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Ramjet pod functionality and design

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Alan15578

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This reminds me of a discussion in the early days of altimeter use in in NAR competition, with porly worded rules. I suggested that the altimeter could be ported to a low pressure region of the airframe, producing higher altitude readings than those taken at true apogee. I suggest the altimeter could be ported to the convex corner of a conical transition. To drive home the point, I suggested that altimeter could just be ported to the throat of a venturi. They finally adjusted the rules.

So, my question is, how would you design a venturi into or around a contest rocket to maximize the "altitude" reading of the altimeter?
 

jqavins

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Would that scam work, given that altitude at apogee is near zero? (Actually zero in a dead vertical flight.) The effect should be, if I'm not mistaken, a false appearance of very rapid acceleration as both the outside pressure and the effect of the venturi are increasing, then a slow rise as the real air pressure continues to fall while the venturi effect of fake altitude fades, leading to an accurate apogee.
1611597219972.png
OK, yes, the fake altitude peaks 1.375% higher than the actual altitude in this very, very crude simulation.
 

shockie

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