Using GOTHICTM and RAVEN to Explore Thermal-Hydraulic System Response

2019 ◽  
Author(s):  
J. Lane ◽  
P. Skelton
Keyword(s):  
Hydraulic System ◽  
System Response

scholarly journals Research on dynamic response of subsea control system based on partial correlation analysis

2021 ◽  
Vol 39 (4) ◽  
pp. 847-857
Author(s):  
Peng Jia ◽  
Zhehua Zhang ◽  
Xiangyu Wang ◽  
Yongzhe Qu ◽  
Hao Zhang ◽  
...  
Keyword(s):  
Hydraulic System ◽  
Partial Correlation ◽  
Circuit Simulation ◽  
Simulation Models ◽  
System Response ◽  
Single Factor ◽  
Response Curves ◽  
Factors Affecting ◽  
Object A ◽  
Control Response

In this article, taking a specific underwater hydraulic system as the research object, a closed loop circuit and a closed non-loop circuit simulation models are established; and through a single factor analysis, the interior factors such as different pipeline damping settings, underwater accumulators and actuators, and external factors such as water depth and return distance are analyzed. System response curves of these factors are obtained. Based on the single-factor simulation data, the partial correlation theory is used to analyze the correlation of the influencing factors of the control response for the underwater hydraulic system, and the order of the main factors affecting the control response of the underwater hydraulic system is obtained, which provides a reference for improving the response of the underwater hydraulic system.

Fluid Property Effects on Power Consumption in a Hydraulic System at Low Temperatures

2020 ◽  
Author(s):  
Paul Michael ◽  
Cecilia Dai ◽  
Kimberly Rodriguez
Keyword(s):  
Low Temperature ◽  
Power Consumption ◽  
Low Temperatures ◽  
Hydraulic System ◽  
Rotational Frequency ◽  
Input Power ◽  
Operating Conditions ◽  
System Response ◽  
Hydraulic Systems ◽  
System Power

Abstract Hydraulic systems that are operated outdoors during winter can be exposed to extreme low temperatures. Low temperature thickening of the hydraulic fluid can increase power consumption, cause pump cavitation, and stall system actuation. In this study, the response time and power consumption of a hydraulic vehicle restraint system that is used outdoors year-round was evaluated at low temperatures. This safety device incorporated proximity switches that triggered a machine “fault” when the time delay between the locked and unlocked positions exceeded 8 seconds. Straight- and multi-grade ISO VG 32 and 46 fluids were compared in the device. The multi-grade oils were able to function at a lower temperature without faulting. The effect of system operating conditions and fluid properties on pump input power was evaluated. The input power was determined from measurements of pump rotational frequency and torque. Pump torque increased as the oil temperature decreased. As a result, low-temperature operating conditions resulted in a higher system power requirements. An empirical model was developed to investigate the effects of turbulent and laminar flow conditions on the hydraulic system power requirements. A comparison of model standard errors revealed that viscosity-dependent laminar losses had a greater impact on system performance than density-dependent turbulent losses. Since the viscosity coefficients of the fluids were very high at the test temperature, it was theorized that pressure drop in the hydraulic lines was affecting system response. Hydraulic system simulations were conducted via Automation Studio. Cylinder retraction velocities were evaluated with larger ID cap- and rod-side hoses. Increasing the cap-side hose diameter enhanced the low temperature performance of the system. Changes to the rod-side hose had minimal effect. These results provide new insights for system design and the formulation of hydraulic fluids used in extreme low temperature operations.

scholarly journals Research on 760mm Hot Tandem Mill Hydraulic AGC Control System

2011 ◽  
Vol 2-3 ◽  
pp. 18-23
Author(s):  
Kun Tong ◽  
Ni Ke ◽  
Ming Zhe Che ◽  
Jin Сhun Song
Keyword(s):  
Mathematical Model ◽  
Working Conditions ◽  
Production Line ◽  
Hydraulic System ◽  
Pid Controller ◽  
Sheet Thickness ◽  
System Response ◽  
Fuzzy Pid ◽  
Fuzzy Pid Controller ◽  
The Mathematical Model

Through analyzing the 760mm hydraulic AGC production line of a Shandong factory, the characteristics, compositions and the mathematical model of hydraulic system of the hydraulic AGC are introduced. Based on those the system performance is analyzed on the working conditions by simulations through introducing the PID and fuzzy PID controller. The simulation analysis concluded that the system response time and overshoots with the fuzzy PID controller were better than before, which is in flavor of the production line commissioning and eventually running. The performance of AGC system affects the controlling accuracy of sheet thickness and yield of sheet directly. In order to accommodate the requirement of market and improve the competition of product, a steel plant from Shandong province entrusts relevant department to develop a set of hydraulic system, which is being debugged at present. Our paper mainly introduces the structure and feature of the system. With the mathematical model that accord with the working conditions being founded and PID and fuzzy PID based on the mathematical model being added, We have simulated the system using the software of MATLAB/SIMULINK, which supplies corresponding theoretical basis for the system’s final operation [1].

scholarly journals SIMULASI PEREDAMAN GETARAN PADA PEGAS KATUP (VALVE SPRING) SISTEM HIDROLIK DENGAN METODE PID MEMANFAATKAN SIMULINK MATLAB

2020 ◽  
Vol 5 (1) ◽  
pp. 1-10
Author(s):  
Keszya Wabang ◽  
Ali Warsito ◽  
Andreas Christian Louk
Keyword(s):  
Hydraulic System ◽  
The Other ◽  
Stable System ◽  
System Response ◽  
Vibration System ◽  
Vibration Damper ◽  
Valve Spring ◽  
Integral Constant ◽  
Simulation Results ◽  
Excitation Force

A simulation of damping vibration on valve spring hydraulic system has been done. This research is a study of the simulation that aims to control excess vibration on valve spring hydraulic system as a result of excitation force that is affected by the changes of pressure periodically, to produce a stable system. The simulation performed by using Matlab simulink with applying a PID method (P, PD, PI and PID) and noticed to variations of proportional constant (Kp), integral constant (Ki) and the derivative constant (Kd). The simulation results obtained show that by combining these three constants Ki, Kp and Kd can dampen the vibration better. For the total excitation force, using the value of Kp = 106, Ki = 7 x 106 and Kd = 6 x 104 can provide damping vibration system response on valve spring with a rise time of 1.2119 s, settling time of 1.2792 s, stable at setpoint 1, error steady state 0% and a small maximum overshoot of 0.3309. This is the result of a stable system response and best compared to the other combinations of the constant values.   Keywords : vibration, damper, valve spring, hydraulic system, PID method.

IMPROVING ELECTRO-HYDRAULIC SYSTEM PERFORMANCE BY DOUBLE-VALVE ACTUATION

2016 ◽  
Vol 40 (3) ◽  
pp. 289-301 ◽  
Author(s):  
Yanhong Bai ◽  
Long Quan
Keyword(s):  
Hydraulic System ◽  
Dynamic Performance ◽  
High Flow ◽  
System Response ◽  
Hydraulic Control ◽  
Servo Systems ◽  
Narrow Bandwidth ◽  
Advanced Control ◽  
Hydraulic Servo ◽  
Valve Actuation

Restricted by narrow bandwidth of the existing high-flow servo valves, dynamic performance of high-flow electro-hydraulic servo systems can only be enhanced to a certain extent by advanced control algorithms. This paper proposes a new hydraulic control circuit, in which two valves are arranged in parallel to control the actuator jointly. Frequency response of the equivalent valve is raised and thereby the performance of high-flow electro-hydraulic servo systems can be improved. A model of the proposed system is built and the principle of improving system dynamic performance using the new circuit is analyzed. Simulation results show that double-valve actuation schemes can quicken system response and increase system bandwidth regardless to if the two valves have the same or different behaviors.

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