Numerical Simulation of Rainwater Management in Car Climatization

In this paper, the development of numerical droplet wall interaction models for the rainwater management in a car climatization unit has been performed. Moreover the whole rainwater separation process has been simulated by using the new models within a commercial CFD program.

To describe the droplet wall interaction processes more accurate new correlations of the occurring phenomena and new numerical models had to be developed. Therefore a new procedure has been proposed. In spite of doing experiments to investigate the processes in droplet wall interactions Direct Numerical Simulation was used to calculate single droplet wall interaction phenomena in detail. By means of the gained results new correlations describing the whole processes for a wide range of geometries and property values could be derived. By using this new correlations numerical models have been developed and implemented in the commercial CFD program SWIFT. As a result, the water separation process in the waterbox can now be simulated much more accurately.