Geometrical configuration of full-size air-film cooling of swept blades and grid generation techniques

A relatively detailed description was given of the geometrical generation technology and complicated structured grid generation technique for full-size air-film cooled twisted blades. With respect to the generation of air-film cooling geometrical structures, the principle of development from a base level to complexity and from crudity to refinement should be followed. A detailed cooling configuration division shall be conducted only after the basic cooling parts have been identified. The formation of cooling cavities by cutting into slices is more easily realized than by a direct generation of entities. A detailed division process of a wholly structured grid topological structure in the air-film cooling design was given, and the merits and demerits of structured and non-structured grids for air-film cooling calculation were listed. The division of grids shall follow the procedure of from the bottom to the top and employing a layer-by-layer cutting mode. The grid of the cold air column portion should be generated by using an apex grid block construction method on the basis of cavity division. For bowed and twisted blades, the cooling hole layers at an approximately same blade height should be cut into a same layer to a maximally possible extent so that the grid division lines are not grouped too densely. The portion of low quality grid, resulting from the restriction of geometrical structure, shall occupy a minimum quantity of the grid total amount by adjusting the grid number. The above process does not affect the simulation calculation.