Simulation study on noise reduction effect of porous material on electronic expansion valve

To reduce the flow-induced noise caused by the refrigerant in the refrigeration system and improve the comfort of air conditioning, porous materials are used to rectify the refrigerant in the refrigeration system. To simulate the flow field characteristics and flow-induced noise level in the electronic expansion valve before and after adding porous material at the outlet of the electronic expansion valve orifice for rectifying, the commercial simulation software Fluent is applied, which adopts the mixture multiphase model and cavitation model, and compile UDF to set the momentum source term in the porous medium region. The results show that adding porous material can rectify the refrigerant in the electronic expansion valve without changing the cooling capacity of the refrigeration system. The flow-induced noise generated in the porous material rectified electronic expansion valve is reduced in many directions. After rectification, the gas phase distribution in the electronic expansion valve is more uniform. The turbulent kinetic energy intensity at the outlet can be reduced to 25% of the originally designed electronic expansion valve; the bubble bursting phenomenon can be effectively inhibited. The noise reduction effect of porous material is suitable for the electronic expansion valve under a small opening and is more evident in the high-frequency noise.