Abstract
In recent years, the drive current applied to acting on nozzle flapper valves has been reduced to save the electric power and the drive force acting on flappers has been lowered to approximate the level of the amount of flow jet force on flapper. As a result, the dynamic characteristics of pneumatic nozzle flapper are influenced, because the flow jet force changes the flapper displacement. So it is necessary to analyze the influences of flow jet force on nozzle flapper system.
In this paper a simplified model of flow jet force on flapper is proposed. The model is coincides with results of experiments in certain conditions. The influences of flow jet force on flappers have been experimentally measured by frequency response tests. The results of experiment, the effects of flow jet force on flapper reduce in high frequency domain. Indicate the model we proposed is practical. We think this model will be beneficial to analysis and design of nozzle flapper valves.
