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reilleya / openMotor

An open-source internal ballistics simulator for rocket motor experimenters
GNU General Public License v3.0
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Comment - Comparing openMotor to Burnsim #96

Closed benrussell11 closed 5 years ago

benrussell11 commented 5 years ago

There is a large difference between the openMotor (OM) and Burnsim(BS) sims for the included files. The OM nozzle parameters were taken from the nozzle.

BS sims to a L1357 and OM to a K720. BS max Pc is 820.ppsi and OM is 549.14. BS total NS=4015 and OM = 2538 ns.

If I "zero out" the nozzle parameters in OM with a nozzle efficiency, the number are close.

OM is using both the efficiency and nozzle parameters for the sim. Right?

I plan on flying this motor next weekend with a Marsa33. I should be able to get a derived thrust curve from acceleration. Should interesting.

75 TT K720.ric.txt 75 TT L1367.bsx.txt

Ben

benrussell11 commented 5 years ago

Never mind ... I had the convergent and divergent half angles wrong.