Aerodynamic Investigation Of Flow Characters Of Internal Cooling Channel With Both Rib-roughened Walls And Film Hole Suctions

To satisfy the practical need of internal cooling in turbine blades of aeroengine, some detailed experimental measurements on the discharge coefficients, pressure coefficients and flow field in the internal passages with both rib-roughened walls and film hole suctions under a wide range of aerodynamic parameters. And the interrelated numerical simulation was also been implemented.The measurements of discharge coefficients and pressure coefficients along the models with aspect ratios of 0.5, 1.0 and 2.0 were carried out under various aerodynamic and geometric parameters(Reynolds numbers: 20000, 40000, 60000, 80000; Suction rates: 0.3,0.45 and 0.6; Rib angles: 45° ,60° ,90°, 120° ;Rib height -to-width ratio h/e: 1.0 and 2.0; Film Hole location: Middle of ribs. Upstream of ribs and downstream of ribs). Based on the abundant experimental data and figures, rules of discharge coefficients and pressure coefficients in dependence of geometric and aerodynamic parameters were given out. It is found in the experiments that film hole Reynolds number and Rib angle have great influence on film hole discharge coefficients. Film hole discharge coefficients at first increase with the increase of film hole Reynolds number and then keep almost constant when film hole Reynolds number exceeds 15000. The ribs create secondary flow which change direction of flow entering film holes, thus influence the discharge coefficients. Increasing suction rate or flow Reynolds number can increase pressure coefficients, but the existence of ribs lead to decrease of pressure coefficients. The higher the ribs, the lower the pressure coefficients.In this thesis commercial software FLUENT5 was used to implement numerical simulation because it could in more detail and comprehensive display the distribution of the flow field in the channel and in the holes and the experimental results could be consummately enlarged. At last, the experimental results were contrasted and analyzed with the numerical ones...