The effect of main stream flow angle on flame tube film cooling
Abstract
Generally film cooling configurations are positioned such that they are oriented perpendicular to the main stream flow direction. However in many cases, in particular combustor applications, different flow angles may occur. Then, due to the interaction between the main stream and the cooling film, a complex three-dimensional flow field with a vortex is formed. An experimental study was done to study the basic effects. The cooling configuration was a vertical slot which could be turned by up to about 60 degrees from the position perpendicular to the main stream. Velocity distributions were measured and the adiabatic film cooling effectiveness was determined using the liquid crystal technique. The results show that, along lines parallel to the slot, the film cooling effectiveness varies strongly, even with small slot turning angles. This would lead to hot and cold spots in a combustor application. A simple semi-empirical correlation for the average cooling effectiveness is derived using the main stream velocity component perpendicular to the slot.
- Publication:
-
In AGARD
- Pub Date:
- February 1993
- Bibcode:
- 1993htcg.agar.....K
- Keywords:
-
- Combustion Chambers;
- Cooling Systems;
- Film Cooling;
- Flow Distribution;
- Gas Turbine Engines;
- Flow Velocity;
- Slots;
- Three Dimensional Flow;
- Velocity Distribution;
- Vortices;
- Fluid Mechanics and Heat Transfer