FLAT-TUBE HEAT EXCHANGER MODELING UNDER FROSTING CONDITIONS FOR AN ELECTRIC VEHICLE HEAT PUMP

摘要

Reversible heat pumps for electric vehicles are being developed by the car industry to address cabin heatingrnand improve energy efficiency compared to electric heaters. For this new application, the front microchannelrnheat exchanger (MCHX or flat-tube heat exchanger) of an A/C system acts as an evaporator on the heatrnpump mode and can operate under frosting conditions. The MCHX is particularly sensitive to frosting.rnConsequently, a MCHX model that can predict performances under frosting conditions is required. Thisrnpaper presents a dynamic pseudo 3D model of a MCHX including frost growth. Frost is modeled as a porousrnlayer that is subject to heat and mass transfer. The model successfully predicts thermal performances for nonuniformrnfrost growth. The model needs now wider experimental validation and could be used as a designrntool.