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I think I may not have passed along the idea of the inverse rule quite right.
Essentially the quick and dirty way to discover what a solid will encounter in a moving solution, is to assume that the solid is actually the piping for a fluid. Once you decided where the high pressures would be located inside the pipe you can assume the opposite(if its high on the pipe model that particular outside surface experiences low pressure in the fluid).
So if you take say a conical tail fin and we want to know what the relative pressures are on the outside walls we could look at a nozzle in a pipe. The nozzle accelerates the flow by restricting the flow and the pressure forces the fluid to travel faster out of the nozzle.
In that diagram the sloped walls of the nozzle experience relatively high pressure and therefore if instead the nozzle is the tail piece for a jet traveling through a fluid the exterior walls are faced with a relatively low pressure by the rule of thumb.
so in this example its like a half nozzle in the original pressure contour or a full nozzle in others with a pressure release point in the wall(I think someone said in the middle but I'm not going to say that for sure because its late). So the nozzle with an initially steeper slope will see higher pressures than the conical nozzle(more pressure where the curve begins because its steeper than a straight line cone-nozzle). Around the release points(inversely the suction point) there will be a drop in pressure, it won't approach a low pressure zone but it will be like a teal color rather than navy blue. The reverse image of that is a low pressure surface with a suction point of not-quite-so-low pressure but definitely not neutral or high pressure.
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