Dynamics and vibration of control valves under flow-induced vibration are analyzed. Hydrodynamic load characteristics and structural response under flow-induced vibration are mainly influenced by inertia, damping, ela...Dynamics and vibration of control valves under flow-induced vibration are analyzed. Hydrodynamic load characteristics and structural response under flow-induced vibration are mainly influenced by inertia, damping, elastic, geometric characteristics and hydraulic parameters. The purpose of this work is to investigate the dynamic behavior of control valves in the response to self-excited fluid flow. An analytical and numerical method is developed to simulate the dynamic and vibrational behavior of sliding dam valves, in response to flow excitation. In order to demonstrate the effectiveness of proposed model, the simulation results are validated with experimental ones. Finally, to achieve the optimal valve geometry, numerical results for various shapes of valves are compared. Rounded valve with the least amount of flow turbulence obtains lower fluctuations and vibration amplitude compared with the flat and steep valves. Simulation results demonstrate that with the optimal design requirements of valves, vibration amplitude can be reduced by an average to 30%.展开更多
A new electro-hydraulic exciter that consists of rotary valve and micro-displacement double-functioned hydraulic cylinder was proposed to realize different kinds of waveforms.Calculated fluid dynamics(CFD) simulation ...A new electro-hydraulic exciter that consists of rotary valve and micro-displacement double-functioned hydraulic cylinder was proposed to realize different kinds of waveforms.Calculated fluid dynamics(CFD) simulation of rotary valve orifice reveals that orifice exists the two-throttle phenomenon.According to the finding,the revised flow area model was established.Vibration waveforms analysis was carried out by means of mathematic model and the related experiments were validated.Furthermore,as a new analysis indicator,saturation percentage was introduced first.The experimental results indicate that the revised flow area model is more accurate compared to the original one,and vibration waveforms can be optimized through suitable spool parameters and the revised cylinder structure.展开更多
文摘Dynamics and vibration of control valves under flow-induced vibration are analyzed. Hydrodynamic load characteristics and structural response under flow-induced vibration are mainly influenced by inertia, damping, elastic, geometric characteristics and hydraulic parameters. The purpose of this work is to investigate the dynamic behavior of control valves in the response to self-excited fluid flow. An analytical and numerical method is developed to simulate the dynamic and vibrational behavior of sliding dam valves, in response to flow excitation. In order to demonstrate the effectiveness of proposed model, the simulation results are validated with experimental ones. Finally, to achieve the optimal valve geometry, numerical results for various shapes of valves are compared. Rounded valve with the least amount of flow turbulence obtains lower fluctuations and vibration amplitude compared with the flat and steep valves. Simulation results demonstrate that with the optimal design requirements of valves, vibration amplitude can be reduced by an average to 30%.
基金Project(51275499)supported by the National Natural Science Foundation of ChinaProject(2013CB035404)supported by the National Basic Research Program("973" Program)of ChinaProject(51221004)supported by the Science Fund for Creative Research Groups,National Natural Science Foundation of China
文摘A new electro-hydraulic exciter that consists of rotary valve and micro-displacement double-functioned hydraulic cylinder was proposed to realize different kinds of waveforms.Calculated fluid dynamics(CFD) simulation of rotary valve orifice reveals that orifice exists the two-throttle phenomenon.According to the finding,the revised flow area model was established.Vibration waveforms analysis was carried out by means of mathematic model and the related experiments were validated.Furthermore,as a new analysis indicator,saturation percentage was introduced first.The experimental results indicate that the revised flow area model is more accurate compared to the original one,and vibration waveforms can be optimized through suitable spool parameters and the revised cylinder structure.
