On the Static Instability of Liquid Poppet Valves

This paper focuses on flow induced static instabilities occurring in poppet valves. Computational fluid dynamics simulation were performed to gain static characteristics of the poppet valve and to demonstrate the unstable behaviour of the valve. Based on theoretical considerations, a necessary condition for the stable operation is derived. The study indicates that stability can be obtained with proper geometrical design of the valve or by limiting the total compression of the spring. The paper discusses the possible steps to prevent instability and proper spring selection.