Date of Award


Document Type


Degree Name

Master of Science


Department of Aeronautics and Astronautics

First Advisor

Jeffery K. Little, PhD


This thesis investigated the properties of a steam injector to see if the concept might be suitable for use on a liquid rocket engine. A steam injector is a device developed in the 1850's to inject feedwater into the boiler on a steam locomotive without any moving parts. The injectors uses a small portion of the steam generated in the boiler to increase the pressure of the feedwater to a level high than the pressure in the boiler. Previous experiments claim that condensation of steam to water was necessary for an injector to work. This experiment tested injection without condensation using one of AFIT's wind tunnels. Compressed air was used to simulate steam and liquid ethanol was used in place of water. Pressure measurements were taken at points along the tunnel to determine the performance of the tunnel. Results show that this type of injection produces a small pressure rise compared to tests without liquid injection. However, the exit pressure is still lower than the initial pressure. Further testing is recommended to analyze various parameters such as high temperature flows and injector size.

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DTIC Accession Number



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