Tests for vehicle aerodynamics in the cryogenic wind tunnel Cologne DNW-KKK

With the increasing speed of new generations of high speed trains their geometry is becoming increasingly important and the aerodynamic design has to be considered in greater detail. Particularly the train´s crosswind sensitivity is a problematic in nature and has to be considered accordingly. Earlier measurements by means of particle image velocimetry (PIV) in smaller wind tunnels showed the presence of a strong vortex at the leeward side of the model. To address this issue, PIV tests and also force measurement were made on a generic high speed train model. The scaling factor of the model was 1:10. Contour and geometric ratios are nearly similar to the German ICE1 train. For the investigation of force and torque data the ICE-Model was adapted to the half model-balance of cryogenic wind tunnel Cologne (KKK). These results are presented herein. The boundary layer thickness is an essential parameter influencing the measurements. In case of semi-span model tests this problem is solved by using a peniche (standoff) between support and fuselage. The model-ground plane distance was varied in order to determine it´s influence on the ICE-model measurements.