STUDY ON CHARACTERISTICS OF PNEUMATIC NOZZLE FLAPPER VALVE CONSIDERING UNSTEADY FLOW FORCE OF JET THROUGH NOZZLE

摘要

Designing a nozzle flapper valve employed in a pneumatic control system with high performance in detail, it is necessary to predict accurately the characteristics of the nozzle flapper valve in advance. This paper deals with the characteristics of the nozzle flapper valve and the effect of the unsteady flow force of the air jet through the nozzle on the characteristics of the nozzle flapper valve is analyzed in the experiments. The experimental results show that the unsteady flow force influences on the frequency response of the nozzle flapper valve in the low frequency region. It is concluded that the design of the nozzle flapper valve should be made, taking account of the unsteady flow force of the air jet through the nozzle.