Hybrid Rocket Engine (Lite Saber Engine i1)

thingiverse

This is a project to build a hybrid rocket engine for the ultimate goal of launching a rocket in the desert. The plan involves designing a powerful engine and then stacking it multiple times into a nine-engine configuration to create a replica SpaceX Falcon 9 Rocket. The name of this project comes from the first model, which was painted silver and resembled a lightsaber from Star Wars. I will be uploading videos as I progress with this project, and you can find them here: https://www.youtube.com/watch?v=tsifklldMpU&feature=youtu.be Test 1 Results Setup: - Engine: one chamber and injector - Nozzle: version one nozzle - Fuel: propane starter and roofing tar grain - Oxidizer: Nitrous Oxide "whip it's" Hypothesis: I believed that the propane burn would start the combustion of the tar fuel grain, after which we would introduce NOS and cut off the propane to react the fuel grain and oxidizer. Results: The fuel grain never ignited. A flashback occurred due to premature mixing of the oxidizer and fuel before they entered the combustion chamber. However, the concrete nozzle held up well, and the ABS outer body remained cool to the touch. Lessons Learned: - I misunderstood how the oxidizer and fuel should react initially. - It's crucial to inject the fuel and oxidizer separately through different holes in the injector. - NOS is not safer than GOX; it's actually more hazardous. - In future tests, I will only use GOX or gaseous oxygen with the tar fuel grain for ignition and reaction. Test 2 Results Setup: - Engine: one chamber and injector - Nozzle: version one nozzle - Fuel: roofing tar grain then "Shoe Goo" grain - Oxidizer: Gaseous Oxygen (GOX) at 200 psi max from a welding tank Hypothesis: I believed that with my newfound understanding of oxidizers, I could achieve combustion within the combustion chamber without any flashbacks. Results: - The engine ignited perfectly, and the fuel burned quickly. - However, when refueling, I noticed that the compacted bentonite clay combustion chamber had come un-compacted, and the ABS outer wall was soft. Despite this, I reloaded it anyway for the final phase of the test. - When burning wet shoe goo, the burn was extremely bright, but short-lived. - The concrete nozzle failed after the test, with a hole that expanded from 3/16 to 5/16. Lessons Learned: - The combustion chamber should be made of concrete like the nozzle. - The combustion chamber needs to be larger to accommodate more fuel and pressure. - I need a consistent and powerful fuel grain for future tests so I can focus on one variable at a time, such as nozzle shape. Test 3 Status This test has not yet occurred.