The effect of cold air jet injection upon the film cooling effectiveness of combustion chamber walls for different injection geometries
Abstract
A theoretical investigation is undertaken of the influence of cold air jet injection on the effectiveness of combustion chamber wall film cooling, for the cases of several different flow conditions and geometrical parameters. The results of calculation comparisons with experimental data indicate that film cooling effectiveness is improved by higher jet injection velocities and mass flow rates, as well as by smaller distances between two adjacent jets. While larger injection hole diameters decrease cooling effectiveness for the case of constant jet mass flow rate, they increase it for constant injection velocity. These parameters also strongly affect the turbulence level and turbulent heat exhange downstream of the jet injection point. It is noted that oval, rather than round injection holes improve film cooling effectiveness.
- Publication:
-
Heat Transfer 1982, Volume 3
- Pub Date:
- 1982
- Bibcode:
- 1982hetr....3..325B
- Keywords:
-
- Air Jets;
- Combustion Chambers;
- Film Cooling;
- Flow Velocity;
- Fluid Injection;
- Gas Turbine Engines;
- Mass Flow;
- Fluid Mechanics and Heat Transfer