Thrust Vector Control of an Aerospike Rocket Nozzle OVERVIEW The goal of this project is to analyze the feasibility of using secondary fluid injection (SFI) as a method of thrust vector control (TVC) for aerospike rocket nozzles.
THE PROBLEM The aerospike rocket nozzle presents significant performance benefits over conventional converging-diverging (CD), or bell, nozzles. Despite these advantages, aerospikes are almost never selected for use in industry projects, owing to inherent challenges with their implementation and use in flight. One of these key challenges is controlling the thrust vector to maneuver the rocket. Thrust vector control is usually achieved by gimballing the rocket engines. Gimballing, or mechanically moving the engine and nozzle assembly to point the thrust in a desired direction, becomes structurally inefficient in the case of aerospikes.
PROJECT ADVISOR Prof. William M. Hauser
THE REQUIREMENTS ■ N/A
TEAM MEMBERS
THE SOLUTION
Joshua Bender
The aim of this project is to address this controllability problem by
G. Forrest Dawe IV
proving out thrust vector control via secondary fluid injection as a viable
Jayden Ma Liam Ward
solution. Secondary fluid injection produces asymmetric thrust via the lateral injection of a fluid (gas or liquid) into a portion of the supersonic exhaust. A test stand was built to serve as a testbed for studying smallscale aerospike nozzles in the form of nitrogen cold gas thrusters. Next, an aerospike geometry was calculated and designed using Solidworks CAD software and modeled via computational fluid dynamics (CFD) using the Ansys Fluent software. 3D-printing was selected as the primary manufacturing method for simplicity and rapid iteration.
THE RESULTS The first testing campaign served to establish the test stand functionality and the nozzle’s primary functionality of accelerating exhaust gasses to supersonic velocities, thus these first test articles did not include SFI capability. Having proven the architecture, the second testing campaign proved the functionality of SFI in providing TVC capability. Results from recorded force data showed that a significant lateral thrust to primary thrust fraction was achieved. These results provide evidence that SFI presents a viable solution to the inherent controllability challenge of aerospikes.
SENIOR CAPSTONE PROJECTS
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