الفهرس Only 14 pages are availabe for public view
 |  | from | 123 |  |  |
| | | from | 123 | | |
Abstract
This thesis is concerned with studying the performance of two cartridge relief valves, namely a conventional pilot-operated relief valve and a soft relief valve.
The soft relief valve is a new type of relief valves, which is characterized by controlling the rate of pressure rise and eliminating the pressure peaks. Thus, the soft relief valve protects the hydraulic components from pressure transients and can allow the use of higher operating pressures without causing fatigue failure to theses components. Two mathematical models are developed to study the dynamic behaviors of the two valves under consideration Using these models, the behaviors of the two valves are simulated using the Simulink® software package. An experimental setup is constructed in the Fluid Mechanics Lab (Faculty of Engineering, Alexandria University) to obtain reliable experimental measurements to study the dynamic behavior of the valves and to verify the results of the Simulink models. The transient response is obtained by recording the system pressure using a data acquisition system. The dynamic responses of the valves are recorded at different operating conditions to cover the expected operating range. The mathematical models are validated using the experimental results. The dynamic responses of the soft relief valve and the conventional pilot-operated relief valve are discussed and compared to reveal the advantages of the soft relief valve. Finally, a parametric study is conducted using the mathematical models to investigate the effects of various parameters on the dynamic responses of both valves in an attempt to improve the performance of both valves.