Cooled Liquid Rocket Thrust Chamber

Author(s) Information

Benjamin Gibson, California Polytechnic State University, San Luis ObispoFollow
Kealan Frederick Harris, California Polytechnic State University, San Luis ObispoFollow
Ryan Frank Schackel, California Polytechnic State University, San Luis ObispoFollow
Bjorn Thorsen, California Polytechnic State University, San Luis ObispoFollow

College - Author 1

College of Engineering

Department - Author 1

Mechanical Engineering Department

Degree Name - Author 1

BS in Mechanical Engineering

College - Author 2

College of Engineering

Department - Author 2

Mechanical Engineering Department

Degree - Author 2

BS in Mechanical Engineering

College - Author 3

College of Engineering

Department - Author 3

Mechanical Engineering Department

Degree - Author 3

BS in Mechanical Engineering

College - Author 4

College of Engineering

Department - Author 4

Mechanical Engineering Department

Degree - Author 4

BS in Mechanical Engineering

Date

6-2023

Primary Advisor

Eileen Rossman, College of Engineering, Mechanical Engineering Department

Additional Advisors

Dianne DeTurris, College of Engineering, Aerospace Engineering Department; Björn Kniesner, College of Engineering, Mechanical Engineering Department

Abstract/Summary

Cooling may affect the thrust output of a small-scale rocket. Little research is published about small-scale rocket performance. We hypothesize the thrust produced varies as the amount of cooling varies. To facilitate assessing this hypothesis, we have designed and built a liquid rocket engine rated for at approximately 25 lb_f of thrust. Our objective was to build in parallel with Cal Poly Space Systems, who built a rocket engine with similar specifications except without cooling. Our challenge is to integrate film cooling, so that the effects of cooling may be compared to Cal Poly Space System’s engine which has no cooling. The results will allow for analysis of the effects of cooling on the thrust output of small-scale rocket engines. Utilizing a stacked injector plate design to solve our pressure-drop issues and consequently also solve our mass flowrate issues, we performed more preliminary calculations to justify our decision. We determined suitable material choices with desirable material properties such as the coefficient of thermal expansion and thermal conductivity for our design to be 303 stainless-steel and copper alloy 110. We decided on utilizing copper alloy 110 for our nozzle and combustion chamber, 6061 aluminum for our top injector plate, mild steel for our retaining ring, and 303 stainless-steel for our bottom injector plate. Our finished prototype will be utilized by Cal Poly Space Systems to aid their investigation of the effects of the effects of film cooling on the thrust output of small-scale rocket engines. Hot fire attempts were unsuccessful and resulted in only 15ms of combustion. Recommend more heat to the ignition system to produce self-sustaining combustion to get more effective results in the future.

URL: https://digitalcommons.calpoly.edu/mesp/727