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Heat exchangers with Phase Change Material (PCM) are finding more energy storage applications for both Internal Combustion Engine Vehicles (ICEVs) and Electric Vehicles (EVs). These applications include cold storage evaporators for stop-start cars, thermal storage system for EV cabin heating and cooling, and other Heating, Ventilation, and Air Conditioning (HVAC) and Power Train Cooling (PTC) peak load shaving applications. The energy stored in a PCM heat exchanger is typically charged/discharged using refrigerant, coolant, or air, depending on the system design of different applications. Due to the low thermal conductivity of state-of-art PCM, the PCM heat exchangers generally rely on aluminum fins to enhance the speed of charging and discharging of the stored energy. Different fin shape, height and density will result in different PCM freezing/melting rate.

Spot, or distributed, cooling and heating is an energy efficient way of delivering comfort to an occupant in the car. This paper describes an approach to distributed cooling in the vehicle. A two passenger CFD model of an SUV cabin was developed to obtain the solar and convective thermal loads on the vehicle, characterize the interior thermal environment and accurately evaluate the fluid-thermal environment around the occupants. The present paper focuses on the design and CFD analysis of the energy efficient HVAC system with spot cooling. The CFD model was validated with wind tunnel data for its overall accuracy. A baseline system with conventional HVAC air was first analyzed at mid and high ambient conditions. The airflow and cooling delivered to the driver and the passenger was calculated. Subsequently, spot cooling was analyzed in conjunction with a much lower conventional HVAC airflow.