| Summary: | 碩士 === 國防大學中正理工學院 === 兵器系統工程研究所 === 89 === The present study is aimed to study the film-cooling effectiveness problem by employing the computational fluid dynamic（CFD）technique. The computational simulation has been performed using four kind of commercial software packages, the grid generator, ICEM/CFD, the solver, CFX4.3, and the flowfield visualible /analysis tools, TECPLOT and FIELDVIEW.
There are four different structure multiblock grid systems that are generated to simulate the complicated, three-dimensional turbine flowfield. These grids differ mainly in the cooling hole shape and location, especially in the regions of leading edge and trailing edge. In additional to the grid systems, this thesis also studied the effect of two various coolant-to- freestream blowing ratios, 0.8 and 1.2.
For the given parameters, the coolant geometry parameter has great influence than the blowing ratio on the distribution of adiabatic cooling- effectiveness. Result on the pressure side, it show just little film-cooling effect near the ejection hole, as the reason of great front pressure gradient. On the suction side, the cooling-effectiveness of the head-shower cooling blade is better than the blade with three rows of slot cooling model. Present study clearly exhibits the effect of secondary flow and the endwall on the film-cooling behavior of turbine blade. The complicate flow structures caused by the interaction of coolant flow and mainstream are also presented.
|
|---|
