This summer I worked with Joe Leahy, a propulsion systems analyst at Marshall Space Flight Center. I worked in the Exploration Systems Mission Directorate, which is the organization that designs and builds the hardware that NASA flies into space. Within that group I worked with a team of engineers whose expertise was liquid rocket engines and main propulsion systems. While I was there, most of the engineers in this group were working on either the Space Shuttle Main Engines or the Ares I upper stage propulsion system.
My task for the summer was to create a computer routine which would calculate several rocket combustion properties. This program, given fuel/oxidizer mixing ratio and combustion chamber pressure, would output the combustion temperature, exhaust gas specific heat, exhaust gas molecular weight, and the exhaust gas’ ratio of specific heats (?). This was a challenge because I had to integrate my program into pre-existing software that was developed by my mentor.
Before I completed my project, the analysts in my group had two programs which would find this information. One of these programs was a chemical equilibrium routine, which could give theoretically exact results, but it took too long to run. The other program was a table lookup routine which ran very quickly but gave results with poor accuracy. My program was a hybrid of these two approaches. Using the chemical equilibrium program, I created a set of equations that described each variable we were interested in. My program would then simply select the correct equations to use and directly calculate the answer. The result was a program that ran as fast the table lookup routine and was nearly as accurate as the chemical equilibrium routine.
Overall, I had a great experience at MSFC. My mentor made sure to involve me in all of the branch activities, so I got a good feel for what it’s like working for NASA. The experience also gave me experience working with propulsion systems and helped me decide that I would go to graduate school. This experience totally reinforced my decision to work in the aerospace industry.
~JOE FERRY, UNIVERSITY OF MISSOURI-ROLLA
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