Session: ASME Undergraduate Student Design Expo

Paper Number: 166332

Development of a 5,000lbf Kerosene-Liquid Oxygen Open Cycle Turbopump 

A team of undergraduates, comprised mostly of first-years, was assembled with the objective to design, build, and test a rocket engine turbopump within the span of approximately one academic year, with a long-term goal of a full-stack hotfire within approximately two. Understandably an ambitious target, guidance was provided by a cadre of older team members, with a stronger background in project management built from prior experience with engineering teams. The overall system architecture was authoritatively decided at the beginning of the project: an open-cycle, single-shaft arrangement sized for a blackbox 5000 lbf thrust chamber assembly would be utilized, building upon substantial prior art, given the ubiquity of gas-generator cycles during the Apollo program, as well as continued work on low-cost, high-reliability kerosene-oxygen engines by the FASTRAC and Merlin engine programs. A conservative, mature architecture would thus be utilized to minimize technical risk, in addition to a design paradigm further emphasizing ease of integration, low cost, and fast development time, even at the expense of performance. 

 

Successful development of this system would serve to train a cohort of highly accelerated engineering students by exposing them to work rarely accomplished by mere undergraduates. A rigorous technical onboarding procedure was applied, wherein a generic literature review on the state of the art of rocket turbopumps, making heavy use of the NASA Technical Reports Server (NTRS), was first required of all members. Upon completion of this review, subteams were delineated based on student interests, one each for pumps, rotordynamics and seals, turbine, and gas generator. Subteams were then required to conduct a literature review upon their respective subsystems, again leveraging the NTRS delivering presentations that leveraged the “explain like I’m five” teaching paradigm: students were tasked with digesting the underlying physics and engineering of their component subsystems, then presenting those principals to the other subteams in fundamental and plain language, thus ensuring that each member had fully understood the technical content of their own tasks. 

Thus with the cohort indoctrinated, external design tools were leveraged to accelerate and derisk development schedules. Commercial and public access codes and softwares were leveraged, namely Dyrobes for rotordynamic analysis, CFTurbo for pump design, and NASA CEA for gas generator design. Additionally, a strong, system-level technical leadership structure was applied, wherein inputs from each team were communicated and iterated into a “master sketch”, a literal, hand-drafted sketch of the entire turbopump system, which allowed immediate definition of packaging requirements and general arrangements. Both additive and subtractive manufacturing processes are utilized, and requisite design for manufacture is discussed. As of February of 2025, the system is in the critical design phase, and plans and procedures for manufacturing and quality assurance, as well as buildup of test and auxiliary infrastructure are currently being matured, with the goal of integrated turbopump operation under gas-generator power planned by the end of Spring 2025.

Presenting Author: Kamon Blong Purdue University

Presenting Author Biography: Kamon Blong is a founding member and co-president of the Purdue Undergraduate Rocket Propulsion Lab (PURPL), an extracurricular club dedicated to giving undergraduates practical, hands-on experience with design, build, and test of jet propulsion technologies by hosting a multitude of air breathing, rocket, and electric propulsion design teams. He is also co-manager of the turbopump project, and outside of school and PURPL, has been involved in Air Force sponsored research and development of rotating detonation rocket engines.

Authors:

Kamon Blong Purdue University
Forrest Lim Purdue University