A two-dimensional simplified model was used to explore the influence factors of two phase flow oscillation heat transfer process in a oil chamber. Through a serious of numerical simulation

it is shown that the two phase flow in the oil chamber is a highly disordered asymmetric flow. In addition to the two order motion of the piston to produce the oil injection deviation

the pressure fluctuation caused by the movement of the oil plume up and down will also make the oil plume tilted

causing the spray to deviate from the chamber inlet. According to the study

the compulsory oscillation caused by the piston motion is a decisive factor to influence the oil flow and heat transfer characteristics in the chamber. The fluctuation frequencies of the filling ratio and surface heat transfer coefficient are fully consistent with the piston motion frequency.Moreover

the fuel injection rate and the piston speed have a significant effect on the filling ratio and heat transfer coefficient

but these factors may not be a single effect but mutual coupling. The matching degree of the spray velocity into the oil chamber and the maximum piston speed may be a key factor to influence the filling ratio and heat transfer coefficients. When the spray absolute velocity is close to or greater than the maximum piston velocity

the ideal filling ratio and heat transfer cofficient will be achieved.