TITLE:
Performance of Gas Turbine Film Cooling with Backward Injection
AUTHORS:
X. C. Li, G. Subbuswamy, J. Zhou
KEYWORDS:
Film Cooling; Cooling Effectiveness; Backward Injection
JOURNAL NAME:
Energy and Power Engineering,
Vol.5 No.4B,
October
14,
2013
ABSTRACT: Gas turbines have been widely used in power generation and aircraft propulsion. To improve the gas turbine performance, the turbine inlet temperature is usually elevated higher than the metal melting point. Therefore, cooling of gas turbines becomes very critical for engines’ safety and lifetime. One of the effective methods is film cooling, in which the coolant air from the discrete holes blankets the surface from the hot gas flow. The major issues related to film cooling are its poor coverage, aerodynamic loss, and increase of heat transfer coefficient due to strong flow mixing. To improve the cooling performance, this paper examined film cooling with backward injection. It is observed that film cooling with backward injection can produce much more uniform cooling coverage under different conditions, which include cases on flat surface with low or high pressure and temperature. The backward injection also performs better in the presence of blade curvature. The effect of other parameters on the film cooling is also reported. The numerical results are validated by simple experimental test in this study.