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1

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

1996-04-22

2

Hydraulic loop: practices using open control systems  

International Nuclear Information System (INIS)

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

1998-01-01

3

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)

2002-06-01

4

Robust control of hydraulically operated gimbal system  

International Nuclear Information System (INIS)

A transmitting antenna operated on the naval vessels can be easily excited by exogenous disturbances such as tidal wave and impact. Gimbal system that supports the antenna needs the controller to maintain the robust performance against various modeling uncertainties and disturbance. PI controller, however, cannot guarantee the reasonable robust performance under these kinds of severe conditions. Thus a robust H ? control scheme is recommended to ensure a specified dynamic response under heavy operating conditions. Gimbal system is simplified as two degree of freedom model that ignores coordinate co-relations of each direction and hydraulic system is modelled linearly. The simulation and experimental results of H ? controller proposed in this paper showed the better responses and stability than those of PI controller

2007-05-01

5

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.)

1995-11-01

6

Pressure Control in Hydraulic Power Steering Systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

There is a clear trend in the vehicle industry to implement more safetyrelated functions, where the focus is on active safety systems and today the steering system is also involved. Steering-related active safety functions can only be realised with a steering system that allows electroniccontrol of either the road wheel angle or the torque required to steer the vehicle, called active steering. The high power requirement of heavy vehicles means they must rely on hydraulic power to assist the d...

Dell’amico, Alessandro

2013-01-01

7

Hydraulic system for driving control rods  

International Nuclear Information System (INIS)

Purpose: To enable safety reactor shut down upon occurrence of an abnormal excess pressure in a hydraulic control unit. Constitution: The actuation pressure for a pressure switch that generates a scram signal is set lower than the release pressure set to a pressure release valve. Thus, if the pressure of nitrogen gas in a nitrogen container increases such as upon exposure of the hydraulic control unit to a high temperature, the pressure switch is actuated at first to generate the scram signal and a scram valve is opened to supply water at high pressure to control rod drives under the driving force of the nitrogen gas at high pressure to rapidly insert the control element into the reactor and shut down it. If the pressure of the nitrogen gas still increases after the scram, the pressure release valve is opened to release the nitrogen gas at high temperature to the atmosphere. Since the scram is attained before the actuation of the pressure release valve, safety reactor shut down can be attained and the hydraulic control unit can be protected. (Sekiya, K.)

1980-11-07

8

Hydraulic system of control of a powered support  

Energy Technology Data Exchange (ETDEWEB)

The objective of the invention is to increase reliability of the hydraulic system. This is achieved as follows. The control cavity of the pilot controlled check valve is connected to its input and to the piston-free cavity of the transfer hydraulic cylinder via a check valve, and the output is connected to one of the pressure lines.

Monin, L.M.; Lokhov, Yu.B.

1981-02-10

9

Design of Transputer Controllers for Hydraulic Actuator Systems.  

DEFF Research Database (Denmark)

The paper deals with how transputers can be applied for fast controllers for hydraulic actuator systems. A general transputer-based control systems including a data acquisition transputer subsystem is presented. An application case: development of a mechatronic test facility with a fast hydraulic test robot controlled by a transputer-basec controller is presented. Some experimental path-tracking results with adaptive control algorithms are presented and discussed. The results confirm that transputers have significant advantages for intelligent control of actuator systems and robots for high speed and precision tasks.

Conrad, Finn

1996-01-01

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

International Space Station power module thermal control system hydraulic performance  

Energy Technology Data Exchange (ETDEWEB)

The International Space Station (ISS) uses four photovoltaic power modules (PVMs) to provide electric power for the US On-Orbit Segment. The PVMs consist of photovoltaic arrays (PVAs), orbit replaceable units (ORUs), photovoltaic radiators (PVRs), and a thermal control system (TCS). The PVM TCS function is to maintain selected PVM components within their specified operating ranges. The TCS consists of the pump flow control subassembly (PFCS), piping system, including serpentine tubing for individual component heat exchangers, headers/manifolds, fluid disconnect couplings (FQDCs), and radiator (PVR). This paper describes the major design requirements for the TCS and the results of the system hydraulic performance predictions in regard to these requirements and system component sizing. The system performance assessments were conducted using the PVM TCS fluid network hydraulic model developed for predicting system/component pressure losses and flow distribution. Hardy-Cross method of iteration was used to model the fluid network configuration. Assessments of the system hydraulic performance were conducted based on an evaluation of uncertainties associated with the manufacturing and design tolerances. Based on results of the analysis, it was concluded that all design requirements regarding system performance could be met. The hydraulic performance range, enveloping possible system operating parameter variations was determined.

Goldberg, V. [Boeing North American, Inc., Canoga Park, CA (United States). Rocketdyne Div.

1997-12-31

12

Seismic analysis of hydraulic control rod driving system  

International Nuclear Information System (INIS)

A simplified mathematical model was developed for the Hydraulic Control Rod Driving System (HCRDS) of a 200 MW nuclear heating reactor, which incorporated the design of its chamfer-hole step cylinder, to analyze its seismic response characteristics. The control rod motion was analyzed for different sine-wave vibration loadings on platform vibrator. The vibration frequency domain and the minimum acceleration amplitude of the control rod needed to cause the control rod to step to its next setting were compared with the design acceleration amplitude spectrum. The system design was found to be safety within the calculated limits. The safety margin increased with increasing frequency. (author)

2002-12-01

13

High power hydraulic speed control system of a butterfly survey  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Volume of work is 51 pages and contains 23 pictures. References inventory consists of 36 literary sources. The main aim of the investigation - to analyze the hydraulic cylinder shaft speed characteristics of dependency, changing the working pressure of hydraulic system and droseliavimo character. Master's thesis consists of three parts: an overview of sources of information, an overview of theoretical studies and experimental studies. Review of information sources describe butterfly hydraulic...

2010-01-01

14

Fuzzy Immune PID Control of Hydraulic System Based on PSO Algorithm  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper takes the permanent magnet servo motor-driven hydraulic system as the research object. The hydraulic system power source uses servo motor instead of the original asynchronous motor, becoming a new energy-saving, fast response, and easy to realize closed-loop control hydraulic power systems. Aiming at variability of the load for the hydraulic system, immune algorithm is introduced to incremental P...

Ma Yu; Gu Lichen

2013-01-01

15

Modification Of Control System For Flow On Hydraulic Rabbit System Facility  

International Nuclear Information System (INIS)

Had been modification control system on the hydraulic rabbit system facility is installed at floor +8 m in reactor building GA. Siwabessy. On the hydraulic rabbit system is used water for media transfer and media cooling from hot cell to irradiation position or from irradiation position to hot cell. Flow water to sent capsule target about 55 liters/minute. Flow meter type RS No. 185-9926 is installed in hydraulic rabbit system. The flow meters have specification : flow rate 5 to 100 liters/minute, maximum working pressure 10 bar, temperature range 5 to 60 "oC and viscosity range 10 to 200 centistokes. The flow meter is installed on the pipe line upper pump of hydraulic rabbit system facility in room no.0626 floor +8 meter reactor building. After the flow meter installed, flow rate on the hydraulic rabbit system can measure direct, flow rate can be adjusted and result same as on the monitor

2001-02-01

16

Fuzzy Immune PID Control of Hydraulic System Based on PSO Algorithm  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper takes the permanent magnet servo motor-driven hydraulic system as the research object. The hydraulic system power source uses servo motor instead of the original asynchronous motor, becoming a new energy-saving, fast response, and easy to realize closed-loop control hydraulic power systems. Aiming at variability o...

Ma Yu; Gu Lichen

2013-01-01

17

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 s...

Huaizhong Chen

2012-01-01

18

Safety analysis of hydraulic control rod drive system for nuclear reactor.  

Science.gov (United States)

A new kind of hydraulic control rod drive system which is used for water cooling reactor is introduced. The safety and reliability of the system under various working conditions are analyzed. The safety property at the break of hydraulic circuit pipes of ...

G. Chen Y. Wu Z. Gao F. Zhang J. Yang

1992-01-01

19

Modeling and Controller Design of an Electro-Hydraulic Actuator System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 Identific...

Rahmat, M. F.; Rozali, S. M.; Wahab, N. A.; Zulfatman; Kamaruzaman Jusoff

2010-01-01

20

Study on Control Strategy of Electro-Hydraulic Servo Loading System  

Directory of Open Access Journals (Sweden)

Full Text Available Since extraneous torque is the key factor to affect the accuracy of electro-hydraulic servo loading system, the forming mechanism of extraneous torque was discussed in this work. And then several design methods of loading system controller based on modern control theory were introduced, such as internal model control, Cerebella model articulation control and adaptive backstepping control.

Ju Tian

2013-09-01

 
 
 
 
21

Servo-pump hydraulic control system performance and evaluation for CVT pressure and ratio control  

Energy Technology Data Exchange (ETDEWEB)

Fluid pumping losses are one of the major sources of torque loss in modern continuously variable transmissions (CVTs) due to the high pressures and flow rates required in the hydraulic control system. To reduce the magnitude of these losses, researchers at UC Davis have developed a servo-pump control system for CVTs designed for improved pressure and ratio controllability with minimal power consumption. This paper includes a description of the control system concept and configuration as well as an evaluation of the power draw of the system. The results of vehicle testing show that the servo-pump CVT control system reduces the control power required by more than 83%. Vehicle testing and simulation provide an estimate of the fuel economy gain that can be achieved using the servo-pump CVT control system in a hybrid-electric vehicle (HEV) application. (orig.)

Bradley, T.H.; Frank, A.A.

2002-07-01

22

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

23

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

24

Experimental study of hydraulic driving system of control rod not engendering rod ejection accident  

International Nuclear Information System (INIS)

The hydraulic driving system of control rod is a new controlling-equipment in nuclear reactor. Its drive assembly is hydraulic step cylinder. The cylinder can be installed in the pressure vessel and its inner tube is fixed on the bottom block of core. By the experiment for experimental loop (including pressure vessel, hydraulic step cylinder, heater, pump and another devices) and measuring system, the rod position is measured and observed when the pressure vessel loses pressure under high temperature and high pressure. A lot of experimental data and observed results are obtained. The results indicate: The hydraulic driving system of control rod can not engender rod ejection accident when the pressure vessel loses pressure. So, this system has inherent safety feature of not engendering rod ejection

1998-06-01

25

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

26

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

Energy Technology Data Exchange (ETDEWEB)

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

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

28

Power control units with secondary controlled hydraulic motors - a new concept for application in aircraft high lift systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Today?s high lift systems of civil transport aircraft are driven by Power Control Units using valve controlled constant displacement hydraulic motors. This concept leads to complex valve blocks, attended by high power losses to realise discrete speed control, positioning and pressure maintaining functionality. The concept of secondary controlled hydraulic motors with variable displacement offers reduction in flow consumption without pressure losses and decreases the complexity of the val...

Biedermann, Olaf; Geerling, Gerhard

1998-01-01

29

Hydraulic control of existing district heating systems. Hydraulische Einregulierung in bestehenden Fernheizungssystemen  

Energy Technology Data Exchange (ETDEWEB)

Hydraulic control ensures that the required optimum room climate is available. Illness can be appreciably reduced by this. The energy consumption is reduced, directly by reducing the average room temperature in the heating system and indirectly by providing the right operating conditions for the control system. The power of the circulating pumps and the electrical energy required for operation can be reduced. (orig.).

Exner, G. (Ingenieurbuero E. und E., Zepernick (Germany))

1992-06-01

30

System and method for controlling engine knock using electro-hydraulic valve actuation  

Science.gov (United States)

A control system for an engine includes a knock control module and a valve control module. The knock control module adjusts a period that one or more of an intake valve and an exhaust valve of a cylinder are open based on engine knock corresponding to the cylinder. The valve control module, based on the adjusted period, controls the one or more of the intake valve and the exhaust valve using one or more hydraulic actuators.

Brennan, Daniel G

2013-12-10

31

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

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

The study on measures to improve the reliability of the hydraulic systems of shearers - study of measures to control the oil contamination of hydraulic systems  

Energy Technology Data Exchange (ETDEWEB)

The authors indicate that the failure rate of hydraulic systems of shearers can drop greatly, its reliability and service life can be increased by the use of a field oil contamination analyser and filter device to control the oil contamination of the hydraulic systems of shearers. Theoretical analysis and experimental provement of silting-theory contamination analyser are carried out. The filter effect of portable hydraulic driving oil-filter model YLJ-21 is examined in laboratory and field experiment. From January to August 1992, on-site experimental research using a silting-theory contamination analyser and oil-filter model YLJ-21 to control the oil contamination was carried out in the Daton Coal Mining Bureau. 3 refs., 3 figs., 6 tabs.

Xu, L.; Gao, X.; Du, C.; Song, Q.; Wu, Y.; Wu, X. [Central Coal Mining Research Institute (China)

1996-12-31

34

Kinematic study on hydraulic control rod driving system for HR-200 heating reactor  

International Nuclear Information System (INIS)

In order to analyse the performance on the Hydraulic Control Rod Driving System for HR-200 Heating Reactor and the factors affecting its performance and some possible improvements on this system, a method is presented, that is, at first to linearize the two-order nonlinear differential equations by neglecting the multi-powered small quantities or segmenting, then to solve the linearized differential equations by using Laplace transformation. The motion rule of the control rod near the balance position is found and a simple numerical method to calculate the rod's movement on any position is proposed. The theoretical analyses and comparisons with experimental results are conducted. Both the theoretical analyses and the experiments show that with certain structural improvements and parameters change, this Hydraulic Control Rod Driving System will be able to work properly on HR-200. The main factors affecting the system's performance are analyzed and some reasonable improving methods are proposed

1991-01-01

35

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

1994-01-01

36

Vehicle hydraulic actuating system  

Energy Technology Data Exchange (ETDEWEB)

A hydraulic actuating system for a mechanical element is described comprising: a single-acting master cylinder having a ram and at least one cylinder port at a first elevation, the master cylinder ram being biased in a first direction; acturator means for moving the master cylinder ram in a second direction opposite the first direction and generating fluid pressure in the master cylinder; a single-acting slave cylinder with at least one cylinder port at a second lower elevation, the slave cylinder having fluid communication with the master cylinder and the slave cylinder controlling the mechanical element; and a fluid reservoir having selective fluid communication with the cylinder port of the first elevation for bleeding the hydraulic actuating system.

Tordoff, R.L.

1988-01-05

37

Electro-hydraulic system developed in Poland for longwall support control  

Energy Technology Data Exchange (ETDEWEB)

Describes the ESTER and ASTER support control systems developed in Poland. The ESTER system is a close-range control system with initiated automatic sequence of adding support sets. It is suitable for all types of longwall support. The ASTER system is a remote control system with programmable functional parameters. It provides the possibility of remote and close-range control from consoles or by push-buttons arranged directly on the electro-hydraulic blocks. Remote control enables the following functions to be controlled from a console: roof-bar lowering, adding a set to the conveyor, setting it to load and conveyor advancing. Control of slide-roof bars, slewable cowls and working face shields is also possible. Problems of crew training, implementation, exploitation and servicing are discussed.

Sikora, W.; Sobczyk, J. (Centrum Elektryfikacji i Automatyzacji Gornictwa EMAG (Poland))

1992-07-01

38

Cascade Controller Including Back-stepping for Hydraulic-Mechanical Systems  

DEFF Research Database (Denmark)

Development of a cascade controller structure including adaptive backstepping for a nonlinear hydraulic-mechanical system is considered in this paper where a dynamic friction (LuGre) model is included to obtain the necessary accuracy. The paper compares the performance of two variants of an adaptive backstepping tracking controller with earlier results. The new control architecture is analysed and enhanced tracking performance is demonstrated when including the extended friction model. The complexity of the backstepping procedure is significantly reduced due to the cascade structure. Hence, the proposed control structure is better suited to real-time implementation. © 2012 IFAC.

Choux, Martin; Hovland, Geir

2012-01-01

39

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

40

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 proposed control scheme. It is shown from the experimental results that the proposed controller offers several advantages such as fast response, good disturbance rejection capability, good velocity tracking capability and so forth. It is also revealed from simulation results that the proposed control strategy is valid for the EHVSS.

Shao Jiang Wang

2012-01-01

 
 
 
 
41

Deterministic Control Strategy for a Hybrid Hydraulic System with Intermediate Pressure Line  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The paper introduces a new hydraulic system for mobile machines based on a constant pressure system with the aim to increase the efficiency of actuation of hydraulic cylinders. Using a third pressure level located between high pressure and tank pressure called intermediate pressure the system enables additional pressure potentials from high pressure to intermediate pressure and from intermediate pressure to tank pressure. This reduces throttle losses at hydraulic cylinders when driven at low ...

2012-01-01

42

Dynamic modelling of pressure control system of a 500 MWe PHWR power plant thermal hydraulics aspects  

International Nuclear Information System (INIS)

A computer code for the dynamic analysis of the proposed 500 MWe Pressurised Heavy Water Reactor is being developed. One of the modules of this code deals with the primary heat transport system pressure control. A thermal hydraulic model of the pressure control system has been developed. This model includes the following : reactor coolant loop, primary circulating pump, Core heat transfer, Feed/bleed with Bleed Condenser and pressure controller. Analysis has been carried out for transients like change in reactor power, leakage from the primary heat transport system and malfunctioning of control system. The mathematical model is presented in the paper along with the results obtained for some of the transients analysed. (author). 6 refs., 6 figs

1992-01-01

43

Experiment study on rod ejection accident of hydraulic control rod driving system  

International Nuclear Information System (INIS)

The rod ejection experiment has been done in the 1:1 experiment loop of the hydraulic control rod driving system (HCRDS) of the 200 MW nuclear heating reactor (NHR-200). The result indicated that under different experiment conditions, the control rod was not ejected when the pressure vessel of the loop lost pressure. Based on the depressurization accident analysis of the NHR-200, performed at the Institute of Nuclear Energy Technology (INET), Tsinghua University, the depressurization rate of experiment is much higher than that of analysis. Thus, the HCRDS has inherent safety and no hidden trouble of rod ejection when the depressurization accident happens. (author)

2001-12-01

44

Design, analysis and control of hydraulic soft yaw system for 5MW 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 wereby dampen the loads to the system. This paper presents work done on dampening of these loads by active control of a hydraulic yaw system. The control is based on a non-linear and linear model derived based on a concept yaw system for the NREL 5MW wind turbine. The control strategies show a reduction in pressure pulsations under load and it is concluded that the strategie including high-pass pressure feedback is the most suitable for this application.

Stubkier, Søren; Pedersen, Henrik C.

2012-01-01

45

High Precision Position Control of Electro-Hydraulic Servo System Based on Feed-Forward Compensation  

Directory of Open Access Journals (Sweden)

Full Text Available The study is focused on an electro-hydraulic servo system which is a position control system. It is a non-minimum phase system when it was discretized with a certain sample time. To improve its tracking performance and extend its bandwidth, based on invariance principle, feed-forward compensation is developed by pole-zero placement theory for the system. The task is accomplished by transforming instable zero of the system into pole of the fitted closed-loop transfer function, forming the zero of feed-forward compensator and completing the compensation of the instable zero for the closed-loop system. The simulation and experimental results show the validity of the analytical results and the ability of the proposed algorithm to efficiently improve the system tracking performance and greatly extend system bandwidth.

Yao Jian-jun

2012-02-01

46

Decoupling Control Research on Test System of Hydraulic Drive Unit of Quadruped Robot Based on Diagonal Matrix Method  

Directory of Open Access Journals (Sweden)

Full Text Available The mathematical model of hydraulic drive unit of quadruped robot was built in this paper. According to the coupling characteristics between position control system and force control system, the decoupling control strategy was realized based on diagonal matrix method in AMESim?. The results of simulation show that using diagonal matrix method can achieve the decoupling control effectively and it can achieve the decoupling control more effectively with the method of not offset pole-zero in the S coordinate. This research can provide theoretical basis for the application of test system of hydraulic drive unit.

Lingxiao Quan

2013-08-01

47

Control strategy of hydraulic/electric synergy system in heavy hybrid vehicles  

International Nuclear Information System (INIS)

Energy consumption and exhaust emissions of hybrid vehicles strongly depend on the energy storage source and the applied control strategy. Heavy vehicles have the characteristics of frequent starts/stops and significant amounts of braking energy, which needs to find a more efficient way to store and use the high power flow. A novel parallel hybrid vehicles configuration consisting of hydraulic/electric synergy system is proposed to overcome the existing drawbacks of single energy storage source in heavy hybrid vehicles. A control strategy combining a logic threshold approach and key parameters optimization algorithm is developed to achieve acceptable vehicle performance while simultaneously maximizing engine fuel economy and maintaining the battery state of charge in its rational operation range at all times. The experimental and simulation results illustrate the potential of the proposed control strategy in terms of fuel economy and in keeping the deviations of SOC at high efficiency range.

2011-01-01

48

Hydraulic Yaw System  

DEFF Research Database (Denmark)

As wind turbines increase in size, combined with increased lifetime demands, new methods for load reduction needs to be examined. One method is to make the yaw system of the turbine soft/flexible and hereby dampen the loads to the system, which is the focus of the current paper. By utilizing the HAWC2 aeroelastic code and an extended model of the NREL 5MW turbine combined with a simplified linear model of the turbine, the parameters of the soft yaw system are optimized to reduce loading in critical components. Results shows that a significant reduction in fatigue and extreme loads to the yaw system and rotor shaft when utilizing the soft yaw drive concept compared to the original stiff yaw system. The physical demands of the hydraulic yaw system are furthermore examined for a life time of 20 years. Based on the extrapolated loads, the duty cycles show that it is possible to construct a hydraulic soft yaw system, which is able to reduce the loads on the wind turbine significantly. A full scale hydraulic yaw test rig is available for experiments and tests. The test rig is presented as well as the system schematics of the hydraulic yaw system.

Stubkier, Søren; Pedersen, Henrik C.

49

Control system for a direct-coupling mechanism in hydraulic power transmission means of a transmission for automotive vehicles  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a transmission for an automotive vehicle, including a hydraulic power transmission means having an input member and an output member, and a direct-coupling mechanism having a hydraulically operating portion and arranged between the input and output members. The direct-coupling mechanism is operable to mechanically engage the input and output members with each other with an engaging force corresponding to the magnitude of an operating fluid pressure applied to the hydraulically operating portion. An operating fluid source is included and operating fluid pressure regulating means is arranged between the operating fluid source and the hydraulically operating portion of the direct-coupling mechanism for regulating the operating fluid pressure to be applied to the hydraulically operating portion. A control system is described for controlling the direct-coupling mechanism, comprising: vehicle speed sensor means for detecting the speed of the vehicle; slip sensor means for detecting the value of a parameter indicative of an amount of relative slip between the input and output members; and control means which controls the operating fluid pressure regulating means to vary the magnitude of the operating fluid pressure so that the parameter falls within a predetermined range, when the vehicle speed detected by the vehicle speed sensor means falls between a first predetermined value and a second predetermined value larger than the first predetermined value and at the same time the value of the parameter detected by the slip sensor means is outside the predetermined range.

Aoki, T.; Miyake, J.; Nishikawa, M.

1987-03-24

50

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...

2009-01-01

51

Trends in Modelling, Simulation and Design of Water Hydraulic Systems â?? 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. Todayâ??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

52

Regeneration system for a hydraulic intensifier unit  

Energy Technology Data Exchange (ETDEWEB)

A hydraulic intensifier unit is described, which eliminates the necessity for physically replacing the pistons and other parts of the rams in order to achieve either a high fluid flow pumping rate or a relatively higher pressure on the fluid being pumped into the well. Through a control valve and conduit arrangement, the system extracts hydraulic fluid from the return face side of the pistons of the hydraulic cylinder motors during the power stroke, and pumps this fluid into the working face side of the hydraulic cylinder motors along with the main source of hydraulic fluid. This decreases the amount of fluid required from the source in order to move the pistons from their retracted positions to their extended positions and thus increases the cycling rate of the intensifier unit. The regeneration system optionally may be cut out through operation of the control valve, and the hydraulic fluid dumped into a tank so that maximum pressure can be achieved. 8 claims.

Hall, R.W.; Sonnenberg, S.; Mahal, H.S.

1983-06-28

53

Improvement of diesel engine performance by hydraulically powered electronic control (mechatronics) system. Hakuyo diesel kikan no mechatronics system ni yoru seino kojo  

Energy Technology Data Exchange (ETDEWEB)

This paper describes new hydraulically-actuated mechanisms for both fuel injection and inlet/exhaust valve operation of diesel engines through solenoid valves, which obviate the conventional cam-driven system. These mechanisms were integrated with an electronic control unit also developed in this study and they were mounted as a mechatronics system'' on a power-increased single-cylinder engine. This mechatronics system was mainly composed of an injection control. boost and accumulation component, an inlet and exhaust valve control component, a solenoid valve, an electronic control equipment, a hydraulic power unit, and a maneuvering unit. The verification test was carried out for the improvement of diesel engine performance by the hydraulically powered mechatronics system. As a result, it was proved not only that these mechanisms provide stable operating characteristics over a wide range of conditions, but also that the electronic control system allows accurate, smooth response. 3 refs., 23 figs., 2 tabs.

Sonoda, K.; Nakamura, Y.; Kajima, T.; Sato, S.; Fujii, T.; Tobe, Y. (Kawasaki Heavy Industries, Ltd., Tokyo (Japan))

1992-07-20

54

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

55

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

56

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

57

Development of a quality management system for borehole investigations. (1) Quality assurance and quality control methodology for hydraulic packer testing  

International Nuclear Information System (INIS)

A quality assurance and quality control (QA/QC) system for the hydraulic packer tests has been established based on the surface-based investigations at JAEA's underground research laboratories in Mizunami and Horonobe. The established QA/QC system covers field investigations (data acquisition) and data analysis. For the field investigations, the adopted procedure is selection of a test section based on a detail fluid logging and checking with tally list, followed by inspection of test tools such as pressure transducers and shut-in valves, etc., test method selection using a 'sequential hydraulic test' for deciding appropriate method, and finally data quality confirmation by pressure changes and derivatives on a log-log plots during testing. Test event logs should also be described during testing for traceability. For the test data analysis, a quick analysis for rough estimation of hydraulic parameters, and a detailed analysis using type curve and/or numerical analyses are conducted stepwise. The established QA/QC system has been applied to the recent borehole investigations and its efficiency has been confirmed. (author)

2010-10-03

58

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

59

Indirect Dynamic Recurrent Fuzzy Neural Network and Its Application in Identification and Control of Electro-Hydraulic Servo System  

Science.gov (United States)

As the affine nonlinear system is characterized by differential relations between the states, an adaptive dynamic recurrent fuzzy neural network (ADRFNN) taking only the measurable states as its inputs and describing the system’s inner dynamic relation by its feedback matrix is proposed to evaluate the unknown dynamic nonlinear functions including nonlinearity, parameter uncertainty and load disturbance. The adaptive laws of the adjustable parameters and the evaluation errors’ bounds of ADRFNN are formulated based on lyapunov stability theory. Also the stable indirect ADRFNN controller (ADRFNNC) with gain adaptive VSC (GAVSC) for the estimation errors by ADRFNN and the load disturbance are synthesized. It can overcome the shortcomings of the structural expansion caused by larger number of inputs in traditional adaptive fuzzy neural networks (TAFNN) taking all states as its inputs. The application in electro-hydraulic position tracking system (EHPTS) shows that it has an advantage over the TAFNN controller (TAFNNC) in steady characteristics of system. Furthermore, the chattering of the system’s control effort is weakened and so the system possesses greater robustness.

Huang, Yuan-Feng; Zhang, You-Wang; Min, Peng

60

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

1994-09-14

 
 
 
 
61

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

62

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

63

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)

2013-01-01

64

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

65

Improved feedwater control through microprocessor based reactor feedpump turbine electro-hydraulic controls  

International Nuclear Information System (INIS)

Matched response between the feedwater control system and the reactor feedpump turbine (RFPT) control system enhances plant performance and cushions the interface between the turbine generator and feedwater systems. Digital control techniques, applied through the latest microprocessor technology, provide the flexibility to match characteristics of these systems. Most older systems use mechanical hydraulic governors utilizing a hydraulic supply common with the bearing lubrication system. Along with inherently slow dynamic responses, these systems are subject to contamination related control problems and associated high levels of maintenance. A retrofittable system is described that combines a conversion to a high pressure electro-hydraulic fluid system with microprocessor based control technology for improved feedwater system performance

1986-09-01

66

A Robust Adaptive Hydraulic Power Generation System for Jet Engines  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The paper presents an innovative hydraulic power generation system able to enhance performance, reliability and survivability of hydraulic systems used in military jet engines, as well as to allow a valuable power saving. This is obtained by a hydraulic power generation system architecture that uses variable pressure, smart control, emergency power source and suitable health management procedures. A key issue is to obtain all these functions while reducing to a minimum the number of additiona...

Ronco, Pierantonio; Sorli, Massimo; Mornacchi, Andrea; Jacazio, Giovanni

2013-01-01

67

Hydraulic Yaw System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

As wind turbines increase in size, combined with increased lifetime demands, new methods for load reduction needs to be examined. One method is to make the yaw system of the turbine soft/flexible and hereby dampen the loads to the system, which is the focus of the current paper. By utilizing the HAWC2 aeroelastic code and an extended model of the NREL 5MW turbine combined with a simplified linear model of the turbine, the parameters of the soft yaw system are optimized to reduce loading in cr...

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

2012-01-01

68

Control system for the feed of pressurized fluid in a hydraulic circuit as a function of the state of the locking or unlocking of two mechanical organs  

International Nuclear Information System (INIS)

The control system comprises two hydraulic cylinders of which rods are integral with the mechanical organs. The piston of the first cylinder separates the chamber of this one in two parts. The piston of the second cylinder separates its chamber in three parts. The inlet chamber of the two cylinders are connected to pressurized fluid feed pipes, and the outlet chambers to a depressurization pipe. According to the position of the piston depending itself on the state of locking or unlocking of the rods, an interconnection pipe and a feed pipe of the pressurized fluid hydraulic circuit communicate with a chamber or another one. The feed of the hydraulic circuit is possible only the two rods are unlocked. The invention applies more particularly to the feed of the control circuit of an emergency seal of the primary pump of a pressurized water nuclear reactor

1983-12-16

69

Plug & Play Control of Hydraulic Networks  

DEFF Research Database (Denmark)

Typically, control systems are designedwith little or no consideration for possible changes in the structure of the system process to be controlled. In classic control design, a monolithic approach is taken where structural changes in the system process require the development of a new mathematical model of the system and a subsequent redesign of the control system. This process can be expensive and time consuming. Therefore, an attractive alternative is to design the control system such that it automatically reconfigures whenever structural changes occur. This is the aim of the Plug & Play Process Control research program, which the work presented here is a part of. An industrial case study involving a large-scale hydraulic network with non-linear dynamics is studied. The hydraulic network underlies a district heating system, which provides heating water to a number of end-users in a city district. The case study considers a novel approach to the design of district heating systems in which the diameter of the pipes used in the system is reduced in order to reduce the heat losses in the system, thereby making it profitable to provide district heating to areas with low energy demands. The new structure has the additional benefit that structural changes such as the addition or removal of end-users are easily implementable. In this work, the problem of controlling the pressure drop at the end-users to a constant reference value is considered. This is done by the use of pumps located both at the end-users and at designated places across the network. The control architecture which is used consists of a set of decentralized linear control actions. The control actions use only the measurements obtained locally at each end-user. Both proportional and proportional-integral control actions are considered. Some of the work considers control actions which are constrained to non-negative values only. This is due to the fact that the actuators in this type of system typically consist of centrifugal pumps which are only able to deliver non-negative actuation. Other parts of the work consider control actions which have been quantized. That is, they are restricted to piecewise constant signals taking value in a bounded set. This is done in order to facilitate sending the control signals across a finite bandwidth communication network. This is necessary since the actuators in the system are geographically separated from the logic circuitry implementing the control actions. The results presented here consist of a series of global stability results of the closedloop system using the control actions described above. The stability analysis is complicated by the non-linearities present in the system process. Specifically, global practical output regulation can be shown when using proportional control actions, while global asymptotical output regulation can be shown when using proportional-integral control actions. Since the results are global in the state space, it is concluded that the closed-loop system maintains its stability properties when structural changes are implemented.

Jensen, Tom Nørgaard

2012-01-01

70

Saving Energy in Construction Machinery using Displacement Control Hydraulics : Concept Realization and Validation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the sector of mobile hydraulics, valve controlled systems are predominant. In these systems the load force and speed are adjusted by control valves. In machines where multiple drives are used in parallel at extremely varying loads the energy efficiency of such systems is often compromised over large working regions. Most valve controlled systems also lack the possibility to recuperate potential energy. A different category of hydraulic systems, called displacement controlled hydraulics are...

2008-01-01

71

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

Energy Technology Data Exchange (ETDEWEB)

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

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

1996-09-01

72

Hydraulic control apparatus for drill bailer and ordinary bailer  

Energy Technology Data Exchange (ETDEWEB)

This hydraulic control apparatus for all kinds of bailers consists of a cable attached to the drilling rig which controls a hydraulic jack. This jack, in turn, controls a second hydraulic jack. The piston of the second jack, under the control of the first jack, controls the opening and closing of the jaws of the bailer.

Ricouard, H.

1983-07-23

73

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

74

State control for hydraulic power plants  

Energy Technology Data Exchange (ETDEWEB)

The level control in hydraulic power plants on rivers is of great importance for their automation. In this paper, a new modelling method of the flow dynamics is presented. The obtained model is especially suitable for small friction losses situations where the level waves phenomena cannot be neglected. This model is used to design the state-observer control. Finally, a practical case is presented. (author)

Lahlou, Mouncif [Swiss Federal Inst. of Technology, Lausanne (Switzerland). Industrial Electronics Lab.

1996-12-31

75

Regeneration system for a hydraulic intensifier unit  

Energy Technology Data Exchange (ETDEWEB)

A hydraulic intensifier for oil well fracturing and/or erosion drilling, having a pair of intensifier units including a pair of sequentially operated reciprocating ram assemblies powered by hydraulic cylinder motors which are operated to maintain a substantially uniform output fluid pressure from the intensifier unit. Each cylinder motor is supplied from a main source of hydraulic fluid under high pressure which operates on the working faces of the pistons of the cylinder motors. Hydraulic fluid is also supplied to the return face side of each piston in the hydraulic cylinder motor. The return face side of the pistons have a smaller operative area than the working face sides and each can be connected to the main source of supply of hydraulic fluid to the working faces so that as the pistons are driven to their extended positions by application of hydraulic pressure to the working face, the fluid on the return face side can be expelled from the cylinder motors and returned to the working face side to either reduce the fluid flow from the source while maintaining the same cycling rate or maintaining the same flow from the source by increasing the cycling rate and thus increasing the total volume flow. An adjustable pressure relief valve is provided to permit control of the pressure in the well to a maximum desired limit by relieving pressure of the infeed fluid to the hydraulic cylinder motors.

Hall, R. W.; Mahal, H. S.; Sonnenberg, S.

1985-11-26

76

In-casing hydraulic jack system  

Energy Technology Data Exchange (ETDEWEB)

An in-casing hydraulic jack system for operating well bottom pumping units via a sucker rod string and polish rod is described, comprising a jack unit having a hydraulic cylinder with top and bottom ends and a piston positioned for reciprocation within the hydraulic cylinder, mounting means connected to the jack unit for suspending the jack unit fully within a well casing, sealing means carried by the jack unit for producing a seal between the jack unit and the interior of the well casing, connecting means at the bottom end of the hydraulic cylinder for connecting the jack unit to a top end of a well fluid delivery tubing, attaching means for attaching a top end of a polish rod to the piston of the jack unit so as to be displaceable in conjunction therewith and access means disposed above the jack unit for enabling insertion and removal of the polish rod while the jack unit is suspended in the well casing. There are also hydraulic fluid supply means connected to the hydraulic cylinder for producing reciprocation of the piston within the cylinder by delivery of hydraulic fluid to the hydraulic cylinder in a manner to as to produce an upward stroking of the polish rod, and discharge means in the jack unit for enabling well fluid delivered by the well fluid delivery tubing to bypass the sealing means so as to be discharged from the well casing at a location above the seal means.

Henderson, T.

1988-05-24

77

Instrumentation System for Massive Hydraulic Fracture Mapping.  

Science.gov (United States)

The measurement of induced surface potentials has been used in a research effort to map the orientation of fractures created by massive hydraulic fracturing. A first generation measurement system has been developed via field testing that has successfully ...

L. J. Keck R. W. Seavey

1977-01-01

78

Analysis of buffering process of control rod hydraulic absorber  

International Nuclear Information System (INIS)

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

2011-10-24

79

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)

1982-01-01

80

High speed on/off valve control hydraulic propeller  

Science.gov (United States)

The work-class remotely-operated-underwater-vehicles (ROVs) are mainly driven by hydraulic propulsion system, and the effeciency of hydraulic propulsion system is an important performance index of ROVs. However, the efficiency of traditional hydraulic propulsion system controlled by throttle valves is too low. Therefore, in this paper, for small and medium ROVs, a novel propulsion system with higher efficiency based on high speed on/off valve control hydraulic propeller is proposed. To solve the conflict between large flow rate and high frequency response performance, a two-stage high speed on/off valve-motor unit with large flow rate and high response speed simultaneously is developed. Through theoretical analysis, an effective fluctuation control method and a novel pulse-width-pulse-frequency-modulation (PWPFM) are introduced to solve the conflict among inherently fluctuation, valve dynamic performance and system efficiency. A simulation model is established to evaluate the system performance. To prove the advantage of system in energy saving, and test the dynamic control performance of high speed on/off valve control propeller, a test setup is developed and a series of comparative experiments is completed. The smimulation and experiment results show that the two-stage high speed on/off valve has an excellent dynamic response performance, and can be used to realize high accuracy speed control. The experiment results prove that the new propulsion system has much more advantages than the traditional throttle speed regulation system in energy saving. The lowest efficiency is more than 40%. The application results on a ROV indicate that the high speed on/off valve control propeller system has good dynamic and steady-state control performances. Its transient time is only about 1 s-1.5 s, and steady-state error is less than 5%. Meanwhile, the speed fluctuation is small, and the smooth propeller speed control effect is obtained. On the premise of good propeller speed control performance, the proposed high speed on/off valve control propeller can improve the effeciency of ROV propulsion system significantly, and provides another attractive ROV propulsion system choice for engineers.

Zhu, Kangwu; Gu, Linyi; Chen, Yuanjie; Li, Wei

2012-05-01

 
 
 
 
81

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

82

Hydraulic accumulator-motor-generator energy regeneration system for a hybrid hydraulic excavator  

Science.gov (United States)

Though the traditional energy regeneration system(ERS) which used a hydraulic motor and a generator in hybrid excavators can regenerate part of the energy, the power of the motor and the generator should be larger and the time for regenerating energy is so short. At first, the structure of new ERS that combines the advantages of an electric and hydraulic accumulator is analyzed. The energy can be converted into both the electric energy and the hydraulic energy at the lowering of the boom and the generator can still works when the boom stops going down. Then, a method how to set the working pressure of the hydraulic accumulator is proposed. To avoid the excess loss, extra noise and shock pressure, a two-level pressure threshold method that the generator starts to work at the rising edge of the high pressure threshold and stops working at the falling edge of the low pressure threshold is presented to characterize the working mode of the generator. The control strategies on how to control the boom velocity at the lowering of the boom and how to improve the recovery efficiency when the boom stops going down are presented. The test bench of hybrid excavator with ERS is constructed, with which the studies on the influences of ERS on energy conversion efficiency and control performance are carried out. Experimental results show that the proposed ERS features better speed control performance of the boom than traditional ERS. It is also observed that an estimated 45% of the total potential energy could be regenerated at the lowering of the boom in the proposed ERS, and the power level of the generator and the hydraulic motor could be reduced by 60%. Hence, the proposed ERS has obvious advantages over the traditional ERS on the improvement of energy regeneration time, energy efficiency, control performance and economy.

Lin, Tianliang; Wang, Qingfeng

2012-11-01

83

Some aspects of the design of hydraulic system for hydraulically operated truck crane  

Energy Technology Data Exchange (ETDEWEB)

The truck crane/lorry loader is a self-propelled boom crane to move light loads both vertically and horizontally. Operator ease and comfort is always an important factor for improved productivity and efficiency and may be obtained to a great extent by incorporation of hydraulic system. Manufacturers and users of the truck crane are, therefore, presently inclined towards the hydraulically operated one. In this paper, the principle of hydraulic system/circuit design required for hydraulically operated truck crane is discussed.

Biswas, D.K. (National Metallurgical Lab., Jamshedpur (India))

1990-01-01

84

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

85

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

DEFF Research Database (Denmark)

Mobile hydraulics is in a transition phase, where electronic sensors and digital signal processors are starting to become standard on a high number of machines, hereby replacing hydraulic pilot lines and oering new possibilities with regard to both control and feasibility. For controlling some of the existing hydraulic components there are, however, still a need for being able to generate a hydraulic pilot pressure, as e.g. almost all open-circuit pumps are hydraulically controlled. The focus of the current paper is therefore on the analysis and controller design an electro-hydraulic servo pressure regulator, which generates a hydraulic LS-pressure based on an electrical reference, hereby synergistically integrating knowledge from all parts of the mechatronics area. The servo pressure regulator is used to generate the LS-signal for a variable displacement pump, and the paper rst presents the considered system and an experimentally veried model of this. A linearized model is then presented, which comprisethe basis for a stability and sensitivity analysis of the system. Based on the results of the analysis, a control strategy is designed in combination with optimisation of the mechanical design to generate a controlled leakage  ow that aids in stabilising the system. The robustness of the system is then discussed in relation to dierent pilot line volumes and pump dynamics. Finally experimental results are presented, where the performance is compared to that of a similar hydraulic reference system, which has been the basis for the specification of performance requirements.

Pedersen, Henrik C.; Andersen, Torben Ole

2009-01-01

86

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

1995-05-21

87

Breaker system for hydraulic fracturing fluids  

Energy Technology Data Exchange (ETDEWEB)

Aqueous compositions are described which have properties making them suitable for use as hydraulic fracturing fluids. These compositions comprise (1) an uncrosslinked aqueous polysaccharide solution, and (2) a 4,4'-thiodiphenol. Ingredient (2) acts as a breaker and causes the composition to lose viscosity at a controlled rate. 10 claims.

Kucera, C.H.; Connell, R.B.

1983-05-03

88

A new generation drilling rig: hydraulically powered and computer controlled  

Energy Technology Data Exchange (ETDEWEB)

Development, testing and operation of a new generation of hydraulically powered and computer controlled drilling rig that incorporates a number of features that enhance functionality and productivity, is described. The rig features modular construction, a large heated common drilling machinery room, permanently-mounted draw works which, along with the permanently installed top drive, significantly reduces rig-up/rig-down time. Also featured are closed and open hydraulic systems and a unique hydraulic distribution manifold. All functions are controlled through a programmable logic controller (PLC), providing almost unlimited interlocks and calculations to increase rig safety and efficiency. Simplified diagnostic routines, remote monitoring and troubleshooting are also part of the system. To date, two rigs are in operation. Performance of both rigs has been rated as `very good`. Little or no operational problems have been experienced; downtime has averaged 0.61 per cent since August 1998 when the the first of the two rigs went into operation. The most important future application for this rig is for use with the casing drilling process which eliminates the need for drill pipe and tripping. It also reduces the drilling time lost due to unscheduled events such as reaming, fishing and taking kicks while tripping. 1 tab., 6 figs.

Laurent, M.; Angman, P.; Oveson, D. [Tesco Corp., Calgary, AB, (Canada)

1999-11-01

89

Control rod drive system hydraulic transient analytical and transient test results for James A. FitzPatrick BWR plant  

International Nuclear Information System (INIS)

On October 14, 1981, Reactor Control, Inc., the supplier of the Control Rod Drive (CRD) System, informed the NRC that the rapid opening of insert scram valves could potentially result in a significant waterhammer transient affecting the CRD insert lines and supports in several BWR plants. As a result, all BWR plants are addressing this issue by performing analyses and tests to determine the effect of waterhammer loads on the CRD system during a scram event. The FitzPatrick plant has been operating for approximately 10 years and has experienced a sizeable number of scram events with no apparent effect on the CRD system piping and supports. This is indicative that the CRD system is capable of withstanding the waterhammer loads. The objective of this project was to upgrade the system, if needed, but to avoid expenditure of resources and manrem exposure on modifications that would not yield a gain in safety. This objective was accomplished by a combination of computer analyses and in-plant tests to realistically predict the system structure behavior under waterhammer loads. This approach would indicate that the system is adequately designed or would identify the modification needed. (orig.)

1987-01-01

90

FOREWORD: 26th IAHR Symposium on Hydraulic Machinery and Systems  

Science.gov (United States)

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

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

2012-11-01

91

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

92

Hydraulic control rod drive for a nuclear reactor  

International Nuclear Information System (INIS)

The invention pertains to the desing of a controllable lock for the axial movement of the piston rod of a hydraulic control rod drive. The lock is ineffective during seram and unintentional control rod withdrawal. (UWI)

1977-01-01

93

Sliding Control with Chattering Elimination for Hydraulic Drives  

DEFF Research Database (Denmark)

This paper presents the development of a sliding mode control scheme with chattering elimination, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives. The proposed control scheme requires only common data sheet information, no knowledge on load characteristics, and employs piston- and valve spool positions- and load- and supply pressure feedback. The main target is to overcome problems with linear controllers deteriorating performance due to the inherent nonlinear nature of such systems. In order to accomplish this task, an integral sliding mode controller is developed for the control derivative based on a reduced order model. Simulation results demonstrate strong robustness when subjected to parameter perturbations and that chattering is eliminated.

Schmidt, Lasse; Andersen, Torben Ole

2012-01-01

94

Instrumentation system for massive hydraulic fracture mapping  

Energy Technology Data Exchange (ETDEWEB)

The measurement of induced surface potentials has been used in a research effort to map the orientation of fractures created by massive hydraulic fracturing. A first generation measurement system has been developed via field testing that has successfully mapped fracture orientation. The design, layout, and operation of the instrumentation system used to generate, measure, and analyze surface potentials during a massive hydrofracture are described. The objective of this report is to aid the transfer of this technology to the private sector.

Keck, L.J.; Seavey, R.W.

1977-04-01

95

Common cause failure analysis of hydraulic scram and control rod systems in the Swedish and Finnish BWR plants  

International Nuclear Information System (INIS)

The main task of the project included the analysis of the operating experiences at the BWRs of ABB Atom design, comprising 9 units in Sweden and 2 in Finland. International experience and reference information were also surveyed. A reference application was done for the Barsebaeck plant. This pilot study covered all systems which contribute to the reactor shutdown, including also the actuation relays at the interface to the reactor protection system. The Common Load Model was used as the quantification method, which proved to be a practicable approach. This method provides a consistent handling of failure combinatorics and workable extension to evaluate localized dependence between adjacent control rod and drive assemblies (CRDAs). As part of this project, instructions of handbook style were prepared for the CCF analysis of high redundancy systems. The primary focus in the analysis of operating experience was placed on the scram valves and CRDAs. Due to the limited component population, the experiences for the scram valve constitute only a few single failures and some potential but none actual CCF event. These insights are compatible with the generic data for these valves. The experiences for the CRDAs include several single failures, and some actual and many potential CCF events of varying degree of functional impact. Special emphasis was placed to identify any multiple failure or degradation indicating that adjacent rods would be more vulnerable to failure, because such phenomena are far more critical for the scram function as compared to failure of randomly placed rods. 17 refs

1996-01-01

96

Common cause failure analysis of hydraulic scram and control rod systems in the Swedish and Finnish BWR plants  

Energy Technology Data Exchange (ETDEWEB)

The main task of the project included the analysis of the operating experiences at the BWRs of ABB Atom design, comprising 9 units in Sweden and 2 in Finland. International experience and reference information were also surveyed. A reference application was done for the Barsebaeck plant. This pilot study covered all systems which contribute to the reactor shutdown, including also the actuation relays at the interface to the reactor protection system. The Common Load Model was used as the quantification method, which proved to be a practicable approach. This method provides a consistent handling of failure combinatorics and workable extension to evaluate localized dependence between adjacent control rod and drive assemblies (CRDAs). As part of this project, instructions of handbook style were prepared for the CCF analysis of high redundancy systems. The primary focus in the analysis of operating experience was placed on the scram valves and CRDAs. Due to the limited component population, the experiences for the scram valve constitute only a few single failures and some potential but none actual CCF event. These insights are compatible with the generic data for these valves. The experiences for the CRDAs include several single failures, and some actual and many potential CCF events of varying degree of functional impact. Special emphasis was placed to identify any multiple failure or degradation indicating that adjacent rods would be more vulnerable to failure, because such phenomena are far more critical for the scram function as compared to failure of randomly placed rods. 17 refs.

Mankamo, T. [Avaplan Oy, Espoo (Finland)

1996-12-01

97

Dynamic analysis of upper hydraulic drive control rod under vibration conditions  

International Nuclear Information System (INIS)

The paper studies the dynamic response of the hydraulically driven control rod (HDCR) under vibration conditions. The governing equation of the hydraulic driving system in a non-inertial coordinate system was deduced using a characteristic method. By comparing the analysis with the experiment, the analysis program was validated. It is shown that the response of a hydraulic driving system under a dissimilar vibration load is different. Under the condition of the pulse loading with a higher acceleration and short period, the response amplitude of the control rod mainly depends on the input displacement and increases with its increase. The response amplitude is also related to the loading direction. The pulse loading in a downward direction causes the higher response of HDCR. Under the condition of an ocean wave with a lower acceleration and long period ocean wave, the response amplitude is small, and the hydraulic drive system can keep the control rod stable by self regulating. (author)

2007-09-01

98

Hydraulic Characteristics of the Maria Reactor Control Rod Seat  

International Nuclear Information System (INIS)

In the work a method and the results of hydraulic measurements accomplished on a mock up of the MARIA reactor control rod are presented. Based on the results received the mathematical equations describing the relations between water velocity in both seat gaps and the pressure drop on beryllium - graphite matrix as well as water temperature were determined. The results enable to perform a more precise thermal - hydraulic analysis of working conditions for the MARIA reactor control rods. (author)

2003-01-01

99

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

100

Efficiency-optimised CVT hydraulic and clamping system  

Energy Technology Data Exchange (ETDEWEB)

An important target of modern transmission technology is the reduction of fuel consumption. The AUDI multitronic trademark currently in production with the LuK CVT components: pulley sets, chain, hydraulic control unit with pump and damper sets a very good standard with regard to efficiency, fuel consumption and dynamic behaviour. Compared to conventional 5 speed automatic transmissions there is a fuel consumption advantage of 9%, and the time for acceleration from 0 to 60 mph is improved by 1.3 s. These values are mainly influenced by the CVT components delivered by LuK as a system supplier. Further developments of the hydraulic control, in combination with new ideas for a slip controlled clamping, show a potential to reduce fuel consumption. The benefit of the described concept including the LuK chain amounts to 7.. 10% compared to conventional CVT technologies. (orig.)

Faust, H. [VDI (Germany); Homm, M.; Reuschel, M. [VDI, Buehl (Germany)

2002-07-01

 
 
 
 
101

Thermal hydraulic analyses for introducing the derivative component of the Engineered Safety Feature Actuation System signal 'Main steam header rupture' within the Instrumentation and Control retrofitting process  

International Nuclear Information System (INIS)

The report contains 3 thermal hydraulic analyses of Main Steam Header (MSH) rupture at NPP Dukovany with VVER-440/213 with various assumptions about the failure of Reactor Trip System (RTS) and Engineered Safety Feature Actuation System (ESFAS) signals. The work was oriented on evaluation of possibility to add MSH pressure derivative based ESFAS signal for 'non-zero' power modes. The objective was to ensure diversity of ESFAS signals for MSH rupture type of accidents. The calculations were elaborated in best-estimate way (except for assumptions of RTS and ESFAS failure) with help of system thermal hydraulic code RELAP5 and with 6-loop input model of NPP Dukovany. In the model, there were reflected planned modification of I and C at NPP Dukovany. The results show that it is possible to use pressure derivatives for initiation of ESFAS signal 'MSH rupture'. (author)

2001-01-01

102

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

103

Study of the stable control system of a half-toroidal CVT during mode change - a comparison of hydraulic and mechanical loading devices  

Energy Technology Data Exchange (ETDEWEB)

In this paper, we compare some CVT systems and show that NSK's new coaxial power-split CVT has potential for higher efficiency, a wider ratio range, and is more compact. We have analyzed the influence of elastic deformation, clearance, and inertia during load transmission. Furthermore, we have compared hydraulic and mechanical loading devices, and have analyzed how they influence behavior during static and dynamic load transmission. These have been confirmed both theoretically and experimentally. (orig.)

Miyata, S.; Liu, D.; Inoue, E.; Machida, H.

2002-07-01

104

CHES-Casing Hydraulic Expert System  

Energy Technology Data Exchange (ETDEWEB)

One critical application of expert systems in the drilling industry is the design of casting strings. Tubulars are such a significant expenditure that they demand precise engineering. The availability of powerful PC's has relieved engineers of the drudgery of repetitive and intensive engineering calculations. An important way to decrease drilling costs is to increase the bit penetration rate. The less time spent drilling a hole, the fewer problems that are incurred. Most hole problems develop slowly and become serious considerations only after enough times has passed. Optimizing bit hydraulics to increase drilling rate is an important task facing drilling engineers. Rheology, hydraulics, and bit-nozzle selection are parameters to be considered when optimizing drilling. CHES is written with an expert-system shell (LEVEL-5, from Information Builders Inc.). The backward-chaining rule base interfaces with DB3 (Database 3), numerous FORTRAN programs, and chains from one knowledge base to another. CHES was developed and implemented on an IBM PC AT microcomputer.

Heinze, L.R. (Texas Tech Univ., Lubbock, TX (United States))

1993-02-01

105

Hydraulic conductivity of compacted soils controlled by microbial activity.  

Science.gov (United States)

The hydraulic conductivity defines the displacement of liquids inside porous media and affects the fate and transport of contaminants in the environment. In this research the influence of microbial growth and decay inside soil pores on hydraulic conductivity is analysed. Long-term tests performed in silt-bentonite mixtures permeated with distilled water and a nutrients solution demonstrated that hydraulic conductivity of compacted silt-bentonite samples decreases with time of permeation as a bioclogging mechanism develops. The injection of antibiotics and antifungals in the specimens produces a rebound in the hydraulic conductivity associated with the decay of microbial activity. These results show that biomediated reactions can be used to control the flow rate through compacted soil liners. PMID:24956782

Glatstein, Daniel Alejandro; Francisca, Franco Matías

2014-08-01

106

Hydraulic system for a support section with Movamle baffle  

Energy Technology Data Exchange (ETDEWEB)

A hydraulic system for a support section with retractable baffle including a hydraulic prop, a hydraulic travel jack, a hydraulic jack for the retractable baffle, a multi-position hydraulic distributor, and water main check valve is proposed. To prevent exposing the roof when the support section moves and to eliminate self-propelled movement by the baffle, the section is equipped with a hydraulically balanced two-position switch, which is connected with the piston cavity of the baffle jack, and with the hydrodistributor, and with the logic unit by means of which the hydraulic distributor is connected to the rod cavity of the baffle jack. This approach decreases the amount of roof rock entering the working area when the support section is moving and prevents accidents.

Polyey, L.S.; Mikhailov, I.F.; Nuginov, P.N.

1980-08-07

107

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

108

HYDRAULICS OF THE ATCHAFALAYA BASIN MAIN CHANNEL SYSTEM: CONSIDERATIONS FROM A MULTIUSE MANAGEMENT STANDPOINT  

Science.gov (United States)

The report examines the relationships among hydraulic elements in the Atchafalaya Basin floodway system in terms of discharge regime, sediment load, channel form and size, flood control, water surface slope, bank elevation, overbank capacity, dredging requirements, and spoil disp...

109

Powertrain System HANT: Hydraulic Pump/Motor  

Energy Technology Data Exchange (ETDEWEB)

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

1993-06-01

110

Proceedings of the Twenty-First Water Reactor Safety Information Meeting: Volume 1, Plenary session; Advanced reactor research; advanced control system technology; advanced instrumentation and control hardware; human factors research; probabilistic risk assessment topics; thermal hydraulics; thermal hydraulic research for advanced passive LWRs  

International Nuclear Information System (INIS)

This three-volume report contains 90 papers out of the 102 that were presented at the Twenty-First Water Reactor Safety Information Meeting held at the Bethesda Marriott Hotel, Bethesda, Maryland, during the week of October 25--27, 1993. The papers are printed in the order of their presentation in each session and describe progress and results of programs in nuclear safety research conducted in this country and abroad. Foreign participation in the meeting included papers presented by researchers from France, Germany, Japan, Russia, Switzerland, Taiwan, and United Kingdom. The titles of the papers and the names of the authors have been updated and may differ from those that appeared in the final program of the meeting. Individual papers have been cataloged separately. This document, Volume 1 covers the following topics: Advanced Reactor Research; Advanced Instrumentation and Control Hardware; Advanced Control System Technology; Human Factors Research; Probabilistic Risk Assessment Topics; Thermal Hydraulics; and Thermal Hydraulic Research for Advanced Passive Light Water Reactors

1993-10-25

111

Analysis of and Hâ?? 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 Hâ??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, Søren; Pedersen, Henrik C.

2011-01-01

112

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mobile hydraulics is in a transition phase, where electronic sensors and digital signal processors are starting to become standard on a high number of machines, hereby replacing hydraulic pilot lines and oering new possibilities with regard to both control and feasibility. For controlling some of the existing hydraulic components there are, however, still a need for being able to generate a hydraulic pilot pressure, as e.g. almost all open-circuit pumps are hydraulically controlled. The focus...

Pedersen, Henrik C.; Andersen, Torben Ole; Madsen, A. M.; Dahl, M.; Nielsen, B. K.; Stubkier, Søren

2009-01-01

113

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mobile hydraulics is in a transition phase, where electronic sensors and digital signal processors are starting to become standard on a high number of machines, hereby replacing hydraulic pilot lines and oering new possibilities with regard to both control and feasibility. For controlling some of the existing hydraulic components there are, however, still a need for being able to generate a hydraulic pilot pressure, as e.g. almost all open-circuit pumps are hydraulically controlled. The focus...

Pedersen, Henrik C.; Andersen, Torben Ole; Madsen, A. M.; Dahl, M.; Nielsen, B. K.; Stubkier, Søren

2010-01-01

114

Hydraulic power take-off for wave energy systems  

DEFF Research Database (Denmark)

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

Christensen, Georg Kronborg

2001-01-01

115

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

116

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 (HAWTâ??s). HAWTâ??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 WTâ??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, Søren; Pedersen, Henrik C.

2011-01-01

117

Hydraulically actuated hexapod robots design, implementation and control  

CERN Multimedia

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

118

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

2008-08-01

119

Quantitative fault tolerant control design for a hydraulic actuator with a leaking piston seal  

Science.gov (United States)

Hydraulic actuators are complex fluid power devices whose performance can be degraded in the presence of system faults. In this thesis a linear, fixed-gain, fault tolerant controller is designed that can maintain the positioning performance of an electrohydraulic actuator operating under load with a leaking piston seal and in the presence of parametric uncertainties. Developing a control system tolerant to this class of internal leakage fault is important since a leaking piston seal can be difficult to detect, unless the actuator is disassembled. The designed fault tolerant control law is of low-order, uses only the actuator position as feedback, and can: (i) accommodate nonlinearities in the hydraulic functions, (ii) maintain robustness against typical uncertainties in the hydraulic system parameters, and (iii) keep the positioning performance of the actuator within prescribed tolerances despite an internal leakage fault that can bypass up to 40% of the rated servovalve flow across the actuator piston. Experimental tests verify the functionality of the fault tolerant control under normal and faulty operating conditions. The fault tolerant controller is synthesized based on linear time-invariant equivalent (LTIE) models of the hydraulic actuator using the quantitative feedback theory (QFT) design technique. A numerical approach for identifying LTIE frequency response functions of hydraulic actuators from acceptable input-output responses is developed so that linearizing the hydraulic functions can be avoided. The proposed approach can properly identify the features of the hydraulic actuator frequency response that are important for control system design and requires no prior knowledge about the asymptotic behavior or structure of the LTIE transfer functions. A distributed hardware-in-the-loop (HIL) simulation architecture is constructed that enables the performance of the proposed fault tolerant control law to be further substantiated, under realistic operating conditions. Using the HIL framework, the fault tolerant hydraulic actuator is operated as a flight control actuator against the real-time numerical simulation of a high-performance jet aircraft. A robust electrohydraulic loading system is also designed using QFT so that the in-flight aerodynamic load can be experimentally replicated. The results of the HIL experiments show that using the fault tolerant controller to compensate the internal leakage fault at the actuator level can benefit the flight performance of the airplane.

Karpenko, Mark

120

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. Todayâ??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

 
 
 
 
121

Device for remote control of multiple-position hydraulic distributors  

Energy Technology Data Exchange (ETDEWEB)

The device for remote control of multiple-position hydraulic distributors, predominantly for mechanized timberings contains a flexible linkage with clamps interacting with the distributors, drive and control panel. To simplify the design and guarantee selective multiple-position switching, the flexible linkage is made in the form of a closed element and is equipped with autonomous drive, while the clamps are arranged on the flexible linkage with spacing corresponding to the positions of the distributors.

Bogdanov, Yu.V.; Chernov, V.D.; Nikiforov, A.F.; Shcherbakov, L.F.; Vogdanova, L.Z.

1980-07-30

122

Control of dynamic effects in small hydro with long hydraulic circuits  

Energy Technology Data Exchange (ETDEWEB)

Lab tests in a long hydraulic circuit were developed to analyse hydrotransients induced by waterhammer effects under runaway conditions. The definition of suitable design criteria in hydraulic systems is of utmost importance and has become a priority for good design implementation. The dynamic behaviour of turbo-generators of small reaction turbines and the interaction with long hydraulic circuits are the major constraints for design criteria. In small reaction turbines, runaway conditions may cause significant discharge variations and consequently pressure fluctuations. A benchmark analysis based on the hydrodynamic behaviour of the system through computer simulations and experimental tests was developed. Specific unconventional protection devices were selected to control overpressures induced by runaway conditions in small hydropower systems with lesser environmental impacts. A spectral analysis was used in order to identify the influence of each type of disturbances in the system response. (Author)

Ramos, H.; Betamio De Almeida, A. [Technical Univ., Lisbon (Portugal). Dept. of Civil Engineering

2005-07-01

123

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

1989-01-01

124

Development of A Hydraulic Drive for a novel Diesel-Hydraulic system for Large commercial Vehicles  

DEFF Research Database (Denmark)

The objectives and results of the research project Hybrid Diesel-Hydraulic System for Large commercial vehicles, e.g. urban freight delivery, buses or garbage trucks. The paper presents and discusses the research and development of the system, modelling approach and results from preliminary performance tests on a 10 ton vehicle.

Conrad, Finn

2002-01-01

125

Hydraulic system with active residual backwater for mechanized extracting complexes  

Energy Technology Data Exchange (ETDEWEB)

An examination is made of the realized design improvements in the hydraulic system of mechanized stoping complexes OMKT-M and OKP designed for specific conditions of the lines in the Zapadnomaritskiy Basin. The valve block of the active residual backwater was designed jointly by the Bulgarian institute MNTPKI ''Minproyekt'' and the institute of mining imeni A. A. Skochinskiy. It was the basis for designing a new mechanized complex with hydraulic system equipped with flexible main pipelines. Basic technical parameters of the new hydraulic system are presented.

Khadzhidimov, G.; V' rbanova, P.

1981-01-01

126

High-pressure hydraulic system for a continuously variable transmission; Belt shiki mudan hensokuki no koyuatsu system  

Energy Technology Data Exchange (ETDEWEB)

In a belt-type continuously variable transmission (CVT), the belt-clamping force is produced by a hydraulic piston and the speed is changed by the stroke of the piston. Such being the case, the hydraulic system demands a higher pressure and greater flow than the conventional automatic transmission and, for the improvement of fuel consumption and drivability, it should be so arranged that an appropriate gear ratio is available even during transition. For the improvement of vehicle fuel consumption, it is important to develop a variable gear ratio servo system for the hydraulic system of the belt-type CVT, this for the reduction of energy consumption and for the embodiment of desired gear ratio characteristics. In this report, the hydraulic system for the CVT and part of the applied technology are outlined. In the case of a large-capacity belt-type CVT, thanks to the employment of the hydraulic system discussed here, the required flow is decreased and optimum hydraulic control is performed under all driving conditions, and these keep low the power that the hydraulic system consumes. This contributes to the improvement of vehicle fuel consumption. The high-pressure hydraulic system which the conventional automatic transmission lacks is kept from being large in dimension, and reliability is at the same time assured. (NEDO)

Oshidari, T. [Nissan Motor Co. Ltd., Tokyo (Japan)

1999-03-15

127

A High-Pressure Injection Hydraulic Transport System with a Peristaltic Pump Conveyor.  

Science.gov (United States)

The patent application relates generally to hydraulic transport of solids, and more particularly, to a system for hydraulic transport of mined coal from the mine face using a peristaltic pump conveyor. A high-pressure injection hydraulic transport system ...

Kleysteuber Bean

1976-01-01

128

Technology of load-sensitivity used in the hydraulic system of an all-hydraulic core rig  

Energy Technology Data Exchange (ETDEWEB)

Existing hydraulic systems always have problems of temperature rise, running stability and anti-interference of the implementation components, reliability of hydraulic components, maintenance difficulties, and other issues. With high efficiency, energy saving, reliability, easy operating, stable running, anti-interference ability, and other advantages, a load-sensitive hydraulic system is more suitable for coal mine all-hydraulic core rig. Therefore, for the technical development of the coal mine all-hydraulic core rig, the load-sensitive technology employed by the rig should be of great significance. 10 refs., 6 figs.

De-zhong Xin; Song-ling Chen; Qing-feng Wang [China Coal Research Institute, Chongqing (China). Chongqing Research Institute

2009-09-15

129

Geosiphon(TM) Ground Water Remediation System Hydraulics  

International Nuclear Information System (INIS)

Two, pilot-scale, GeoSiphon(TM) systems have been installed and tested for the treatment of contaminated ground water at the Savannah River Site (SRS). These systems consisted of an in situ treatment cell located in an area of higher hydraulic head and a siphon connecting the cell to a surface stream at a lower hydraulic head. The siphon induced contaminated ground water flow through a permeable treatment media in the cells and transported the treated water to the discharge points in a surface stream. The hydraulic head available to drive the systems is divided between the head losses associated with the treatment cell and siphon. Six different treatment cell configurations and seven different siphon configurations have been hydraulically evaluated in association with both pilot-scale systems. The results provide valuable guidelines for the design of GeoSiphon systems

2002-04-30

130

Geosiphon(TM) Ground Water Remediation System Hydraulics  

Energy Technology Data Exchange (ETDEWEB)

Two, pilot-scale, GeoSiphon(TM) systems have been installed and tested for the treatment of contaminated ground water at the Savannah River Site (SRS). These systems consisted of an in situ treatment cell located in an area of higher hydraulic head and a siphon connecting the cell to a surface stream at a lower hydraulic head. The siphon induced contaminated ground water flow through a permeable treatment media in the cells and transported the treated water to the discharge points in a surface stream. The hydraulic head available to drive the systems is divided between the head losses associated with the treatment cell and siphon. Six different treatment cell configurations and seven different siphon configurations have been hydraulically evaluated in association with both pilot-scale systems. The results provide valuable guidelines for the design of GeoSiphon systems.

Phifer, M.A.

2002-04-30

131

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

132

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 accomodating tank, have been analyzed and a preliminary analysis system has been set up for development of the analysis and design methodology for the system. The work was the results of the second year research in the planned research period of four years. Analysis has been made for the characteristics of rapid transient and steady flow in the piping, steam condensation, small and hermetically sealed tank performance, bubble behavior and wall pressure oscillation in a large and open tank, coupling between wall pressure oscillation and structure vibration. Based on the analysis results, conceptual methods for controlling the hydraulic load on the wall have been devised and evaluated. (Author)

1993-01-01

133

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

134

The Iterative Learning Control for the Position Tracking of the Hydraulic Cylinder  

Science.gov (United States)

The iterative learning control (ILC) learns the unknown information from repeated control operations. The tracking error from previous stages is used as the correction factor for the next control action. Therefore, the ILC controller can make the system tracking error converge to a small region within the limited numbers of iterations. In this paper, a proportional-valve-controlled hydraulic cylinder system with repeated external loads is built to perform the position tracking control experiments. The PID and ILC controllers are implemented in these experiments and the results are compared. The P-type update law with delay parameter is used for its position tracking control. Experimental results show that the ILC controller can effectively controls the system to track the repetitive position trajectory, especially in transient response that traditional control methods can't follow appropriately. Therefore, in this application, the control performance of the ILC is superior to the traditional PID controller.

Chen, Chih-Keng; Zeng, Wei-Cheng

135

Hydraulically driven control rod concept for integral reactors: fluid dynamic simulation and preliminary test  

International Nuclear Information System (INIS)

The paper deals with the preliminary study of the Hydraulically Driven Control Rod concept, tailored for PWR control rods (spider type) with hydraulic drive mechanism completely immersed in the primary water. A specific solution suitable for advanced versions of the IRIS integral reactor is under investigation. The configuration of the Hydraulic Control Rod device, made up by an external movable piston and an internal fixed cylinder, is described. After a brief description of the whole control system, particular attention is devoted to the Control Rod characterization via Computational Fluid Dynamics (CFD) analysis. The investigation of the system behavior, including dynamic equilibrium and stability properties, has been carried out. Finally, preliminary tests were performed in a low pressure, low temperature, reduced length experimental facility. The results are compared with the dynamic control model and CFD simulation model, showing good agreement between simulations and experimental data. During these preliminary tests, the control system performs correctly, allowing stable dynamic equilibrium positions for the Control Rod and stable behavior during withdrawal and insertion steps. (author)

2003-09-15

136

Energy efficient hydraulic systems for large engines  

Energy Technology Data Exchange (ETDEWEB)

Hydrostatic power offers considerable advantages in terms of transmission flexibility, controllability and power density. There are many potential uses for hydrostatic power on large engines, of which several are standard on low speed two-strokes. Bosch Rexroth and a partner company have developed hydrostatic systems for converting surplus energy in engine exhaust gases into interesting fuel saving options, including power-take-in at the crankshaft and driving auxiliary systems. (orig.)

Fischer, Steffen [Bosch Rexroth AG, Lohr am Main (Germany)

2013-10-15

137

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)

2009-04-01

138

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

2006-04-01

139

Design of a Hydraulic Motor System Driven by Compressed Air  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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....

Dein Shaw; Jyun-Jhe Yu; Cheng Chieh

2013-01-01

140

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

 
 
 
 
141

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

2000-11-22

142

Method and apparatus for controlling hydraulically-operated continuously variable transmission of belt-and-pulley type  

Energy Technology Data Exchange (ETDEWEB)

A hydraulic control system is described for controlling a speed ration of a hydraulically-operated continuously variable transmission of a vehicle, having (1) an input shaft operatively connected to an engine of the vehicle (2) an output shaft operatively connected to an engine of the vehicle, (3) a pair of variable-diameter pulleys mounted on the input and output shafts, respectively, (4) a transmission belt connecting the pair of variable diameter pulleys, and (5) a pair of hydraulic cylinders for changing an effective diameter of the pair of pulleys, respectively. The hydraulic control system includes a speed-ratio control valve assembly associated with one of the hydraulic cylinders. The control valve assembly is selectively placed in one of three states of operation consisting of a first state in which a pressurized fluid is fed to the one of the hydraulic cylinders, a second state in which the fluid is discharged from the one hydraulic cylinder, and a third state in which the feed or discharge flow of the fluid to or from the one hydraulic cylinder is restricted. The improvement described here comprises: detecting means for detecting an actual value of a variable to be controlled, such as a speed of the engine or a speed ratio of the transmission; first determining means for determining a target value of the variable, based at least on a currently required output of the engine and according to a predetermined relation between the target value and the required output; second determining means for determining a difference between the target value and the actual value of the variable to be controlled; and control means for controlling the operation of the speed-ratio control valve assembly so that the difference is reduced.

Itoh, H.; Hiramatsu, S.; Takada, M.; Tamura, T.

1986-12-16

143

Development of realistic thermal-hydraulic system analysis codes ; development of thermal hydraulic test requirements for multidimensional flow modeling  

Energy Technology Data Exchange (ETDEWEB)

This study is concerned with developing a multidimensional flow model required for the system analysis code MARS to more mechanistically simulate a variety of thermal hydraulic phenomena in the nuclear stem supply system. The capability of the MARS code as a thermal hydraulic analysis tool for optimized system design can be expanded by improving the current calculational methods and adding new models. In this study the relevant literature was surveyed on the multidimensional flow models that may potentially be applied to the multidimensional analysis code. Research items were critically reviewed and suggested to better predict the multidimensional thermal hydraulic behavior and to identify test requirements. A small-scale preliminary test was performed in the downcomer formed by two vertical plates to analyze multidimensional flow pattern in a simple geometry. The experimental result may be applied to the code for analysis of the fluid impingement to the reactor downcomer wall. Also, data were collected to find out the controlling parameters for the one-dimensional and multidimensional flow behavior. 22 refs., 40 figs., 7 tabs. (Author)

Suh, Kune Yull; Yoon, Sang Hyuk; Noh, Sang Woo; Lee, Il Suk [Seoul National University, Seoul (Korea)

2002-03-01

144

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)

2009-05-01

145

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.

2012-11-26

146

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

147

ATHENA: a thermal hydraulic simulation code for space reactor system design and analysis  

International Nuclear Information System (INIS)

This paper describes the general capabilities available in the Advanced Thermal-Hydraulic Energy Network Analyzer (ATHENA) code and emphasizes those features particularly applicable to space reactor system analysis. This code has been developed as a part of the Department of Energy (DOE) Fusion Safety program for use in safety analysis of magnetic fusion systems. ATHENA is designed for transient thermal hydraulic analysis of systems which contain one or several fluid circuits with thermal interactions. The fluid systems can be either one or two phase and can contain a variety of component types such as pumps, valves, heat pipes, separators, and control systems. The ATHENA code has wide applicability for transient thermal hydraulic analysis and is currently being used for transient system simulation of candidate space reactor concepts

1986-01-13

148

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

149

System of controlling a blowout preventer  

Energy Technology Data Exchange (ETDEWEB)

A system is proposed for controlling a blowout preventer which includes hydraulically controllable hydraulic distributors of opening and closing the blowout preventer with spring return connected respectively to the cavities of opening and closing the hydraulic cylinders of the blowout preventer drive, pressure line connected to the hydraulic distributors for opening and closing the blowout preventer, overflow line connected to the hydraulic distributor for opening the blowout preventer, and line for controlling the hydraulic distributors for opening and closing the blowout preventer connected respectively to the chambers for controlling them. In order to improve its reliable operation by guaranteeing fixing of the blowout preventer in closed position with unloaded line for controlling the hydraulic distributor of closing the blowout preventer, it is equipped with additional hydraulically controlled hydrodistributor with spring return installed between the cavities for closing the hydraulic cylinders of the blowout preventer drive and the overflow line, and the hydraulic distributor for closing the blowout preventer and additional hydraulic distributor are normally closed.

Alabushev, V.Ye.; Khokhlov, Yu.I.; Stakhov, B.G.

1982-01-01

150

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

151

Profile section equipped with sealing systems for making a pressurised hydraulic circuit utilizable for the cultivation of photosynthetic organisms under controlled conditions  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A solution is described that enables a pressurised hydraulic circuit to be made inside the channels of an alveolar panel; the panel can be made of a transparent plastic material that enables the liquid to be irradiated by external light; the panel in a transparent material can be used as a light exposure apparatus of a photobioreactor destined to the cultivation of various types of organisms; the organisms produced can be used in the fields of energy generation, pharmaceutics, nutrition.

2012-01-01

152

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

International Nuclear Information System (INIS)

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

1991-01-01

153

A Device for Sampling the Working Fluid from Hydraulic Systems.  

Science.gov (United States)

An Author Certificate has been issued for a device for removing hydraulic-fluid samples as described by Author Certificate No. 183474. To eliminate the falling of extraneous particles into the receiving tank, an additional cut-off control valve is provide...

Y. P. Gribkov L. P. Shnykin V. G. Sborshchikov A. V. Mikheev A. I. Zharikov

1969-01-01

154

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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, see...

2010-01-01

155

Study on the Energy-Regeneration-based Velocity Control of the Hydraulic-Hybrid Vehicle  

Directory of Open Access Journals (Sweden)

Full Text Available This paper simplifies the energy regenerationbased vehicle velocity system of the hydraulichybrid businto a process in which the extension rod of the hydraulic cylinder drives the secondary-element variable delivery pump/motor to change its displacement. This process enables braking of the vehicle and also allows recovery of energy. The stability, energy efficiency and other characteristics of the system are studied based on analysis of mathematical models of the vehicle velocity control. The relevant controller is designed to study effects of the controller on system characteristics. The vehicle velocity control module of the energy regeneration system is stable and able to recovery the inertia energy generated in vehicle braking. After the controller intended to improve response speed is added, system response becomes quicker but energy recovery rate declines.

SONG Yunpu

2012-11-01

156

Design of a drive system for a side-dumping loader with optimization of hydraulic system parameters  

Energy Technology Data Exchange (ETDEWEB)

Discusses design of control systems for a side-dumping loader for underground coal mines. The loader is equipped with a bucket with a capacity of 1.2 m{sup 3} and electric motors with a power of 55 kW. The drive system consists of 2 independent units: a travelling unit with 2 hydraulic engines (SH1 and SH2 with a tramsmission gear) and a drive unit for the bucket with rams (S1, S2, S3 for bucket lifting and side-dumping). A load sensing control system is used for control of a hydraulic pump (with the DFR controller) that distributes working fluid in the travelling system and the bucket lifting system. Replacing other conventional control systems with the load sensing system economizes 11-14% of energy previously consumed. 3 refs.

Bliznicki, E.; Koldras, A. (Centrum Mechanizacji Gornictwa KOMAG, Gliwice (Poland))

1988-10-01

157

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

Energy Technology Data Exchange (ETDEWEB)

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.

You, Seung Han [Hyundai Motor Company, Seoul (Korea, Republic of); Hahn, Jin Oh [University of Alberta, Edmonton (Canada)

2012-05-15

158

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

2012-05-01

159

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

CERN Multimedia

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

160

Hydraulic drive with a control rod for nuclear reactors  

International Nuclear Information System (INIS)

For a control rod with a piston part, which consists of alternate projections and grooves on a piston rod, and with a cylinder, which also has alternate projections and grooves, and which surrounds the piston rod, the cylinder has at least two groups of projections and grooves. There is a space between the two groups, in which the diameter of the cylinder is greater than the diameter of the projections. Therefore, the piston rod is provided with projections and grooves over at least the length of the space, is surrounded by one or other group and is kept stationary or moved by hydraulic liquid. The piston rod is made as a tube surrounding an absorber material (B_4C, Hf, steel), particularly for a heavy water-cooled BWR. (orig./HP)

1984-07-25

 
 
 
 
161

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

2010-12-01

162

Hydraulic simulation of the Vodice water supply system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Many Slovenian communities are facing drinking water supply issues. Major problems are the life span of pipelines and other supply system equipment, undersized water supply network and inappropriate pipeline material. The community of Vodice is facing the previously- described issues. A need to reconstruct and recondition the drinking water pipeline system was identified. It was necessary to develop a hydraulic model of Vodice’s drinking water pipeline system. A simulation, based on the hyd...

C?epon, Jerneja

2008-01-01

163

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

164

Non Linear Modelling and Control of Hydraulic Actuators  

Directory of Open Access Journals (Sweden)

Full Text Available This paper deals with non-linear modelling and control of a differential hydraulic actuator. The nonlinear state space equations are derived from basic physical laws. They are more powerful than the transfer function in the case of linear models, and they allow the application of an object oriented approach in simulation programs. The effects of all friction forces (static, Coulomb and viscous have been modelled, and many phenomena that are usually neglected are taken into account, e.g., the static term of friction, the leakage between the two chambers and external space. Proportional Differential (PD and Fuzzy Logic Controllers (FLC have been applied in order to make a comparison by means of simulation. Simulation is performed using Matlab/Simulink, and some of the results are compared graphically. FLC is tuned in a such way that it produces a constant control signal close to its maximum (or minimum, where possible. In the case of PD control the occurrence of peaks cannot be avoided. These peaks produce a very high velocity that oversteps the allowed values.

B. Šulc

2002-01-01

165

The root system as a hydraulic architecture: principles and applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Many hydrological models including the process of root water uptake (RWU) do not consider the dimension of root system hydraulic architecture (HA) because explicitly solving water flow in such a complex system is too time consuming. However, they might lack process understanding when basing RWU and plant water stress predictions on functions of variables such as the root length density distribution. On the basis of analytical solutions of water flow equations in a HA, we developed and validat...

Couvreur, Valentin; Meunier, Fe?licien; Vanderborght, Jan; Javaux, Mathieu; Hydrus, Workshop

2013-01-01

166

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

167

Transputers in Fluid Power - Design and Applications. Chapter 5 in Advances in Hydraulic Control Systems. : A SERG Publication - SERG: Subsea Engineering Research Group.  

DEFF Research Database (Denmark)

Deals with results and trends on mechatronics in fluid power and intelligent control of machines and robots. New results are presented concerning transputer-basen distributed control of machines and robots. Experimental results with the DTU mechatronic test facility are presented and discussed. Several adaptive control algoritms are investigated and evaluated. Promissing results are obtained with Computed Valve-Input Control (CIC), Adaptive Model-based Actuator Control (AMAC) and Linear Pertubation Adaptive Control (LPAC).

Conrad, Finn

1996-01-01

168

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 â?? = 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.

Sørensen, Rasmus Mørk; Hansen, Michael Rygaard

2011-01-01

169

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

170

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

171

Control system for the feed of pressurized fluid in a hydraulic circuit as a function of the state of the locking or unlocking of two mechanical organs. [PWR primary pumps]. Dispositif de commande de l'alimentation en fluide sous pression d'un circuit hydraulique en fonction de l'etat de verrouillage ou de deverrouillage de deux organes mecaniques  

Energy Technology Data Exchange (ETDEWEB)

The control system comprises two hydraulic cylinders of which rods are integral with the mechanical organs. The piston of the first cylinder separates the chamber of this one in two parts. The piston of the second cylinder separates its chamber in three parts. The inlet chamber of the two cylinders are connected to pressurized fluid feed pipes, and the outlet chambers to a depressurization pipe. According to the position of the piston depending itself on the state of locking or unlocking of the rods, an interconnection pipe and a feed pipe of the pressurized fluid hydraulic circuit communicate with a chamber or another one. The feed of the hydraulic circuit is possible only the two rods are unlocked. The invention applies more particularly to the feed of the control circuit of an emergency seal of the primary pump of a pressurized water nuclear reactor.

Huet, Y.; Perichon, C.

1985-06-21

172

Modeling and Experimental Tests on the Hydraulically Driven Control Rod option for IRIS Reactor  

International Nuclear Information System (INIS)

The adoption of Internal Control Rod Drive Mechanisms (ICRDMs) represents a valuable alternative to classical, external CRDMs based on electro-magnetic devices, as adopted in current PWRs. The advantages on the safety features of the reactor are apparent: inherent elimination of the Rod Ejection accidents and of possible concerns about the vessel head penetrations. A further positive feedback on the design is the reduction of the primary system overall dimensions. Within the frame of the ICRDM concepts, the Hydraulically Driven Control Rod solution is investigated as a possible option for the IRIS integral reactor. After a brief comparison of the solutions currently proposed for integral reactors, the configuration of the Hydraulic Control Rod device for IRIS, made up by an external movable piston and an internal fixed cylinder, is described. A description of the whole control system is reported as well. Particular attention is devoted to the Control Rod profile characterization, performed by means of a Computational Fluid Dynamics (CFD) analysis. The investigation of the system behavior has been carried out, including the dynamic equilibrium and its stability properties, the withdrawal and insertion step movement and the sensitivity study on command time periods. A suitable dynamic model has been set up for the mentioned purposes: the models corresponding to the various Control Rod system devices have been written in an Object-Oriented language (Modelica), thus allowing an easy implementation of such a system into the simulator for the whole reactor. Finally, a preliminary low pressure, low temperature, reduced length experimental facility has been built. Tests on HDCR stability and operational transients have been performed. The results are compared with the dynamic system model and CFD simulation model, showing good agreement between simulations and experimental data. During these preliminary tests, the control system performed correctly, allowing stable dynamic equilibrium positions for the Control Rod and stable behavior during withdrawal and insertion steps. (authors)

2004-06-13

173

Comparison of mechanical and hydraulic transmission systems for aerogenerators. Volume 1  

Energy Technology Data Exchange (ETDEWEB)

The report presented is concerned with studies of three types of aerogenerator transmission systems namely, fixed pitch rotor hydraulic, variable pitch rotor mechanical, and fixed pitch rotor mechanical, each type being considered in three sizes. The study covers systems design, control, performance, reliability/availability, weight, wind speed effects from three sites, energy yields, and energy costs. The principal results and conclusions discussed include that for many applications, the principal advantages of the hydraulic system compared with the variable pitch mechanical system are unlikely to outweigh its principal disadvantages e.g. lower energy yield, higher energy costs, and development requirements, the fixed pitch rotor mechanical system is the least attractive of the three types of system, and for all the systems, high wind speed sites are preferred because they yield more energy at significantly lower unit energy costs.

1982-12-01

174

Optimisation of Working Areas in Discrete Hydraulic Power Take off-system for Wave Energy Converters  

DEFF Research Database (Denmark)

Fluid power is the leading technology in Power Take Off(PTO) systems in Wave Energy Converters(WECâ??s), due to the capability of generating high force at low velocity. However, as hydraulic force controlling system may suffer from large energy losses the efficiency of the hydraulic PTO systems may be a limiting factor for wave energy. Therefore, a secondary controlled force system has been proposed as PTO element for WECâ??s. This paper investigates the configuration of a multi-chamber cylinder utilising two common pressure lines. By usage of model based optimisation an optimal number and size of working areas is proposed. This area encoding strategy is investigated and compared to two standard binary encodings, finding that the optimised area coding yields significantly higher energy output.

Hansen, Anders Hedegaard; Hansen, Rico Hjerm

2012-01-01

175

Thermal-hydraulic tests for reactor safety system  

International Nuclear Information System (INIS)

Tests for the safety depressurization system, Sparger adopted for the Korean next generation reactor, APR1400 are carried out for several geometries with the B and C (Blowdown and Condensation) facility in the condition of high temperature and pressure and with a small test facility in the condition of atmospheric temperature and pressure. Tests for the critical heat flux are performed with the RCS(Reactor Coolant System) facility as well as with the Freon CHF Loop in the condition of high temperature and pressure. The atmospheric temperature and pressure facility is utilized for development of the high standard thermal hydraulic measurement technology. The optical method is developed to measure the local thermal-hydraulic behavior for the single and two-phase boiling phenomena

2002-01-01

176

The development of radiation hardened robot for nuclear facility - Development of embedded controller for hydraulic robot  

Energy Technology Data Exchange (ETDEWEB)

We designed and implemented a reliable hierarchical control system for hydraulic robots for nuclear power plant maintenance. In hazardous environments such as nuclear power plants, robot systems or automated equipment should be used instead of human being for maintenance and repair. Such robot should guarantee high reliability in hazardous environments such as high radiation or high temperature. The overall system is composed of three hierarchical subsystems: i) supervisory controller in safe zone for operator interaction with monitoring and commanding and graphic user interface, ii) master controller in semi-hazardous zone for control function, and iii) slave controller in hazardous zone for sensing and actuation. These subsystems are connected with suitable communication channels: a) master-slave communication channel implemented with CAN (Control Area Network) and b) supervisory-master communication with Ethernet. The master and the slave controllers construct a feedback closed-loop control system. In order to improve reliability, the slave controller is duplicated using cold-standby scheme, and master-slave communication channel is also duplicated. The overall system is implemented harmonically, and we obtained fast control interval of 1msec, which is sufficient for high-performance real-time control. 12 refs., 58 figs., 13 tabs. (Author)

Kim, Byung Kook; Kim, Jae Kwon [Korea Advanced Institute of Science and Technology, Taejon (Korea)

2000-04-01

177

Pneumatic and Hydraulic Systems in Coal Fluidized Bed Combustor  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 const...

Opafunso, Z. O.; Ozigis, I. I.; Adetunde, I. A.

2009-01-01

178

Hydraulic External Pre-Isolator System for LIGO  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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)...

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.

2013-01-01

179

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)

1994-01-01

180

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

 
 
 
 
181

A "low-cost" hydraulic system to assure constant (rain) intensity produced by rainfall simulators  

Science.gov (United States)

Rainfall simulators are used to produce artificial rainfall both in the laboratory and in the field, and are particularly useful in soil erosion and surface hydrology studies. Although permitting a controllable, reliable and predictable simulation of rainfall events, rainfall simulators cannot replicate the unpredictable variability of natural rainfall. However, they provide a helpful tool to study the rainfall-runoff process at small scales. The aim of any rainfall simulator is the collection of accurate and useful data. However, better simulators will allow attaining data that is more accurate, thus leading to more consistent and useful models or to a better visualization and understanding of the physical processes. This study describes a hydraulic system to be attached to the nozzle of a rainfall simulator in order to eliminate pressure fluctuations, even if water supply pressure fluctuates. The hydraulic system consists of a chamber with steady pressure which supplies the nozzle, achieved by combining a pressure reduction valve after the water intake and a headloss valve before the outflow hose, thus ensuring a constant pressure level (and so a constant rainfall intensity) throughout each rainfall event. This hydraulic system was developed at the Laboratory of Hydraulics, Water Resources and Environment of the Department of Civil Engineering of the University of Coimbra. The system's ability to control the rainfall intensity is demonstrated by carrying out a set of laboratory rainfall simulations. In these simulations, high precision pressure transducers were used to measure, at a rate of 0.01s, the pressure at the water supply intake and at the nozzle. The results show that, with this hydraulic system, rainfall simulators can operate with constant (rainfall) intensity during the entire simulations.

Isidoro, Jorge; de Lima, João

2013-04-01

182

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

2007-01-01

183

Special hydraulic tests of emergency cooling system, L-Area  

Energy Technology Data Exchange (ETDEWEB)

The delay in the L-Area startup provides an opportunity to obtain valuable data on the emergency cooling system (ECS). A series of special hydraulic tests of the ECS are proposed for L-Area. These tests are in addition to the test proposed by SRL. The tests will provide much needed empirical hydraulic data on the ECS piping for incorporation in computer models as well as improve the accuracy of manual calculations. The improved modeling and accuracy will permit reactor operation at the highest safe power level with respect to an ECS power limit. The magnetic flow meters in the ECS supply piping will allow rapid and accurate data collection. No special test equipment will be required. Only standard pressure and differential pressure instruments will be required in addition to the in-line flowmeters.

Merz, G.F.

1985-05-06

184

Control arrangement for at least two hydraulic consumers fed by at least one pump  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a control arrangement for a system having at least two hydraulic consumers, at least one pump, respective direction and speed controlling valve means associated between the pump and each consumer, and a respective pressure balance for setting a load-independent flow to the directional and speed controlling valve means, the pressure balance being subjected to a first pressure difference between the input and the output of the associated directional valve when the pump displacement is adequate and to a second lower pressure difference for reducing the flow when the pump displacement is inadequate, characterized in that the second pressure difference is generated by a pressure regulating valve controlled by the pump pressure and highest consumer pressure and provides a control pressure output led jointly to all the pressure balances.

Kreth, N.; Schmitt, M.; Stellwagen, A.

1988-04-26

185

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

186

Influence of Hydraulic Delay on the Composition Dynamics and Controller Design of Tray-Type Distillation Columns.  

Science.gov (United States)

It is shown that although the hydraulic delay transfer function cannot be reformed into diagonal form, the dynamic behavior of all elements of this matrix are still very near to that of a first order lag. A set of controllers for this system is designed u...

B. M. Zhou H. M. Wang J. B. Edwards

1983-01-01

187

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

188

Design and control of large hydraulic backfill pours  

Energy Technology Data Exchange (ETDEWEB)

This paper outlines the procedures to be followed for large, semi-continuous cemented or uncemented hydraulic backfill pours to ensure a minimum of delay in the mining sequence and provide the necessary control for safety purposes. The drainage requirements for given backfill material and site conditions can be readily calculated and hence adequate drainage facilities can be incorporated in the backfill and bulkhead designs. The analysis of the pressures acting at the base of large filled stopes indicates that free-draining bulkheads can be used in a majority of situations. Typical design calculations for poured reinforced concrete, free-draining timber and pervious concrete block bulkheads are presented. Operational control of pouring operations requires periodic checking of the input material properties, water balance measurements and solid plus water pressure measurements. Hydrostatic pressure cannot develop within a fill mass provided that the quantity of water flow from the exits is, at all times, equal to the quantity of water flow arriving at the base of a free-draining backfill. The use of filter blankets above any waste rock or slough in the restricted cone area and the use of fiber material in the drift plugs ensure adequate base and exit flow quantities. Solid and seepage pressures acting on a bulkhead can be estimated from the fill properties, the geometry of the stope void and the exits. Free-draining timber or concrete block bulkheads can be readily designed to provide an adequate factor of safety. These designs result in definite economic advantages over massive concrete bulkheads and reduce significantly the time between extraction and filling cycles. Significant deviations from expected performance can be readily identified and, in the limit, the necessary safety factor can be maintained by stopping the pour. If the procedures outlined are followed, there is no possibility of failure of a free-draining bulkhead.

Smith, J.D. (John D. Smith Engineering Associates Ltd., Kingston, Ontario); Mitchell, R.J.

1982-02-01

189

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.

2012-05-22

190

Logic Threshold Based Energy Control Strategy for Parallel Hydraulic Hybrid Vehicles  

Directory of Open Access Journals (Sweden)

Full Text Available To improve the performance of a Parallel Hydraulic Hybrid Vehicle (PHHV, the operation of components in the hydraulic hybrid system of the vehicle should be well coordinated. This study introduces an energy control strategy based on the logic threshold methodology for PHHVs. The energy distribution of the PHHV can be controlled in real-time and the operation modes of the PHHV can be changed dynamically by means of this energy control strategy. A simulation model for the analysis of the whole vehicle dynamic performance is developed using the Simulink in MATLAB. The multi-objective Genetic Algorithm (GA optimization method is employed to get the optimal working modes, the best energy distribution in different drive cycles and the optimal parameters of the control strategy. In this optimization, maximum fuel economy is the objective and the difference of engine optimal torque and active pressure torque and the pressure limit are the variables of the GA optimization. The simulation results show that the fuel economy of the PHHV can be improved and in addition, the dynamic performance of the vehicle can be enhanced with the proposed energy control strategy.

Liu-Tao

2013-08-01

191

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

192

Design of a hydraulic power take-off system for the wave energy device with an inverse pendulum  

Science.gov (United States)

This paper describes a dual-stroke acting hydraulic power take-off (PTO) system employed in the wave energy converter (WEC) with an inverse pendulum. The hydraulic PTO converts slow irregular reciprocating wave motions to relatively smooth, fast rotation of an electrical generator. The design of the hydraulic PTO system and its control are critical to maximize the generated power. A time domain simulation study and the laboratory experiment of the full-scale beach test are presented. The results of the simulation and laboratory experiments including their comparison at full-scale are also presented, which have validated the rationality of the design and the reliability of some key components of the prototype of the WEC with an inverse pendulum with the dual-stroke acting hydraulic PTO system.

Zhang, Da-hai; Li, Wei; Zhao, Hai-tao; Bao, Jing-wei; Lin, Yong-gang

2014-04-01

193

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

1994-01-01

194

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

195

A device for the hydraulic control of nuclear reactor control rods  

International Nuclear Information System (INIS)

A device for driving and locking the control rods of a nuclear reactor. This device comprises a hydraulic driving piston mounted in a cylinder provided with a construction for absorbing shocks. The piston is provided, at is extremity, with a locking device adapted to engage a stationary lock, it being possible to control the latter for freeing said piston locking device; with such an arrangement, the control rod is normally maintained in position, and it can be freed only by a positive signal. Moreover, the control rod movements are slowed down, so as to prevent the gripping device from being damaged. This device can be used in the nuclear industry

1973-06-06

196

Hydraulic characterisation of karst systems with man-made tracers  

International Nuclear Information System (INIS)

Tracer experiments using man-made tracers are common in hydrogeological exploration of groundwater aquifers in karst systems. In the present investigation, a convection-dispersion model (multidispersion model with consideration of several flow paths) and a single-cleft model (consideration of the diffusion between the cleft and the surrounding rock matrix) were used for evaluating tracer experiments in the main hydrological system of the saturated zone of karst systems. In addition to these extended analytical solutions, a numerical transport model was developed for investigating the influence of the transient flow rate on the flow and transport parameters. Comparative evaluations of the model approaches for the evaluation of tracer experiments were made in four different karst systems: Danube-Aach, Paderborn, Slowenia and Lurbach, of which the Danube-Aach system was considered as the most important. The investigation also comprised three supplementary experiments in order to enable a complete hydraulic characterisation of the system. (orig./SR)

1998-01-01

197

Project for Concentrated Research and Training in the Hydraulic and Hydrologic Aspects of Water Pollution Control.  

Science.gov (United States)

Contents: Project for concentrated research and training in the hydrologic and hydraulic aspects of water pollution control; Activities; Education and training aspects of center; Research accomplishments; Research accomplishments (projects not supported b...

P. A. Krenkel F. L. Parker

1969-01-01

198

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

199

Thermo-hydraulic analysis of the windowless target system  

International Nuclear Information System (INIS)

The target system, whose function is to supply an external neutron source to a subcritical core in order to sustain the neutron chain reaction, is the most critical part of an ADS being subject to severe thermo-mechanical loading and material damage due to accelerator protons and fission neutrons. In order to reduce the material damage and to increase the life of the target system a windowless option was chosen in the framework of the European PDS-XADS project as reference configuration for the experimental ADS cooled by lead-bismuth eutectic alloy. This document deals with the results of the thermo-hydraulic analysis performed with STAR-CD and RELAP5 codes to assess the behaviour of the windowless target system during off-normal operating conditions. It also reports a description of modifications properly implemented in the codes for studying this kind of plant. The windowless target system shows a satisfactory thermo-hydraulic behaviour for the analysed accidents, except for the loss of both pumps without proton beam shut-off and for the beam trips lasting more than 1 s

2008-08-01

200

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

 
 
 
 
201

Thermal and hydraulic analyses of the System 81 cold traps  

Energy Technology Data Exchange (ETDEWEB)

Thermal and hydraulic analyses of the System 81 Type I and II cold traps were completed except for thermal transients analysis. Results are evaluated, discussed, and reported. Analytical models were developed to determine the physical dimensions of the cold traps and to predict the performance. The FFTF cold trap crystallizer performances were simulated using the thermal model. This simulation shows that the analytical model developed predicts reasonably conservative temperatures. Pressure drop and sodium residence time calculations indicate that the present design will meet the requirements specified in the E-Specification. Steady state temperature data for the critical regions were generated to assess the magnitude of the thermal stress.

Kim, K.

1977-06-15

202

Hydraulic yaw system for a megawatt-scale wind turbine  

Energy Technology Data Exchange (ETDEWEB)

Large wind turbines experience large yaw moments, whilst the tower head dimensions do not necessarily increase in proportion. If the yaw bearing and mainframe width are kept fairly small for reasons of cost and transport, an exceptionally large number of yaw brakes and yaw drives will be required. In the course of the design of a two-bladed upwind wind turbine of 61 m diameter and 1.2 MW rated power for Autoflug Energietechnik GmbH and Co. KG, a hydraulic yaw system has been designed. It offers a cost reduction and some other advantages. (author)

Boehmeke, G. [Aerodyn Energiesysteme GmbH, Rendsburg (Germany)

1996-12-31

203

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.

2008-05-05

204

Hydrocone Crusher : A new fast robust design of the hydraulic system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This master thesis has been conducted at Sandvik Svedala. The thesis is the first step towards a new construction of a hydraulic system for a Hydrocone crusher. First we studied how contaminations entered the system of today. Then the work began with designing several concepts to control the crusher. These basic concepts were presented to Sandvik and the one was chosen for further development was fine tuned and a system was built. This system was tested at a test rig to verify that the basic ...

2008-01-01

205

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

206

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

207

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

Energy Technology Data Exchange (ETDEWEB)

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

Singla Font, S.

2005-07-01

208

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

209

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

210

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

211

Hydraulic support stability control of fully mechanized top coal caving face with steep coal seams based on instable critical angle  

Energy Technology Data Exchange (ETDEWEB)

The support instable mode of sliding, tripping, and so on was analysed. It was assumed that the key point of support stability control of fully mechanized coal caving face with steep coal seams was to maintain the seam true angle at less than the hydraulic support instability critical angle. Through the layout of oblique face, the improvement of support setting load, the control of mining height and nonskid platform, the group support system of end face, the advance optimization of conveyor and support, and the other control technical measures, the true angle of the seam is reduced and the instable critical angle of the support is increased. The hydraulic support stability of fully mechanized coal caving face with steep coal seams is effectively controlled. 6 refs., 2 figs., 2 tabs.

Tu, Shi-hao; Yuan, Yong; Li, Nai-liang; Dou, Feng-jin; Wang, Fang-tian [China University of Mining & Technology, Xuzhou (China). State Key Laboratory of Coal Resource and Mine Safety, School of Mining Engineering

2008-09-15

212

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

213

Fault Diagnosis of a Hydraulic Power System Using an Artificial Neural Network ????? ??????? ?? ?????? ???? ?????????? ???????? ??????? ??????? ??????????  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper deals with the problem of fault detection, isolation and identification of a hydraulic power system. A proposed fault diagnostic scheme (FDS) using an artificial neural network (ANN) is investigated. A feedforward neural network is employed to diagnose two commonly occurring faults of the hydraulic power system: actuator internal leakage and valve spool blockage. The characterizing model of each fault is derived. The fault diagnostic scheme is applied to a hydraulic power test rig ...

2006-01-01

214

Application of optical fiber sensing technology in the hydraulic decoking monitoring system  

Science.gov (United States)

On the basis of the analysis of the current hydraulic decoking monitoring system, it is proposed that use optical fiber Bragg grating (FBG) vibration sensor and fiber Fabry-Perot (FP) acoustic sensors to online monitor vibration signal and audio signal hydraulic of the coke drum in the running state progress, analysis the vibration sensor and acoustic sensor used in the system. Based on the actual monitoring results in Sinopec Wuhan Branch , the fiber optic acoustic emission sensors is more suitable for the hydraulic decoking online monitoring system than the FBG vibration sensor ,which can more accurate monitor of hydraulic decoking.

Fan, Yun-feng; Tong, Xing-lin; Ji, Tao; Gao, Xue-qing; Zhong, Dong

2013-09-01

215

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

216

Hydraulic manipulator research at ORNL  

International Nuclear Information System (INIS)

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

1997-05-01

217

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.

2012-11-26

218

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

1985-07-01

219

Thermal hydraulic test for core cooling system using steam generators  

International Nuclear Information System (INIS)

As a candidate of the new concept safety system for the next generation PWR in Japan, the hybrid safety systems, which are combination of the active and the passive safety systems, and passive core cooling system by natural circulation in the reactor coolant loop with horizontal-type steam generators during Loss of Coolant Accidents (LOCAs) are investigated. The passive safety systems are advanced accumulators (ACC), primary-side and secondary-side automatic-depressurization systems (ADS, SADS), and a gravity-driven safety injection system (GDI). The horizontal steam generator design avoids a siphon break caused from the accumulation of non-condensable gases in the tubes by using a vent line in the channel head of the steam generators. This study investigates the passive core cooling characteristics of horizontal-type steam generators under LOCAs. The integrated thermal-hydraulic test has been performed at the Simulation Loop for the Innovative Mitsubishi Simplified PWR (SLIM) test facility. The facility simulates the prototype plant with the volumetric scaling ratio of 1/1000 and the elevation scaling ratio of 1/1. Experimental results show good vent performance of non-condensable gasses. Furthermore, experiments also show that after a large LOCA steady natural circulation in the reactor coolant loop is resumed after the break portion is submerged. Sufficient core cooling for both small and large LOCA was also confirmed. (author)

1999-04-19

220

Hydraulic transient analysis for PWR auxiliary feedwater system  

International Nuclear Information System (INIS)

The Auxiliary Feed Water (AFW) system in a PWR plant is a safety related critical system, it provides cooling water to steam generators for removal of sensible heat to safely shut and cool down the reactor primary system when the main feedwater system is not available. The system in a Taiwan Power Company's PWR unit consists of two(2) motor driven and one(1) turbine pumps (AFWP) taking suctions from Condensate Storage Tank (CST) and discharging to three(3) steam generators through 929 feet piping and more than 73 valves. During early system pre-operational phase, the two(2) motor driven AFWPs were damaged after two(2) days continuous operation of the system. After investigation, interim fixes were taken and hydraulic transient analysis was performed to provide data and information for long term betterment of the systems and for operational reference. The transient analysis was based on the characteristic method, using the computer programs, HYTRAN, developed by Taipower engineers (Messrs: HH Lee and WC Lin). The accuracy of the HYTRAN was bench marked by comparison with the transient test data of the system and by comparison with comparable computer programs. The comparison with the test data showed close equivalence of the analysis data and the test data. This paper highlights the transient analysis method with detail descriptions of the equipment modelling techniques of the system and components. Both the analysis and test results 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)

1986-01-01

 
 
 
 
221

Hydraulic Performance of a Downstream Controlled Irrigation Canal equipped with Difeerent Offtake Types  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Regarding canal management modernization, water savings and water delivery quality, the study presents two automatic canal control approaches of the PI (Proportional and Integral) type: the distant and the local downstream control modes. The two PI controllers are defined, tuned and tested using a hydraulic unsteady flow simulation model, particularly suitable for canal control studies. The PI control parameters are tuned using optimization tools. The simulations are done for a Portuguese pro...

Rijo, Manuel; Arranja, Carina

2005-01-01

222

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

223

Keeping hydraulic fluid clean  

Energy Technology Data Exchange (ETDEWEB)

Overall, fluid power is one of the most reliable and repeatable forms of motion control. However, failures do occur. Recent research has found that the root cause of many hydraulic component and system failures is fluid contamination and inadequate contamination control practices. Preventing unplanned downtime through systemic contamination control and proactive or predictive maintenance is an effective strategy that significantly reduces problems. Understanding the principles involved assist the plant engineer, machine operators, and maintenance personnel in economically achieving maximum hydraulic system life and minimum downtime. The paper discusses the sources of contamination, contamination damage, systematic contamination control, filters, and filter location.

Downs, D.C. [Vickers, Inc., Maumee, OH (United States)

1997-03-01

224

Research on hydraulic system of KZC-5 type rear dump truck in underground mine  

International Nuclear Information System (INIS)

KZC-5 type rear dump truck in underground mine is introduced in this paper. The determining principles and ways of two main hydraulic systems are discussed. It has been proved that the hydraulic systems are reasonable in the industrial scale test. (author)

2005-05-01

225

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 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

1990-01-01

226

Control rod control system  

International Nuclear Information System (INIS)

A system for controlling a nuclear reactor is described comprising a nuclear core comprising fissile fuel elements having openings therebetween, control rods containing a neutron absorbing material arranged throughout the core and fitting within the openings between the fuel elements. The control rods are movably insertable and withdrawable from the openings by drive means comprising linear motion apparatus having lift, movable gripper and stationary gripper solenoid coils. The control rods are arranged in groups of a predetermined number of control rods which predetermined number move together, means for directing the movement of the groups of control rods to control the core radial power distribution and the core axial power distribution and means for sharing the power circuitry among the control rod groups, the power circuitry being connected to the drive mechanism of each group of control rods, the means for sharing the power circuitry comprising storage enclosures, with one enclosure containing the power circuitry for the lift and movable gripper coils for all of the groups of control rods in combination with separate enclosures which contain the power circuitry for the stationary gripper coils for each respective group of control rods

1988-01-01

227

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)

2005-01-01

228

Development of an Advanced Hydraulic Fracture Mapping System  

Energy Technology Data Exchange (ETDEWEB)

The project to develop an advanced hydraulic fracture mapping system consisted of both hardware and analysis components in an effort to build, field, and analyze combined data from tiltmeter and microseismic arrays. The hardware sections of the project included: (1) the building of new tiltmeter housings with feedthroughs for use in conjunction with a microseismic array, (2) the development of a means to use separate telemetry systems for the tilt and microseismic arrays, and (3) the selection and fabrication of an accelerometer sensor system to improve signal-to-noise ratios. The analysis sections of the project included a joint inversion for analysis and interpretation of combined tiltmeter and microseismic data and improved methods for extracting slippage planes and other reservoir information from the microseisms. In addition, testing was performed at various steps in the process to assess the data quality and problems/issues that arose during various parts of the project. A prototype array was successfully tested and a full array is now being fabricated for industrial use.

Norm Warpinski; Steve Wolhart; Larry Griffin; Eric Davis

2007-01-31

229

Design of an Electro-Hydraulic System Using Neuro-Fuzzy Techniques  

CERN Multimedia

Increasing demands in performance and quality make drive systems fundamental parts in the progressive automation of industrial processes. Their conventional models become inappropriate and have limited scope if one requires a precise and fast performance. So, it is important to incorporate learning capabilities into drive systems in such a way that they improve their accuracy in realtime, becoming more autonomous agents with some degree of intelligence. To investigate this challenge, this chapter presents the development of a learning control system that uses neuro-fuzzy techniques in the design of a tracking controller to an experimental electro-hydraulic actuator. We begin the chapter by presenting the neuro-fuzzy modeling process of the actuator. This part surveys the learning algorithm, describes the laboratorial system, and presents the modeling steps as the choice of actuator representative variables, the acquisition of training and testing data sets, and the acquisition of the neuro-fuzzy inverse-model...

Branco, P J C

2000-01-01

230

Evaluation of Army Engine Oils in Hydraulic/Power Transmission System Components.  

Science.gov (United States)

The objective of the MACI Hydraulic System and Components Program is to perform technical evaluation and assessment of commerically available qualified and fielded Army engine oils and to determine if such oils can be used as hydraulic fluids in Army comm...

H. W. Marbach S. J. Lestz

1985-01-01

231

Chapter 2. Mode-switching in Hydraulic Actuator Systems - An Experiment  

DEFF Research Database (Denmark)

Experiments with mode-switching adaptive control of actuators to drive a hydraulic test robot.The research is a cooperation with IT, DTU within the IMCIA Research Programme supported by the Danish Technical Research Council, STVF.

Andersen, Torben Ole; Conrad, Finn

1996-01-01

232

High Bulk Modulus of Ionic Liquid and Effects on Performance of Hydraulic System  

Science.gov (United States)

Over recent years ionic liquids have gained in importance, causing a growing number of scientists and engineers to investigate possible applications for these liquids because of their unique physical and chemical properties. Their outstanding advantages such as nonflammable liquid within a broad liquid range, high thermal, mechanical, and chemical stabilities, low solubility for gases, attractive tribological properties (lubrication), and very low compressibility, and so forth, make them more interesting for applications in mechanical engineering, offering great potential for new innovative processes, and also as a novel hydraulic fluid. This paper focuses on the outstanding compressibility properties of ionic liquid EMIM-EtSO4, a very important physical chemically property when IL is used as a hydraulic fluid. This very low compressibility (respectively, very high Bulk modulus), compared to the classical hydraulic mineral oils or the non-flammable HFDU type of hydraulic fluids, opens up new possibilities regarding its usage within hydraulic systems with increased dynamics, respectively, systems' dynamic responses.

Kalb, Roland; Tasner, Tadej

2014-01-01

233

Engineered Barrier Systems Thermal-Hydraulic-Chemical Column Test Report  

Energy Technology Data Exchange (ETDEWEB)

The Engineered Barrier System (EBS) Thermal-Hydraulic-Chemical (THC) Column Tests provide data needed for model validation. The EBS Degradation, Flow, and Transport Process Modeling Report (PMR) will be based on supporting models for in-drift THC coupled processes, and the in-drift physical and chemical environment. These models describe the complex chemical interaction of EBS materials, including granular materials, with the thermal and hydrologic conditions that will be present in the repository emplacement drifts. Of particular interest are the coupled processes that result in mineral and salt dissolution/precipitation in the EBS environment. Test data are needed for thermal, hydrologic, and geochemical model validation and to support selection of introduced materials (CRWMS M&O 1999c). These column tests evaluated granular crushed tuff as potential invert ballast or backfill material, under accelerated thermal and hydrologic environments. The objectives of the THC column testing are to: (1) Characterize THC coupled processes that could affect performance of EBS components, particularly the magnitude of permeability reduction (increases or decreases), the nature of minerals produced, and chemical fractionation (i.e., concentrative separation of salts and minerals due to boiling-point elevation). (2) Generate data for validating THC predictive models that will support the EBS Degradation, Flow, and Transport PMR, Rev. 01.

W.E. Lowry

2001-12-13

234

Tractor Hydraulics. A Teaching Reference.  

Science.gov (United States)

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

American Association for Vocational Instructional Materials, Athens, GA.

235

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

International Nuclear Information System (INIS)

In July, 1989, the U. S. Nuclear Regulatory Commission issued Generic Letter 89-13, open-quotes Service Water Problems Affecting Safety-Related Equipmentclose quotes. The Generic Letter was issued because of observed operating problems with corrosion, erosion, biological fouling, silting, and protective coating failure in safety-related heat exchangers and associated cooling water piping at several nuclear power plants. The NRC required that utilities with operating nuclear plants establish a plan for comprehensive evaluation of their open cycle Service Water Systems, including: ongoing surveillance and control; testing of safety-related heat exchangers to verify heat transfer capability; inspection and maintenance of piping and water-cooled heat exchangers; confirmation that the service water system is capable of performing its intended function in accordance with the plant design basis; confirmation that maintenance and operating practices, emergency procedures, and training are adequate to ensure that safety-related equipment will perform as intended. As an integral part of the Georgia Power Company response to the Generic Letter, a personal computer-based hydraulic flow model was developed for the Plant Service Water Systems (PSW) on both units of the E. I. Hatch Nuclear Plant (HNP). The Bechtel-developed BALANCE program and PLANTSIM option were selected for this effort. Bechtel's hydraulic network computer program was developed 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

1993-04-13

236

Active control of static pressure drop caused by hydraulic servo-actuator engage  

Energy Technology Data Exchange (ETDEWEB)

Pressure drop caused by propagation of expansion waves in the source pipeline of fast high cyclic hydraulic actuator produces possible anomalies in its function. To prevent pressure drop it is possible to minimize wave effects by active control of actuator servo-valve throttle leakage. In the paper is presented synthesis of possible discrete active control of hydraulic actuator and its servo-valve for prevention expansion wave pressure drop. Control synthesis is based on static pressure increasing with decreasing of fluid flow velocity, which can be realized by lower throttle leakage. Some of the effects of assumed control are shown on corresponding diagrams of control valve throttle motion, piston displacement and its corresponding linear velocity.

Janlovic, J. [Univ. of Belgrade (Yugoslavia)

1994-12-31

237

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

238

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Xiyun Yang; Jinxia Li; Wei Liu; Peng Guo

2011-01-01

239

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

International Nuclear Information System (INIS)

The present research aims at the development of the thermal hydraulic verification test technology for the safety system of the conventional and advanced nuclear power plant and the development of the advanced thermal hydraulic measuring techniques. In this research, test facilities simulating the primary coolant system and safety system are being constructed for the design verification tests of the existing and advanced nuclear power plant. 97 figs, 14 tabs, 65 refs. (Author)

1995-01-01

240

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

 
 
 
 
241

French code system for a sodium cooled LMR inter-assembly thermal hydraulic analysis  

Energy Technology Data Exchange (ETDEWEB)

Sodium cooled LMR core is generally comprised of many ducted assemblies which have no flow exchanges between them. So, the required flow to each assembly corresponding to its power has to be allocated in thermal hydraulic design. Flow allocation facility, which is called orifice, is used for this purpose in an LMR core. In this context, flow grouping, assembly subchannel analysis and inter-assembly flow analysis have to be done in the LMR core thermal hydraulic design and analysis. This report describes this sodium cooled LMR core thermal hydraulic design procedure, in which are flow grouping, subchannel analysis and inter-assembly whole core analysis. And the French whole core analysis code system is described which is used for the domestic whole core thermal hydraulic analysis code system development. Firstly, sodium cooled LMR core thermal hydraulic conceptual design and analysis procedure is explained in chapter 2. Chapter 3 overviews the necessity and methodology of the whole core thermal hydraulic analysis, and the French whole core analysis system is described in chapter 4. Chapter 5 describes the domestic plan of the inter-assembly thermal hydraulic analysis system, and chapter 6 shows the conclusion and the future works.

Kim, Young-Gyun; Lim, Hyun-Jin; Kim, Young-Il

2005-03-01

242

French code system for a sodium cooled LMR inter-assembly thermal hydraulic analysis  

International Nuclear Information System (INIS)

Sodium cooled LMR core is generally comprised of many ducted assemblies which have no flow exchanges between them. So, the required flow to each assembly corresponding to its power has to be allocated in thermal hydraulic design. Flow allocation facility, which is called orifice, is used for this purpose in an LMR core. In this context, flow grouping, assembly subchannel analysis and inter-assembly flow analysis have to be done in the LMR core thermal hydraulic design and analysis. This report describes this sodium cooled LMR core thermal hydraulic design procedure, in which are flow grouping, subchannel analysis and inter-assembly whole core analysis. And the French whole core analysis code system is described which is used for the domestic whole core thermal hydraulic analysis code system development. Firstly, sodium cooled LMR core thermal hydraulic conceptual design and analysis procedure is explained in chapter 2. Chapter 3 overviews the necessity and methodology of the whole core thermal hydraulic analysis, and the French whole core analysis system is described in chapter 4. Chapter 5 describes the domestic plan of the inter-assembly thermal hydraulic analysis system, and chapter 6 shows the conclusion and the future works

2005-01-01

243

Hydraulic turbines  

International Nuclear Information System (INIS)

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

1998-01-01

244

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.

245

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)

1990-10-22

246

The Effect of Fluid Contamination on the Operating Reliability of Aircraft Hydraulic Systems.  

Science.gov (United States)

The report contains investigation results and generalized literature data regarding the effects of contamination of working fluids on operating reliability of units of hydraulic aircraft systems. Methods are analyzed for determination of contamination. Da...

G. A. Nikitin S. V. Chirkov

1970-01-01

247

Decoupling analysis for a powertrain mounting system with a combination of hydraulic mounts  

Science.gov (United States)

The existing torque roll axis(TRA) decoupling theories for a powertrain mounting system assume that the stiffness and viscous damping properties are constant. However, real-life mounts exhibit considerable spectrally varying stiffness and damping characteristics, and the influence of the spectrally-varying properties of the hydraulic mounts on the powertrain system cannot be ignored. To overcome the deficiency, an analytical quasi-linear model of the hydraulic mount and the coupled properties of the powertrain and hydraulic mounts system are formulated. The influence of the hydraulic mounts on the TRA decoupling of a powertrain system is analytically examined in terms of eigensolutions, frequency, and impulse responses, and then a new analytical axiom is proposed based on the TRA decoupling indices. With the experimental setup of a fixed decoupler hydraulic mount in the context of non-resonant dynamic stiffness testing procedure, the quasi-linear model of the hydraulic mount is verified by comparing the predictions with the measurement. And the quasi-linear formulation of the coupled system is also verified by comparing the frequency responses with the numerical results obtained by the direct inversion method. Finally, the mounting system with a combination of hydraulic mounts is redesigned in terms of the stiffness, damping and mount locations by satisfying the new axiom. The frequency and time domain results of the redesigned system demonstrate that the torque roll axis of the redesigned powertrain mounting system is indeed decoupled in the presence of hydraulic mounts (given oscillating torque or impulsive torque excitation). The proposed research provides an important basis and method for the research on a powertrain system with spectrally-varying mount properties, especially for the TRA decoupling.

Hu, Jinfang; Chen, Wuwei; Huang, He

2013-07-01

248

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

249

Electromotive/hydraulic pressure type reactor control rod drives  

International Nuclear Information System (INIS)

The mechanism of the present invention can detect an abnormality of a shock absorbing mechanism by utilizing a detection mechanism for control rod fuel insertion position upon scram without deteriorating the essential function. That is, a stopper is disposed between upper and lower two structural members of the shock absorbing mechanism for restricting relative movement in the direction of parting both of the structural members. With such a constitution, if the upper structural members should be sticked and a flush spring is kept to be compressed, the lower structural member can not protrude downward relative to the upper structural member by an effect of the stopper. Accordingly, when a piston and a control rod are extracted by an electric motor after completion of scram, although a control rod position signal of a rotation detector is changed, full insertion signal is continued to be saved from a magnetic sensor. Accordingly, if the state of both of the signals is distinguished, abnormalities of the shock absorbing mechanism can be detected. (I.S.)

1991-06-17

250

Multi-parameter monitoring system for hydraulic fluids; Multi-Parameter Monitoring System fuer Hydraulische Fluessigkeiten  

Energy Technology Data Exchange (ETDEWEB)

A miniaturised sensor system for aviation hydraulic fluids is presented. The system consists of an optochemical sensor and a particle sensor. The optochemical sensor detects the form of the O-H absorption feature around 3500 cm{sup -1} to reveal the water and acid contamination in the fluid. The particle sensor uses a light barrier principle to derive its particle contamination number. (orig.)

Paul, Sumit; Legner, Wolfgang; Hackner, Angelika; Mueller, Gerhard [EADS Innovation Works, Muenchen (Germany). Bereich Sensors, Electronics and Systems Integration; Baumbach, Volker [Airbus Operations GmbH, Bremen (Germany). Bereich Hydraulic Performance and Integrity

2011-07-01

251

Development of MARS for multi-dimensional and multi-purpose thermal-hydraulic system analysis  

International Nuclear Information System (INIS)

MARS (Multi-dimensional Analysis of Reactor Safety) code is being developed by KAERI for the realistic thermal-hydraulic simulation of light water reactor system transients. MARS 1.4 has been developed as a final version of basic code frame for the multi-dimensional analysis of system thermal-hydraulics. Since MARS 1.3, MARS 1.4 has been improved to have the enhanced code capability and user friendliness through the unification of input/output features, code models and code functions, and through the code modernization. Further improvements of thermal-hydraulic models, numerical method and user friendliness are being carried out for the enhanced code accuracy. As a multi-purpose safety analysis code system, a coupled analysis system, MARS/MASTER/CONTEMPT, has been developed using multiple DLL (Dynamic Link Library) techniques of Windows system. This code system enables the coupled, that is, more realistic analysis of multi-dimensional thermal-hydraulics (MARS 2.0), three-dimensional core kinetics (MASTER) and containment thermal-hydraulics (CONTEMPT). This paper discusses the MARS development program, and the developmental progress of the MARS 1.4 and the MARS/MASTER/CONTEMPT focusing on major features of the codes and their verification. It also discusses thermal hydraulic models and new code features under development. (author)

2000-10-01

252

Steam-Hydraulic Turbines Load Frequency Controller Based on Fuzzy Logic Control  

Directory of Open Access Journals (Sweden)

Full Text Available This study investigates an application of the fuzzy logic technique for designing the load-frequency control system to damp the frequency and tie line power oscillations due to different load disturbances under the governor deadzones and GRC non-linearity. Integral controller are designed and compared with the proposed fuzzy logic controller. To validate the effectiveness of the proposed controller, two-area load frequency power system is simulated over a wide range of operating conditions and system parameter changes. Further, comparative studies between the conventional PID control and proposed efficient fuzzy logic load frequency control are included on the simulation results. Programs Matlab software are developed for simulation. The digital results prove the power of the present fuzzy load-frequency controller over the conventional. PID controller in terms of fast response with less overshoot and small settling time.

Ali M. Yousef

2012-08-01

253

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

1980-01-01

254

A conceptual model of check dam hydraulics for gully control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

There is little information in scientific literature regarding the modifications induced by check dam systems in flow regimes in restored gully reaches, despite it being a crucial issue for the design of conservation measures. Here, we develop a conceptual model to classify flow regimes in straight rectangular channels for initial and dam-filling conditions as well as a method of estimating efficiency in order to provide guidelines for optimal design. The model integrates several previous mat...

Castillo, C.; Pe?rez, R.; Go?mez, J. A.

2013-01-01

255

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

256

Application of flow network models of SINDA/FLUINTTM to a nuclear power plant system thermal hydraulic code  

International Nuclear Information System (INIS)

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/FLUINTTM 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)

1998-05-01

257

Modelling and Control of a Complementary Energy Recuperation System for Mobile Working Machines  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The concept of hybrid technologies for mobile working machines has gained increased attention in recent years. This paper deals with a parallel hybrid system for energy recuperation based on a two-machine hydraulic transformer. The system can be connected hydraulically to an existing hydraulic circuit as a complementary add-on system. The linear analysis of the system visualises the control difficulties coming from a low inertia, slow control dynamics of the machines and the non-linear stick-...

Hugo, Anton; Pettersson, Karl; Heybroek, Kim; Krus, Petter

2013-01-01

258

Vehicular automatic transmission control system  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a vehicular automatic transmission control system. The control system consists of: a hydraulic control circuit including a hydraulic pressure source, a pressure regulator valve for producing a line pressure by regulating the oil pressure supplied from the pressure source, a number of shift valves for selectively engaging and releasing friction members of the automatic transmission according to operating conditions of a vehicle such as vehicle speed and throttle opening rate, and a solenoid valve blocking switching operation of a highest shift valve toward a highest gear position of the transmission; an electronic control circuit for controlling on- and off- ranges of the solenoid valve, including a manual mode switch, which is a momentary switch, for setting the control of the automatic transmission either in a highest gear non-cancel mode permitting shifts to the highest gear position or in a highest gear cancel mode inhibiting shifts to the highest gear position and forcibly effecting a downshift when selected during operation in the highest gear position, a vehicle speed sensor, and a kickdown switch detecting a throttle opening rate greater than a predetermined value; a frequency divider for inputting outputs of the manual switch.

Kondo, H.

1989-05-30

259

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

1992-01-01

260

Crosshole investigations - Details of the construction and operation of the hydraulic testing system  

International Nuclear Information System (INIS)

The Crosshole Programme, part of the international Stripa Project is designed to evaluate the effectiveness of various remote-sensing techniques in characterizing a rock mass around a repository. A multidisciplinary approach has been adopted in which various geophysical, mapping and hydrogeological methods are used to determine the location and characteristics of significant features in the rock. The Programme utilises six boreholes drilled in a fan array from the 360 metre level in the Stripa Mine, Sweden. The hydrogeological component of the work uses single and crosshole testing methods, including sinusoidal pressure testing, to locate fractures and characterize groundwater movement within them. Crosshole methods use packers to isolate portions of two boreholes which both intersect a significant feature in the rock mass. Hydraulic signals are generated in one isolated section and received in the other borehole. This report describes the design and operation of the computer-controlled system which automatically performs the hydrogeological tests. (authors)

1986-01-01

 
 
 
 
261

Interface For Fault-Tolerant Control System  

Science.gov (United States)

Interface unit and controller emulator developed for research on electronic helicopter-flight-control systems equipped with artificial intelligence. Interface unit interrupt-driven system designed to link microprocessor-based, quadruply-redundant, asynchronous, ultra-reliable, fault-tolerant control system (controller) with electronic servocontrol unit that controls set of hydraulic actuators. Receives digital feedforward messages from, and transmits digital feedback messages to, controller through differential signal lines or fiber-optic cables (thus far only differential signal lines have been used). Analog signals transmitted to and from servocontrol unit via coaxial cables.

Shaver, Charles; Williamson, Michael

1989-01-01

262

Coupled 3D hydrodynamic models for submarine outfalls. Denvironmental hydraulic design and control of multiport diffusers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The book describes the hydraulic design and environmental impact prediction technologies for such installations. Focus are the hydrodynamics approached by computer models. First, a multiport diffuser design program was developed. Second, two model systems for discharge analysis, CORMIX for the near-field and intermediate-field and Delft3D for the far-field were coupled, and third a regulatory procedure is proposed to license and monitor outfall installations.

Bleninger, Tobias

2007-01-01

263

The Control System Modeling and The Mechanical Structure Analysis For EMCVT  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The current automotive metallic belt continuously variable transmission (CVT) mostly use hydraulic system to push the cone disc and achieve the speed ratio control. A new Electrical Mechanical Continuously Variable Transmission without hydraulic control (Electrical Mechanical CVT, EMCVT) studied in this paper, uses the rolling screw mechanism to press cone disc, achieves speed regulation through the electronic control mechanism, and abandons the energy-intensive hydraulic system. In this pape...

Zhang, Lei; Cong, Xiaomei; Hujian Pan; Cai, Zuge; Yang, Xiumin

2013-01-01

264

Thermal-hydraulic analysis of the Fort St. Vrain modular vault dry store system  

International Nuclear Information System (INIS)

This paper reports on a passive, natural thermosyphon, air-cooled modular vault dry store (MVDS) system that is being constructed for the storage of nuclear spent fuel for the Fort St. Vrain (FSV) Nuclear Power Station. In support of this FSV-MVDS system, thermal-hydraulic design analyses have been performed. The objective of the analyses is to determine flow and temperature distributions within the system and thus to ensure that the maximum fuel element temperatures shall not exceed specified design limit values under various loading and unloading conditions. This paper presents the method of analysis and discusses the resulting thermal-hydraulic characteristics of the MVDS system

1991-01-01

265

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

1993-04-25

266

Final design of a free-piston hydraulic advanced Stirling conversion system  

Science.gov (United States)

Under the US Department of Energy's (DOEs) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for solar distributed receiver systems. The final design is described of an engineering prototype advanced Stirling conversion system (ASCS) with a free-piston hydraulic engine output capable of delivering about 25 kW of electric power to a utility grid. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, has noncontacting bearings, and can be hermetically sealed. The ASCS is designed to deliver maximum power per year over a range of solar input with a design life of 30 years (60,000 h). The system includes a liquid Nak pool boiler heat transport system and a free-piston Stirling engine with high-pressure hydraulic output, coupled with a bent axis variable displacement hydraulic motor and a rotary induction generator.

Wallace, D. A.; Noble, J. E.; Emigh, S. G.; Ross, B. A.; Lehmann, G. A.

1991-01-01

267

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 80ºC, 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

268

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

269

East integrated control system  

International Nuclear Information System (INIS)

EAST control system has been developed as network-based distributed control system composed of several subsystems. The integrated control system includes a supervisory control system, many local control systems, machine control and safety interlocks, data acquisition and management. The discharge control system, which is implemented in part of the CODAC (COntrol, Data Access and Communication) system, performs the discharge sequence execution. The development of the EAST integrated control system and commissioning results is presented in this paper.

2010-07-01

270

Hydraulic Plant Remote Laboratory  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper we present a three tank hydraulic system and possibilities how it can be used for the purpose of remote laboratories. The concept of our remote laboratory is based on client – server architecture. We compare two different approaches of remote control. First one uses a Java Server application implemented together with a control algorithm on the server side. In this case the control algorithm is realized in the Matlab/Simulink environment. There is necessary to exchange data bet...

Vladimir Zilka; Pavol Bisták; Peter Kurcik

2008-01-01

271

Design and testing of the reactor-internal hydraulic control rod drive for the nuclear heating plant  

International Nuclear Information System (INIS)

A hydraulically driven control rod is being developed at Kraftwerk Union for integration in the primary system of a small nuclear district heating reactor. An elaborate test program, under way for --3 yr, was initiated with a plexiglass rig to understand the basic principles. A design specification list was prepared, taking reactor boundary conditions and relevant German rules and regulations into account. Subsequently, an atmospheric loop for testing of components at 20 to 900C was erected. The objectives involved optimization of individual components such as a piston/cylinder drive unit, electromagnetic valves, and an ultrasonic position indication system as well as verification of computer codes. Based on the results obtained, full-scale components were designed and fabricated for a prototype test rig, which is currently in operation. Thus far, all atmospheric tests in this rig have been completed. Investigations under reactor temperature and pressure, followed by endurance tests, are under way. All tests to date have shown a reliable functioning of the hydraulic drive, including a novel ultrasonic position indication system

1987-01-01

272

Analysis of the flow dynamics in the multiloop thermal-hydraulic system  

International Nuclear Information System (INIS)

The method for identification of the closed loops in the thermal-hydraulics system is described. The mathematical models, previously developed for the single loop system, have been extended to treat multiloop pipelines. The configuration of the network is practically deliberate. The model has been tested by the simulation of the asymmetric transient in the two loop PWR. (author)

1989-06-12

273

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

274

Climatic controls on soil hydraulic properties along soil chronosequences on volcanic parent material  

Science.gov (United States)

Soil development is influenced by physical and chemical weathering processes and accumulation of eolian sediment. These weathering processes have often been examined using chronosequences that take advantage of deposited lava flows ranging in age. These studies typically characterize the physical and sometimes chemical properties, but rarely have these studies examined how hydraulic properties change with time. In addition, many of these studies occur in tropical climates where weathering occurs rapidly; relatively little is known about weathering processes in cool dry climates. This is important not only to understand how water and energy move in these water limited systems, but also to understand how they might change as climate patterns shift. The objectives of this research were to 1) measure and model the soil water retention, ?(h), and hydraulic conductivity, K(h), functions across a chronosequence of cinder cone sites in a cold desert region, 2) compare soil hydraulic properties across soil ages to examine how soil development in semi-arid climates moderates soil hydraulic processes, and 3) compare soil hydraulic characteristics in a dryland environment to those of a wet tropical climate across similarly aged lava flows. We contrast 2.1, 6.9 and 13.9 ka cinder cones soils at Craters of the Moon (COTM) National Monument, Idaho, USA. Soil development at COTM is sparse and is concentrated in joints and crevices of the basalt. The soils contrast slightly in texture with age. The young (2.1 ka) soils are coarser grained with at least 20% greater sand content than the older (6.9, 13.9 ka) soils. Preliminary hydraulic modeling suggests that older soils have lower ? values than younger soils. This is likely due to a higher bulk density values from higher accumulations of secondary minerals in the old soils from loess input. The models show that the air entry points (?) occur at lower tensions in the young soils, likely caused by a greater pore size distribution. We observe that ? decreases with age, and ? occurs at higher tensions. Soil horizons are developed dominantly on the cinder cones. These model estimates appear to match well with preliminary field measurements. Tropical climates enhance the weathering of basaltic parent material. The mean annual precipitation in the Hawaiian site is 2500 mm, and 310 mm at COTM. Accumulation of rainfall increases the weathering rate of the parent material. Using previous work characterizing the physical characteristics of soil across the Hawaii chronosequence to model the contrasting soils, we found that the 0.3 and 20 ka Hawaii soils had similar hydraulic properties; ? values were approximately 0.45 cm3/cm3 and Ks values were 6 cm/hr. However, these Hawaiian soils contrasted and were quantitatively lower than the entire COTM chronosequence. At the 2.1 ka COTM soil, Ks was 17 cm/hr and ? was 0.52-0.65 cm3/cm3 whereas at the 13.9 ka soil, Ks was 12 cm/hr and ? was 0.52 cm3/cm3. The 0.3 ka Hawaiian soil had a 20-30% higher silt content than the 2.1 ka COTM soil. Our models help quantify rates of soil development and hydraulic properties developed through time on volcanic parent materials.

Beal, L. K.; Lohse, K. A.; Godsey, S.; Huber, D. P.

2013-12-01

275

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

276

Open upper plenum of LOF thermal hydraulics and inherent control rod insertion  

International Nuclear Information System (INIS)

In liquid-metal reactor (LMR) hypothetical transients for which normal scram is postulated not to occur, the thermal expansion of the control rod drivelines (CRDs) as they are washed by the hotter core effluent tends to insert the control assemblies (CAs) further into the core, thereby providing negative reactivity. A number of concepts to enhance the heatup-induced elongation of drivelines is being proposed involving both design features of the drivelines as well as flow control features of the drivelines and the upper internals structure (UIS). Reported here are the results of an analysis in which the COMMIX-1A computer code was used to investigate the three-dimensional thermal-hydraulic behavior in the upper plenum of a 425-MW(t) pool-type LMR during a loss-of-flow (LOF) transient and its influence on the driveline heatup and expansion. The calculations consider an open plenum geometry, which does not incorporate a UIS or CRD shroud tubes such that the drivelines are directly exposed to the multidimensional plenum flow. The objective of the present work is to define reference cases for inherent CRD insertion in which thermal-hydraulic features that might enhance the driveline heatup but, on the other hand, whose effects may be quantitatively sensitive to design details are completely absent

1986-06-15

277

Control system for a continuously variable transmission  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a control system for a continuously variable belt-drive transmission having a selector device including a drive range position, a drive pulley having a hydraulically shiftable disc and a servo chamber for shifting the disc, a driven pulley having a hydraulically shiftable disc and a servo chamber for shifting the disc, and a belt engaged with both the pulleys, an hydraulic control circuit for supplying oil to the servo chambers and for draining the servo chambers, the hydraulic control circuit being provided with a pressure regulator valve for providing a line pressure and a transmission ratio control valve for applying the line pressure to the servo chamber of the drive pulley. The improvement comprises: a first drain passage from the pressure regulator valve; a second drain passage from the transmission ratio control valve; a first check valve provided in the first drain passage and a second check valve provided in the second drain passage for building up supplementary low pressure in both drain passages at upstream of both the check valves; a supplementary oil passage communicating both the first and second drain passages at upstream of the check valves for supplying a part of drain oil to the servo chamber of the drive pulley.

Sakai, Y.

1987-11-03

278

Study of the performance of four repairing material systems for hydraulic structures of concrete dams  

Directory of Open Access Journals (Sweden)

Full Text Available Four types of repairing materials are studied as function of either a conventional concrete or a reference-concrete (RefC, these are: polymer-modified cement mortar (PMor, steel fiber concrete (SFco, epoxy mortar (EMor and silica fume mortar (SFmo, to be applied in hydraulic structures surfaces subjected to a high velocity water flow. Besides the mechanical requests and wearing resistance of hydraulic concrete dam structures, especially the spillway surfaces, the high solar radiation, the environmental temperature and wet and dry cycles, contribute significantly to the reduction of their lifespan. RefC and the SFco were developed based on a usual concrete mixture used in slabs of spillways. The average RefC mixture used was 1: 1.61: 2.99: 0.376, with Pozzolan-modified Portland cement consumption of 425 kg/m³. EMor and PMor mixtures followed the information given by the manufacturers and lab experience. Tests on concrete samples were carried out in laboratory simulating normally found environmental situations in order to control the mechanical resistance and the aging imposed conditions, such as solar radiation and humidity. Also, physicochemical characterizing tests were made for all used materials. From the analyzed results, two of them presented a higher performance: the EMor and SFmo. SFco presented good adherence to the RefC and good mechanical performance. However, it also presented apparent metal corrosion in humidity tests, being indicated for use, with caution, as an intermediate layer in underwater repairs. In a general classification, considering all tests, including their field applications, the better performance material systems were EMor- SFmo> SFco> PMor.

Kormann A. C. M.

2003-01-01

279

Comparison of thermal-hydraulic safety codes for PWR systems  

International Nuclear Information System (INIS)

This state of the art report is concerned with thermal-hydraulic phenomena on the primary and secondary side of PWRs. It is addressed to engineers and scientists who would like to improve their knowledge of the models and the phenomena description, which exists in the different codes. It should also be of interest for persons who need an overview on existing codes. The selected codes are ALMOD (Federal Republic of Germany), CATHARE (France), DRUFAN/FLUT (FRG), RELAP5/MOD 2 (USA), THYDE P2 (Japan), TRACPF1/MOD 1 (USA). The report is divided into two parts. The first part presents code by code, with a common structure, all relevant information (such as structure, physical models, numerical solution schemes, etc.). The second part is devoted to a systematic comparison of main features, corresponding to the structure of the code description in Part 1, and also to quantitative comparisons concerning some important specific phenomena such as interfacial friction and mass transfer, and structure to fluid heat transfer. (author)

1988-01-01

280

Mechanical Engineering Design Project report: Enabler control systems  

Science.gov (United States)

The Controls Group was assigned the responsibility for designing the Enabler's control system. The requirement for the design was that the control system must provide a simple user interface to control the boom articulation joints, chassis articulation joints, and the wheel drive. The system required controlling hydraulic motors on the Enabler by implementing 8-bit microprocessor boards. In addition, feedback to evaluate positions and velocities must be interfaced to provide the operator with confirmation as well as control.

Cullen, Christian; Delvecchio, Dave; Scarborough, Alan; Havics, Andrew A.

1992-01-01

 
 
 
 
281

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

International Nuclear Information System (INIS)

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

2007-01-01

282

Practical experience of the main primary system hydraulic tests for Qinshan NPP phase II  

International Nuclear Information System (INIS)

Initial hydraulic test during commissioning and test renewal during refueling outage were performed once for unit 1 and 2 of Qinshan II respectively, all safety class 1 pressure-retaining components were subjected to 22.8 MPa in initial hydraulic test and 20.6 MPa in test renewal. Based on the practice of the four times successful hydraulic test of the main primary system for Qinshan II, the RCC-M and RSEM requirements related, brief test process and main results etc were introduced, and the differences between initial test and test renewal, as well as the risks, precautions and practical experience were summed up. They will be beneficial for the same kind PWR nuclear power plants. (authors)

2006-09-01

283

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.com

2004-10-03

284

Status and Trends of Thermal-Hydraulic System Codes for Nuclear Power Plants With Pressurized Water Reactors  

International Nuclear Information System (INIS)

Research and development of thermal-hydraulic system codes for nuclear power plants with pressurized water reactors were analyzed on their history, status and application ranges. The important roles of best-estimate methodology, codes coupling and codes qualification were pointed out. The development models of thermal-hydraulic system codes around the world provide references to China's self-innovation. (authors)

2009-11-01

285

Fiber optics in subsea control systems  

Energy Technology Data Exchange (ETDEWEB)

Present control systems for subsea production installations use either hydraulic lines for remote control of valves etc., or a combination of hydraulics and electrical lines. In the letter, signals to and from the subsea structures are transmitted on electrical lines, while hydraulics is used for transfer of power for opening and closing of valves. Fiber optics subsea offers the potential for a wider application of control and monitoring facilities with possibly improved reliability characteristics. A research program has been carried out since 1981 for several oil companies to develop an test out a fiber optics system for potential use on a subsea control system. The aim is to replace electrical metal cables with glass fibers carrying light signals. Fiber optics transmission systems are today well developed for land-based communications, and they are also being considered for use on offshore topside facilities. The application of fiber optics for subsea production control does however pose special problems, because the systems must be built to survive subsea for 25 years, and they must also have one or more subsea make/break connectors. 5 references.

Andersen, J.A.

1984-01-01

286

Remote controlled hydraulic-electric coupling tool for underwater use. Fjernstyrt hydraulisk-elektrisk koblingsverkty for undervannsbruk  

Energy Technology Data Exchange (ETDEWEB)

The invention relates to a remote controlled hydraulic-electric coupling tool for underwater use. The tool can be used by all bigger types of ROV (Remote Operational Vehicles) for connection to underwater installations for the supply and return of hydraulic and electric power, and for the different electric signals such as data communication, and video and radio signals. The tool consists of a male- and a female-member of which the male-member is connected to the ROV, and the female-member to the underwater installation. Both of the members are designed so that the operation of assemly leads to an accurate positioning for the final joining by means of an hydraulic locking mechanism. The mechanism can be unlocked in case the hydraulic control is failing. If the members are in a locked position, a coupling bar, with hydraulic and electric couplings, can be led into the manifold by means of hydraulic power for maintaining the coupled connection. 8 figs.

Baker, R.S.

1994-06-27

287

Discussion on sealing performance required in disposal system. Hydraulic analysis of tunnel intersections  

International Nuclear Information System (INIS)

The sealing performance of a repository must be considered in the safety assessment of the geological disposal system of the high-level radioactive waste. NUMO and JNC established 'Technical Commission on Sealing Technology of Repository' based on the cooperation agreement. The objectives of this commission are to present the concept on the sealing performance required in the disposal system and to develop the direction for future R and D programme for design requirements of closure components (backfilling material, clay plug, etc.) in the presented concept. In the first phase of this commission, the current status of domestic and international sealing technologies were reviewed; and repository components and repository environments were summarized subsequently, the hydraulic analysis of tunnel intersections, where a main tunnel and a disposal tunnel in a disposal panel meet, were performed, considering components in and around the engineered barrier system (EBS). Since all tunnels are connected in the underground facility, understanding the hydraulic behaviour of tunnel intersections is an important issue to estimate migration of radionuclides from the EBS and to evaluate the required sealing performance in the disposal system. In the analytical results, it was found that the direction of hydraulic gradient, hydraulic conductivities of concrete and backfilling materials and the position of clay plug had impact on flow condition around the EBS. (author)

2005-01-01

288

Evaluation of hydraulic efficiency of disinfection systems based on residence time distribution curves.  

Science.gov (United States)

Hydraulic efficiency is a vital component in evaluating the disinfection capability of a contact system. Current practice evaluates these systems based upon the theoretical detention time (TDT) and the rising limb of the residence time distribution (RTD) curve. This evaluation methodology is expected because most systems are built based on TDT under a "black-box" approach to disinfection system design. Within recent years, the proliferation of computational fluid dynamics (CFD) has allowed a more insightful approach to disinfection system design and analysis. Research presented in this study using CFD models and physical tracer studies shows that evaluation methods based upon TDT tend to overestimate, severely in some instances, the actual hydraulic efficiency as obtained from the system's flow and scalar transport dynamics and subsequent RTD curve. The main objective of this study was to analyze an alternative measure of hydraulic efficiency, the ratio t(10)/t(90), where t(10) and t(90) are the time taken for 10 and 90% of the input concentration to be observed at the outlet of a system, respectively, for various disinfection systems, primarily a pipe loop system, pressurized tank system, and baffled tank system, from their respective RTD curves and compare the results to the current evaluation method. PMID:21090605

Wilson, Jordan M; Venayagamoorthy, Subhas K

2010-12-15

289

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

290

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 relationshi...

2013-01-01

291

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

292

Comparative hydraulics of two fishery research circular tanks and recommendations for control of experimental bias  

Science.gov (United States)

Hydraulic characteristics inside two research circular tanks (1.5-m and 1.2-m diameter) with the same volume of water were studied to understand how they might affect experimental bias by influencing the behavior and development of juvenile fish. Water velocities inside each tank were documented extensively and flow behavior studied. Surface inflow to the 1.5-m tank created a highly turbulent and aerated surface, and produced unevenly distributed velocities within the tank. A low-flow velocity, or "dead" zone, persisted just upstream of the surface inflow. A single submerged nozzle in the 1.2-m tank created uniform flow and did not cause undue turbulence or introduce air. Flow behavior in the 1.5-m tank is believed to have negatively affected the feeding behavior and physiological development of a group of juvenile fall chinook salmon, Oncorhynchus tshawytscha. A new inflow nozzle design provided comparable flow behavior regardless of tank size and water depth. Maintaining similar hydraulic conditions inside tanks used for various biological purposes, including fish research, would minimize experimental bias caused by differences in flow behavior. Other sources of experimental bias are discussed and recommendations given for reporting and control of experimental conditions in fishery research tank experiments.

Odeh, M.; Schrock, R. M.; Gannam, A.

2003-01-01

293

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, Søren; Pedersen, Henrik C.

2011-01-01

294

Thermal-hydraulic analyses of the loss of cooling system accidents during shutdown operations  

Energy Technology Data Exchange (ETDEWEB)

In this study, the thermal-hydraulic behavior following the loss cooling system accident during shutdown operations at the Yong-Gwang nuclear power plant units 5, 6 is analyzed using RELAP5/MOD3.2 code, which is necessary to develop event tree and to quantify event sequence in the development of probabilistic safety assessment methodology and integrated accident management technology during low power/shutdown operations. The related thermal-hydraulic parameters such as core damage are defined, and quantitative occurring time after the accident for these thermal-hydraulic parameters is provided. Because the analyzed plant operating states represent various core decay heat level, primary system coolant level, and available vent paths, the effects of these various parameters on plant behavior following the accident are analyzed. As one of the operator's action to mitigate the accident, the effect of gravity feed on mitigation of the accident is analyzed by performing thermal-hydraulic analysis. The results of this study can contribute to the plant safety improvement because those can provide the time for an operator to take an action to mitigate the accident by providing quantitative time of core boiling, core uncovery, and core damage. The results of this study will provide information in developing operation procedure and accident management technology. (author). 25 refs.,71 figs., 13 tabs.

Son, Young Seok; Kim, Jin Hwan; Kim, Sung Kwon; Yeo, Hong Tae [Dong Eui University, Pusan (Korea)

1999-03-01

295

Sensitivity analysis of a passive thermal-hydraulic system  

International Nuclear Information System (INIS)

Full text of publication follows. Passive safety features are now of interest to the design of future generation reactors. Though passive safety systems are considered to be more reliable, the large uncertainty associated with the system response can not be ignored. It is necessary to identify the uncertain inputs that have the important impact on the uncertainty of the system performance. In this study, two global sensitivity measures, the first-order sensitivity index and the total-order sensitivity index, are applied to a passive decay heat removal system of a gas-cooled fast reactor for identifying the key uncertainty inputs. It is found that the uncertainty in the system pressure contributes the most to the uncertainty in the system outputs. In addition, the cooler wall temperature, the Nusselt number in the mixed convection regime and the friction factor in the mixed convection flow regime also have small impact on the uncertainty of the system outputs. (authors)

2011-05-02

296

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 particular importance to the analysis of transients such as ATWS. A comparison between the 3-D and 1-D neutronics representation is provided, along with a test case utilizing the composite RAMONA-3B/MINET code

1985-10-15

297

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

298

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

1985-01-01

299

Development and Simulation of Mathematical Modelling of Hydraulic Turbine  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Power system performance is affected by dynamic characteristics of hydraulic governor-turbines during and following any disturbance, such as occurrence of a fault, loss of a transmission line or a rapid change of load. Accurate modelling of hydraulic System is essential to characterize and diagnose the system response. In this article the mathematical modeling of hydraulic turbine is presented. The model is capable to implement the digital systems for monitoring and control replacing the conv...

Singh, Gagan; Chauhan, D. S.

2011-01-01

300

CSNI validation matrix for PWR and BWR thermal-hydraulic system codes  

International Nuclear Information System (INIS)

An internationally agreed validation matrix for PWR and BWR thermal-hydraulic system codes has been established by the CSNI-PWG-2 Task Group on Status and Assessment of Codes for Transients and ECCS. The matrix will be a guide for independent code assessment, will be a basis for the comparisons of code predictions performed with different system codes, and may contribute to the quantification of the uncertainty range of code predictions. (orig.)

1988-01-01

 
 
 
 
301

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.

2013-01-01

302

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

303

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

304

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

2011-12-01

305

High Resolution Hydraulic Profiling and Groundwater Sampling using FLUTeâ?¢ 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.

306

Three-dimensional transient hydraulic tomography in a highly heterogeneous glaciofluvial aquifer-aquitard system  

Science.gov (United States)

Hydraulic tomography has been proposed as an alternative site characterization method, however, relatively few field scale studies have been attempted. In this paper, we characterize the highly heterogeneous glaciofluvial aquifer-aquitard system at the North Campus Research Site, located at the University of Waterloo, Waterloo, Ontario, Canada using transient hydraulic tomography (THT). In particular, we performed 9 pumping tests in a network of wells to image the hydraulic conductivity (K) and specific storage (Ss) distributions (or tomograms) as well as their uncertainties in three-dimensions using the THT code of J. Zhu and T.-C. J. Yeh (2005). We first performed stochastic inverse modeling of the 9 pumping tests individually to gain insight into the level of detail that can be imaged. Then, we sequentially included 4 of the pumping tests in a THT analysis. The resulting K and Ss tomograms were then validated visually by comparing them to stratigraphy and permeameter K estimates. The K and Ss tomograms were also rigorously assessed through the simulation of all 9 pumping tests and comparing the simulated and observed drawdowns. We find that performing the inversion with multiple pumping tests (i.e., hydraulic tomography) yields improved results when compared to the analysis of individual pumping tests.

Berg, Steven J.; Illman, Walter A.

2011-10-01

307

Development of a thermal–hydraulic analysis software for a passive residual heat removal system  

International Nuclear Information System (INIS)

Highlights: ? A series of thermal–hydraulic models for the PRHRS in IPWR were established. ? An analysis software named TCIPsoft 1.0 has been developed. ? The effects of parameters on the PRHRS were studied in detail. -- Abstract: A series of reasonable mathematical and physical models for the thermal–hydraulic characteristic analysis of a passive residual heat removal system (PRHRS) in an integral pressurized water reactor were established. These models mainly include the core, once-through steam generator, nitrogen pressurizer, main coolant pump, and flow and heat transfer models. The flow and heat transfer models are suitable for the core with plate-type fuel element and the once-through steam generator with annular channel, respectively. A transient analysis code with Visual Fortran 6.5 has been developed to analyze the thermal–hydraulic characteristics of the PRHRS. Visual input, real-time processing and dynamic visualization output were achieved with Microsoft Visual Studio.NET 2008, which greatly facilitate applications in the engineering. The software was applied to analyze the effects of the heat transfer area of the PRHRS, the height difference between the residual heat exchanger center and the steam generator center, and the main steam valve turn-off time on the transient thermal–hydraulic characteristics of PRHRS. The obtained analysis results are significant to the improvement design of the PRHRS and the safety operation of the integral pressurized water reactor.

2012-10-01

308

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)

1986-01-01

309

Conceptual Design of a Hydraulic Valve Train System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 beha...

2001-01-01

310

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

311

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

312

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

313

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

314

Neutronic and thermal hydraulic of dry cask storage systems  

International Nuclear Information System (INIS)

Interim spent fuel storage systems must provide for the safe receipt, handling, retrieval and storage of spent nuclear fuel before reprocessing or disposal. In the context of achieving these objectives, the following features of the design are to be taken into consideration: to maintain fuel subcritical, to remove spent fuel residualheat, and to provide for radiation protection. These features in the design of a dry cask storage system were analyzed for normal operating conditions by employing COBRA-SFS, SCALE4.4 (ORIGEN, XSDOSE, CSAS6) codes. For a metal-shielded type storage system, appropriate designs, in accordance with safety assurance limits of IAEA, were obtained for spent fuel burned to 33000, 45000 and 55000 MW d/t and cooled for 5 and 10 years

2000-01-01

315

Hydraulics in mining - proceedings  

Energy Technology Data Exchange (ETDEWEB)

Six papers are presented on aspects of hydraulics in mining. The development of hydraulic fluids with properties to minimise corrosion and demulsification, and with resistance to fire is described; and modern fluids compared with mineral oils. Pressure compensated axial piston pumps for hydraulic roof support systems are discussed, as well as new types of servovalves and seals. Papers have been abstracted separately.

1985-01-01

316

Thermal-Hydraulic Analysis of Spent Fuel Storage Systems.  

Science.gov (United States)

This paper describes the COBRA-SFS (Spent Fuel Storage) computer code, which is designed to predict flow and temperature distributions in spent nuclear fuel storage and transportation systems. The decay heat generated by spent fuel in a dry storage cask i...

D. R. Rector C. L. Wheeler N. J. Lombardo

1987-01-01

317

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

318

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

319

Development of CFD Analysis Methodology of Hydraulic Load Evaluation in POSRV Piping System  

International Nuclear Information System (INIS)

APR1400 has been improved as an advanced light water reactor that adopts new technology's. One of major technologies is IRWST(In-containment Refueling Water Storage Tank) placed inside containment. In order to adjust the new technology when POSRV(Pilot Operated Safety Relief Valve) is opened, POSRV-IRWST linked line must be kept safe. Theoretical solution and experimental data are needed for structure integrity, but proven data are insufficient from the viewpoint of hydrodynamics. The hydrodynamic flow analysis and the thermodynamic behavior analysis should be performed by using CFD. The objective of this study is to develop the CFD analysis methodology of hydraulic load evaluation in IRWST piping system. This method is a basic hydraulic load evaluation in POSRV piping system. Also, this will help to analyze fluid-structural interface and to predict special phenomena. Therefore, that can be used as a basis to the most suitable design

2009-10-01

320

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

 
 
 
 
321

An investigation of the use of soybean oil in hydraulic systems  

Energy Technology Data Exchange (ETDEWEB)

This report is the result of grants from the soybean growers in Iowa for investigating the potential use of soybean oil in hydraulic systems and other industrial lubricant applications. It was observed that soybean oil naturally performs well in lubricating pump components. The lack of oxidative stability, however, causes an increase in the viscosity of untreated soybean oil during use in hydraulic systems. Three approaches were identified to address this problem. One was the use of additives, second was the use of genetically altered seeds with altered fatty acid profiles, and third was through chemical modification of the soybean oil. The results indicated that the performance of soybean oil can be improved through one or more of the approaches identified. (author)

Honary, L.A.T. [University of Northern Iowa, Cedar Falls, IA (United States). Ag-Based Industrial Lubricants (ABIL) Research Program

1996-04-01

322

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 var...

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

2007-01-01

323

Study of transient hydraulic in the essential service water system in NPP. Cofrentes  

International Nuclear Information System (INIS)

The present paper presents the study of the possible transient hydraulic that they could occur in the essential service water system due to changes in modes of operation, as well as replacement of components or failure of these within the same operating mode. For a complete analysis, it has created a computer model of the system through software EcosimPro, whereby different models have been corresponding to each division's system, making the check that in any mode of operation, and in any event, the values be exceeded the design for the system and its components.

2013-01-01

324

How to effectively compute the reliability of a thermal-hydraulic nuclear passive system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The computation of the reliability of a thermal-hydraulic (T-H) passive system of a nuclear power plant can be obtained by (i) Monte Carlo (MC) sampling the uncertainties of the system model and parameters, (ii) computing, for each sample, the system response by a mechanistic T-H code and (iii) comparing the system response with pre-established safety thresholds, which define the success or failure of the safety function. The computational effort involved can be prohibitive because of the lar...

Zio, Enrico; Pedroni, Nicola

2011-01-01

325

Control system design method  

Energy Technology Data Exchange (ETDEWEB)

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

326

Validation of Divertor Cassette locking system with a hydraulic jack tool  

International Nuclear Information System (INIS)

The divertor area of ITER vacuum vessel consists of 54 modular cassettes which must be exchanged after every 3-4 years of plasma operations. Divertor Cassettes are locked in the vacuum vessel by means of compressing them against the rails mounted in the inner and outer walls of the vacuum vessel. According to ITER reference cassette locking system, a Divertor Cassette has to be preloaded with a compression force of 360 kN against the vacuum vessel rails. The preloading of the cassettes is carried out with a hydraulic jack tool which is fitted into the cassette body. The Jack will transmit a hydraulic force by pushing the cassette latches against the outer rails, transmitting therefore the required preloading compression force to the cassette. This paper deals with the validation of Divertor Cassette locking system and it also describes the design and testing of a radiation-hard, water hydraulic jack. The validation of Divertor Cassette locking system has been the first Divertor Maintenance operation tested at Divertor Test Platform 2.

2009-06-01

327

Thermal-hydraulic analysis of spent fuel storage systems  

International Nuclear Information System (INIS)

This paper describes the COBRA-SFS (Spent Fuel Storage) computer code, which is designed to accurately predict flow and temperature distributions in spent nuclear fuel storage and transportation systems. The decay heat generated by spent fuel in a dry storage cask is removed through a combination of conduction, natural convection, and thermal radiation. One major advantage of COBRA-SFS is that fluid recirculation within the cask is computed directly by solving the mass and momentum conservation equations. In addition, thermal radiation heat transfer is modeled using detailed radiation exchange factors based on quarter-rod segments. The equations governing mass, momentum, and energy conservation for incompressible flows are presented, and the semi-implicit solution method is described. COBRA-SFS predictions are compared to temperature data from a spent fuel storage cask test, and the effect of different fill media on the cladding temperature distribution is discussed. The effect of spent fuel consolidation on cask thermal performance is also investigated

1987-01-01

328

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

1981-01-01

329

New energy conservation control strategy for hydraulic drives; Neue Regelstrategie zur Energieeinsparung bei hydraulischen Antrieben  

Energy Technology Data Exchange (ETDEWEB)

Machines with cyclical load processes which require much power and have large alternations of load often operate with low efficiency. This is due to the fact that the necessary adaptation of the machine to each load process which would have to be done manually is often for cost reasons or due to a lack of time or knowledge not carried out. Within the scope of a thesis a hydraulic system with automatic adaptation to load changes has been developed. It has also in case of different cyclical loads a high efficiency. It is a learning system which improves the efficiency further. The article describes the structure and mode of operation of the system. (HW) [Deutsch] Maschinen, bei denen zyklische Lastprozesse eine grosse Leistung mit entsprechenden Lastwechseln erfordern, arbeiten haeufig mit niedrigen Wirkungsgraden, die dadurch verursacht werden, dass die Maschine eigentlich fuer jeden Lastprozess energetisch neu abgestimmt werden muss (manuell), was aus Zeit-, Geld- oder Kenntnisgruenden nicht immer stattfindet. Im Rahmen einer Dissertation wurde deshalb ein hydraulisches System entwickelt, das bei unterschiedlichen zyklischen Lasten einen hohen Wirkungsgrad aufweist und sich ausserdem automatisch an Lastaenderungen anpasst. Das System hat lernende Eigenschaften, was zu immer besseren Wirkungsgraden fuehrt. Der vorliegende Beitrag stellt Aufbau und Funktionsweise dar. (HW)

Burgt, J.A.H. van der [Kloeckner Haensel Tevopharm B.V. (Netherlands); Hezemans, P.M.A.L. [Inst. fuer Antriebstechnik und Tribotechnik, Fachbereich Systemtechnik fuer Antriebssysteme, Technische Univ. Eindhoven (Netherlands)

1994-11-14

330

GCFR plant control system  

International Nuclear Information System (INIS)

A plant control system is being designed for a gas-cooled fast breeder reactor (GCFR) demonstration plant. Control analysis is being performed as an integral part of the plant design process to ensure that control requirements are satisfied as the plant design evolves. The load control portion of the plant control system provides stable automatic (closed-loop) control of the plant over the 25% to 100% load range. Simulation results are presented to demonstrate load control system performance. The results show that the plant is controllable at full load with the control system structure selected, but gain scheduling is required to achieve desired performance over the load range

1980-06-06

331

GCFR plant control system  

Energy Technology Data Exchange (ETDEWEB)

A plant control system is being designed for a gas-cooled fast breeder reactor (GCFR) demonstration plant. Control analysis is being performed as an integral part of the plant design process to ensure that control requirements are satisfied as the plant design evolves. The load control portion of the plant control system provides stable automatic (closed-loop) control of the plant over the 25% to 100% load range. Simulation results are presented to demonstrate load control system performance. The results show that the plant is controllable at full load with the control system structure selected, but gain scheduling is required to achieve desired performance over the load range.

Estrine, E.A.; Greiner, H.G.

1980-05-01

332

Thermal-hydraulic analysis of spent fuel storage systems  

International Nuclear Information System (INIS)

This paper describes the COBRA-SFS (Spent Fuel Storage) computer code, which is designed to predict flow and temperature distributions in spent nuclear fuel storage and transportation systems. The decay heat generated by spent fuel in a dry storage cask is removed through a combination of conduction, natural convection, and thermal radiation. One major advantage of COBRA-SFS is that fluid recirculation within the cask is computed directly by solving the mass and momentum conservation equations. In addition, thermal radiation heat transfer is modeled using detailed radiation exchange factors based on quarter-rod segments. The equations governing mass, momentum, and energy conservation for incompressible flows are presented, and the semi-implicit solution method is described. COBRA-SFS predictions are compared to temperature data from a spent fuel storage cask test and the effect of different fill media on the cladding temperature distribution is discussed. The effect of spent fuel consolidation on cask thermal performance is also investigated. 16 refs., 6 figs., 2 tabs

1987-08-09

333

Thermal-hydraulic analysis of spent fuel storage systems  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the COBRA-SFS (Spent Fuel Storage) computer code, which is designed to predict flow and temperature distributions in spent nuclear fuel storage and transportation systems. The decay heat generated by spent fuel in a dry storage cask is removed through a combination of conduction, natural convection, and thermal radiation. One major advantage of COBRA-SFS is that fluid recirculation within the cask is computed directly by solving the mass and momentum conservation equations. In addition, thermal radiation heat transfer is modeled using detailed radiation exchange factors based on quarter-rod segments. The equations governing mass, momentum, and energy conservation for incompressible flows are presented, and the semi-implicit solution method is described. COBRA-SFS predictions are compared to temperature data from a spent fuel storage cask test and the effect of different fill media on the cladding temperature distribution is discussed. The effect of spent fuel consolidation on cask thermal performance is also investigated. 16 refs., 6 figs., 2 tabs.

Rector, D.R.; Wheeler, C.L.; Lombardo, N.J.

1987-01-01

334

Application of gamma-rays in hydraulic conveyance pipeline systems  

International Nuclear Information System (INIS)

Transmission measurements of gamma radiation in two selective energy channels and at two positions of the pipe may successfully be used for non-contact determinations of the most important conveyor-flow parameters such as medium density, local space concentrations, particle drift speeds and, by combination of these data, mass transport per unit time. The two-channel technique improves the accuracy of density analysis and allows, in contrast to conventional procedures, simultaneous measurements of individual volume fractions in three-component flows. If the chemical composition of one component is not constant, the range of this variation has to be investigated and to be taken into account as a systematic error. For measuring the mean drift velocity of particles, two gamma-ray gates are attached to the pipe string, one behind the other in the direction of the flow. From the dc-current modulations at both detector outputs phase shift and mean velocity can be deduced by using cross-correlation analysis. At the same time this measuring technique delivers the mean particle size and the possibility to recognise in good time imminent component plugs blocking the mass flow. In addition to these transport data relevant to the layout and operation of mining systems, the knowledge of the wear performance of the pipe string is of great importance. Activation of tube parts allows very sensitive wear measurements by detecting changes of the activity. (author)

1979-01-01

335

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

2013-10-01

336

Hydraulic transportation of imported coal. A schematic system assessment  

Energy Technology Data Exchange (ETDEWEB)

Sweden has no domestic resources of coal and an import of up to about 10 Mtonnes per year for energy production has been discussed. A large scale use of steam coal in Sweden will probably be limited by strict environmental regulations. Only coals of very high quality can be considered. If high quality coals are not available at a reasonable price, it may be economically feasible to clean the coal prior to combustion, in combination with stack gas scrubbing to attain given emission standards. In advanced physical cleaning methods the coal is crushed to a maximum particle size of about 1 mm by wet milling. This means that the coal is in the form of a slurry which can easily be transported in pipes. The possibility of Swedish participation in mining operations in an exporting country cannot be excluded. A system based on complete transportation and handling of the coal in the form of a slurry, from a mine abroad and then overseas on a ship to a power plant in Sweden, is not expected to be industrially available within the decade to come. However, in a schematic example, mainly based on technology available at present, a coal imported in a dry state is unloaded, stored and transported as a slurry and the delivered to a power plant. It is suggested that the coal should be cleaned and the refuse should be handled on a nearly dry basis, in order to minimize environmental impacts. The coal lost in the cleaning process can be partly recovered and delivered for secondary energy use. The energy requirements of some operations in the transportation, handling and processing of coal are briefly discussed. Finally, a rough estimation is made of transportation of coal in a long-distance slurry pipeline from a mine on the continent or from a interscandincavian port.

Sellgren, A.

1980-02-01

337

Design of Instrumentation and Control System for ATLAS  

International Nuclear Information System (INIS)

The ATLAS(Advanced Thermal-hydraulic Test Loop for Accident Simulation) facility, which is a 1/2-height, 1/288-volume scaled and full-pressure test facility, has recently been constructed under the thermal-hydraulic integral effect test program by KAERI(Korea Atomic Energy Research Institute). The ATLAS consists of a reactor vessel and a core simulator, two steam generators, a pressurizer, four main coolant pumps, the related reactor coolant system (RCS) piping, safety injection systems, and secondary system and auxiliary systems. This paper introduces the instrumentation and control system of the ATLAS facility. The operation procedure, control logics and transient test scenarios have been developed to use the analysis result analyzed by a multi-dimensional best estimate thermal hydraulic code MARS 3.0

2007-05-10

338

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

339

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

340

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

 
 
 
 
341

Technique of analysis and error detection for thermo-hydraulic system data  

International Nuclear Information System (INIS)

Statistical techniques based on estimation theory were developed for the analysis of steady-state data from thermo-hydraulic systems, which could be either experimental loops or operating power plants. The method seeks to resolve errors in the component heat balances which describe the system, to obtain system parameter estimates which are more accurate than the raw data, and to flag possible faulty sensors. Sample results are given for the analysis of test data from the Sodium Loop Safety Faciltiy (SLSF) P3 experiment

1985-07-01

342

Hydraulic actuator mechanism to control aircraft spoiler movements through dual input commands  

Science.gov (United States)

An aircraft flight spoiler control mechanism is described. The invention enables the conventional, primary spoiler control system to retain its operational characteristics while accommodating a secondary input controlled by a conventional computer system to supplement the settings made by the primary input. This is achieved by interposing springs between the primary input and the spoiler control unit. The springs are selected to have a stiffness intermediate to the greater force applied by the primary control linkage and the lesser resistance offered by the spoiler control unit. Thus, operation of the primary input causes the control unit to yield before the springs, yet, operation of the secondary input, acting directly on the control unit, causes the springs to yield and absorb adjustments before they are transmitted into the primary control system.

Irick, S. C. (inventor)

1981-01-01

343

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)

1980-01-01

344

Coordinated joint motion control system with position error correction  

Science.gov (United States)

Disclosed are an articulated hydraulic machine supporting, control system and control method for same. The articulated hydraulic machine has an end effector for performing useful work. The control system is capable of controlling the end effector for automated movement along a preselected trajectory. The control system has a position error correction system to correct discrepancies between an actual end effector trajectory and a desired end effector trajectory. The correction system can employ one or more absolute position signals provided by one or more acceleration sensors supported by one or more movable machine elements. Good trajectory positioning and repeatability can be obtained. A two-joystick controller system is enabled, which can in some cases facilitate the operator's task and enhance their work quality and productivity.

Danko, George (Reno, NV)

2011-11-22

345

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

1995-09-01

346

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

347

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

1987-08-31

348

Hydraulic fracture design optimization  

Energy Technology Data Exchange (ETDEWEB)

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

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

1992-06-01

349

Hydraulic fracture design optimization  

Energy Technology Data Exchange (ETDEWEB)

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

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

1992-01-01

350

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

351

System of controlling a blowout preventer with cut slips of underwater antiblowout equipment  

Energy Technology Data Exchange (ETDEWEB)

A system is suggested for controlling a blowout preventer with cut slips of underwater antiblowout equipment. It includes electric and pneumatic drive pumps, whose pressure lines are connected through hydraulically controllable cut-off valves with above water and underwater hydraulic pneumatic storage batteries and through hydraulically controllable hydrodistributors of opening and closing the blowout preventer with cavities of the hydraulic cylinders of the blowout preventer, and hydraulically controllable valve for actuating the pneumatic pump. In order to reduce the overall dimensions and weight of the blowout preventer, the control system is supplied with two additional reverse valves and additional three-course valve whose feedline is connected to the cut-off valve of the underwater storage batteries, and two outlets to the pressure line of the pumps. One of them is connected through the additional reverse valve. The cut-off valve of the above-water hydraulic pneumatic storage batteries has three courses, and its outlet is connected to the pressure line of the pumps through an additional reverse valve, control line of the cut-off valve of the above-water hydraulic pneumatic storage batteries, additional hydrodistributor and valve for triggering the pneumatic pump are hydraulically connected to the control line of the hydrodistributor for closing the blowout preventer.

Pyndak, V.I.; Abrosimov, A.S.; Alavushev, V.Y.; Grishkov, I.M.; Khokhlov, Y.I.; Nikonov, G.R.; Ponomarenko, I.A.; Stakhov, B.G.

1981-02-15

352

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

1991-10-03

353

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

Energy Technology Data Exchange (ETDEWEB)

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.

Joo, Han Gyu; Cho, Byung Oh; Zee, Sung Quun

1998-12-01

354

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

1998-01-01

355

Development of 2-loop feedwater control system  

International Nuclear Information System (INIS)

A 2-loop feedwater control system has been developed for automatic transfer control of the reactor feed pumps (RFP's) in BWR plants. This system consists of a master level controller and sub-loop flow controllers for each of the RFP's. Control characteristics of the 2-loop control system were investigated using a dynamic analysis code for the condensate feedwater system. Although the RFP system has a hydraulic coupling effect, the flow control loops become stable by setting adequate controller gains in the sub-loop flow controllers. The control characteristics in the major loop were modified in their initial response to level setpoint change by using a lead/lag compensator. Moreover, reactor core cooling was protected sufficiently during the transient in a trip of a turbine driven RFP. From simulation results of the transfer controls from the motor driven RFP to turbine driven RFP, it was ascertained that the 2-loop control system has such advantages as shorter completion time and superior controllability against ON-OFF action of a RFP recirculation valve during transfer control. (author)

1981-01-01

356

On topographic controls of soil hydraulic parameter scaling at hillslope scales  

Science.gov (United States)

Most upscaling efforts for soil hydraulic parameters developed thus far have opted to ignore the effect of topography in their derivation of effective parameter values. This approach, which considers a flat terrain with no lateral flows, is reasonable as long as the coarser support dimensions are of the order of a few hundred meters. In such a scenario, the upscaled characteristics of the parameters are governed predominantly by the texture and structure of the soil in the domain. However, when upscaling fine-scale hydraulic parameter data to much larger extents (hillslope scales and beyond), topography plays a bigger role and can no longer be ignored. Efforts to model hydrologic processes and phenomena, with particular emphasis on those occurring in the unsaturated zone, are conducted at various scales. We present here a study to isolate the influence of topographic variations on the effective, upscaled soil hydraulic parameters under different hillslope configurations. The power-averaging operator algorithm was used to aggregate fine-scale soil hydraulic parameters to coarser resolutions. Hydrologic scenarios were simulated using HYDRUS-3D for four different topographic configurations under different conditions to test the validity of the upscaled soil hydraulic parameters. The outputs from the simulations (fluxes and soil moisture states) were compared across multiple scales for validating the effectiveness of the upscaled soil hydraulic parameters. It was found that the power-averaging algorithm produced reasonably good estimates of effective soil hydraulic parameters at coarse scales. Further, a probable threshold dimension beyond which the topography dominates the soil hydraulic property variation was analyzed. On the basis of only the topography, the scaling algorithm was able to capture much of the variation in soil hydraulic parameters required to generate equivalent flows and soil moisture states in a coarsened domain.

Jana, Raghavendra B.; Mohanty, Binayak P.

2012-02-01

357

Flight Control Actuation System.  

Science.gov (United States)

A flight control actuation system comprises a controller, electromechanical actuator and a pneumatic actuator. During normal operation, only the electromechanical actuator is needed to operate a flight control surface. When the electromechanical actuator ...

J. I. Kern L. T. Gaines P. S. Evans P. T. Wingett

2004-01-01

358

ISABELLE control system  

Energy Technology Data Exchange (ETDEWEB)

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.

Humphrey, J W; Frankel, R S; Niederer, J A

1980-01-01

359

Thermal hydraulic performance of seawater desalination system using a nuclear heating reactor  

International Nuclear Information System (INIS)

A physical-mathematical model was developed to explore the thermal hydraulic performance of a vertical tube multi-effect distillation seawater desalination system coupled with the nuclear heating reactor. Two temperature difference distribution schemes, equal temperature difference and equal heat transfer area temperature difference, were used for the system design. The results indicate that the gain-output-ratio with both temperature difference distribution schemes can be up to 20. However, the design with the equal heat transfer area temperature difference is more suitable for a tower design. The results would be helpful for designing a large capacity vertical tube multi-effect distillation desalination plant

2002-05-01

360

Influence of hydraulic regimes on bacterial community structure and composition in an experimental drinking water distribution system.  

Science.gov (United States)

Microbial biofilms formed on the inner-pipe surfaces of drinking water distribution systems (DWDS) can alter drinking water quality, particularly if they are mechanically detached from the pipe wall to the bulk water, such as due to changes in hydraulic conditions. Results are presented here from applying 454 pyrosequencing of the 16S ribosomal RNA (rRNA) gene to investigate the influence of different hydrological regimes on bacterial community structure and to study the potential mobilisation of material from the pipe walls to the network using a full scale, temperature-controlled experimental pipeline facility accurately representative of live DWDS. Analysis of pyrosequencing and water physico-chemical data showed that habitat type (water vs. biofilm) and hydraulic conditions influenced bacterial community structure and composition in our experimental DWDS. Bacterial community composition clearly differed between biofilms and bulk water samples. Gammaproteobacteria and Betaproteobacteria were the most abundant phyla in biofilms while Alphaproteobacteria was predominant in bulk water samples. This suggests that bacteria inhabiting biofilms, predominantly species belonging to genera Pseudomonas, Zooglea and Janthinobacterium, have an enhanced ability to express extracellular polymeric substances to adhere to surfaces and to favour co-aggregation between cells than those found in the bulk water. Highest species richness and diversity were detected in 28 days old biofilms with this being accentuated at highly varied flow conditions. Flushing altered the pipe-wall bacterial community structure but did not completely remove bacteria from the pipe walls, particularly under highly varied flow conditions, suggesting that under these conditions more compact biofilms were generated. This research brings new knowledge regarding the influence of different hydraulic regimes on the composition and structure of bacterial communities within DWDS and the implication that this might have on drinking water quality. PMID:23182667

Douterelo, I; Sharpe, R L; Boxall, J B

2013-02-01

 
 
 
 
361

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

362

The control system  

International Nuclear Information System (INIS)

The control system of the NAC cyclotrons utilizes a number of 16-bit minicomputers, 8-bit microcomputers, the CAMAC network known as the Executive or System Crate system, and several control consoles connected to the minicomputers by CAMAC parallel branches. During the past year our activities have been confined mostly to the interfacing of accelerator hardware to the control system and the writing of 'application' software for its control. The interfacing of the solid-pole cyclotron(SPC1) to the control system has been completed, as has the control of the magnet power supplies of the separated-sector cyclotron (SSC) and of several sub-systems of the transfer beamline between(SPC1) and SSC. For much of the year two control systems were maintained, one for the 'dedicated' control of the SSC magnet power supplies during the measurement of SSC magnetic fields, and the other for the control of SPC1. Several control 'runs' of SPC1 took place, during which it was possible to determine and eliminate some of the weaknesses of the console and application software. After the SSC field measurements had been completed, the two control systems were united into a single system. At present the control system is being used routinely for control of SPC1. Interfacing of the transfer beamline and the remaining sub-systems of the SSC is continuing

1985-01-01

363

Fish pass assessment by remote control: a novel framework for quantifying the hydraulics at fish pass entrances  

Science.gov (United States)

Fragmentation of aquatic habitats can lead to the extinction of migratory fish species with severe negative consequences at the ecosystem level and thus opposes the target of good ecological status of rivers defined in the EU Water Framework Directive (WFD). In the UK, the implementation of the EU WFD requires investments in fish pass facilities of estimated 532 million GBP (i.e. 639 million Euros) until 2027 to ensure fish passage at around 3,000 barriers considered critical. Hundreds of passes have been installed in the past. However, monitoring studies of fish passes around the world indicate that on average less than half of the fish attempting to pass such facilities are actually successful. There is a need for frameworks that allow the rapid identification of facilities that are biologically effective and those that require enhancement. Although there are many environmental characteristics that can affect fish passage success, past research suggests that variations in hydrodynamic conditions, reflected in water velocities, velocity gradients and turbulences, are the major cues that fish use to seek migration pathways in rivers. This paper presents the first steps taken in the development of a framework for the rapid field-based quantification of the hydraulic conditions downstream of fish passes and the assessment of the attractivity of fish passes for salmonids and coarse fish in UK rivers. For this purpose, a small-sized remote control platform carrying an acoustic Doppler current profiler (ADCP), a GPS unit, a stereo camera and an inertial measurement unit has been developed. The large amount of data on water velocities and depths measured by the ADCP within relatively short time is used to quantify the spatial and temporal distribution of water velocities. By matching these hydraulic features with known preferences of migratory fish, it is attempted to identify likely migration routes and aggregation areas at barriers as well as hydraulic features that may distract fish away from fish pass entrances. The initial steps of the framework development have focused on the challenge of precise spatial data referencing in areas with limited sky view to navigation satellites. Platform tracking with a motorised Total Station, various satellite-based positioning solutions and simultaneous localisation and mapping (SLAM) based on stereo images have been tested. The effect of errors in spatial data referencing on ADCP-derived maps of flow features and bathymetry will be quantified through simultaneous deployment of these navigation technologies and the ADCP. This will inform the selection of a cost-effective platform positioning system in practice. Further steps will cover the quantification of uncertainties in ADCP data caused by highly turbulent flows and the identification of suitable ADCP data sampling strategies at fish passes. The final framework for fish pass assessment can contribute to an improved understanding of the interaction of fish and the complex hydraulic river environment.

Kriechbaumer, Thomas; Blackburn, Kim; Gill, Andrew; Breckon, Toby; Everard, Nick; Wright, Ros; Rivas Casado, Monica

2014-05-01

364

Stomatal control and hydraulic conductivity in "Manzanilla" olive trees under different water regimes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We studied the response of leaf water potential, stomatal conductance (gs), leaf specific hydraulic conductivity (Kl) and percentage loss of hydraulic conductivity (PLC) in current-year shoots of 40-year-old ‘Manzanilla’ olive trees under three water treatments: Rainfed, in which rainfall was the only source of water; FAO, in which the trees were under localized irrigation to replace crop water demand; Pond, in which the whole root zone of the trees was maintained under non...

Torres Ruiz, Jose? Manuel; Ferna?ndez Luque, Jose? Enrique; Di?az-espejo, Antonio; Marti?n Palomo, Mª Jose?; Morales Sillero, Ana; Muriel Ferna?ndez, Jose? L.; Romero Vicente, Rafael

2011-01-01

365

RBMK coupled neutronics/thermal-hydraulics analyses by two independent code systems  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the coupled neutronics/thermal-hydraulics activities carried out in the framework of the part B of the TACIS project R2.03/97, 'Software development for accident analysis of RBMK reactors in Russia'. Two independent code systems were assembled, one from the Russian side and the other from the Western side, for studying RBMK core transients. The Russian code system relies on the use of code UNK for neutron data libraries generation and the three-dimensional neutron kinetics thermal-hydraulics coupled codes BARS-KORSAR for plant transient analyses. The Western code system is instead based on the lattice physics code HELIOS and on the RELAP5-3D C code. Several activities were performed for testing code system's capabilities: the neutron data libraries were calculated and verified by precise Monte Carlo calculations, the coupled codes' steady state results were compared with plant detectors' data, and calculations of several transients were compared. Finally, both code systems proved to have all the capabilities for addressing reliable safety analyses of RBMK reactors. (authors)

Parisi, C.; D' Auria, F. [Univ. of Pisa, Dept. of Mechanical, Nuclear and Production Engineering, via Diotisalvi, 2, 56100 Pisa (Italy); Malofeev, V. [Kurchatov Inst., Kurchatov Square 1, Moscow 123182 (Russian Federation); Ivanov, B.; Ivanov, K. [Pennsylvania State Univ., RDFMG, 230 Reber Building, Univ. Park, PA 16802 (United States)

2006-07-01

366

Thermal-hydraulic tests for primary coolant circuit structures of top entry system for LMFBR  

International Nuclear Information System (INIS)

The Top Entry System for the LMFBR is a system which constitutes the primary reactor cooling loops by installing inverted U-piges among the reactor vessel (RV), intermediate heat exchangers (IHX) and the primary pumps. The adoption of this system has allowed to considerably reduce the overall lenngth of pipings compared with the conventional loop type FBR and furthermore, has the advantage of drastically minimizing the area of the container vessel. However, as it is new concept to provide a siphon type piping at the upper part of each component, various R and D works are being carried out relating to the Top Entry System in order to support the designing of the 1000 MWe LMFBR plant. As one of the R and Ds carried out, thermal-hydraulic tests were conducted. A water loop test on the model system to examine local thermal head relating to natural circulation and thermal transient of each part, and a sodium loop test to examine generative conditions of thermal stratification at the inverted U-pipe were conducted. As it is necessary to use an analysis code in order to predict thermal-hydraulics inside the inverted U-pipe, and examination by a two dimensional FEM code was performed using the above test data. (orig.)

1987-01-01

367

Hydraulic Geometry, GIS and Remote Sensing, Techniques against Rainfall-Runoff Models for Estimating Flood Magnitude in Ephemeral Fluvial Systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper shows the combined use of remotely sensed data and hydraulic geometry methods as an alternative to rainfall-runoff models. Hydraulic geometric data and boolean images of water sheets obtained from satellite images after storm events were integrated in a Geographical Information System. Channel cross-sections were extracted from a high resolution Digital Terrain Model (DTM) and superimposed on the image cover to estimate the peak flow using HEC-RAS. The proposed methodology has been...

Carmelo Conesa-Garcia; Vicente Caselles-Miralles; Sanchez Tomas, Juan M.; Rafael Garcia-Lorenzo

2010-01-01

368

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

369

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

370

Using radar tomography, tracer experiments and hydraulic data to characterize fractured rock flow systems  

Science.gov (United States)

Among the most pressing problems in hydrogeology is describing heterogeneity in fractured rock, where data are typically local and sparse, and permeability varies by orders of magnitude over short distances. This dissertation presents new approaches to characterize fractured rock groundwater flow systems using cross-well radar, tracer, and hydraulic experiments. The methods are demonstrated using data from the U.S. Geological Survey Fractured Rock Hydrology Research Site near Mirror Lake, New Hampshire. One underutilized source of information in characterization of fractured rock is hydraulic connection data. Wells connected by a high-permeability fracture zone tend to exhibit similar hydraulic responses during pumping or drilling. A simulated-annealing algorithm is presented to condition geostatistical simulations to inferred connections. The method is used to generate 3-D realizations of fracture-zone geometry at the Mirror Lake Site. Results indicate the likely extents of specific zones. Flow models based on realizations are calibrated to hydraulic data to estimate the hydraulic parameters of the fracture zones and surrounding bedrock. Another innovative source of information for characterization is time-lapse difference-attenuation radar tomography, which has been used to monitor the migration of electrically conductive saline tracers. A sequential-inversion methodology is presented and demonstrated for a synthetic example. The method uses space-time parameterization and regularization to account for changes in concentration that occur quickly relative to the collection of radar data. The time-lapse tomographic inversion method is applied to data from the Mirror Lake Site. Difference-attenuation tomography indicates the timing and spatial distribution of tracer transport in three planes that form a triangular prism. Tracer migration is focused along a preferential pathway. Comparison of the time-series of tomograms with the outlet tracer data suggests that much of the tracer plume left the triangular prism of the image planes. An integrated interpretation of the difference-attenuation and concentration data is presented. Alternative conceptual models consistent with the tomograms are considered. Tomographic information determined the zonation of flow and transport parameters. Inverse modeling identified several models consistent with the timing of the tracer peak in the image planes. The combination of time-lapse tomography and tracer experiments provides a more detailed description of heterogeneity than heretofore possible.

Day-Lewis, Frederick David

371

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

372

PDX diagnostic control system  

International Nuclear Information System (INIS)

This paper describes a computer-base diagnostic control system operating on the PDX Tokamak. The prime function of the system is to control mechanical positioning devices associated with various diagnostics including Thomson Scattering, X-Ray Pulse Height Analyzer, Rotating Scanning Monochromator, Fast Ion Detection Experiment, Bolometers and Plasma Limiters. The diagnostic control system consists of a PDP-11/34 computer, a CAMAC system partitioned between the PDX control room and the PDX machine area, and special electronic control modules developed at PPL. The special modules include a digital closed loop motor controller and user interface control panel for control and status display. A standard control panel was developed for interfacing each system user with the PDP-11/34 computer, through specially developed CAMAC modules

1981-10-29

373

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

374

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 guidanc...

Wang Qi; Luo Yanjie; Wang Jingyue

2012-01-01

375

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

International Nuclear Information System (INIS)

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

2012-11-26

376

Control system model for the SASSYS-1 systems analysis code  

International Nuclear Information System (INIS)

A general control system model has been coupled with SASSYS-1 one-dimensional liquid-metal reactor (LMR) thermal-hydraulics code to provide an integrated treatment for LMRs similar to the general control system/thermal-hydraulics treatment available for light water reactors in RETRAN. With the development of innovative reactor design concepts, the emphasis on LMR safety has shifted away from the consideration of hypothetical whole-core disruptive accidents (HCDAs) to transients with much milder consequences and of much longer time scale. This increase in time scale, rendered possible by the incorporation of a number of inherently safe design features, makes it important to consider the possibility of control system action in the long-term response of the plant and to ascertain that inadvertent aggravation of the transient by control action is not possible. As a step in this direction, the Argonne National Laboratory (ANL) LMR system transient code SASSYS-1, which evolved from the ANL LMR HCDA code, SAS4A, was modified to include a control system simulation module

1986-06-15

377

7 CFR 2902.28 - Stationary equipment hydraulic fluids.  

Science.gov (United States)

...Stationary equipment hydraulic fluids. 2902...Stationary equipment hydraulic fluids. (a...use in stationary hydraulic equipment systems...various mechanical parts, such as cylinders, pumps, valves, pistons, and...

2010-01-01

378

Hydraulic mode simulation of NPP power unit pipeline systems by means of a training facility  

International Nuclear Information System (INIS)

The problem of hydraulic mode simulation of pipeline systems at the training facility is presented. Methods for solution of Kirchgoff equations for circuits are analysed. Notion of superplane schemes is introduced and the type of these schemes is identified. The methods of circuit flow rates should be applied at simulation of superplane schemes at the training facility, while at non-superplane schemes the extreme method where the circuit value is introduced, is more advisable. Fields of extreme method application are determined. Quick method of by-coordinate descent is suggested. The problem of optimum algorithm is considered for both methods

1986-04-01

379

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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, ...

Hansen, Rico H.; Kramer, Morten M.; Enrique Vidal

2013-01-01

380

Lim Guidance Control Systems.  

Science.gov (United States)

The feasibility of control systems for positioning the LIM with respect to the reaction rail without physical contact is examined. Preliminary design analyses are made for several representative systems. Systems for use with both a ferrous or composite re...

J. D. Muhlenberg

1970-01-01

 
 
 
 
381

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

1994-01-01

382

Efficient non-destructive method of control over the frost-resistance of concretes designated for hydraulic engineering structures ????????????? ??????????? ????? ???????? ??????????????? ??????? ???????????????? ??????????  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The author considers the problem of control over the frost resistance as the most important characteristic of concretes designated for hydraulic engineering structures. His method is based on the identification of correlation between the frost resistance and the Poisson ratio. The value of the Poisson ratio is measurable through the employment of the ultra-sound method. The proposed methodology contemplates the following sequence of acts. First, the value of the Poisson ratio of air-dried sam...

Popov Valeriy Petrovich

2012-01-01

383

A national control system  

International Nuclear Information System (INIS)

An effective control of nuclear fissionable material is dependent on three different kinds of control, the industry - laboratory management, a national control system and an international safeguards system. The national systems of control differ greatly between various industrialized countries. Two principal reasons for fact can be mentioned. The type and the amounts for nuclear material may be different depending upon the stage of development of the nuclear industry in the country in question. Another reason may be that the country may wish to establish a very elaborate national system of control in order to minimize the IAEA control as much as possible. The two safeguards agreements between the Agency and Sweden on one hand and the Agency and Japan on the other hand can serve as examples for the understanding of the latitude of the IAEA safeguards system under NPT due to the influence of the national control system. If it thus is apparent that the national control system is strongly interrelated to the international safeguards system it is equally influenced by the control and accountancy systems which exist at the nuclear plants and development laboratories. A detailed study of national control systems and their relations to plant management control would fall outside the scope of this article. Some important features will however be examined. (author)

1975-01-01

384

Control Configuration Selection for Multivariable Descriptor Systems  

DEFF Research Database (Denmark)

Control configuration selection is the procedure of choosing the appropriate input and output pairs for the design of SISO (or block) controllers. This step is an important prerequisite for a successful industrial control strategy. In industrial practices it is often the case that the system, which is needed to be controlled, is either in the descriptor form or can be represented in the descriptor form. Singular systems and the differential algebraic equation (DAE) systems are among these systems. Descriptor systems appear in the variety of fields to describe the practical processes ranging from power systems, hydraulic systems to heat transfer, and chemical processes. The focus of this paper is on the problem of control configuration selection for multivariable descriptor systems. A gramian-based interaction measure for control configuration selection of such processes is described in this paper. The proposed MIMO interaction measure is the extension of its gramian-based analogous counterpart, which has been proposed for the inputâ??output pairing as well as for the controller architecture selection of the processes with the standard state-space form. The main advantage of this interaction measure is that it can be used to propose a richer sparse or block diagonal controller structure. The interaction measure is used for control configuration selection of the linearized CSTR model with descriptor from.

Shaker, Hamid Reza; Stoustrup, Jakob

2012-01-01

385

Thermal-Hydraulic System Study of the Helium Cooled Pebble Bed (HCPB) Test Blanket Module (TBM) for ITER Using System Code RELAP5  

Science.gov (United States)

The HCPB concept has been a European DEMO reference concept for nearly one decade. Detailed thermal-hydraulic study on the control behavior of the whole system is one of the important parts of this development. The thermal-hydraulic effect of the TBM-combined cooling circuit during a cyclic operation in ITER has been studied using the system code RELAP5. The RELAP5 is based on an one-dimensional, transient two-fluid model for the flow of a two-phase steam-water mixture that can contain noncondensable components like Helium. The RELAP5-models are modified to take the cyclic operation of the circulator, heat exchanger, bypass, valves etc in to account. A sequence of operational phases is investigated, starting from the cold state through the heating phase that brings the system to a stand-by condition, followed by typical power cycles applied in ITER. The results show that the implemented control mechanisms keep the inlet temperature to the TBM and the total mass flow rate at the required values through all phases.

Jin, Xuezhou; R, Meyder

2005-04-01

386

CANTHIS, the CANDU neutronic and thermal hydraulic information system: Its development, structure and contents  

International Nuclear Information System (INIS)

This paper addresses the on-going procedures of the development of a database and its contents. The database named as CANTHIS (CANDU Neutronic and Thermal Hydraulic Information System) is originally designed under the technical basis of SQL (Structured Query Language) in order to help the CANDU-related researchers to easily and quickly find the experimental information, as a part of the CASA (CANDU Safety Analysis) project set about by KAERI (Korea Atomic Energy Research Institute). The database is mainly intended to produce thermal-hydraulic experimental data resulted from the CANDU-related facilities around the world and it also includes some neutronics data which are especially from some critical facilities related to CANDU. Because there are some limitations for getting the raw data from each experiment, the system generally gives information with the images of graphs come from literatures comprehensively including all kinds of papers available. As an additional function, CANTHIS offers a digitizing tool converting the images to numerical data. The CANTHIS also includes the useful menus and documents because we intended it to be used by the beginners or students in nuclear engineering field as well as by the specialists for CANDU safety analysis. With the supporting database system such as the CANTHIS, the efficiency of researches for CANDU safety analysis can be enhanced and systematized. (author)

2004-10-04

387

Thermal and hydraulic analysis of the cooling system for the ITER equatorial port plugs  

Energy Technology Data Exchange (ETDEWEB)

Thermo-hydraulic analysis of the equatorial port plug (EPP) is currently being performed by CIEMAT within the framework of the engineering activities related to the ITER port plug diagnostic integration launched by EFDA. This study is focussed on calculating the main hydraulic parameters for the reference cooling circuit, and analyzing different piping configurations, in order to achieve a balanced circuit, this being a key point for obtaining an homogeneous refrigeration of the port plug. It also analyzes the cooling requirements for the Diagnostic Shield Modules (DSM), considering not only the reference circuit design, where the piping cooling circuits run through those parts that need to be cooled, but also a new design proposal which entails a port plug cooling system based on the thermal contact between the DSM and the port plug itself. The overall study represents not only an improvement in the equatorial port plug cooling system design, but also a better understanding of the whole system so as to foresee the weak points that will need to be taken into account in the subsequent detailed design.

Rincon, E. [Association EURATOM - CIEMAT, Avda. Complutense 22, 28040 Madrid (Spain)], E-mail: esther.rincon@ciemat.es; Botija, J.; Garcia, A.; Medrano, M.; Sarasola, X.; Soleto, A. [Association EURATOM - CIEMAT, Avda. Complutense 22, 28040 Madrid (Spain); Ciattaglia, E. [EFDA - Close Support Unit. Boltzmannstr 2, 85748 Garching (Germany); Walker, C. [ITER International Team. Cadarache, Saint Paul lez Durance (France); Doceul, L. [Association EURATOM - CEA, CEA/DSM/DRFC, CEA/Cadarache, Saint Paul lez Durance (France); Balshaw, N. [Association EURATOM -UKAEA, Culham Science Centre, Abingdon (United Kingdom); Petrizzi, L. [Association EURATOM - ENEA, Centro Ricerche, Frascati (Italy)

2009-06-15

388

Thermal and hydraulic analysis of the cooling system for the ITER equatorial port plugs  

International Nuclear Information System (INIS)

Thermo-hydraulic analysis of the equatorial port plug (EPP) is currently being performed by CIEMAT within the framework of the engineering activities related to the ITER port plug diagnostic integration launched by EFDA. This study is focussed on calculating the main hydraulic parameters for the reference cooling circuit, and analyzing different piping configurations, in order to achieve a balanced circuit, this being a key point for obtaining an homogeneous refrigeration of the port plug. It also analyzes the cooling requirements for the Diagnostic Shield Modules (DSM), considering not only the reference circuit design, where the piping cooling circuits run through those parts that need to be cooled, but also a new design proposal which entails a port plug cooling system based on the thermal contact between the DSM and the port plug itself. The overall study represents not only an improvement in the equatorial port plug cooling system design, but also a better understanding of the whole system so as to foresee the weak points that will need to be taken into account in the subsequent detailed design.

2009-06-01

389

Use of Plant Hydraulic Theory to Predict Ecosystem Fluxes Across Mountainous Gradients in Environmental Controls and Insect Disturbances  

Science.gov (United States)

While mountainous areas are critical for providing numerous ecosystem benefits at the regional scale, the strong gradients in environmental controls make predictions difficult. A key part of the problem is quantifying and predicting the feedback between mountain gradients and plant function which then controls ecosystem cycling. The emerging theory of plant hydraulics provides a rigorous yet simple platform from which to generate testable hypotheses and predictions of ecosystem pools and fluxes. Plant hydraulic theory predicts that plant controls over carbon, water, energy and nutrient fluxes can be derived from the limitation of plant water transport from the soil through xylem and out of stomata. In addition, the limit to plant water transport can be predicted by combining plant structure (e.g. xylem diameters or root-to-shoot ratios) and plant function (response of stomatal conductance to vapor pressure deficit or root vulnerability to cavitation). We evaluate the predictions of the plant hydraulic theory by testing it against data from a mountain gradient encompassing sagebrush steppe through subalpine forests (2700 to 3400 m). We further test the theory by predicting the carbon, water and nutrient exchanges from several coniferous trees in the same gradient that are dying from xylem dysfunction caused by blue-stain fungi carried by bark beetles. The common theme of both of these data sets is a change in water limitation caused by either changing precipitation along the mountainous gradient or lack of access to soil water from xylem-occluding fungi. Across all of the data sets which range in scale from individual plants to hillslopes, the data fit the predictions of plant hydraulic theory. Namely, there was a proportional tradeoff between the reference canopy stomatal conductance