Experimental and numerical study of back-cooling car-seat system using embedded heat pipes to improve passenger's comfort

Graphical abstract: Heat pipe assembly (a) with the insulation layer (b) without the insulation layer; and (c) thermal manikin test on the heat pipe chair. - Highlights: • A new back cooling system for a car seat using embedded heat pipes was modeled numerically. • The heat-pipe seat model was experimentally validated using heated thermal manikin. • An integrated heat pipe model and bio-heat model was used to predict local thermal comfort. • The heat pipe system reduced the back skin temperature by 1 °C compared to seat without heat pipes. • The heat pipe system increased the overall thermal comfort of the passenger by 30%. - Abstract: This work develops a back-cooling system for a car seat using seat embedded heat pipes to improve passenger comfort. The heat pipe system utilizes the temperature difference between the passenger back and the car cabin air to remove heat from the human body and enhance the comfort state. The developed seat heat-pipe model was validated experimentally using a thermal manikin with controlled constant skin temperature mode in a climatic chamber. Good agreement was found between the measured and the numerically predicted values of base panel temperature. By integrating the validated heat pipe with a bio-heat model, the back segmental skin temperature as well as the overall thermal comfort was predicted and compared with the conventional seat case without the heat pipe system. The heat pipes were able to reduce the skin temperature by 1 °C and to increase the overall thermal comfort of the body by 30%. In addition, a parametric study was performed to determine the optimal number of heat pipes that ensure the thermal comfort of the passenger.