Alistair Duff, for technical assistance Mr. Andrew Crockett, for strain gauge assistance
A-PILLAR MODELLING 17.1 A-PILLAR INFLUENCE
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- 17.2 GAMBIT: MODELLING
17. A-PILLAR MODELLING17.1 A-PILLAR INFLUENCEAlthough the design optimization efforts proved successful with regards to the wing mirror being positioned on a flat plate it is difficult to determine whether or not the same benefits would be produced with the wing mirror mounted on the A-Pillar. For this reason it seemed constructive to model the wing mirror mounted on the A-Pillar, with the aim of better understanding the flow characteristics over the area and to make a comparison between the values of drag obtained from each CFD model. 17.2 GAMBIT: MODELLINGThe pre-processing of the A-Pillar was again performed using Gambit. For the purposes of this study, a model representing half of the whole Range Rover car geometry was provided. However this model did not feature the wing mirror and therefore the wing mirror geometry was imported into the model and attached to the car body through stitching the lower topology of the volumes together. Similar to the flat plate model, a brick volume was then created around the car geometry, with the dimensions of 10x4x4m and the volumes were aligned with brick volume wall. The car and wing mirror volume were then subtracted from the brick volum, thus creating the flow domain. Extensive geometry cleaning measures had to then be taken due to complexity of the car geometry; this was performed with the use of the automatic geometry clean up tools and through manual manipulation of the model. Multiple face merging operations were carried out and the effects of these processes are illustrated in Figure 20 which shows certain areas on the car and wing mirror surfaces smoothed over (door handles, trim, headlights etc.). 
Figure 20 - Simplified Car Geometry This reduction in geometry complexity was essential due to the limited processing power available and thus the limited meshing and solving capabilities. Too fine a mesh would prove difficult to apply to such a large and complex model; furthermore, the capability of the available processing power would fall short of solving the resultant flow simulation. Download 3.93 Mb. Share with your friends:
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