A Closed Loop Full-Scale Automotive Climatic Wind Tunnel for Vehicle Environment Simulation

Abstract

Abstract This paper describes the simulation of vehicle natural climatic environment in a closed loop full-scale automotive climatic wind tunnel. The tunnel simulates wind, rain, and temperature for several road conditions. It generates under controlled heat loading, wind speeds of up to 50kph with different approach boundary conditions, rainfalls from drizzle to cloudburst and road inclines up to 15° in any direction. The design and optimization process of the tunnel functions is outlined and examples of its use in vehicle development are given. The size constraint and the need for a compact design are important features of the tunnel. The tunnel provides an important test bed for close scrutiny of the relationship between rain ingress, vehicle speed, road condition, heat loading and vehicle geometry. The tunnel can also be used to study vehicle thermal management, vehicle thermal comfort, engine cold starting, and wipers efficiency in severe cold weather. Computational Fluid Dynamic (CFD) simulation is used to optimize and asses the performance of a number of key tunnel components. The resulting tunnel is approximately 9.5m in length, 9.5 m in height and 3 m in width.