| Popis: |
Numerical simulations have been performed on the film cooling characteristics of counter-inclined film-hole rows, which have advantage in manufacturing relative to the usually used parallel-inclined film-hole row structure, on a turbine vane leading edge model. Two types of counter-inclined film-hole row were studied, including collinear counter-inclined film-hole row and non-collinear counter-inclined film-hole row. The distributions of film cooling effectiveness and heat transfer coefficient were obtained for the blowing ratios of 0.5, 1.0, 1.5 and 2.0. The effect of hole pitch on the film cooling effectiveness and heat transfer coefficient was also studied. The results show that the film cooling performances of counter-inclined film-hole rows are not weakened compared to the traditional parallel-inclined film-hole row structure. Film cooling effectiveness of the non-collinear counter-inclined film-hole row is even a little better than the film cooling effectiveness of the traditional film-hole row and collinear counter-inclined film-hole row in the downstream region near the film-hole row. The film cooling effectiveness of the two counter-inclined film-hole row structures decreases with the increase of blowing ratio, while the heat transfer coefficient increases. The change of inclination structure of film-hole row has very little effect on the heat transfer coefficient in the downstream region, while the increase of hole pitch could influence the values of heat transfer coefficient as well as film cooling effectiveness in a relatively notable way. |
