The current article presents conceptual, preliminary and detailed aero-thermal redesign of a typical high pressure turbine nozzle guide vane. Design targets are lower coolant consumption, reduced manufacturing costs and improved durability. These goals are sought by 25% reduction in vane count number and lower number of airfoils per segment. Design challenges such as higher airfoil loading, associate aerodynamic losses and higher thermal loads are discussed. In order to maximize coolant flow reduction and avoid higher aerodynamic losses, airfoil Mach distribution is carefully controlled. There has been an effort to limit design changes so that the proven design features of the original vane are used as much as possible. Accordingly, the same cooling concept is used with minor modifications of the internal structures in order to achieve desired coolant flow and internal heat transfer distribution. Platforms of the new design are quite similar to the original one except for cooling holes and application of thermal barrier coating (TBC). Detailed aerodynamics/heat transfer simulations reveals that the reduced trailing edge (T.E.) blockage and skin friction dominated the negative effect of increased secondary losses. As a result the reduced design performs acceptable in terms of total pressure loss and improving stage efficiency for a wide range of varying pressure ratio. Moreover, more than 20% cooling mass flow can be saved; while maximum and average metal temperatures as well as cross sectional temperature gradients have not been changed much.

本文介绍了典型的高压涡轮喷嘴导向叶片的概念，初步和详细的空气热设计。设计目标是降低冷却液消耗量，降低制造成本并提高耐用性。通过减少叶片数量的25％和降低每段翼型的数量来寻求这些目标。讨论了诸如更高的翼型载荷，相关的空气动力学损失和更高的热载荷等设计挑战。为了最大程度地减少冷却剂流量并避免更高的空气动力学损失，必须对翼型马赫分布进行仔细控制。人们一直在努力限制设计变更，以便尽可能多地使用原始叶片的成熟设计特征。因此，使用相同的冷却概念，但对内部结构进行了一些改动，以实现所需的冷却剂流量和内部传热分布。除了冷却孔和热障涂层（TBC）的应用之外，新设计的平台与原始平台非常相似。详细的空气动力学/传热模拟显示，减少的后缘（TE）阻塞和皮肤摩擦力主导了二次损失增加的负面影响。结果，对于大范围的变化的压力比，减小的设计在总压力损失和改善阶段效率方面表现出可接受的。而且，可以节省20％以上的冷却质量流量；最高和平均金属温度以及截面温度梯度变化不大。