高压涡轮盘腔旋转传热实验台设计及其流动和换热的计算研究

【作者】 卜其龙；

【导师】 冯青；

【作者基本信息】 西北工业大学 ， 工程热物理， 2002， 硕士

【摘要】 在现代航空发动机中，从压气机引出的压缩空气一部分用来冷却涡轮叶片和涡轮导向叶片，另外一部分用来冷却和密封涡轮盘。掌握涡轮盘腔冷却系统内气流的运动规律是对航空发动机高温部件进行冷却的关键。 （1）本文以RRD公司新研制的机种BR700为研究对象，采用κ-ε湍流模型对带有预旋的新型旋转盘腔内的流动进行了数值计算。在旋转盘的计算中提出了一种新的网格剖分方法，计算的旋转雷诺数达到1.0×10⁸。 （2）分析了预旋系数β_r对该旋转盘腔流场的影响，定义了一个新的压力系数C_p，该压力系数C_p沿径向位置的变化对特定的旋转雷诺数Re_θ是一个常数。给出了扭矩系数Cm、平均换热系数Nu_ave随旋转雷诺数变化的关系式，发现它们与没有预旋时是完全不同的，当Re_θ=0时，Cm、Nu_ave不为零，而具有一个初值。 （3）在研究旋转雷诺数Re_θ对该盘腔流动和换热的影响的基础上，进一步研究了流量系数Cw对流动和换热的影响。最后，通过数值模拟预测了在该旋转盘试验中是可以用五孔探针对流场进行测量的。更多还原

【Abstract】 In modern industrial gas turbines and aero-engines, a small percentage of the compressed air is bled off for cooling and sealing purposes. Some of the air is used for cooling the turbine blades and nozzle guide vanes, and part of it is employed to cool and seal the turbine discs. It is crucial for cooling high temperature parts in aero-engines to master the rule of the flow field in turbine discs air cooling system.(1) Taking the new BR 700 gas turbine which is developed by Rolls-Royce Deutshland as research object, the numerical simulation has been applied to the new structure of rotating disk system with pre-swirl nozzles on the rotating disk with к ?ε turbulence model and with a new hybrid grid.( 2) The results reveal that the pre-swirl ratio has a great influence on the flow field of the rotating disk, even greater than the rotational Reynolds number, and an initial constant is induced in moment coefficient Cm and average Nusselt number Nuave correlations, which does not exist in the case of without pre-swirl. A new type of pressure coefficient Cp is defined to lead to a linear correlation with radial locations, which will lead to a curve correlation with radial locations with conventional definition of Cp. The correlations of Cm , Nuave and Cp with rotational Reynolds number have been got through the computation with rotational Reynolds number from zero to 1.0 108.(3) Special attentions are given to flow and heat transfer in the rotating disk cavity which are associated with the rotational Reynolds number , and which the mass flow rate coefficient Cw. Finally measurement of the flow field in the rotating disk with a five-hole probe is demonstrated feasible by the numerical simulation.更多还原