| Among the advanced internal gas turbine cooling technologies, jet impingement is one of the most effective turbine blade cooling methods, so making researches on impingement cooling shows great significance to people. This study chooses method of numerical simulation to systematically investigate flow field and heat transfer characteristics of array-jet impingement cooling. Following necessary work has been completed during early process of research: Firstly, establish structural grid for study model according to its structural features; Secondly, prove that calculation results is independent of mesh density; Finally, determine the most reasonable turbulence model by comparison with experimental data. The paper also investigates how geometry and flow parameters affect heat transfer efficiency. The results of numerical simulation shows:(1) Compared to the impingement cooling with one side exit, the case of both sides has higher heat transfer efficiency; generated transverse flow will make jet offset from jet-hole, low temperature region ’s shape will change as well.(2) Increasing Reynolds can improve the efficiency of heat transfer, but affects little to flow distribution.(3) Decreasing jet-hole diameter can also improve heat transfer. However, if diameter gets very small, it will increase temperature difference on target surface, which may bring damage to the whole system.(4) Increasing jet-to-jet distance can enhance heat transfer effect as well, but it can not be increased without limit.(5) There is an optimum stand-off distance, making the average heat transfer characteristics achieve best. |
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