Abstract: In view of the limitations of the present degreasing process commonly used in the production of the air-conditioning radiator, we propose an energy-saving and environmentally-friendly vacuum drying degreasing method and investigate the temperature field of the vacuum drying degreasing tank.Based on the DO model in FLUENT,the simulation results are as follows: Firstly, in the vacuum tank stably heated by a heat source, the suitable position of fins arranged in the two-layer interval is in the lower half of the tank, where the temperature difference is small and the temperature difference is about 7℃.Secondly, the range of effective heating zone is discussed, Then the theoretical model of total power P of the heat source and volume V of the tank are established by means of control variable method, which has certain theoretical guiding significance for the design of degreasing tank.