Analytical and Experimental Evaluation of Aerodynamic Thrust Vectoring on an Aerospike Nozzle

Abstract

Results from numerical and cold-ow experimental investigations of aerodynamic thrust vectoring on a small-scale aerospike thruster are presented. Thrust vectoring was created by the injection of a secondary uid into the primary ow eld normal to the nozzle axis. The experimental aerospike nozzle was truncated at 57% of its full theoretical length. Data derived from cold-ow thrust vectoring tests with carbon dioxide as the working uid are presented. Injection points near the end of the truncated spike produced the highest force amplication factors. Explanations are given for this phenomenon. For secondary injection near the end of the aerospike, side force amplication factors up to approximately 1.4 and side force specic impulses up to approximately 55 s with main ow specic impulses clustering around 38 s were demonstrated. These forces crisply reproduce input pulses with a high degree of delity. The side force levels are approximately 2.7% of the total thrust level at maximum eectiveness. Higher side forces on the order of 4.7% of axial thrust were also achieved at reduced eciency. The side force amplication factors were independent of operating nozzle pressure ratio for the range of chamber pressures used in this test series.

Closed-Loop Thrust and Pressure Profile Throttling of a Nitrous-Oxide HTPB Hybrid Rocket Motor

“…Much of the infrastructure needed to perform throttle testing already existed at USU prior to this study. [31][32][33] New piping and instrumentation were added to the existing test stand to incorporate the throttle control system. All of the other necessary instrumentation and hardware remained unchanged from previous research projects.…”

Side-Force Amplification on an Aerodynamically Thrust-Vectored Aerospike Nozzle

“…The test stand was calibrated in situ with a simultaneously multi-axial calibration method. The total resultant uncertainty (to 95% confidence) for forces using this calibration method was statistically determined as approximately 0.25 N for side forces and 1.75 N for axial loading with nominal values of 15 N and approximately 400 N, respectively [62].…”

Shallow water experiments to verify a numerical analysis on an aerodynamically thrust-vectored aerospike nozzle

“…Aerospike or plug nozzle engines have been developed and tested since the 1950s as an alternative to classical bell nozzles [112]. With their advantageous performance characteristics during the ascent, they have been considered for the upper stage of Saturn V and the Space Shuttle Main Engine [13]. During the 1990s, linear plug nozzle engines were the single-stage-to-orbit propulsion system of choice for the X-33 Mission also known as Venture Star.…”