Small-Scale Supersonic Combustion Chamber with a Gas-Dynamic Ignition System

Abstract

The goal of this study was the development of a simple and reliable ignition system for a small-scale supersonic combustion chamber that operates on compressed air and liquid hydrocarbon fuels. As a result, a new combustion chamber operating on a self-ignition principle was developed, in which ignition is accomplished automatically, without electrical equipment or special preparation procedures. A Hartmann–Sprenger tube was incorporated into the combustion chamber, acting as an igniter and as a mixing device. A novel mixing scheme was employed that additionally allows the injection and combustion of tiny portions of fuel inside a resonance tube to increase the temperature of the ignition surface. To increase ignition reliability, the ignition surface was covered with a porous metal jacket, which can also be considered a key technical solution. In the course of the experimental investigations, various aspects of gas-dynamic heating were studied, and the problems of resonance tube and combustion chamber thermal protection were solved. The developed combustion chamber operated stably over a wide range of total mass flow rates and excess air factors. The results obtained here may be useful in the development of other high-temperature gas-jet devices or gas-dynamic ignition systems.

Keywords:

• Combustion chamber
• Compressed air
• Hartmann–Sprenger tube
• Ignition
• Kerosene

ACKNOWLEDGMENT

This work was supported by State Design Office Yuzhnoye of National Space Agency of Ukraine.