Wind tunnel tests on heavy road vehicles: Cross wind induced loads—Part 2

The sensitivity of heavy road vehicle aerodynamic coefficients to different testing parameters (scenario, vehicle type and turbulence intensity) is experimentally evaluated in this paper through wind tunnel experiments. The first part of the paper has investigated the aerodynamic loads (both stationary and non-stationary) acting on a high-sided lorry (VAN) in a flat ground scenario. The mean aerodynamic coefficients, the flow pattern around the vehicle and the aerodynamic admittance function have been assessed and compared for different wind turbulence conditions (boundary layer simulations). The present paper instead investigates the influence of the infrastructure scenario (flat ground, embankment, single and double viaduct), of the exposition (upwind or downwind) and of a trailed unit on the aerodynamic loads acting on the vehicle. Moreover, the mean aerodynamic coefficients and the aerodynamic admittance function of the high-sided lorry considered in the first part are compared with the ones of other heavy vehicles (tank truck, tractor–semitrailer combination and tractor–trailer combination) to assess the influence of the vehicle geometry.

► An extensive wind tunnel experimental campaign has been performed on a heavy-vehicle model (VAN).
► Effects of yaw angle and boundary layer on force and pressure coefficients were investigated.
► Main effects due to yaw angle were found at the windward upper edge.
► Main effects due to boundary layer were found at high yaw angles, especially on side and lift force.