Paper Title
Experimental Method of Solar Vehicle Drag Coefficient Determination

The article focuses on the research on the aerodynamics of the solar vehicle Eagle Two, constructed by the students of Lodz University of Technology for the sake of international solar car races such as Ilumen European Solar Challenge and Bridgestone World Solar Challenge. It presents an empirical method for determination of the vehicle power demand (due to aerodynamics and rolling friction) which allows estimation of vehicle drag coefficient. According to the experiment the drag coefficient of Eagle Two is equal 0.23. The verification of the result was performed based on the propulsion system efficiency. According to the manufacturer the efficiency of the electric motors is equal 88%. The authors experimentally determined the power consumption of the vehicle. The methods allow estimation of power consumption and demand excluding influence of the road inclination, hence the results are corresponding to the flat road testing. It was calculated that the power demand of the Eagle Two car is 3 447 W, whereas its actual consumption is 4 032 W. The value of the efficiency of the propulsion system obtained based on the experiment equals 85%. Index Term - Aerodynamics, drag coefficient, drag force, experimental method, power demand, vehicle