On the Stability of a Poppet Valve with an Elastic Support : 2nd Report, Considering the Effect of both the Inlet and the Outlet Piping System

Abstract

In a previous report, the author discussed the stability of a conical hydraulic poppet valve with an elastic support. There he considered chiefly a valve having only inlet piping. In this paper, the results of further investigations are reported on the same type of valve, considering both inlet and outlet piping. Some theoretical considerations are first developed using the characteristic equation of this system which has already been derived in the previous report. Some experiments were conducted varying the length of the inlet and outlet piping. The experimental results agree fairly well with the theory. The following conclusions are obtained ; (1) the outlet piping increases the frequency range in which instability occurs, (2) very short inlet piping may increase the instability range.