Quote:
Originally Posted by skyking
the low pressure pull over effect of a crosswind is described by Phil here back in 2011.
http://ecomodder.com/forum/showthrea...tml#post276968
Moving or not, the affect is the same. Piling up wind pressure is not the problem, it is the delta-P on the backside.
The skirts are all about drag reduction, improving the flow around the rear tires. |
The sail area matters. As do the winds passing underneath. Slowing enough in speed allows trailer weight to offset that problem. But steady crosswinds of 25-mph with higher gusts are enough to close some Interstates to commercial traffic. WYO DOT used to have a .pdf with calc chart on this (these) effect(s).
It isn't a good idea to consider a trailer as rigid over its length. Any type. Nor any tow vehicle. Winds will twist them. I've watched a 53' van tandems come off the ground at quite an angle. Driver couldn't feel or see it. The rig is turned over from the rear where pressures are greatest.
Where the wind pressure is blocked from passing -- non radiused wall joins -- gives better understanding, IMO, than delineating push from pull.
We're not saying much that is different except by emphasis. BUT low ground clearance is better. And it's not just COG.
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