We designed and tested multiple grain patterns and converging-diverging nozzle designs to maximize a solid fuel rocket's total impulse. 

From left to right: converging-diverging nozzle, fuel grain CAD/built/tested, our MATLAB-developed model of impulse vs. mixture ratio.

From left to right: converging-diverging nozzle, fuel grain CAD/built/tested, our MATLAB-developed model of impulse vs. mixture ratio.

Myself and a team of four designed and built HDPE (high-density polyethylene) fuel grains and graphite converging-diverging nozzles to maximize total impulse for ME140: Advanced Energy Systems. We used MATLAB to develop a way to model our burn rate as a function of fuel grain geometry, and used it to hold our mixture ratio at the optimal value for the duration of our rocket fire.