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This was the team's first P motor. It was designed to be around a P9000 ? but a currently due to an unknown effect led to had a much shorter burn time and higher than expected thrust. Current theories for the burnrate-increasing effect include erosivity, or more complete aluminum combustion leading to much higher temperatures. The second theory is supported by the slight bulge in the case as well as higher residency time of half of the aluminum particles. After reviewing the BurnSim files used to design the motors, it appears that a software bug may have played a role in the motor's unexpectedly high thrust. BurnSim assumes that the highest mass flux will always be at the bottom grain, but in the case of the P motor's tapered core, it was actually at the end of the grains with the 1.72" cores. This almost certainly led to significant erosivity at this point and was probably responsible for the motor's high burn rate. More details can be found here.

Media

Link to Dropbox: here

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