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OR sim results weirdness, have you seen anything similar?

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afadeev

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I am running sims in OpenRocket v15.03 of my RW Formula 38 built, and two results are weird.
Perhaps someone can point me towards an explanation or can confirm that they are seeing similar aberrations:

1). No matter what size parachute I simulate, the ground hit velocity is always sim-ed as crazy fast, way north of 100mph. Even with 36+" chute on a ~400g/1.0 lb rocket (w/o motor), I get at least estimated 130 mph ground hit velocity. This is silly fast. As a reality check, I loaded the sim for my PML Bumble Bee, and OR sims landing speeds north of 100mph on 48" chute, even though the rockets safely glides down in sub 30 mph speeds in real life. Is this a common/known OR bug, or am I missing something?

2). All altitudes and max velocities for H-motors are super high. When I go from 161 Ns total impulse G-motor (G54) to same 161 Ns H-motor (H165), the altitude results go up by 3x, and simulates speed results by 2x. Basically, I can't trust OR sim results for H+ motors ?!?

My .rkt file:
View attachment FORMULA 38.rkt
My .ork file:
View attachment FORMULA 38.ork

TIA,
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SpaceManMat

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You're launching your rocket above 100,000 ft.

Try changing your launch conditions, the atmospheric pressure should be more like 1013mbar not 3. If in doubt use the standard atmosphere setting.
 

afadeev

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You're launching your rocket above 100,000 ft.

Try changing your launch conditions, the atmospheric pressure should be more like 1013mbar not 3. If in doubt use the standard atmosphere setting.
Got it, thank you!

Interesting that I had launch altitude set at 300 ft, but the mbar value 3 (no idea where that came from) was over-writing that. Somehow, that was particularly effecting H-motor sims (same mbar value was erroneously present G's and F's). I reset mbar to 1013, and all sims produce reasonable outputs.


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