Abstract—

Local flow swirling is used in power facilities and other technical devices. It is an effective means for acting on the air flow structure and can enhance heat transfer. A swirled flow in axisymmetric channels belongs to the group of 3D flows in the field of centrifugal mass forces. It is characterized by the ratio of two (axial and rotational) or, in some cases, three components of the velocity, the presence of transverse and longitudinal pressure gradients, and high turbulent fluctuations that bring about certain difficulties in the investigation of processes occurring in a swirled flow and it complicates detection of their regularities. Therefore, it is proposed to install a vortex chamber (VC) at the leading edge of a blade or vane of a high-temperature gas turbine. Temperature conditions and flow capacity of VC models were studied by a calorimetric method in a liquid-metal thermostat. The regularities of heat transfer rate on the surface of the cooling channels were determined depending on the number and diameter of inlet (supply) and outlet holes for various pressure drops. The VK designs were optimized considering the effect of their geometry on the formation of various swirl flow structures with different levels of heat transfer enhancement. An analysis was performed with account taken of the throughput capacity of the models. The criterial dependences of the Nusselt number vs. Reynolds number Re were obtained for three VC designs for direct- or reverse-flow direction. The highest heat fluxes were observed on the section of coolant supply via holes, which is explained by a high velocity of the initial flow swirling. Flow swirl breakage and cooling air heating are the cause of a decrease in the relative heat transfer coefficient \({\bar {\alpha }}{\text{.}}\) The self-similarity mode is observed at a pressure ratio across the vortex chamber above 1.4. The thermal problem was solved using data of the hydraulic tests of the models with air blowing under isothermal conditions. The results of experimental studies can be included in the data bank of heat and mass transfer software products to reduce the labor intensity and time in the development of a cooling system for blades/vanes of high-temperature gas turbines.

中文翻译：

---

涡流室的热工水力特性研究

摘要—

电力设备和其他技术设备中使用局部流动涡流。它是作用于气流结构的有效手段，可以增强热传递。轴对称通道中的旋流属于离心质量力领域中的3D流。它的特征是速度的两个（轴向和旋转）比值，或者在某些情况下是三个分量的比值，横向和纵向压力梯度的存在以及湍流的剧烈波动，这给研究过程中的过程带来了一定的困难。旋流，使规则规律的检测变得复杂。因此，提出在高温燃气轮机的叶片或叶片的前缘安装涡流室（VC）。通过量热法在液态金属恒温器中研究了VC模型的温度条件和流量。冷却通道表面的传热率规律取决于各种压降的入口（供应）和出口孔的数量和直径。对VK设计进行了优化，考虑了其几何形状对具有不同水平的传热增强作用的各种旋流结构的形成的影响。考虑到模型的吞吐能力进行了分析。对于正向或反向流动方向的三种VC设计，获得了Nusselt数与Reynolds数Re的标准依赖性。在通过孔的冷却液供应部分观察到最高的热通量，这可以通过初始流动的高速旋转来解释。旋流破裂和冷却空气加热是相对传热系数降低的原因\（{\ bar {\ alpha}} {\ text {。}} \\）在跨涡室的压力比高于1.4的情况下观察到自相似模式。使用模型在等温条件下吹气的水力试验数据解决了热问题。实验研究的结果可以包含在传热和传质软件产品的数据库中，以减少开发用于高温燃气轮机叶片/叶片的冷却系统的劳动强度和时间。