Experimental analysis of different ventilation concepts for the passenger compartment of a generic car

Abstract

Novel ventilation systems as well as state of the art mixing ventilation (MV) were installed and investigated in a generic car mock-up under cooling conditions. The cabin of the full-scale facility comprises displacement ventilation air inlets at floor and ceiling level, which can be used solely or combined and allow for thermal comfort benefits, well-known from studies in aircraft cabins. Surface and fluid temperatures were analysed with an infrared camera and local temperature sensors. Omnidirectional velocity probes were used to capture the fluid velocities and temperatures in the vicinity of thermal passenger dummies. Regarding the comfort relevant flow parameters, mixing ventilation shines out with high air velocities and turbulences levels, but homogeneous temperature distributions. The novel ventilation concepts, on the other hand, allow for comfortable velocity and turbulence levels, but tend to comfort critical temperature stratifications, except for ceiling based displacement ventilation. Further differences are observed concerning the heat removal efficiency, which is highest for CDV and the heat exchange with the surrounding, which is highest for MV.