Investigation on self-excited vibration in a deep-sea balance valve via 3D poppet motion simulation

The seawater hydraulic variable ballast system (SHVBS) is utilized for dynamically adjusting the buoyancy of submersibles, in which the balance valve acts as a critical component. However, vibration-induced dynamic instability of the valve severely restricts the high-precision operational performance of submersibles. To address the challenge of predicting the three-dimensional motion and collisions of the balance valve poppet and to investigate its vibration characteristics, this study employs a combined approach of three-dimensional CFD simulation and experimental analysis. Results demonstrate that the vibrational energy of the balance valve primarily originates from radial impacts between the poppet and the push rod. The impact frequency of the poppet increases with rising backpressure, and restricting the radial motion of the poppet can effectively improve the vibration characteristics of the balance valve under various working conditions. The findings of this study offer valuable insights for improving the vibration performance of similar types of valves.