WorldWideScience
 
 
1

Control rod drive hydraulic system  

International Nuclear Information System (INIS)

This patent describes a hydraulic system for a control rod drive (CRD). It comprises a variable output-pressure CRD pump; a charging line disposed in flow communication between the CRD pump and the CRD; a purge line disposed in flow communication between the CRD pump and the CRD, and in parallel flow with the charging line; a hydraulic control unit (HCU) disposed in flow communication in the charging line between the isolation valve and the CRD and including in series flow in the charging line an HCU check valve and a normally closed scram valve, and a scram accumulator disposed therebetween for accumulating the scram fluid at the charging pressure during the charging mode; pressurizing means disposed in flow communication with the charging line downstream of the isolation valve and upstream of the scram valve; a pressure sensor operatively connected to the charging line and responsive to the scram pressure; control means operatively connected to the CRD pump, the isolation valve, and the pressure sensor, and being effective for: opening the isolation valve while the scram valve is closed when the scram pressure drops to the minimum scram pressure; and closing the isolation valve while the scram valve is closed when the scram fluid in the charging line and in the scram accumulator reaches the charging pressure

2

Control rod drive hydraulic system  

Science.gov (United States)

A hydraulic system for a control rod drive (CRD) includes a variable output-pressure CR pump operable in a charging mode for providing pressurized fluid at a charging pressure, and in a normal mode for providing the pressurized fluid at a purge pressure, less than the charging pressure. Charging and purge lines are disposed in parallel flow between the CRD pump and the CRD. A hydraulic control unit is disposed in flow communication in the charging line and includes a scram accumulator. An isolation valve is provided in the charging line between the CRD pump and the scram accumulator. A controller is operatively connected to the CRD pump and the isolation valve and is effective for opening the isolation valve and operating the CRD pump in a charging mode for charging the scram accumulator, and closing the isolation valve and operating the CRD pump in a normal mode for providing to the CRD through the purge line the pressurized fluid at a purge pressure lower than the charging pressure.

Ose, Richard A. (San Jose, CA)

1992-01-01

3

Hydraulically powered dissimilar teleoperated system controller design  

Energy Technology Data Exchange (ETDEWEB)

This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented.

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

1996-04-01

4

Hydraulically powered dissimilar teleoperated system controller design  

International Nuclear Information System (INIS)

This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented

5

Towards Autonomous Control of Hydraulic Actuator Systems  

DEFF Research Database (Denmark)

Presentation of new developed control algorithms to increase autonomy and intelligence of hydraulic control systems. A refinement of relaytuning method is used to determine the control parameters of a lag/lead controller and a poleplacement controller. Further, a fail-safe function is developed to hinder surges and mechanical fractures. Experimental results verify the performance of the controllers.

Conrad, Finn

1998-01-01

6

Connection of hydraulic flow control system  

International Nuclear Information System (INIS)

The connection is described of a hydraulic system controling the coolant flow through the assembly of a nuclear reactor. To the hydraulically controlled control device are connected the two branches of the hydraulic system, the filling branch being connected to the primary circuit of the reactor by an open electromagnetic valve and the working branch containing the pressure source of the working liquid being connected to the drainage by a closed electromagnetic valve. A filter may be placed in the filling branch and a pressure gauge in the working branch. The two branches may be connected with a clamp with a stop valve between the control equipment and the electromagnetic valves. Also, the working branch may be linked via a safety valve with the filling branch, this between the control device and the closed electromagnetic valve and between the primary circuit and the open electromagnetic Valve. (B.S.)

7

Hydraulic Actuator System for Rotor Control  

Science.gov (United States)

In the last ten years, several different types of actuators were developed and fabricated for active control of rotors. A special hydraulic actuator system capable of generating high forces to rotating shafts via conventional bearings is addressed. The actively controlled hydraulic force actuator features an electrohydraulic servo valve which can produce amplitudes and forces at high frequencies necessary for influencing rotor vibrations. The mathematical description will be given in detail. The experimental results verify the theoretical model. Simulations already indicate the usefulness of this compact device for application to a real rotor system.

Ulbrich, Heinz; Althaus, Josef

1991-01-01

8

Hydraulic oil control system for transformer stations  

International Nuclear Information System (INIS)

'Full text:' Electrical oil control systems are commonly used to contain large volumes of spilled oil in transformer stations. Specially calibrated floats, some of which are designed to float only in oil and others only in water, are used in combination with a pump to contain oil at the catch basin below a transformer station.This electrical control system requires frequent maintenance and inspections to ensure the electrical system is not affected by any electrical surges. Also the floats need to be inspected and cleaned frequently to prevent oil or grit build up that may affect the systems' ability to contain oil.Recognizing the limitations of electrical oil control systems, Hydro One is investigating alternative control systems. A hydraulic oil control system is being investigated as an alternative which can backup oil in a containment area while allowing any water entering the containment area to pass through. Figure 1 shows a schematic of a bench-top model tested at Ryerson University. Oil and water separation occurs within the double-piped column. Oil and water are allowed to enter the external pipe column but only water is allowed to exit the internal pipe column. The internal pipe column is designed to generate enough hydrostatic pressure to ensure the oil is contained in the external pipe column.The hydraulic oil control system provides a reliable control mechanism and requires less maintenance compared to that of the electrical control system. Since the hydraulic oil control system has no moving parts, nor would any parts that require electricity, it is not affected by electrical surges such as lightening.The maintenance requirements of the hydraulic oil control system are: the removal of any oil and grit from the catch basin, and the occasional visual inspection for any crack or clogs in the system. (author)

9

Control issues for a hydraulically powered dissimilar teleoperated system  

International Nuclear Information System (INIS)

This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented. (Schilling's Titan II hydraulic manipulators are the slave manipulators and the master manipulators are from the Oak Ridge National Laboratory-developed Advanced Servo Manipulator.)

10

A Flexible Adjustment and Control System for Hydraulic Machines  

Directory of Open Access Journals (Sweden)

Full Text Available Due to the advantages of hydraulic systems with variable displacement, it was necessary to design a control system that can adjust the pressure, flow, power or a combination of these features, that can be easily integrated into the pump body without changing its mechanical construction. The objective of this work was to study the dynamic behavior of this electro-hydraulic control system. To achieve these objectives, first the adjusting system was analyzed by numerical simulations, and then a stand was constructed for testing the performance of these adjustable pumps. It was shown that this control system is superior to existing systems.

Daniel Banyai

2012-01-01

11

Toward optimal multi-actuator displacement controlled mobile hydraulic systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The research in this thesis is primarily motivated by rising fuel costs and increasingly stringent emissions regulations for diesel engines. These factors increase the cost of operation and the cost of production of mobile hydraulic machine systems, thereby providing large incentives for the discoveries of more efficient hydraulic system solutions. Additionally, sensors and electronics are becoming more openly accepted for use in mobile hydraulic machine systems and they are key enablers to...

Zimmerman, Joshua David

2012-01-01

12

Hydraulic-Ball (HY-Ball) Control System  

International Nuclear Information System (INIS)

The Hy-Ball control system consists of a large number of small tubes vertically penetrating the active core region; the tubes contain movable poison elements (either spherical or cylindrical), which are hydraulically lifted upward from within the active core region to increase core reactivity. Reactor water is the actuating fluid. Hy-Ball columns occupy fuel-element lattice positions in a homogeneous fuel-element configuration. This configuration, with finely subdivided control elements, practically eliminates local water-hole power peaking and provides good control of the radial power distribution. By limitation of the amount of reactivity controlled by a single Hy-Ball column assembly to 0.1% or less, it is unnecessary to operate the poison elements in any position other than either the fully-inserted or fully-withdrawn positions. Elimination of intermediate positions results in simplicity of the system and avoids the inherent axial power perturbation resulting from partially inserted control elements. Physics studies indicate that up to about 40% more power can be obtained from a Hy-Ball-controlled core than from a core with conventional control rods. Tests simulating all reactor operating conditions except radiation are being performed for evaluation of costs, operational characteristics and long-term reliability effects. (author)

13

Hydraulic engine valve actuation system including independent feedback control  

Science.gov (United States)

A hydraulic valve actuation assembly may include a housing, a piston, a supply control valve, a closing control valve, and an opening control valve. The housing may define a first fluid chamber, a second fluid chamber, and a third fluid chamber. The piston may be axially secured to an engine valve and located within the first, second and third fluid chambers. The supply control valve may control a hydraulic fluid supply to the piston. The closing control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the second fluid chamber to the supply control valve. The opening control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the supply control valve to the second fluid chamber.

Marriott, Craig D

2013-06-04

14

System and method for controlling hydraulic pressure in electro-hydraulic valve actuation systems  

Energy Technology Data Exchange (ETDEWEB)

A control system for an engine includes a first lift control module and a second lift control module. The first lift control module increases lift of M valves of the engine to a predetermined valve lift during a period before disabling or re-enabling N valves of the engine. The second lift control module decreases the lift of the M valves to a desired valve lift during a period after enabling or re-enabling the N valves of the engine, wherein N and M are integers greater than or equal to one.

Brennan, Daniel G; Marriott, Craig D; Cowgill, Joel; Wiles, Matthew A; Patton, Kenneth James

2014-09-23

15

Tap Water Hydraulic Control Systems - Design and Industrial Applications. Chapter 7 in Advances in Hydraulic Control Systems.  

DEFF Research Database (Denmark)

Deals with development and design of modern tap water hydraulic components and systems, in particalar the Danfoss Nessie-family of components and systems working with pure tap water without any kind of additives. Typical industrial applications are presented and the perspectives of new industrial applications and the environmental benefits are in focus, in particular in the food processing industry and in fire-fighting systems.

Conrad, Finn

1996-01-01

16

Evaluation of Linear and Non-Linear Control Schemes Applied to a Hydraulic Servo System  

DEFF Research Database (Denmark)

Due to the innovation of low-cost electronics such as sensors, microcontrollers etc., the focus on highperformance motion control is increasing. This work focuses on position control of single-input single-output hydraulic servo-systems in general. A hydraulically actuated robotic manipulator is used as test facility acting as load for the hydraulic servo system. An experimentally verified non-linear model of the complete system has been developed and used to design a series of both linear and non-linear control schemes. The controllers from each category are compared with respect to design parameters such as performance, robustness and implementation

Andersen, Torben Ole; Hansen, Michael Rygaard

2005-01-01

17

Specific features pertinent to modeling of hydraulic systems containing control members  

Science.gov (United States)

The theoretical principles applied for modeling of hydraulic systems fitted with control members that allow a hydraulic line's specific features (topology) to be taken into account are considered. Such modeling opens the possibility to predict the actual flow (throttling) characteristics at early design stages and timely introduce the appropriate corrections in pipeline topology. The modeling problem is solved with the use of generalized thermodynamic analysis methods. The mathematical models of hydraulic systems containing control members are brought to the level of real-time simulation models, which can be used for setting up computation experiments for achieving better performance of automatic closed-loop control systems.

Tverskoy, Yu. S.; Marshalov, E. D.

2014-09-01

18

Fireproof Brake Hydraulic System.  

Science.gov (United States)

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

S. M. Warren, J. R. Kilner

1981-01-01

19

Optimization for PID Control Parameters on Hydraulic Servo Control System Based on Artificial Bee Colony Optimization Algorithm  

Directory of Open Access Journals (Sweden)

Full Text Available PID control is used widely in hydraulic servo control system. The PID control parameters are very important to performance of hydraulic servo control system and how to find rapidly the optimum values of PID control parameters is very difficult problem. Based on Matlab/simulink software and taking the IATE standards of the optimization design as objective function, a global search optimization method, called Artificial Bee Colony Optimization Algorithm was applied for the optimization of the three parameters of PID controller of electric-hydraulic servo system of 6-DOF parallel platform. Simulation results show that the proposed parameter optimum method is an effective tuning strategy and has good performance.

Youxin Luo

2012-03-01

20

Research of the Electro-hydraulic Servo System Based on RBF Fuzzy Neural Network Controller  

Directory of Open Access Journals (Sweden)

Full Text Available This article describes the composition and working principle of electro-hydraulic position servo control system, and establishes a systematic mathematical model. This article presents a controller which is based on Fuzzy neural networks for an electro-hydraulic speed governor. The design process of the RBF Fuzzy neural network control is introduced in detail. This controller which combines the advantages of the Fuzzy control and Neutral networks control can get the best PID parameters by self-adjustment on line. The simulation study proves that this control system has a better adaptability and can improve the control effect greatly.

Huaizhong Chen

2012-09-01

 
 
 
 
21

Co-Simulation Research of the Mechanical-Hydraulic-Control Coupling System of ITER Tractor  

International Nuclear Information System (INIS)

The virtual prototyping models of the mechanical, hydraulic and control system of the ITER tractor were built with CATIA, ADAMS and MATLAB/Simulink respectively according to its heavy load and high precision characteristics, and the data transfer between the different models was accomplished by the integration interface between different software. Consequently the virtual experimental platform for the multi-disciplinary co-simulation was established. A co-simulation study of the mechanical-hydraulic-control coupling system of the ITER tractor was carried out. The synchronization servo control of parallel hydraulic cylinders was implemented, and the tracking control of the preconcerted trajectory of the hydraulic cylinders was realized on the established experimental platform. This paper presents the optimization design and technology rebuilding for the complicated coupling system with its theoretic foundation and co-simulation virtual experimental platform.

22

Co-Simulation Research of the Mechanical-Hydraulic-Control Coupling System of ITER Tractor  

Science.gov (United States)

The virtual prototyping models of the mechanical, hydraulic and control system of the ITER tractor were built with CATIA, ADAMS and MATLAB/Simulink respectively according to its heavy load and high precision characteristics, and the data transfer between the different models was accomplished by the integration interface between different software. Consequently the virtual experimental platform for the multi-disciplinary co-simulation was established. A co-simulation study of the mechanical-hydraulic-control coupling system of the ITER tractor was carried out. The synchronization servo control of parallel hydraulic cylinders was implemented, and the tracking control of the preconcerted trajectory of the hydraulic cylinders was realized on the established experimental platform. This paper presents the optimization design and technology rebuilding for the complicated coupling system with its theoretic foundation and co-simulation virtual experimental platform.

Yang, Xiuqing; Luo, Minzhou; Mei, Tao; Yao, Damao

2009-06-01

23

Direct Drive Electro-hydraulic Servo Control System Design with Self-Tuning Fuzzy PID Controller  

Directory of Open Access Journals (Sweden)

Full Text Available According to the nonlinear and time-varying uncertainty characteristics of direct drive electro-hydraulic servo control system, a self-tuning fuzzy PID control method with speed change integral and differential ahead optimizing operator is put forward by combining fuzzy inference and traditional PID control in this paper.The rule of fuzzy logic is designed, the membership function of the fuzzy subsets is determined and lookup table method is used to correcte the PID parameters in real-time. Finally the simulation is conducted with the typical input signal, such as tracking step, sine etc. The simulation results show that?the self-tuning fuzzy PID control system can effectively improve the dynamic characteristic when the system is out of the range of the operating point compared with the traditional PID control system, there is obvious improvement in the indexes of rapidity, stability and accuracy,  and fuzzy self-tuning PID Control is more robust, and more suitable for direct drive electro-hydraulic servo system.

Wang Yeqin

2013-06-01

24

Pressure control in hydraulic systems with variable or constant pumps?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The paper deals with electrohydraulic supply systems with variable (adjustable( supply pressures. Two control concepts are used in practice: the pressure control concept using a variable pump and constant speed of the driving electric motor as the commonly used concept, and the pressure control concept with a constant pump and a speed-controlled electric motor as the alternative concept. The typical features and the applicability of both conceps, as well as their dynamic responses are studied...

Lovrec, Darko; Ulaga, Samo

2012-01-01

25

Application of simple adaptive control to water hydraulic servo cylinder system  

Science.gov (United States)

Although conventional model reference adaptive control (MRAC) achieves good tracking performance for cylinder control, the controller structure is much more complicated and has less robustness to disturbance in real applications. This paper discusses the use of simple adaptive control (SAC) for positioning a water hydraulic servo cylinder system. Compared with MRAC, SAC has a simpler and lower order structure, i.e., higher feasibility. The control performance of SAC is examined and evaluated on a water hydraulic servo cylinder system. With the recent increased concerns over global environmental problems, the water hydraulic technique using pure tap water as a pressure medium has become a new drive source comparable to electric, oil hydraulic, and pneumatic drive systems. This technique is also preferred because of its high power density, high safety against fire hazards in production plants, and easy availability. However, the main problems for precise control in a water hydraulic system are steady state errors and overshoot due to its large friction torque and considerable leakage flow. MRAC has been already applied to compensate for these effects, and better control performances have been obtained. However, there have been no reports on the application of SAC for water hydraulics. To make clear the merits of SAC, the tracking control performance and robustness are discussed based on experimental results. SAC is confirmed to give better tracking performance compared with PI control, and a control precision comparable to MRAC (within 10 ?m of the reference position) and higher robustness to parameter change, despite the simple controller. The research results ensure a wider application of simple adaptive control in real mechanical systems.

Ito, Kazuhisa; Yamada, Tsuyoshi; Ikeo, Shigeru; Takahashi, Koji

2012-09-01

26

Control method and system for hydraulic machines employing a dynamic joint motion model  

Science.gov (United States)

A control method and system for controlling a hydraulically actuated mechanical arm to perform a task, the mechanical arm optionally being a hydraulically actuated excavator arm. The method can include determining a dynamic model of the motion of the hydraulic arm for each hydraulic arm link by relating the input signal vector for each respective link to the output signal vector for the same link. Also the method can include determining an error signal for each link as the weighted sum of the differences between a measured position and a reference position and between the time derivatives of the measured position and the time derivatives of the reference position for each respective link. The weights used in the determination of the error signal can be determined from the constant coefficients of the dynamic model. The error signal can be applied in a closed negative feedback control loop to diminish or eliminate the error signal for each respective link.

Danko, George (Reno, NV)

2011-11-22

27

Design and Optimization of Controllers for an Electro-Hydraulic System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Electro-Hydraulic (EH) systems are commonly used in the industry for applications that require high power-weight ratios and large driving forces. The EH system studied in this master thesis have recently been upgraded with new hardware components and as a part of this upgrade a new controller was requested. The system consists of a controller that computes a control signal for an electric motor. The motor drives a gear pump that generates a flow of hydraulic fluid. The flow is then directed t...

Andre?, Simon

2014-01-01

28

Parallel Control of Velocity Control and Energy-Saving Control for a Hydraulic Valve-Controlled Cylinder System Using Self-Organizing Fuzzy Sliding Mode Control  

Science.gov (United States)

Conventional hydraulic valve-controlled systems that incorporate positive displacement pumps and relief valves have a problem of low energy efficiency. The objective of the research is to implement parallel control of energy-saving control in an electro-hydraulic load-sensing system and velocity control in a hydraulic valve-controlled cylinder system to achieve both high velocity control accuracy and low input power simultaneously. The overall control system is a two-input two-output system. For that, the control strategy of self-organizing fuzzy sliding mode control (SOFSMC) is developed in this study to reduce the fuzzy rule number and to self-organize on-line the fuzzy rules. To compare the energy-saving performance, the velocity control is implemented under three different energy-saving control systems, such as load-sensing control system, constant supply pressure control system and conventional hydraulic system. The parallel control of the velocity control and energy-saving control by the SOFSMC is implemented experimentally.

Chiang, Mao-Hsiung; Chien, Yu-Wei

29

Modeling and Controller Design of an Electro-Hydraulic Actuator System  

Directory of Open Access Journals (Sweden)

Full Text Available Problem statement: Electro-hydraulic actuators are widely used in motion control application. Its valve needs to be controlled to determine direction of the motion. Mathematical modeling is a description of a system in terms of equations. It can be divided into two parts; physical modeling and system identification. The objective of this study was to obtain mathematical model of an electro-hydraulic system using system identification technique by estimating model using System Identification Toolbox in MATLAB. Approach: Experimental works were done to collect input and output data for model estimation and ARX model was chosen as model structure of the system. The best model was accepted based on the best fit criterion and residuals analysis of autocorrelation and cross correlation of the system input and output. PID controller was designed for the model through simulation in SIMULINK. The controller is tuning by Ziegler-Nichols method. The simulation work was verified by applying the controller to the real system to achieve the best performance of the system. Results: The result showed that the output of the system with controller in simulation mode and experimental works were improved and almost similar. Conclusion/Recommendations: The designed PID controller can be applied to the electro-hydraulic system either in simulation or real-time mode. The self-tuning or automatic tuning controller could be developed in future work to increase the reliability of the PID controller.

M. F. Rahmat

2010-01-01

30

Double Adaptive Fuzzy Sliding Mode Control Scheme for Electro-hydraulic Velocity Servo System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pointing on uncertainties in the velocity servo system, caused by servo system cant model accurately, may cause the deterioration of the control quality of the Electro-Hydraulic Velocity Servo System (EHVSS) and even lead to its instability. An Double Adaptive Fuzzy Sliding Mode Control (DAFSMC) algorithm is proposed for an EHVSS. The proposed control strategy has fast response and good disturbance rejection capability. The numerical simulation is presented to verify the effectiveness of the ...

Shao Jiang Wang; Qi Zhang; Rui Tang

2012-01-01

31

Adaptive Backstepping Control of Nonlinear Hydraulic-Mechanical System Including Valve Dynamics  

Directory of Open Access Journals (Sweden)

Full Text Available The main contribution of the paper is the development of an adaptive backstepping controller for a nonlinear hydraulic-mechanical system considering valve dynamics. The paper also compares the performance of two variants of an adaptive backstepping tracking controller with a simple PI controller. The results show that the backstepping controller considering valve dynamics achieves significantly better tracking performance than the PI controller, while handling uncertain parameters related to internal leakage, friction, the orifice equation and oil characteristics.

M. Choux

2010-01-01

32

Using Feedback Error Learning for Control of Electro Hydraulic Servo System by Laguerre  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, a new Laguerre controller is proposed to control the electro hydraulic servo system. The proposed controller uses feedback error learning method and leads to significantly improve performance in terms of settling time and amplitude of control signal rather than other controllers. All derived results are validated by simulation of nonlinear mathematical model of the system. The simulation results show the advantages of the proposed method for improved control in terms of both settling time and amplitude of control signal.

Amir Reza Zare Bidaki

2014-01-01

33

Design and development of low speed dynamometer using electro hydraulic servo control system  

International Nuclear Information System (INIS)

High torque low speed oil hydraulic motors are required to be used in fuelling machine of 500 MWe PHWRs. High torque low speed motors presently available in market are designed for heavy earth moving equipment where high torque at moderately low speed is desired. To test these types of motors, low speed dynamometers are required. An attempt has been made to develop an indigenous low speed dynamometer by electro hydraulic servo control system which can overcome the drawbacks of powder type dynamometer design. (author). 5 refs., 4 figs

34

Space Shuttle Main Engine control system. [hydraulic actuator with digital control  

Science.gov (United States)

The Space Shuttle Main Engine is a reusable, high-performance rocket engine being developed by the Rocketdyne Div. of Rockwell International to satisfy the operational requirements of the Space Shuttle Orbiter Vehicle. The design incorporates a hydraulically actuated, closed-loop servosystem controlled and monitored by a programmable electronic digital controller. The controller accepts vehicle commands for the various engine operational phases, positions the appropriate valves, monitors the engine for the required performance precisions and conditions, and provides redundancy management.

Seitz, P. F.; Searle, R. F.

1973-01-01

35

Fault Detection and Isolation for Hydraulic Control  

Science.gov (United States)

Pressure sensors and isolation valves act to shut down defective servochannel. Redundant hydraulic system indirectly senses failure in any of its electrical control channels and mechanically isolates hydraulic channel controlled by faulty electrical channel so flat it cannot participate in operating system. With failure-detection and isolation technique, system can sustains two failed channels and still functions at full performance levels. Scheme useful on aircraft or other systems with hydraulic servovalves where failure cannot be tolerated.

1987-01-01

36

Status quo of applications of new control theories for hydraulic control systems; Shinseigyo riron no yuatsu eno oyo no genjo  

Energy Technology Data Exchange (ETDEWEB)

This paper describes application of a new control theory to hydraulics. The modern control theory has become applied to hydraulics since about the 1940's, and optimal polarity arrangement by using the status feedback and adaptive control represented by MRAC have emerged. Thereafter, the robust control comes on stage as a fusion of the status space method and the frequency zone theory. For the application thereof, much discussions were given on adaptive control represented by MRAC in order to cover large variation in system parameters in hydraulic control. Since variable parameters are included, there are problems of identification of safety limit, and time delay. Fuzzy control allowing the mathematical model of the subject system to be unclear and neural net control are expanding their applications because of their easiness of handling. The robust control has also begun being applied partly, which is regarded useful for servos. Design freedom is high because target followability and stability are designed separately. However, reliable introduction of two-freedom degree control system such as H{sub {infinity}} control is indispensable. The paper also describes the single adaptive control (SAC) and the sliding mode control (SMC). (NEDO)

Yokota, S. [Tokyo Institute of Technology, Tokyo (Japan)

2000-05-15

37

Analysis and compensation of an aircraft simulator control loading system with compliant linkage. [using hydraulic equipment  

Science.gov (United States)

A hydraulic control loading system for aircraft simulation was analyzed to find the causes of undesirable low frequency oscillations and loading effects in the output. The hypothesis of mechanical compliance in the control linkage was substantiated by comparing the behavior of a mathematical model of the system with previously obtained experimental data. A compensation scheme based on the minimum integral of the squared difference between desired and actual output was shown to be effective in reducing the undesirable output effects. The structure of the proposed compensation was computed by use of a dynamic programing algorithm and a linear state space model of the fixed elements in the system.

Johnson, P. R.; Bardusch, R. E.

1974-01-01

38

Hydraulic system provides smooth control of large tracking and antenna drive systems at very low tracking rates  

Science.gov (United States)

Hydraulic system provides smooth control of large tracking and antenna drive systems at very low tracking rates. This configuration modifies a series connection of the drive motors with compensating orifices to offset the effects of drain line loss. Linearization of response by eliminating cogging or cyclic operation is thus obtained.

Parker, G. L.

1967-01-01

39

Control system developments for a range of kinematically redundant hydraulic manipulators  

International Nuclear Information System (INIS)

This paper describes a range of control system improvements developed and implemented for in-reactor use during the last three years. Novel control techniques have been developed to provide accurate closed-loop velocity control of pumped hydraulic manipulator joints under a wide range of operating conditions. As a result the supervisory computer system can provide accurate trajectory following, even when more than ten joints are required to move simultaneously. Accurately coordinated motion has given rise to some spectacular gains in in-reactor performance in terms of deployment time, safety and accessibility. The same low-level control improvements have made it feasible to integrate and use the 'geometric controller' to provide accurate resolved motion control of a kinematically redundant manipulator. Examples of recent in-reactor use of all these techniques are given. (author)

40

Electrokinetic high pressure hydraulic system  

Science.gov (United States)

An electrokinetic high pressure hydraulic pump for manipulating fluids in capillary-based systems. The pump uses electro-osmotic flow to provide a high pressure hydraulic system, having no moving mechanical parts, for pumping and/or compressing fluids, for providing valve means and means for opening and closing valves, for controlling fluid flow rate, and manipulating fluid flow generally and in capillary-based systems (Microsystems), in particular. The compact nature of the inventive high pressure hydraulic pump provides the ability to construct a micro-scale or capillary-based HPLC system that fulfills the desire for small sample quantity, low solvent consumption, improved efficiency, the ability to run samples in parallel, and field portability. Control of pressure and solvent flow rate is achieved by controlling the voltage applied to an electrokinetic pump.

Paul, Phillip H. (Livermore, CA); Rakestraw, David J. (Fremont, CA); Arnold, Don W. (Livermore, CA); Hencken, Kenneth R. (Pleasanton, CA); Schoeniger, Joseph S. (Oakland, CA); Neyer, David W. (Castro Valley, CA)

2001-01-01

 
 
 
 
41

Water Hydraulic Systems  

DEFF Research Database (Denmark)

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 measurements from a similar robot manipulator driven by tap water hydraulic components. Experimental and simulation results are compared for evaluation and verification of developed mathematical models of the motion control of the manipulator. Furthermore, this paper presents the selected experimental results and performance results.

Conrad, Finn

2005-01-01

42

Control of a hydraulic system by means of a fuzzy approach  

Directory of Open Access Journals (Sweden)

Full Text Available Non linear models can be represented conveniently by Takagi-Sugeno fuzzy models when nonlinearities are bounded. This approach uses a collection of linear models which are interpolated by non linear functions. Then the global control law is the interpolation by the same functions of each feedback associated to each linear model. A Lyapunov approach enables to compute these feedback gains. The number of linear models depends directly on the number of nonlinearities the system has. The more models there are, the more difficult it is to guarantee the stability of the closed loop. This paper proposes a method to reduce the number of linear models by assuming a number of nonlinearities considered as uncertainties and to guarantee the global exponential stability of the system. This method is applied on a hydraulic system.

Mohamed Ksantini

2013-07-01

43

On Application of Second Order Sliding Mode Control to Electro-Hydraulic Systems  

DEFF Research Database (Denmark)

This paper discusses the application of second order mode controls to hydraulic valve-cylinder drives with a special focus on the limitations resulting from nonlinear dynamic effects in flow control valves. Second order sliding mode algorithms appear highly attractive in the successive implementation of sliding mode control, achieving continuous control inputs, while maintaining the main properties of sliding modes. Under certain model assumptions, some of these controllers may even be applied as output feedback controllers. However, intrinsic nonlinear dynamic effects of hydraulic valves such as slew rates and time delays arising in the amplification stages, limits the applicability of such methods, and may lead to partial losses of robustness and limit cycles. These properties are analyzed and experimentally verified, and compensation methods are proposed. The application of the second order sliding algorithm known as the super twisting controller is considered for output feedback control and compared withconventional first order sliding mode control. The controllers under consideration are applied for position tracking control of a hydraulic valve-cylinder drive exhibiting strong variations in inertia- and gravitational loads. Results demonstrate that the super twisting algorithm may be successfully applied for output feedback control of hydraulic valve-cylinder drives, with modifications guaranteeing robust control performance in a small vicinity of the control target.

Schmidt, Lasse; Andersen, Torben Ole

2014-01-01

44

Development of adaptive control system using the fuzzy theory for thermal-hydraulic analysis code, AQUA  

International Nuclear Information System (INIS)

An adaptive control system using the Fuzzy theory has been implemented into the single-phase three-dimensional thermal-hydraulic analysis code AQUA. The system is designed to yield the optimum time step sizes as a control parameter. It fully utilizes the experiences accumulated by numerical experts: e.g., the use of a very small time step size when a symptom of instabilities appear. Asymtotic behaviors in the course of numerical integration due to AQUA are monitored by checking mass residual and relative variations for three velocity components u, v and w, turbulent parameters k and ? and enthalpy h every time step. The validity of overall idea could be interpreted by analogy with the fact experts in many industries are capable of operating plants without profound knowledge of the control characteristics. As a result of numerical experiments, the total CPU time has been reduced typically by 40% in comparison with the cases when the time step size is not controlled by the system. In general, the adaptive control system using the Fuzzy theory is an efficient measure to save computing efforts when one wishes to perform an extremely large scale simulation over a long transient time span. (author)

45

Development, field testing and implementation of automated hydraulically controlled, variable volume loading systems for reciprocating compressors  

Energy Technology Data Exchange (ETDEWEB)

Automated, variable volume unloaders provide the ability to smoothly load/unload reciprocating compressors to maintain ideal operations in ever-changing environments. Potential advantages provided by this load control system include: maximizing unit capacity, optimizing power economy, maintaining low exhaust emissions, and maintaining process suction and discharge pressures. Obstacles foreseen include: reliability, stability, serviceability and automation integration. Results desired include: increased productivity for the compressor and its operators, increased up time, and more stable process control. This presentation covers: system design features with descriptions of how different types of the devices were developed, initial test data, and how they can be effectively operated; three actual-case studies detailing the reasons why automated, hydraulically controlled, variable volume, head-end unloaders were chosen over other types of unloading devices; sophisticated software used in determining the device sizing and predicted performance; mechanical and field considerations; installation, serviceability and operating considerations; device control issues, including PC and PLC considerations; monitoring of actual performance and comparison of such with predicted performance; analysis of mechanical reliability and stability; and preliminary costs versus return on investment analysis. (author)

Hickman, Dwayne A. [ACI Services, Inc., Cambridge, OH (United States); Slupsky, John [Kvaerner Process Systems, Calgary, Alberta (Canada); Chrisman, Bruce M.; Hurley, Tom J. [Cooper Energy Services, Oklahoma City, OK (United States). Ajax Division

2003-07-01

46

Free Valve Technology : – Development of a control system for an electronically controlled pneumatic-hydraulic valve actuation system for an automotive engine  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This master thesis is a project commissioned by AVL Södertälje Powertrain Engineering AB. The purpose has been to develop a control system for an electronic pneumatic-hydraulic valve actuation system installed in a one cylinder test engine. AVL is an independent company which develops powertrain systems with internal combustion engines as well as instrumentation and test systems. The valve actuation system is to be used in their research and development of internal combustion technology. Th...

Gundersen, Řyvind

2009-01-01

47

Study of modern state of quality control hydraulic liquids  

Directory of Open Access Journals (Sweden)

Full Text Available  In the work present of investigation results of the state control quality system of hydraulic liquids in the contemporary modem conditions of the consumption and storage. To present the results of investigation of change hydraulic liquids quality in the exploitation aviations technical. Propose the directions the perfection of the control quality liquids for hydraulic system aircraft.

?.?. ????????

2006-01-01

48

Thermo hydraulic analysis and control of the HELOKA water cooling system  

International Nuclear Information System (INIS)

In the framework of the European Fusion Program, various Helium cooled Test Blanket Modules (TBM), such as the Helium Cooled Pebble Bed (HCPB) blanket, are proposed for tests under reactor relevant experimental conditions in ITER. To qualify the TBM module design for ITER, it is necessary to test full size mock-ups in a helium loop under realistic pressure, temperature and flow conditions. The HCPB mock-ups will be tested at the Helium Loop Karlsruhe (HELOKA) test facility, at present in advanced status of design. As far as possible, HELOKA shall operate with requirements similar to those of the Helium coolant circuit of the TBM modules in ITER. One of the main requirements of the ITER main helium loop is its ancillary water cooling system, hence the need of a Water Cooling System (WCS) for HELOKA. An existing WCS, recently used for the COMET (Core Melt Accidents) experiment, is foreseen for this purpose. The system, designed in the 80's for a heat load of about 7 MW, will be used first for the HELOKA TBM experimental campaign, where the maximum expected heat load does not exceed 5 MW, and later on, for the Test Divertor Modules (TDM). The thermal hydraulic effect has been studied using the system code RELAP5, where the pumps, the heat exchanger (HX), the cooling tower, the valves, the piping, etc., can be modeled and the whole loop can be simulated for steady state, transient accident processes or cyclic operation. In order to improve the efficiency of the system and save energy, it has been proposed to install variable frequency converters for the electric drivers and new feedback controllers. An evaluation of the overall performances of the system with the proposed feedback controllers has been conducted with computer models developed with SIMULINK. At present most of the components have been modeled using manufacturer's data. For some components, technical data are scarce and therefore a comparison with experimental data to validate the models is planned. After the validation based on the experimental data, the code will allow the testing of the control strategies for steady state, transients or cyclic operation and check the possible upgrade of the system to 10 MW (expected heat load for the HELOKA TDM experimental campaign). The control system is being modernized using state of the art hardware and software components. The upgrade also includes additional sensors and a new data acquisition system. (author)

49

Trends in Modelling, Simulation and Design of Water Hydraulic Systems – Motion Control and Open-Ended Solutions  

DEFF Research Database (Denmark)

The paper presents and discusses a R&D-view on trends in development and best practise in modelling, simulation and design of both low-pressure and high-pressure tap water hydraulic components and systems for motion control as well as open-ended solutions various industrial applications. The focus is on the advantages using ordinary tap water and the range of application areas are illustrated with examples, in particular within the food processing industry, humidification operations, water mist systems for fire fighting, high water pressure cleaners, water moisturising systems for wood processing, lumber drying process and mobile machines and equipment that operate in environmentally sensitive surroundings. Today’s progress in water hydraulics includes electro-water hydraulic proportional valves and servovalves for design of motion control solutions for machines and robots. The remarkable property is that the components operate with pure water from the tap without additives of any kind. Hence water hydraulicstakes the benefit of pure water as fluid being environmentally friendly, easy to clean sanitary design, non-toxic, non-flammable, inexpensive, readily available and easily disposable. The low-pressure tap water hydraulic systems cover up to around 50 bar, and 2-4 kW having a strong potential to compete with pneumatic and electrical solutions in many applications. The high-pressure water hydraulic systems cover typically up to 160 bar pressure from pump and to motors and actuators 140 bar. Recently, dedicated pumps and accessories running with sea-water as fluid are available. A unique solution is to use reverse osmosis to generate drinking water from sea-water, and furthermore for several off-shore applications. Furthermore, tap water hydraulic components of the Nessie® family and examples of measured performance characteristics are presented and the trends in industrial applications and need for future are discussed.

Conrad, Finn Technical University of Denmark,

2006-01-01

50

Switching sliding mode force tracking control of piezoelectric-hydraulic pump-based friction element actuation systems for automotive transmissions  

Science.gov (United States)

In this study, a nonlinear sliding-mode controller is designed for force tracking of a piezoelectric-hydraulic pump (PHP)-based actuation system, which is developed to replace the current electro-hydraulic actuation systems for automatic transmission (AT) friction elements, such as band brakes or clutches. By utilizing the PHP, one can eliminate the various hydraulic components (oil pump, regulating valve and control valve) in current ATs and achieve a simpler configuration with more efficient operation. With the derived governing equation of motion of the PHP-based actuation system integrated with the friction element (band brake), a switching control law is synthesized based on the sliding-mode theory. To evaluate the effectiveness of the proposed control law, its force tracking performance for the engagement of a friction element during an AT 1\\to 2 up-shift is examined experimentally. It is shown that one can successfully track the desired force trajectory for AT shift control with small tracking error. This study demonstrates the potential of the PHP as a new controllable actuation system for AT friction elements.

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

2009-08-01

51

Switching sliding mode force tracking control of piezoelectric-hydraulic pump-based friction element actuation systems for automotive transmissions  

International Nuclear Information System (INIS)

In this study, a nonlinear sliding-mode controller is designed for force tracking of a piezoelectric-hydraulic pump (PHP)-based actuation system, which is developed to replace the current electro-hydraulic actuation systems for automatic transmission (AT) friction elements, such as band brakes or clutches. By utilizing the PHP, one can eliminate the various hydraulic components (oil pump, regulating valve and control valve) in current ATs and achieve a simpler configuration with more efficient operation. With the derived governing equation of motion of the PHP-based actuation system integrated with the friction element (band brake), a switching control law is synthesized based on the sliding-mode theory. To evaluate the effectiveness of the proposed control law, its force tracking performance for the engagement of a friction element during an AT 1?2 up-shift is examined experimentally. It is shown that one can successfully track the desired force trajectory for AT shift control with small tracking error. This study demonstrates the potential of the PHP as a new controllable actuation system for AT friction elements

52

Space shuttle main engine: Hydraulic system  

Science.gov (United States)

The hydraulic actuation system of the space shuttle main engine is discussed. The system consists of five electrohydraulic actuators and a single engine filter used to control the five different propellant valves, which in turn control thrust and mixture ratio of the space shuttle main engine. The hydraulic actuation system provides this control with a precision of 98.7 percent or an error in position no greater than 1.3 percent of full scale rotational travel for critical positions.

Geller, G.; Lamb, C. D.

1981-01-01

53

Hydraulic Motor Driving Variable-Pitch System for Wind Turbine  

Directory of Open Access Journals (Sweden)

Full Text Available The present hydraulic variable-pitch mechanism of wind turbine uses three hydraulic cylinders to drive three crank and connecting rod mechanisms respectively; the blades are moved with the cranks. The hydraulic variable-pitch mechanism has complex structure, occupies a lot of space and its maintenance is trouble. In order to make up for the shortcomings of hydraulic cylinder variable-pitch system, the present hydraulic variable-pitch mechanism should be changed as follows: hydraulic motors are used to drive gears; gears drive blades; the electro-hydraulic proportional valves are used to control hydraulic motors. The hydraulic control part and electrical control part of variable-pitch system is redesigned. The new variable-pitch system is called hydraulic motor driving variable-pitch system. The new variable-pitch system meets the control requirements of blade pitch, makes the structure simple and its application effect is perfect.    

Ye HUANG

2013-11-01

54

Improvement of Hydraulic Edge Position Control System by Proportion Sliding Mode of Self-tuning Switching Gain  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Aiming at the problem of tracking performance degradation of hydraulic EPC system caused by time-varying inertia parameters, nonlinear and external disturbances, the proportion sliding mode control of fuzzy self-tuning gain was proposed. The EPC system state space model on deviation parameters was established and the main feedback sliding mode switching algorithm was designed. The fuzzy method was used to dynamically adjust the proportion sliding mode switching gain by product of the switchin...

Jin Baoquan; Chen Dongbing

2012-01-01

55

Integrating Experiment, Modeling and Design using a Hands on Hydraulic Positioning Laboratory for Mechanical Control Systems Education  

Science.gov (United States)

As part of a laboratory intensive curriculum, Mechanical Engineering students at California Polytechnic State University, San Luis Obispo are required to take a senior level class in Mechanical Control Systems. In addition to three one-hour lectures, students attend a weekly three hour laboratory session where course concepts are reinforced through hands-on modeling and experimentation. This paper describes a newly implemented and innovative laboratory experience which is centered on a hydraulic position control system. Often experiments in Mechanical Controls are heavily influenced by non-linearities such as friction or backlash which cause inexperienced students to lose confidence in linear system modeling as an effective analysis and design tool. A hydraulic system was chosen for this laboratory due to excellent correlation between experimental results and the linear modeling techniques taught in the course. This laboratory experience is designed to integrate linear system modeling techniques, experimentation and data collection, control system design, and design verification through physical testing using a variety of hardware and software tools. The main objectives of the laboratory are to give the students practice and confidence in advanced control system modeling, experience with precision hydraulic positioning systems, practice in designing Proportional-Integral (PI) controllers, exposure to digital control systems and experience and physical understanding of the sometimes dramatic condition of instability. The methodology includes a unique procedure that uses root locus concepts and asks the students to drive the system to instability to determine system parameters. The paper describes the laboratory experience in detail and gives some example results and an assessment of student learning.

Birdsong, Charles; Owen, Frank; Ridgely, John; Widmann, James

2009-08-11

56

46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.  

Science.gov (United States)

...128.240 Hydraulic or pneumatic power and control—materials...valves) for hydraulic or pneumatic power and control systems...non-standard hydraulic or pneumatic component (such as control...valves, relief valves, and regulators) may be accepted by...

2010-10-01

57

Combined hydraulic and regenerative braking system  

Science.gov (United States)

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

Venkataperumal, Rama R. (Troy, MI); Mericle, Gerald E. (Mount Clemens, MI)

1981-06-02

58

Hydraulic management of a soil moisture controlled SDI wastewater dispersal system in an Alabama Black Belt soil.  

Science.gov (United States)

Rural areas represent approximately 95% of the 14000 km(2) Alabama Black Belt, an area of widespread Vertisols dominated by clayey, smectitic, shrink-swell soils. These soils are unsuitable for conventional onsite wastewater treatment systems (OWTS) which are nevertheless widely used in this region. In order to provide an alternative wastewater dosing system, an experimental field moisture controlled subsurface drip irrigation (SDI) system was designed and installed as a field trial. The experimental system that integrates a seasonal cropping system was evaluated for two years on a 500-m(2) Houston clay site in west central Alabama from August 2006 to June 2008. The SDI system was designed to start hydraulic dosing only when field moisture was below field capacity. Hydraulic dosing rates fluctuated as expected with higher dosing rates during warm seasons with near zero or zero dosing rates during cold seasons. Lower hydraulic dosing in winter creates the need for at least a two-month waste storage structure which is an insurmountable challenge for rural homeowners. An estimated 30% of dosed water percolated below 45-cm depth during the first summer which included a 30-year historic drought. This massive volume of percolation was presumably the result of preferential flow stimulated by dry weather clay soil cracking. Although water percolation is necessary for OWTS, this massive water percolation loss indicated that this experimental system is not able to effective control soil moisture within its monitoring zone as designed. Overall findings of this study indicated that soil moisture controlled SDI wastewater dosing is not suitable as a standalone system in these Vertisols. However, the experimental soil moisture control system functioned as designed, demonstrating that soil moisture controlled SDI wastewater dosing may find application as a supplement to other wastewater disposal methods that can function during cold seasons. PMID:21621905

He, Jiajie; Dougherty, Mark; Shaw, Joey; Fulton, John; Arriaga, Francisco

2011-10-01

59

Hydraulic servo system increases accuracy in fatigue testing  

Science.gov (United States)

Hydraulic servo system increases accuracy in applying fatigue loading to a specimen under test. An error sensing electronic control loop, coupled to the hydraulic proportional closed loop cyclic force generator, provides an accurately controlled peak force to the specimen.

Dixon, G. V.; Kibler, K. S.

1967-01-01

60

Nonlinear modeling and identification of the electro-hydraulic control system of an excavator arm using BONL model  

Science.gov (United States)

Electro-hydraulic control systems are nonlinear in nature and their mathematic models have unknown parameters. Existing research of modeling and identification of the electro-hydraulic control system is mainly based on theoretical state space model, and the parameters identification is hard due to its demand on internal states measurement. Moreover, there are also some hard-to-model nonlinearities in theoretical model, which needs to be overcome. Modeling and identification of the electro-hydraulic control system of an excavator arm based on block-oriented nonlinear(BONL) models is investigated. The nonlinear state space model of the system is built first, and field tests are carried out to reveal the nonlinear characteristics of the system. Based on the physic insight into the system, three BONL models are adopted to describe the highly nonlinear system. The Hammerstein model is composed of a two-segment polynomial nonlinearity followed by a linear dynamic subsystem. The Hammerstein-Wiener(H-W) model is represented by the Hammerstein model in cascade with another single polynomial nonlinearity. A novel Pseudo-Hammerstein-Wiener(P-H-W) model is developed by replacing the single polynomial of the H-W model by a non-smooth backlash function. The key term separation principle is applied to simplify the BONL models into linear-in-parameters structures. Then, a modified recursive least square algorithm(MRLSA) with iterative estimation of internal variables is developed to identify the all the parameters simultaneously. The identification results demonstrate that the BONL models with two-segment polynomial nonlinearities are able to capture the system behavior, and the P-H-W model has the best prediction accuracy. Comparison experiments show that the velocity prediction error of the P-H-W model is reduced by 14%, 30% and 75% to the H-W model, Hammerstein model, and extended auto-regressive (ARX) model, respectively. This research is helpful in controller design, system monitoring and diagnosis.

Yan, Jun; Li, Bo; Guo, Gang; Zeng, Yonghua; Zhang, Meijun

2013-11-01

 
 
 
 
61

Hydraulic drives for control rods  

International Nuclear Information System (INIS)

Purpose: To improve the reliability of control rod drives by keeping the pipeway surface always dried thus to increase the life of the pipeways. Constitution: Water pressurized through a control rod driving water pump is heated to a constant temperature by a temperature adjusting device. The heated pressurized water is flown into a master control device, adjusted its pressure to a level required for each of the operations and sent to each of the hydraulic control units corresponding to control rod drives for the extraction and insertion of the control rods. Such temperature adjustment to the control rods driving water can avoid vapor condensation or the likes on the surface of the pipeways inside and outside of a reactor building due to temperature difference in winter and summer, so that no disadvantageous effects may be exerted on the pipeways. (Furukawa, Y.)

62

14 CFR 29.1435 - Hydraulic systems.  

Science.gov (United States)

...2010-01-01 2010-01-01 false Hydraulic systems. 29.1435 Section 29.1435 Aeronautics...Miscellaneous Equipment § 29.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows:...

2010-01-01

63

14 CFR 23.1435 - Hydraulic systems.  

Science.gov (United States)

...2010-01-01 2010-01-01 false Hydraulic systems. 23.1435 Section 23.1435 Aeronautics...Miscellaneous Equipment § 23.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows:...

2010-01-01

64

14 CFR 25.1435 - Hydraulic systems.  

Science.gov (United States)

...2010-01-01 2010-01-01 false Hydraulic systems. 25.1435 Section 25...Miscellaneous Equipment § 25.1435 Hydraulic systems. (a) Element design. Each element of the hydraulic system must be designed...

2010-01-01

65

14 CFR 27.1435 - Hydraulic systems.  

Science.gov (United States)

...2010-01-01 2010-01-01 false Hydraulic systems. 27.1435 Section 27.1435 Aeronautics...Equipment Safety Equipment § 27.1435 Hydraulic systems. (a) Design. Each hydraulic system and its elements must withstand,...

2010-01-01

66

Space Shuttle Upgrades Advanced Hydraulic Power System  

Science.gov (United States)

Three Auxiliary Power Units (APU) on the Space Shuttle Orbiter each provide 145 hp shaft power to a hydraulic pump which outputs 3000 psi hydraulic fluid to 41 hydraulic actuators. A hydrazine fuel powered APU utilized throughout the Shuttle program has undergone many improvements, but concerns remain with flight safety, operational cost, critical failure modes, and hydrazine related hazards. The advanced hydraulic power system (AHPS), also known as the electric APU, is being evaluated as an upgrade to replace the hydrazine APU. The AHPS replaces the high-speed turbine and hydrazine fuel supply system with a battery power supply and electric motor/pump that converts 300 volt electrical power to 3000 psi hydraulic power. AHPS upgrade benefits include elimination of toxic hydrazine propellant to improve flight safety, reduction in hazardous ground processing operations, and improved reliability. Development of this upgrade provides many interesting challenges and includes development of four hardware elements that comprise the AHPS system: Battery - The battery provides a high voltage supply of power using lithium ion cells. This is a large battery that must provide 28 kilowatt hours of energy over 99 minutes of operation at 300 volts with a peak power of 130 kilowatts for three seconds. High Voltage Power Distribution and Control (PD&C) - The PD&C distributes electric power from the battery to the EHDU. This 300 volt system includes wiring and components necessary to distribute power and provide fault current protection. Electro-Hydraulic Drive Unit (EHDU) - The EHDU converts electric input power to hydraulic output power. The EHDU must provide over 90 kilowatts of stable, output hydraulic power at 3000 psi with high efficiency and rapid response time. Cooling System - The cooling system provides thermal control of the Orbiter hydraulic fluid and EHDU electronic components. Symposium presentation will provide an overview of the AHPS upgrade, descriptions of the four hardware elements, and a summary of development results to date.

2004-01-01

67

49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.  

Science.gov (United States)

...means a device installed in a hydraulic brake system that reduces the operator...force to the brake control. Hydraulic brake system means a system that uses...except for vehicles using hydraulic system mineral oil. (C) If...

2010-10-01

68

49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.  

Science.gov (United States)

...a device installed in a hydraulic brake system that reduces the operator...to the brake control. Hydraulic brake system means a system that uses...except for vehicles using hydraulic system mineral oil. (C) If a...

2010-10-01

69

Optimal control: An effective method for designing hydraulic hybrid vehicles  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The full potential for fuel savings of hydraulic hybrid vehicles has yet to be realized due to a disconnect between controller design and system design. Previous research has only used optimal control to baseline control strategies as a means for creating better implementable controllers. However, the utility of optimal control extends well beyond controller design. This thesis merges this concept with system design, and in doing so prove the effectiveness of designing a hydraulic hybrid...

Cross, Michael A.

2011-01-01

70

Hydraulic drive system prevents backlash  

Science.gov (United States)

Hydraulic drive system uses a second drive motor operating at reduced torque. This exerts a relative braking action which eliminates the normal gear train backlash that is intolerable when driving certain heavy loads.

Acord, J. D.

1965-01-01

71

Hydraulic System Wear Debris Analysis.  

Science.gov (United States)

The use of Ferrography as a means to detect elastomer wear in aircraft hydraulic systems is explored. A method is described which increases the deposition of elastomer material on the Ferrogram. Nine distinct seal wear mechanisms are identified. Metallic ...

D. H. Ahlberg

1982-01-01

72

Design of active disturbance rejection controller for the hydraulic APC system of the rolling mill  

Science.gov (United States)

Considering uncertain external disturbance, the model of automatic position control system is established. Then, according to the information of input and output, using extended states observer (ESO), a newer observer is proposed to observe and compensate this integrated disturbance, and a controller is designed based on active disturbance rejection control (ADRC). This controller has very strong robustness not only to external disturbance, but also to unpredictable plant parameter variations.

Zhang, Ruicheng; Chen, Zhikun

2011-10-01

73

Flow Distribution in Hydraulic Systems  

Science.gov (United States)

General Flow Distribution Program analyzes pressure drops and flow distribution in closed and open hydraulic systems. Analyzes system on basis of incompressible flow though system may contain either compressible or incompressible fluid. Program solves fixed or variable flow problems for series, parallel, or series/parallel systems.

Nguyen, S. N.

1983-01-01

74

Synchronous control for the hydraulic width system of edger rolling mill  

Science.gov (United States)

Edger rolling mill is a load system in which the upper and the lower cylinder actuate a side vertical roller at the same time. Due to the linkage of the load, the output and control of two channels influence each other. Synchronic-control issue is discussed aim to the system with serious coupling. Neural network inverse as decoupling controller is proposed to account for the complicated process dynamics characterized by nonlinear, time-varying, uncertain and load couple properties. Firstly, the reversibility of the system is analyzed and the ANN inverse dynamic is constructed based on a feed forward and neural network structure with enlarged back propagation algorithm. Secondly, the system is changed into two pseudo-linear sub-system through connecting the controlled system and inverse dynamic model in series. Aim to two pseudo-linear sub-system pole assignments method is proposed to enhance the whole system performance. A series simulation was conducted and results showed the proposed controller does better than traditional PID not only on decoupling but also on the transient response, as well as robustness under vary conditions.

Ning, Shurong; Fan, Zhuoyu

2008-10-01

75

Electokinetic high pressure hydraulic system  

Science.gov (United States)

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

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

2000-01-01

76

Robust hydraulic position controller by a fuzzy state controller  

International Nuclear Information System (INIS)

In nuclear industry, one of the most important design considerations of controllers is their robustness. Robustness in this context is defined as the ability of a system to be controlled in a stable way over a wide range of system parameters. Generally the systems to be controlled are linearized, and stability is subsequently proven for this idealized system. By combining classical control theory and fuzzy set theory, a new kind of state controller is proposed and successfully applied to a hydraulic position servo with excellent robustness against variation of system parameters

77

Hydraulic Actuator for Ganged Control Rods  

Science.gov (United States)

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.

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

1986-01-01

78

Scaling behaviour of pressure driven micro hydraulic systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a lumped network approach for the modelling and design of micro-hydraulic systems. A hydraulic oscillator has been built consisting of hydraulic resistors, capacitors and transistors (pressure controlled valves). The scaling of micro-hydraulic networks consisting of linear resistors, capacitors and inertances has been studied. An important result is that to make smaller networks faster, driving pressures should increase with reducing size.

Tas, N. R.; Lammerink, T. S. J.; Berenschot, J. W.; Elwenspoek, M. C.; Berg, A. Den

2002-01-01

79

Assessment of the reliability of thermal-hydraulic and neutronics parameters of Ghana research reactor-1 control systems  

International Nuclear Information System (INIS)

The thermal-hydraulics and neutronics parameters of GHARR-1 control systems were assessed for its reliability after 18 years of operation using the Micro-Computer Closed Loop System (MCCLS) and original control Console (CC). The MCCLS and some components that control the sensitivity and the reading mechanism of the meters on the control systems have been replaced with new ones over the years, due to ageing, repairs and obsolescence. The results show that when reactor is operated at the different power levels the preset neutron fluxes at the control systems is 1.6 times the neutron fluxes obtained using a flux monitor at the inner irradiation site two of the reactor. The average percentage of deviation of fluxes from the actual preset was 36.5% which compares very well with the reactivity decrease of 36.3% after operating the reactor at critical neutron flux of 1.0 × 109n/cm2s. The reactivity regulators were adjusted to increase the core reactivity to 4 mk and the reactor operated at 15kW. The preset neutron flux at the control systems reduced to 1.07 times the Neutron fluxes obtained using a flux monitor at the inner irradiation site 2 of the reactor. The performance of the current micro - amplifiers in the two independent control instrumentations was assessed at an input current of 10µA. The results showed that the flux registered on both the CC and MCCLS varied by a factor of 1.2. The correlation between neutron flux and power, as well as temperature and power at transient state produced almost the same thermal power at about 20% above the rating power of 30 kW but deviated at lower and higher power ratings. The dynamic test through positive reactivity insertion, demonstrate or confirm the inherent safety of the reactor. (au)

80

Improvement of Hydraulic Edge Position Control System by Proportion Sliding Mode of Self-tuning Switching Gain  

Directory of Open Access Journals (Sweden)

Full Text Available Aiming at the problem of tracking performance degradation of hydraulic EPC system caused by time-varying inertia parameters, nonlinear and external disturbances, the proportion sliding mode control of fuzzy self-tuning gain was proposed. The EPC system state space model on deviation parameters was established and the main feedback sliding mode switching algorithm was designed. The fuzzy method was used to dynamically adjust the proportion sliding mode switching gain by product of the switching function and its derivative state and to adaptive compensate for the uncertainty of the system. At the same time to ensure the effectiveness of the design strategy, the controller model and physical model worked together to simulate the actual conditions. The fixed switching gain switch was, respectively greater and smaller and compared with the fuzzy self-tuning gain, in which the latter achieves a fast and coordinated control of chattering. The results show that after comprehensive consideration all interference the system is stable, fast response, high accuracy and to solve chattering problem caused by the traditional large switching gain of proportion sliding mode.

Jin Baoquan

2012-11-01

 
 
 
 
81

PLC Based Hydraulic Auto Ladle System  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper we have implemented a PLC based Hydraulic Auto Ladle System for Casting Department of Victory Precisions Pvt. Ltd. Chakan, Pune. This project work presents the study and design of PLC based Hydraulic Auto Ladle System. Aluminium pouring is the key process in Casting and Forging industry. Different products are manufactured by the company for automobile sector using aluminium. Programmable Logic Controller (PLC is used for the automation of pouring process. Automation is done to increase the accuracy and consistency in the quality of the product. Human errors, while pouring the aluminium, which in-turn results in defective production are eliminated by introducing automation.

Amogh Tayade

2014-03-01

82

Digital hydraulic valving system. [design and development  

Science.gov (United States)

The design and development are reported of a digital hydraulic valving system that would accept direct digital inputs. Topics include: summary of contractual accomplishments, design and function description, valve parameters and calculations, conclusions, and recommendations. The electrical control circuit operating procedure is outlined in an appendix.

1973-01-01

83

A study on reliability of electro-hydraulic governor control system for large steam turbine in power plant  

International Nuclear Information System (INIS)

In this work, the right management procedure for hydraulic power oil will be discussed and suggested. A thermal power plant turbine should respond to the change of load status. However, to satisfy the frequency of alternating current, the revolution per minute should be kept constant. Therefore, by controlling the flow rate of the steam to the turbine, the governor satisfies the load variation without alternating the revolution per minutes of the turbine. To protect the governor, the hydraulic power unit should be managed carefully by controlling the quality and the flow rate of the oil

84

Precision Force Control for an Electro-Hydraulic Press Machine  

Directory of Open Access Journals (Sweden)

Full Text Available This thesis is primarily intended to design a PC-based control system to control the force of an electro-hydraulic servo press system for implementing precision force control. The main feature is to develop a composite control by using the relief valve and the flow servo valve. Using feedback from a force sensor, a fuzzy controller was designed with LabVIEW software as the system control core for achieving a precision force control for the hydraulic cylinder on its travel and output. The weakness of hydraulic systems is that hydraulic oil is compressible and prone to leaking, and its characteristics can vary with oil temperature, thus making it difficult for a general linear controller to achieve accurate control. Therefore, a fuzzy controller was designed with LabVIEW along with a NI-PCI_6221 interface card and a load cell to control the servo valve flow and the relief valve to control the pressure source. The testing results indicate that accurate force control output of an electro-hydraulic servo press system can be obtained.

Hong-Ming Chen

2014-08-01

85

Development of hydraulic brake actuator for active brake control; Active brake seigyoyo yuatsu booster no kaihatsu  

Energy Technology Data Exchange (ETDEWEB)

Recently, application of active brake control systems of the vehicle are increasing. (Vehicle stability control, Panic brake assist ) We have developed a new hydraulic brake actuator for active brake control systems. New hydraulic brake actuator is composed of the three parts. (Hydraulic booster unit, Power supply unit, Control valve unit) This report describes the construction of the new hydraulic booster unit. 2 refs., 10 figs.

Konishi, Y.; Hattori, M. Sugisawa, M.; Nishii, M. [Aisin Seiki Co. Ltd., Aichi (Japan)

1997-10-01

86

Experimental evaluation of control strategies for hydraulic servo robot  

DEFF Research Database (Denmark)

In this paper different linear and non-linear controllers applied to a hydraulically driven servo robot are evaluated and validated. The task is to make the actuators of the manipulator track a position reference with minimum error. Hydraulic systems are intrinsically non-linear and using linear control techniques typically results in conservatively dimensioned controllers to obtain stable performance. Non-linear control techniques have the potential of overcoming these problems and in this paper the focus is on applying simple nonlinear robust and adaptive controllers feasible for implementation in industrial servo drives. The different controllers are compared and evaluated from simulation and experimental results.

Bech, Michael MŘller; Andersen, Torben Ole

2013-01-01

87

Modified hydraulic braking system limits angular deceleration to safe values  

Science.gov (United States)

Conventional spring actuated, hydraulically released, fail-safe disk braking system is modified to control the angular deceleration of a massive antenna. The hydraulic system provides an immediate preset pressure to the spring-loaded brake shoes and holds it at this value to decelerate the antenna at the desired rate.

Briggs, R. S.; Council, M.; Green, P. M.

1966-01-01

88

X-15 hydraulic-system development  

Science.gov (United States)

Despite the exacting requirements and conditions of the X-15 including much higher temperature, high horsepower, and extreme vibration and duty cycles, the hydraulic flight control systems compare favorably, weightwise, with preceding models. Although some items, such as the pumps, are heavier, the total system, excluding actuators, weighs approximately 195 pounds as compared with 196 pounds for the F-107A airplane. Use of the new piggy-back pump, with its low flow during most of the operating time, also permitted a reduction in fluid capacity of the hydraulic reservoirs and the total systems, even though the volume of some of the actuators is quite large. This effected a considerable saving in fluid weight. Complete ground-support equipment is available and this equipment, as well as the airplane systems, contains means for complete 5- to 15- micron filtration under controlled temperature conditions. By use of advanced engineering techniques and extensive laboratory testing, it has been possible to provide a sound, lightweight hydraulic system for this advanced, high-performance airplane. (author)

Culleton, R J

1958-01-01

89

Case study -- Hydraulic control via induced dilution  

Energy Technology Data Exchange (ETDEWEB)

Ground water investigations within the shallow flow system at the Laidlaw Environmental Services Secure Landfill facility in Corunna, Ontario, identified the presence of chloride at elevated concentrations (> 100 mg/L) in shallow subsurface soils immediately adjacent to an area collectively referred to as the pre-1986 landfill area. Typical background chloride concentrations in the area are in the range of 40 mg/L to 60 mg/L. It is documented that chloride is moving with ground water preferentially through fractures within the upper 3 to 5 meters of the clayey silt till which underlies the site. The waste cells in the area extend up to 5 meters above original ground surface with ground water/chloride movement driven by a leachate mound developed within the entombed waste. Diffusion of chloride into the till matrix from the fractures is also occurring resulting in a chloride enriched zone downgradient of the landfill in close proximity of the eastern and southern property boundaries. In response to these findings, Laidlaw is evaluating a promising remedial technology to prevent or minimize the off-site movement of chloride impacted ground water from the pre-1986 landfill area. A hydraulic control structure comprised of three separate trench configurations was constructed downgradient of the pre-1986 landfill area and was operated in both an injection mode, to form a ground water mound or flow barrier, and in a recovery mode to depress the ground water table and induce movement of the ground water/chloride to the control structure for subsequent collection and treatment. Preliminary results indicate that an in-situ, low cost, semi-passive remedial system can be implemented whereby clean water is introduced along a shallow trench to provide a hydraulic barrier/ground water mixing zone that will effectively reduce the chloride concentration in the ground water to levels acceptable for off-site movement.

Arsenault, J.A.; Funk, G.H. [Gartner Lee Ltd., St. Catharines, Ontario (Canada)

1997-12-31

90

Replacing hydraulic components in gas and steam turbine protection and control systems with electrical systems; Turbinenschutz und -regelung an Gas- und Dampfturbinen. Austausch von hydraulischen Komponenten gegen elektrische Systeme  

Energy Technology Data Exchange (ETDEWEB)

In the past, technical facilities and especially power plants relied almost exclusively on hydraulic components. Some factors have prompted a trend to modernise protection and control systems and replace hydraulic devices with electric or electronic components. The scope of these measures varies from plant to plant and depends on general requirements and the specific needs and wishes of the operator. This article explains how these retrofit projects can be standardised, covering all aspects from the design, installation and commissioning of the new systems through to operator training and subsequent servicing across different disciplines. (orig.)

Nierade, Guido; Linde, Michael van de; Mueller, Detlef [E.ON Anlagenservice GmbH, Gelsenkirchen (Germany). Rotierende Komponenten

2010-07-01

91

Modelling and control of a high performance electro-hydraulic test bench  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Hydraulic systems are widely applied in industry for position or force control. However, due to hydraulic system nonlinearities, it is difficult to achieve a precise model valid over a large range of frequencies and movements. The work in this dissertation focuses on a high performance hydraulic test bench which involves three main hydraulic components, i.e. two high performance servovalves, a double rod actuator, and a specific intermediate block connecting the servovalves and actuator. This...

Xu, Yaozhong

2013-01-01

92

49 CFR 570.55 - Hydraulic brake system.  

Science.gov (United States)

... 2010-10-01 false Hydraulic brake system. 570.55 Section 570...000 Pounds § 570.55 Hydraulic brake system. The following requirements apply to vehicles with hydraulic brake systems. (a) Brake system...

2010-10-01

93

Model Reference PID Control of an Electro-hydraulic Drive  

Directory of Open Access Journals (Sweden)

Full Text Available Hydraulic cranes are inherently nonlinear and contain components exhibiting strong friction, saturation, variable inertia mechanical loads, etc. The characteristics of these non-linear components are usually not known exactly as structure or parameters. For these reasons, tuning of the traditional PID controller parameters to control this system for the required performance faces a strong challenge. In this paper a new approach to design an adaptive PID control has the ability to solve the control problem of highly nonlinear systems such as the hydraulic crane was proposed. The core of the design method depends on comparing the performance of the Model Reference (MR response with the nonlinear model response and feeding an adaptation signal to the PID control system to eliminate the error in between. It is found that the proposed MR-PID control policy provided the most consistent performance in terms of rise time and settling time regardless of the nonlinearities.

Ayman A. Aly

2012-10-01

94

Simulation and control of an electro-hydraulic actuated clutch  

Science.gov (United States)

The basic function of any type of automotive transmission is to transfer the engine torque to the vehicle with the desired ratio smoothly and efficiently and the most common control devices inside the transmission are clutches and hydraulic pistons. The automatic control of the clutch engagement plays a crucial role in Automatic Manual Transmission (AMT) vehicles, being seen as an increasingly important enabling technology for the automotive industry. It has a major role in automatic gear shifting and traction control for improved safety, drivability and comfort and, at the same time, for fuel economy. In this paper, a model for a wet clutch actuated by an electro-hydraulic valve used by Volkswagen for automatic transmissions is presented. Starting from the developed model, a simulator was implemented in Matlab/Simulink and the model was validated against data obtained from a test-bench provided by Continental Automotive Romania, which includes the Volkswagen wet clutch actuated by the electro-hydraulic valve. Then, a predictive control strategy is applied to the model of the electro-hydraulic actuated clutch with the aims of controlling the clutch piston displacement and decreasing the influence of the network-induced delays on the control performances. The simulation results obtained with the proposed method are compared with the ones obtained with different networked controllers and it is shown that the strategy proposed in this paper can indeed improve the performances of the control system.

Balau, Andreea-Elena; Caruntu, Constantin-Florin; Lazar, Corneliu

2011-08-01

95

14 CFR 33.72 - Hydraulic actuating systems.  

Science.gov (United States)

... 2010-01-01 2010-01-01 false Hydraulic actuating systems. 33.72 Section 33...Construction; Turbine Aircraft Engines § 33.72 Hydraulic actuating systems. Each hydraulic actuating system must function...

2010-01-01

96

49 CFR 570.55 - Hydraulic brake system.  

Science.gov (United States)

...2010-10-01 2010-10-01 false Hydraulic brake system. 570.55 Section...Than 10,000 Pounds § 570.55 Hydraulic brake system. The following requirements apply to vehicles with hydraulic brake systems. (a) Brake...

2010-10-01

97

14 CFR 33.72 - Hydraulic actuating systems.  

Science.gov (United States)

...2010-01-01 2010-01-01 false Hydraulic actuating systems. 33.72 Section 33.72 Aeronautics...Turbine Aircraft Engines § 33.72 Hydraulic actuating systems. Each hydraulic actuating system must function properly under...

2010-01-01

98

Hydraulically actuated fuel injector including a pilot operated spool valve assembly and hydraulic system using same  

Science.gov (United States)

The present invention relates to hydraulic systems including hydraulically actuated fuel injectors that have a pilot operated spool valve assembly. One class of hydraulically actuated fuel injectors includes a solenoid driven pilot valve that controls the initiation of the injection event. However, during cold start conditions, hydraulic fluid, typically engine lubricating oil, is particularly viscous and is often difficult to displace through the relatively small drain path that is defined past the pilot valve member. Because the spool valve typically responds slower than expected during cold start due to the difficulty in displacing the relatively viscous oil, accurate start of injection timing can be difficult to achieve. There also exists a greater difficulty in reaching the higher end of the cold operating speed range. Therefore, the present invention utilizes a fluid evacuation valve to aid in displacement of the relatively viscous oil during cold start conditions.

Shafer, Scott F. (Morton, IL)

2002-01-01

99

Hydraulics  

Science.gov (United States)

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

2011-01-03

100

Control of a large hydraulic manipulator for decommissioning tasks  

International Nuclear Information System (INIS)

A large hydraulic manipulator has been enhanced as a carrier system for decommissioning tools. The enhancements included mechanical modifications, selection and adaption of sensor equipment and control system development. Experiments on a non contaminated test site have taken place in fall 1992. These experiments confirmed the viability of the concept. Work remains to be done in the area of radiation hardening of the components, automation of the tool exchange and automatic performance of decommissioning tasks

 
 
 
 
101

Computerized hydraulic scanning system for quantitative non destructive examination  

International Nuclear Information System (INIS)

A hydraulic scanning system with five degrees of freedom is described. It is primarily designed as a universal system for fast and accurate ultrasonic inspection of materials for their internal variation in properties. The whole system is controlled by a minicomputer which also is used for evaluating and presenting of the results of the inspection. (author)

102

A coupled analysis of system thermal-hydraulics and three-dimensional reactor kinetics for a 12-finger control element assembly drop event in a PWR plant  

International Nuclear Information System (INIS)

A coupled system thermal-hydraulics (T-H) and three-dimensional reactor kinetics code, MARS/MASTER, was developed to attain more accurate predictions for nuclear system transients that involve strong interactions between neutronic and T-H phenomena. In this paper, a 12-finger control element assembly (CEA) drop event in a two-loop pressurized water reactor (PWR) plant under a full power condition was analyzed, where the 12-finger CEA that is nearest to the hot leg of Loop 2 is assumed to incidentally drop. This instantaneously results in an asymmetric radial power distribution and, in turn, asymmetric loop behavior, which may lead to a reactor trip due to a low departure from nucleate boiling (DNB) ratio at the intact side of the core or an excessive difference between the cold leg coolant temperatures. This event clearly requires a coupled calculation of system T-H and three-dimensional reactor kinetics to realistically investigate the thermal-hydraulic behavior of the reactor core. A simple theoretical modeling is also devised to evaluate the cold leg temperature difference under a quasi-steady state.

103

Optimal control based design of output coupled power split hydraulic hybrid  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Hydraulic hybrid power trains/vehicles (HHV) achieve higher power density, better utilization of regenerative braking due to faster storage of brake energy in hydraulic accumulators, much lower installation cost and no recycling problems compared to its electric counterpart. The goal of this thesis is to investigate the potential of fuel savings of hydraulic hybrid power trains compared to electric hybrid vehicles. This thesis utilizes optimal control for both system design and control. As a ...

Zhao, Minming

2012-01-01

104

Adaptive Sliding Mode Control for Hydraulic Drives : A New Approach  

DEFF Research Database (Denmark)

This paper presents a new adaptive sliding mode controller generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD’s). The proposed control scheme requires limited knowledge on system parameters, and employs only piston- and valve spool position feedback. The main target is to overcome problems with linear controllers deteriorating performance due to the inherent nonlinear nature of such systems, without requiring extensive knowledge on system parameters nor advanced control theory. In order to accomplish this task, an integral sliding mode controller employing parameter adaption through a recursive algorithm is presented. This is based on a reduced order model approximation of a VCD with unmatched valve flow- and cylinder asymmetries. Bounds on parameters are obtained despite lack of parameter knowledge, and the proposed controller demonstrates improved position tracking performance and robustness / adaptability compared with a conventional feedforward-PI controller, when subjected to perturbations in supply pressure and coulomb friction.

Schmidt, Lasse; Andersen, Torben Ole

2013-01-01

105

The modern instrumentation used for monitoring and controlling the main parameters of the regenerative electro-mechano-hydraulic drive systems  

Science.gov (United States)

In this work is presented the modern instrumentation used for monitoring and controlling the main parameters for one regenerative drive system, used to recovering the kinetic energy of motor vehicles, lost in the braking phase, storing and using this energy in the starting or accelerating phases. Is presented a Romanian technical solution for a regenerative driving system, based on a hybrid solution containing a hydro-mechanic module and an existing thermal motor drive, all conceived as a mechatronics system. In order to monitoring and controlling the evolution of the main parameters, the system contains a series of sensors and transducers that provide the moment, rotation, temperature, flow and pressure values. The main sensors and transducers of the regenerative drive system, their principal features and tehnical conecting solutions are presented in this paper, both with the menaging electronic and informational subsystems.

Cristescu, Corneliu; Drumea, Petrin; Krevey, Petrica

2009-01-01

106

Hydraulic Motor Driving Variable-Pitch System for Wind Turbine  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The present hydraulic variable-pitch mechanism of wind turbine uses three hydraulic cylinders to drive three crank and connecting rod mechanisms respectively; the blades are moved with the cranks. The hydraulic variable-pitch mechanism has complex structure, occupies a lot of space and its maintenance is trouble. In order to make up for the shortcomings of hydraulic cylinder variable-pitch system, the present hydraulic variable-pitch mechanism should be changed as follows: hydraulic motors ar...

Huang, Ye; Qi, Jibao

2013-01-01

107

Hydraulic control device for control rod drives  

International Nuclear Information System (INIS)

Purpose: To enable control rod insertion and extraction in a predetermined time with no effects from pressure variations in the reactor. Constitution: The pressure conditions in the reactor are detected by a pressure generator and the detected value is inputted to a pressure compensator. An adequate signal corresponding to the changes in the flow rate resulted from the changes in the reactor pressure is set and compensated in the pressure compensator. The proportional gain in a flow rate indication regulator is thus made pressure-dependent and the total gain can be obtained always at a certain level irrespective of the reactor pressure. (Ikeda, J.)

108

Tracking control of the hydraulically actuated flexible manipulator  

International Nuclear Information System (INIS)

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

109

Thermal Equilibrium of a Hydraulic Driving System  

Directory of Open Access Journals (Sweden)

Full Text Available To put into evidence the consequence of the energetic losses that appears in a hydraulic driving systems and to evaluate how does the system performance and reliability are strongly affected by the temperature increase due-to the flowing fluid, in this study a thermal analysis is presented for improving the possibility of developing a practical and simplified method for establishing the optimum working temperature at any instant time. Focus is on computational methods that to be used for controlling the working temperature around the limit of admissible temperature, if the working temperature exceeds this limit, the fluid properties alteration will occur rapidly and a slow deterioration in the internal working parts of the system is expected, based on the failure rule rate that doubles for every 10?C of a temperature increase. Heat load duration is evaluated for both short and long operation periods, in which thermal equations are introduced to describe the conduction, convection and radiation modes of the heat transfer for the given mode of operation .The main conclusion of this study draws an important attention, that must be taken into account even during the first stages of designing such systems, in order to establish the optimum dimensions for the heat exchanger solution, as a design option when required for reducing the heat load for satisfying the needed working temperature and then keeping the system within the energy balance condition

Tarawneh S. Muafag

2004-01-01

110

Nonelastomeric Rod Seals for Advanced Hydraulic Systems  

Science.gov (United States)

Advanced high temperature hydraulic system rod sealing requirements can be met by using seals made of nonelastomeric (plastic) materials in applications where elastomers do not have adequate life. Exploratory seal designs were optimized for advanced applications using machinable polyimide materials. These seals demonstrated equivalent flight hour lives of 12,500 at 350 F and 9,875 at 400 F in advanced hydraulic system simulation. Successful operation was also attained under simulated space shuttle applications; 96 reentry thermal cycles and 1,438 hours of vacuum storage. Tests of less expensive molded plastic seals indicated a need for improved materials to provide equivalent performance to the machined seals.

Hady, W. F.; Waterman, A. W.

1976-01-01

111

Experimental Verification of Fault Predictions in High Pressure Hydraulic Systems  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper a model of a high pressure hydraulic system was developed to simulate the effect of increased internal leakages inside the hydraulic cylinder and the 4/2 way directional control valve and to calculate the main parameters of the hydraulic system under various loads through the use of leakage-simulating throttle valves. After the completion of modeling, the throttle valves that simulate the internal leakages were calibrated and a number of test runs were performed for the cases of normal operation and the operation with increased internal leakages. The theoretical predictions were compared against the experimental results from an actual hydraulic test platform installed in the laboratory. In all cases, modeling and experimental data curves correlate very well in form, magnitude and response times for all the system’s main parameters. This proves that the present modeling can be used to accurately predict various faults in hydraulic systems, and can thus be used for proactive fault finding in many cases, especially when the defective component is not easily detected and obvious at first sight.

P. Athanasatos

2014-05-01

112

Hydraulics.  

Science.gov (United States)

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

Decker, Robert L.; Kirby, Klane

113

Lightweight Hydraulic System Hardware Endurance Test.  

Science.gov (United States)

A 100 hour endurance test was conducted at 8000 psi and +200F on lightweight hardware in a laboratory hydraulic system designed to be representative of aircraft-type circuitry. The hardware cycled were: pump, relief valve, restrictors, solenoid valves, fl...

J. N. Demarchi, R. K. Haning

1975-01-01

114

Dynamic behavior of upper hydraulic drive control rod  

International Nuclear Information System (INIS)

200 MW nuclear heating reactor (NHR) is developed based on 5 MW testing heating reactor (THR-5). If 200 MW NHR is constructed as commercial demonstration reactor, it will be used as heat source for desalination or urban heat supply. In order to improve its economics INET has been optimized its structure design. The upper hydraulic drive control rod just is the optimization result. the control rod drive is located at the upper part of reactor core, the fuel rod in each corner of the bundle will not be removed as THR-5. In order to investigate the dynamic behavior of the upper control rod driving system, the method of characteristics based on solving the equations of continuity and momentum is used. The mathematical model includes all component modules (pump, valve, impulse cylinder, drive cylinder, etc.). The typical actions of control rod, withdraw, insertion and scram with relation to the parameters of driving system are studied sufficiently. The variation of physical parameters will lead to vary of dynamic behavior of control rod certainly. The temperature characteristic of hydraulic drive control rod is important on its reliable operating. This paper will this question and obtain the reasonable design parameters. (authors)

115

Reactor Shutdown Mechanism by Top-mounted Hydraulic System  

Energy Technology Data Exchange (ETDEWEB)

There are two types of reactor shutdown mechanisms in HANARO. One is the mechanism driven by a hydraulic system, and the other is driven by a stepping motor. In HANARO, there are four Control Rod Drive Mechanisms (CRDMs) with an individual step motor and four Shutoff (SO) Units with an individual hydraulic system located at the top of reactor pool. The absorber rods in SO units are poised at the top of the core by the hydraulic force during normal operation. The rods of SO units drop by gravity as the first reactor showdown mechanism when a trip is commended by the reactor protection system (RPS). The rods in CRDMs also drop by gravity together as a redundant shutdown mechanism. When a trip is commended by the reactor regulating system (RRS), the absorber rods of CRDM only drop; while the absorber rods of SO units stay at the top of the core by the hydraulic system. The reactivity control mechanisms of in JRTR, one of the new research reactor with plate type fuels, consist of four CRDMs driven by an individual step motor and two second shutdown drive mechanisms (SSDMs) driven by an individual hydraulic system as shown in Fig. 1. The CRDMs act as the first reactor shutdown mechanism and reactor regulating as well. The top-mounted SSDM driven by the hydraulic system for the JRTR is under design in KAERI. The SSDM provides an alternate and independent means of reactor shutdown. The second shutdown rods (SSRs) of the SSDM are poised at the top of the core by the hydraulic system during the normal operation and drop by gravity for the reactor trip. Based on the proven technology of the design, operation and maintenance for HANARO, the SSDM for the JRTR has been optimized by the design improvement from the experience and test. This paper aims for the introduction of the SSDM in the process of the basic design. The major differences of the shutdown mechanisms by the hydraulic system are compared between HANARO and JRTR, and the design features, system, structure and future works are also described

Kim, Sang Haun; Cho, Yeong Garp; Choi, Myoung Hwan; Lee, Jin Haeng; Huh, Hyung; Kim, Jong In [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2012-05-15

116

Vehicle hydraulic system that provides heat for passenger compartment  

Science.gov (United States)

A vehicle includes a vehicle housing which defines a passenger compartment. Attached to the vehicle housing is a hydraulic system, that includes a hydraulic fluid which flows through at least one passageway within the hydraulic system. Also attached to the vehicle housing is a passenger compartment heating system. The passenger compartment heating system includes a heat exchanger, wherein a portion of the heat exchanger is a segment of the at least one passageway of the hydraulic system.

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

2001-01-01

117

Micromachined hydraulic astable multivibrator  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The paper presents a hydraulic astable multivibrator system. The system consists of hydraulic resistors, hydraulic capacitors and hydraulic pressure controlled valves. The system is designed, realised and tested. The measured system behaviour agrees well with the model simulations. The free running frequency of the multivibrator is 0.18 Hz and the output pressure swing is 90% of the supply pressure.

Lammerink, T. S. J.; Tas, N. R.; Berenschot, J. W.; Elwenspoek, M. C.; Fluitman, J. H. J.

1995-01-01

118

D2O system and oil hydraulic system of fuelling machine  

International Nuclear Information System (INIS)

Two of the most important supporting systems in CANDU fuel handling system--D2O supply and control system and oil hydraulic system are described, focusing on design requirements, major function, system structure and the main work flow of the two systems individually so as to briefly and concisely present the two typical CANDU systems

119

Hydraulic system for a ratio change transmission  

Science.gov (United States)

Disclosed is a drive assembly (10) for an electrically powered vehicle (12). The assembly includes a transaxle (16) having a two-speed transmission (40) and a drive axle differential (46) disposed in a unitary housing assembly (38), an oil-cooled prime mover or electric motor (14) for driving the transmission input shaft (42), an adapter assembly (24) for supporting the prime mover on the transaxle housing assembly, and a hydraulic system (172) providing pressurized oil flow for cooling and lubricating the electric motor and transaxle and for operating a clutch (84) and a brake (86) in the transmission to shift between the two-speed ratios of the transmission. The adapter assembly allows the prime mover to be supported in several positions on the transaxle housing. The brake is spring-applied and locks the transmission in its low-speed ratio should the hydraulic system fail. The hydraulic system pump is driven by an electric motor (212) independent of the prime mover and transaxle.

Kalns, Ilmars (Northville, MI)

1981-01-01

120

Hydraulic Press with LS System for Modelling of Plastic Working Operations  

Directory of Open Access Journals (Sweden)

Full Text Available At first, the paper describes destination of the presented hydraulic press. Next, the substance of load sensing (LS systems’ operation was introduced, and electro-hydraulic system of this type, installed in laboratory hydraulic press, was described. The control and measurement circuit of the device was also described, and exemplary test results obtained during plastic working operations on soft non-ferrous alloys were presented.

Janusz Pluta

2008-03-01

 
 
 
 
121

Simulation of Dynamics of System with Hydraulic Lines and Linear Hydraulic Motor with Mass Load  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper deals with the numerical simulation of dynamic properties of the system consisting of hydraulic lines and linear hydraulic motor with a mass load. The mathematical model is created using Matlab SimHydraulics software. Oil bulk modulus, elasticity and volumes of pipes and hoses play a significant role in this case. Mathematical models are verified on experimental equipment. Pressure and position responses during sudden stop of a moving cylinder are measured on this equipment.

Vašina M.; Hružík L.; Bure?ek A.

2013-01-01

122

Simulation of Dynamics of System with Hydraulic Lines and Linear Hydraulic Motor with Mass Load  

Directory of Open Access Journals (Sweden)

Full Text Available This paper deals with the numerical simulation of dynamic properties of the system consisting of hydraulic lines and linear hydraulic motor with a mass load. The mathematical model is created using Matlab SimHydraulics software. Oil bulk modulus, elasticity and volumes of pipes and hoses play a significant role in this case. Mathematical models are verified on experimental equipment. Pressure and position responses during sudden stop of a moving cylinder are measured on this equipment.

Vašina M.

2013-04-01

123

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

Science.gov (United States)

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

Human Engineering Inst., Cleveland, OH.

124

Rubber seals for fluid and hydraulic systems  

CERN Document Server

Rubber Seals for Fluid and Hydraulic Systems is a comprehensive guide to the manufacturing and applications of rubber seals, with essential coverage for industry sectors including aviation, oil drilling and the automotive industry. Fluid leakage costs industry millions of dollars every year. In addition to wasted money, unattended leaks can result in downtime, affect product quality, pollute the environment, and cause injury. Successful sealing involves containment of fluid within a system while excluding the contaminants; the resilience of rubber enables it to be used to achi

Chandrasekaran, Chellappa

2009-01-01

125

Subsea BOP (Blowout Preventor) stack control system  

Energy Technology Data Exchange (ETDEWEB)

An improvement is provided in a system for controlling a subsea blowout preventer (BOP) whose functions are operated by a hydraulic control system. The improvement resides in a control system which has at least two elements and at least one back up control system. The control system includes a subsea pressure compensated reservoir for replenishing the supply of hydraulic fluid, and an electric motor, supplied with electrical command energy from the surface, to operate a hydraulic pump which operates in conjunction with the BOP hydraulic control system. One back up control system is a standby second electric motor, supplied with electrical command energy from the surface, to operate a hydraulic pump which operates in conjunction with the BOP hydraulic control system. A second back up control system is an acoustical unit including a transducer and a subsea acoustic receiver to operate the BOP hydraulic control system drawing hydraulic fluid from the subsea hydraulic accumulators associated with the hydraulic control system. Having two back up, standby systems, enhances the reliability of the BOP control. The total hydraulic control system is housed in a pressure compensated reservoir located at the usual pod locations. Two pods are used for additional redundancy.

Anand, R.; Trosin, D.; Gregov, B.; Holyk, R.D.; Margarit, R.; Stockdale, K.; Watson, J.

1988-07-12

126

Climate, vegetation, and soil controls on hydraulic redistribution in shallow tree roots  

Science.gov (United States)

Hydraulic redistribution defined as the translocation of soil moisture by plant root systems in response to water potential gradients is a phenomenon widely documented in different climate, vegetation, and soil conditions. Past research has largely focused on hydraulic redistribution in deep tree roots with access to groundwater and/or winter rainfall, while the case of relatively shallow (i.e., ?1-2 m deep) tree roots has remained poorly investigated. In fact, it is not clear how hydraulic redistribution in shallow root zones is affected by climate, vegetation, and soil properties. In this study, we developed a model to investigate the climate, vegetation, and soil controls on the net direction and magnitude of hydraulic redistribution in shallow tree root systems at the growing season to yearly timescale. We used the model to evaluate the effect of hydraulic redistribution on the water stress of trees and grasses. We found that hydraulic lift increases with decreasing rainfall frequency, depth of the rooting zone, root density in the deep soil and tree leaf area index; at the same time for a given rainfall frequency, hydraulic lift increases with increasing average rainstorm depth and soil hydraulic conductivity. We propose that water drainage into deeper soil layers can lead to the emergence of vertical water potential gradients sufficient to explain the occurrence of hydraulic lift in shallow tree roots without invoking the presence of a shallow water table or winter precipitation. We also found that hydraulic descent reduces the water stress of trees and hydraulic lift reduces the water stress of grass with important implications on tree-grass interactions.

Yu, Kailiang; D'Odorico, Paolo

2014-04-01

127

Reactor control system  

International Nuclear Information System (INIS)

The proposal relates to the improvement of a hydraulically controllable system for a nuclear reactor which ensures both safe shutdown in case of a coolant flow failure and easy handling in operation. The reactor contains a number of oblong tubes, some sections of which are located within the reactor core, others above it. Each of these tubes is filled with spherical absorption bodies up to a certain level, thus constituting a hydraulically supported stacked bed. The invention relates to the arrangement of secondary flow paths and the design of the oblong tubes which allow hydraulic control to be exercised as a function of reactor operation. (UWI)

128

Failure Prevention of Hydraulic System Based on Oil Contamination  

Science.gov (United States)

Oil contamination is the major source of failure and wear of hydraulic system components. As per literature survey, approximately 70 % of hydraulic system failures are caused by oil contamination. Hence, to operate the hydraulic system reliably, the hydraulic oil should be of perfect condition. This requires a proper `Contamination Management System' which involves monitoring of various parameters like oil viscosity, oil temperature, contamination level etc. A study has been carried out on vehicle mounted hydraulically operated system used for articulation of heavy article, after making the platform levelled with outrigger cylinders. It is observed that by proper monitoring of contamination level, there is considerably increase in reliability, economy in operation and long service life. This also prevents the frequent failure of hydraulic system.

Singh, M.; Lathkar, G. S.; Basu, S. K.

2012-07-01

129

Borehole hydraulic coal mining system analysis  

Science.gov (United States)

The borehole hydraulic coal mining system accesses the coal seam through a hole drilled in the overburden. The mining device is lowered through the hole into the coal seam where it fragments the coal with high pressure water jets which pump it to the surface as a slurry by a jet pump located in the center of the mining device. The coal slurry is then injected into a pipeline for transport to the preparation plant. The system was analyzed for performance in the thick, shallow coal seams of Wyoming, and the steeply pitching seams of western Colorado. Considered were all the aspects of the mining operation for a 20-year mine life, producing 2,640,000 tons/yr. Effects on the environment and the cost of restoration, as well as concern for health and safety, were studied. Assumptions for design of the mine, the analytical method, and results of the analysis are detailed.

Floyd, E. L.

1977-01-01

130

MONITORING INTENSE THE DEFORMED CONDITION HYDRAULIC ENGINEERING CONSTRUCTIONS MELIORATIVE SYSTEMS ?????????? ??????????-???????????????? ????????? ???????????????? ?????????? ????????????? ??????  

Directory of Open Access Journals (Sweden)

Full Text Available Results of operational monitoring are given is long maintained GTS of meliorative systems with nondestructive control methods. Possibility of use of devices of nondestructive control is especially noted at inspection of hydraulic engineering constructions, on an example of water carrying out channels that allows operatively, without additional damages, to receive an objective assessment of their technical condition. When using this approach, there is a possibility justification of parameters of defects and damages, which is impossible to establish at visual survey. The program complex for modeling of a technical condition of holding channels for calculation of predicted term of their service is also presented

Volosoukhin V. A.

2012-04-01

131

Fundamental Research on Hydraulic Systems Driven by Alternating Flow  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a new approach to rotary hydraulic systems, and the functional principles of rotary hydraulic systems that can work using alternating flows. Hydraulic transmissions using alternating flows are based on bidirectional displacement of a predefined volume of fluid through the connection pipes between the alternating flow, the pressure energy generator and the motor. The paper also presents some considerations regarding the basic calculation formulas, the design and testing pri...

Ioan-Lucian Marcu; Daniel-Vasile Banyai

2012-01-01

132

Hydraulic braking system for loads subjected to impacts and vibrations  

International Nuclear Information System (INIS)

This invention concerns a hydraulic braking system for loads subjected to impacts and vibrations. These double acting telescopic type hydraulic braking systems possess significant drawbacks linked to possibly important hydraulic leaks due to (a) the use of many dynamic seals in such appliances and (b) the effects of the environment of the system on these seals, particularly when employed in nuclear power stations where the seals reach significant temperatures and are subjected to radiation. Under this invention a remedy is suggested to such drawbacks by integrating means to offset automatically the leaks and the accumulation of hydraulic fluid expansions, as well as facilities to show if such leaks have occurred

133

System for Continuous Deaeration of Hydraulic Oil  

Science.gov (United States)

A system for continuous, rapid deaeration of hydraulic oil has been built to replace a prior system that effected deaeration more slowly in a cyclic pressure/ vacuum process. Such systems are needed because (1) hydraulic oil has an affinity for air, typically containing between 10 and 15 volume percent of air and (2) in the original application for which these systems were built, there is a requirement to keep the proportion of dissolved air below 1 volume percent because a greater proportion can lead to pump cavitation and excessive softness in hydraulic-actuator force-versus-displacement characteristics. In addition to overcoming several deficiencies of the prior deaeration system, the present system removes water from the oil. The system (see figure) includes a pump that continuously circulates oil at a rate of 10 gal/min (38 L/min) between an 80-gal (303-L) airless reservoir and a tank containing a vacuum. When the circulation pump is started, oil is pumped, at a pressure of 120 psi (827 kPa), through a venturi tube below the tank with a connection to a stand-pipe in the tank. This action draws oil out of the tank via the standpipe. At the same time, oil is sprayed into the tank in a fine mist, thereby exposing a large amount of oil to the vacuum. When the oil level in the tank falls below the lower of two level switches, a vacuum pump is started, drawing a hard vacuum on the tank through a trap that collects any oil and water entrained in the airflow. When the oil level rises above higher of the two level switches or when the system is shut down, a solenoid valve between the tank and the vacuum pump is closed to prevent suction of oil into the vacuum pump. Critical requirements that the system is designed to satisfy include the following: 1) The circulation pump must have sufficient volume and pressure to operate the venturi tube and spray nozzles. 2) The venturi tube must be sized to empty the tank (except for the oil retained by the standpipe) and maintain a vacuum against the vacuum pump. 3) The tank must be strong enough to withstand atmospheric pressure against the vacuum inside and must have sufficient volume to enable exposure of a sufficiently large amount of sprayed oil to the vacuum. 4) The spray nozzles must be sized to atomize the oil and to ensure that the rate of flow of sprayed oil does not exceed the rate at which the venturi action can empty the tank. 5) The vacuum pump must produce a hard vacuum against the venturi tube and continue to work when it ingests some oil and water. 6) Fittings must be made vacuum tight (by use of O-rings) to prevent leakage of air into the system. The system is fully automatic, and can be allowed to remain in operation with very little monitoring. It is capable of reducing the air content of the oil from 11 to less than 1 volume percent in about 4 hours and to keep the water content below 100 parts per million.

Anderson, Christopher W.

2006-01-01

134

Parameter Designing for Heave Compensation Hydraulic System Installed in Deepwater  

Directory of Open Access Journals (Sweden)

Full Text Available The function diagram of active heave compensation hydraulic system has been given, besides, the mathematics model for the principal hydraulic components of the compensation system has been built, and the input-output relation between components has been made clear. Aimed at compensating work capacity for the system, design and research on parameters as the bearing pressure, the initial state and the maximum flow of hydraulic cylinder, accumulator and other principal components have been made separately, and standardized design has been accomplished in accordance with relevant standards. Furthermore, calculus and verification for the capacity of the hydraulic system in different working stages have been made in order to calculate the pressure lose of the system and provide objective data for the hardware system design of the hydraulic components of the heave compensation system.

Zhao Teng

2013-01-01

135

Analysis of and H? Controller Design For An Electro-Hydraulic Servo Pressure Regulator  

DEFF Research Database (Denmark)

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-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 controller are designed and tested in simulation and experimentally. Finally both controllers are compared to the reference system, finding that similar performance may be obtained, but the used FPGA limits the performance.

Stubkier, SŘren; Pedersen, Henrik C.

2011-01-01

136

Hydraulically actuated hexapod robots design, implementation and control  

CERN Document Server

Legged robots are a promising locomotion system, capable of performing tasks that conventional vehicles cannot. Even more exciting is the fact that this is a rapidly developing field of study for researchers from a variety of disciplines. However, only a few books have been published on the subject of multi-legged robots. The main objective of this book is to describe some of the major control issues concerning walking robots that the authors have faced over the past 10 years. A second objective is to focus especially on very large hydraulically driven hexapod robot locomotion weighing more than 2,000 kg, making this the first specialized book on this topic. The 10 chapters of the book touch on diverse relevant topics such as design aspects, implementation issues, modeling for control, navigation and control, force and impedance control-based walking, fully autonomous walking, walking and working tasks of hexapod robots, and the future of walking robots. The construction machines of the future will very likel...

Nonami, Kenzo; Irawan, Addie; Daud, Mohd Razali

2014-01-01

137

State of the art-hydraulic yaw systems for wind turbines  

DEFF Research Database (Denmark)

This paper addresses the yawing systems of Horizontal Axis Wind Turbines (HAWT’s). HAWT’s represents close to all of the commercial large wind turbines sold today and must be considered state-of-the art within wind turbine technology. Two choices exists when considering components for the active yaw system of a HAWT, electro-mechanical or hydraulic components. In the first generation of larger WT’s hydraulic yaw systems outnumbered the electrical, but in the more recent years there has been a clear shift toward electrical drives, where the yaw drive consist of multiple induction motors each mounted with a reduction gear. This paper presents state-of-the art within; hydraulic yaw system design and control of yaw systems in general. Primary focus on the advantages and disadvantages of using a hydraulic system for controlling the yaw of a wind turbine with a soft yaw concept.

Stubkier, SŘren; Pedersen, Henrik C.

2011-01-01

138

Structure Parameters Optimization Analysis of Hydraulic Hammer System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In order to improve the impact performance, the structure of hydraulic hammer should be optimized. In this paper, the ranges of eight vital structure parameters of piston and reversing valve system of hydraulic hammer were selected firstly; and then found the best value of different parameters under experiments with the method of computer optimization and the parametric analysis method provided by ADAMS software. These methods worked and the best design values of parameters of hydraulic hamme...

Guoping Yang; Jian Fang

2012-01-01

139

Turbogas control unit using a hydraulic interface; Control de una unidad turbogas usando una interfase hidraulica  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the design and implementation of the control system of the Turbo Generator Unit (TGU) GE 5001, placed in Laguna Chavez power generation facility in Gomez Palacio, Dgo., Mexico. This TGU had been operating with an old control system, back to the 70's. The positioning of the control valves was carried out using a complex electro-hydraulic system. For the modernization of the control system, we use latest PLC technology and a current to pressure converter to communicate the PLC with the hydraulic control valves. The new control system helped us to obtain a best response at the start and generation phases, as well as an increase in the availability of the unit. We show the old and the new control architectures besides plot results obtained at the different operation points. [Spanish] En este articulo se presenta la implementacion y diseno del sistema de control de una Unidad Turbogas (UTG) GE-5001 de la Central Turbogas Laguna Chavez de CFE ubicada en Gomez Palacio, Durango, la cual originalmente era controlada mediante un sistema de control con tecnologia de los anos 70's. El posicionamiento de las valvulas de control se realizaba mediante un sistema electro-hidraulico complejo. Para la modernizacion del sistema de control a uno con tecnologia de punta fue necesario utilizar una interfase hidraulica por medio de un convertidor de corriente/presion (I/P) para el posicionamiento de las valvulas originales. Con la modernizacion se mejoro la respuesta del control asi como el incremento de la disponibilidad de la unidad. Se presentan la arquitectura anterior y actual de sistema de control asi como graficas de los resultados obtenidos en diferentes puntos de operacion de la UTG.

Ramirez Palacios, Ignacio Ramon; Castelo Cuevas, Luis [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: irrp@iie.org.mx; lcastelo@iie.org.mx; Escarcega Navarrete, Luis [Servi-Control Monterrey S.A. de C.V., Monterrey, Nuevo Leon (Mexico)]. E-mail: lescarcega@servicontrol.com

2010-11-15

140

Boosted PWM open loop control of hydraulic proportional valves  

International Nuclear Information System (INIS)

This paper presents an innovative open loop control technique for direct single stage hydraulic proportional valves whose response rate is significantly higher than that obtained by standard open loop control techniques, even comparable to more costly commercial closed loop systems. Different from standard open loop techniques, which provide the coil with a constant current proportional to the target position, the control strategy proposed in this paper employs the peak and hold (P and H) technique, widely used in Diesel engine modern supply systems, to boost the duty cycle value of the pulse width modulation (PWM) signal for a short time, namely during the spool displacement, while maintaining a lower duty cycle for holding the spool in the required opening position. The developed 'boosted PWM' technique only requires a low cost microcontroller, such as a peripheral interface controller (PIC) equipped with a metal oxide semiconductor (MOS) power driver. The PWM parameters are calibrated as a function of the spool displacement so as to maximize the response rate without introducing overshoots: the collected data are stored in the PIC. Different valve opening procedures with step response have been compared to demonstrate the merits of the proposed boosted PWM technique. No overshoots have been registered. Moreover, the proposed method is characterized by a significantly higher response rate with respect to a standard open loop control, which approximately has the same cost. Similar experimental tests show that the proposed boosted PWM technique has a response rate even higher than that provided by the more costly commercial closed loop system mounted on the valve, and it produces no overshoots

 
 
 
 
141

Acceptance Test Report for 241-SY Pump Cradle Hydraulic System  

International Nuclear Information System (INIS)

The purpose of this ATP is to verify that hydraulic system/cylinder procured to replace the cable/winch system on the 101-SY Mitigation Pump cradle assembly fulfills its functional requirements for raising and lowering the cradle assembly between 70 and 90 degrees, both with and without pump. A system design review was performed on the 101-SY Cradle Hydraulic System by the vendor before shipping (See WHC-SD-WM-DRR-045, 241-SY-101 Cradle Hydraulic System Design Review). The scope of this plan focuses on verification of the systems ability to rotate the cradle assembly and any load through the required range of motion

142

A dynamical system perspective on plant hydraulic failure  

Science.gov (United States)

is governed by leaf water status that depends on the difference between the rates of transpiration and water supply from the soil and through the plant xylem. When transpiration increases compared to water supply, the leaf water potential reaches a more negative equilibrium, leading to water stress. Both high atmospheric vapor pressure deficit and low soil moisture increase the water demand while decreasing the supply due to lowered soil-to-root conductance and xylem cavitation. Therefore, dry conditions may eventually reduce the leaf water potential to the point of collapsing the plant hydraulic system. This "hydraulic failure" is shown to correspond to a fold bifurcation where the environmental parameters (vapor pressure deficit and soil moisture) trigger the loss of a physiologically sustainable equilibrium. Using a minimal plant hydraulic model, coordination among plant hydraulic traits is shown to result in increased resilience to environmental stresses, thereby impeding hydraulic failure unless hydraulic traits deteriorate due to prolonged water shortage or other damages.

Manzoni, Stefano; Katul, Gabriel; Porporato, Amilcare

2014-06-01

143

Trends in Design of Water Hydraulics : Motion Control and Open-Ended Solutions  

DEFF Research Database (Denmark)

The paper presents and discusses a R&D-view on trends in development and best practise in design of both low-pressure and high-pressure tap water hydraulic components and systems for motion control as well as open-ended solutions various industrial applications. The focus is on the advantages using ordinary tap water and the range of application areas are illustrated with examples, in particular within the food processing industry, humidification operations, water mist systems for fire fighting, high water pressure cleaners, water moisturising systems for wood processing, lumber drying process and mobile machines and equipment that operate in environmentally sensitive surroundings. Today’s progress in water hydraulics includes electro-water hydraulic proportional valves and servovalves for design of motion control solutions for machines and robots. The remarkable property is that the components operate with pure water from the tap without additives of any kind. Hence water hydraulics takes the benefit of purewater as fluid being environmentally friendly, easy to clean sanitary design, non-toxic, non-flammable, inexpensive, readily available and easily disposable. The low-pressure tap water hydraulic systems cover up to around 50 bar, and 2-4 kW having a strong potential to compete with pneumatic and electrical solutions in many applications. The high-pressure water hydraulic systems cover typically up to 160 bar pressure from pump and to motors and actuators 140 bar. Recently, dedicated pumps and accessories running with sea-water as fluid are available. A unique solution is to use reverse osmosis to generate drinking water from sea-water, and furthermore for several off-shore applications. Furthermore, tap water hydraulic components of the Nessie® family and examples of measured performance characteristics are presented and the trends in industrial applications and need for future are discussed.

Conrad, Finn Technical University of Denmark,

2005-01-01

144

49 CFR 570.57 - Air brake system and air-over-hydraulic brake subsystem.  

Science.gov (United States)

...2010-10-01 false Air brake system and air-over-hydraulic brake subsystem. 570...570.57 Air brake system and air-over-hydraulic brake subsystem. ...brake and air-over-hydraulic brake systems. Trailer(s)...

2010-10-01

145

Hydraulic control rod drive for water-cooled nuclear reactors, particularly heating reactors  

International Nuclear Information System (INIS)

This invention consists of a hydraulic control rod drive for water-cooled nuclear reactors, particularly heating reactors, having a reactor pressure vessel and having a reactor core supported in it, consisting of a fuel assembly field in an upright configuration and control rods supported so that they can be inserted into or withdrawn from interspaces between the fuel assemblies, in or counter to the direction of gravity, whereby drive rods of the control rods are provided with hydraulic piston-cylinder systems, to which the cooling water can be supplied from below as the working fluid through reactor-internal fluid lines, whereby the cooling water reservoir is used as a hydraulic drain. 13 figs

146

46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.  

Science.gov (United States)

...2010-10-01 2010-10-01 false Hydraulic or pneumatic power and control-materials...Materials and Pressure Design § 128.240 Hydraulic or pneumatic power and control—materials...flanges, and standard valves) for hydraulic or pneumatic power and control...

2010-10-01

147

Structure Parameters Optimization Analysis of Hydraulic Hammer System  

Directory of Open Access Journals (Sweden)

Full Text Available In order to improve the impact performance, the structure of hydraulic hammer should be optimized. In this paper, the ranges of eight vital structure parameters of piston and reversing valve system of hydraulic hammer were selected firstly; and then found the best value of different parameters under experiments with the method of computer optimization and the parametric analysis method provided by ADAMS software. These methods worked and the best design values of parameters of hydraulic hammer were obtained. At last, the optimal impact energy of virtual prototype of hydraulic breaking hammer was calculated and compared with the original impact performance. The results reveal that impact performance of hydraulic hammer has been improved significantly.

Guoping Yang

2012-11-01

148

Energy efficient control of working hydraulics; Energieeffiziente Ansteuerung der Arbeitshydraulik  

Energy Technology Data Exchange (ETDEWEB)

Challenges such as declining fuel resources and global warming are forcing manufacturers of mobile working machines to increase the energy efficiency of their products. Within the framework of the project Steam, the Institute for Fluid Power Drives and Controls (IFAS) at RWTH Aachen University are currently validating a holistic design approach aimed at improving the efficiency of both the internal combustion engine and the working hydraulics. (orig.)

Sgro, Sebastian; Vukovic, Milos; Murrenhoff, Hubertus [RWTH Aachen Univ. (Germany). Inst. fuer Fluidtechnische Antriebe und Steuerungen (IFAS)

2013-10-15

149

Output Feedback Control of Electro-Hydraulic Cylinder Drives using the Twisting Algorithm  

DEFF Research Database (Denmark)

This paper discusses the utilization of the so-called twisting algorithm when applied in output feedback position control schemes for electro-hydraulic cylinder drives. The twisting controller was the first second order sliding controller ever introduced, and can structure-wise be considered a straight forward extension of the simplest first order sliding controller, that is, a relay controller. Such a controller may be implemented without the knowledge of system time constants etc., as opposed to the surface based first order sliding controllers which has been presented in numerous contributions in literature. This paper considers the twisting algorithm when applied directly for output feedback control, and with the design based on a reduced order model representation of an arbitrary valve driven hydraulic cylinder drive. The consequence of implementing such a controller with the well-known saturation-, or boundary layer method is discussed, and the control operation inside- and outside the boundary layer region is considered. Furthermore, the global stability of such a controller is discussed, with emphasis on possible local instability modes. Results demonstrate that the proposed output feedback controller may be successfully applied to hydraulic valve driven cylinder drives, with performance being on the level with a conventional surface based first order sliding mode controller.

Schmidt, Lasse; Andersen, Torben Ole

2014-01-01

150

Capsule injection system for a hydraulic capsule pipelining system  

Science.gov (United States)

An injection system for injecting capsules into a hydraulic capsule pipelining system, the pipelining system comprising a pipeline adapted for flow of a carrier liquid therethrough, and capsules adapted to be transported through the pipeline by the carrier liquid flowing through the pipeline. The injection system comprises a reservoir of carrier liquid, the pipeline extending within the reservoir and extending downstream out of the reservoir, and a magazine in the reservoir for holding capsules in a series, one above another, for injection into the pipeline in the reservoir. The magazine has a lower end in communication with the pipeline in the reservoir for delivery of capsules from the magazine into the pipeline.

Liu, Henry (Columbia, MO)

1982-01-01

151

Design of a Hydraulic Motor System Driven by Compressed Air  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents the design of a highly efficient pneumatic motor system. The air engine is currently the most generally used device to convert potential energy of compressed air into mechanical energy. However, the efficiency of the air engines is too low to provide sufficient operating range for the vehicle. In this study, the energy contained in compressed air/pressurized hydraulic oil is transformed by a hydraulic motor to mechanical energy to enhance the efficiency of using air power. To evaluate the theoretical efficiency, the principle of balance of energy is applied. The theoretical efficiency of converting air into hydraulic energy is found to be a function of pressure; thus, the maximum converting efficiency can be determined. To confirm the theoretical evaluation, a prototype of the pneumatic hydraulic system is built. The experiment verifies that the theoretical evaluation of the system efficiency is reasonable, and that the layout of the system is determined by the results of theoretical evaluation.

Jyun-Jhe Yu

2013-06-01

152

Combustion waves in hydraulically resisted systems.  

Science.gov (United States)

The effects of hydraulic resistance on the burning of confined/obstacle-laden gaseous and gas-permeable solid explosives are discussed on the basis of recent research. Hydraulic resistance is found to induce a new powerful mechanism for the reaction spread (diffusion of pressure) allowing for both fast subsonic as well as supersonic propagation. Hydraulic resistance appears to be of relevance also for the multiplicity of detonation regimes as well as for the transitions from slow conductive to fast convective, choked or detonative burning. A quasi-one-dimensional Fanno-type model for premixed gas combustion in an obstructed channel open at the ignition end is discussed. It is shown that, similar to the closed-end case studied earlier, the hydraulic resistance causes a gradual precompression and preheating of the unburned gas adjacent to the advancing deflagration, which leads (after an extended induction period) to a localized autoignition that triggers an abrupt transition from deflagrative to detonative combustion. In line with the experimental observations, the ignition at the open end greatly encumbers the transition (compared with the closed-end case), and the deflagration practically does not accelerate up to the very transition point. Shchelkin's effect, that ignition at a small distance from the closed end of a tube facilitates the transition, is described. PMID:22213662

Brailovsky, I; Kagan, L; Sivashinsky, G

2012-02-13

153

Study on step-down dynamic process of hydraulic cylinder for control rod hydraulic drive mechanism  

International Nuclear Information System (INIS)

Hydraulic cylinder (HC) is the key component of the control rod hydraulic drive mechanism(CRHDM). According to the characteristics of HC step-down process,the pressure transients in the HC during step-down process can be divided into two processes, that is, the pressure transients before step-down motion and the pressure transients during step-down motion. Theoretical dynamic pressure models of these two processes were built. And among them,the theoretical dynamic pressure model during HC step-down motion can be combined with the HC step-down kinematics model to establish a complete HC step-down dynamic model. The comparison between the theoretical results and the CRHDM single cylinder experiment shows that,under the experimental loadings, the theoretical dynamic pressure transients during the HC step-down process and the HC step-down displacements agree with the experimental results. The research results have laid the theoretical foundation for the acquisition of the key factors affecting the pressure transients of the HC during step-down process and the step motion time of the CRHDM. (authors)

154

A 6-DOF vibration isolation system for hydraulic hybrid vehicles  

Science.gov (United States)

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 the regenerative system.

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

2006-03-01

155

A Model Predictive Control Approach for Fuel Economy Improvement of a Series Hydraulic Hybrid Vehicle  

Directory of Open Access Journals (Sweden)

Full Text Available This study applied a model predictive control (MPC framework to solve the cruising control problem of a series hydraulic hybrid vehicle (SHHV. The controller not only regulates vehicle velocity, but also engine torque, engine speed, and accumulator pressure to their corresponding reference values. At each time step, a quadratic programming problem is solved within a predictive horizon to obtain the optimal control inputs. The objective is to minimize the output error. This approach ensures that the components operate at high efficiency thereby improving the total efficiency of the system. The proposed SHHV control system was evaluated under urban and highway driving conditions. By handling constraints and input-output interactions, the MPC-based control system ensures that the system operates safely and efficiently. The fuel economy of the proposed control scheme shows a noticeable improvement in comparison with the PID-based system, in which three Proportional-Integral-Derivative (PID controllers are used for cruising control.

Tri-Vien Vu

2014-10-01

156

State of Art of the CAREM-25 Hydraulic Control Rod Drives Feasibility Analysis  

International Nuclear Information System (INIS)

The proposed design adopted for the control rod drives for the CAREM reactor is based on a hydraulic system.As any innovative device, the design process requires to obtain experimental evidence to identify the most important control parameters and to set their relationship with other design parameters, in order to guarantee its feasibility as a previous step to the design qualification tests at the working conditions at the reactor.This paper features a global evaluation of the analysis performed and experimental results obtained in a low pressure loop, design improvements, limiting phenomena identified and corrective actions analyzed or proposed.The evaluation is based on a repetitivity, sensitivity and scalability study of the control parameters and test conditions, as well as the dynamic response between rod drive and the hydraulic system and features related with the mechanical design.Obtained results show that present system has an adequate response compatible with functional and manufacturing requirements

157

Contaminant monitoring of hydraulic systems. The need for reliable data  

Energy Technology Data Exchange (ETDEWEB)

The need for both reliable operation of hydraulic and lubrication systems and long component lives has focused users to the benefits of controlling the contamination in the hydraulic fluid. Maximum operating (target) levels are being implemented as part of a condition based maintenance regime. If these are exceeded, maintenance effort is directed to correcting the rise in consummation level, and so make optimum use of resources as maintenance effort is only affected when it is necessary to do so. Fundamental to ibis aspect of condition based monitoring is the provision of accurate and reliable data in the shortest possible time. This way, corrective actions can be implemented immediately so minimising the damage to components. On-line monitoring devices are a way of achieving this and are seeing increased use, but some are affected by the condition of the fluid. Hence, there is a potential for giving incorrect data which will waste time and effort by initiating unnecessary corrective actions. A more disturbing aspect is the effect on the user of continual errors. The most likely effect would be a loss of confidence in the technique or even complete rejection of it and hence the potential benefits will be lost. This presentation explains how contaminant monitoring techniques are applied to ensure that the potential benefits of operating with clean fluids is realised. It examines the sources of error and shows how the user can interrogate the data and satisfy himself of its authenticity. (orig.) 14 refs.

Day, M.J. [Pall Europe Ltd., Portsmouth (United Kingdom)] Rinkinen, J. [Tampere University of Technology, Tampere (Finland)

1997-12-31

158

A Frequency Response Approach to Sliding Control Design for Hydraulic Drives  

DEFF Research Database (Denmark)

Sliding modes applied in control structures may generally provide for perfect control performance and robustness toward uncertain bounded parameters and disturbances, in the ideal case with infinite actuator bandwidth and switching frequency. However, in the context of physical systems, such performance cannot be realized due to finite actuator bandwidths and switching frequencies, which, in the case of direct application of sliding control terms, may lead to control chattering and high frequency oscillations in the system states. In order to compensate for this undesirable effect, the application of so-called boundary layers are commonly applied, guaranteeing sliding precision in some well-defined vicinity of the control target. Commonly the control target, or sliding manifold, is designed as some desired closed loop dynamics of the controlled plant, utilizing multiple states as feedback. However, when considering hydraulic cylinder drives, such full state feedback may not be available, and alternative approaches to conventional methods may be considered. This issue is addressed in this paper in regard to tracking control design for valve controlled hydraulic cylinder drives, and a design method taking its offset in linear analysis is proposed. The sliding manifold is designed based on a PI controller design, and the resulting controller provides for robustness outside a predefined boundary layer, and performance equivalent to the PI controller within the boundary layer. Results demonstrate improved tracking accuracy of the proposed controller compared the PI controller, and that performance of these controllers is equivalent within the boundary layer.

Schmidt, Lasse; Johansen, Per

2014-01-01

159

Kinetic resistance of hydraulic cylinder for control rod hydraulic drive mechanism in step-down motion process  

International Nuclear Information System (INIS)

Hydraulic cylinder is the main component of the control rod hydraulic drive mechanism (CRHDM). Step-up and step-down motions are the functions of hydraulic cylinder. The kinetic resistance of hydraulic cylinder during step-down motion is the key parameter in the hydraulic cylinder structure design and step-down analysis. Theoretical analysis of hydraulic cylinder step-down process was carried out to establish the dynamic model of the process. The step-down velocity and acceleration were obtained by combining the step-down dynamic model and the results of the CRHDM single cylinder experiment, which lead to two sets of step-down kinetic resistance models. Comparison of these two models and their calculation results shows that, under the experimental conditions, the displacement curves inferred from these models agree with the experimental data. And in the model based on step-down acceleration the kinetic resistance is the function of inner cylinder's velocity and the hydraulic pressure inside the cylinder, the relationship of the coefficients in the model to the loadings is easy to obtain, so the kinetic resistance model based on step-down acceleration is more applicable to engineering use and extension. (authors)

160

Hydraulic external pre-isolator system for LIGO  

Science.gov (United States)

The hydraulic external pre-isolator (HEPI) is the first six degrees of freedom active seismic isolation system implemented at the Laser Interferometer Gravitational Wave Observatory (LIGO). Implementation was first completed at the LIGO Livingston Observatory (LLO) prior to LIGO's fifth science run7, successfully cutting down the disturbance seen by LLO's suspended optics in the two most prominent seismic disturbance bands, the microseism (0.1–0.3 Hz) and the anthropogenic (1–3 Hz) bands, by a factor of a few to tens. The improvement in seismic isolation contributed directly to LLO's much improved duty cycle of 66.7% and LIGO's triple coincident duty cycle of 53%. We report the design, control scheme, and isolation performance of HEPI at LLO in this paper. Aided by this success, funding for incorporating HEPI into the LIGO Hanford Observatory was approved and installation is currently underway.

Wen, S.; Mittleman, R.; Mason, K.; Giaime, J.; Abbott, R.; Kern, J.; O'Reilly, B.; Bork, R.; Hammond, M.; Hardham, C.; Lantz, B.; Hua, W.; Coyne, D.; Traylor, G.; Overmier, H.; Evans, T.; Hanson, J.; Spjeld, O.; Macinnis, M.; Mailand, K.; Ottaway, D.; Sellers, D.; Carter, K.; Sarin, P.

2014-12-01

 
 
 
 
161

Hydraulic External Pre-Isolator System for LIGO  

CERN Document Server

The Hydraulic External Pre-Isolator (HEPI) is the first 6 degrees of freedom active seismic isolation system implemented at the Laser Interferometer Gravitational Wave Observatory (LIGO). Implementation was first completed at the LIGO Livingston Observatory (LLO) prior to LIGO's 5th science run, successfully cutting down the disturbance seen by LLO's suspended optics in the two most prominent seismic disturbance bands, the microseism (0.1-0.3Hz) and the anthropogenic (1-3Hz) bands, by a factor of a few to tens. The improvement in seismic isolation contributed directly to LLO's much improved duty cycle of 66.7% and LIGO's triple coincident duty cycle of 53%. We report the design, control scheme, and isolation performance of HEPI at LLO in this paper. Aided with this success, funding for incorporating HEPI into the LIGO Hanford Observatory was approved and installation is currently underway.

Wen, S; Mason, K; Giaime, J; Abbott, R; Kern, J; O'Reilly, B; Bork, R; Hammond, M; Hardham, C; Lantz, B; Hua, W; Coyne, D; Traylor, G; Overmier, H; Evans, T; Hanson, J; Spjeld, O; Macinnis, M; Mailand, K; Sellers, D; Carter, K; Sarin, P

2013-01-01

162

Evidence for internal hydraulic control in the northern Řresund  

DEFF Research Database (Denmark)

New observations of mainly flow velocity, salinity, and temperature are used to show and discuss some of the physical conditions in Oslashresund, the strait between Denmark and Sweden, one of three connections between the brackish Baltic Sea and the saline North Sea. The main geometric features are a contraction in the northern Oslashresund and the shallow Drogden sill at the entrance to the Baltic. The observations show that the two-layer flows through the contraction are often hydraulically controlled. The observations also reveal details of the transition from subcritical to supercritical flow. In terms of the composite Froude number, on the basis of local flow parameters these details are that the flow may be subcritical as well as supercritical in different areas of some cross section. Existing theories on rotating hydraulics are unable to account for these circumstances, which are due to the strong influence of the Earth's rotation and the curvature of the streamlines. In the present study it is not attempted to explain these conditions, but the probable effects of rotation and curvature on the controlled flow rate are discussed briefly. Also, the possible effects of hydraulic control on the exchange of the Baltic are discussed. It is argued that the stratification in the Kattegat, the sea to the north, is more important than the presence of the Drogden sill for the amount of high saline water to enter the Baltic through Oslashresund. This result is supported by observations of the stratification in Oslashresund and the flow at the sill. The observations show that the interface in Oslashresund rises significantly during flow to the Baltic and that the transport of saline water into the Baltic is closely connected to the shallowness of the interface in Oslashresund

Nielsen, Morten Holtegaard

2001-01-01

163

Application of multi-sensor information fusion technology on fault diagnosis of hydraulic system  

International Nuclear Information System (INIS)

The structural layers and methods of multi-sensor information fusion technology are analysed, and its application in fault diagnosis of hydraulic system is discussed. Aiming at hydraulic system, a model of hydraulic fault diagnosis system based on multi-sensor information fusion technology is presented. Choosing and implementing the method of information fusion reasonably, the model can fuse and calculate various fault characteristic parameters in hydraulic system effectively and provide more valuable result for fault diagnosis of hydraulic system.

164

A new approach for failure prediction in mobile hydraulic systems  

Energy Technology Data Exchange (ETDEWEB)

In this work a new approach to set up a condition monitoring (CM) system for mobile hydraulic systems is investigated. This approach focuses on an early detection and allocation of impending failures without modelling the hydraulic system and using a minimum amount on additional sensor information. In a first step critical components of mobile hydraulic systems are specified that may be worthy for diagnostics. Based on a demonstrator machine, a wheel loader, critical sub modules are brought out and possible applicable CM-methods are specified and selected. Two basic methods - the thermodynamic and the structure borne noise method - are investigated and combined. The new CM-approach is experimentally investigated on two different laboratory test rigs by implementing a large number of different artificial faults. The laboratory tests are also used to determine the minimum requirements on system information. Finally the proposed methods are implemented on a mobile off-road vehicle and tested under different operational conditions in-field. (orig.)

Oppermann, M.

2007-07-01

165

Primary system thermal hydraulics of future FBRS  

International Nuclear Information System (INIS)

As a follow-up to PFBR (Indian Prototype Fast Breeder Reactor), many FBRs of 500 MWe capacity are planned. The focus of these future FBRs is improved economy and enhanced safety. They are envisaged to have a twin-unit concept. Design and construction experiences gained from PFBR project have motivated the centre to achieve an optimized design for future FBRs with significant design changes for many critical components. Some of the design changes include, (i) provision of four primary pipes per primary sodium pump, (ii) inner vessel with single torus lower part, (iii) Roof Slab (RS) with a dome shape supported on Reactor Vault (RV), (iv) machined thick plate rotating plugs, (v) reduced main vessel diameter with narrow-gap cooling baffles and (vi) safety vessel integrated with RV. This paper covers thermal hydraulic design validation of the chosen options with respect to hot and cold pool thermal hydraulics, flow requirement for main vessel cooling, inner vessel temperature distribution, safety analysis of primary pipe rupture event, cold pool transient thermal loads and thermal management of top shield and reactor vault. (author)

166

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

Energy Technology Data Exchange (ETDEWEB)

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

1988-01-01

167

Teaching Thermal Hydraulics & Numerical Methods: An Introductory Control Volume Primer  

Energy Technology Data Exchange (ETDEWEB)

A graduate level course for Thermal Hydraulics (T/H) was taught through Idaho State University in the spring of 2004. A numerical approach was taken for the content of this course since the students were employed at the Idaho National Laboratory and had been users of T/H codes. The majority of the students had expressed an interest in learning about the Courant Limit, mass error, semi-implicit and implicit numerical integration schemes in the context of a computer code. Since no introductory text was found the author developed notes taught from his own research and courses taught for Westinghouse on the subject. The course started with a primer on control volume methods and the construction of a Homogeneous Equilibrium Model (HEM) (T/H) code. The primer was valuable for giving the students the basics behind such codes and their evolution to more complex codes for Thermal Hydraulics and Computational Fluid Dynamics (CFD). The course covered additional material including the Finite Element Method and non-equilibrium (T/H). The control volume primer and the construction of a three-equation (mass, momentum and energy) HEM code are the subject of this paper . The Fortran version of the code covered in this paper is elementary compared to its descendants. The steam tables used are less accurate than the available commercial version written in C Coupled to a Graphical User Interface (GUI). The Fortran version and input files can be downloaded at www.microfusionlab.com.

D. S. Lucas

2004-10-01

168

A Novel Control Approach Based on Second Order Sliding Modes & Its Application to Hydraulic Drives  

DEFF Research Database (Denmark)

Sliding modes impose strong robustness toward parametric plant uncertainties and disturbances and accurate tracking performance in control systems. However, in physical systems the application of sliding modes may give rise to undesirable chattering of the control signal due to actuator dynamics. This may be avoided by application of smoothing functions imposing boundary layers on the control constraint, or by carrying out the design in relation to the control derivative. However, such boundary layers introduces additional design parameters and actuator dynamics may not allow the desired control accuracy to be reached. In this paper a novel control approach based on second order sliding modes utilizing the idea of the power rate reaching law is introduced. Dependent on parameters the proposed controller may preserve the main features of sliding controls, while at the same time avoiding control chattering. Simulation studies confirm the announced properties when applied to a hydraulic drive model subjected to strong variations in supply pressure and friction.

Schmidt, Lasse; Andersen, Torben Ole

2013-01-01

169

Accumulator isolator prevents malfunctioning of faulty hydraulic system  

Science.gov (United States)

Special isolator valve prevents malfunction of a closed hydraulic system by converting the initial accumulator-reservoir to a reservoir function only when the system loses oil, or gaseous nitrogen precharge, or has a jammed piston. This permits near-normal operation until the defect is corrected.

Walsh, G. D.

1967-01-01

170

Fluid shear influences on the performance of hydraulic flocculation systems.  

Science.gov (United States)

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

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

2011-11-01

171

Understanding the Space Shuttle Main Engine Hydraulic Actuation System and Reviewing Its Evolution  

Science.gov (United States)

The complex engine start and thrust control requirements of the Space Shuttle Main Engine (SSME) require unique valve, actuator and control system hardware. The Hydraulic Actuation System (HAS) was designed, developed, and now operates to meet tight engine control requirement limits to assure safe, reliable and correct engine thrust at all times. The actuator is designed to be fail safe and fail operate in the areas where redundancy is important. The HAS has an additional pneumatic operating capability that insures a safe sequential closure of all actuators and propellant valves in the event of the loss of hydraulic system pressure or loss of electrical closed loop control of the actuator. The objective of this paper is to provide a complete description of the actuator s internal operating system, along with its interaction with all SSME system interfaces. Additionally the paper addresses the challenges, problems identified, and corrected, and lessons learned, during the course of the almost 35 years of engine operation.

McWade, Robert J.; Minor, Robert B.; McNutt, Leslie M.

2010-01-01

172

Test Rig Design and Presentation for a Hydraulic Yaw System  

DEFF Research Database (Denmark)

The design and development of a hydraulic yaw system for multi MWturbines is presented and the concept explained. As part of the development of the new concept a full scale test rig for a 5 MW wind turbine has been designed and constructed. The test rig is presented along with its unique design features. The design process is outlined to give insight in the design criteria driving the design. Loads and yaw demands are based on the IEC 61400-1 standard for wind turbine design, and the loads for this examination are extrapolated from the FAST aero elastic design software. The concepts are based on a 5 MW offshore turbine. After the system presentation, measurement results are presented to verify the behavior of the system. The loads to the system are applied by torque controlled electrical servo drives, which can add a load of up to 3 MNm to the system. This gives an exact picture of the system dynamics under real conditions. The behavior of the system is analyzed with regard to 20 years of operation. This is for example done by applying loads from different design load cases, e.g. normal turbulence, extreme turbulence and different fault scenarios on the turbine. The paper first presents an introduction with the current state of the art and problem description, followed by a system description, where the system is designed and dimensioned. Based on the design, results from the test rig are presented and analyzed. Finally a conclusion summing up the design, model and test results is given.

Stubkier, SŘren; Pedersen, Henrik C.

2013-01-01

173

Aircraft Hydraulic System Dynamic Analysis. Volume III. Frequency Response (HSFR) Computer Program User Manual.  

Science.gov (United States)

The hydraulic system frequency response (HSFR) computer program was developed to simulate the dynamic response of a hydraulic system to the acoustic noise generated by the pump. Detailed instructions for modeling the system pump, lines, and components, an...

G. Amies, B. Greene

1977-01-01

174

Recurrent-neural-network-based identification of a cascade hydraulic actuator for closed-loop automotive power transmission control  

International Nuclear Information System (INIS)

By virtue of its ease of operation compared with its conventional manual counterpart, automatic transmissions are commonly used as automotive power transmission control system in today's passenger cars. In accordance with this trend, research efforts on closed-loop automatic transmission controls have been extensively carried out to improve ride quality and fuel economy. State-of-the-art power transmission control algorithms may have limitations in performance because they rely on the steady-state characteristics of the hydraulic actuator rather than fully exploit its dynamic characteristics. Since the ultimate viability of closed-loop power transmission control is dominated by precise pressure control at the level of hydraulic actuator, closed-loop control can potentially attain superior efficacy in case the hydraulic actuator can be easily incorporated into model-based observer/controller design. In this paper, we propose to use a recurrent neural network (RNN) to establish a nonlinear empirical model of a cascade hydraulic actuator in a passenger car automatic transmission, which has potential to be easily incorporated in designing observers and controllers. Experimental analysis is performed to grasp key system characteristics, based on which a nonlinear system identification procedure is carried out. Extensive experimental validation of the established model suggests that it has superb one-step-ahead prediction capability over appropriate frequency range, making it an attractive approach for model-based observer/controller design applications in automotive systems

175

Mathematical modelling of hydraulic conditions of balancing and control of heating, cooling and dehumidification subsystem in ventilation and air conditioning systems  

Directory of Open Access Journals (Sweden)

Full Text Available The goal of these investigations is modeling of processes and studying of influence of quantitative characteristics and parameters in heating and cooling subsystem of ventilation and air conditioning systems at balancing this subsystem by means of various balancing valves and control of three-running valve. Balancing and management processes are considered on an example of the binding water air-heater of ventilation and air conditioning system. Besides, influence of various regime parameters on considered balancing characteristics is studied, as that: difference of pressure in a network of a heat supply, the pressure created by the pump, their parity, various water temperatures, the modes leading to self-oscillations. Result of work is reception of balancing and adjusting characteristics of a considered subsystem in most general view under various working conditions and their further analysis.

A.P. Rusakov

2011-01-01

176

The hydraulic lifting system for the main magnets of CYCIAE-30 cyclotron  

CERN Document Server

The oil-line structure, control system and their working principles of the hydraulic lifting system for the main magnets of CYCIAE-30 cyclotron are introduced. The six years practice proves that the specification of the system matches the requirements: the oil cylinder maximum stroke of 850 mm, the eight slot positioning dowels repositioning accuracy of +-0.01 mm, the two oil cylinders moving in step accuracy of 5-10 mm. The system is safe, reliable and easy to be operated

Zhao Zhen Lu; Chen Rong Fan; Chu Cheng Jie

2002-01-01

177

The hydraulic lifting system for the main magnets of CYCIAE-30 cyclotron  

International Nuclear Information System (INIS)

The oil-line structure, control system and their working principles of the hydraulic lifting system for the main magnets of CYCIAE-30 cyclotron are introduced. The six years practice proves that the specification of the system matches the requirements: the oil cylinder maximum stroke of 850 mm, the eight slot positioning dowels repositioning accuracy of +-0.01 mm, the two oil cylinders moving in step accuracy of 5-10 mm. The system is safe, reliable and easy to be operated

178

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

Directory of Open Access Journals (Sweden)

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.

Teodor Eugen Man

2010-01-01

179

Research on MEMS sensor in hydraulic system flow detection  

Science.gov (United States)

With the development of mechatronics technology and fault diagnosis theory, people regard flow information much more than before. Cheap, fast and accurate flow sensors are urgently needed by hydraulic industry. So MEMS sensor, which is small, low cost, well performed and easy to integrate, will surely play an important role in this field. Based on the new method of flow measurement which was put forward by our research group, this paper completed the measurement of flow rate in hydraulic system by setting up the mathematical model, using numerical simulation method and doing physical experiment. Based on viscous fluid flow equations we deduced differential pressure-velocity model of this new sensor and did optimization on parameters. Then, we designed and manufactured the throttle and studied the velocity and pressure field inside the sensor by FLUENT. Also in simulation we get the differential pressure-velocity curve .The model machine was simulated too to direct experiment. In the static experiments we calibrated the MEMS sensing element and built some sample sensors. Then in a hydraulic testing system we compared the sensor signal with a turbine meter. It presented good linearity and could meet general hydraulic system use. Based on the CFD curves, we analyzed the error reasons and made some suggestion to improve. In the dynamic test, we confirmed this sensor can realize high frequency flow detection by a 7 piston-pump.

Zhang, Hongpeng; Zhang, Yindong; Liu, Dong; Ji, Yulong; Jiang, Jihai; Sun, Yuqing

2011-05-01

180

The 25 kWe solar thermal Stirling hydraulic engine system: Conceptual design  

Science.gov (United States)

The conceptual design and analysis of a solar thermal free-piston Stirling hydraulic engine system designed to deliver 25 kWe when coupled to a 11 meter test bed concentrator is documented. A manufacturing cost assessment for 10,000 units per year was made. The design meets all program objectives including a 60,000 hr design life, dynamic balancing, fully automated control, more than 33.3 percent overall system efficiency, properly conditioned power, maximum utilization of annualized insolation, and projected production costs. The system incorporates a simple, rugged, reliable pool boiler reflux heat pipe to transfer heat from the solar receiver to the Stirling engine. The free-piston engine produces high pressure hydraulic flow which powers a commercial hydraulic motor that, in turn, drives a commercial rotary induction generator. The Stirling hydraulic engine uses hermetic bellows seals to separate helium working gas from hydraulic fluid which provides hydrodynamic lubrication to all moving parts. Maximum utilization of highly refined, field proven commercial components for electric power generation minimizes development cost and risk.

White, Maurice; Emigh, Grant; Noble, Jack; Riggle, Peter; Sorenson, Torvald

1988-01-01

 
 
 
 
181

Aircraft Hydraulic System Dynamic Analysis. Volume IV. Frequency Response (HSFR) Computer Program Technical Description.  

Science.gov (United States)

The hydraulic system frequency response (HSFR) computer program was developed to simulate the dynamic response of a hydraulic system to the acoustic noise generated by the pump. A detailed technical description of the program is presented. For a selected ...

G. Amies, B. Greene

1977-01-01

182

Aircraft hydraulic power system diagnostic, prognostics and health management  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This Individual Research Project (IRP) is the extension research to the group design project (GDP) work which the author has participated in his Msc programme. The GDP objective is to complete the conceptual design of a 200-seat, flying wing civil airliner—FW-11. The next generation aircraft design demands higher reliability, safety and maintainability. With the development of the vehicle hydraulic system technology, the equipment and systems become more and more complex, their reliabili...

Wang, Jian

2012-01-01

183

14 CFR 25.1435 - Hydraulic systems.  

Science.gov (United States)

...simultaneously; (4) Withstand the fatigue effects of all cyclic pressures...station to indicate appropriate system parameters, if (i) It performs a function...must be subjected to performance, fatigue, and endurance tests...

2010-01-01

184

The Integration of an Electro-Hydraulic Manipulator Arm into a Self-Contained Mobile Delivery System  

Energy Technology Data Exchange (ETDEWEB)

The Portable Articulated Arm Deployment System (PAADS) is a remotely controlled vehicle for delivering a tele-operated electro-hydraulic manipulator arm to a field-deployable location. The self-contained system includes a boom vehicle with long reach capability, an electro-hydraulic manipulator arm, closed circuit television (CCTV) systems, and onboard tools. On board power systems consist of a self-contained, propane-fired 8-KW generator and an air compressor for pneumatic tools. The generator provides the power to run the air compressor as well as power to operate the 110-VAC auxiliary lighting system for the video cameras. The separate control console can be located up to 500 ft from the vehicle. PAADS is a fully integrated system, containing all equipment required to perform complex field operations. Hydraulic integration of the manipulator arm into the vehicle hydraulic drive system was necessary to eliminate the tether management of hoses, which extended vehicle operating range, minimized hydraulic pressure losses, and provided the opportunity to go to a radio frequency (RF) control system in the future, thereby eliminating the control cable. This paper presents the key decision points during system development. Emphasis is placed on ease of operator control and not on an intelligent machine approach. In addition, emphasis is placed on the philosophy of remote operation based on sound principles of integration.

M. Borland; S. M. Berry

1999-04-01

185

The Integration of an Electro-hydraulic Manipulator Arm into a Self-contained Mobile Delivery System  

Energy Technology Data Exchange (ETDEWEB)

The Portable Articulated Arm Deployment System (PAADS) is a remotely controlled vehicle for delivering a tele-operated electro-hydraulic manipulator arm to a field deployable location. The self-contained system includes a boom vehicle with long reach capability, an electro-hydraulic manipulator arm, closed circuit television (CCTV) systems, and onboard tools. On board power systems consist of a self contained, propane fired 8 KW generator and an air compressor for pneumatic tools. The generator provides the power to run the air compressor as well as provide power to operate the 110 VAC auxiliary lighting system for the video cameras. The separate control console can be located up to 500 ft from the vehicle. PAADS is a fully integrated system, containing all equipment required to perform complex field operations. Hydraulic integration of the manipulator arm into the vehicle hydraulic drive system was necessary to eliminate the tether management of hoses, which extended vehicle operating range, minimized hydraulic pressure losses, and provided the opportunity to go to a radio frequency (RF) control system in the future, thereby eliminating the control cable. This paper presents the key decision points during system development. Emphasis is placed on ease of operator control and not on an intelligent machine approach. In addition, emphasis is placed on the philosophy of remote operation based on sound principles on integration.

Borland, Mark Wilson; Berry, Stephen Michael

1999-04-01

186

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

DEFF Research Database (Denmark)

This paper presents a new hydraulic yaw system for wind turbines. The basic component is a new type of hydraulic motor characterized by an extraordinary high specific displacement yielding high output torque in a compact form. The focus in the paper is the volumetric efficiency of the motor, which is based on leakage flow. The most critical gaps in the motor, across the end faces of the rotor, are investigated both by a fluid structural interaction simulation model and by experimental prototype tests. The simulation model is the basis for the motor design and the manufacturing tolerances. The volumetric efficiency is highly dependent on the structural deflections caused by the pressure distribution in the fluid films across the rotor. This gap height is measured with a 0.1?m resolution "SMAC Moving Coil Actuator" in the experimental test setup. When the pressure in the pressure compensation volumes is minimizing the deflections, the measured gap height is around ? = 10?m and the volumetric efficiency of the motor is around ?v = 0.85. By decreasing the initial gaps from the manufacturing process, this volumetric efficiency can be further increased.

SŘrensen, Rasmus MŘrk; Hansen, Michael Rygaard

2011-01-01

187

Mathematical modelling of hydraulic conditions of balancing and control of heating, cooling and dehumidification subsystem in ventilation and air conditioning systems  

Directory of Open Access Journals (Sweden)

Full Text Available The article is the second part of the one published in the Vol. 1, 2011. The aim of this research is processes modelling and investigation of quantity parameters influence on heating and cooling subsystem of VAC systems when balancing that subsystem by various balanced valves and when controlling it by three-way valve. The basic characteristic received and analyzed in model, is balancing-adjusting characteristic (schedule of mixture in knot depending on a combination of many factors: binding, crosspieces, an arrangement of corresponding valves, pressures and other parameters. For reception of the balancing-adjusting characteristic of subsystem in different operating modes its mathematical model was created, methods of processing and generalization of the data were offered. After that calculations in different modes of use of the crosspieces were done, allowed to define all regime parameters at the set positions of balancing and regulating valves, parity of pressures in a network and a pump, design of armature and entry conditions.

A. G. Sotnikov

2011-03-01

188

14 CFR 29.1435 - Hydraulic systems.  

Science.gov (United States)

...and supported to prevent excessive vibration and to withstand inertia loads. Each element of the installation must be protected from...element of the system must be tested to a proof pressure of 1.5 times the maximum pressure to which that element will be...

2010-01-01

189

Engine having a high pressure hydraulic system and low pressure lubricating system  

Science.gov (United States)

An engine includes a high pressure hydraulic system having a high pressure pump and at least one hydraulically-actuated device attached to an engine housing. A low pressure engine lubricating system is attached to the engine housing and includes a circulation conduit fluidly connected to an outlet from the high pressure pump.

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

2000-01-01

190

THERMAL HYDRAULIC ANALYSIS OF A GAS TEST LOOP SYSTEM  

International Nuclear Information System (INIS)

This paper discusses thermal hydraulic calculations for a Gas Test Loop (GTL) system designed to provide a high intensity fast-flux irradiation environment for testing fuels and materials for advanced concept nuclear reactors. To assess the performance of candidate reactor fuels, these fuels must be irradiated under actual fast reactor flux conditions and operating environments, preferably in an existing irradiation facility [1]. Potential users of the GTL include the Generation IV Reactor Program, the Advanced Fuel Cycle Initiative and Space Nuclear Programs

191

Sulphur compounds in a hydraulic ash-disposal system  

International Nuclear Information System (INIS)

In the retorting process of Estonian oil shale over half of the sulphur occurring in the feed shale remains in the solid residue. Sulphide in the form of iron and calcium sulphides is environmentally the most dangerous. This paper discusses the mechanism and the rate of hydrolysis and oxidation reactions of sulphur compounds in the hydraulic ash-disposal system. 3 figs., tab., 4 refs

192

Experimental-based Modelling and Simulation of Water Hydraulic Mechatronics Test Facilities for Motion Control and Operation in Environmental Sensitive Applications` Areas  

DEFF Research Database (Denmark)

The paper presents experimental-based modelling, simulation, analysis and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. The contributions includes results from on-going research projects on fluid power and mechatronics based on tap water hydraulic proportional valves and servo actuators for motion control and power transmission undertaken in co-operation by Technical University, DTU and Cracow University of Technology, CUT. The results of this research co-operation include engineering design and test of simulation models compared with two mechatronic test rig facilities powered by environmental friendly water hydraulic servo actuator system. Test rigs with measurement and data acquisition system were designed and build up with tap water hydraulic components of the Danfoss Nessie® product family. This paper presents selected experimental and identifying test results for a water hydraulic system.

Conrad, Finn

2003-01-01

193

Evaluation of Bulk Modulus of Oil System with Hydraulic Line  

Science.gov (United States)

The aim of the paper is to experimentally measure and ealuate bulk modulus of oil/steel pipe system and oil/hose system. The measurement was performed using experimental device on the basis of a measured pressure difference depending on time. Bulk modulus is evaluated from pressure change with known flow and volume of line. Pressure rise is caused by valve closure at the line end. Furthermore, a mathematical model of the experimental device is created using Matlab SimHydraulics software. Time dependencies of pressure for the oil/steel pipe system and the oil/hose system are simulated on this mathematical model. The simulations are verified by experiment.

Hružík, L.; Vašina, M.; Bure?ek, A.

2013-04-01

194

Hydraulic tests of emergency cooling system: L-Area  

Energy Technology Data Exchange (ETDEWEB)

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

Hinton, J H

1988-01-01

195

Thermal hydraulic tests for reactor safety system -Research on the improvement of nuclear safety-  

International Nuclear Information System (INIS)

The present research aims at the development of the thermal hydraulic verification test technology for the reactor safety system of the conventional and advanced nuclear power plant and the development of the advanced thermal hydraulic measuring techniques. (Author)

196

Engine having hydraulic and fan drive systems using a single high pressure pump  

Science.gov (United States)

An engine comprises a hydraulic system attached to an engine housing that includes a high pressure pump and a hydraulic fluid flowing through at least one passageway. A fan drive system is also attached to the engine housing and includes a hydraulic motor and a fan which can move air over the engine. The hydraulic motor includes an inlet fluidly connected to the at least one passageway.

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

2000-01-01

197

Thermal-Hydraulic Experiments and Modelling for Advanced Nuclear Reactor Systems  

International Nuclear Information System (INIS)

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

198

Modernization of the turbine control technique and the turbine hydraulics aimed to improved maneuverability in the load range, system safety and plant availability, plant transparency for diagnosis and long-term performance  

International Nuclear Information System (INIS)

In the contribution H.Mauell GmbH presents modernization projects for the nuclear power plants Tihange-3 and Doel-4. The project volume included control technique and the turbine hydraulics for the steam turbo generating set including turbine auxiliary devices and two turbine feeding pumps. The modernizations were successfully completed in 2010 and 2011, respectively. The nuclear power plants are trouble-free operated.

199

Developing a Tool Point Control Scheme for a Hydraulic Crane Using Interactive Real-time Dynamic Simulation  

DEFF Research Database (Denmark)

This paper describes the implementation of an interactive real-time dynamic simulation model of a hydraulic crane. The user input to the model is given continuously via joystick and output is presented continuously in a 3D animation. Using this simulation model, a tool point control scheme is developed for the specific crane, considering the saturation phenomena of the system and practical implementation.

Pedersen, Mikkel Melters; Hansen, Michael Rygaard

2010-01-01

200

Application research on hydraulic coke cutting monitoring system based on optical fiber sensing technology  

Science.gov (United States)

With the development of the optical fiber sensing technology, the acoustic emission sensor has become one of the focal research topics. On the basis of studying the traditional hydraulic coke cutting monitoring system, the optical fiber acoustic emission sensor has been applied in the hydraulic coke cutting monitoring system for the first time, researching the monitoring signal of the optical fiber acoustic emission sensor in the system. The actual test results show that using the acoustic emission sensor in the hydraulic coke cutting monitoring system can get the real-time and accurate hydraulic coke cutting state and the effective realization of hydraulic coke cutting automatic monitoring in the Wuhan Branch of Sinopec.

Zhong, Dong; Tong, Xinglin

2014-06-01

 
 
 
 
201

Method for use of hydraulically or electrically controlled solenoids under failed on conditions  

Energy Technology Data Exchange (ETDEWEB)

A method to operate a clutch device in an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and at least one electric machine includes, in response to a failure condition detected within a flow control device configured to facilitate flow of hydraulic fluid for operating the clutch device, selectively preventing the flow of hydraulic fluid from entering the flow control device and feeding the clutch device. Synchronization of the clutch device is initiated when the clutch device is intended for activation, and only if the clutch device is synchronized, the flow of hydraulic fluid is selectively permitted to enter the flow control device to activate the clutch device.

Bolenbaugh, Jonathan M.; Naqi, Syed

2014-07-08

202

Super Twisting Second Order Sliding Mode Control for Position Tracking Control of Hydraulic Drives  

DEFF Research Database (Denmark)

In this paper a control strategy based on second order sliding modes, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD), is proposed. The main target is to overcome problems with linear controllers deteriorating performance due to the strong nonlinearities characterizing VCD's. The proposed controller requires pressure-, valve- and piston position measurements, and is based on the so-called super twisting algorithm and compensation of controlgain nonlinearities. Simulation results demonstrate strong robustness when subjected to large perturbations in coulomb friction.

Schmidt, Lasse; Andersen, Torben Ole

2013-01-01

203

Electro-hydraulic drive system R7 for crude oil production; Alternativer elektro-hydraulischer Tiefpumpenantrieb zur Erdoelgewinnung  

Energy Technology Data Exchange (ETDEWEB)

The article introduces the new electro-hydraulic drive system R7 from Bosch Rexroth as an alternative to the widespread mechanical sucker rod pump. The function and features of the electro-hydraulic drive system are described as well as the technical advantages. Additionally new opportunities of condition monitoring and remote control for the user are shown. In cooperation with the Wintershall Holding GmbH, Bosch Rexroth has started a field test for showing the functionality of the electro-hydraulic R7 unit. Starting in May 2009 with the installation of a sucker rod pump on a selected well of the Wintershall Holding GmbH in Landau (Germany) and the replacing it with the R7-unit in October 2010, a 1 to 1 comparison will be generated. The first practical validation of the electro-hydraulic drive system R7 will be created in terms of production efficiency, operating costs and reliability after 18 month of testing. (orig.)

Schulze, M.; Thomas, W. [Bosch Rexroth AG, Lohr am Main (Germany); Ruttmann, Thomas [Wintershall Holding GmbH, Kassel (Germany)

2011-01-15

204

Role of system characteristics in evolution of pump hydraulic design  

International Nuclear Information System (INIS)

Primary heat transport (PHT) main circuit provides the means for transferring the heat produced in the fuel by circulating heavy water in the main circuit loop by primary coolant pumps (PCPs). The procurement specification of PCPs for 500 MWe pressurised heavy water reactor (PHWR) was prepared based upon the first order hydraulic analysis of the primary heat transport system and accordingly duty point was fixed. With this specification the manufacturer carried out model testing to arrive at optimum size of the impeller followed by determination of pump characteristics curves using full scale impeller during type testing. The duty point thus obtained was higher than specified necessitating the trimming of impeller. However, in order to make use of available higher duty point from system considerations, the duty point was redefined for production of subsequent pumps within specified tolerances governed by manufacturing limitations. PHT main system sizing (piping and feeders) was carried out based upon pump (delivering maximum flow) characteristics curve. Pressure profiles of PHT system at various operating modes were drawn and corresponding power drawn by motor was calculated. The interfacing of reactor coolant main system with hydraulic characteristics of PCP plays a significant role in establishing the requisite capability and capacity of PHT system in performing its intended functions. Therefore the paper traces the evolution of design parameters for PCP and subsequent generation of pressure profiles commensurate with the changes made in power profile including their impact on feeder sizing. The paper also highlights the scope of interaction between process designer and pump manufacturer in formulating a mutually acceptable and efficient hydraulic performance for PCP. (author). 3 refs., 8 figs., 3 tabs

205

Nanocoatings for High-Efficiency Industrial Hydraulic and Tooling Systems  

Energy Technology Data Exchange (ETDEWEB)

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 energy conservation. In mobile hydraulic systems, efficiency gains through low friction would translate into improved fuel economy and fewer greenhouse gas emissions. Stationary hydraulic systems, accordingly, would consume less electrical power. Reduced tooling wear in machining operations would translate to greater operating yields, while lowering the energy consumed during processing. The AlMgB14 nanocoatings technology progressed beyond baseline laboratory tests into measurable energy savings and enhancements to product durability. Three key hydraulic markets were identified over the course of the project that will benefit from implementation: industrial vane pumps, orbiting valve-in-star hydraulic motors, and variable displacement piston pumps. In the vane pump application, the overall product efficiency was improved by as much as 11%. Similar results were observed with the hydraulic motors tested, where efficiency gains of over 10% were noted. For variable displacement piston pumps, overall efficiency was improved by 5%. For cutting tools, the most significant gains in productivity (and, accordingly, the efficiency of the machining process as a whole) were associated with the roughing and finishing of titanium components for aerospace systems. Use of the AlMgB14 nanocoating in customer field tests has shown that the coated tools were able to withstand machining rates as high as 500sfm (limited only by the substrate material), with relatively low flank wear when compared to other industrial offerings. AlMgB14 coated tools exhibited a 60% improvement over similarly applied TiAlN thin films. Furthermore, AlMgB14-based coatings in these particular tests lasted twice as long than their TiAlN counterparts at the 500sfm feed rates. Full implementation of the technology into the industrial hydraulic and cutting tool markets equates to a worldwide energy savings of 46 trillion BTU/year by 2030. U.S.-based GHG emissions associated with the markets identified would fall accordingly, dropping by as much as 50,000 tonnes annually.

Clifton B. Higdon III

2011-01-07

206

Evaluation of Bulk Modulus of Oil System with Hydraulic Line  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The aim of the paper is to experimentally measure and ealuate bulk modulus of oil/steel pipe system and oil/hose system. The measurement was performed using experimental device on the basis of a measured pressure difference depending on time. Bulk modulus is evaluated from pressure change with known flow and volume of line. Pressure rise is caused by valve closure at the line end. Furthermore, a mathematical model of the experimental device is created using Matlab SimHydraulics software. Time...

Bure?ek A.; Vašina M.; Hružík L.

2013-01-01

207

Thermal-hydraulics of lead bismuth for accelerator driven systems  

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: Lead bismuth has been selected as one of the most suitable coolants to be used in accelerator driven systems (ADS) for transmutation of minor actinides. It serves both, as a target material of the spallation source to balance the neutron economy, and as a coolant with high thermal inertia to provide a safe and reliable heat transfer to the secondary power cycle. With the aim to develop the required technologies to enable the later design of such ADS systems, the Karlsruhe Lead bismuth LAboratory KALLA, consisting of three test loops, has been built and set into operation at the Forschungszentrum Karlsruhe since 2000, keeping more than 45 t of PbBi in operation at temperatures up to 550 deg. C. The test program includes oxygen control systems, heat flux simulation tools, electro-magnetic and mechanical pump technologies, heat transfer and flow measurements, reliability and corrosion tests. In a first test campaign, a technology loop called THESYS was built to develop measurement technologies for the acquisition of scalar quantities, like pressures, temperatures, concentrations, and flow rates, as well as velocity fields, which are required for both operational and scientific purposes. THESYS also allowed to perform generic turbulent heat transfer experiments necessary to provide liquid metal adapted turbulent heat transfer models for ADS design analyses. The second loop, the thermalhydraulic loop THEADES with an installed power of 2.5 MW, has been built to conduct prototypical component experiments for beam windows (e.g. MEGAPIE or MYHRRA) or fuel rod configurations. First test results will be reported. The experimental team is supported by a numerical team who studied the thermal hydraulics of the tested components in order to enable a later transfer of the results to industrial systems. Three different types of codes are being improved: lumped parameter codes (e.g. ATHLET) to perform system analyses for lead bismuth in loops, targets, pumps and heat exchangers, CFD codes (e.g. CFX) to analyse local phenomena in thermally highly loaded components, and sub-channel codes (e.g. MATRA) to be used later for fuel assembly design. Heat transfer correlations and turbulence models were checked against measured data for validation. In addition, a direct numerical simulation of selected cases could provide further insight into the nature of turbulence in liquid lead bismuth. The paper is intended to give an overview of the numerous results achieved up to now. (authors)

Thomas Schulenberg; Xu Cheng; Robert Stieglitz [Institute for Nuclear and Energy Technologies, Forschungszentrum Karlsruhe, P.O. Box 3640, 76021 Karlsruhe (Germany)

2005-07-01

208

An adaptive fuzzy dead-zone compensation scheme and its application to electro-hydraulic systems  

Directory of Open Access Journals (Sweden)

Full Text Available The dead-zone is one of the most common hard nonlinearities in industrial actuators and its presence may drastically compromise control systems stability and performance. Due to the possibility to express specialist knowledge in an algorithmic manner, fuzzy logic has been largely employed in the last decades to both control and identification of uncertain dynamical systems. In spite of the simplicity of this heuristic approach, in some situations a more rigorous mathematical treatment of the problem is required. In this work, an adaptive fuzzy controller is proposed for nonlinear systems subject to dead-zone input. The boundedness of all closed-loop signals and the convergence properties of the tracking error are proven using Lyapunov stability theory and Barbalat's lemma. An application of this adaptive fuzzy scheme to an electro-hydraulic servo-system is introduced to illustrate the controller design method. Numerical results are also presented in order to demonstrate the control system performance.

Wallace M. Bessa

2010-03-01

209

Non-linear modelling and optimal control of a hydraulically actuated seismic isolator test rig  

Science.gov (United States)

This paper investigates the modelling, parameter identification and control of an unidirectional hydraulically actuated seismic isolator test rig. The plant is characterized by non-linearities such as the valve dead zone and frictions. A non-linear model is derived and then employed for parameter identification. The results concerning the model validation are illustrated and they fully confirm the effectiveness of the proposed model. The testing procedure of the isolation systems is based on the definition of a target displacement time history of the sliding table and, consequently, the precision of the table positioning is of primary importance. In order to minimize the test rig tracking error, a suitable control system has to be adopted. The system non-linearities highly limit the performances of the classical linear control and a non-linear one is therefore adopted. The test rig mathematical model is employed for a non-linear control design that minimizes the error between the target table position and the current one. The controller synthesis is made by taking no specimen into account. The proposed approach consists of a non-linear optimal control based on the state-dependent Riccati equation (SDRE). Numerical simulations have been performed in order to evaluate the soundness of the designed control with and without the specimen under test. The results confirm that the performances of the proposed non-linear controller are not invalidated because of the presence of the specimen.

Pagano, Stefano; Russo, Riccardo; Strano, Salvatore; Terzo, Mario

2013-02-01

210

Project calculation of the steering mechanism hydraulic servo control in motor vehicles  

Directory of Open Access Journals (Sweden)

Full Text Available Hydraulic servo controls are designed to facilitate rotation in place without providing increased ppower to steering wheels. In the initial design phase, the dimensions required for control systems are usually obtained through the calculation of their load when wheels rotate in place, where the torque is calculated empirically. The starting point in the project calculation is thus to determine the hydraulic power steering torque torsional resistance which is then used to determine the maximum value of force i.e. the torque on the stering wheel. The calculation of the control system servo control consists of determining the basic parameters, the required pump capacity, the main dimensions of the hub and the  pipeline and the conditions for the stability of the system control mechanism. Introduction The aim of the calculation of the steering control system is to determine the basic parameters of its components which ensure the fulfilment of requirements of the control system. Calculations are performed in several stages with a simultaneous  detailed constructive analysis of the control system leading to the best variant. At each stage, design and control calculations of the hydraulic servo of the steering mechanism are performed. The design allows the computation to complete the selection of basic dimensions of the amplifer elements, starting from the approved scheme and the basic building loads of approximate values. Calculations control is carried out to clarify the structural solution and to obtain the output characteristics of the control amplifier which are applied in the  estimation of  potential properties of the structure. Project calculation Baseline data must be sufficiently reliable, ie. must correspond to the construction characteristics of the vehicle design and the control system as well as to service conditions..A proper deterimination of the torque calculation of torsional resistance in wheels is of utmost importance. Moment of resistance to wheel rotation in place The magnitude of the torque required to rotate drive wheels in place, is affected by: 1 load on wheels; 2 coefficient of friction of the tire surface; 3 dimensions and shape of the tire footprint on the surface, as deterimined by the pressure in the tire and its construction; 4 lateral stiffness of the tire; 5 turning radius of drive wheels; 6 angles of inclination of the pin; 7 moment of friction in pins and steering gear mechanism. To achieve the proper torque values of torsional resistance in drive wheels, it is necessary to take into account all these influential factors, as this provides a lower load on the elements in the control system while enabling easier control and reducing the moment of force on the steering wheel. Moment of resistance to rotating drive wheels in place according to Mitin Mitin obtained the coefficient  only for one tire so the use of this formula is practically impossible. Moment of resistance to rotating drive wheels in place according to Taborek Moment of resistance to rotating drive wheels in place according to Lisov This formula takes into account the radius of the tire, but does not take into account the pressure and elastic characteristics of tires. Moment of resistance ito rotating drive wheels in place by Litvinov For the calculation by this formula, it is necessary to know the dependence of the tire footprint surface and the load on it. Moment of resistance to rotating drive wheels in place by Gough Experimental studies have shown that this term is very acceptable. Dimensions of the executive hydraulic cylinder The control amplifier must provide that the wheels rotate in place when the force of the driver on the steering wheel is not above 160 – 200 N in a complete range of the rotation angles from   for the inner wheel to for the outer wheel. Reactive and centering elements of the hydraulic servo control The control system without a hydraulic servo control must have one very important characteristic which is to develop the ability of the driver to feel the road configuration, esp

Zoran ?ukan Majki?

2013-10-01

211

Study on Knowledge -based Intelligent Fault Diagnosis of Hydraulic System  

Directory of Open Access Journals (Sweden)

Full Text Available A general framework of hydraulic fault diagnosis system was studied. It consisted of equipment knowledge bases, real-time databases, fusion reasoning module, knowledge acquisition module and so on. A tree-structure model of fault knowledge was established. Fault nodes knowledge was encapsulated by object-oriented technique. Complete knowledge bases were made including fault bases and diagnosis bases. It could describe the fault positions, the structure of fault, cause-symptom relationships, diagnosis principles and other knowledge. Taking the fault of left and right lifting oil cylinder out of sync for example, the diagnostic results show that the methods were effective.

Xuexia Liu

2012-12-01

212

Scaling of Thermal-Hydraulic Phenomena and System Code Assessment  

International Nuclear Information System (INIS)

In the last five decades large efforts have been undertaken to provide reliable thermal-hydraulic system codes for the analyses of transients and accidents in nuclear power plants. Many separate effects tests and integral system tests were carried out to establish a data base for code development and code validation. In this context the question has to be answered, to what extent the results of down-scaled test facilities represent the thermal-hydraulic behaviour expected in a full-scale nuclear reactor under accidental conditions. Scaling principles, developed by many scientists and engineers, present a scientific technical basis and give a valuable orientation for the design of test facilities. However, it is impossible for a down-scaled facility to reproduce all physical phenomena in the correct temporal sequence and in the kind and strength of their occurrence. The designer needs to optimize a down-scaled facility for the processes of primary interest. This leads compulsorily to scaling distortions of other processes with less importance. Taking into account these weak points, a goal oriented code validation strategy is required, based on the analyses of separate effects tests and integral system tests as well as transients occurred in full-scale nuclear reactors. The CSNI validation matrices are an excellent basis for the fulfilling of this task. Separate effects tests in full scale play here an important role.

213

Vadose zone monitoring strategies to control water flux dynamics and changes in soil hydraulic properties.  

Science.gov (United States)

For monitoring the vadose zone, different strategies can be chosen, depending on the objectives and scale of observation. The effects of non-conventional water use on the vadose zone might produce impacts in porous media which could lead to changes in soil hydraulic properties, among others. Controlling these possible effects requires an accurate monitoring strategy that controls the volumetric water content, ?, and soil pressure, h, along the studied profile. According to the available literature, different monitoring systems have been carried out independently, however less attention has received comparative studies between different techniques. An experimental plot of 9x5 m2 was set with automatic and non-automatic sensors to control ? and h up to 1.5m depth. The non-automatic system consisted of ten Jet Fill tensiometers at 30, 45, 60, 90 and 120 cm (Soil Moisture®) and a polycarbonate access tube of 44 mm (i.d) for soil moisture measurements with a TRIME FM TDR portable probe (IMKO®). Vertical installation was carefully performed; measurements with this system were manual, twice a week for ? and three times per week for h. The automatic system composed of five 5TE sensors (Decagon Devices®) installed at 20, 40, 60, 90 and 120 cm for ? measurements and one MPS1 sensor (Decagon Devices®) at 60 cm depth for h. Installation took place laterally in a 40-50 cm length hole bored in a side of a trench that was excavated. All automatic sensors hourly recorded and stored in a data-logger. Boundary conditions were controlled with a volume-meter and with a meteorological station. ET was modelled with Penman-Monteith equation. Soil characterization include bulk density, gravimetric water content, grain size distribution, saturated hydraulic conductivity and soil water retention curves determined following laboratory standards. Soil mineralogy was determined by X-Ray difractometry. Unsaturated soil hydraulic parameters were model-fitted through SWRC-fit code and ROSETTA based on soil textural fractions. Simulation of water flow using automatic and non-automatic date was carried out by HYDRUS-1D independently. A good agreement from collected automatic and non-automatic data and modelled results can be recognized. General trend was captured, except for the outlier values as expected. Slightly differences were found between hydraulic properties obtained from laboratory determinations, and from inverse modelling from the two approaches. Differences up to 14% of flux through the lower boundary were detected between the two strategies According to results, automatic sensors have more resolution and then they're more appropriated to detect subtle changes of soil hydraulic properties. Nevertheless, if the aim of the research is to control the general trend of water dynamics, no significant differences were observed between the two systems.

Valdes-Abellan, Javier; Jiménez-Martínez, Joaquin; Candela, Lucila

2013-04-01

214

IT-Tools Concept for Simulation and Design of Water Hydraulic Mechatronic Test Facilities for Motion Control and Operation in Environmentally Sensitive Application Areas  

DEFF Research Database (Denmark)

This paper presents a proposed IT-Tools concept for modeling, simulation, analysis and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. The designed test rigs have tap water hydraulic components of the Danfoss Nessie® product family and equipped with a measurement and data acquisition system. Results of the mathematical modeling, simulation and design of the motion control test rigs are presented. Furthermore, the paper presents selected experimental and identifying test results for the water hydraulic test rigs.

Conrad, Finn

2004-01-01

215

Conceptual Design of a Hydraulic Valve Train System  

Directory of Open Access Journals (Sweden)

Full Text Available Variable valve train systems have been brought into focus during recent years as a means to decrease fuel consumption in tomorrow's combustion engines. In this paper an integrated approach, called simulation driven experiments, is utilised in order to aid the development of such highly dynamic systems. Through the use of systematic design methodology, a number of feasible concepts are developed. Critical components are subsequently identified using simulation. In this approach, component behaviour is simulated and validated by measurements on prototype components. These models are unified with complete system models of hydraulically actuated valve trains. In the case of the valve trains systems studied here component models could be validated using comparably simple test set-ups. These models enable the determination of non-critical design parameters in an optimal sense. This results in a number of optimised concepts facilitating an impartial functional concept selection.

J. Pohl

2001-01-01

216

Evaluation of Bulk Modulus of Oil System with Hydraulic Line  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of the paper is to experimentally measure and ealuate bulk modulus of oil/steel pipe system and oil/hose system. The measurement was performed using experimental device on the basis of a measured pressure difference depending on time. Bulk modulus is evaluated from pressure change with known flow and volume of line. Pressure rise is caused by valve closure at the line end. Furthermore, a mathematical model of the experimental device is created using Matlab SimHydraulics software. Time dependencies of pressure for the oil/steel pipe system and the oil/hose system are simulated on this mathematical model. The simulations are verified by experiment.

Bure?ek A.

2013-04-01

217

Hydraulic boundary conditions as a controlling factor in karst genesis: A numerical modeling study on artesian conduit development in gypsum  

Science.gov (United States)

A coupled continuum-pipe flow model is employed to simulate the development of karst conduits in an artesian setting, where aggressive water flows upward from an insoluble aquifer into a gypsum unit. Speleogenetic processes and controlling parameters are identified first for single conduit development. It is demonstrated that transient flow from the conduit into the surrounding fissured system of the rock enhances solutional conduit enlargement. Moreover, single conduit development is found to be highly sensitive to variations in initial diameter and hydraulic gradient. Simulating the solutional enlargement of pipe networks reveals that these two factors determine the resulting conduit pattern. Structural preferences are found to be essential for horizontal conduit development, otherwise flow paths are solely enlarged in vertical direction following the hydraulic gradient. Hydraulic gradients that increase with time can limit the extension or completely inhibit the development of horizontal caves even if lateral conduit development was structurally preferred.

Birk, Steffen; Liedl, Rudolf; Sauter, Martin; Teutsch, Georg

2003-01-01

218

Electromechanical propellant control system actuator  

Science.gov (United States)

New control mechanism technologies are currently being sought to provide alternatives to hydraulic actuation systems. The Propulsion Laboratory at Marshall Space Flight Center (MSFC) is involved in the development of electromechanical actuators (EMA's) for this purpose. Through this effort, an in-house designed electromechanical propellant valve actuator has been assembled and is presently being evaluated. This evaluation will allow performance comparisons between EMA and hydraulics systems. The in-house design consists of the following hardware: a three-phase brushless motor, a harmonic drive, and an output spline which will mate with current Space Shuttle Main Engine (SSME) propellant control valves. A resolver and associated electronics supply position feedback for the EMA. System control is provided by a solid-state electronic controller and power supply. Frequency response testing has been performed with further testing planned as hardware and test facilities become available.

Myers, W. Neill; Weir, Rae Ann

1990-01-01

219

Robust Non-Chattering Observer Based Sliding Control Concept for Electro-Hydraulic Drives  

DEFF Research Database (Denmark)

This paper presents an observer-based sliding mode control concept with chattering reduction, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD's). The proposed control concept requires only common data sheet information and no knowledge on load characteristics. Furthermore the proposed scheme only employ pistonand valve spool positions- and pressure feedback, commonly available in industry. The main target is to overcome problems with linear controllers deteriorating performance due to the inherent nonlinear nature of such systems, without requiring extensive knowledge on system parameters nor advanced control theory. In order to accomplish this task, an integral sliding mode controller designed for the control derivative employing state observation is proposed, based on a generalized reduced order model structure of a VCD with unmatched valve ow- and cylinder asymmetries. It is shown that limited attention can be given to bounds on parameter estimates, that chattering is reduced and the number of tuning parameters is reduced to the level seen in conventional PID schemes. Furthermore, simulation results demonstrate a high level of robustness when subjected to strong perturbations in supply pressure and coulomb friction force, and that tracking accuracy may be reduced to the level of noise. Furthermore, the proposed controller tolerates signicant noise levels, while still remaining stable and accurate.

Schmidt, Lasse; Andersen, Torben Ole

2013-01-01

220

Pneumatic and Hydraulic Systems in Coal Fluidized Bed Combustor  

Directory of Open Access Journals (Sweden)

Full Text Available Problem statement: This study designed the pneumatic and hydraulic systems in coal fluidized bed combustor. These are fluidization of silica sand bed material, Air distributor, centrifugal fan, electric motor power drive and surface heat exchanger. Approach: The effects of increased gas velocity on silica sand and the resultant drag force formed the basic equations in fluidization. Air distributor was introduced to achieve pressure drop across the beds. Results: The constructed centrifugal fan was driven by selected electric motor based on pressure and temperature changes in the reactor. The dimensions of the heat transfer tube were calculated from fluid flow and energy balance equations. The values obtained were as the follows: Fluidization velocity (1.54 m sec-­1, gas velocity through orifice (29.52 m sec-1, the fan electric motor (2 KW, 3 ph at 1500 pm, the steam temperature obtained was 160°C from water ambient temperature of 30°C and tube length 22 m was coiled into levels in the combustor. Conclusion/Recommendation: Precise specifications of pneumatic and hydraulic systems will adequately address the environment concern of coal fired power supply as a method to address epileptic power supply in Nigeria.

Z. O. Opafunso

2009-01-01

 
 
 
 
221

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2010-08-13

222

CFD analysis of pressure loss during flow by hydraulic directional control valve constructed from logic valves  

International Nuclear Information System (INIS)

Highlights: ? Investigating the reduction of flow resistance by hydraulic directional valve. ? Replacing of directional spool valve by logic type valve mounted on the same subplate. ? Verifying the new design by CFD analysis with ANSYS/FLUENT software. ? Allowing an example of the solution to reduce pressure loss over 35–61%. ? Conducting an experimental studies to verify CFD analysis. - Abstract: The aim of this paper is to investigate the reduction of flow resistance in a hydraulic system. The undertaken matter is focused on a spool type directional control valve with pilot operated check valves. In the paper there is a proposition of replacing a 4-way directional control valve with pilot operated check valves by suitable unit consisting of logic valves. Therefore, a body of new directional control valve has been designed. Four logic valves are mounted on the body and closed with a cover on which electromagnetic pilot valve is assembled. The hydraulic ports of the body are in accordance with the standard ISO 4401 – 08-07-0-94, so the proposed new directional control valve can be applied alternatively to a directional spool valve. An important task given during the work is to create the systems of flow paths inside the body, which are assumed to be performed with simple technologies like: drilling, boring and milling. The system of the designed flow paths is verified by CFD analysis with the use of ANSYS/FLUENT program on three-dimensional model. Obtainee-dimensional model. Obtained results are compared with the results of the characteristics given in catalogues and coming from experimental research of the prototype. The difference in pressure loss during flow for the logic valve taken from CFD calculation and the catalogue do not exceed 5%. Presented in the paper directional control valve may operate for volumetric flow rate up to 450 dm3/min and the pressure up to 42 MPa. In the proposed solution, although simple technologies of making flow paths were applied, the pressure losses were reduced over 35%. The developed solution is close to a standard directional spool valve and can be assembled on an identical sub-plate.

223

Transient Thermal Hydraulic Analyses of Heavy Water System  

International Nuclear Information System (INIS)

A research reactor core surrounded by a heavy water (D2O) vessel uses heavy water as a reflector. A Heavy Water System (HWS) is installed to remove the heat generated in heavy water and the vessel itself. The HWS is separated from the primary cooling system of the core. Postulated Initiating Events (PIEs) in the HWS are evaluated for safety purposes. In the present study, transient thermal hydraulic analyses of HWS such as loss of heavy water flow owing to a pump failure, dilution of heavy water owing to a pipe rupture inside a pool, heavy water leakage owing to a pipe rupture outside a pool, and loss of heat removal owing to a secondary cooling system failure are analyzed

224

Control system for NPP powerfull turbines  

International Nuclear Information System (INIS)

A control system for NPP 1000 MW turbines safety is described. The turbine safety system has a hydraulic drive to actuate in case of increasipg of rotational speed of a turbine rotor and an electrohydraulic drce to operate in case of pressure reduction in the lubrication system, axial displacement deviation, etc. The system is highly reliable due to application of a safety system without slide valves and long-term operation of hydraulic controls in guarding conditions; the system epsures multifunctional control with high accuracy and speed due to application of the intricate electronic part, high speed of response with a limited use of high pressure oil due to application of two-pressure pumps, pneumohydraulic accumulators and oil discharge valves. Steady-state serviceability of the system is maintained by devices for valve cooling dawn. A shockless change from electrohydraulic to hydraulic control channels is provided

225

Design, simulation, and testing of a novel hydraulic power take-off system for the Pelamis wave energy converter  

Energy Technology Data Exchange (ETDEWEB)

The economic viability of a wave energy converter depends largely on its power take-off system. Active control of the power take-off is necessary to maximise power capture across a range of sea-states and can also improve survivability. The high force, low speed regime of wave energy conversion makes it a suitable application for high-pressure hydraulics. This paper describes the hydraulic power take-off system employed in the Pelamis wave energy converter. The process of the system's development is presented, including simulation and laboratory tests at 1/7th and fullscale. Results of efficiency measurements are also presented. (author)

Henderson, Ross [Ocean Power Delivery Ltd, Edinburgh, Scotland (United Kingdom)

2006-02-01

226

Optimal hydraulic design of new-type shaft tubular pumping system  

International Nuclear Information System (INIS)

Based on the characteristics of large flow rate, low-head, short annual operation time and high reliability of city flood-control pumping stations, a new-type shaft tubular pumping system featuring shaft suction box, siphon-type discharge passage with vacuum breaker as cutoff device was put forward, which possesses such advantages as simpler structure, reliable cutoff and higher energy performance. According to the design parameters of a city flood control pumping station, a numerical computation model was set up including shaft-type suction box, siphon-type discharge passage, pump impeller and guide vanes. By using commercial CFD software Fluent, RNG ?-? turbulence model was adopted to close the three-dimensional time-averaged incompressible N-S equations. After completing optimal hydraulic design of shaft-type suction box, and keeping the parameters of total length, maximum width and outlet section unchanged, siphon-type discharge passages of three hump locations and three hump heights were designed and numerical analysis on the 9 hydraulic design schemes of pumping system were proceeded. The computational results show that the changing of hump locations and hump heights directly affects the internal flow patterns of discharge passages and hydraulic performances of the system, and when hump is located 3.66D from the inlet section and hump height is about 0.65D (D is the diameter of pump impeller), the new-type shaft tubular pumping system achieves better energy performances. A pumping system model test of the optimal designed scheme was carried out. The result shows that the highest pumping system efficiency reaches 75.96%, and when at design head of 1.15m the flow rate and system efficiency were 0.304m3/s and 63.10%, respectively. Thus, the validity of optimal design method was verified by the model test, and a solid foundation was laid for the application and extension of the new-type shaft tubular pumping system.

227

Optimal hydraulic design of new-type shaft tubular pumping system  

Science.gov (United States)

Based on the characteristics of large flow rate, low-head, short annual operation time and high reliability of city flood-control pumping stations, a new-type shaft tubular pumping system featuring shaft suction box, siphon-type discharge passage with vacuum breaker as cutoff device was put forward, which possesses such advantages as simpler structure, reliable cutoff and higher energy performance. According to the design parameters of a city flood control pumping station, a numerical computation model was set up including shaft-type suction box, siphon-type discharge passage, pump impeller and guide vanes. By using commercial CFD software Fluent, RNG ?-epsilon turbulence model was adopted to close the three-dimensional time-averaged incompressible N-S equations. After completing optimal hydraulic design of shaft-type suction box, and keeping the parameters of total length, maximum width and outlet section unchanged, siphon-type discharge passages of three hump locations and three hump heights were designed and numerical analysis on the 9 hydraulic design schemes of pumping system were proceeded. The computational results show that the changing of hump locations and hump heights directly affects the internal flow patterns of discharge passages and hydraulic performances of the system, and when hump is located 3.66D from the inlet section and hump height is about 0.65D (D is the diameter of pump impeller), the new-type shaft tubular pumping system achieves better energy performances. A pumping system model test of the optimal designed scheme was carried out. The result shows that the highest pumping system efficiency reaches 75.96%, and when at design head of 1.15m the flow rate and system efficiency were 0.304m3/s and 63.10%, respectively. Thus, the validity of optimal design method was verified by the model test, and a solid foundation was laid for the application and extension of the new-type shaft tubular pumping system.

Zhu, H. G.; Zhang, R. T.; Zhou, J. R.

2012-11-01

228

Field investigation on consumer behavior and hydraulic performance of a district heating system in Tianjin, China  

Energy Technology Data Exchange (ETDEWEB)

With the implementation of heat reforms in China, the application of thermostatic radiator valves (TRVs) has been gaining popularity in the new-style district heating systems (DHSs). The objective of this study was to investigate consumer behavior (including regulation of TRVs and opening of windows) and its influences on the hydraulic performance and energy consumption of individuals and the whole system. The concurrence rate of individual behaviors and hydraulic interactions between individuals were analyzed. This study should be helpful to gain a comprehensive understanding of the new DHSs in China and consider a proper design/control strategy for these systems. Questionnaires and field observations of consumer behavior, tests of hydraulic performance, and surveys of energy consumption were carried out in a DHS in Tianjin, which was one of the heat metering and billing demonstration projects in China. The main results of the tests were as follows: water flow performance in apartment-level heating systems were diverse because consumers' behavior was varied and unpredictable, and the hydraulic interaction between consumers living along the line of a vertical pipe was obvious, and was stronger for terminal consumers with their TRVs set to higher values; however, flow variations in the whole DHS, which included 910 households, were relatively constant. A probability analysis was carried out to explain this phenomenon, and the conclusion was drawn that when there were more than 200 consumers, the stochastic consumer regulation behavior would bring less than 10% of total flow variations. Finally, the power consumption of the circulation pump, heat consumption and energy-saving potential of this type of DHS were discussed and some suggestions for TRV regulation and pump operation were made. (author)

Xu, Baoping; Fu, Lin; Di, Hongfa [Department of Building Science, Tsinghua University, Beijing 100084 (China)

2009-02-15

229

Regulation and hydraulic design of highway stormwater drainage system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The present work handles treatment of storm water from highways and its cleaning facilities hydraulic design according to Slovenian and German guidelines and directives. First part contains basic data that we have to take into consideration in order to achieve good hydraulic design for cleaning facilities. Road and highway categorization and their typical features in Slovenia and Germany are also written as basics for runoff hydraulic design. Following, most of the storm water cleaning facili...

Z?ibret, Marko

2006-01-01

230

Experimental Study on Cartesian-Space PD Control for Hydraulic Manipulator  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents Cartesian-space PD control of a hydraulic manipulator. The approach based upon “Virtual spring-damper hypothesis” is composed of virtual spring effects and virtual damper effects in task space. It has been applied to electrically driven robots. This experiment shows the comparison of Cartesian-space control with typical joint-space control in the performance of straight-line motion for the hydraulic manipulator that easily generate movements of manipulator without spending a huge amount of computational cost

Sang-Uk Chon

2014-08-01

231

Global asymptotic stabilization of large-scale hydraulic networks using positive proportional controls  

DEFF Research Database (Denmark)

An industrial case study involving a large-scale hydraulic network underlying a district heating system subject to structural changes is considered. The problem of controlling the pressure drop across the so-called end-user valves in the network to a designated vector of reference values under directional actuator constraints is addressed. The proposed solution consists of a set of decentralized positively constrained proportional control actions. The results show that the closed-loop system always has a globally asymptotically stable equilibrium point independently on the number of end-users. Furthermore, by a proper design of controller gains the closed-loop equilibrium point can be designed to belong to an arbitrarily small neighborhood of the desired equilibrium point. Since there exists a globally asymptotically stable equilibrium point independently on the number of end-users in the system, it is concluded that structural changes can be implemented without risk of introducing instability. In addition, structural changes can be easily implemented due to the decentralized control architecture.

Jensen, Tom NŘrgaard; Wisniewski, Rafal

2014-01-01

232

Active control system for high speed windmills  

Science.gov (United States)

A pump stroke is matched to the operating speed of a high speed windmill. The windmill drives a hydraulic pump for a control. Changes in speed of a wind driven shaft open supply and exhaust valves to opposite ends of a hydraulic actuator to lengthen and shorten an oscillating arm thereby lengthening and shortening the stroke of an output pump. Diminishing wind to a stall speed causes the valves to operate the hydraulic cylinder to shorten the oscillating arm to zero. A pressure accumulator in the hydraulic system provides the force necessary to supply the hydraulic fluid under pressure to drive the actuator into and out of the zero position in response to the windmill shaft speed approaching and exceeding windmill stall speed.

Avery, Don E. (45-437 Akimala St., Honolulu, HI 96744)

1988-01-01

233

Non-linear seismic analysis in NSSS system for SG hydraulic snubber elimination  

International Nuclear Information System (INIS)

In the structural design of nuclear power plants, large bore hydraulic snubbers are used in the steam generator (SG) upper support system due to their ability to accommodate the large thermal movement of the SG during plant heatup/cooldown and yet provide restraint to the SG for dynamic loadings such as postulated piping rupture and seismic events. Due to the complexity of the control valve, hydraulic snubbers are very sensitive to abnormalities or changes in the hydraulic fluid. Additionally, snubber service life and operation are directly influenced by the durability of the snubber seal materials. Each of these factors significantly affects the operability of the hydraulic snubber and contributes to the continuing need to monitor and periodically test the performance of the snubbers. In light of the increasing costs to the utilities on the maintenance and testing of these snubbers, analytical methods were developed in order to eliminate all the large bore SG snubbers through the use of non-linear seismic analysis, innovative hardware design and modification, and component reserve design margins. The benefit of this snubber elimination program is to minimize plant operation costs through reductions in plant outage activities and man-rem exposures resulting from eliminated snubber inspection, testing, maintenance and refurbishment. This paper presents a procedure along with analytical techniques used in the non-linear seismic analysis for the snubber-eliminated supporanalysis for the snubber-eliminated support configuration. Through this non-linear time-history analysis technique, the analysis resulted in, generally, load reductions in the Reactor Coolant Loop (RCL) system since the original analysis was based on a very conservative response spectra analysis technique. Hence the system components are all qualified

234

Developing a Tool Point Control Scheme for a Hydraulic Crane Using Interactive Real-time Dynamic Simulation  

Directory of Open Access Journals (Sweden)

Full Text Available This paper describes the implementation of an interactive real-time dynamic simulation model of a hydraulic crane. The user input to the model is given continuously via joystick and output is presented continuously in a 3D animation. Using this simulation model, a tool point control scheme is developed for the specific crane, considering the saturation phenomena of the system and practical implementation.

Mikkel M. Pedersen

2010-10-01

235

Analysis of core physics and thermal-hydraulics results of control rod withdrawal experiments in the LOFT facility  

International Nuclear Information System (INIS)

Two anticipated transient experiments simulating an uncontrolled control rod withdrawal event in a pressurized water reactor (PWR) were conducted in the Loss-of-Fluid Test (LOFT) Facility at the Idaho National Engineering Laboratory. The scaled LOFT 50-MW(t) PWR includes most of the principal features of larger commercial PWRs. The experiments tested the ability of reactor analysis codes to accurately calculate core reactor physics and thermal-hydraulic phenomena in an integral reactor system

236

Hydraulic mechanism to limit torsional loads between the IUS and space transportation system orbiter  

Science.gov (United States)

The Inertial Upper Stage (IUS) is a two-stage booster used by NASA and the Defense Department to insert payloads into geosynchronous orbit from low-Earth orbit. The hydraulic mechanism discussed here was designed to perform a specific dynamic and static interface function within the Space Transportation System's Orbiter. Requirements, configuration, and application of the hydraulic mechanism with emphasis on performance and methods of achieving zero external hydraulic leakage are discussed. The hydraulic load-leveler mechanism meets the established design requirements for operation in a low-Earth orbit. Considerable testing was conducted to demonstrate system performance and verification that external leakage had been reduced to zero. Following each flight use of an ASE, all hydraulic mechanism components are carefully inspected for leakage. The ASE, including the hydraulic mechanism, has performed without any anomalies during all IUS flights.

Farmer, James R.

1986-01-01

237

Stormwater sediment and bioturbation influences on hydraulic functioning, biogeochemical processes, and pollutant dynamics in laboratory infiltration systems.  

Science.gov (United States)

Stormwater sediments that accumulate at the surface of infiltration basins reduce infiltration efficiencies by physical clogging and produce anoxification in the subsurface. The present study aimed to quantify the influence of stormwater sediment origin (urban vs industrial catchments) and the occurrence of bioturbators (tubificid worms) on the hydraulic functioning, aerobic/anaerobic processes, and pollutant dynamics in stormwater infiltration systems. In laboratory sediment columns, effects of stormwater sediments and tubificids were examined on hydraulic conductivity, microbial processes, and pollutant releases. Significant differences in physical (particle size distribution) and chemical characteristics betoveen the two stormwater sediments led to distinct effects of these sediments on hydraulic and biogeochemical processes. Bioturbation by tubificid worms could increase the hydraulic conductivity in stormwater infiltration columns, but this effect depended on the characteristics of the stormwater sediments. Bioturbation-driven increases in hydraulic conductivity stimulated aerobic microbial processes and enhanced vertical fluxes of pollutants in the sediment layer. Our results showed that control of hydraulic functioning by stormwater sediment characteristics and/ or biological activities (such as bioturbation) determined the dynamics of organic matter and pollutants in stormwater infiltration devices. PMID:19544865

Nogaro, Geraldine; Mermillod-Blondin, Florian

2009-05-15

238

49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.  

Science.gov (United States)

...1(b), except for vehicles using hydraulic system mineral oil. (C) If a separate indicator...labeling —Each vehicle equipped with hydraulic brakes shall have a brake fluid warning statement...The force required for actuation of a hand-operated brake system shall be...

2010-10-01

239

COBRA-SFS, Thermal Hydraulics of Spent Fuel Storage System  

International Nuclear Information System (INIS)

1 - Description of program or function: COBRA-SFS is used for steady- state and transient thermal-hydraulic analysis of spent fuel storage systems as well as other heat transfer and fluid flow problems. It is designed to predict flow and temperature distributions under a wide range of flow conditions, including mixed and natural convection. Two auxiliary programs, RADX1 and RADGEN, generate blackbody view factors and calculate radiation exchange factors for unconsolidated spent fuel assemblies to be supplied as input to COBRA-SFS. 2 - Method of solution: The thermal-hydraulic analysis is separated into two parts - a flow field solution and an energy solution. COBRA-SFS solves a set of incompressible subchannel equations for mass and momentum conservation in the coolant and energy conservation in the fuel rods, solid structures, and coolant. The RECIRC solution method, a Newton-Raphson technique, is used to iteratively solve these equations. Radiation heat transfer between rod and slab surfaces is modeled using detailed radiation exchange factors, which are calculated from the geometry of the problem and the emissivities of the participating surfaces. The subchannel equations are fully implicit in time. 3 - Restrictions on the complexity of the problem - PARAMETER statements presently impose a maxima of: 50 channel gap connections, 40 channels, 20 fuel rods, 40 slab connections, 1 fuel types, 6 assemblies, 9 fuel rods interacting with a channel, 6 fuel nodes per fuel rng with a channel, 6 fuel nodes per fuel rod, 4 axial fuel type divisions. By modifying PARAMETER statements, code dimensioning limits can be changed to fit any given problem, limited only by available storage

240

Second order sliding control with state dependent gain and its application to a hydraulic drive  

DEFF Research Database (Denmark)

The application of sliding modes for control of hydraulic drives appear promising due to strong robustness toward plant uncertainties and disturbances. Especially high order sliding modes may be successfully implemented avoiding the discontinuous control seen in first order sliding controls. However, the very feature of switching about the control target may be undesirable due to finite sampling time and actuator dynamics, and may cause oscillating flow line pressures. This paper discusses a second order sliding controller based on the so-called prescribed convergence algorithm, when used for chattering elimination in hydraulic drive control applications. For this usage the algorithm suffers from poor convergence properties unless a high control gain is chosen, which in turn increases pressure oscillations. To negotiate the combined challenge the controller is extended with a proportional term for improved convergence speed, and the gain of the discontinuous control is made variable according to the control target itself. It is shown that the control error and its derivative are globally convergent to a vicinity of the target via Lyapunov arguments, with accuracy dependent on control parameters, and finite time convergence properties are considered via homogeneity reasoning. Results demonstrate improved control operation compared to the basic algorithm when implemented for position tracking control of a hydraulic drive.

Schmidt, Lasse; Andersen, Torben Ole

2013-01-01

 
 
 
 
241

Apu/hydraulic/actuator Subsystem Computer Simulation. Space Shuttle Engineering and Operation Support, Engineering Systems Analysis. [for the space shuttle  

Science.gov (United States)

Major developments are examined which have taken place to date in the analysis of the power and energy demands on the APU/Hydraulic/Actuator Subsystem for space shuttle during the entry-to-touchdown (not including rollout) flight regime. These developments are given in the form of two subroutines which were written for use with the Space Shuttle Functional Simulator. The first subroutine calculates the power and energy demand on each of the three hydraulic systems due to control surface (inboard/outboard elevons, rudder, speedbrake, and body flap) activity. The second subroutine incorporates the R. I. priority rate limiting logic which limits control surface deflection rates as a function of the number of failed hydraulic. Typical results of this analysis are included, and listings of the subroutines are presented in appendicies.

1975-01-01

242

Thermal hydraulic design of safety grade decay heat removal system  

International Nuclear Information System (INIS)

In nuclear reactor, decay heat has to be removed with very high reliability. In Prototype Fast Breeder Reactor (PFBR) this is achieved by providing highly reliable Safety Grade Decay Heat Removal System (SGDHRS) in addition to the normal heat removal path. The SGDHRS consists of 4 independent circuits, each consisting of a sodium to sodium heat exchanger (DHX) and a sodium to Air Heat Exchanger (AHX). The DHX is a shell and tube type heat exchanger dipped in the hot pool of the reactor. The AHX is a finned tube sodium to air heat exchanger. Preliminary design of SGDHRS has been carried out by using one-dimensional model for the decay heat removal circuit with point models for its heat exchangers. Since the SGDHRS is a safety related system and its capacity dictates the maximum temperatures seen by various hot structures, it is essential to accurately estimate its capacity. Towards this multi-dimensional analyses have been carried out for important components of the system. This paper discusses about the thermal hydraulic models of SGDHRS components like DHX, AHX etc, computer codes used for the analyses and the results obtained. (authors)

243

Lead coolant test facility systems design, thermal hydraulic analysis and cost estimate  

International Nuclear Information System (INIS)

The Idaho National Laboratory prepared a preliminary technical and functional requirements (T and FR), thermal hydraulic design and cost estimate for a lead coolant test facility. The purpose of this small scale facility is to simulate lead coolant fast reactor (LFR) coolant flow in an open lattice geometry core using seven electrical rods and liquid lead or lead–bismuth eutectic coolant. Based on review of current world lead or lead–bismuth test facilities and research needs listed in the Generation IV Roadmap, five broad areas of requirements were identified as listed below: •Develop and demonstrate feasibility of submerged heat exchanger. •Develop and demonstrate open-lattice flow in electrically heated core. •Develop and demonstrate chemistry control. •Demonstrate safe operation. •Provision for future testing. This paper discusses the preliminary design of systems, thermal hydraulic analysis, and simplified cost estimated. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 4200 °C. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M (in 2006 $). It is also estimated that the facility will require two years to be constructed and ready for operation.

244

Lead Coolant Test Facility Systems Design, Thermal Hydraulic Analysis and Cost Estimate  

Energy Technology Data Exchange (ETDEWEB)

The Idaho National Laboratory prepared a preliminary technical and functional requirements (T&FR), thermal hydraulic design and cost estimate for a lead coolant test facility. The purpose of this small scale facility is to simulate lead coolant fast reactor (LFR) coolant flow in an open lattice geometry core using seven electrical rods and liquid lead or lead-bismuth eutectic coolant. Based on review of current world lead or lead-bismuth test facilities and research needs listed in the Generation IV Roadmap, five broad areas of requirements were identified as listed: (1) Develop and Demonstrate Feasibility of Submerged Heat Exchanger; (2) Develop and Demonstrate Open-lattice Flow in Electrically Heated Core; (3) Develop and Demonstrate Chemistry Control; (4) Demonstrate Safe Operation; and (5) Provision for Future Testing. This paper discusses the preliminary design of systems, thermal hydraulic analysis, and simplified cost estimate. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 4200 C. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M (in 2006 $). It is also estimated that the facility will require two years to be constructed and ready for operation.

Soli Khericha; Edwin Harvego; John Svoboda; Ryan Dalling

2012-01-01

245

Lead coolant test facility systems design, thermal hydraulic analysis and cost estimate  

Energy Technology Data Exchange (ETDEWEB)

The Idaho National Laboratory prepared a preliminary technical and functional requirements (T and FR), thermal hydraulic design and cost estimate for a lead coolant test facility. The purpose of this small scale facility is to simulate lead coolant fast reactor (LFR) coolant flow in an open lattice geometry core using seven electrical rods and liquid lead or lead-bismuth eutectic coolant. Based on review of current world lead or lead-bismuth test facilities and research needs listed in the Generation IV Roadmap, five broad areas of requirements were identified as listed below: Bullet Develop and demonstrate feasibility of submerged heat exchanger. Bullet Develop and demonstrate open-lattice flow in electrically heated core. Bullet Develop and demonstrate chemistry control. Bullet Demonstrate safe operation. Bullet Provision for future testing. This paper discusses the preliminary design of systems, thermal hydraulic analysis, and simplified cost estimated. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 4200 Degree-Sign C. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M (in 2006 $). It is also estimated that the facility will require two years to be constructed and ready for operation.

Khericha, Soli, E-mail: slk2@inel.gov [Battelle Energy Alliance, LLC, Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Harvego, Edwin; Svoboda, John; Evans, Robert [Battelle Energy Alliance, LLC, Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Dalling, Ryan [ExxonMobil Gas and Power Marketing, Houston, TX 77069 (United States)

2012-01-15

246

Water hydraulic applications in hazardous environments  

International Nuclear Information System (INIS)

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

247

Water hydraulic applications in hazardous environments  

International Nuclear Information System (INIS)

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

248

Optimal Control for a Parallel Hybrid Hydraulic Excavator Using Particle Swarm Optimization  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Optimal control using particle swarm optimization (PSO) is put forward in a parallel hybrid hydraulic excavator (PHHE). A power-train mathematical model of PHHE is illustrated along with the analysis of components' parameters. Then, the optimal control problem is addressed, and PSO algorithm is introduced to deal with this nonlinear optimal problem which contains lots of inequality/equality constraints. Then, the comparisons between the optimal control and rule-based one are made, and the res...

Wang, Dong-yun; Guan, Chen

2013-01-01

249

Hydraulic drives catch up on control and energy efficiency; Hydraulikantriebe holen auf bei Steuerbarkeit und Energieeffizienz  

Energy Technology Data Exchange (ETDEWEB)

Due to control and energy efficiency hydraulic drives with differential cyclinders are as good as electromechanical linear shafts. Condition is the integration of a hybrid valve changing between standard switches during force formation and regenerative switches during fast motions. (orig./GL)

Kolvenbach, Hansgeorg; Esser, Michael [Parker Hannifin GmbH, Kaarst (Germany). Hydraulic Controls Div. Europe

2010-09-13

250

The SNS Resonance Control Cooling System Control Valve Upgrade Performance  

International Nuclear Information System (INIS)

The normal-conducting linac of the Spallation Neutron Source (SNS) uses 10 separate Resonance Control Cooling System (RCCS) water skids to control the resonance of 6 Drift Tube Linac (DTL) and 4 Coupled Cavity Linac (CCL) accelerating structures. The RCCS water skids use 2 control valves; one to regulate the chilled water flow and the other to bypass water to a chilled water heat exchanger. These valves have hydraulic actuators that provide position and feedback to the control system. Frequency oscillations occur using these hydraulic actuators due to their coarse movement and control of the valves. New pneumatic actuator and control positioners have been installed on the DTL3 RCCS water skid to give finer control and regulation of DTL3 cavity temperature. This paper shows a comparison of resonance control performance for the two valve configurations.

251

Global stabilization of large-scale hydraulic networks with quantized and positive proportional controls  

DEFF Research Database (Denmark)

The problem considered here is output regulation of a large-scale hydraulic network where the structure of the network is subject to change and where the actuation is subject to a non-negativity constraint. Previous results have shown that semi-global practical output regulation is achievable using a set of decentralised, logarithmic quantised and constrained control actions with properly designed quantisation parameters. That is, an attractor set with a compact basin of attraction exists. Subsequently, the basin can be increased by increasing the control gains. In our work, this result is extended by showing that an attractor set with a global basin of attraction exists for arbitrary values of positive control gains, given that the upper level of the quantiser is properly designed. Furthermore, the proof is given for general monotone quantisation maps. Since the basin of attraction is global and the result is independent on the size of the network, this shows that structural changes can be implemented without destabilising the closed-loop system.

Jensen, Tom NŘrgaard; Wisniewski, Rafal

2013-01-01

252

Characterization of Hydraulically Significant Discontinuities in Mudrocks at the Waste Control Specialists (WCS) Site, West Texas  

Science.gov (United States)

Triassic mudrocks of the Dockum Group (Cooper Canyon Formation) host four, below-grade landfills at the Waste Control Specialists (WSC) site in Andrews County, Texas, including: a hazardous waste landfill and three radioactive waste landfills. At many radioactive waste disposal facilities, the long-term performance of the facility may be influenced by the transport of radionuclides through interconnected fracture networks. WCS developed an integrated geologic mapping and hydraulic testing program to evaluate the hydraulic significance of discontinuities within Dockum rocks. At the WCS site, the Dockum consists of mudrocks with sparse siltstone/sandstone interbeds that developed in a semi-arid environment from an ephemeral meandering fluvial system. Sedimentary studies reveal that the mudrocks are ancient floodplain vertisols (soils with swelling clays) and siltstone/sandstone interbeds are fluvial channel deposits that were frequently subaerially exposed. Rock discontinuities, including fractures, were mapped during the excavation of the WCS radioactive waste landfills along vertical faces prepared by the construction contractor. Face locations were selected to insure nearly complete vertical coverage for each landfill. Individual discontinuities were mapped and their strike, dip, length, roughness, curvature, staining, and evidence of displacement were described. In the three radioactive waste disposal landfills, over 1750 discontinuities across 35 excavated faces were mapped and described, where each face was nominally 8 to 10 ft tall and 50 to 100 ft long. On average, the orientation of the discontinuities was horizontal, and no other significant trends were observed. Mapping within the landfill excavations shows that most discontinuities within Dockum rocks are horizontal, concave upward, slickensided surfaces that developed in the depositional environment, as repeated wetting and drying cycles led to shrinking and swelling of floodplain vertisols. Fractures that showed staining (a possible indicator of past or present hydraulic activity) are rare, vertical to near-vertical, and occur mainly in, and adjacent to, mechanically stiff siltstone and sandstone interbeds. No interconnected fracture networks were observed. A series of pressurized air tests were conducted to evaluate fracture interconnectivity at and below the landfill facilities. Three pairs of vertical and three pairs of inclined boreholes were tested at depths ranging from 40 to 215 feet below ground surface. Borehole packers and volume-displacement tools were placed in each borehole to isolate the injection and observation horizons and minimize borehole storage effects, respectively. Injection pressures ranged from 1 to 5 psig. Pressures within the injection boreholes quickly stabilized and slowly decayed due to porous media flow, while no pressure changes occurred in the observation boreholes. These tests confirm the absence of hydrologically significant fracture networks in the subsurface at the WCS site.

Kuszmaul, J. S.; Holt, R. M.; Powers, D. W.; Beauheim, R.; Pickens, J. F.; grisak, G. E.; Hughes, E.; Cook, S.

2011-12-01

253

Macrocalibration in the process of hydraulic modelling of water supply systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The thesis presents an integrated approach to hydraulic modelling of water supply systems, which is mostly based on our own research. The starting phase of hydraulic modelling requires appropriate setting up of a geographic information system and preparation of databases of all entities. This is today crucial for efficient management of water supply systems as far as technical as well as economic and legal aspects are concerned. Appropriate management of data on a water supply ...

S?antl, Sas?o

2007-01-01

254

Thermal-Hydraulic Experiments and Modelling for Advanced Nuclear Reactor Systems  

International Nuclear Information System (INIS)

The objectives of the project are to study thermal hydraulic characteristics of reactor primary system for the verification of the reactor safety and to evaluate new safety concepts of new safety design features. To meet the research goal, several thermal hydraulic experiments were performed and related thermal hydraulic models were developed with the experimental data which were produced through the thermal hydraulic experiments. Followings are main research topics; - Multi-dimensional Phenomena in a Reactor Vessel Downcomer - Condensation Load and Thermal Mixing in the IRWST - Development of Thermal-Hydraulic Models for Two-Phase Flow - Development of Measurement Techniques for Two-Phase Flow - Supercritical Reactor T/H Characteristics Analysis From the above experimental and analytical studies, new safety design features of the advanced power reactors were verified and lots of the safety issues were also resolved

255

An adaptive fuzzy dead-zone compensation scheme and its application to electro-hydraulic systems  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The dead-zone is one of the most common hard nonlinearities in industrial actuators and its presence may drastically compromise control systems stability and performance. Due to the possibility to express specialist knowledge in an algorithmic manner, fuzzy logic has been largely employed in the las [...] t decades to both control and identification of uncertain dynamical systems. In spite of the simplicity of this heuristic approach, in some situations a more rigorous mathematical treatment of the problem is required. In this work, an adaptive fuzzy controller is proposed for nonlinear systems subject to dead-zone input. The boundedness of all closed-loop signals and the convergence properties of the tracking error are proven using Lyapunov stability theory and Barbalat's lemma. An application of this adaptive fuzzy scheme to an electro-hydraulic servo-system is introduced to illustrate the controller design method. Numerical results are also presented in order to demonstrate the control system performance.

Wallace M., Bessa; Max S., Dutra; Edwin, Kreuzer.

2010-03-01

256

How far can various control options take us in terms of increased hydraulic capacity under wet weather conditions?  

DEFF Research Database (Denmark)

Many modelling studies have demonstrated that the hydraulic capacity of the WWTP can be improved by introducing various real time control options, however few studies have demonstrated how effective these controls are in the real world.

Sharma, Anitha Kumari; Guildal, T.

257

Hydraulic Car  

Science.gov (United States)

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

Workshop, Watsonville E.

2011-01-01

258

Hydraulic simulation of the systems of a nuclear power plant for charges calculation in piping  

International Nuclear Information System (INIS)

This work presents a general description of the methodology used by the ENACE S.A. Fluids Working Group for hydraulics simulation of a nuclear power plant system for the calculation charges in piping. (Author)

259

Material fatigue data obtained by card-programmed hydraulic loading system  

Science.gov (United States)

Fatigue tests using load distributions from actual loading histories encountered in flight are programmed on punched electronic accounting machine cards. With this hydraulic loading system, airframe designers can apply up to 55 load levels to a test specimen.

Davis, W. T.

1967-01-01

260

RESEARCH ON HYDRAULIC SERVO AMPLIFIERS USED IN MARINE SYSTEMS  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents numerical simulations for the mecano-hydraulic servoamplifier with a special kind of distributor. This distributor has different covering for the admission and evacuation flow. The purpose of this kind of distributor is to diminuate the high frequency auto-oscillations of the servoamplifier.

Ali BEAZIT

2010-06-01

 
 
 
 
261

Hydraulic balancing of a control component within a nuclear reactor  

International Nuclear Information System (INIS)

A reactor control component includes an inner conduit, for instance containing neutron absorber elements, adapted for longitudinal movement within an outer guide duct. A transverse partition partially encloses one end of the conduit and meets a transverse wall within the guide duct when the conduit is fully inserted into the reactor core. A tube piece extends from the transverse partition and is coaxially aligned to be received within a tubular receptacle which extends from the transverse wall. The tube piece and receptacle cooperate in engagement to restrict the flow and pressure of coolant beneath the transverse partition and thereby minimize upward forces tending to expel the inner conduit

262

Fault Diagnosis for Nonlinear Hydraulic-Mechanical Drilling Pipe Handling System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Leakage and increased friction are common faults in hydraulic cylinders that can have serious consequences if they are not detected at early stage. In this paper, the design of a fault detector for a nonlinear hydraulic mechanical system is presented. By considering the system in steady state, two residual signals are generated and analysed with a composite hypothesis test which accommodates for unknown parameters. The resulting detector is able to detect abrupt changes i...

Choux, Martin; Blanke, Mogens

2011-01-01

263

Space Transportation System solid rocket booster thrust vector control system  

Science.gov (United States)

The Solid Rocket Booster, Thrust Vector Control (TVC) system was designed in accordance with the following requirements: self-contained power supply, failsafe operation, 20 flight uses after exposure to seawater landings, optimized cost, and component interchangeability. Trade studies were performed which led to the selection of a recirculating hydraulic system powered by Auxiliary Power Units (APU) which drive the hydraulic actuators and gimbal the solid rocket motor nozzle. Other approaches for the system design were studied in arriving at the recirculating hydraulic system powered by an APU. These systems must withstand the imposed environment and be usable for a minimum of 20 Space Transportation System flights with a minimum of refurbishment. The TVC system completed the required qualification and verification tests and is certified for the intended application. Substantiation data include analytical and test data.

Verble, A. J., Jr.; Mccool, A. A.; Potter, J. H.

1980-01-01

264

Electric vehicle regenerative antiskid braking and traction control system  

Science.gov (United States)

An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydraulic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control. 10 figs.

Cikanek, S.R.

1995-09-12

265

Finite-time convergent continuous control design based on sliding mode algorithms with application to a hydraulic drive  

DEFF Research Database (Denmark)

Sliding modes impose strong robustness toward parametric plant uncertainties and disturbances and provide for accurate tracking performance in control systems. However, in physical systems the application of sliding modes may give rise to undesirable chattering of the control signal due to actuator dynamics, possible excitation of unmodelled dynamics and structural resonant modes of load systems, etc. This may be avoided by application of smoothing functions imposing boundary layers on the control constraint, or by carrying out the design in relation to the control derivative. However, such boundary layers introduce additional design parameters and actuator dynamics may not allow the desired control accuracy to be reached. In this paper continuous controllers are proposed, with the designs taking their offset in some well-known sliding controllers. The proposed controllers preserve the finite-time convergence properties known from sliding control while at the same time avoiding control chattering, however, onthe cost of robustness. Experimental results confirm the announced properties when applied to a hydraulic valve-cylinder drive, and demonstrates superior performance over conventional linear controllers.

Schmidt, Lasse; Andersen, Torben Ole

2014-01-01

266

Thermal-hydraulic characteristics of a combustion engineering system 80 steam generator. Volume 2. Appendix A  

International Nuclear Information System (INIS)

The Comparative Thermal-Hydraulic Evaluation of Steam Generators program represents an analytical investigation of the thermal-hydraulic characteristics of four PWR steam generators. The analytical tool utilized in this investigation is the CALIPSOS code, a three-dimensional flow distribution code. This report presents the steady state thermal-hydraulic characteristics on the secondary side of a Combustion Engineering System 80 steam generator. Details of the CALIPSOS model with accompanying assumptions, operating parameters, and transport correlations are identified. Comprehensive graphical and numerical results are presented to facilitate the desired comparison with other steam generators analyzed by the same flow distribution code

267

Safety implications of control systems  

International Nuclear Information System (INIS)

The Safety Implications of Control Systems Program has three major activities in support of USI-A47. The first task is a failure mode and effects analysis of all plant systems which may potentially induce control system disturbance that have safety implications. This task has made a preliminary study of overfill events and recommended cases for further analysis on the hybrid simulator. Work continues on overcooling and undercooling. A detailed investigation of electric power network is in progress. LERs are providing guidance on important failure modes that will provide initial conditions for further simulator studies. The simulator taks is generating a detailed model of the control system supported by appropriate neutronics, hydraulics, and thermodynamics submodels of all other principal plant components. The simulator is in the last stages of development. Checkout calculations are in progress to establish model stability, robustness, and qualitative credibility. Verification against benchmark codes and plant data will follow

268

Discrete Displacement Hydraulic Power Take-Off System for the Wavestar Wave Energy Converter  

DEFF Research Database (Denmark)

The Wavestar Wave Energy Converter (WEC) is a multiple absorber concept, consisting of 20 hemisphere shaped floats attached to a single platform. The heart of the Wavestar WEC is the Power Take-Off (PTO) system, converting the wave induced motion of the floats into a steady power output to the grid. In the present work, a PTO based on a novel discrete displacement fluid power technology is explored for the Wavestar WEC. Absorption of power from the floats is performed by hydraulic cylinders, supplying power to a common fixed pressure system with accumulators for energy smoothing. The stored pressure energy is converted into electricity at a steady pace by hydraulic motors and generators. The storage, thereby, decouples the complicated process of wave power absorption from power generation. The core for enabling this PTO technology is implementing a near loss-free force control of the energy absorbing cylinders. This is achieved by using special multi-chambered cylinders, where the different chambers may be connected to the available system pressures using fast on/off valves. Resultantly, a Discrete Displacement Cylinder (DDC) is created, allowing near loss free discrete force control. This paper presents a complete PTO system for a 20 float Wavestar based on the DDC. The WEC and PTO is rigorously modeled from incident waves to the electric output to the grid. The resulting model of +600 states is simulated in different irregular seas, showing that power conversion efficiencies above 70% from input power to electrical power is achievable for all relevant sea conditions.

Hansen, Rico Hjerm; Kramer, Morten

2013-01-01

269

Application of flow network models of SINDA/FLUINT{sup TM} to a nuclear power plant system thermal hydraulic code  

Energy Technology Data Exchange (ETDEWEB)

In order to enhance the dynamic and interactive simulation capability of a system thermal hydraulic code for nuclear power plant, applicability of flow network models in SINDA/FLUINT{sup TM} has been tested by modeling feedwater system and coupling to DSNP which is one of a system thermal hydraulic simulation code for a pressurized heavy water reactor. The feedwater system is selected since it is one of the most important balance of plant systems with a potential to greatly affect the behavior of nuclear steam supply system. The flow network model of this feedwater system consists of condenser, condensate pumps, low and high pressure heaters, deaerator, feedwater pumps, and control valves. This complicated flow network is modeled and coupled to DSNP and it is tested for several normal and abnormal transient conditions such turbine load maneuvering, turbine trip, and loss of class IV power. The results show reasonable behavior of the coupled code and also gives a good dynamic and interactive simulation capabilities for the several mild transient conditions. It has been found that coupling system thermal hydraulic code with a flow network code is a proper way of upgrading simulation capability of DSNP to mature nuclear plant analyzer (NPA). 5 refs., 10 figs. (Author)

Chung, Ji Bum [Institute for Advanced Engineering, Yongin (Korea, Republic of); Park, Jong Woon [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

1998-12-31

270

Plant hydraulic controls over ecosystem responses to climate-enhanced disturbances  

Science.gov (United States)

Climate-enhanced disturbances such as drought and insect infestation range in severity, contributing minor to severe stress to forests including forest mortality. While neither form of disturbance has been unambiguously implicated as a mechanism of mortality, both induce changes in water, carbon, and nutrient cycling that are key to understanding forest ecosystem response to, and recovery from, disturbance. Each disturbance type has different biophysical, ecohydrological, and biogeochemical signatures that potentially complicate interpretation and development of theory. Plant hydraulic function is arguably a unifying control over these responses to disturbance because it regulates stomatal conductance, leaf biochemistry, carbon (C) uptake and utilization, and nutrient cycling. We demonstrated this idea by focusing on water and C, including non-structural (NSC), resources, and nitrogen (N) uptake across a spectrum of forest ecosystems (e.g., northern temperate mixed forests, lodgepole pine forests in the Rocky Mountains, and pinon pine - juniper woodlands in New Mexico) using the Terrestrial Regional Ecosystem Exchange Simulator (TREES). TREES is grounded in the biophysics of water movement through soil and plants, respectively via hydraulic conductivity of the soil and cavitation of xylem. It combines this dynamic plant hydraulic conductance with canopy biochemical controls over photosynthesis, and the dynamics of structural and non-structural carbon through a carbon budget that responds to plant hydraulic status. As such, the model can be used to develop testable hypotheses on a multitude of disturbance and recovery responses including xylem dysfunction, stomatal and non-stomatal controls on photosynthesis and carbon allocation, respiration, and allocation to defense compounds. For each of the ecosystems we constrained and evaluated the model with allometry, sap flux and/or eddy covariance data, leaf gas exchange measurements, and vulnerability to cavitation data. Disturbances included declining water tables and canopy defoliators (northern temperature forests), bark beetles and associated blue-stain fungi (coniferous forests), and prolonged drought with bark beetles (semi-arid woodland). We show that C dynamics in trees that experience water-limitation, insect attack, or a combination of both disturbance types cannot be explained solely from hydraulic status or NSC, but are better explained by a combination of both in conjunction with N uptake. Results show that the use of plant hydraulics can yield parsimonious explanations of biophysical, ecohydrological, and biogeochemical responses to disturbance.

Mackay, D. S.; Ewers, B. E.; Reed, D. E.; Pendall, E.; McDowell, N. G.

2012-12-01

271

Comparison between InfoWorks hydraulic results and a physical model of an urban drainage system.  

Science.gov (United States)

Urban drainage systems are frequently analysed using hydraulic modelling software packages such as InfoWorks CS or MIKE-Urban. The use of such modelling tools allows the evaluation of sewer capacity and the likelihood and impact of pluvial flood events. Models can also be used to plan major investments such as increasing storage capacity or the implementation of sustainable urban drainage systems. In spite of their widespread use, when applied to flooding the results of hydraulic models are rarely compared with field or laboratory (i.e. physical modelling) data. This is largely due to the time and expense required to collect reliable empirical data sets. This paper describes a laboratory facility which will enable an urban flood model to be verified and generic approaches to be built. Results are presented from the first phase of testing, which compares the sub-surface hydraulic performance of a physical scale model of a sewer network in Yorkshire, UK, with downscaled results from a calibrated 1D InfoWorks hydraulic model of the site. A variety of real rainfall events measured in the catchment over a period of 15 months (April 2008-June 2009) have been both hydraulically modelled and reproduced in the physical model. In most cases a comparison of flow hydrographs generated in both hydraulic and physical models shows good agreement in terms of velocities which pass through the system. PMID:23863430

Rubinato, Matteo; Shucksmith, James; Saul, Adrian J; Shepherd, Will

2013-01-01

272

46 CFR 58.30-10 - Hydraulic fluid.  

Science.gov (United States)

...2010-10-01 2010-10-01 false Hydraulic fluid. 58.30-10 Section 58...and Control Systems § 58.30-10 Hydraulic fluid. (a) The requirements...inspection. (b) The fluid used in hydraulic power transmission systems shall...

2010-10-01

273

Proceedings of the 1991 national conference on hydraulic engineering  

International Nuclear Information System (INIS)

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

274

Summary and evaluation of available hydraulic property data for the Hanford Site unconfined aquifer system  

International Nuclear Information System (INIS)

Improving the hydrologic characterization of the Hanford Site unconfined aquifer system is one of the objectives of the Hanford Site Ground-Water Surveillance Project. To help meet this objective, hydraulic property data available for the aquifer have been compiled, mainly from reports published over the past 40 years. Most of the available hydraulic property estimates are based on constant-rate pumping tests of wells. Slug tests have also been conducted at some wells and analyzed to determine hydraulic properties. Other methods that have been used to estimate hydraulic properties of the unconfined aquifer are observations of water-level changes in response to river stage, analysis of ground-water mound formation, tracer tests, and inverse groundwater flow models

275

Electro-hydraulic load simulator device for control rod drives of HTRs  

International Nuclear Information System (INIS)

This article describes the structure and the mode of function of an electro-hydraulic cylinder driving mechanism for the simulation of fuel rod forces during insertion into the pebble bed core of a THTR-type reactor. The force simulation system is necessary for testing and adjusting of the pneumatic driving mechanism of the fuel rods before they are installed in the reactor. (orig.)

276

46 CFR 62.35-50 - Tabulated monitoring and safety control requirements for specific systems.  

Science.gov (United States)

...Specific Systems (Note 1) System Service Instrumentation...shafting Stern tube oil tank level Low Line...controllable pitch propeller Hydraulic oil Pressure High, Low...General, control and alarm systems Power supply...

2010-10-01

277

Role of fracture zones in controlling hydraulic head and groundwater flow - experience from Site Characterization Program in Finland  

International Nuclear Information System (INIS)

The preliminary site investigations for the final disposal of HLW produced by TVO have been carried out during 1987-1992 in five areas. All the areas consist of Precambrian crystallite bedrock. The aim of these studies has been to identify and characterize geological structures, especially fractures and fracture zones with high hydraulic conductivity in order to study groundwater flow phenomena. Measured values of hydraulic head in packed-off sections of the boreholes have produced valuable information about the existence of hydraulically conductive fracture zones and their effects on spatial changes in hydraulic head and groundwater flow. The aim of this paper is to present qualitatively, without numerical simulations, how some main fracture zones control hydraulic head and groundwater flow in Romuvaara investigation area in Kuhmo, Finland

278

Analysis of core physics and thermal-hydraulics results of control rod withdrawal experiments in the LOFT facility  

International Nuclear Information System (INIS)

Two anticipated transient experiments simulating an uncontrolled control rod withdrawal event in a pressurized water reactor (PWR) were conducted in the Loss-of-Fluid Test (LOFT) Facility at the Idaho National Engineering Laboratory. The scaled LOFT 50-MW(t) PWR includes most of the principal features of larger commercial PWRs. The experiments tested the ability of reactor analysis codes to accurately calculate core reactor physics and thermal-hydraulic phenomena in an integral reactor system. The initial conditions and scaled operating parameters for the experiments were representative of those expected in a commercial PWR. In both experiments, all four LOFT control rod assemblies were withdrawn at a reactor power of 37.5 MW and a system pressure of 14.8 MPa

279

Polymer-based micro flow sensor for dynamical flow measurements in hydraulic systems  

Science.gov (United States)

In this paper we present a micro flow sensor from a polymer for dynamical flow measurements in hydraulic systems. The flow sensor is based on the thermal anemometric principle and consists of two micro-structured housing shells from polysulfone (PSU) which form a small fluidic channel with a cross-section of 580 µm × 400 µm. In between there is a thin polyimide membrane supporting three gold track structures forming an electrical heater and two resistive thermometers which allows the detection of the flow direction, too. The complete sensor is inserted into the hydraulic system, but only a small bypass flow is directed through the fluidic channel by means of a special splitting system. Due to its small heat capacity, the sensor is suitable to detect flow pulsations up to about 1200 Hz which allows the sensor to be used for the condition monitoring or preventive maintenance of hydraulic systems.

Ahrens, R.; Festa, M.

2010-06-01

280

A thermo-hydraulic wax actuation system for high force and large displacement applications  

Science.gov (United States)

An actuation system, making use of paraffin wax as a smart material, has been developed for high force, large displacement applications. Wax actuators exploit the significant volumetric expansion (typically between 10 and 15%) experienced during the solid to liquid phase change of paraffin wax. When contained, this expansion results in considerable hydrostatic pressure. Traditionally, wax actuators are designed such that the wax acts directly, via a compliant seal, on an output device such as a piston. We propose using an additional intermediate (passive) fluid to transmit pressure to a separate remote actuator. In essence, we propose a solid-state 'pump' for hydraulic actuation, with no moving parts and which requires no maintenance. The pump makes use of paraffin wax pellets, submerged in hydraulic fluid. The pellets are encapsulated in silicone rubber to prevent contamination of the hydraulic fluid. Upon melting, the volumetric expansion is used to displace the hydraulic working fluid, which is in turn used to drive a conventional hydraulic actuator. Making use of only 65g of paraffin wax, heated from room temperature to 80ÂşC, the pump generated a blocked pressure of 45MPa and displaced 15.7ml of hydraulic fluid. The pump was used to drive a commercial actuator, and achieved a free stroke of 24.4mm and a blocked force of approximately 29kN.

Long, Craig S.; Loveday, Philip W.

2007-04-01

 
 
 
 
281

Development study on hydraulic three-dimensional seismic isolation system applied to advanced nuclear power plant. Development study on hydraulic rocking suppression system  

International Nuclear Information System (INIS)

Three-dimensional (3D) seismic isolation devices have been developed for the base isolation system of the Fast Breeder Reactor (FBR) that is an advanced nuclear reactor power plant building. The developed seismic isolation system consists of the hydraulic type vertical springs with rocking suppression mechanism and the laminated rubber bearings for horizontal direction. The isolation performances, i.e. natural period, damping, and rocking-suppression, have already been evaluated by the technical feasibility study and performance tests on a system which consists of down-sized devices on the shaking table, but in the seismic simulation on the real size building with this system, high hydraulic pressure was generated by rocking-suppression device under an extremely large seismic motion. In this paper, it is reported the frictional characteristics on high hydraulic pressure condition from the experiments on the 1/2 size of real device. To improve the damping performance of rocking-suppression, the orifice was added to the cylinder. At first the linear seismic simulation model of the real size system was constructed and damping coefficient was optimized by using that linear model. Finally, the detailed nonlinear simulation model was constructed, and time history analysis under simultaneous horizontal and vertical seismic motion was carried out, and the damping performance of rocking-suppression device was verified. (author)

282

OPERATIONAL FAULT DIAGNOSIS IN INDUSTRIAL HYDRAULIC SYSTEMS THROUGH MODELING THE INTERNAL LEAKAGE OF ITS COMPONENTS  

Directory of Open Access Journals (Sweden)

Full Text Available In this study, a model of a high pressure hydraulic system was developed using the bond graph method to investigate the effect of the internal leakage of its main components (pump, cylinder and 4/2 way valve on the operational characteristics of the system under various loads. All the main aspects of the hydraulic circuit (like the internal leakages, the compressibility of the fluid, the hydraulic pressure drop, the inertia of moving masses and the friction of the spool were taken into consideration. The results of this modeling were compared with the experimental data taken from the literature and from an actual test platform installed in the laboratory. Modeling and experimental data curves correlate very well in form, magnitude and response times for all the systemâ??s main parameters. This proves that the present method can be used to accurately model the response and operation of hydraulic systems and can thus be used for operational fault diagnosis in many cases, especially in simulating fault scenarios when the defective component is not obvious. This is very important in industrial production systems where unpredictable shutdowns of the hydraulic machinery have a considerable negative economic impact on cost.

P. Athanasatos

2013-01-01

283

Research and development on the hydraulic design system of the guide vanes of multistage centrifugal pumps  

Science.gov (United States)

To improve the hydraulic design accuracy and efficiency of the guide vanes of the multistage centrifugal pumps, four different-structured guide vanes are investigated, and the design processes of those systems are established. The secondary development platforms of the ObjectArx2000 and the UG/NX OPEN are utilized to develop the hydraulic design systems of the guide vanes. The error triangle method is adopted to calculate the coordinates of the vanes, the profiles of the vanes are constructed by Bezier curves, and then the curves of the flow areas along the flow-path are calculated. Two-dimensional and three-dimensional hydraulic models can be developed by this system.

Zhang, Q. H.; Xu, Y.; Shi, W. D.; Lu, W. G.

2012-11-01

284

Research and development on the hydraulic design system of the guide vanes of multistage centrifugal pumps  

International Nuclear Information System (INIS)

To improve the hydraulic design accuracy and efficiency of the guide vanes of the multistage centrifugal pumps, four different-structured guide vanes are investigated, and the design processes of those systems are established. The secondary development platforms of the ObjectArx2000 and the UG/NX OPEN are utilized to develop the hydraulic design systems of the guide vanes. The error triangle method is adopted to calculate the coordinates of the vanes, the profiles of the vanes are constructed by Bezier curves, and then the curves of the flow areas along the flow-path are calculated. Two-dimensional and three-dimensional hydraulic models can be developed by this system.

285

Control of hydraulic pressure cracking on multiphase metallogenesis of vein shape granite-type uranium deposit in Miaoershan orefield  

International Nuclear Information System (INIS)

Morphologies and intertexture of ore veins in vein shape granite-type uranium deposits in Miaoershan ore field in north of Guangxi are studied in detail through using the hydraulic pressure cracking theory and various kinds of testing technique. It is known that the pressure on ore fluid is larger than that of wall rock, and the ore veins are formed by hydraulic pressure cracking. Based on the above discussion, the control of hydraulic pressure cracking on the multiphase metallogenesis of vein shape granite-type uranium deposits is discussed. (author)

286

A development method for the thermal hydraulic transient analysis of parallel channel system  

International Nuclear Information System (INIS)

Parallel channel system is very typical in nuclear power plant, such as in the core and the steam generator. In this paper the author developed one model and a set of codes for the thermal hydraulic transient analysis of a core parallel channel system in QinShan II nuclear power plant. The basic model was built by Clausse and Lahey (1990) and developed by Lee and Pan (1999). In the original model the channel is divided into three parts: entrance section, heater section and riser section. The integral method is used to calculate the pressure of each section. It can reflect the whole characteristics of such system except the local parameters. And the nonuniform heating is very hard to be considered in this model. And the code based on this model is very hard to be coupled with reactor physics code in the future. Hence, the control volume concept is introduced to overcome these weaknesses. The channel can be divided into sufficient control volumes to describe the details. A development model is built based on this concept. Many classical flow and heat transfer correlations and models are included. The Gear method is chosen as the solving implement of the differential equations. Then a code is compiled. And then the transient characteristics are obtained under single and two-phase conditions. The transients of blocking, reactivity insertion and loss of flow are investigated based on imaginary data. At last a coupled method is conceived. (author)

287

Optimal control for a parallel hybrid hydraulic excavator using particle swarm optimization.  

Science.gov (United States)

Optimal control using particle swarm optimization (PSO) is put forward in a parallel hybrid hydraulic excavator (PHHE). A power-train mathematical model of PHHE is illustrated along with the analysis of components' parameters. Then, the optimal control problem is addressed, and PSO algorithm is introduced to deal with this nonlinear optimal problem which contains lots of inequality/equality constraints. Then, the comparisons between the optimal control and rule-based one are made, and the results show that hybrids with the optimal control would increase fuel economy. Although PSO algorithm is off-line optimization, still it would bring performance benchmark for PHHE and also help have a deep insight into hybrid excavators. PMID:23818832

Wang, Dong-yun; Guan, Chen

2013-01-01

288

Comparison of System Identification Techniques for the Hydraulic Manipulator Test Bed (HMTB)  

Science.gov (United States)

In this thesis linear, dynamic, multivariable state-space models for three joints of the ground-based Hydraulic Manipulator Test Bed (HMTB) are identified. HMTB, housed at the NASA Langley Research Center, is a ground-based version of the Dexterous Orbital Servicing System (DOSS), a representative space station manipulator. The dynamic models of the HMTB manipulator will first be estimated by applying nonparametric identification methods to determine each joint's response characteristics using various input excitations. These excitations include sum of sinusoids, pseudorandom binary sequences (PRBS), bipolar ramping pulses, and chirp input signals. Next, two different parametric system identification techniques will be applied to identify the best dynamical description of the joints. The manipulator is localized about a representative space station orbital replacement unit (ORU) task allowing the use of linear system identification methods. Comparisons, observations, and results of both parametric system identification techniques are discussed. The thesis concludes by proposing a model reference control system to aid in astronaut ground tests. This approach would allow the identified models to mimic on-orbit dynamic characteristics of the actual flight manipulator thus providing astronauts with realistic on-orbit responses to perform space station tasks in a ground-based environment.

Morris, A. Terry

1996-01-01

289

High speed hydraulically-actuated operating system for an electric circuit breaker  

Science.gov (United States)

This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a breaker-opening piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A dashpotting mechanism operating separately from the hydraulic actuating system is provided, thereby reducing flow restriction interference with breaker opening. 3 figs.

Iman, I.

1983-06-07

290

Fault Diagnosis for Nonlinear Hydraulic-Mechanical Drilling Pipe Handling System  

DEFF Research Database (Denmark)

Leakage and increased friction are common faults in hydraulic cylinders that can have serious consequences if they are not detected at early stage. In this paper, the design of a fault detector for a nonlinear hydraulic mechanical system is presented. By considering the system in steady state, two residual signals are generated and analysed with a composite hypothesis test which accommodates for unknown parameters. The resulting detector is able to detect abrupt changes in leakage or friction given the noisy pressure and position measurements. Test rig measurements validate the properties of residuals and high fidelity simulation and experimental results demonstrate the performance and feasibility of the proposed method.

Blanke, Mogens

2011-01-01

291

Cluster-based representation of hydraulic systems. [stable (closed valve) and unstable (open valve) states  

Science.gov (United States)

The authors present a technique for structural abstraction applicable to the domain of pressurized hydraulic systems. Valves, when closed, functionally isolate clusters of components; when opened, neighboring clusters are merged. A cluster can only be in the one of two qualitative states-stable, where pressures are equal throughout and no flow occurs, or unstable, where flow from high-pressure source(s) to low-pressure sink(s) occurs. Reasoning in terms of clusters is shown to facilitate the generation and explanation of plans for operating and troubleshooting hydraulic systems.

Farley, Arthur M.

1988-01-01

292

Ecohydrological controls on soil moisture and hydraulic conductivity within a pinyon-juniper woodland  

Science.gov (United States)

The impact of pinyon-juniper woodland encroachment on rangeland ecosystems is often associated with a reduction of streamflow and recharge and an increase in soil erosion. The objective of this study is to investigate vegetational control on seasonal soil hydrologic properties along a 15-m transect in pinyon-juniper woodland with biocrust. We demonstrate that the juniper tree controls soil water content (SWC) patterns directly under the canopy via interception, and beyond the canopy via shading in a preferred orientation, opposite to the prevailing wind direction. The juniper also controls the SWC and unsaturated hydraulic conductivity measured close to water saturation (K(h)) under the canopy by the creation of soil water repellency due to needle drop. We use this information to refine the hydrologic functional unit (HFU) concept into three interacting hydrologic units: canopy patches, intercanopy patches, and a transitional unit formed by intercanopy patches in the rain shadow of the juniper tree. Spatial autoregressive state-space models show the close relationship between K(h) close to soil water saturation and SWC at medium and low levels, integrating a number of influences on hydraulic conductivity. Copyright 2007 by the American Geophysical Union.

Lebron, I.; Madsen, M.D.; Chandler, D.G.; Robinson, D.A.; Wendroth, O.; Belnap, J.

2007-01-01

293

Investigations into the use of water glycol as the hydraulic fluid in a servo system  

International Nuclear Information System (INIS)

The effects of water glycol on the performance of a hydraulic system and on the life of the system components have been investigated and a guide to the design of systems using water glycol is given. The dynamic performance of the system using water-glycol was compared with that using mineral oil, then the system was endurance tested to determine its service life. (author)

294

Water hydraulics in ITER divertor maintenance  

International Nuclear Information System (INIS)

When operating in limited space and with high loads, which is typical for ITER applications, water hydraulics has several advantages compared to other means of power transmission. As a novel technology, water hydraulics includes still some limiting properties, so special solutions are necessary when dealing with systems requiring accurate control. In this paper water hydraulic solution for divertor cassette plasma facing element refurbishment operation is explained. (authors)

295

Interannual to multidecadal variability and predictability of North Atlantic circulation in a coupled earth system model with parametrized hydraulics  

Science.gov (United States)

Several 1000 yr runs of the University of Victoria Earth System Climate Model (UVic ESCM) with a hydraulically controlled overflow in the Denmark Strait are used to analyse the effects of NAO-like variations of the wind stress localized in the subpolar North Atlantic. The focus is laid on improving the representation of the Atlantic meridional overturning circulation (AMOC), the sea surface temperatures in the Nordic Seas and the sea ice coverage without increasing the resolution of the global model. We show that by implementing hydraulic control in the Denmark Strait Overflow the AMOC can be enhanced at depths between 1000 and 3000m by up to 7 Sverdrup (Sv) towards more realistic values. The stability of the Deep Western Boundary Current is considerably enhanced. The expansion of sea ice into the Nordic Seas in the standard run is pushed back from about 65°N to 75°N when hydraulic parametrization is switched on. In this case sea ice variations at 75°N and Northern Europe air temperatures exhibit a lag of 9 yr to variations in the wind stress curl.

Köller, M.; Käse, R. H.; Herrmann, P.

2010-08-01

296

Brandrisker och Skydd i Distributions- System foer Hydraul- och Skaervaetskor. BRANDFORSK Projekt 744-961 (Fire Hazards and Fire Protection of Distributing Systems for Hydraulic Oil and Cutting Oil).  

Science.gov (United States)

In many large scale industrial fires with large losses, hydraulic systems, cutting systems, power and cooling fluids are the primary cause. The dangers present in these systems are large pressure, the fluid itself and presence of ignition sources such as ...

M. Milovancevic, M. Arvidson

1997-01-01

297

Teaching Thermal Hydraulics and Numerical Methods: An Introductory Control Volume Primer  

International Nuclear Information System (INIS)

A graduate level course for Thermal Hydraulics (T/H) was taught through Idaho State University in the spring of 2004. A numerical approach was taken for the content of this course since the students were employed at the Idaho National Laboratory and had been users of T/H codes. The majority of the students had expressed an interest in learning about the Courant Limit, mass error, semi-implicit and implicit numerical integration schemes in the context of a computer code. Since no introductory text was found the author developed notes taught from his own research and courses taught for Westinghouse on the subject. The course started with a primer on control volume methods and the construction of a Homogeneous Equilibrium Model (HEM) (T/H) code. The primer was valuable for giving the students the basics behind such codes and their evolution to more complex codes for Thermal Hydraulics and Computational Fluid Dynamics (CFD). The course covered additional material including the Finite Element Method and non-equilibrium (T/H). The control volume primer and the construction of a three-equation (mass, momentum and energy) HEM code are the subject of this paper . The Fortran version of the code covered in this paper is elementary compared to its descendants. The steam tables used are less accurate than the available commercial version written in C Coupled to a Graphical User Interface (GUI). The Fortran version and input files can be downloaded at www.microfusionlab.comownloaded at www.microfusionlab.com

298

Effect of Propellant Feed System Coupling and Hydraulic Parameters on Analysis of Chugging  

Science.gov (United States)

A digital distributed parameter model was used to study the effects of propellant-feed- system coupling and various hydraulic parameters on the analytical prediction of chugging instabilities. Coupling between the combustion chamber and feed system was controlled by varying the compliance of the injector-dome region. The coupling with the feed system above the pump was varied by changing the amount of cavitation compliance at the pump inlet. The stability limits and chugging frequencies proved to be strongly dependent on the degree of feed-system coupling. The maximum stability condition occurred with intermediate coupling. Under conditions of a high degree of feed-system-combustor coupling, the stability limits and chugging frequencies were primarily dependent on the feed-system characteristics; the responses were characterized by beating patterns. For the system analyzed, the pump suction line had little effect on the stability limits or chugging frequencies. Beating, present under the condition of near zero injector -dome compliance, was eliminated when the suction line was decoupled by employing a sufficiently high value of pump-inlet compliance. Under conditions of maximum feed-system coupling, the magnitude and distribution of line losses in the discharge line had a significant effect on the stability limits but had negligible effect on the chugging frequency and beating characteristics. Also, the length of the discharge line greatly affected the stability limits, chugging frequency, and beating characteristics. The length of the suction line, however, had little effect on the stability limits and chugging frequency but did influence the beating pattern. A resistive-shunt device attached to the pump discharge line to suppress chugging was investigated. The analysis showed that the device was effective under conditions of high feed-system coupling.

Wood, Don J.; Dorsch, Robert G.

1967-01-01

299

Comparison for the interfacial and wall friction models in thermal-hydraulic system analysis codes  

Energy Technology Data Exchange (ETDEWEB)

The average equations employed in the current thermal hydraulic analysis codes need to be closed with the appropriate models and correlations to specify the interphase phenomena along with fluid/structure interactions. This includes both thermal and mechanical interactions. Among the closure laws, an interfacial and wall frictions, which are included in the momentum equations, not only affect pressure drops along the fluid flow, but also have great effects for the numerical stability of the codes. In this study, the interfacial and wall frictions are reviewed for the commonly applied thermal-hydraulic system analysis codes, i.e. RELAP5-3D, MARS-3D, TRAC-M, and CATHARE.

Hwang, Moon Kyu; Park, Jee Won; Chung, Bub Dong; Kim, Soo Hyung; Kim, See Dal

2007-07-15

300

Hydraulic and thermal performance assessment of cooling water systems at E.I. Hatch Nuclear Plant  

International Nuclear Information System (INIS)

eloped and used successfully for flow balancing at the Limerick Generating Station during initial plant startup. The BALANCE hydraulic network model provides an accurate analytical representation of the Hatch Plant Service Water System on each unit. A summary of program capabilities and modeling assumptions, as well as observations which have been made by comparison of program predictions with test results, is presented here

 
 
 
 
301

Interconnection of acoustic and erosion features of cavitation processes in hydraulic devices and systems  

International Nuclear Information System (INIS)

Interconnection of acoustic and erosion features of cavitation processes in hydraulic devices and systems is considered and a possibility of determining threshold conditions for cavitation transfer from erosion-free regime to regime accompanied by intense structural material erosion, is analysed. Description of an experimental plant and its equipment is given

302

Aircraft Fuel, Hydraulic and Pneumatic Systems (Course Outlines), Aviation Mechanics 3 (Air Frame): 9067.01.  

Science.gov (United States)

This document presents an outline for a 135-hour course designed to familiarize the student with the operation, inspection, and repair of aircraft fuel, hydraulic, and pneumatic systems. It is designed to help the trainee master the knowledge and skills necessary to become an aviation airframe mechanic. The aviation airframe maintenance technician…

Dade County Public Schools, Miami, FL.

303

Evaluation of elastomers as gasket materials in pneumatic and hydraulic systems  

Science.gov (United States)

In the search for superior materials from which to make gaskets for pneumatic and hydraulic systems, promising materials were selected and tested. The testing was conducted in two phases. Those materials that passed the tests of Phase 1 were tested in Phase 2, and categorized in the order of preference.

Bright, C. W.; Lockhart, B. J.

1972-01-01

304

O-ring tube fittings form leakproof seal in hydraulic systems  

Science.gov (United States)

Leakproof fittings for hydraulic systems are designed to be welded to the ends of the tubing to be joined and mated to form a seal with one o-ring at the joint. Since the fittings are coupled at only one joint, they tend to be more reliable than standard fittings coupled at two joints.

1966-01-01

305

Engine with hydraulic fuel injection and ABS circuit using a single high pressure pump  

Science.gov (United States)

An engine system comprises a hydraulically actuated fuel injection system and an ABS circuit connected via a fluid flow passage that provides hydraulic fluid to both the fuel injection system and to the ABS circuit. The hydraulically actuated system includes a high pressure pump. The fluid control passage is in fluid communication with an outlet from the high pressure pump.

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

2001-01-01

306

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2011-02-01

307

Oil management for wind power system hydraulics; Oelmanagement fuer die Hydraulik von Windkraftanlagen  

Energy Technology Data Exchange (ETDEWEB)

More than 80 percent of all cases of damage in hydraulic systems are caused by impurities in the system, i.e. solid particles, bound or free water and air, and their compounds. (orig.) [German] Es ist allgemein bekannt und akzeptiert: Ueber 80% aller Schaeden in der Hydraulik werden durch Verunreinigung im System verursacht. Diese Verunreinigungen bestehen aus Festpartikeln, gebundenes und oder freies Wasser und Luft und deren Verbindungen. (orig.)

Gadringer, J. [Koppen Lethem, Waddingsxveen (Netherlands)

2004-07-01

308

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

International Nuclear Information System (INIS)

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

309

Electric vehicle regenerative antiskid braking and traction control system  

Science.gov (United States)

An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydrualic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control.

Cikanek, Susan R. (Wixom, MI)

1995-01-01

310

RE-1000 free-piston Stirling engine hydraulic output system description  

Science.gov (United States)

The NASA Lewis Research Center was involved in free-piston Stirling engine research since 1976. Most of the work performed in-house was related to characterization of the RE-1000 engine. The data collected from the RE-1000 tests were intended to provide a data base for the validation of Stirling cycle simulations. The RE-1000 was originally build with a dashpot load system which did not convert the output of the engine into useful power, but was merely used as a load for the engine to work against during testing. As part of the interagency program between NASA Lewis and the Oak Ridge National Laboratory, (ORNL), the RE-1000 was converted into a configuration that produces useable hydraulic power. A goal of the hydraulic output conversion effort was to retain the same thermodynamic cycle that existed with the dashpot loaded engine. It was required that the design must provide a hermetic seal between the hydraulic fluid and the working gas of the engine. The design was completed and the hardware was fabricated. The RE-1000 was modified in 1985 to the hydraulic output configuration. The early part of the RE-1000 hydraulic output program consisted of modifying hardware and software to allow the engine to run at steady-state conditions. A complete description of the engine is presented in sufficient detail so that the device can be simulated on a computer. Tables are presented showing the masses of the oscillating components and key dimensions needed for modeling purposes. Graphs are used to indicate the spring rate of the diaphragms used to separate the helium of the working and bounce space from the hydraulic fluid.

Schreiber, Jeffrey G.; Geng, Steven M.

1987-01-01

311

Hydraulic transient analysis for PWR auxiliary feedwater system  

International Nuclear Information System (INIS)

esults of the system revealed the AFWP suction pressure will drop close to the fluid vapor pressure under certain mode of the system operation, that caused the damage of the two(2) motor driven AFWPs. (author)

312

BSF control system  

International Nuclear Information System (INIS)

The booster synchrotron utilization facility (BSF) is a facility which utilizes the four fifths of available beam pulses from the KEK booster synchrotron. The BSF control system includes the beam line control, interactions with the PS central control room and the experimental facilities, and the access control system. A brief description of the various components in the control system is given. (author)

313

Design, Optimization and Analysis of Hydraulic Soft Yaw System for 5 MW Wind Turbine  

DEFF Research Database (Denmark)

As wind turbines increase in size and the demands for lifetime also increases, new methods of load reduction needs to be examined. One method is to make the yaw system of the turbine soft/flexible and hence dampen the loads to the system, which is the focus of the current paper. The paper first presents work previous done on this subject with focus on hydraulic yaw systems. 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. Results show that a significant reduction in fatigue and extreme loads to the yaw system and rotor shaft are possible, 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. The duty cycles, based on the extrapolated loads, show that it is possible to construct a hydraulic soft yaw system, which is able to reduce theloads on the wind turbine significantly.

Stubkier, SŘren; Pedersen, Henrik C.

2011-01-01

314

A Hydraulic Motor-Alternator System for Ocean-Submersible Vehicles  

Science.gov (United States)

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.

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

2012-01-01

315

Handbook of hydraulic fluid technology  

CERN Document Server

""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

Totten, George E

2011-01-01

316

RAMONA-3B/MINET composite representation of BWR thermal-hydraulic systems  

International Nuclear Information System (INIS)

The modification and interfacing of two computer codes, RAMONA-3B and MINET, for the thermal hydraulic transient analysis of a Boiling Water Reactor nuclear steam supply system, is described. The RAMONA-3B code provides for multi-channel thermal hydraulics and three-dimensional (or one-dimensional) neutron kinetics analysis of a boiling water reactor core. The RAMONA-3B system representation terminates at the end of the steam line and at the junction of the feedwater line at the vessel inlet. By interfacing RAMONA-3B with MINET, a generic balance-of-plant systems analysis code, a complete BWR systems code with detailed core modeling was obtained. The result is a code of particulate importance to the analysis of transients such as ATWS

317

Parameter Design for the Energy-Regeneration System of Series Hydraulic-Hybrid Bus  

Directory of Open Access Journals (Sweden)

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.  

SONG Yunpu

2012-10-01

318

Hydraulic modeline of pump systems in water distribution networks  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Water distribution networks provide water supply to consumers. Pumping system adds mechanical work, thus providing sufficient amount of energy for water distribution throughout network. Pump's mechanical work is made by consuming electrical power. Because consumption of electricity and costs of consumed energy are high improvements made on operation of pumping system can lead to non negligible savings. When optimising pump system's operation different factors have to be taken into account (hy...

Robic?, Gregor

2013-01-01

319

Control system design method  

Science.gov (United States)

A control system design method and concomitant control system comprising representing a physical apparatus to be controlled as a Hamiltonian system, determining elements of the Hamiltonian system representation which are power generators, power dissipators, and power storage devices, analyzing stability and performance of the Hamiltonian system based on the results of the determining step and determining necessary and sufficient conditions for stability of the Hamiltonian system, creating a stable control system based on the results of the analyzing step, and employing the resulting control system to control the physical apparatus.

Wilson, David G. (Tijeras, NM); Robinett, III, Rush D. (Tijeras, NM)

2012-02-21

320

Improvements to the measurement of electrically controlled hydraulic pumps' flow/pressure characteristics  

International Nuclear Information System (INIS)

To increase the measurement accuracy, and also to automate the measurement operation, we modify the electrically controlled hydraulic pumps' (ECHPs') flow/pressure performance characteristic description and improve the test method in existent standards. According to ECHPs' working principle, we divide ECHPs' operation into two models: constant flow operating mode (CFOM) and constant pressure operating mode (CPOM). A direct drive servo-proportional control valve (DDV) is used to load the test pump. In the CFOM, we change the pressure load at a constant rate by driving the DDV's displacement with nonlinear feedback and a proportional–integral (PI) controller. In the CPOM, we take advantage of the DDV's inherent linearity between its input signal and output flow, and change the flow load at a constant rate by using open-loop spool displacement control. A mathematic model is built for the derivation of a stable condition and the analysis of steady-state pressure tracking error. The theoretical analysis shows that the feedback linearization and PI controller with negative proportional and integral gains are able to track a slope pressure load command with a desired rate. The test results also show that the mathematical model is valid and the proposed method can improve the measurement accuracy remarkably

 
 
 
 
321

Dynamic Model of a Hydraulic Servo System for a Manipulator Robot  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this master thesis, a mathematical model of a hydraulic servo system for a manipulator robot is completed by using several different methodologies. The models proposed are particularly tuned for the DeLaval VMS robotic arm. The parameter identification of the robotic arm is accomplished by dividing the model into several subsystems and investigating each system separately by using catalogue data, experimental data and construction drawings. Furthermore, the assumptions are proposed based o...

Efe, Yalcin

2014-01-01

322

Modeling with AFT Fathom of hydraulic systems. Application to the Asco nuclear power station  

International Nuclear Information System (INIS)

This paper gives an overview of the simulation of hydraulic systems with program AFT Fathom, describing practical applications carried out in NPP Asco. The results of the simulation are used to determine the behavior certain systems under hardly reproducible scenarios in reality, such as emergency and accident situations. In this sense, are presented real-life examples carried out in C. N. disgust and shown how the simulation puts in the hands of engineers valuable information for decision-making.

323

Advanced model structures applied to system identification of a servo- hydraulic test rig  

Directory of Open Access Journals (Sweden)

Full Text Available Purpose: This paper deals with a method for the parametric system identification of a nonlinear system to obtain its parametric representation using a linear transfer function. Such representation is applicable in off-line profile correction methods minimizing the error between a reference input signal and a signal performed by the test rig. In turn, a test signal can be perfectly tracked by a servo-hydraulic test rig. This is the requirement in massive production where short test sequences are repeated to validate the products.Design/methodology/approach: A numerical and experimental case studies are presented in the paper. The numerical study presents a system identification process of a nonlinear system consisting of a linear transfer function and a nonlinear output component, being a static function. The experimental study presents a system identification process of a nonlinear system which is a servo-hydraulic test rig. The simulation data has been used to illustrate the feasibility study of the proposed approach, while the experimental data have been used to validate advanced model structures under operational conditions.Findings: The advanced model structures confirmed their better performance by means of the model fit in the time domain.Research limitations/implications: The method applies to analysis of such mechanical and hydraulic systems for which measurements are corrupted by residual harmonic disturbances resulting from system nonlinearities.Practical implications: The advanced model structures are intended to be used as inverse models in off-line signal profile correction.Originality/value: The results state the foundation for the off-line parametric error cancellation method which aims in improving tracking of load signals on servo-hydraulic test rigs.

P. Czop

2010-07-01

324

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

Science.gov (United States)

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

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

2001-06-22

325

FOREWORD: The XXV IAHR Symposium on Hydraulic Machinery and Systems marks half a century tradition  

Science.gov (United States)

IAHR75_logoUPT90_logoARFT_logo International Association of Hydro-Environment Engineering and Research'Politehnica' University of TimisoaraRomanian Academy - Timisoara Branch The 25th edition of the IAHR Symposium on Hydraulic Machinery and Systems, held in Timisoara, Romania, 20-24 September 2010, jointly organized by the 'Politehnica' University of Timisoara and the Romanian Academy - Timisoara Branch, marks a half century tradition of these prestigious symposia. However, it is the first time that Romania hosts such a symposium, and for good reasons. The Romanian electrical power system has a total of 20,630 MW installed power, out of which 6,422 MW in hydropower plants. The energy produced in hydropower facilities was in 2008 of 17,105 GWh from a total of 64,772 GWh electrical energy production. Moreover, for the period 2009-2015, new hydropower capacities are going to be developed, with a total of 2,157 MW installed power and an estimated 5,770 GWh/year energy production. Within the same period of time, the refurbishment, modernization and repair programs will increase the actual hydropower production with an estimated 349 GWh/year. The 'Politehnica' University of Timisoara is proud to host the 25th IAHR Symposium on Hydraulic Machinery and Systems, in the year of its 90th anniversary. The 'Politehnica' University of Timisoara is one of the largest and most well-known technical universities from Central and Eastern Europe. It was founded in 1920, a short time after the union into one state of all the Romanian territories, following the end of the First World War, in order to respond to the need engineers felt by the Romanian society at that time, within the economical development framework. During its 90 years of existence, 'Politehnica' University of Timisoara educated over 100,000 engineers, greatly appreciated both in Romania and abroad, for their competence and seriousness. King Ferdinand I of Romania said while visiting the recently established 'Politehnica' of Timisoara in 1923 'It is not the walls that make a school, but the spirit living inside'. A particular trademark of the 'Politehnica' of Timisoara was the continuous effort to answer industrial problems by training the students not only on theoretical aspects but also in design and manufacturing, as well as in laboratory works. Developing modern laboratories, where students can observe and understand first hand the engineering applications along the years a priority for Timisoara 'Politehnica' University. The School of Hydraulic Machinery within the 'Politehnica' University of Timisoara was established in early 1930 by Professor Aurel Barglazan (1905-1960), and further developed by Professor Ioan Anton (born 1924), both members of the Romanian Academy. The Laboratory of Hydraulic Machines from Timisoara (LMHT) started back in 1928 in a small hut, with a test rig for Francis and Kaplan turbines manufactured by J M Voith. LMHT was continuously developed and was officially recognized in 1959 as being one of the leading research and developing laboratories in Romania. It was the foundation of the Romanian efforts of designing and manufacturing hydraulic turbines starting in 1960 at the Resita Machine Building Factory. Under the leadership of Professor Ioan Anton, the Timisoara School in Hydraulic Machinery has focused the basic and development research activities on the following main topics: (i) Turbine Hydrodynamics, (ii) Hydrofoil Cascade Hydrodynamics, (iii) Cavitation in Hydraulic Machines and Equipments, (iv) Scale-up Effects in Hydraulic Machines. With the establishment in the year 2000 of the National Center for Engineering of Systems with Complex Fluids, within the 'Politehnica' University of Timisoara, the research in turbomachinery hydrodynamics and cavitation included high performance computing for flows in hydraulic machines, as well as the development of novel technologies to mitigate the self-induced flow instabilities in hydraulic turbines operated far from the best efficiency regime. The traditional partnership with the Romanian Academy - Tim

Susan-Resiga, Romeo

2010-05-01

326

Thermal-Hydraulic System Codes in Nulcear Reactor Safety and Qualification Procedures  

Directory of Open Access Journals (Sweden)

Full Text Available In the last four decades, large efforts have been undertaken to provide reliable thermal-hydraulic system codes for the analyses of transients and accidents in nuclear power plants. Whereas the first system codes, developed at the beginning of the 1970s, utilized the homogenous equilibrium model with three balance equations to describe the two-phase flow, nowadays the more advanced system codes are based on the so-called “two-fluid model” with separation of the water and vapor phases, resulting in systems with at least six balance equations. The wide experimental campaign, constituted by the integral and separate effect tests, conducted under the umbrella of the OECD/CSNI was at the basis of the development and validation of the thermal-hydraulic system codes by which they have reached the present high degree of maturity. However, notwithstanding the huge amounts of financial and human resources invested, the results predicted by the code are still affected by errors whose origins can be attributed to several reasons as model deficiencies, approximations in the numerical solution, nodalization effects, and imperfect knowledge of boundary and initial conditions. In this context, the existence of qualified procedures for a consistent application of qualified thermal-hydraulic system code is necessary and implies the drawing up of specific criteria through which the code-user, the nodalization, and finally the transient results are qualified.

Alessandro Petruzzi

2008-01-01

327

Development and verification of a thermo-hydraulic simulation code for systems transient in 'Monju' (COPD code)  

International Nuclear Information System (INIS)

Large system simulation codes are needed for design and safety analysis. A thermal-hydraulic simulation code for systems transient in ''Monju'' (COPD code) was developed and verified with experimental data from an experimental LMFBR ''Joyo'', 50 MWt steam generator test facility and scaled test sections of reactor vessel plenum. This paper summarizes numerical models of this code and their verifications with experimental data. Especially, a simplified analytical model to predict the transient behavior in a reactor vessel plenum is presented in detail, since this behavior has an important effect that must be taken into account in a plant thermal transient, while the reactor is tripped. The COPD is applied to design and safety analysis in ''Monju'' as follows ; (1) Safety analysis with regard to core cooling in anticipated incidents. (2) Plant thermo-hydraulic analysis for setting the design condition in thermal stress analysis and evaluation of components and pipings. (3) Control performance analysis on plant operation for design and evaluation of plant control system. Each of the above analyses requires different predictions of plant response to be analyzed. Therefore, appropriate models and input data are used in the design and evaluation according to the purpose of the analysis. This code was developed and verified under a contract with PNC. (author)

328

High Resolution Hydraulic Profiling and Groundwater Sampling using FLUTe™ System in a Fractured Limestone Setting  

DEFF Research Database (Denmark)

Characterization of the contaminant source zone architecture and the hydraulics is essential to develop accurate site specific conceptual models, delineate and quantify contaminant mass, perform risk as-sessment, and select and design remediation alternatives. This characterization is particularly challeng-ing in deposit types as fractured limestone. The activities of a bulk distribution facility for perchloroe-thene (PCE) and trichloroethene (TCE) at the Naverland site near Copenhagen, Denmark, has resulted in PCE and TCE DNAPL impacts to a fractured clay till and an underlying fractured limestone aqui-fer/bedrock. A wide range of innovative and current site investigative tools for direct and indirect docu-mentation and/or evaluation of dense non-aqueous phase liquid (DNAPL) presence were combined in a multiple lines of evidence approach. One scope of the investigations was to evaluate innovative investi-gation methods for characterization of the source zone hydrogeology and contamination, including FLUTe system hydraulic profiling and Water-FLUTe multilevel groundwater sampling, in fractured bryo-zoan limestone bedrock. High resolution hydraulic profiling was conducted in three cored boreholes, placed within a 970 ft2 (~90 m2) area, and Water-FLUTes were installed with 12-13 sampling screens in each borehole. Hydraulic profilling by FLUTe liner system provided information with highere discretization than other traditionel methods, and supported the individual design of Water-FLUTes for multilevel groundwater monitoring, sampling (under two flow conditions) and analysis. Coring for discrete subsampling was a challenge in the limestone, due to core-loss and potential DNAPL loss caused by high drilling water pressure. Hence, the water-FLUTe data proved to be an essential link in the source zone characterization. The results from the high resolution hydraulic profiling and from the Water-FLUTe multilevel sampling will be pre-sented as well as the experiences obtained.

Janniche, Gry Sander; Christensen, Anders G.

329

Hydraulic Conductivity Estimation Test Impact on Long-Term Acceptance Rate and Soil Absorption System Design  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of this paper was to verify the common methods of hydraulic conductivity estimation for soil assessment in respect to wastewater disposal. The studies were conducted on three types of sandy soils. Hydraulic conductivity was determined using a scale effect-free laboratory method, empirical equations and compared with measurements estimated from a laboratory infiltration column with identified head loss. Based on the hydraulic conductivity values, the long-term acceptance rates (LTAR [1] were calculated. The differences in LTAR values were about one order of magnitude smaller than differences in hydraulic coefficient. The study showed a good convergention of the results obtained from the constant head method (CHM by solving the Glover Equation for medium and coarse sands. In low permeability soil (fine sand, the best result was obtained using CHM-a with a capillary rise consideration (a is a factor included in the flow in the unsaturated and saturated zones calculated from a capillary rise. From a practical point of view the relatively small value of LTAR underestimation (20%-for constant head method is responsible for the extended surface area of the system and provides a security margin (the avoidance of clogging risk. The use of the falling head method, based on the Van Hoorn equation, can be said to be highly overestimated. For medium and coarse sandy soils the underestimation of LTAR calculated and based on CHM test determination is 14%–18%. The total cost of soil absorption system (SAS designed-based on CHM in comparison to that designed-based on real hydraulic conductivity value in Poland is only about 7%–9% higher.

Jakub Nie?

2014-09-01

330

Analytical and experimental investigation of chlorine decay in water supply systems under unsteady hydraulic conditions  

DEFF Research Database (Denmark)

This paper investigates the impact of the dynamic hydraulic conditions on the kinetics of chlorine decay in water supply systems. A simulation framework has been developed for the scale-adaptive hydraulic and chlorine decay modelling under steady- and unsteady-state flows. An unsteady decay coefficient is defined which depends upon the absolute value of shear stress and the rate of change of shear stress for quasi-unsteady and unsteady-state flows. By coupling novel instrumentation technologies for continuous hydraulic monitoring and water quality sensors for in-pipe water quality sensing a pioneering experimental and analytical investigation was carried out in a water transmission main. The results were used to model monochloramine decay and these demonstrate that the dynamic hydraulic conditions have a significant impact on water quality deterioration. The spatial and temporal resolution of experimental data provides new insights for the near real-time modelling and management of water quality as well as highlighting the uncertainty and challenges of accurately modelling the loss of disinfectant in water supply networks.

Aisopou, Angeliki; Stoianov, Ivan

2013-01-01

331

Improvement of multi-dimensional realistic thermal-hydraulic system analysis code, MARS 1.3  

Energy Technology Data Exchange (ETDEWEB)

The MARS (Multi-dimensional Analysis of Reactor Safety) code is a multi-dimensional, best-estimate thermal-hydraulic system analysis code. This report describes the new features that have been improved in the MARS 1.3 code since the release of MARS 1.3 in July 1998. The new features include: - implementation of point kinetics model into the 3D module - unification of the heat structure model - extension of the control function to the 3D module variables - improvement of the 3D module input check function. Each of the items has been implemented in the developmental version of the MARS 1.3.1 code and, then, independently verified and assessed. The effectiveness of the new features is well verified and it is shown that these improvements greatly extend the code capability and enhance the user friendliness. Relevant input data changes are also described. In addition to the improvements, this report briefly summarizes the future code developmental activities that are being carried out or planned, such as coupling of MARS 1.3 with the containment code CONTEMPT and the three-dimensional reactor kinetics code MASTER 2.0. (author). 8 refs.

Lee, Won Jae; Chung, Bub Dong; Jeong, Jae Jun; Ha, Kwi Seok

1998-09-01

332

Improvement of multi-dimensional realistic thermal-hydraulic system analysis code, MARS 1.3  

International Nuclear Information System (INIS)

The MARS (Multi-dimensional Analysis of Reactor Safety) code is a multi-dimensional, best-estimate thermal-hydraulic system analysis code. This report describes the new features that have been improved in the MARS 1.3 code since the release of MARS 1.3 in July 1998. The new features include: - implementation of point kinetics model into the 3D module - unification of the heat structure model - extension of the control function to the 3D module variables - improvement of the 3D module input check function. Each of the items has been implemented in the developmental version of the MARS 1.3.1 code and, then, independently verified and assessed. The effectiveness of the new features is well verified and it is shown that these improvements greatly extend the code capability and enhance the user friendliness. Relevant input data changes are also described. In addition to the improvements, this report briefly summarizes the future code developmental activities that are being carried out or planned, such as coupling of MARS 1.3 with the containment code CONTEMPT and the three-dimensional reactor kinetics code MASTER 2.0. (author). 8 refs

333

Thermal-hydraulics of a steam discharge system  

International Nuclear Information System (INIS)

Physical characteristics of the steam discharge system of PWR, which consists of valves, piping, steam sparger, and steam accommodating tank, have been analyzed and the analysis system has been set up for development of the analysis and design methodology for the system. The work was the results of the final year research in the planned research period of three years. Analysis has been made for the characteristics of rapid transient and steady flow in the piping, bubble behavior and wall pressure oscillation in a large and open tank, steam condensation, thermal mixing performance in a pool, and small and hermetically sealed tank performance. Based on the analysis results, experimental requirements for the development provided. Finally, for the further work in developing KNGR, the implementing approach related to this work has been purposed. 42 figs, 2 tabs, 29 refs. (Author)

334

Staged cost optimization of urban storm drainage systems based on hydraulic performance in a changing environment  

Directory of Open Access Journals (Sweden)

Full Text Available Urban flooding causes large economic losses, property damage and loss of lives. The impact of environmental changes, mainly urbanization and climatic change, leads to increased runoff and peak flows which the drainage system must be able to cope with to reduce potential damage and inconvenience. Allowing for detention storage to compliment the conveyance capacity of the drainage system network is one of the approaches to reduce urban floods. Contemporary practice is to design systems against stationary environmental forcings – including design rainfall, landuse, etc. Due to the rapid change in the climate- and the urban environment, this approach is no longer appropriate, and explicit consideration of gradual changes during the life-time of the drainage system is warranted. In this paper, a staged cost optimization tool based on the hydraulic performance of the drainage system is presented. A one dimensional hydraulic model is used for hydraulic evaluation of the network together with a genetic algorithm based optimization tool to determine optimal intervention timings and responses over the analysis period. The model was applied in a case study area in the city of Porto Alegre, Brazil. It was concluded that considerable financial savings and/or additional level of flood-safety can be achieved by approaching the design problem as a staged plan rather than one-off scheme.

M. Maharjan

2009-04-01

335

Staged cost optimization of urban storm drainage systems based on hydraulic performance in a changing environment  

Directory of Open Access Journals (Sweden)

Full Text Available Urban flooding causes large economic losses, property damage and loss of lives. The impact of environmental changes mainly, the urbanization and the climatic change leads to increased runoff and increased peak flows which the drainage system must be able to cope with to overcome possible damage and inconveniences caused by the induced flooding. Allowing for detention storage to compliment the capacity of the drainage system network is one of the approaches to reduce urban floods. The traditional practice was to design systems against stationary environmental forcings – including design rainfall, landuse, etc. Due to the rapid change in climate-environment, this approach is no longer economically viable and safe, and explicit consideration of changes that gradually take place during the life-time of the drainage system is warranted. In this paper, a staged cost optimization tool based on the hydraulic performance of the drainage system is presented. A one dimensional hydraulic model is used for hydraulic evaluation of the network together with a genetic algorithm based optimization tool to determine optimal intervention timings and amounts throughout the lifespan of the drainage network. The model was applied in a case study area in the city of Porto Alegre, Brazil. It was concluded that considerable financial savings and/or additional level of flood-safety can be achieved by approaching the design problem as a staged plan rather than one-off scheme.

M. Maharjan

2008-06-01

336

Free-piston Stirling hydraulic engine and drive system for automobiles  

Science.gov (United States)

The calculated fuel economy for an automotive free piston Stirling hydraulic engine and drive system using a pneumatic accumulator with the fuel economy of both a conventional 1980 spark ignition engine in an X body class vehicle and the estimated fuel economy of a 1984 spark ignition vehicle system are compared. The results show that the free piston Stirling hydraulic system with a two speed transmission has a combined fuel economy nearly twice that of the 1980 spark ignition engine - 21.5 versus 10.9 km/liter (50.7 versus 25.6 mpg) under comparable conditions. The fuel economy improvement over the 1984 spark ignition engine was 81 percent. The fuel economy sensitivity of the Stirling hydraulic system to system weight, number of transmission shifts, accumulator pressure ratio and maximum pressure, auxiliary power requirements, braking energy recovery, and varying vehicle performance requirements are considered. An important finding is that a multispeed transmission is not required. The penalty for a single speed versus a two speed transmission is about a 12 percent drop in combined fuel economy to 19.0 km/liter (44.7 mpg). This is still a 60 percent improvement in combined fuel economy over the projected 1984 spark ignition vehicle.

Beremand, D. G.; Slaby, J. G.; Nussle, R. C.; Miao, D.

1982-01-01

337

Petri Net Model and Reliability Evaluation for Wind Turbine Hydraulic Variable Pitch Systems  

Directory of Open Access Journals (Sweden)

Full Text Available Based on an analysis of the working principles of the hydraulic variable pitch system of a wind turbine, a novel Petri net model and reliability evaluation method are proposed. First, Petri net theory is adopted to build a model for each discrete state of the operation of the hydraulic pitch system of the wind turbine and at the same time a fault Petri net model is established. Then through qualitative analysis and quantitative calculations based on the fault Petri net, the system reliability indexes are obtained. During the qualitative analysis process, in order to more conveniently find the minimal cut sets of the fault Petri net, a Visual C++ 6.0-based algorithm is compiled and the minimal cut sets are tested correctly with another method. During the quantitative calculation process, the fault probability has been obtained from the equations according to the fault probability of libraries and transitions between different states. Not only does the proposed Petri net describe the structure, function and operation of the hydraulic pitch system with a graphic language, but the fault Petri net model can also clearly express the logical relations among faults. The novel Petri net model offers simple calculations and the prospect of broad applicability and the new reliability evaluation method provides an important reference for the performance evaluation of these systems.

Xiyun Yang

2011-06-01

338

TARN control system  

International Nuclear Information System (INIS)

During the construction of TARN, many kinds of equipments for the accelerator have been developed and many advances in the control system have been made successfully. Main parts of the control system are management of timing control, inter-locking, data logging and interfacing of computer control. Present paper describes the design conception of the TARN control system as well as the details of the construction. Considerations about cabling and standardization of control parts are also presented. (author)

339

Utilization of a hydraulic barrier to control migration of a uranium plume  

Energy Technology Data Exchange (ETDEWEB)

A uranium plume emanating from the U.S. Department of Energy`s Fernald Environmental Management Project (FEMP) in Fernald, Ohio had migrated off site and the leading edge of the plume had already mixed with an organic and inorganic plume emanating from two industries south of the FEMP. A method was needed to prevent the further southern migration of the plume, minimize any impacts to the geometry, concentrations, distribution or flow patterns of the organic and inorganic plumes emanating from the off-site industries, while meeting the ultimate cleanup goals for the FEMP. This paper discusses the use of a hydraulic barrier created to meet these goals by pumping a five well recovery system and the problems associated with the disposition of over 2 million gallons per day of water with low concentrations of uranium.

Brettschneider, D.J.; Simmons, R.A. Jr. [Fernald Environmental Management Project, Cincinnati, OH (United States); Kappa, J.D.; Stover, J.A.

1995-01-25

340

Utilization of a hydraulic barrier to control migration of a uranium plume  

International Nuclear Information System (INIS)

A uranium plume emanating from the U.S. Department of Energy's Fernald Environmental Management Project (FEMP) in Fernald, Ohio had migrated off site and the leading edge of the plume had already mixed with an organic and inorganic plume emanating from two industries south of the FEMP. A method was needed to prevent the further southern migration of the plume, minimize any impacts to the geometry, concentrations, distribution or flow patterns of the organic and inorganic plumes emanating from the off-site industries, while meeting the ultimate cleanup goals for the FEMP. This paper discusses the use of a hydraulic barrier created to meet these goals by pumping a five well recovery system and the problems associated with the disposition of over 2 million gallons per day of water with low concentrations of uranium

 
 
 
 
341

Thermal Hydraulic numerical analysis of Fusion superconducting magnet systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the present scenario, the International Thermonuclear Experimental Reactor (ITER) is in progress and efforts are being made to extend ITER to DEMOnstration Power plant (DEMO) with the purpose to harness the fusion energy for peaceful and constructive purposes. ITER uses the sueperconducting magnet systems for trapping and maneuvering plasma inside the giant tokamak machines. Superconductivity only entails under the critical conditions of temperature, magnetic field and current density. If ...

Kholia, Akshat

2013-01-01

342

Using seismic tomography to characterize fracture systems induced by hydraulic fracturing  

Energy Technology Data Exchange (ETDEWEB)

Microearthquakes induced by hydraulic fracturing have been studied by many investigators to characterize fracture systems created by the fracturing process and to better understand the locations of energy resources in the earth`s subsurface. The pattern of the locations often contains a great deal of information about the fracture system stimulated during the hydraulic fracturing. Seismic tomography has found applications in many areas for characterizing the subsurface of the earth. It is well known that fractures in rock influence both the P and S velocities of the rock. The influence of the fractures is a function of the geometry of the fractures, the apertures and number of fractures, and the presence of fluids in the fractures. In addition, the temporal evolution of the created fracture system can be inferred from the temporal changes in seismic velocity and the pattern of microearthquake locations. Seismic tomography has been used to infer the spatial location of a fracture system in a reservoir that was created by hydraulic fracturing.

Fehler, M.; Rutledge, J.

1995-01-01

343

Beneficial effects on water management of simple hydraulic structures in wetland systems: the Vallevecchia case study, Italy.  

Science.gov (United States)

Conflicting water uses in coastal zones demand integrated approaches to achieve sustainable water resources management, protecting water quality while allowing those human activities which rely upon aquatic ecosystem services to thrive. This case study shows that the creation and simple management of hydraulic structures within constructed wetlands can markedly reduce the non-point pollution from agriculture and, simultaneously, benefit agricultural activities, particularly during hot and dry periods. The Vallevecchia wetland system is based on a reclaimed 900 ha-large drainage basin in Northern Italy, where droughts recently impacted agriculture causing water scarcity and saltwater intrusion. Rainwater and drained water are recirculated inside the system to limit saltwater intrusion, provide irrigation water during dry periods and reduce the agricultural nutrient loads discharged into the bordering, eutrophic Adriatic Sea. Monitoring (2003-2009) of water quality and flows highlights that the construction (ended in 2005) of a gated spillway to control the outflow, and of a 200,000 m3 basin for water storage, dramatically increased the removal of nutrients within the system. Strikingly, this improvement was achieved with a minimal management effort, e.g., each year the storage basin was filled once: a simple management of the hydraulic structures would greatly enhance the system efficiency, and store more water to irrigate and limit saltwater intrusion. PMID:22053478

Carrer, G M; Bonato, M; Smania, D; Barausse, A; Comis, C; Palmeri, L

2011-01-01

344

Study of Plant Oil and its Ageing Effect on Hydraulic System Efficiency and Rheological Performance  

Directory of Open Access Journals (Sweden)

Full Text Available The effects of oil ageing on hydraulic system efficiency and oil rheological performance were studied. The various physical and chemical properties of fresh and aged oils were studied by determining total acid value, iodine value and density. The variation of oil functional group was analyzed by FTIR. The rheological behavior i.e., variation of viscosity with time, temperature and shear rate was studied using Brookfield viscometer. An attempt was made to establish the relationship between variation of viscosity and time of fresh and aged oil. The hydraulic performance has been investigated by determining system volumetric and mechanical efficiencies. The results show that the volumetric efficiency increases with ageing period while mechanical efficiency decreases when the oil ageing time increases.

W.B. Wan Nik

2007-01-01

345

A Study on Mission Profile and Determination of Durability Test Parameters in the Hydraulic Clutch System  

International Nuclear Information System (INIS)

One of reliability measurements of vehicle is estimated by driving mileage but the reliability of component, such as an hydraulic clutch system, is defined from the number of successful operational cycle. Relationship between these reliability measurement variables(mileage and cycle) should be examined first of all in the reliability estimation of components. Relationship between mileage and cycles is commonly known as linear function. However, the gradient depends on the operational environmental condition. Therefore, estimation of mission profile variable should be done with correlation analysis at the same time. In this paper, we derive mission profile variable of an hydraulic clutch system by field vehicle test and suggest the determination process of durability test parameters of CMC(Clutch Master Cylinder) with mission profile variable

346

Study of Plant Oil and its Ageing Effect on Hydraulic System Efficiency and Rheological Performance  

Science.gov (United States)

The effects of oil ageing on hydraulic system efficiency and oil rheological performance were studied. The various physical and chemical properties of fresh and aged oils were studied by determining total acid value, iodine value and density. The variation of oil functional group was analyzed by FTIR. The rheological behavior i.e., variation of viscosity with time, temperature and shear rate was studied using Brookfield viscometer. An attempt was made to establish the relationship between variation of viscosity and time of fresh and aged oil. The hydraulic performance has been investigated by determining system volumetric and mechanical efficiencies. The results show that the volumetric efficiency increases with ageing period while mechanical efficiency decreases when the oil ageing time increases.

Nik, W. B. Wan; Bulat, K. H. Ku; Senin, H. B.; Ali, N. A.; Rahman, M. D.; Ani, F. N.

347

Thermal hydraulic aspects of steam drum level control philosophy for the natural circulation based heavy water reactor  

International Nuclear Information System (INIS)

From safety considerations advanced nuclear reactors rely more and more on passive systems such as natural circulation for primary heat removal. A natural circulation based water reactor is relatively larger in size so as to reduce flow losses and channel type for proper flow distribution. From the size of steam drum considerations it has to be multi loop but has a common inlet header. Normally the turbine follows the reactor. This paper addresses the thermal hydraulic aspects of the steam drum pressure and level control philosophy for a four drum, natural circulation based, channel type boiling water advanced reactor. Three philosophies may be followed for drum control viz. individual drum control, one control drum approach and an average of all the four drums. For drum pressure control, the steam flow to the turbine is be regulated. A single point pressure control is better than individual drum pressure control. This is discussed in the paper. But the control point has to be at a place down steam the point where all steam line from individual drum meet. This may lead to different pressure in all the four drums depending on the power produced in the respective loops. The difference in pressure cannot be removed even if the four drums are directly connected through pipes. Also the pressure control scheme with/without interconnection is discussed. For level, the control of individual drum may not be normally possible because of common inlet header. As the frictional pr common inlet header. As the frictional pressure drops in the large diameter downcomers are small as compared to elevation pressure drops, the level in all the steam drum tend to equalize. Consequently a single representative drum level may be chosen as a control variable for controlling level in all the four drums. But in case, where all the four loops are producing different powers and single point pressure control is effective, the scheme may not work satisfactorily. the level in a drum may depend on the power produced in the loop containing the control drum. In that case a scheme based on the average of all the four steam drum levels works better. Response of a single point pressure control together with average level control philosophy to various operational transients is also presented. (author)

348

Thermal-hydraulic characteristics of safety systems of advanced reactors  

International Nuclear Information System (INIS)

The heat transfer rates that occur inside and outside surfaces of the passive containment cooling system with both dry and wet outer containment surface following a postulated accident were investigated. The test model represented a 60 section of a containment vessel based on the AP600 geometry. The natural convective heat transfer from the containment to the air without water film flow was exceeded the expected values. Water film flow for the containment cooling is very effective to maintain the integrity of the structure of containment during postulated accident the local heat removal rate at the top of the dome is significantly higher than the average removal rate. (Author)

349

Challenges in thermal and hydraulic analysis of ADS target systems  

International Nuclear Information System (INIS)

The liquid metal cooled spallation targets of Accelerator Driven nuclear reactor Systems obey high thermal loads; in addition some flow and cooling conditions are of a prototypical character; in contrast the operating conditions for the engaged materials are narrow; thus, the target development requires a very careful analysis by experimental and numerical means. Especially the cooling of the steel window, which is heated by the proton beam, needs special care. Some of the main goals of the experimental and numerical analyses of the thermal dynamics of those systems are discusses. The prediction of locally detached flows and of flows with larger recirculation areas suffers from insufficient turbulence modeling; this has to be compensated by using prototypical model experiments, e.g. with water, to select the adequate models and numerical schemes. The well known problems with the Reynolds analogy in predicting the heat transfer in liquid metals requires always prototypic liquid metal experiments to select and adapt the turbulent heat flux models. The uncertainties in liquid metal experiments cannot be neglected; so it is necessary to perform CFD calculations and experiments always hand in hand and to develop improve turbulent heat flux models. One contribution to an improved 3 or 4-equation model is deduced from recent Direct Numerical Simulation (DNS) data. (author)

350

Modeling and Simulation of an Active Hydraulic Heave Compensation System for Offshore Cranes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This thesis deals with the mathematical modeling of hydraulic heave compensation systems. When performing operations such as launch and recovery of remote operated vehicles and lowering subsea installation parts to the sea floor, it is important to attenuate unwanted load motion caused by elongation of the cable and heave motion of the vessel. Quite often, such operations must be put off while waiting for the weather to calm down. Extending the window of operations by developing equipme...

Sverdrup-thygeson, Jřrgen

2007-01-01

351

Thermal-hydraulic analysis of WWER-440 spent-fuel storage systems  

International Nuclear Information System (INIS)

In the framework of the contract between IAEA and the KFKI Atomic Energy research Institute, numerical models have been developed for the simulation and thermal-hydraulic behaviour of CASTOR type spent fuel storage constructed at Dukovany NPP and MVDS type spent fuel storage operated by Paks NPP with WWER-440 fuel. The model is based on the code COBRA-SFS which is well validated for spent fuel storage system with western PWR and BWR type fuels

352

Dynamic modeling of the servovalves incorporated in the servo hydraulic system of the 70-meter DSN antennas  

Science.gov (United States)

As the pointing accuracy and service life requirements of the DSN 70 meter antenna increase, it is necessary to gain a more complete understanding of the servo hydraulic system in order to improve system designs to meet the new requirements. A mathematical model is developed for the servovalve incorporated into the hydraulic system of the 70 meter antenna and uses experimental data to verify the validity of the model and to identify the model parameters.

Bartos, R. D.

1992-01-01

353

ISABELLE control system  

International Nuclear Information System (INIS)

Design principles for the Brookhaven ISABELLE control intersecting storage ring accelerator are described. Principal features include a locally networked console and control computer complex, a system wide process data highway, and intelligent local device controllers. Progress to date is summarized

354

COMPARISON OF GENETIC FUZZY SYSTEM AND NEURO FUZZY SYSTEM FOR THE SELECTION OF OIL WELLS FOR HYDRAULIC FRACTURING  

Directory of Open Access Journals (Sweden)

Full Text Available The hydraulic fracture operation is wide used to increase the oil wells production and to reduce formation damage. Reservoir studies and engineer analysis are made to select the wells for this kind of operation. As the reservoir parameters have some diffuses characteristics, Fuzzy Inference Systems (SIF have been tested for this selection processes in the last few years. This paper compares the performance of a neuro fuzzy system and a genetic fuzzy system used for hydraulic Fracture well selection, with knowledge acquisition from an operational data base to set the SIF membership functions. The training data and the validation data used were the same for both systems. We concluded that, in despite of the genetic fuzzy system would be a younger process, it got better results than the neuro fuzzy system. Another conclusion was that, as the genetic fuzzy system can work with constraints, the membership functions setting kept the consistency of variables linguistic values.

Antônio Orestes de Salvo Castro

2007-06-01

355

Control and automation systems  

International Nuclear Information System (INIS)

A survey is given of the development of control and automation systems for energy uses. General remarks about control and automation schemes are followed by a description of modern process control systems along with process control processes as such. After discussing the particular process control requirements of nuclear power plants the paper deals with the reliability and availability of process control systems and refers to computerized simulation processes. The subsequent paragraphs are dedicated to descriptions of the operating floor, ergonomic conditions, existing systems, flue gas desulfurization systems, the electromagnetic influences on digital circuits as well as of light wave uses. (HAG)

356

The remote control system  

International Nuclear Information System (INIS)

The remote-control system is applied in order to control various signals in the car of the spectrometer at distance. The construction (hardware and software) as well as the operation of the system is described. (author). 20 figs

357

SCADA of an Upstream Controlled Irrigation Canal System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Upstream control in canals is efficient only when associated with rigid water delivery methods. In Portugal, all of the upstream controlled systems work with flexible water delivery schedules and, for this reason, operational water losses become significant. Because there is no storage reserve inside this kind of systems it is necessary to take into account the demand prediction or the command anticipation of the hydraulic control devices in order to improve the system response to demand vari...

Rijo, Manuel

1999-01-01

358

Thermal–hydraulic system study of the HELOKA-LP helium loop using RELAP5-3D code  

Energy Technology Data Exchange (ETDEWEB)

Highlights: • Thermal–hydraulic system study for the HELOKA-LP using RELAP5-3D. • Validation of various experiments with corresponding simulations, and good comparison between the experiments and the simulations. • Simulation of the two most heated compartments of IFMIF HFTM in the modeled helium loop and prediction of the loop dynamic. -- Abstract: The thermal–hydraulic system analyses for the HELOKA-LP (Helium Loop Karlsruhe – Low Pressure) facility are presented. Typical operation ranges for the test section are mass flow rate between 12 and 120 g/s, inlet temperature between 10 and 250 °C and pressure level between 0.3 and 0.6 MPa. An orifice is used for the loop testing, for which different experiments are validated with appropriate simulations. Afterwards instead of the orifice, two most heated compartments of IFMIF (International Fusion Materials Irradiation Facility) HFTM (high flux test module) are simulated in HELOKA-LP. Using the system code REALP5-3D components in the loop are modeled as well as the main control strategy. With this model the loop dynamics in conditions relevant for the HFTM operation are analyzed and the thermal time constant of the compartment is estimated.

Jin, Xue Zhou, E-mail: jin@kit.edu; Schlindwein, Georg; Schlenker, Markus; Ghidersa, Bradut-Eugen; Chen, Yuming; Arbeiter, Frederik

2013-10-15

359

Thermal–hydraulic system study of the HELOKA-LP helium loop using RELAP5-3D code  

International Nuclear Information System (INIS)

Highlights: • Thermal–hydraulic system study for the HELOKA-LP using RELAP5-3D. • Validation of various experiments with corresponding simulations, and good comparison between the experiments and the simulations. • Simulation of the two most heated compartments of IFMIF HFTM in the modeled helium loop and prediction of the loop dynamic. -- Abstract: The thermal–hydraulic system analyses for the HELOKA-LP (Helium Loop Karlsruhe – Low Pressure) facility are presented. Typical operation ranges for the test section are mass flow rate between 12 and 120 g/s, inlet temperature between 10 and 250 °C and pressure level between 0.3 and 0.6 MPa. An orifice is used for the loop testing, for which different experiments are validated with appropriate simulations. Afterwards instead of the orifice, two most heated compartments of IFMIF (International Fusion Materials Irradiation Facility) HFTM (high flux test module) are simulated in HELOKA-LP. Using the system code REALP5-3D components in the loop are modeled as well as the main control strategy. With this model the loop dynamics in conditions relevant for the HFTM operation are analyzed and the thermal time constant of the compartment is estimated

360

Summary of the hydraulic evaluation of LWBR (LWBR development program)  

International Nuclear Information System (INIS)

The principal hydraulic performance features of the Light Water Breeder Reactor are summarized in this report. The calculational models and procedures used for prediction of reactor flow and pressure distributions under steady-state and transient operating conditions are described. Likewise, the analysis models for evaluation of the static and dynamic performance characteristics of the hydraulically-balanced and hydraulically-buffered movable-fuel reactivity-control system are outlined. An extensive test program was conducted for qualification of the subject LWBR hydraulic evaluation models. The projected LWBR hydraulic performance is shown to fulfill design objectives and functional requirements

 
 
 
 
361

Application of Discrete Event Control to the Insertion Task of Electric Line Using 6-Link Electro-Hydraulic Manipulators with Dual Arm  

Science.gov (United States)

Uninterrupted power supply has become indispensable during the maintenance task of active electric power lines as a result of today's highly information-oriented society and increasing demand of electric utilities. The maintenance task has the risk of electric shock and the danger of falling from high place. Therefore it is necessary to realize an autonomous robot system using electro-hydraulic manipulator because hydraulic manipulators have the advantage of electric insulation. Meanwhile it is relatively difficult to realize autonomous assembly tasks particularly in the case of manipulating flexible objects such as electric lines. In this report, a discrete event control system is introduced for automatic assembly task of electric lines into sleeves as one of a typical task of active electric power lines. In the implementation of a discrete event control system, LVQNN (learning vector quantization neural network) is applied to the insertion task of electric lines to sleeves. In order to apply these proposed control system to the unknown environment, virtual learning data for LVQNN was generated by fuzzy inference. By the experimental results of two types of electric lines and sleeves, these proposed discrete event control and neural network learning algorithm are confirmed very effective to the insertion tasks of electric lines to sleeves as a typical task of active electric power maintenance tasks.

Ahn, Kyoungkwan; Yokota, Shinichi

362

Influence of geometrical and thermal hydraulic parameters on the short term containment system response  

International Nuclear Information System (INIS)

This paper discusses the effect of a number of geometrical and thermal hydraulic parameters on the containment peak pressure following a simulated LOCA. The numerical studies are carried out using an inhouse containment thermal hydraulics program called 'THYCON' with focus only on the short term transient response. In order to highlight the effect of above variables, a geometrically scaled (1:270) model of a typical 220 MWe Indian PHWR containment is considered. The discussions in this paper are limited to explaining the influence of individual parameters by comparing with a base case value. It is essential to mention that the results presented here are not general and should be taken as indicative only. Nevertheless, these numerical studies give insight into short term containment response that would be useful to both the system designer as well as the regulator. (author)

363

Thermal-hydraulic design concept of the solid-target system of spallation neutron source  

International Nuclear Information System (INIS)

In relation to thermal-hydraulic design of the N-Arena solid-target system of the JHF project, heat transfer experiments were performed to obtain experimental data systematically on heat transfer coefficient and CHF for vertical upward and horizontal flows in a thin rectangular channel simulating a coolant channel of the proposed spallation neutron source. Thermal-hydraulic correlations which can be used for design calculations were proposed based on the obtained data. Finally tentative results of feasibility study on maximum beam power which could be attained with a solid target were presented. The result indicated that the condition for the onset of nucleate boiling is the most significant limiting factor to the maximum beam power. (author)

364

Thermal-hydraulic design concept of the solid-target system of spallation neutron source  

Energy Technology Data Exchange (ETDEWEB)

In relation to thermal-hydraulic design of the N-Arena solid-target system of the JHF project, heat transfer experiments were performed to obtain experimental data systematically on heat transfer coefficient and CHF for vertical upward and horizontal flows in a thin rectangular channel simulating a coolant channel of the proposed spallation neutron source. Thermal-hydraulic correlations which can be used for design calculations were proposed based on the obtained data. Finally tentative results of feasibility study on maximum beam power which could be attained with a solid target were presented. The result indicated that the condition for the onset of nucleate boiling is the most significant limiting factor to the maximum beam power. (author)

Tanaka, F.; Hibiki, T.; Saito, Y.; Takeda, T.; Mishima, K. [Kyoto Univ., Research Reactor Institute (Japan)

2001-07-01

365

Software Tool for Automated Failure Modes and Effects Analysis (FMEA) of Hydraulic Systems  

DEFF Research Database (Denmark)

Offshore, marine,aircraft and other complex engineering systems operate in harsh environmental and operational conditions and must meet stringent requirements of reliability, safety and maintability. To reduce the hight costs of development of new systems in these fields improved the design management techniques and a vast array of computer aided techniques are applied during design and testing stages. The paper present and discusses the research and development of a software tool for automated failure mode and effects analysis - FMEA - of hydraulic systems. The paper explains the underlying principles of the software during operation, and provides a description of the software.

Conrad, Finn

2002-01-01

366

Design and Development of Double Wishbone Electro-Hydraulic Active Suspension System  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract : This paper is a literature survey for the electro Design and development of Double electro-hydraulic active suspension system. It is divided into three section viz. literature survey, methodology adapted and design procedure and experimentation. In literature survey. we find the theoretical information regarding the various suspension systems, performance and find the way of work. Methodology consist of different part of systems like spring, drive pinion, rack, helical cam, follower pin and push rod. Design and Experimental result to evaluate Performance of prepared model it is placed over exciter and variable load is applied over it through strut arrangement.

Mr. K. S. Patil, Prof.V. R. Gambhire

2014-06-01

367

CONTROL SYSTEM ANALYSIS AND SYNTHESIS OF MACHINE TOOL DOORS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Processing machines have a safety door with a manual closing system. To import automatic system in this kind of machines, we had analyzed, which system would be most proper to install. On one hand, we have pneumatic system control and on other hydraulic system. Both are presented separately and modeled in program Automation Studio, regarding to construction. In both cases we optimized the system and measured responses. At the end we compared them regarding to maintenance, system costs and sim...

Ferme, Gas?per

2011-01-01

368

Resolution of thermal-hydraulic safety and licensing issues for the system 80+trademark design  

International Nuclear Information System (INIS)

The System 80+trademark Standard Design is an evolutionary Advanced Light Water Reactor (ALWR) with a generating capacity of 3931 MWt (1350 MWe). The Final Design Approval (FDA) for this design was issued by the Nuclear Regulatory Commission (NRC) in July 1994. The design certification by the NRC is anticipated by the end of 1995 or early 1996. NRC review of the System 80+ design has involved several new safety issues never before addressed in a regulatory atmosphere. In addition, conformance with the Electric Power Research Institute (EPRI) ALWR Utility Requirements Document (URD) required that the System 80+ plant address nuclear industry concerns with regard to design, construction, operation and maintenance of nuclear power plants. A large number of these issues/concerns deals with previously unresolved generic thermal-hydraulic safety issues and severe accident prevention and mitigation. This paper discusses the thermal-hydraulic analyses and evaluations performed for the System 80+ design to resolve safety and licensing issues relevant to both the Nuclear Stream Supply System (NSSS) and containment designs. For the NSSS design, the Safety Depressurization System mitigation capability and resolution of the boron dilution concern are described. Examples of containment design issues dealing with containment shell strength, robustness of the reactor cavity walls and hydrogen mixing under severe accident conditions are also provided. Finally, the overall approach used in the application of NRC's new (NUREG-1465) radiological source term for System 80+ evaluation is described. The robustness of the System 80+ containment design to withstand severe accident consequences was demonstrated through detailed thermal-hydraulic analyses and evaluations. This advanced design to shown to meet NRC severe accident policy goals and ALWR URD requirements without any special design features and unnecessary costs

369

Resolution of thermal-hydraulic safety and licensing issues for the system 80+{sup {trademark}} design  

Energy Technology Data Exchange (ETDEWEB)

The System 80+{sup {trademark}} Standard Design is an evolutionary Advanced Light Water Reactor (ALWR) with a generating capacity of 3931 MWt (1350 MWe). The Final Design Approval (FDA) for this design was issued by the Nuclear Regulatory Commission (NRC) in July 1994. The design certification by the NRC is anticipated by the end of 1995 or early 1996. NRC review of the System 80+ design has involved several new safety issues never before addressed in a regulatory atmosphere. In addition, conformance with the Electric Power Research Institute (EPRI) ALWR Utility Requirements Document (URD) required that the System 80+ plant address nuclear industry concerns with regard to design, construction, operation and maintenance of nuclear power plants. A large number of these issues/concerns deals with previously unresolved generic thermal-hydraulic safety issues and severe accident prevention and mitigation. This paper discusses the thermal-hydraulic analyses and evaluations performed for the System 80+ design to resolve safety and licensing issues relevant to both the Nuclear Stream Supply System (NSSS) and containment designs. For the NSSS design, the Safety Depressurization System mitigation capability and resolution of the boron dilution concern are described. Examples of containment design issues dealing with containment shell strength, robustness of the reactor cavity walls and hydrogen mixing under severe accident conditions are also provided. Finally, the overall approach used in the application of NRC`s new (NUREG-1465) radiological source term for System 80+ evaluation is described. The robustness of the System 80+ containment design to withstand severe accident consequences was demonstrated through detailed thermal-hydraulic analyses and evaluations. This advanced design to shown to meet NRC severe accident policy goals and ALWR URD requirements without any special design features and unnecessary costs.

Carpentino, S.E.; Ritterbusch, S.E.; Schneider, R.E. [ABB-Combustion Engineering, Windsor, CT (United States)] [and others

1995-09-01

370

Interaction between thermal/hydraulics, human factors and system analysis for assessing feed and bleed risk benefits  

International Nuclear Information System (INIS)

For probabilistic analysis of accident sequences, thermal/hydraulics, human factors and systems operation problems are frequently closely interrelated. This presentation will discuss a typical example which illustrates this interrelation: total loss of feedwater flow. It will present thermal/hydraulic analysises performed, how the T/H analysises are related to human factors and systems operation, and how, based on this, the failure probability of the feed and bleed cooling mode was evaluated

371

Integrated control systems  

International Nuclear Information System (INIS)

This paper reports that instrument manufacturers must develop standard network interfaces to pull together interrelated systems such as automatic start-up, optimization programs, and online diagnostic systems. In the past individual control system manufacturers have developed their own data highways with proprietary hardware and software designs. In the future, electric utilities will require that future systems, irrespective of manufacturer, should be able to communicate with each other. Until now the manufactures of control systems have not agreed on the standard high-speed data highway system. Currently, the Electric Power Research Institute (EPRI), in conjunction with several electric utilities and equipment manufactures, is working on developing a standard protocol for communicating between various manufacturers' control systems. According to N. Michael of Sargent and Lundy, future control room designs will require that more of the control and display functions be accessible from the control room through CRTs. There will be less emphasis on traditional hard-wired control panels

372

Development and verification of the MASTER dynamic link library (DLL) for integration into a system thermal-hydraulics code  

International Nuclear Information System (INIS)

The dynamic link library (DLL) of the MASTER code has been generated and verified for the use in code coupling to build an integrated nuclear power plant transient analysis code by combining the three-dimensional neutron kinetic code with a system thermal-hydraulic code. For the generation of the MASTER DLL, the link variables needed for incorporating thermal feedback effects were identified first and a data exchange scheme was established. The MASTER code was modified such that it can run on the Windows operating system and a couple of newly written link subroutines were added to generate the DLL. For the standalone verification of the DLL, a coupled code was built by using a simple thermal-hydraulic code and the DLL and the coupled code was applied to the NEACRP benchmark problems, which offer a variety of steady state and control rod ejection calculations. The verification was done by comparing the results of the coupled code calculations were compared with corresponding MASTER standalone calculations. In addition, a set of sensitivity studies were performed to check the sound operation of the neutronic /T-H calculations. It was made sure based on these verifications that the generated MASTER DLL is sound and work properly. (author). 5 refs., 7 tabs., 14 figs

373

Development of a computational system for coupled neutronic, thermal-hydraulic and structural analysis using message passing interface  

International Nuclear Information System (INIS)

A prototype computational system for simulating coupled neutronic, thermal-hydraulic, and structural behaviors in a liquid-metal fast reactor (LMFR) core has been developed for the ultimate purpose of establishing an environment of numerical experiments, where one can virtually experience and observe complex physical phenomena occurring in a fast reactor core. The system takes into consideration the distortion of power density distribution and reactivity feedback due to core deformation, which reflects the change of coolant temperature through various reactivity feedback effects. It was also attempted to minimize data communication time among the coupled codes and the large work loads for maintenance. Instead of the conventional way of importing and exporting data files, a specific message passing library is used for the efficient data communication between analysis codes. This system consists of ; four existing large-scale codes, which analyze reactor core characteristics, reactivity worth based on perturbation theory, plant dynamics and core deformation ; interface modules for data transfer between the codes ; and a master program for control of the system. In addition, the connection between these four codes by two interface programs allows us to update the system easily when a physical model in each code has to be modified. To demonstrate the applicability and usefulness of the system, a series of calculations were attempted for simulating a sequence of a hypothetical loss of heat sink in an LMFR. It was shown that the reactor core analysis system developed in this study can adequately simulate coupled neutronic, thermal-hydraulic and structural phenomena with both reasonable computational time and small loads required to update the system. (author)

374

Fabrication and test of hydraulic jacks for the application to divertor support system of fusion experimental reactor  

International Nuclear Information System (INIS)

This paper reports on two different types of hydraulic jacks consisting of hydraulic piston and bellows which were developed for an application to locking and lifting systems for divertor segments for Fusion Experimental Reactor. For the lifting system where a minimum stroke of 170 mm was required, the telescopic-type hydraulic jack with a length of 300 mm was fabricated and tested under an operation pressure of 1 MPa. for the locking system, the hydraulic jack with the conical cotter was developed that worked at 6.5 MPa under a radial offset of 2 mm. These jacks satisffied their specifications without any leakage, failure and abrasion. Performance of several hard facing materials for the cotter was also examined including alumina and metal alloys. The colmony no. 5 or stellite alloy no. 6 was found to be excellent as a hard facing material for the cotter

375

Design and Experimental Validation of Hydraulic Yaw System for Multi MW Wind Turbine  

DEFF Research Database (Denmark)

To comply with the increasing demands for life time and reliability of wind turbines as these grow in size, new measures needs to be taken in the design of wind turbines and components hereof. One critical point is the initial testing of the components and systems before they are implemented in an actual turbine. Full scale hardware testing is both extremely expensive and time consuming, and so the wind turbine industry moves more towards simulations when testing. In order to meet these demands it is necessary with valid models of systems in order to introduce new technologies to the wind turbine market. A hydraulic yaw system is such a new technology, and so a mathematical model of the full scale system and test rig system is derived and compared to measurements from the system. This is done in order to have a validated model, which wind turbine manufacturers may use for test in their simulation environment. The model and the test rig are tested up against different design load cases and the results are compared. The experiments show that the model is valid for comparing the overall dynamics of the hydraulic yaw system. Based on the results it is concluded that the model derived is suitable for testing of the dynamic behavior in wind turbine manufacturer’s full scale aero elastic code.

Stubkier, SŘren; Pedersen, Henrik C.

2013-01-01

376

The coupled neutronics and thermal hydraulics code system PANBOX for PWR safety analysis  

International Nuclear Information System (INIS)

PANBOX is used for reload safety analysis and all kinds of transients in which the power distribution is significantly affected. Apart from input and output processors it consists of dedicated modules which treat specific transients such as long-term events like xenon redistribution and short-term accidents like rod ejections. Theory, application and verification of the system are described. The global solution is combined with an accurate and efficient pin power reconstruction module. Thus the system is capable of performing global neutronic/thermal-hydraulic calculations and of evaluating important safety-related parameters, such as departure from nucleate boiling ratios and centreline fuel temperatures. (orig./HP)

377

Hydraulic model of the proposed Water Recovery and Management system for Space Station Freedom  

Science.gov (United States)

A model of the Water Recovery and Management (WRM) system utilizing SINDA '85/FLUINT to determine its hydraulic operation characteristics, and to verify the design flow and pressure drop parameters is presented. The FLUINT analysis package is employed in the model to determine the flow and pressure characteristics when each of the different loop components is operational and contributing to the overall flow pattern. The water is driven in each loop by storage tanks pressurized with cabin air, and is routed through the system to the desired destination.

Martin, Charles E.; Bacskay, Allen S.

1991-01-01

378

Virtual Training System for Hydraulic Pump Cart Based on Virtual Reality  

Directory of Open Access Journals (Sweden)

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.  

Wusha Huang

2013-08-01

379

Analysis of the Power Head Torque Loading System Based on Hydraulic Energy Closed-loop  

Directory of Open Access Journals (Sweden)

Full Text Available Power head with high power and large torque is the main power equipment of the rotary drilling rig. Aimed at the working condition, energy saving torque loading test program of power head was put forward and mathematical and simulation models of hydraulic energy closed-loop torque loading system were established in order to make an analysis of torque loading system. Combined with bond graph and state equations of torque loading system with single pump, effect of the logical relationship of discharge between the driving motor and loading pump and the relationship between the adjusting proportion of series and parallel pressure on the torque loading system was analyzed because both hydraulic flow and pressure can have an influence on the system stability. It proves that the torque loading system is stable when the adjusting proportion of series pressure is larger than that of the parallel pressure. Otherwise, it needs to consider the discharge trend between the power motor and loading pump.

Xianjin Shi

2013-07-01

380

Modeling and Simulation of Valve-controlled Cylinder System Based on Bond Graph  

Directory of Open Access Journals (Sweden)

Full Text Available AMESim is a high performance modeling, simulation and dynamic analysis software. Based on the bond graph theory and the principle of hydraulic control, a simulation model of valve-controlled cylinder system in EPS fatigue testing bench is established by using AMESim software. By changing different factors of the hydraulic system and setting different target wave curves, the system effects with different conditions are discussed and the simulation results provide a theoretical guidance for modeling optimization.

Wang Qi

2012-08-01

 
 
 
 
381

A modular control system  

International Nuclear Information System (INIS)

The main objective of the modular control system is to provide the requirements to most of the processes supervision and control applications within the industrial automatization area. The design is based on distribution, modulation and expansion concepts. (Author)

382

Motion control systems  

CERN Document Server

"Presents a unified approach to the fundamental issues in motion control, starting from the basics and moving through single degree of freedom and multi-degree of freedom systems In Motion Control Systems, S?abanovic and Ohnishi present a unified approach to very diverse issues covered in motion control systems, offering know-how accumulated through work on very diverse problems into a comprehensive, integrated approach suitable for application in high demanding high-tech products. It covers material from single degree of freedom systems to complex multi-body non-redundant and redundant systems. The discussion of the main subject is based on original research results and will give treatment of the issues in motion control in the framework of the acceleration control method with disturbance rejection technique. This allows consistent unification of different issues in motion control ranging from simple trajectory tracking to topics related to haptics and bilateral control without and with delay in the measure...

Sabanovic, Asif

2011-01-01

383

Identification and real-time position control of a servo-hydraulic rotary actuator by means of a neurobiologically motivated algorithm.  

Science.gov (United States)

This paper presents a new intelligent approach for adaptive control of a nonlinear dynamic system. A modified version of the brain emotional learning based intelligent controller (BELBIC), a bio-inspired algorithm based upon a computational model of emotional learning which occurs in the amygdala, is utilized for position controlling a real laboratorial rotary electro-hydraulic servo (EHS) system. EHS systems are known to be nonlinear and non-smooth due to many factors such as leakage, friction, hysteresis, null shift, saturation, dead zone, and especially fluid flow expression through the servo valve. The large value of these factors can easily influence the control performance in the presence of a poor design. In this paper, a mathematical model of the EHS system is derived, and then the parameters of the model are identified using the recursive least squares method. In the next step, a BELBIC is designed based on this dynamic model and utilized to control the real laboratorial EHS system. To prove the effectiveness of the modified BELBIC's online learning ability in reducing the overall tracking error, results have been compared to those obtained from an optimal PID controller, an auto-tuned fuzzy PI controller (ATFPIC), and a neural network predictive controller (NNPC) under similar circumstances. The results demonstrate not only excellent improvement in control action, but also less energy consumption. PMID:22015061

Sadeghieh, Ali; Sazgar, Hadi; Goodarzi, Kamyar; Lucas, Caro

2012-01-01

384

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

Science.gov (United States)

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

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

2010-06-01

385

Intelligent multivariable control system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The objective of this study is to develop an intelligent controller for general nonlinear multivariable systems and implement it in complex grinding processes. Conventional control techniques require a precise analytical model. Fuzzy controllers offer a promising alternative as the system dynamics is captured by human knowledge and experimental data rather than by an accurate analytical model. ^ In this work, a Multi-Level Fuzzy Controller (MLFC) is developed for a general Single-Input Sing...

Xu, Chengying

2006-01-01

386

Neural daylight control system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The paper describes the design, the implementation of a neural controller used in an automatic daylight control system. The automatic lighting control system (ALCS) attempt to maintain constant the illuminance at the desired level on working plane even if the daylight contribution is variable. Therefore, the daylight will represent the perturbation signal for the ALCS. The mathematical model of process is unknown. The applied structure of control need the inverse model of pr...

Grif, Horatiu Stefan

2010-01-01

387

Applied Control Systems Design  

CERN Document Server

Applied Control System Design examines several methods for building up systems models based on real experimental data from typical industrial processes and incorporating system identification techniques. The text takes a comparative approach to the models derived in this way judging their suitability for use in different systems and under different operational circumstances. A broad spectrum of control methods including various forms of filtering, feedback and feedforward control is applied to the models and the guidelines derived from the closed-loop responses are then composed into a concrete self-tested recipe to serve as a check-list for industrial engineers or control designers. System identification and control design are given equal weight in model derivation and testing to reflect their equality of importance in the proper design and optimization of high-performance control systems. Readers’ assimilation of the material discussed is assisted by the provision of problems and examples. Most of these e...

Mahmoud, Magdi S

2012-01-01

388

Numerical hydraulic modeling of urban waste water collecting systems : Working Project at Chazelles-sur-Lyon, France  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Urban waste water collecting systems are designed to convey domestic, industrial and storm water. When sizing sewer network, heavy rainfall must be considered to provide the needed hydraulic capacity for collection. Maintenance is also required in order to avoid anomalies such as inflow, infiltration and unusual polluted discharges from Combined Sewer Overflows (CSOs). Inflow and infiltration decrease the treatment yield at the Waste water Treatment Plant (WWTP) and participate in hydraulic o...

Genty, Stanislas

2014-01-01

389

Developing Automatic Controllers for sprinkler irrigation systems  

Science.gov (United States)

The application of new technologies to the control and automation of irrigation processes is quickly gaining attention. The automation of irrigation execution (through irrigation controllers) is now widespread. However, the automatic generation and execution of irrigation schedules is receiving growing attention due to the possibilities offered by the telemetry/remote control systems currently being installed in collective pressurized networks. These developments can greatly benefit from the combination of irrigation system and crop models, and from the interaction with agrometeorological databases, hydraulic models of pressurized collective distribution networks, weather forecasts and management databases for water users associations. Prospects for the development of such systems in collective sprinkler irrigation systems are analyzed in this presentation. Additionally, experimental results are presented on the application of these concepts to a hydrant irrigating a solid-set irrigated maize field.

Playán, E.; Salvador, R.; Cavero, J.; López, C.; Lecina, S.; Zapata, N.

2012-04-01

390

Control and optimization system  

Energy Technology Data Exchange (ETDEWEB)

A system for optimizing a power plant includes a chemical loop having an input for receiving an input parameter (270) and an output for outputting an output parameter (280), a control system operably connected to the chemical loop and having a multiple controller part (230) comprising a model-free controller. The control system receives the output parameter (280), optimizes the input parameter (270) based on the received output parameter (280), and outputs an optimized input parameter (270) to the input of the chemical loop to control a process of the chemical loop in an optimized manner.

Xinsheng, Lou

2013-02-12

391

Control rod drive water supply system  

International Nuclear Information System (INIS)

Purpose: To prevent atmospheric corrosion within a reactor container of a control rod drive hydraulic system which is closely disposed and hard to repair from outside. Constitution: In a BWR type nuclear power plant, drive water which is supplied to hydraulically driven control rod drives is taken from a condensate feedwater system. That is, the drive water is supplied from a control rod drive water intake line connected to a water supply port of a condensate desalting equipment and from a branch line of a water supply line of a feedwater heater, thereby raising a drive water temperature and lowering the relative humidity of the atmosphere in the vicinity of the piping surface, to prevent the occurrence of SCC of the piping by the atmospheric corrosion. Since the drive water is taken from the Low-Dissolved oxygen system water of the nuclear power plant, there is very little possibility of water entrance into the reactor. Furthermore, low construction cost and plant maintenance cost as well as a simplified system can be realized without installing a heater to the drive water pressure system. (Kawakami, Y.)

392

46 CFR 58.30-10 - Hydraulic fluid.  

Science.gov (United States)

...2010-10-01 2010-10-01 false Hydraulic fluid. 58.30-10 Section 58.30-10...AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-10 Hydraulic fluid. (a) The requirements of this...

2010-10-01

393

Creation of an Enhanced Geothermal System through Hydraulic and Thermal Stimulation  

Energy Technology Data Exchange (ETDEWEB)

This report describes a 10-year DOE-funded project to design, characterize and create an Engineered Geothermal System (EGS) through a combination of hydraulic, thermal and chemical stimulation techniques. Volume 1 describes a four-year Phase 1 campaign, which focused on the east compartment of the Coso geothermal field. It includes a description of the geomechanical, geophysical, hydraulic, and geochemical studies that were conducted to characterize the reservoir in anticipation of the hydraulic stimulation experiment. Phase 1 ended prematurely when the drill bit intersected a very permeable fault zone during the redrilling of target stimulation well 34-9RD2. A hydraulic stimulation was inadvertently achieved, however, since the flow of drill mud from the well into the formation created an earthquake swarm near the wellbore that was recorded, located, analyzed and interpreted by project seismologists. Upon completion of Phase 1, the project shifted focus to a new target well, which was located within the southwest compartment of the Coso geothermal field. Volume 2 describes the Phase 2 studies on the geomechanical, geophysical, hydraulic, and geochemical aspects of the reservoir in and around target-stimulation well 46A-19RD, which is the deepest and hottest well ever drilled at Coso. Its total measured depth exceeding 12,000 ft. It spite of its great depth, this well is largely impermeable below a depth of about 9,000 ft, thus providing an excellent target for stimulation. In order to prepare 46A-19RD for stimulation, however, it was necessary to pull the slotted liner. This proved to be unachievable under the budget allocated by the Coso Operating Company partners, and this aspect of the project was abandoned, ending the program at Coso. The program then shifted to the EGS project at Desert Peak, which had a goal similar to the one at Coso of creating an EGS on the periphery of an existing geothermal reservoir. Volume 3 describes the activities that the Coso team contributed to the Desert Peak project, focusing largely on a geomechanical investigation of the Desert Peak reservoir, tracer testing between injectors 21-2 and 22-22 and the field�s main producers, and the chemical stimulation of target well 27-15.

Rose, Peter Eugene [Energy and Geoscience Institute at the Univerity of Utah

2013-04-15

394

Creation of an Enhanced Geothermal System through Hydraulic and Thermal Stimulation  

Energy Technology Data Exchange (ETDEWEB)

This report describes a 10-year DOE-funded project to design, characterize and create an Engineered Geothermal System (EGS) through a combination of hydraulic, thermal and chemical stimulation techniques. Volume 1 describes a four-year Phase 1 campaign, which focused on the east compartment of the Coso geothermal field. It includes a description of the geomechanical, geophysical, hydraulic, and geochemical studies that were conducted to characterize the reservoir in anticipation of the hydraulic stimulation experiment. Phase 1 ended prematurely when the drill bit intersected a very permeable fault zone during the redrilling of target stimulation well 34-9RD2. A hydraulic stimulation was inadvertently achieved, however, since the flow of drill mud from the well into the formation created an earthquake swarm near the wellbore that was recorded, located, analyzed and interpreted by project seismologists. Upon completion of Phase 1, the project shifted focus to a new target well, which was located within the southwest compartment of the Coso geothermal field. Volume 2 describes the Phase 2 studies on the geomechanical, geophysical, hydraulic, and geochemical aspects of the reservoir in and around target-stimulation well 46A-19RD, which is the deepest and hottest well ever drilled at Coso. Its total measured depth exceeding 12,000 ft. It spite of its great depth, this well is largely impermeable below a depth of about 9,000 ft, thus providing an excellent target for stimulation. In order to prepare 46A-19RD for stimulation, however, it was necessary to pull the slotted liner. This proved to be unachievable under the budget allocated by the Coso Operating Company partners, and this aspect of the project was abandoned, ending the program at Coso. The program then shifted to the EGS project at Desert Peak, which had a goal similar to the one at Coso of creating an EGS on the periphery of an existing geothermal reservoir. Volume 3 describes the activities that the Coso team contributed to the Desert Peak project, focusing largely on a geomechanical investigation of the Desert Peak reservoir, tracer testing between injectors 21-2 and 22-22 and the field�������¢����������������s main producers, and the chemical stimulation of target well 27-15.

Rose, Peter Eugene [Energy and Geoscience Institute at the University of Utah

2013-04-15

395

The ILC control system  

International Nuclear Information System (INIS)

Since the last ICALEPCS, a small multi-region team has developed a reference design model for a control system for the International Linear Collider as part of the ILC Global Design Effort. The scale and performance parameters of the ILC accelerator require new thinking in regards to control system design. Technical challenges include the large number of accelerator systems to be controlled, the large scale of the accelerator facility, the high degree of automation needed during accelerator operations, and control system equipment requiring 'Five Nines' availability. The R and D path for high availability touches the control system hardware, software, and overall architecture, and extends beyond traditional interfaces into the technical systems. Software considerations for HA include fault detection through exhaustive out-of-band monitoring and automatic state migration to redundant systems, while the telecom industry's emerging ATCA standard - conceived, specified, and designed for High Availability - is being evaluated for suitability for ILC front-end electronics.

396

Fuzzy logic electric vehicle regenerative antiskid braking and traction control system  

Science.gov (United States)

An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control.

Cikanek, Susan R. (Wixom, MI)

1994-01-01

397

Fuzzy logic electric vehicle regenerative antiskid braking and traction control system  

Science.gov (United States)

An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control. 123 figs.

Cikanek, S.R.

1994-10-25

398

MODLP program description: A program for solving linear optimal hydraulic control of groundwater contamination based on MODFLOW simulation. Version 1.0  

International Nuclear Information System (INIS)

MODLP is a computational tool that may help design capture zones for controlling the movement of contaminated groundwater. It creates and solves linear optimization programs that contain constraints on hydraulic head or head differences in a groundwater system. The groundwater domain is represented by USGS MODFLOW groundwater flow simulation model. This document describes the general structure of the computer program, MODLP, the types of constraints that may be imposed, detailed input instructions, interpretation of the output, and the interaction with the MODFLOW simulation kernel