Research on Refrigerant Flow Noise under Sudden Stop of Automobile Air Conditioning

This paper studies the Mid-low frequency refrigerant flow noise generated by the automobile air conditioning system when the automobile is idling and stalling. Combining bench test and fluid simulation, the principle analysis is carried out and then optimized by expansion valve and its inlet high-pressure pipeline. A scheme for applying pipeline muffler to solve this kind of noise is proposed, and combined with the existing experience to improve the scheme, the final scheme is obtained without affecting the original performance requirements of automobile air conditioners. For this kind of unsteady noise, a new sound quality evaluation parameter SQM is proposed to predict the subjective performance of its sound quality, which has better prediction accuracy.