Engine μ
Project Summary
Engine μ is our first foray into bipropellant rocketry, and Davis's first liquid rocket engine. It will serve as a springboard for testing and development of our future, launch ready rocket engine. Engine μ is a Kerosene/LOX engine with a shear-coaxial injector, G-11/FR5 composite ablative, and a graphite nozzle. Getting to a test as soon as possible is a priority with our first engine. Stay tuned for our first hot-fire coming to mojave soon™.
Shear-Coaxial Injection
Engine μ makes use of shear coaxial injectors. Each of the 42 injection elements has a inner diameter of 38 thou from which the LOX flows out of, and a 4 thou annular gap for our Kerosene. This configuration has been shown to achieve high specific impulse by legacy Nasa designs documented in Tn D-126. This report along with Xcor's patent on micro-coaxial injectors inspired our design. We hope to achieve a specific impulse that excedes 250 s by the end of our first hot-firing campaign.
Ablative & Nozzle
We decided to cool our engine via ablative mainly because of its simplicity relative to regenerative cooling. The graphite nozzle was selected in order to avoid large changes to the throat diameter. the wedge shaped seat around the graphite nozzle allows it to freely expand radially and axially in order to avoid excessive thermal stresses which could cause cracks.