Abstract: For the fixed frequency air conditioner, with the gradual increase of ambient temperature, the cooling capacity gradually decreases. In order to solve this problem, based on the technology of increasing Enthalpy by air jet, the specific reasons for increasing the high temperature cooling capacity of the system are obtained through theoretical analysis, and the effects of the key parameters of the system and the aperture of the compressor air supply port on the refrigeration capacity are analyzed and verified in detail. Finally, it is concluded that increasing the liquid level in the flash evaporator can effectively improve the cooling capacity; at the same time, reducing the diameter of the air supply port of the compressor can improve the cooling capacity and reduce the power of the whole machine. Through the implementation of the above scheme, under the same configuration and the same displacement, the refrigeration capacity of the constant frequency jet enthalpy increasing air conditioning system is 10.8% higher than that of the ordinary air conditioning system at 46 ℃.

Key words: Enhanced vapor injection, Refrigeration mode, High temperature refrigerating capacity, Gas supply port, Aperture, Liquid level