The cavitation effect of lubricating film has a significant impact on the seal performance of hydrodynamic pressure mechanical seals.Kerosene-based magnetic fluid lubrication upstream pumping mechanical seal with inclined groove was taken as the research object.By considering the cavitation heat effect as well as the viscous temperature effect,the calculation model of lubricating fluid film was established to study the influences of working conditions and structural parameters on the seal performances using the volume fraction of gas phase in the liquid film as an indicator,and the results were compared with those based on the model only considering the viscous temperature effect.It is found that,due to the cavitation heat model considering the variation of saturated vapor pressure of liquid film medium with temperature,the opening force,leakage rate and volume fraction of vapor phase when considering the thermal effect of cavitation are smaller than the corresponding results when considering the viscosity-temperature effect only,but the variation regularity of each parameter is basically the same under the two conditions.The cavitation effect is enhanced by increasing the rotational speed and the groove diameter ratio,while the cavitation effect is weakened by increasing the inlet pressure,film thickness,radial angle and number of grooves.An increase in rotational speed,groove depth,radial angle,and groove diameter ratio will lead to an increase in leakage rate,while an increase in inlet pressure and groove number can improve sealing performance.