well construction, siting and receiving formations requires approval by the Water Resources Department (OWRD). In addition, the Oregon Department of Environmental Quality (ODEQ) has regulations concerning injection. Conversations with the OWRD and ODEQ representatives indicated they were very concerned about the potential for contamination of the geothermal (and cooler but hydraulically connected) aquifers by oils and grease. Their primary concern was over the practice of putting paraffin, motor oils and other hydrocarbons in downhole heat exchanger (DHE) wells to prevent corrosion. They also expressed considerable concern about the use of oil in production well pumps since the fluids pumped would be injected. Oregon (and Idaho) prohibit the use of oil-lubricated pumps for public water supplies except in certain situations where non-toxic food-grade lubricants are used. Since enclosed-lineshaft oil-lubricated pumps are the mainstay of direct-use pumping equipment, the potential for restricting their use became a concern to the Geo-Heat Center staff. An investigation into alternative pump lubrication schemes and development of rebuttals to potential restrictions was proposed and approved as a contract task. (SM)

  15. Model Based Fault Detection in a Centrifugal Pump Application

    DEFF Research Database (Denmark)

    Kallesøe, Carsten; Cocquempot, Vincent; Izadi-Zamanabadi, Roozbeh

    2006-01-01

    A model based approach for fault detection in a centrifugal pump, driven by an induction motor, is proposed in this paper. The fault detection algorithm is derived using a combination of structural analysis, observer design and Analytical Redundancy Relation (ARR) design. Structural consideration...... is capable of detecting four different faults in the mechanical and hydraulic parts of the pump.......A model based approach for fault detection in a centrifugal pump, driven by an induction motor, is proposed in this paper. The fault detection algorithm is derived using a combination of structural analysis, observer design and Analytical Redundancy Relation (ARR) design. Structural considerations...

  16. Output Regulation of Large-Scale Hydraulic Networks with Minimal Steady State Power Consumption

    DEFF Research Database (Denmark)

    Jensen, Tom Nørgaard; Wisniewski, Rafal; De Persis, Claudio;

    2014-01-01

    that the system is overactuated is exploited for minimizing the steady state electrical power consumption of the pumps in the system, while output regulation is maintained. The proposed control actions are decentralized in order to make changes in the structure of the hydraulic network easy to implement.......An industrial case study involving a large-scale hydraulic network is examined. The hydraulic network underlies a district heating system, with an arbitrary number of end-users. The problem of output regulation is addressed along with a optimization criterion for the control. The fact...

  17. Design of a hydraulic actuator for active control of rotating machinery

    Science.gov (United States)

    Rashidi, Majid; Dirusso, Eliseo

    1991-01-01

    A hydraulic actuator is described which consists of a pump, a hydraulic servo-valve, and a thin elastic plate which transduces the generated pressure variations into forces acting on a mass which simulates the bearing of a rotor system. An actuator characteristic number is defined to provide a base for an optimum design of force actuators with combined weight, frequency, and force considerations. This characteristic number may also be used to compare hydraulic and electromagnetic force actuators. In tests, this actuator generated 182.3 Newton force at a frequency of 100 Hz and a displacement amplitude of 5.8 x 10 exp -5 meter.

  18. Pioneering Heat Pump Project

    Energy Technology Data Exchange (ETDEWEB)

    Aschliman, Dave [Indiana Inst. of Technology, Inc., Fort Wayne, IN (United States); Lubbehusen, Mike [Indiana Inst. of Technology, Inc., Fort Wayne, IN (United States)

    2015-06-30

    This project was initiated at a time when ground coupled heat pump systems in this region were limited in size and quantity. There were economic pressures with costs for natural gas and electric utilities that had many organizations considering ground coupled heat pumps; The research has added to the understanding of how ground temperatures fluctuate seasonally and how this affects the performance and operation of the heat pumps. This was done by using a series of temperature sensors buried within the middle of one of the vertical bore fields with sensors located at various depths below grade. Trending of the data showed that there is a lag in ground temperature with respect to air temperatures in the shoulder months, however as full cooling and heating season arrives, the heat rejection and heat extraction from the ground has a significant effect on the ground temps; Additionally it is better understood that while a large community geothermal bore field serving multiple buildings does provide a convenient central plant to use, it introduces complexity of not being able to easily model and predict how each building will contribute to the loads in real time. Additional controllers and programming were added to provide more insight into this real time load profile and allow for intelligent shedding of load via a dry cooler during cool nights in lieu of rejecting to the ground loop. This serves as a means to ‘condition’ the ground loop and mitigate thermal creep of the field, as is typically observed; and It has been observed when compared to traditional heating and cooling equipment, there is still a cost premium to use ground source heat pumps that is driven mostly by the cost for vertical bore holes. Horizontal loop systems are less costly to install, but do not perform as well in this climate zone for heating mode

  19. Dry vacuum pumps

    Science.gov (United States)

    Sibuet, R.

    2008-05-01

    For decades and for ultimate pressure below 1 mbar, oil-sealed Rotary Vane Pumps have been the most popular solution for a wide range of vacuum applications. In the late 80ies, Semiconductor Industry has initiated the development of the first dry roughing pumps. Today SC applications are only using dry pumps and dry pumping packages. Since that time, pumps manufacturers have developed dry vacuum pumps technologies in order to make them attractive for other applications. The trend to replace lubricated pumps by dry pumps is now spreading over many other market segments. For the Semiconductor Industry, it has been quite easy to understand the benefits of dry pumps, in terms of Cost of Ownership, process contamination and up-time. In this paper, Technology of Dry pumps, its application in R&D/industries, merits over conventional pumps and future growth scope will be discussed.

  20. Field study comparing the effect of hydraulic mixing on septic tank performance and sludge accumulation.

    Science.gov (United States)

    Almomani, Fares

    2016-01-01

    This study investigates the effect of hydraulic mixing on anaerobic digestion and sludge accumulation in a septic tank. The performance of a septic tank equipped with a hydraulic mixer was compared with that of a similar standard septic tank over a period of 10 months. The study was conducted in two phases: Phase-I--from May to November 2013 (6 months); Phase-II--from January to May 2014 (4 months). Hydraulic mixing effectively reduced the effluent biological oxygen demand (BOD) and total suspended solids, and reduced the sludge accumulation rate in the septic tank. The BOD removal efficiencies during Phase-II were 65% and 75% in the standard septic tank and a septic tank equipped with hydraulic mixer (Smart Digester™), respectively. The effect of hydraulic mixing reduced the rate of sludge accumulation from 0.64 cm/day to 0.27 cm/day, and increased the pump-out interval by a factor of 3.

  1. High-efficiency design of a mixed-flow pump

    Institute of Scientific and Technical Information of China (English)

    KIM; Jin-Hyuk; AHN; Hyung-Jin; KIM; Kwang-Yong

    2010-01-01

    High-efficiency design of a mixed-flow pump has been carried out based on numerical analysis of a three-dimensional viscous flow.For analysis,the Reynolds-averaged Navier-Stokes equations with a shear stress transport turbulence model were discretized by finite-volume approximations.Structured grid system was constructed in the computational domain,which has O-type grids near the blade surfaces and H/J-type grids in other regions.The numerical results were validated with experimental data for the heads and hydraulic efficiencies at different flow coefficients.The hydraulic efficiency at the design flow coefficient was evaluated with variation of the geometric variables,i.e.,the area of the discharge and length of the vane in the diffuser.The result has shown that the hydraulic efficiency of a mixed-flow pump at the design condition is improved by the modification of the geometry.

  2. 远洋船用伸缩折叠起重机液压系统设计%Marine telescopic folding crane hydraulic system design

    Institute of Scientific and Technical Information of China (English)

    卢志珍; 倪学虎; 舒希勇; 王成龙

    2012-01-01

    在分析伸缩折叠起重机对液压系统要求的基础上,针对起重机技术参数及客户要求提出了液压系统设计的思路.对关键液压元件——液压泵、液压马达、液压缸进行了计算选型,设计了液压原理图,并阐述了起重机液压回路的工作原理.%Based on the analysis of telescopic folding crane hydraulic system requirements,put forward the hydraulic system design thinking according to crane technical parameters and requirements of customers. Calculation and type selection of the key hydraulic components------hydraulic pump and hydraulic motor, hydraulic cylinder, design hydraulic principle diagram and expoundscrane hydraulic loop principle of work.

  3. Effects of model layer simplification using composite hydraulic properties

    Science.gov (United States)

    Sepulveda, Nicasio; Kuniansky, Eve L.

    2010-01-01

    The effects of simplifying hydraulic property layering within an unconfined aquifer and the underlying confining unit were assessed. The hydraulic properties of lithologic units within the unconfined aquifer and confining unit were computed by analyzing the aquifer-test data using radial, axisymmetric two-dimensional (2D) flow. Time-varying recharge to the unconfined aquifer and pumping from the confined Upper Floridan aquifer (USA) were simulated using 3D flow. Conceptual flow models were developed by gradually reducing the number of lithologic units in the unconfined aquifer and confining unit by calculating composite hydraulic properties for the simplified lithologic units. Composite hydraulic properties were calculated using either thickness-weighted averages or inverse modeling using regression-based parameter estimation. No significant residuals were simulated when all lithologic units comprising the unconfined aquifer were simulated as one layer. The largest residuals occurred when the unconfined aquifer and confining unit were aggregated into a single layer (quasi-3D), with residuals over 100% for the leakage rates to the confined aquifer and the heads in the confining unit. Residuals increased with contrasts in vertical hydraulic conductivity between the unconfined aquifer and confining unit. Residuals increased when the constant-head boundary at the bottom of the Upper Floridan aquifer was replaced with a no-flow boundary.

  4. Selection of design and determination of quality targets for vs6 pump stages

    Science.gov (United States)

    Tverdokhleb, I.; Yelin, A.

    2017-08-01

    A comparative analysis of VS6 pump type in the range of specific speed nq = 25...55 was carried out basing on information about analogous pumps produced by the world’s leading manufacturers. The focus was made on mass-dimensional characteristics of the pump stages. It was found that rational design of a diffuser with radial vanes provides lower material consumption at similar hydraulic characteristics compared to using a semi-axial vanes diffuser in the stage.

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

    CERN Document Server

    Parr, Andrew

    2011-01-01

    Nearly all industrial processes require objects to be moved, manipulated or subjected to some sort of force. Such movements and manipulations are frequently accomplished by means of devices driven by liquids (hydraulics) or air (pneumatics), the subject of this book. Hydraulics and Pneumatics is written by a practicing process control engineer as a guide to the successful operation of hydraulic and pneumatic systems for all engineers and technicians working with them. Keeping mathematics and theory to a minimum, this practical guide is thorough but accessible to technicians without a

  6. Modeling and control for hydraulic transmission of unmanned ground vehicle

    Institute of Scientific and Technical Information of China (English)

    王岩; 张泽; 秦绪情

    2014-01-01

    Variable pump driving variable motor (VPDVM) is the future development trend of the hydraulic transmission of an unmanned ground vehicle (UGV). VPDVM is a dual-input single-output nonlinear system with coupling, which is difficult to control. High pressure automatic variables bang-bang (HABB) was proposed to achieve the desired motor speed. First, the VPDVM nonlinear mathematic model was introduced, then linearized by feedback linearization theory, and the zero-dynamic stability was proved. The HABB control algorithm was proposed for VPDVM, in which the variable motor was controlled by high pressure automatic variables (HA) and the variable pump was controlled by bang-bang. Finally, simulation of VPDVM controlled by HABB was developed. Simulation results demonstrate the HABB can implement the desired motor speed rapidly and has strong robustness against the variations of desired motor speed, load and pump speed.

  7. Optimization of a Centrifugal Boiler Circulating Pump's Casing Based on CFD and FEM Analyses

    Directory of Open Access Journals (Sweden)

    Zhigang Zuo

    2014-04-01

    Full Text Available It is important to evaluate the economic efficiency of boiler circulating pumps in manufacturing process from the manufacturers' point of view. The possibility of optimizing the pump casing with respect to structural pressure integrity and hydraulic performance was discussed. CFD analyses of pump models with different pump casing sizes were firstly carried out for the hydraulic performance evaluation. The effects of the working temperature and the sealing ring on the hydraulic efficiency were discussed. A model with casing diameter of 0.875D40 was selected for further analyses. FEM analyses were then carried out on different combinations of casing sizes, casing wall thickness, and materials, to evaluate its safety related to pressure integrity, with respect to both static and fatigue strength analyses. Two models with forging and cast materials were selected as final results.

  8. [The design of bionic left ventricular auxiliary pump].

    Science.gov (United States)

    Jin, Henglin; Hu, Xiaobing; Du, Lei

    2015-01-01

    This paper reports a novel design of bionic left ventricular auxiliary pump, and the characteristic is that elastic diaphragm of pump driven by hydraulic, having smooth, reliable blood supply, can prevent blood clots, can use the flow sensor, pressure sensor detection showing the blood pressure and blood volume at the inlet and outlet of the pump. The pump can go with heart rate synchronization or asynchronous auxiliary by the R wave of human body's ECG. The design goal is realization of bionic throb. Through the animal experiment, the blood pressure waveforms are close to expectations, stable flow can stroke according to the set value, which prove that the pump can meet the requirement for heart disease patients for bionic left ventricular assistant.

  9. Modelling of Hydraulic Robot

    DEFF Research Database (Denmark)

    Madsen, Henrik; Zhou, Jianjun; Hansen, Lars Henrik

    1997-01-01

    This paper describes a case study of identifying the physical model (or the grey box model) of a hydraulic test robot. The obtained model is intended to provide a basis for model-based control of the robot. The physical model is formulated in continuous time and is derived by application...... of the laws of physics on the system. The unknown (or uncertain) parameters are estimated with Maximum Likelihood (ML) parameter estimation. The identified model has been evaluated by comparing the measurements with simulation of the model. The identified model was much more capable of describing the dynamics...... of the system than the deterministic model....

  10. Spinning hydraulic jump

    Science.gov (United States)

    Abderrahmane, Hamid; Kasimov, Aslan

    2013-11-01

    We report an experimental observation of a new symmetry breaking of circular hydraulic jump into a self-organized structure that consists of a spinning polygonal jump and logarithmic-spiral waves of fluid elevation downstream. The waves are strikingly similar to spiral density waves in galaxies. The fluid flow exhibits counterparts of salient morphological features of galactic flows, in particular the outflow from the center, jets, circum-nuclear rings, gas inflows toward the galactic center, and vortices. The hydrodynamic instability revealed here may have a counterpart that plays a role in the formation and sustainability of spiral arms in galaxies.

  11. Centrifugal pump handbook

    CERN Document Server

    Pumps, Sulzer

    2010-01-01

    This long-awaited new edition is the complete reference for engineers and designers working on pump design and development or using centrifugal pumps in the field. This authoritative guide has been developed with access to the technical expertise of the leading centrifugal pump developer, Sulzer Pumps. In addition to providing the most comprehensive centrifugal pump theory and design reference with detailed material on cavitation, erosion, selection of materials, rotor vibration behavior and forces acting on pumps, the handbook also covers key pumping applications topics and operational

  12. Investigation and Development of the Thermal Preparation System of the Trailbuilder Machinery Hydraulic Actuator

    Science.gov (United States)

    Konev, V.; Polovnikov, E.; Krut, O.; Merdanov, Sh; Zakirzakov, G.

    2017-07-01

    It’s determined that the main part of trailbuilders operated in the North is the technology equipped by the hydraulic actuator. Further development of the northern territories will demand using of various means and ways machinery thermal preparation, and also the machinery of the northern fulfillment. On this basis problems in equipment operation are defined. One of the main is efficiency supplying of a hydraulic actuator. On the basis of the operating conditions’ analysis of trailbuilder hydraulic actuator operation it is determined, that under low negative temperatures the means of thermal preparation are necessary. The existing systems warm up only a hydraulic tank or warming up of the hydro equipment before the machinery operation is carried out under loading with intensive wears. Thus, with the purpose to raise the efficiency of thermal hydraulic actuator, operated far from stationary bases autonomous, energy saving, not expensive in creation and operation systems are necessary. In accordance with the analysis of means and ways of the thermal preparation of the hydraulic actuator and the thermal balance calculations of the (internal) combustion engine the system of the hydraulic actuator heating is offered and is being investigated. It contains a local hydraulic actuator warming up and the system of internal combustion engine heat utilization. Within research operation conditions of the local hydraulic actuator heating are viewed and determined, taking into account constructive changes to the local hydraulic actuator heating. Mathematical modelling of the heat technical process in the modernized hydraulic actuator is considered. As a result temperature changes of the heat-transfer and the hydraulic cylinder in time are determined. To check the theoretical researches and to define dependences on hydraulic actuator warming up, the experimental installation is made. It contains the measuring equipment, a small tank with the heat exchanger of the burnt gases

  13. 46 CFR 28.880 - Hydraulic equipment.

    Science.gov (United States)

    2010-10-01

    ... hydraulic equipment and the adjacent work area. Protection shall be afforded to the operator of hydraulic... 46 Shipping 1 2010-10-01 2010-10-01 false Hydraulic equipment. 28.880 Section 28.880 Shipping... INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.880 Hydraulic equipment. (a) Each hydraulic system must...

  14. A New Type of Hydraulic Actuator Using Electrorheological Fluids

    Science.gov (United States)

    Wendt, Eckhard; Büsing, Klaus W.

    Electrorheological Fluids (ERF) are usually used in semi active damping elements, e.g. shock absorbers or engine mounts because of their continuously controllable shear stress. A totally new field of application may be achieved, if an ERF is used as a hydraulic fluid and not only as a control medium. In this case a fundamental need is the capability to produce a volume flow by using normal hydraulic pumps, e.g. gear pumps. The ERF and the hydraulic components both must have a long lifetime without unusual wear. Bayer AG has developed an ERF based on soft crosslinked PU-particles dispersed in silicone oil. These ERF are characterised by a low basic viscosity, a high ER-effect and a moderate conductivity. Compared with previous ERF where hard inorganic particles were used, the new fluid is not abrasive. It is foremostly this characteristic which gives the possibility of using the ERF in hydraulic systems with high shear rates and high shear stresses. The usage of ERF as hydraulic fluid allows the construction of proportional valves without mechanically driven parts. The control of the pressure drop over the valves is realised directly by an electrical signal. It is possible to realise actuators with very fast response times since the reaction time of ERF is within milliseconds. For demonstration purpose Bayer AG has built an actuator which is controlled by an electrorheological valve-block. The calculation of the dimension of this actuator and the valves will be shown and the realised response time will be demonstrated.

  15. Influence of Splitter Blades on the Cavitation Performance of a Double Suction Centrifugal Pump

    Directory of Open Access Journals (Sweden)

    Wei Yang

    2014-04-01

    Full Text Available In order to study the influence of splitter blades on double suction centrifugal pumps two impellers with and without splitter blades were investigated numerically and experimentally. Three-dimensional turbulence simulations with and without full cavitation model were applied to simulate the flow in the two pumps with different impellers. The simulation results agreed with the experiment results and the internal flows were analyzed. Both the numerical and experimental results show that by adding splitter blades the hydraulic performance and the cavitation performance of the pump are improved. The pump efficiency is increased especially at high flow rate condition. The pump high efficiency area is extended dramatically. At the same time since the splitter blades share some part of the blade loading, the pump critical NPSH value is decreased. Obvious pressure increase and velocity decrease at blade suction surface near leading edge were observed in the pump impeller with splitter blades. And the pump cavitation performance was improved consequently.

  16. Hydraulic conductivity of a firn aquifer system in southeast Greenland

    Science.gov (United States)

    Miller, Olivia L.; Solomon, D. Kip; Miège, Clément; Koenig, Lora S.; Forster, Richard R.; Montgomery, Lynn N.; Schmerr, Nicholas; Ligtenberg, Stefan R. M.; Legchenko, Anatoly; Brucker, Ludovic

    2017-05-01

    Some regions of the Greenland ice sheet, where snow accumulation and melt rates are high, currently retain substantial volumes of liquid water within the firn pore space throughout the year. These firn aquifers, found between 10-30 m below the snow surface, may significantly affect sea level rise by storing or draining surface meltwater. The hydraulic gradient and the hydraulic conductivity control flow of meltwater through the firn. Here we describe the hydraulic conductivity of the firn aquifer estimated from slug tests and aquifer tests at six sites located upstream of Helheim Glacier in southeastern Greenland. We conducted slug tests using a novel instrument, a piezometer with a heated tip that melts itself into the ice sheet. Hydraulic conductivity ranges between 2.5x10-5 and 1.1x10-3 m/s. The geometric mean of hydraulic conductivity of the aquifer is 2.7x10-4 m/s with a geometric standard deviation of 1.4 from both depth specific slug tests (analyzed using the Hvorslev method) and aquifer tests during the recovery period. Hydraulic conductivity is relatively consistent between boreholes and only decreases slightly with depth. The hydraulic conductivity of the firn aquifer is crucial for determining flow rates and patterns within the aquifer, which inform hydrologic models of the aquifer, its relation to the broader glacial hydrologic system, and its effect on sea level rise.

  17. Hydraulic Conductivity of a Firn Aquifer in Southeast Greenland

    Directory of Open Access Journals (Sweden)

    Olivia L. Miller

    2017-05-01

    Full Text Available Some regions of the Greenland ice sheet, where snow accumulation and melt rates are high, currently retain substantial volumes of liquid water within the firn pore space throughout the year. These firn aquifers, found between ~10 and 30 m below the snow surface, may significantly affect sea level rise by storing or draining surface meltwater. The hydraulic gradient and the hydraulic conductivity control flow of meltwater through the firn. Here we describe the hydraulic conductivity of the firn aquifer estimated from slug tests and aquifer tests at six sites located upstream of Helheim Glacier in southeastern Greenland. We conducted slug tests using a novel instrument, a piezometer with a heated tip that melts itself into the ice sheet. Hydraulic conductivity ranges between 2.5 × 10−5 and 1.1 × 10−3 m/s. The geometric mean of hydraulic conductivity of the aquifer is 2.7 × 10−4 m/s with a geometric standard deviation of 1.4 from both depth specific slug tests (analyzed using the Hvorslev method and aquifer tests during the recovery period. Hydraulic conductivity is relatively consistent between boreholes and only decreases slightly with depth. The hydraulic conductivity of the firn aquifer is crucial for determining flow rates and patterns within the aquifer, which inform hydrologic models of the aquifer, its relation to the broader glacial hydrologic system, and its effect on sea level rise.

  18. 46 CFR 56.50-45 - Circulating pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Circulating pumps. 56.50-45 Section 56.50-45 Shipping... APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-45 Circulating pumps. (a) A main circulating pump and emergency means for circulating water through the main condenser shall be provided....

  19. 46 CFR 56.50-35 - Condensate pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Condensate pumps. 56.50-35 Section 56.50-35 Shipping... APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-35 Condensate pumps. Two means shall be... independent of the main propelling machinery. If one of the independent feed pumps is fitted with a...

  20. Numerical simulation and analysis of solid-liquid two-phase three-dimensional unsteady flow in centrifugal slurry pump

    Institute of Scientific and Technical Information of China (English)

    吴波; 汪西力; 徐海良

    2015-01-01

    Based on RNGk-ε turbulence model and sliding grid technique, solid−liquid two-phase three-dimensional (3-D) unsteady turbulence of full passage in slurry pump was simulated by means of Fluent software. The effects of unsteady flow characteristics on solid−liquid two-phase flow and pump performance were researched under design condition. The results show that clocking effect has a significant influence on the flow in pump, and the fluctuation of flow velocity and pressure is obvious, particularly near the volute tongue, at the position of small sections of volute and within diffuser. Clocking effect has a more influence on liquid-phase than on solid-phase, and the wake-jet structure of relative velocity of solid-phase is less obvious than liquid-phase near the volute tongue and the impeller passage outlet. The fluctuation of relative velocity of solid-phase flow is 7.6% smaller than liquid-phase flow at the impeller outlet on circular path. Head and radial forces of the impeller are 8.1% and 85.7% of fluctuation, respectively. The results provide a theoretical basis for further research for turbulence, improving efficient, reducing the hydraulic losses and wear. Finally, field tests were carried out to verify the operation and wear of slurry pump.

  1. Numerical investigation of the effect of number of blades on centrifugal pump performance

    Science.gov (United States)

    Kocaaslan, O.; Ozgoren, M.; Babayigit, O.; Aksoy, M. H.

    2017-07-01

    In this study, the flow structure in a centrifugal pump was numerically investigated for the different blade numbers in the impeller between 5 and 9. The pump used in the study is a single-stage horizontal shafted centrifugal pump. The original pump impeller was designed as 7 blades for the parameters of flow rate Q=100 mł/h, head Hm=180 kPa and revolution n=1480 rpm. First, models of impellers with the different blade numbers between 5 and 9 and the volute section of the centrifugal pump were separately drawn using Solidworks software. Later, grid structures were generated on the flow volume of the pump. Last, the flow analyses were performed and the flow characteristics under different operational conditions were determined numerically. In the numerical analyses, k-ɛ turbulence model and standard wall functions were used to solve turbulent flow. Balance holes and surface roughness, which adversely affect the hydraulic efficiency of pumps, were also considered. The obtained results of the analyses show that the hydraulic torque and head values have increased with the application of higher number of the impeller blades. For the impellers with 5 and 9 blades on the design flow rate of 100 mł/h (Q/Qd=1), the hydraulic torque and head were found 49/59.1 Nm and 153.1/184.4 kPa, respectively. Subsequently the hydraulic efficiencies of each pump were calculated. As a result, the highest hydraulic efficiency on the design flow rate was calculated as 54.16% for the pump impeller having 8 blades.

  2. Influence of guide vane setting in pump mode on performance characteristics of a pump-turbine

    Science.gov (United States)

    Li, Deyou; Wang, Hongjie; Nielsen, Torbjørn K.; Gong, Ruzhi; Wei, Xianzhu; Qin, Daqing

    2016-11-01

    Performance characteristics in pump mode of pump-turbines are vital for the safe and effective operation of pumped storage power plants. They are resultant of Euler head (power input) and hydraulic losses (power dissipation). In this paper, 3-D steady simulations were performed under 13mm, 19mm and 25mm guide vane openings (GVOs). Three groups of operating points under the three GVOs were chosen based on experimental validation to investigate the influence of guide vane setting on flow patterns upstream and downstream. Analysed results show that, the guide vane setting will obviously change the flow pattern downstream, which in turn influences the flow upstream. It shows a strong effect on hydraulic losses in guide and stay vanes. In addition, at the large part load conditions, the change of GVO will increase the relative flow angle at the runner outlet. As a consequence, it decreases the Euler head. However, at other operating conditions, it only has a little influence on Euler head. Flow patterns in pump mode are very dependent on the GVO and discharge.

  3. FIELD TRIALS OF NEWLY DEVELOPED POSITIVE DISPLACEMENT SUBMERSIBLE PUMP

    Energy Technology Data Exchange (ETDEWEB)

    Rob Beard; Leland Traylor

    2002-12-01

    The purpose of this grant was to evaluate under real world conditions the performance of a new type of downhole pump, the hydraulically driven submersible diaphragm pump. This pump is supplied by Pumping Solutions Incorporated, Albuquerque NM. The original scope of the project was to install 10 submersible pumps, and compare that to 10 similar installations of rod pumps. As an operator, the system as tested was not ready for prime time. The PSI group did improve the product and offered excellent service. The latest design appears to be much better, but more test data is needed to show short run life is not a problem. This product should continue to be developed; the testing did not uncover any fundamental problems that would preclude it's widespread use. On the positive side, the pump was easy to run, was more power efficient then a rod pump, and is the only submersible that could handle the large quantities of solids typical of CBM production. The product shows much promise for the future, and with continued design and testing, this type of submersible pump has the potential to become the standard of the industry.

  4. Development and test of a plastic deep-well pump

    Science.gov (United States)

    Zhang, Q. H.; Gao, X. F.; Xu, Y.; Shi, W. D.; Lu, W. G.; Liu, W.

    2013-12-01

    To develop a plastic deep-well pump, three methods are proposed on structural and forming technique. First, the major hydraulic components are constructed by plastics, and the connection component is constructed by steel. Thus the pump structure is more concise and slim, greatly reducing its weight and easing its transportation, installation, and maintenance. Second, the impeller is designed by maximum diameter method. Using same pump casing, the stage head is greatly increased. Third, a sealing is formed by impeller front end face and steel end face, and two slots are designed on the impeller front end face, thus when the two end faces approach, a lubricating pair is formed, leading to an effective sealing. With above methods, the pump's axial length is greatly reduced, and its stage head is larger and more efficient. Especially, the pump's axial force is effectively balanced. To examine the above proposals, a prototype pump is constructed, and its testing results show that the pump efficiency exceeds the national standard by 6%, and the stage head is improved by 41%, meanwhile, its structure is more concise and ease of transportation. Development of this pump would provide useful experiences for further popularity of plastic deep-well pumps.

  5. Investigation of hydraulic transmission noise sources

    Science.gov (United States)

    Klop, Richard J.

    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.

  6. Hydraulic System Design of Electric Log Splitter%电动液压劈木机液压系统设计

    Institute of Scientific and Technical Information of China (English)

    孙增忠

    2014-01-01

    采用液压原理,设计了一款外形美观、移动方便、符合德国“GS”标准的电动卧式液压劈木机。针对设计开发过程中出现的保压和德国“GS”标准中要求双手操作的安全要求等问题,一是设计了三位三通液压控制阀,有效解决了双手操作问题;二是提高齿轮泵、液压控制阀等关键件的制造精度,加强关键件组装工序检验和控制手段,使劈木机压力得到了保证。结果表明:液压技术在电动工具中应用,具有一定的发展前景,电动卧式液压劈木机可以系列化,以满足不同客户要求。%Based on the hydraulic principle , it designs a good appearance , which is mobile convenience and up to the standard of Germany "GS"electric horizontal hydraulic log splitter .In view of this machine characteristic such as keeping the pressure and Germany "GS"hands operation safety in the standard requirement , it designs a hydraulic control valve with three tee to solve the problem of the hands operation , improves the manufacturing precision of the gear pump , hydraulic control valves , strengthens the key -module assembly process inspection and control means .These make the splitting machine obtain satisfactory pressure .The results show that the hy-draulic technology can be used in electric tools and have a certain development prospects .

  7. Automatic estimation of aquifer parameters using long-term water supply pumping and injection records

    Science.gov (United States)

    Luo, Ning; Illman, Walter A.

    2016-09-01

    Analyses are presented of long-term hydrographs perturbed by variable pumping/injection events in a confined aquifer at a municipal water-supply well field in the Region of Waterloo, Ontario (Canada). Such records are typically not considered for aquifer test analysis. Here, the water-level variations are fingerprinted to pumping/injection rate changes using the Theis model implemented in the WELLS code coupled with PEST. Analyses of these records yield a set of transmissivity ( T) and storativity ( S) estimates between each monitoring and production borehole. These individual estimates are found to poorly predict water-level variations at nearby monitoring boreholes not used in the calibration effort. On the other hand, the geometric means of the individual T and S estimates are similar to those obtained from previous pumping tests conducted at the same site and adequately predict water-level variations in other boreholes. The analyses reveal that long-term municipal water-level records are amenable to analyses using a simple analytical solution to estimate aquifer parameters. However, uniform parameters estimated with analytical solutions should be considered as first rough estimates. More accurate hydraulic parameters should be obtained by calibrating a three-dimensional numerical model that rigorously captures the complexities of the site with these data.

  8. Hydraulics. FOS: Fundamentals of Service.

    Science.gov (United States)

    John Deere Co., Moline, IL.

    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…

  9. Alternative backing up pump for turbomolecular pumps

    Science.gov (United States)

    Myneni, Ganapati Rao

    2003-04-22

    As an alternative to the use of a mechanical backing pump in the application of wide range turbomolecular pumps in ultra-high and extra high vacuum applications, palladium oxide is used to convert hydrogen present in the evacuation stream and related volumes to water with the water then being cryo-pumped to a low pressure of below about 1.e.sup.-3 Torr at 150.degree. K. Cryo-pumping is achieved using a low cost Kleemenco cycle cryocooler, a somewhat more expensive thermoelectric cooler, a Venturi cooler or a similar device to achieve the required minimization of hydrogen partial pressure.

  10. Study on the effect of the impeller and diffuser blade number on reactor coolant pump performances

    Science.gov (United States)

    Long, Y.; Yin, J. L.; Wang, D. Z.; Li, T. B.

    2016-05-01

    In this paper, CFD approach was employed to study how the blade number of impeller and diffuser influences reactor coolant pump performances. The three-dimensional pump internal flow channel was modelled by pro/E software, Reynolds-averaged Naiver-Stokes equations with the k-ε turbulence model were solved by the computational fluid dynamics software CFX. By post-processing on the numerical results, the performance curves of reactor coolant pump were obtained. The results are as follows, with the blade number of the impeller increasing, the head of the pump with different diffuser universally increases in the 8Q n∼1.2Q n conditions, and at different blade number of the diffuser, the head increases with the blade number of the impeller increasing. In 1.0Q n condition, when the blades number combination of impeller and diffuser chooses 4+16, 7+14 and 6+18, the head curves exist singular points. In 1.2Q n condition, the head curve still exists singular point in 6+18. With the blade number of the impeller increasing, the efficiency of the pump with different diffuser universally decreases in the 0.8Q n and 1.0Q n conditions, but in 1.2Q n condition, the efficiency of the pump with different diffuser universally increases. In 1.0Q n condition, the impellers of 4 and 5 blades are better. When the blade number combination of impeller and diffuser choose 4+11, 4+17, 4+18, 5+12, 5+17 and 5+18, the efficiencies relatively have higher values. With the blade number of the impeller increasing, the hydraulic shaft power of the pump with different diffuser universally increases in the 0.8Q n∼1.2Q n conditions, and with the blade number of the diffuser increasing, the power of different impeller overall has small fluctuation, but tends to be uniform. This means the increase of the diffuser blade number has less influence on shaft power.The influence on the head and flow by the matching relationship of the blades number between impeller and diffuser is very complicated, which

  11. The hydraulic fracturing of geothermal formations

    Energy Technology Data Exchange (ETDEWEB)

    Naceur, K. Ben; Economides, M.J.; Schlumberger, Dowell

    1988-01-01

    Hydraulic fracturing has been attempted in geothermal formations as a means to stimulate both production and injection wells. Since most geothermal formations contain fissures and on occasion massive natural fissures, the production behavior of the man-made fractures results in certain characteristic trends. A model is offered that allows the presence of a finite or infinite conductivity fracture intercepting a fissured medium. The method is based on a numerical discretization of the formation allowing transient interporosity flow. Type curves for pressure drawdown and cumulative production are given for infinite acting and closed reservoirs. Since most of the fissured formations exhibit a degree of anisotropy, the effects of the orientation of the hydraulic fracture with respect to the fissure planes, and of the ratio between the directional permeabilities are then discussed. Guidelines are offered as to the size of appropriate stimulation treatments based on the observed fissured behavior of the reservoir.

  12. A superelement-based method for computing unsteady three-dimensional potential flows in hydraulic turbomachines

    NARCIS (Netherlands)

    Kruyt, N.P.; Esch, van B.P.M.; Jonker, J.B.

    1999-01-01

    A numerical method is presented for the computation of unsteady, three-dimensional potential flows in hydraulic pumps and turbines. The superelement method has been extended in order to eliminate slave degrees of freedom not only from the governing Laplace equation, but also from the Kutta condition

  13. Pressure Regulation in Nonlinear Hydraulic Networks by Positive and Quantized Controls

    NARCIS (Netherlands)

    Persis, Claudio De; Kallesøe, Carsten Skovmose

    2011-01-01

    We investigate an industrial case study of a system distributed over a network, namely, a large-scale hydraulic network which underlies a district heating system. The network comprises an arbitrarily large number of components (valves, pipes, and pumps). After introducing the model for this class of

  14. Hydraulic Stability of Accropode Armour

    DEFF Research Database (Denmark)

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

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

  15. Hydraulic Stability of Accropode Armour

    DEFF Research Database (Denmark)

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

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

  16. HYDRAULIC CHARACTERISTICS OF SLIT-TYPE ENERGY DISSIPATERS

    Institute of Scientific and Technical Information of China (English)

    WU Jian-hua; MA Fei; YAO Li

    2012-01-01

    Slit-Type Energy Dissipater (STED) has been a kind of important devices for energy dissipation.The flow through the STED is longitudinally extended and the velocity is decreased by means of the cross-section increase of the flow,which is closely related to geometric and hydraulic parameters of the STED.Therefore,it is necessary to investigate and control the hydraulic conditions through the STED,including the nappe section form,the conversion condition,and the effect of energy dissipation with the geometric and hydraulic parameters.In the present work,"I-type" and "T-type" nappe forms were experimentally classified,the conversion conditions of the nappe forms were empirically provided,and the effects of geometric parameters of the STED on energy dissipation were roughly analyzed.It is concluded that the contraction angle of the STED is a key factor influencing the hydraulic characteristics of the STED.

  17. Virtual prototype simulation on underwater hydraulic impingement shovel

    Institute of Scientific and Technical Information of China (English)

    LIU He-ping; LUO A-ni; MENG Qing-xin

    2007-01-01

    The virtual prototype technology is applied to the design of the hydraulic impingement shovel,which is to increase the reliability of the design. The work principle of hydraulic impingement shovel is expatiated, and its dynamic equations are established. The 3D model of virtual prototype is built by PRO/E. Then the couple between the mechanical body of prototype and the hydraulic system is completed by virtue of ADAMS. Finally, the simulation is made on the virtual prototype. The simulation results show that the design of underwater hydraulic impingement shovel is rational. The virtual prototype technology could lay sound foundation of successful manufacturing of physical prototype for the first time and offer highly effective and feasible means for the design and production of underwater equipments.

  18. The lunar thermal ice pump

    Energy Technology Data Exchange (ETDEWEB)

    Schorghofer, Norbert [Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii, Honolulu, HI 96822 (United States); Aharonson, Oded, E-mail: norbert@hawaii.edu [Helen Kimmel Center for Planetary Science, Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 76100 (Israel)

    2014-06-20

    It has long been suggested that water ice can exist in extremely cold regions near the lunar poles, where sublimation loss is negligible. The geographic distribution of H-bearing regolith shows only a partial or ambiguous correlation with permanently shadowed areas, thus suggesting that another mechanism may contribute to locally enhancing water concentrations. We show that under suitable conditions, water molecules can be pumped down into the regolith by day-night temperature cycles, leading to an enrichment of H{sub 2}O in excess of the surface concentration. Ideal conditions for pumping are estimated and found to occur where the mean surface temperature is below 105 K and the peak surface temperature is above 120 K. These conditions complement those of the classical cold traps that are roughly defined by peak temperatures lower than 120 K. On the present-day Moon, an estimated 0.8% of the global surface area experiences such temperature variations. Typically, pumping occurs on pole-facing slopes in small areas, but within a few degrees of each pole the equator-facing slopes are preferred. Although pumping of water molecules is expected over cumulatively large areas, the absolute yield of this pump is low; at best, a few percent of the H{sub 2}O delivered to the surface could have accumulated in the near-surface layer in this way. The amount of ice increases with vapor diffusivity and is thus higher in the regolith with large pore spaces.

  19. Large electromagnetic pumps. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Kilman, G.B.

    1976-01-01

    The development of large electromagnetic pumps for the liquid metal heat transfer systems of fission reactors has progressed for a number of years. Such pumps are now planned for fusion reactors and solar plants as well. The Einstein-Szilard (annular) pump has been selected as the preferred configuration. Some of the reasons that electromagnetic pumps may be preferred over mechanical pumps and why the annular configuration was selected are discussed. A detailed electromagnetic analysis of the annular pump, based on slug flow, is presented. The analysis is then used to explore the implications of large size and power on considerations of electromagnetic skin effect, geometric skin effect and the cylindrical geometry.

  20. Hydraulic Yaw System

    DEFF Research Database (Denmark)

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

    As wind turbines increase in size, combined with increased lifetime demands, new methods for load reduction needs to be examined. One method is to make the yaw system of the turbine soft/flexible and hereby dampen the loads to the system, which is the focus of the current paper. By utilizing...... the HAWC2 aeroelastic code and an extended model of the NREL 5MW turbine combined with a simplified linear model of the turbine, the parameters of the soft yaw system are optimized to reduce loading in critical components. Results shows that a significant reduction in fatigue and extreme loads to the yaw...... system and rotor shaft when utilizing the soft yaw drive concept compared to the original stiff yaw system. The physical demands of the hydraulic yaw system are furthermore examined for a life time of 20 years. Based on the extrapolated loads, the duty cycles show that it is possible to construct...

  1. Electro Hydraulic Hitch Control

    DEFF Research Database (Denmark)

    Hansen, M. R.; Andersen, T. O.; Nielsen, B.

    2003-01-01

    system for agricultural applications and driving for transportation. During tranport phases, the lack of suspension causes the vehicle to bounce and pitch, and makes it difficalt to control. Many systems have been proposed to cope with the oscillatory behavior, and different solutions exist. Common......This paper present and discusses R&D results on electro hydraulic hitch control for off-road vehicle, in particular active damping of oscillation occuring on tractors. The research deals with analysis and control of the oscillations occuring on tractors which are design without any susspection...... for most of the systems are that they operate on the hydrailc actuators generally providing the motive forces for moving the implement and/or attachment, typically a plough. The basic idea and physical working principle are to use the implement, moveable relative to the vehicle, as a damper mass. The paper...

  2. Patient-controlled analgesic infusion pumps.

    Science.gov (United States)

    2001-05-01

    Patient-controlled analgesic (PCA) infusion devices allow patients to self-administer narcotic analgesics within the limits prescribed by the physician. PCA therapy is typically used for postoperative, obstetric, terminally ill, and trauma patients. PCA pumps deliver solutions intravenously, subcutaneously, or epidurally and allow patient activation by means of a pendant button on a cord connected to the pump or a button directly on the pump. We evaluated nine PCA pumps from six suppliers. Three of these pumps are syringe-type, while the others use cassette-based fluid delivery. Because PCA pumps have often been cited as examples of devices that contribute to medical error (the most significant risk connected with PCA infusion is overmedication), the accident resistance of each device weighed heavily in our testing. The pumps we tested exhibit varying levels of performance, resistance to accidents and tampering, and ease of use. We rate six of them Acceptable. While none of the six units stands out as ideal, they meet most of our criteria, and we consider them somewhat better choices than the rest. We rate one other pump Acceptable (with Conditions) because, in one of its operating modes, it has a drawback that could be dangerous to patients; we consider its use acceptable only if the hospital doesn't employ the operating mode in question. Finally, we rate two pumps Not Recommended because they both have a significant number of disadvantages.

  3. Pythagorean means and Carnot machines: When music meets heat

    CERN Document Server

    Johal, Ramandeep S

    2016-01-01

    Some interesting relations between Pythagorean means (arithmetic, geometric and harmonic means) and the coefficients of performance of reversible Carnot machines (heat engine, refrigerator and heat pump) are discussed.

  4. The terrestrial silica pump.

    Directory of Open Access Journals (Sweden)

    Joanna C Carey

    Full Text Available Silicon (Si cycling controls atmospheric CO(2 concentrations and thus, the global climate, through three well-recognized means: chemical weathering of mineral silicates, occlusion of carbon (C to soil phytoliths, and the oceanic biological Si pump. In the latter, oceanic diatoms directly sequester 25.8 Gton C yr(-1, accounting for 43% of the total oceanic net primary production (NPP. However, another important link between C and Si cycling remains largely ignored, specifically the role of Si in terrestrial NPP. Here we show that 55% of terrestrial NPP (33 Gton C yr(-1 is due to active Si-accumulating vegetation, on par with the amount of C sequestered annually via marine diatoms. Our results suggest that similar to oceanic diatoms, the biological Si cycle of land plants also controls atmospheric CO(2 levels. In addition, we provide the first estimates of Si fixed in terrestrial vegetation by major global biome type, highlighting the ecosystems of most dynamic Si fixation. Projected global land use change will convert forests to agricultural lands, increasing the fixation of Si by land plants, and the magnitude of the terrestrial Si pump.

  5. The Maintenance of Heading Machine Hydraulic System%掘进机液压系统的维护

    Institute of Scientific and Technical Information of China (English)

    卞丽霞

    2011-01-01

    The paper mainly discussed the rotation of hydraulic tank, oil return filter system and the axial piston pump of heading machine's hydraulic system, the adjustment of axial piston pump, relief valve pressure and one-way throttle valve and the maintenance of hydraulic system and the using of hydraulic components.%本文主要阐述了掘进机液压系统的液压油箱、液压系统的回油过滤器、轴向柱塞泵的旋转、轴向柱塞泵、溢流阀压力的调整、单向节流阀的调整、液压系统维护、液压元件的使用等维护.

  6. International Space Station power module thermal control system hydraulic performance

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, V. [Boeing North American, Inc., Canoga Park, CA (United States). Rocketdyne Div.

    1997-12-31

    The International Space Station (ISS) uses four photovoltaic power modules (PVMs) to provide electric power for the US On-Orbit Segment. The PVMs consist of photovoltaic arrays (PVAs), orbit replaceable units (ORUs), photovoltaic radiators (PVRs), and a thermal control system (TCS). The PVM TCS function is to maintain selected PVM components within their specified operating ranges. The TCS consists of the pump flow control subassembly (PFCS), piping system, including serpentine tubing for individual component heat exchangers, headers/manifolds, fluid disconnect couplings (FQDCs), and radiator (PVR). This paper describes the major design requirements for the TCS and the results of the system hydraulic performance predictions in regard to these requirements and system component sizing. The system performance assessments were conducted using the PVM TCS fluid network hydraulic model developed for predicting system/component pressure losses and flow distribution. Hardy-Cross method of iteration was used to model the fluid network configuration. Assessments of the system hydraulic performance were conducted based on an evaluation of uncertainties associated with the manufacturing and design tolerances. Based on results of the analysis, it was concluded that all design requirements regarding system performance could be met. The hydraulic performance range, enveloping possible system operating parameter variations was determined.

  7. Hydraulic conductivity of compacted zeolites.

    Science.gov (United States)

    Oren, A Hakan; Ozdamar, Tuğçe

    2013-06-01

    Hydraulic conductivities of compacted zeolites were investigated as a function of compaction water content and zeolite particle size. Initially, the compaction characteristics of zeolites were determined. The compaction test results showed that maximum dry unit weight (γ(dmax)) of fine zeolite was greater than that of granular zeolites. The γ(dmax) of compacted zeolites was between 1.01 and 1.17 Mg m(-3) and optimum water content (w(opt)) was between 38% and 53%. Regardless of zeolite particle size, compacted zeolites had low γ(dmax) and high w(opt) when compared with compacted natural soils. Then, hydraulic conductivity tests were run on compacted zeolites. The hydraulic conductivity values were within the range of 2.0 × 10(-3) cm s(-1) to 1.1 × 10(-7) cm s(-1). Hydraulic conductivity of all compacted zeolites decreased almost 50 times as the water content increased. It is noteworthy that hydraulic conductivity of compacted zeolite was strongly dependent on the zeolite particle size. The hydraulic conductivity decreased almost three orders of magnitude up to 39% fine content; then, it remained almost unchanged beyond 39%. Only one report was found in the literature on the hydraulic conductivity of compacted zeolite, which is in agreement with the findings of this study.

  8. Proton pump inhibitors

    Science.gov (United States)

    Proton pump inhibitors (PPIs) are medicines that work by reducing the amount of stomach acid made by ... Proton pump inhibitors are used to: Relieve symptoms of acid reflux, or gastroesophageal reflux disease (GERD). This ...

  9. Pumping tests in heterogeneous aquifers: An analytical study of what can be obtained from their interpretation using Jacob's Method

    Science.gov (United States)

    SáNchez-Vila, Xavier; Meier, Peter M.; Carrera, Jesús

    1999-04-01

    Interpretation of pumping tests to estimate hydraulic parameter values is typically based on the assumption of aquifer homogeneity. The applicability of the traditional methods of interpretation in real aquifers can be questioned, since the evaluation of the drawdown curves observed at different locations in a single test may not result in one consistent set of hydraulic parameters. Thus most hydrogeologists tend to look at estimated transmissivities (T) as some average property of the medium, while estimated storativities (S) are disregarded in some cases, particularly when they are obtained from data measured at the pumping well. An analytical study of drawdown under radially convergent flow toward a single point in heterogeneous aquifers shows that large time drawdown values form a straight line on a drawdown versus log time plot. Jacob's method consists of obtaining estimates for T and S from the slope and intercept of this line. We find that even in a heterogeneous field, these estimates provide valuable information about the aquifer. Estimated T values for different observation points tend to converge to a single value, which corresponds to the effective T derived under parallel flow conditions. Estimated storativities, however, display higher variability, but the geometric mean of the Sest values can be used as an unbiased estimator of the actual S. Thus it appears that although Jacob's method was originally derived for homogeneous media, it can provide valuable information in real aquifers.

  10. "GRAY-BOX" MODELING METHOD AND PARAMETERS IDENTIFICATION FOR LARGE-SCALE HYDRAULIC SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Modeling and digital simulation is an effective method to analyze the dynamic characteristics of hydraulic system. It is difficult to determine some performance parameters in the hydraulic system by means of currently used modeling methods. The "gray-box" modeling method for large-scale hydraulic system is introduced. The principle of the method, the submodels of some components and the parameters identification of components or subsystem are researched.

  11. Nanocoatings for High-Efficiency Industrial Hydraulic and Tooling Systems

    Energy Technology Data Exchange (ETDEWEB)

    Clifton B. Higdon III

    2011-01-07

    Industrial manufacturing in the U.S. accounts for roughly one third of the 98 quadrillion Btu total energy consumption. Motor system losses amount to 1.3 quadrillion Btu, which represents the largest proportional loss of any end-use category, while pumps alone represent over 574 trillion BTU (TBTU) of energy loss each year. The efficiency of machines with moving components is a function of the amount of energy lost to heat because of friction between contacting surfaces. The friction between these interfaces also contributes to downtime and the loss of productivity through component wear and subsequent repair. The production of new replacement parts requires additional energy. Among efforts to reduce energy losses, wear-resistant, low-friction coatings on rotating and sliding components offer a promising approach that is fully compatible with existing equipment and processes. In addition to lubrication, one of the most desirable solutions is to apply a protective coating or surface treatment to rotating or sliding components to reduce their friction coefficients, thereby leading to reduced wear. Historically, a number of materials such as diamond-like carbon (DLC), titanium nitride (TiN), titanium aluminum nitride (TiAlN), and tungsten carbide (WC) have been examined as tribological coatings. The primary objective of this project was the development of a variety of thin film nanocoatings, derived from the AlMgB14 system, with a focus on reducing wear and friction in both industrial hydraulics and cutting tool applications. Proof-of-concept studies leading up to this project had shown that the constituent phases, AlMgB14 and TiB2, were capable of producing low-friction coatings by pulsed laser deposition. These coatings combine high hardness with a low friction coefficient, and were shown to substantially reduce wear in laboratory tribology tests. Selection of the two applications was based largely on the concept of improved mechanical interface efficiencies for

  12. Decoupled CFD-based optimization of efficiency and cavitation performance of a double-suction pump

    Science.gov (United States)

    Škerlavaj, A.; Morgut, M.; Jošt, D.; Nobile, E.

    2017-04-01

    In this study the impeller geometry of a double-suction pump ensuring the best performances in terms of hydraulic efficiency and reluctance of cavitation is determined using an optimization strategy, which was driven by means of the modeFRONTIER optimization platform. The different impeller shapes (designs) are modified according to the optimization parameters and tested with a computational fluid dynamics (CFD) software, namely ANSYS CFX. The simulations are performed using a decoupled approach, where only the impeller domain region is numerically investigated for computational convenience. The flow losses in the volute are estimated on the base of the velocity distribution at the impeller outlet. The best designs are then validated considering the computationally more expensive full geometry CFD model. The overall results show that the proposed approach is suitable for quick impeller shape optimization.

  13. Parameter Design for the Energy-Regeneration System of Series Hydraulic-Hybrid Bus

    Directory of Open Access Journals (Sweden)

    SONG Yunpu

    2012-10-01

    Full Text Available This paper simplifies the energy recovery process in the series hydraulic hybrid bus’ energy regeneration system into a process in which the main axle’s moment of inertia drives the secondary element variable delivery pump/motor and brings hydraulic oil from the oil tank to the accumulator. This process enables braking of the vehicle and also allows recovery of energy to the accumulator. Based on the flow equation for the secondary element variable delivery pump/motor and the torque equilibrium equation for its axle, the force equilibrium equation for vehicle braking and the pressure variation and flow continuity equations for the accumulator, simulation studies are conducted to analyze the effects of various system parameters, such as accumulator capacity, displacement of the secondary element variable delivery pump/motor, initial operating pressure of the system, etc. on system performance during regenerative braking.  

  14. Hydraulic Actuators with Autonomous Hydraulic Supply for the Mainline Aircrafts

    Directory of Open Access Journals (Sweden)

    I. S. Shumilov

    2014-01-01

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

  15. Hydraulic conductivity of organomodified soil

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, R.B.; Grant, J.M.; Voice, T.C.; Rakhshandehroo, G.; Xu, S.; Boyd, S.A. [Michigan State Univ., East Lansing, MI (United States)

    1995-11-01

    The effects of organomodification on soil hydraulic conductivity were investigated. Hydraulic conductivity and porosity of treated and untreated samples of a sandy loam were measured as a function of effective stress. Batch treatment with hexadecyltrimethyl ammonium (HDTMA) and dry packing produced organomodified samples that were 79% less conducive than untreated samples prior to loading. Treated samples lost less hydraulic conductivity as a result of loading than untreated samples so that treated samples had higher conductivity at high loads. Observed differences in conductivity are explained in terms of the role of the treated and untreated clay in controlling initial effective pore size and its change during consolidation.

  16. Pump for Saturated Liquids

    Science.gov (United States)

    Elliott, D. G.

    1986-01-01

    Boiling liquids pumped by device based on proven components. Expanding saturated liquid in nozzle and diverting its phases along separate paths in liquid/vapor separator raises pressure of liquid. Liquid cooled in process. Pump makes it unnecessary to pressurize cryogenic liquids in order to pump them. Problems of introducing noncondensable pressurizing gas avoided.

  17. The effect of balance holes to centrifugal pump performance

    Science.gov (United States)

    Babayigit, O.; Ozgoren, M.; Aksoy, M. H.; Kocaaslan, O.

    2017-07-01

    The aim of this study is to analyze of a centrifugal pump with and without balance holes by using ANSYS-Fluent software. The pump used in the study is a commercial centrifugal pump consisting of two stages that is a model of Sempa Pump Company. Firstly, models of impeller, diffuser, suction and discharge sections of the centrifugal pump were separately drawn using Ansys and Solidworks software. Later, grid structures were generated on the flow volume of the pump. Turbulent flow volume was numerically solved by realizable k-є turbulence model. The flow analyses were focused on the centrifugal pump performance and the flow characteristics under different operational conditions with/without balance holes. Distributions of flow characteristics such as velocity and pressure distributions in the flow volume were also determined, numerically. The results of Computational Fluid Dynamics (CFD) with/without balance holes for the pump head and hydraulic efficiency on the design flow rate of 80 m3/h were found to be 81.5/91.3 m and 51.9/65.3%, respectively.

  18. Numerical simulation of the two-phase flows in a hydraulic coupling by solving VOF model

    Science.gov (United States)

    Luo, Y.; Zuo, Z. G.; Liu, S. H.; Fan, H. G.; Zhuge, W. L.

    2013-12-01

    The flow in a partially filled hydraulic coupling is essentially a gas-liquid two-phase flow, in which the distribution of two phases has significant influence on its characteristics. The interfaces between the air and the liquid, and the circulating flows inside the hydraulic coupling can be simulated by solving the VOF two-phase model. In this paper, PISO algorithm and RNG k-ɛ turbulence model were employed to simulate the phase distribution and the flow field in a hydraulic coupling with 80% liquid fill. The results indicate that the flow forms a circulating movement on the torus section with decreasing speed ratio. In the pump impeller, the air phase mostly accumulates on the suction side of the blades, while liquid on the pressure side; in turbine runner, air locates in the middle of the flow passage. Flow separations appear near the blades and the enclosing boundaries of the hydraulic coupling.

  19. Assessing Hydraulic Connections Across Structural Blocks, Pahute Mesa, Nevada—Detecting Distant Drawdowns

    Science.gov (United States)

    Garcia, C.; Fenelon, J. M.; Halford, K. J.; Sweetkind, D. S.

    2010-12-01

    Groundwater beneath Pahute Mesa flows through a complexly layered sequence of volcanic-rock aquifers and confining units that have been faulted into distinct structural blocks. Hydraulic properties of the rocks and structures in this aquifer system control radionuclide migration away from areas of underground testing. Detecting drawdowns in observation wells that penetrate a structural block different from the structural block intersected by the pumping well provides irrefutable evidence of a hydraulic connection. However, detecting these pumping-induced changes in water-level records typical of Pahute Mesa can be problematic because environmental noise frequently exceeds the pumping signal. Therefore, inherent noise must be removed from the water-level record systematically before pumping-induced drawdown and subsequent recovery can be quantified and analyzed. Successful applications of this approach on Pahute Mesa are illustrated using water-level records acquired during selected periods of recent drilling, development, testing, and pumping. Continuous monitoring of water level and air pressure changes in two dozen wells reveal moderate and high frequency stresses such as barometric pressure and earth tides along with gradual water-level changes induced by well drilling, development, and testing. At distances of nearly 4 km from pumping stresses, drawdown and recovery responses of less than 0.02 m can be detected using a synthetic water-level analysis. Synthetic water-levels are the summation of barometric, tidal, and pumping responses and water levels from background wells that are fit to measured water levels in remote observation wells. Pumping responses are simulated by superposition of Theis solutions. Differences between synthetic and measured water levels are minimized by adjusting the amplitude and phase of non-pumping components, while the transmissivity and storage coefficient are estimated from the pumping responses.

  20. Hydraulic Tomography to Characterization of Heterogeneity of Unconfined Aquifers

    Science.gov (United States)

    Zhu, J.; Yeh, T. J.

    2008-12-01

    Analytical models are the most widely used methods for analyzing pumping tests in unconfined aquifers. However, one major group analytical models assume instantaneous and complete drainage at the water table and therefore are inadequate to account for gradual drainage of water from the vadose zone due to pumping; the other major group analytical models use an exponential function of drawdown at the water table to account for gradual drainage and are subsequently limited to represent the highly non-linear flow in the vadose zone. Moreover, both models assume aquifer homogeneity while the natural aquifers are inherently heterogeneous. Recently emerged Hydraulic tomography (HT) is a cost-effective method for mapping spatial distribution of aquifer hydraulic properties. HT takes advantage of the power of numerical models and fuses information from multiple cross-hole tests conducted at different locations to image aquifers in great details. In this study, we apply HT concept to unconfined aquifers. To accurately simulate the flow behavior due to a HT survey in an unconfined aquifer, a fully three dimensional variably saturated flow model based on mixed form of Richards equation is used. Pressure responses in both saturated and unsaturated zones are used to estimate spatial variations of hydraulic conductivity, specific storage, and soil water constitutive model parameters through a sequential successive linear estimator. A systematic approach that uses wavelet analysis, least-square method, and fuzzy similarity compassion is applied for data denoising, statistic inputs, convergence, and performance assessment. A cross-correlation is also performed to investigate the relation between pressure change and different parameters. The HT method for unconfined aquifers is tested in a synthetic aquifer. The tests show that the proposed HT method effectively maps heterogeneity of the unconfined aquifer and predicts the vadose zone responses due to a pumping test more accurately

  1. Miniature Scroll Pumps Fabricated by LIGA

    Science.gov (United States)

    Wiberg, Dean; Shcheglov, Kirill; White, Victor; Bae, Sam

    2009-01-01

    Miniature scroll pumps have been proposed as roughing pumps (low - vacuum pumps) for miniature scientific instruments (e.g., portable mass spectrometers and gas analyzers) that depend on vacuum. The larger scroll pumps used as roughing pumps in some older vacuum systems are fabricated by conventional machining. Typically, such an older scroll pump includes (1) an electric motor with an eccentric shaft to generate orbital motion of a scroll and (2) conventional bearings to restrict the orbital motion to a circle. The proposed miniature scroll pumps would differ from the prior, larger ones in both design and fabrication. A miniature scroll pump would include two scrolls: one mounted on a stationary baseplate and one on a flexure stage (see figure). An electromagnetic actuator in the form of two pairs of voice coils in a push-pull configuration would make the flexure stage move in the desired circular orbit. The capacitance between the scrolls would be monitored to provide position (gap) feedback to a control system that would adjust the drive signals applied to the voice coils to maintain the circular orbit as needed for precise sealing of the scrolls. To minimize power consumption and maximize precision of control, the flexure stage would be driven at the frequency of its mechanical resonance. The miniaturization of these pumps would entail both operational and manufacturing tolerances of pump components. In addition, the vibrations of conventional motors and ball bearings exceed these tight tolerances by an order of magnitude. Therefore, the proposed pumps would be fabricated by the microfabrication method known by the German acronym LIGA ( lithographie, galvanoformung, abformung, which means lithography, electroforming, molding) because LIGA has been shown to be capable of providing the required tolerances at large aspect ratios.

  2. HYDRAULICS, ATHENS COUNTY, OHIO, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulic data include spatial datasets and data tables necessary for documenting the hydrologic procedures for estimating flood discharges for a flood insurance...

  3. HYDRAULICS, JACKSON COUNTY, KENTUCKY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulic data include spatial datasets and data tables necessary for documenting the hydrologic procedures for estimating flood discharges for a flood insurance...

  4. HYDRAULICS, MADISON COUNTY, ALABAMA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — This Hydraulic data was reviewed and approved by FEMA during the initial MT-2 processing. Recent developments in digital terrain and geospatial database management...

  5. HYDRAULICS, HAMPDEN COUNTY, MA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulic data in this submittal include spatial datasets and model outputs necessary for computation of the 1-percent flooding extent. The minimum requirement for...

  6. 14 CFR 29.1435 - Hydraulic systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 29.1435 Section 29.1435... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each element of the hydraulic system...

  7. 14 CFR 23.1435 - Hydraulic systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 23.1435 Section 23.1435... § 23.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each hydraulic system and its elements must withstand, without yielding, the structural loads expected...

  8. 46 CFR 28.405 - Hydraulic equipment.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Hydraulic equipment. 28.405 Section 28.405 Shipping... Operate With More Than 16 Individuals on Board § 28.405 Hydraulic equipment. (a) Each hydraulic system... than four times the system maximum operating pressure. (c) Each hydraulic system must be equipped...

  9. Developed hydraulic simulation model for water pipeline networks

    Directory of Open Access Journals (Sweden)

    A. Ayad

    2013-03-01

    Full Text Available A numerical method that uses linear graph theory is presented for both steady state, and extended period simulation in a pipe network including its hydraulic components (pumps, valves, junctions, etc.. The developed model is based on the Extended Linear Graph Theory (ELGT technique. This technique is modified to include new network components such as flow control valves and tanks. The technique also expanded for extended period simulation (EPS. A newly modified method for the calculation of updated flows improving the convergence rate is being introduced. Both benchmarks, ad Actual networks are analyzed to check the reliability of the proposed method. The results reveal the finer performance of the proposed method.

  10. Design Rules for High Damping in Mobile Hydraulic Systems

    OpenAIRE

    Axin, Mikael; Krus, Petter

    2013-01-01

    This paper analyses the damping in pressure compensated closed centre mobile working hydraulic systems. Both rotational and linear loads are covered and the analysis applies to any type of pump controller. Only the outlet orifice in the directional valve will provide damping to a pressure compensated system. Design rules are proposed for how the system should be dimensioned in order to obtain a high damping. The volumes on each side of the load have a high impact on the damping. In case of a ...

  11. Advanced Performance Hydraulic Wind Energy

    Science.gov (United States)

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

    2013-01-01

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

  12. The Importance of Computational Modeling of Large Pumping Stations

    Directory of Open Access Journals (Sweden)

    S. M. Bozh'eva

    2015-01-01

    Full Text Available The article presents main design and structure principles of pumping stations. It specifies basic requirements for the favorable hydraulic operation conditions of the pumping units. The article also describes the designing cases, when computational modeling is necessary to analyse activity of pumping station and provide its reliable operation. A specific example of the large pumping station with submersible pumps describes the process of computational modeling of its operation. As the object of simulation was selected the underground pumping station with a diameter of 26 m and a depth of 13 m, divided into two independent branches, equipped with 8 submersible pumps. The objective of this work was to evaluate the effectiveness of the design solution by CFD methods, to analyze the design of the inlet chamber, to identify possible difficulties with the operation of the facility. In details are described the structure of the considered pumping station and applied computational models of physical processes. The article gives the detailed formulation of the task of simulation and the methods of its solving and presents the initial and boundary conditions. It describes the basic operation modes of the pumping station. The obtained results were presented as the flow patterns for each operation mode with detailed explanations. Data obtained as a result of CFD, prove the correctness of the general design solutions of the project. The submersible pump operation at the minimum water level was verified, was confirmed a lack of vortex formation as well as were proposed measures to improve the operating conditions of the facility. In the inlet chamber there are shown the stagnant zones, requiring separate schedule of cleaning. The measure against floating debris and foam was proposed. It justifies the use of computational modeling (CFD for the verifying and adjusting of the projects of large pumping stations as a much more precise tool that takes into account

  13. Combining 3D Hydraulic Tomography with Tracer Tests for Improved Transport Characterization.

    Science.gov (United States)

    Sanchez-León, E; Leven, C; Haslauer, C P; Cirpka, O A

    2016-07-01

    Hydraulic tomography (HT) is a method for resolving the spatial distribution of hydraulic parameters to some extent, but many details important for solute transport usually remain unresolved. We present a methodology to improve solute transport predictions by combining data from HT with the breakthrough curve (BTC) of a single forced-gradient tracer test. We estimated the three dimensional (3D) hydraulic-conductivity field in an alluvial aquifer by inverting tomographic pumping tests performed at the Hydrogeological Research Site Lauswiesen close to Tübingen, Germany, using a regularized pilot-point method. We compared the estimated parameter field to available profiles of hydraulic-conductivity variations from direct-push injection logging (DPIL), and validated the hydraulic-conductivity field with hydraulic-head measurements of tests not used in the inversion. After validation, spatially uniform parameters for dual-domain transport were estimated by fitting tracer data collected during a forced-gradient tracer test. The dual-domain assumption was used to parameterize effects of the unresolved heterogeneity of the aquifer and deemed necessary to fit the shape of the BTC using reasonable parameter values. The estimated hydraulic-conductivity field and transport parameters were subsequently used to successfully predict a second independent tracer test. Our work provides an efficient and practical approach to predict solute transport in heterogeneous aquifers without performing elaborate field tracer tests with a tomographic layout.

  14. Education for hydraulics and pneumatics in Nihon University; Nihon Daigaku ni okeru yukuatsu kyoiku

    Energy Technology Data Exchange (ETDEWEB)

    Ouchi, M. [Nihon Univ., Chiba (Japan). Coll. of Industrial Technology

    2000-03-15

    Described herein is education of hydraulics and pneumatics in Nihon University. Department of Mechanical Engineering of Faculty of Production Engineering has been holding up the educational aims of bringing up engineers and researchers who have ability and intelligence to cope with internationalization and contribute to society, and of bringing about creativity, among others. Control equipment is an optional subject for the sophomore class in the second semester, and is centered by mechatronics, including hydraulic and pneumatic control systems and equipment. The related subjects include fluid dynamics, control engineering, system controlling, hydraulic machines, robotics and automobile engineering. The drill course includes disassembling and assembling gear pumps, drills on pneumatic devices, system behavior and mechatronics, experiments on fan and hydraulic control circuits and on servo mechanisms, and machinery designs and drawings. Seminars are led by full-time or part-time lecturers for the themes related to hydraulic power. Many students are interested in hydraulic and pneumatic themes for their graduation theses, because of their relations with control, environments, energy saving and so on. We are now in the age of composite technologies, and hydraulic power basics are prerequisite for engineers, and important for education of students. (NEDO)

  15. A quantitative analysis of hydraulic interaction processes in stream-aquifer systems.

    Science.gov (United States)

    Wang, Wenke; Dai, Zhenxue; Zhao, Yaqian; Li, Junting; Duan, Lei; Wang, Zhoufeng; Zhu, Lin

    2016-01-28

    The hydraulic relationship between the stream and aquifer can be altered from hydraulic connection to disconnection when the pumping rate exceeds the maximum seepage flux of the streambed. This study proposes to quantitatively analyze the physical processes of stream-aquifer systems from connection to disconnection. A free water table equation is adopted to clarify under what conditions a stream starts to separate hydraulically from an aquifer. Both the theoretical analysis and laboratory tests have demonstrated that the hydraulic connectedness of the stream-aquifer system can reach a critical disconnection state when the horizontal hydraulic gradient at the free water surface is equal to zero and the vertical is equal to 1. A boundary-value problem for movement of the critical point of disconnection is established for an analytical solution of the inverted water table movement beneath the stream. The result indicates that the maximum distance or thickness of the inverted water table is equal to the water depth in the stream, and at a steady state of disconnection, the maximum hydraulic gradient at the streambed center is 2. This study helps us to understand the hydraulic phenomena of water flow near streams and accurately assess surface water and groundwater resources.

  16. Fundamental characteristics of oil hydraulic servo system; Yuatsu servo kei no kihonteki tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, K. [Musashi Instsitute of Technology, Tokyo (Japan)

    1999-05-15

    Since a hydraulic servo generates a great force very quickly upon receiving a small force or electric power, it is widely used in machine tools, construction machinery, and vehicles. The basics are that a high pressure fluid generated by a hydraulic pump is controlled by a valve and forwarded to a hydraulic cylinder or rotary hydraulic motor for the generation of a parallel motion or rotation. For the control of the valve, there are the mechanical-hydraulic servo mechanism in which the valve is operated by mechanical linkage and the electrical-hydraulic servo system in which the valve is driven by electric signals. It is difficult to perform sophisticated control such as optimum control by use of the mechanical method while the electrical method may be applied to such sophisticated control. In the former, a hydraulic servo system is constructed using mechanical feedback. It is simpler and more reliable than the other, and is used for the control of aircraft wings and for the steering of ships and vehicles. Using the latter, electric signals low in power are amplified in a servo amplifier before being sent to the servo valve. For the driving of the spool in a servo valve, the nozzle and flapper system is widely in use. (NEDO)

  17. Static pressure recovery analysis in the vane island diffuser of a centrifugal pump

    Energy Technology Data Exchange (ETDEWEB)

    Si, Qiaorui [National Research Center of Pumps, Jiangsu University, Zhenjiang (China); Dupont, Patrick; Bayeul-Laine, Annie-Claude; Dazin, Antoine; Roussette, Olivier; Bois, Gerard [LML, UMR CNRS 8107 Ecole Centrale de Lille, Lille (France)

    2016-02-15

    The overall performance of a vane-island type diffuser of a centrifugal pump model was obtained by means of directional probe traverses. These measurements were performed in an air model of a real hydraulic pump for five volume flow rates. Directional probe traverses are performed with a classical three-hole probe to cover most of the complete inlet section of the diffuser from hub to shroud and from pressure to suction side. Existing Particle image velocimetry (PIV) measurement results are also used to compare probe measurement results between the inlet and outlet throats of vane island diffuser at mid-span. Some assistance from already existing unsteady calculation, including leakage effects, is used to evaluate the numerical approach capability and to correctly define the mean initial conditions at impeller's outlet section. Pressure recovery and the measured total pressure loss levels inside this particular vane diffuser geometry are then calculated. Detailed analysis of the flow structure at the inlet section of the vane island diffuser is presented to focus on pressure evolution inside the entire diffuser section for different flow rates. The combined effects of incidence angle and blockage distributions along hub to shroud direction are found to play an important role on loss distribution in such a diffuser.

  18. Nonlinear Non-convex Optimization of Hydraulic Networks

    DEFF Research Database (Denmark)

    Tahavori, Maryamsadat; Kallesøe, Carsten; Leth, John-Josef

    2013-01-01

    Pressure management in water supply systems is an effective way to reduce the leakage in a system. In this paper, the pressure management and the reduction of power consumption of a water supply system is formulated as an optimization problem. The problem is to minimize the power consumption...... in pumps and also to regulate the pressure at the end-user valves to a desired value. The optimization problem which is solved is a nonlinear and non-convex optimization. The barrier method is used to solve this problem. The modeling framework and the optimization technique which are used are general....... They can be used for a general hydraulic networks to optimize the leakage and energy consumption and to satisfy the demands at the end-users. The results in this paper show that the power consumption of the pumps is reduced....

  19. Optimization of Classical Hydraulic Engine Mounts Based on RMS Method

    Directory of Open Access Journals (Sweden)

    J. Christopherson

    2005-01-01

    Full Text Available Based on RMS averaging of the frequency response functions of the absolute acceleration and relative displacement transmissibility, optimal parameters describing the hydraulic engine mount are determined to explain the internal mount geometry. More specifically, it is shown that a line of minima exists to define a relationship between the absolute acceleration and relative displacement transmissibility of a sprung mass using a hydraulic mount as a means of suspension. This line of minima is used to determine several optimal systems developed on the basis of different clearance requirements, hence different relative displacement requirements, and compare them by means of their respective acceleration and displacement transmissibility functions. In addition, the transient response of the mount to a step input is also investigated to show the effects of the optimization upon the time domain response of the hydraulic mount.

  20. Dynamic damper pressure fluctuation in the pumping systems

    Directory of Open Access Journals (Sweden)

    O.V. Korolyov

    2016-05-01

    Full Text Available Inertial part of any devices and equipment (e.g., pumps, hung or mounted on the resilient frame and being under the influence of the disturbing force that works at a constant frequency, may be subject to fluctuations, especially near of the resonance area. For elimination these fluctuations, you can resort to the use of a dynamic damper. Aim: The aim of the work is an analytical study of various dynamic dampers to reduce pressure fluctuation problems in pumping systems. Materials and Methods: A comparative analysis of efficiency of functioning was carried out for two types of dynamic dampers - hydraulic and mechanical. Results: The technique for calculating of dynamic damper of fluid pressure fluctuations in the hydraulic and mechanical pumps is presented. Algorithms of calculations are reported to engineering applications and implemented in the production process. The calculations show that the use of dynamic mechanical dampers is expedient at high frequency pumps, and, with increasing frequency of the pump by 6 times, winning in the dimensions of the damper in 3.5 times.

  1. Evaluation of the hydraulic and biological performance of the portable floating fish collector at Cougar Reservoir and Dam, Oregon, 2014

    Science.gov (United States)

    Beeman, John W.; Evans, Scott D.; Haner, Philip V.; Hansel, Hal C.; Hansen, Amy C.; Hansen, Gabriel S.; Hatton, Tyson W.; Sprando, Jamie M.; Smith, Collin D.; Adams, Noah S.

    2016-01-12

    The biological and hydraulic performance of a new portable floating fish collector (PFFC) located in a cul-de-sac within the forebay of Cougar Dam, Oregon, was evaluated during 2014. The purpose of the PFFC was to explore surface collection as a means to capture juvenile salmonids at one or more sites using a small, cost-effective, pilot-scale device. The PFFC used internal pumps to draw attraction flow over an inclined plane about 3 meters (m) deep, through a flume at a design velocity of as much as 6 feet per second (ft/s), and to empty a small amount of water and any entrained fish into a collection box. Performance of the PFFC was evaluated at 64 cubic feet per second (ft3/s) (Low) and 109 ft3/s (High) inflow rates alternated using a randomized-block schedule from May 27 to December 16, 2014. The evaluation of the biological performance was based on trap catch; behaviors, locations, and collection of juvenile Chinook salmon (Oncorhynchus tshawytscha) tagged with acoustic transmitters plus passive integrated transponder (PIT) tags; collection of juvenile Chinook salmon implanted with only PIT tags; and untagged fish monitored near and within the PFFC using acoustic cameras. The evaluation of hydraulic performance was based on measurements of water velocity and direction of flow in the PFFC.

  2. Heat pumps in agricultural uses. Factsheet

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, R.D.

    1986-04-01

    This paper provides an elementary introduction to heat pumps and their potential for use in Ontario agricultural applications, taking into account local climatic conditions which mean high heating loads and small cooling loads. A heat pump's ability to remove heat from a variety of sources and boost this heat to a useable temperature enables such farm uses as recovery of heat from exhaust air in livestock barns, greenhouse heating using ground water, and heat extraction from manure. Basic types of heat pumps are evaluated and compared, and their costs are estimated.

  3. Prediction of spatially variable unsaturated hydraulic conductivity using scaled particle-size distribution functions

    NARCIS (Netherlands)

    Nasta, P.; Romano, N.; Assouline, S; Vrugt, J.A.; Hopmans, J.W.

    2013-01-01

    Simultaneous scaling of soil water retention and hydraulic conductivity functions provides an effective means to characterize the heterogeneity and spatial variability of soil hydraulic properties in a given study area. The statistical significance of this approach largely depends on the number of s

  4. Nonlinear, Adaptive and Fault-tolerant Control for Electro-hydraulic Servo Systems

    DEFF Research Database (Denmark)

    Choux, Martin

    Fluid power systems have been in use since 1795 with the rst hydraulic press patented by Joseph Bramah and today form the basis of many industries. Electro hydraulic servo systems are uid power systems controlled in closed-loop. They transform reference input signals into a set of movements...... in hydraulic actuators (cylinders or motors) by the means of hydraulic uid under pressure. With the development of computing power and control techniques during the last few decades, they are used increasingly in many industrial elds which require high actuation forces within limited space. However, despite...... numerous attractive properties, hydraulic systems are always subject to potential leakages in their components, friction variation in their hydraulic actuators and deciency in their sensors. These violations of normal behaviour reduce the system performances and can lead to system failure...

  5. From the Kinetic Energy Recovery System to the Thermo-Hydraulic Hybrid Motor Vehicle

    Science.gov (United States)

    Cristescu, Corneliu; Drumea, Petrin; Guta, Dragos; Dumitrescu, Catalin

    2011-12-01

    The paper presents some theoretical and experimental results obtained by the Hydraulics and Pneumatics Research Institute INOE 2000-IHP with its partners, regarding the creating of one hydraulic system able to recovering the kinetic energy of the motor vehicles, in the braking phases, and use this recovered energy in the starting and accelerating phases. Also, in the article is presented a testing stand, which was especially designed for testing the hydraulic system for recovery the kinetic energy. Through mounting of the kinetic energy recovering hydraulic system, on one motor vehicle, this vehicle became a thermo-hydraulic hybrid vehicle. Therefore, the dynamic behavior was analyzed for the whole hybrid motor vehicle, which includes the energy recovery system. The theoretical and experimental results demonstrate the possible performances of the hybrid vehicle and that the kinetic energy recovery hydraulic systems are good means to increase energy efficiency of the road motor vehicles and to decrease of the fuel consumption.

  6. Investigation of noise sources and propagation in external gear pumps

    Science.gov (United States)

    Opperwall, Timothy J.

    Oil hydraulics is widely accepted as the best technology for transmitting power in many engineering applications due to its advantages in power density, control, layout flexibility, and efficiency. Due to these advantages, hydraulic systems are present in many different applications including construction, agriculture, aerospace, automotive, forestry, medical, and manufacturing, just to identify a few. Many of these applications involve the systems in close proximity to human operators and passengers where noise is one of the main constraints to the acceptance and spread of this technology. As a key component in power transfer, displacement machines can be major sources of noise in hydraulic systems. Thus, investigation into the sources of noise and discovering strategies to reduce noise is a key part of applying fluid power systems to a wider range of applications, as well as improving the performance of current hydraulic systems. The present research aims to leverage previous efforts and develop new models and experimental techniques in the topic of noise generation caused by hydrostatic units. This requires challenging and surpassing current accepted methods in the understanding of noise in fluid power systems. This research seeks to expand on the previous experimental and modeling efforts by directly considering the effect that system and component design changes apply on the total sound power and the sound frequency components emitted from displacement machines and the attached lines. The case of external gear pumps is taken as reference for a new model to understand the generation and transmission of noise from the sources out to the environment. The lumped parameter model HYGESim (HYdraulic GEar machine Simulator) was expanded to investigate the dynamic forces on the solid bodies caused by the pump operation and to predict interactions with the attached system. Vibration and sound radiation were then predicted using a combined finite element and boundary

  7. Geostatistical Estimations of Regional Hydraulic Conductivity Fields

    Science.gov (United States)

    Patriarche, D.; Castro, M. C.; Goovaerts, P.

    2004-12-01

    Direct and indirect measurements of hydraulic conductivity (K) are commonly performed, providing information on the magnitude of this parameter at the local scale (tens of centimeters to hundreds of meters) and at shallow depths. By contrast, field information on hydraulic conductivities at regional scales of tens to hundreds of kilometers and at greater depths is relatively scarce. Geostatistical methods allow for sparsely sampled observations of a variable (primary information) to be complemented by a more densely sampled secondary attribute. Geostatistical estimations of the hydraulic conductivity field in the Carrizo aquifer, a major groundwater flow system extending along Texas, are performed using available primary (e.g., transmissivity, hydraulic conductivity) and secondary (specific capacity) information, for depths up to 2.2 km, and over three regional domains of increasing extent: 1) the domain corresponding to a three-dimensional groundwater flow model previously built (model domain); 2) the area corresponding to the ten counties encompassing the model domain (County domain), and; 3) the full extension of the Carrizo aquifer within Texas (Texas domain). Two different approaches are used: 1) an indirect approach are transmissivity (T) is estimated first and (K) is retrieved through division of the T estimate by the screening length of the wells, and; 2) a direct approach where K data are kriged directly. Prediction performances of the tested geostatistical procedures (kriging combined with linear regression, kriging with known local means, kriging of residuals, and cokriging) are evaluated through cross validation for both log-transformed variables and back-transformed ones. For the indirect approach, kriging of log T residuals yields the best estimates for both log-transformed and back-transformed variables in the model domain. For larger regional scales (County and Texas domains), cokriging performs generally better than univariate kriging procedures

  8. Commercial absorption heat pumps (design, performance)

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R. (Padua Univ. (Italy). Ist. di Fisica Tecnica)

    1986-04-01

    After a historical review of the development of absorption heat pumps, a critical analysis is presented of the design and operation of typical 25-40 kW, commercially available heat pumps. This engineering critique is followed by an analysis of the performance of 25 kW plant thoroughly tested to provide, by means of statistically significant data, a reliable assessment of the coefficient of performance and capacity in function of the cold source temperature for different return temperatures.

  9. Failure Analysis of a Water Supply Pumping Pipeline System

    Directory of Open Access Journals (Sweden)

    Oscar Pozos-Estrada

    2016-09-01

    Full Text Available This paper describes the most important results of a theoretical, experimental and in situ investigation developed in connection with a water supply pumping pipeline failure. This incident occurred after power failure of the pumping system that caused the burst of a prestressed concrete cylinder pipe (PCCP. Subsequently, numerous hydraulic transient simulations for different scenarios and various air pockets combinations were carried out in order to fully validate the diagnostic. As a result, it was determined that small air pocket volumes located along the pipeline profile were recognized as the direct cause of the PCCP rupture. Further, a detail survey of the pipeline was performed using a combination of non-destructive technologies in order to determine if immediate intervention was required to replace PCC pipes. In addition, a hydraulic model was employed to analyze the behavior of air pockets located at high points of the pipeline.

  10. Design of a centrifugal blood pump: Heart Turcica Centrifugal.

    Science.gov (United States)

    Demir, Onur; Biyikli, Emre; Lazoglu, Ismail; Kucukaksu, Suha

    2011-07-01

    A prototype of a new implantable centrifugal blood pump system named Heart Turcica Centrifugal (HTC) was developed as a left ventricular assist device (LVAD) for the treatment of end-stage cardiac failure. In the development of HTC, effects of blade height and volute tongue profiles on the hydraulic and hemolytic performances of the pump were investigated. As a result, the prototype was manufactured using the best blade height and volute tongue profiles. Performance of the prototype model was experimentally evaluated in a closed-loop flow system using water as the medium. The hydraulic performance requirement of an LVAD (5 L/min flow rate against a pressure difference of 100 mm Hg) was attained at 2800 rpm rotational speed.

  11. Prediction of rotating stall and cavitation inception in pump turbines

    Energy Technology Data Exchange (ETDEWEB)

    Anciger, D; Jung, A; Aschenbrenner, T, E-mail: Danijel.Anciger@voith.co [Voith Hydro Holding GmbH and Co. KG Alexanderstr. 11, 89522 Heidenheim (Germany)

    2010-08-15

    The current development of modern pump storage plants aims towards a higher flexibility in operation, an extended operation range of the hydraulic machine, especially in the pumping mode, and a higher reliability. A major design target for state-of-the-art reversible Francis-type pump turbines is to find an optimal balance between pumping and generating performance. The pumping requirements are the crucial design drivers, since, even if the turbine mode performance is world class, the success of a project depends on the pump turbine delivering the required maximum pump head and starting reliably in pump mode. The proposed paper describes how advanced computational fluid dynamic (CFD) simulations can help the designer to evaluate his design with respect to hydraulic performance and dynamic phenomena occurring in pump turbines. A standard procedure today is to compute the flow by applying the Reynolds-averaged Navier-Stokes equations (RANS) on the steady-state flow in individual components or in multiple components which are coupled by mixing-plane interfaces (sometimes also called stage-interface). This standard approach gives fast turnaround times and is a good engineering tool. However, accuracy is limited due to necessary simplifications. Therefore methods are developed and evaluated which allow a more reliable prediction of the onset of rotating stall which is the operation limit of the pump under high heads and low flow rates. The behaviour a modern pump turbine design in this instability region is investigated in detail. Another important task in the design process is the proper prediction of cavitation phenomena in the runner. Predicting cavitating flows with multi-phase CFD computations is still a very challenging task. Some results of ongoing work in this field are presented and compared to single phase computations and results from model tests. The relevance and applicability of such computations is discussed. All the information gained from these kinds of

  12. Design of a Turbulence Generator of Medium Consistency Pulp Pumps

    OpenAIRE

    Hong Li; Haifei Zhuang; Weihao Geng

    2012-01-01

    The turbulence generator is a key component of medium consistency centrifugal pulp pumps, with functions to fluidize the medium consistency pulp and to separate gas from the liquid. Structure sizes of the generator affect the hydraulic performance. The radius and the blade laying angle are two important structural sizes of a turbulence generator. Starting with the research on the flow inside and shearing characteristics of the MC pulp, a simple mathematical model at the flow section of the sh...

  13. Application of hydraulic coupling transmission diesel engine and mud pump working group in Daqing Oilfield%液力耦合器传动柴油机-泥浆泵工作组在大庆油田的应用

    Institute of Scientific and Technical Information of China (English)

    何军军

    2016-01-01

    Mud pump plays an important role in drilling construction,and it is also a high energy consuming and easily damaged drilling equipment.%泥浆泵在钻井施工中有着举足轻重的作用,同时也是高耗能、易损坏的钻井设备。

  14. Hydraulic Equalizing Valve with Total Power Control%液压泵总功率控制的均压阀

    Institute of Scientific and Technical Information of China (English)

    杨莽; 王林

    2016-01-01

    The design and practical use of the hydraulic system, the two variable piston pump together in the same hydraulic system and to ensure consistency and to achieve the two hydraulic displacement of the total power control. The general use of two cross-pump control mode, the disadvantage is that the two hydraulic control cross consistency and total power control is poor, and it is difficult to ensure the con-sistency of the two hydraulic pumps. In this paper, by designing a pressure equalization valve to achieve the two hydraulic control. The re-sults showed that the equalizing valve can well ensure the consistency of the two hydraulic pumps and total power control.%在液压系统的设计和实际使用过程中,两台变量柱塞液压泵共同作用于同一液压系统并保证两台液压泵排量一致且要实现总功率控制.目前一般采用两台液压泵交叉控制的方式,交叉控制的缺点是两台液压泵的一致性和总功率控制效果差,且很难保证两台液压泵的一致性.该文通过设计一种均压阀,来实现两台液压泵的控制.结果表明,均压阀能够很好地保证两台液压泵的一致性和总功率控制.

  15. Multi-Temperature Heat Pump with Cascade Compressor Connection

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2017-08-01

    Full Text Available The object of the study is a multifunctional heat pump with several evaporators and condensers designed for simultaneous provision of technological processes with heat and cold. The aim of the work is the development and study of the scheme for this type of heat pumps, which ensures minimum irreversibility in the "compressor-gas coolers" chain, without the use of adjustable ejectors installed after evaporators and used as flow mixers. The obtained technical solution ensures the stabilization of the heat pump coefficient of performance (COP and prescribed thermal regimes of heat exchangers at a variable flow rate of the refrigerant. The novelty of the elaboration is inclusion a compressor of the first stage with a serially connected intermediate heat exchanger and a control valve that are located before the compressor inlet of the second stage of the heat pump, which allows to establish a rational pressure after the first stage of the compressors. A scheme is proposed for regulating the temperature at the inlet of the first stage compressors by regulating the flow through the primary circuits of the recuperative heat exchangers. The first stage compressor control system allows providing the required modes of operation of the heat pump. It is established, because of the exergetic analysis of the sections of the hydraulic circuit of heat pump located between the evaporators and gas coolers that the reduction of irreversible losses in the heat pump is ensured due to the optimal choice of the superheat value of the gas after the evaporators.

  16. Do perceptions of insulin pump usability impact attitudes toward insulin pump therapy? A pilot study of individuals with type 1 and insulin-treated type 2 diabetes.

    Science.gov (United States)

    Chamberlain, James J; Gilgen, Emily

    2015-01-01

    We assessed the impact of perceived insulin pump usability on attitudes toward insulin pump therapy in diabetic individuals currently treated with multiple daily insulin injections (MDI). This comparative, single-arm study recruited 28 adults with type 1 (n = 16) and insulin-treated type 2 diabetes (n = 12) to evaluate 2 current insulin pumps: Medtronic Revel 723 (Pump 1), Asante Snap Insulin Pump (Pump 2). Participants were randomized 1:1 to 1 of 2 assessment sequences: Pump 1 followed by Pump 2; and Pump 2 followed by Pump 1. Structured observational protocols were utilized to assess participants' ability and time required to learn/perform common tasks associated with pump setup/use. Participants used a modified version of the System Usability Scale (SUS) and investigator-developed questionnaires to rate pump usability and task difficulty; pre-post questionnaires assessed changes in attitudes toward insulin pump therapy. All participants completed the study. SUS scores showed Pump 2 to be more usable than Pump 1 on all usability attributes. Participants rated Pump 2 more positively than Pump 1, overall mean SUS scores of 5.7 versus 4.1 respectively, F(1, 52) = 32.7, P Pump 2 last, 5.3 versus 4.4 for Pump 1 last, F(1, 52) = 10.8, P Pump 2 was preferred for all tasks: manual bolus (86%), bolus calculation (71%), managing basal rates (93%), interpreting alarms (96%), transferring settings (100%), changing insulin and infusion sets (93%), all P pump usability can directly impact acceptance and use of features that may benefit those who wear them. Simpler pump devices that decrease perceptions of complexity may encourage broader use of this technology. © 2014 Diabetes Technology Society.

  17. Multicondition Optimization and Experimental Measurements of a Double-Blade Centrifugal Pump Impeller.

    Science.gov (United States)

    Liu, Houlin; Wang, Kai; Yuan, Shouqi; Tan, Minggao; Wang, Yong; Dong, Liang

    2013-01-01

    In order to improve internal unsteady flow in a double-blade centrifugal pump (DBCP), this study used major geometric parameters of the original design as the initial values, heads at three conditions (i.e., 80% design flow rate, 100% design flow rate, and 120% design flow rate) as the constraints conditions, and the maximum of weighted average efficiency at the three conditions as the objective function. An adaptive simulated annealing algorithm was selected to solve the energy performance calculation model and the supertransitive approximation method was applied to fix optimal weight factors of individual objectives. On the basis of hydraulic performance optimization, three-condition automatic computational fluid dynamics (CFD) optimization of impeller meridional plane for the DBCP was realized by means of Isight software integrated Pro/E, Gambit, and Fluent software. The shroud arc radii R0 and R1, shroud angle T1, hub arc radius R2, and hub angle T2 on the meridional plane were selected as the design variables and the maximum of weighted average hydraulic efficiency at the three conditions was chosen as the objective function. Performance characteristic test and particle image velocimetry (PIV) measurements of internal flow in the DBCP were conducted. Performance characteristic test results show that the weighted average efficiency of the impeller after the three-condition optimization has increased by 1.46% than that of original design. PIV measurements results show that vortex or recirculation phenomena in the impeller are distinctly improved under the three conditions.

  18. Geometric properties of hydraulic-relevant tidal bedforms

    DEFF Research Database (Denmark)

    Winter, Christian; Ferret, Yann; Lefebvre, Alice

    2013-01-01

    to technical constraints and data reduction the (historic) data bases mostly are restricted to information on mean geometrical states, whereas individual bedform properties are often not reported. Recently Lefebvre et al. (2011) showed that the hydraulic effect of asymmetric compound tidal bedforms depends...

  19. Experimental and Numerical Investigation of Coating Effect on Pump Impeller and Volute

    Directory of Open Access Journals (Sweden)

    Osman Kocaaslan

    2016-01-01

    Full Text Available In this study, an impeller and volute of a centrifugal pump were designed and numerically analyzed in order to improve the pump efficiency. Before design, experimental and theoretical studies were performed on a centrifugal water pump taken as Model Pump (MP. Design parameters were taken as 100 m3/h for volume flow rate, 18m for head and 1480 rpm for rotating speed. After the inspection of the flow field in the MP, some geometrical modifications such as impeller inlet and outlet diameters, blade inlet and exit angles, blade wrap angle, blade thickness, blade inletand exit widthswere realized to design a new pump. Numerical analyses were performed for 8 different volume flow rates overlapping with experimental operation points by Ansys-Fluent Software. In numerical studies, k-ε turbulence model and standard wall function were utilized. The experimental and computational results were compared with the model pump. According to the analysis results at design flow rate, hydraulic torque value is decreased from 56.62 Nm to 51.05 Nm, while hydraulic efficiency is increased from 55.98% to 63.09%. In addition, in order to see the roughness effect and increase the pump efficiency, the wetted surfaces of the impeller and volute were coated with a polyurethane dye material. Later, performance curves of the coated and uncoated pumps were experimentally obtained which showed that the shaft power of the pump for the coated case was decreased around 10% and the hydraulic efficiency of the pump was increased approximately 18%. According to the economic analysis by basic payback period of the polyurethane coating is less than one year and the internal income ratio for ten-year life-cycle period is around %114.

  20. HYDRAULIC AND PHYSICAL PROPERTIES OF SALTSTONE GROUTS AND VAULT CONCRETES

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, K; John Harbour, J; Mark Phifer, M

    2008-11-25

    The Saltstone Disposal Facility (SDF), located in the Z-Area of the Savannah River Site (SRS), is used for the disposal of low-level radioactive salt solution. The SDF currently contains two vaults: Vault 1 (6 cells) and Vault 4 (12 cells). Additional disposal cells are currently in the design phase. The individual cells of the saltstone facility are filled with saltstone. Saltstone is produced by mixing the low-level radioactive salt solution, with blast furnace slag, fly ash, and cement (dry premix) to form a dense, micro-porous, monolithic, low-level radioactive waste form. The saltstone is pumped into the disposal cells where it subsequently solidifies. Significant effort has been undertaken to accurately model the movement of water and contaminants through the facility. Key to this effort is an accurate understanding of the hydraulic and physical properties of the solidified saltstone. To date, limited testing has been conducted to characterize the saltstone. The primary focus of this task was to estimate the hydraulic and physical properties of three types of saltstone and two vault concretes. The saltstone formulations included saltstone premix batched with (1) Deliquification, Dissolution, and Adjustment (DDA) salt simulant (w/pm 0.60), (2) Actinide Removal Process (ARP)/Modular Caustic Side Solvent Extraction Unit (MCU) salt simulant (w/pm 0.60), and (3) Salt Waste Processing Facility (SWPF) salt simulant (w/pm 0.60). The vault concrete formulations tested included the Vault 1/4 concrete and two variations of the Vault 2 concrete (Mix 1 and Mix 2). Wet properties measured for the saltstone formulations included yield stress, plastic viscosity, wet unit weight, bleed water volume, gel time, set time, and heat of hydration. Hydraulic and physical properties measured on the cured saltstone and concrete samples included saturated hydraulic conductivity, moisture retention, compressive strength, porosity, particle density, and dry bulk density. These properties