CFD for the automotive industry

Aerodynamics

A lot is published about the simulation of complete vehicles. Also the aerodynamic details of vehicle components is of great interest. This example shows the transient flow regime about an external mirror.

The simulation results are used to optimize the mirror such that rain and dust particles are diverted away from the glass. In this way the mirror remains free of dirt. Also the reduction of acoustics and the stability of the glass is of concern.

Throttles and valves

The regulation and control of flow conditions require the measurement of forces or temperatures. Simulations deliver these values without having to build prototypes.

In a lot of cases the measuring probes can be optimized such that their influence on the flow regime is minimal. Also the positioning of the probes can be investigated in order to avoid placing them wrongly.

Filters

Several kinds of filters are used in vehicles such as fuel filters, oil filters and air filters.

Usually the main aim of development is to increase the efficiency of filtration and the reduction of the pressure loss.

The figures presented here show the flow conditions within a lorry's air filter. The pressure distribution is shown by a contour plot in Pa. whereas the steam lines are coloured by the flow velocity in m/s.

For the volume flow rate of interest the predicted total pressure drop is 35 mbar. The measured pressure drop is 34 mbar.