Numerical simulation of the multiscale cavitation flow in a hydraulic slide valve

Cylindrical slide valves are commonly used in various hydraulic control systems. Due to their working characteristics, cavitation often occurs when hydraulic oil flows through the valve port, which threatens the stability of the entire hydraulic system. Therefore, the study of cavitation phenomena inside valves has important practical significance. This study used the Euler-Lagrange bidirectional coupled multi-scale cavitation model to simulate the cavitation phenomenon inside a cylindrical slide valve numerically. We examined the specific morphological characteristics of cavitation occurring at various positions within the valve and investigated the influence of oil temperature on the size of microbubbles. The results indicate that the cavitation morphology at the sharp edge of the valve port is greatly affected by the temperature of the hydraulic oil. It is a traveling cavitation at low temperatures, and as the oil temperature increases, it gradually transforms into cloud cavitation. The macroscopic cavitation bubble shape inside the low-pressure chamber of the valve gradually stabilizes with the increase of inlet oil temperature. The Sauter diameter of micro-bubbles inside the valve decreases with increasing oil temperature. In addition, the inlet oil temperature will have a certain degree of impact on the mass-weighted diameter distribution of microbubbles flowing out from the valve outlet. Therefore, in actual working conditions, removing air bubbles within a specific size range in hydraulic oil is recommended to reduce the adverse effects of hydraulic oil cavitation.