Analogue for High-Intensity Steady-Flow Combustion Phenomena

In this paper a technique is described which is intended to assist in the preliminary stages of developing a high-intensity combustion chamber for an aircraft gas-turbine or ram-jet. Since the chief unknowns are aerodynamic rather than chemical, an air-flow model is made; the chemical reaction is then simulated by electric heaters distributed through the chamber. External controls regulate the heat input in accordance with the local temperature and the properties of the fuel which is to be simulated.

The apparatus used is a prototype intended to demonstrate the principle rather than to make predictions, but good agreement is found between predicted blow-out velocities of baffle-stabilized flames and experiments on these flames reported by other workers.

Tests are also reported on two-dimensional combustion chamber designs for burning pre-mixed fuel and air, the efficiency, space utilization, and pressure-drop performance being compared. It is shown by an example that separate injection of fuel to the combustion chamber greatly reduces the blow-out velocity and space utilization, but increases the combustion efficiency and the range of fuel-air ratios over which a flame can be maintained.

The analogue does not simulate atomization, heat loss, carbon formation, or gas-dynamic instability.