Abstract
This paper describes the extension of the soiling simulation module in PowerVIZ, the visua-lizer of the CFD-tool PowerFLOW®, to enable realistic modeling of stone chipping. To start with, the basics of computing the movement of particles in a given flow field are explained briefly. The status is demonstrated on some examples for soiling and simulating a windshield washer system. The bulk of the paper focuses on the extensions necessary to apply this me-thod to stone chipping. First of all this requires the inclusion of reflecting surfaces with a scatter on the outgoing di-rection as well as a surface normal momentum loss due to imperfect elastic collision. Further, the momentum transfer from surfaces moving relative to the vehicle body, like the floor and rotating wheels, has to be accounted for. Of paramount importance for the practical application is the knowledge of realistic initial conditions. For this purpose the ejection of stones from the front wheels was recorded with high-speed cameras and evaluated in terms of velocity magnitude, direction and scatter. The damage probability is judged by the distribution of the locally surface normal momentum of particles at the instance of their impact. First results of identifying critical regions are con-firmed by field tests.
Keywords: Aerodynamics, CFD, Simulation, Soiling, Stone Chipping