2016 Intercollegiate Rocket Engineering Competition
Our Rocketry team annually competes in the 2016 IREC, held in the desert of Green River, Utah. Our performance placed us 3rd in the Advanced Category out of 10 teams. Despite several drawbacks posed by the high volume of teams and limited launch windows, we were able to launch successfully on the final day. The rocket, Deliverance, was designed to reach an altitude of 23,000 ft with 900 lbs of thrust from a nitrous oxide/paraffin hybrid engine.
Experimental data from static fire testing throughout the year indicated regression rate issues in our fuel core; full combustion was only sustained for about 2 seconds before the paraffin wax was depleted, instead of the designed 5 seconds. Additionally, our load cell data suggested that our maximum thrust was only about 60% as expected, although recent inspection of the load cell indicates that its measurements may not be accurate. However, based on our knowledge at the time, we arrived at the competition with a revised altitude estimate of ~10,000 ft, expecting a 2-3 second burn at around 450 lbs of thrust.
Due the complications in scheduling management at the competition, our launch was enormously delayed. While we had prepped the rocket to fly by 8 AM, we were not able to set up on the launch rail until 11 AM. This meant the rocket was partially exposed to the desert heat for an additional 3 hours, which caused our wax fuel core to soften (The ambient temperature was upwards of 40 degrees Celsius, only about 20 degrees from the melting point of paraffin). As a result, when the engine was ignited, combustion only occurred for a fraction of a second before the high pressure of the nitrous oxide squeezed the rest of the fuel out of the nozzle unburnt. With this minimal amount of thrust, and additional momentum from the oxidizer acting as a cold gas thruster, the rocket only achieved an altitude of 1500 ft. However, despite underperforming, all systems of the rocket were demonstrated to work nominally. The recovery system deployed as designed, although the greatly reduced altitude did not give the main parachute enough time to open completely.
Experimental data from static fire testing throughout the year indicated regression rate issues in our fuel core; full combustion was only sustained for about 2 seconds before the paraffin wax was depleted, instead of the designed 5 seconds. Additionally, our load cell data suggested that our maximum thrust was only about 60% as expected, although recent inspection of the load cell indicates that its measurements may not be accurate. However, based on our knowledge at the time, we arrived at the competition with a revised altitude estimate of ~10,000 ft, expecting a 2-3 second burn at around 450 lbs of thrust.
Due the complications in scheduling management at the competition, our launch was enormously delayed. While we had prepped the rocket to fly by 8 AM, we were not able to set up on the launch rail until 11 AM. This meant the rocket was partially exposed to the desert heat for an additional 3 hours, which caused our wax fuel core to soften (The ambient temperature was upwards of 40 degrees Celsius, only about 20 degrees from the melting point of paraffin). As a result, when the engine was ignited, combustion only occurred for a fraction of a second before the high pressure of the nitrous oxide squeezed the rest of the fuel out of the nozzle unburnt. With this minimal amount of thrust, and additional momentum from the oxidizer acting as a cold gas thruster, the rocket only achieved an altitude of 1500 ft. However, despite underperforming, all systems of the rocket were demonstrated to work nominally. The recovery system deployed as designed, although the greatly reduced altitude did not give the main parachute enough time to open completely.