Experimental investigations of the effects of the injection angle and blowing ratio on the leading-edge film cooling of a rotating twisted turbine blade
Autor: | Zhi Tao, Yi-wen Ma, Feng Han, Zhiyu Zhou, Haiwang Li |
---|---|
Rok vydání: | 2018 |
Předmět: |
Fluid Flow and Transfer Processes
Leading edge Materials science Turbine blade Rotor (electric) 020209 energy Mechanical Engineering Reynolds number 02 engineering and technology Mechanics Condensed Matter Physics 01 natural sciences Turbine 010305 fluids & plasmas law.invention Coolant symbols.namesake Liquid crystal law 0103 physical sciences 0202 electrical engineering electronic engineering information engineering symbols Density ratio |
Zdroj: | International Journal of Heat and Mass Transfer. 127:856-869 |
ISSN: | 0017-9310 |
DOI: | 10.1016/j.ijheatmasstransfer.2018.07.133 |
Popis: | Experimental investigations were performed to study the effects of the injection angle of cylindrical holes and the blowing ratio on the leading-edge-region film cooling of a twisted turbine blade under rotating conditions. The experiments were carried out at a test facility with a 1-stage turbine using the thermochromic liquid crystal (TLC) technique. All experiments were performed at a rotating speed of 574 rpm with an average blowing ratio ranging from 0.5 to 2.0. The Reynolds number was fixed at 6.3378 × 104 based on the mainstream velocity of the turbine outlet and the rotor blade chord length. CO2 was used as the coolant to achieve a coolant-to-mainstream density ratio of 1.56. The film-hole injection angles tested were 30°, 45° and 60°. The results show that both the injection angle and the blowing ratio have significant impacts on film cooling effectiveness. For α = 30° and α = 45°, the radial average film cooling effectiveness increases as the blowing ratio increases in all regions. For α = 60°, this effectiveness first increases and then decreases as the blowing ratio increases, with the case of M = 1.5 yielding the best average cooling performance. At each blowing ratio, the α = 30° case always yields the highest streamwise average film cooling effectiveness in the region of −4.3 |
Databáze: | OpenAIRE |
Externí odkaz: |