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With the increase in fuel prices and the increasingly strict environmental legislations regarding CO₂ emissions, reduction of the total energy consumption of our society becomes more important. Passenger vehicles are partly responsible for this consumption due to their strong presence in the daily life of most people. Therefore reducing the impact of cars on the environment can assist in decreasing the overall energy consumption. Even though several fields have an impact on a passenger car's performance, this paper will focus on the aerodynamic part and more specifically, the wake behind a vehicle. By definition a car is a bluff body on which the air resistance is for the most part driven by pressure drag. This is caused by the wake these bodies create. Therefore analyzing the wake characteristics behind a vehicle is crucial if one would like to reduce drag.

Under a global impulse for less man-made emissions, the automotive manufacturers search for innovative methods to reduce the fuel consumption and hence the CO2-emissions. Aerodynamics has great potential to aid the emission reduction since aerodynamic drag is an important parameter in the overall driving resistance force. As vehicles are considered bluff bodies, the main drag source is pressure drag, caused by the difference between front and rear pressure. Therefore increasing the base pressure is a key parameter to reduce the aerodynamic drag. From previous research on small-scale and full-scale vehicles, rear-end extensions are known to have a positive effect on the base pressure, enhancing pressure recovery and reducing the wake area. This paper investigates the effect of several parameters of these extensions on the forces, on the surface pressures of an SUV in the Volvo Cars Aerodynamic Wind Tunnel and compares them with numerical results.

Electric vehicles are considered one of the most promising solutions in the transport sector to curb greenhouse gas emissions and combat the effects of climate change. However, their performance in cold climates is adversely affected due to battery and cabin climatization resulting in reduced driving range. This study investigates the effect of heat transfer to the thermal masses on the cabin temperature in a passenger car, and the influence of insulation on different surfaces while climatizing under low ambient temperatures. A conjugate heat transfer model of the cabin was systematically developed, along with a framework to perform transient cabin heat-up simulations. The scenario considered was a vehicle driving at 50 km/h at -7°C for 40 minutes. Six configurations with insulation on different surfaces, including a fully insulated cabin, and four thermal resistance magnitudes were studied.