Do 'pontoon' style side skirts offset their frontal area ?
 

Do 'pontoon' style side skirts offset their frontal area in a side wind ?

I added something similar to what Basjoos has on his car to mine ( the irony is that we have the exact same car ) several years ago, but wasn't convinced that they were helping my car due to sidewinds, so i removed them.

Besides city driving, the few trips that i was making were mainly on a stretch of highway that almost always had crosswinds.

At what point does the reduction in drag offset the frontal area in a crosswind ?

( Basjoos did a fine job with his pontoons, and i love the look of them ( aerodynamically that is ) :thumbup:

http://farm4.static.flickr.com/3272/...dd3f352e75.jpg

offset
 

I'm not really qualified to give a quantitative answer,but here's what strikes me.
*To optimize the performance of the aft-body mods something must be done to ensure the clean onset flow which Hucho discusses in his chapter on numerical analysis.
*As we've discussed with the cambered roof as Don Burr has done with semi-trailers,if the overall drag is reduced in spite of the frontal area increase,then its a gain.
*If you look at basjoos' AeroCivic,the bulging of the spats and skirts are in a body location where they would improve sectional density/area rule/Coke-bottling/Whitcomb-waisting,actually reducing pressure spikes as the body is growing or shrinking,and the airflow is being deformed or de-deformed,which is exactly what the air likes.
*In the windward side of a crosswind,the air would be forced to transit these areas directly,guided by the panel;whereas without the 'pontoons' it could 'penetrate' into the wells,reeking havoc on the flow,with premature separation.
*If anyone is going for really low drag,as AeroCivic certainly qualifies,then their almost compelled to do as basjoos.
*Certainly,there's a 'size' at which benefits cancel out locally,but they may still pay dividends downstream,allowing the boat-tailing to do it's nasty.