The reduction of accident risk for high sided road vehicles in cross winds

Abstract Wind tunnel tests have been performed to investigate methods of reducing the accident risk (the number of hours a year that the accident wind speed is exceeded) for high sided road vehicles in high winds. Measurements were made of the aerodynamic forces acting on a 1/50th scale vehicle model in a turbulent flow behind wind fences of various geometry and with the upper corners of the trailer rounded to various radii. Extreme forces were also measured for the model behind a wind fence. The results showed the drastic reduction in the accident risk achieved by the use of wind fences due to the large reductions of the aerodynamic forces acting on the vehicle. However, only a modest reduction resulted from the rounding of trailer corners due to the strong Reynolds number dependency of the force coefficients.