Study of the Two-Phase Flow Characteristics of a Damping Orifice in an Oleo-Pneumatic Shock Absorber

The oleo-pneumatic shock absorber involves a complex two-phase flow in the working process. In this paper, simple model was established, and volume-of-fluid (VOF) adopted to accurately simulate distribution of field through commercial software FLUENT 2020 R2. accuracy simulation verified by method engineering damping force estimation, error numerical results compared with estimation 7–8%. By simulation, influence different orifice lengths diameters on maximum pressure, temperature, velocity oil inside studied. showed that increase length, rate decreased. temperature decreased first then increased, but overall effect small. However, according volume fraction contour, gas–liquid an larger than 15 mm more chaotic. Increasing diameter had great impact absorber. were sharply reduced, continued rise. These research can provide reference for optimization design absorbers.