Measurement and Determination of Local Film Cooling Performance Along a Transonic Turbine Blade Tip With Viscous Dissipation
Measurement and Determination of Local Film Cooling Performance Along a Transonic Turbine Blade Tip With Viscous Dissipation
复制标题
具有粘性耗散的跨音速涡轮叶尖局部气膜冷却性能的测量和确定
DOI：
10.1088/1361-6501/ac543d
复制
发表时间：
2022
影响因子：
2.4
通讯作者：
P. M. Ligrani, H. Collopy
中科院分区：
文献类型：
--
作者：
P. M. Ligrani, H. Collopy
介绍了测量和确定跨音速流环境下沿着涡轮机叶尖气膜冷却性能参数的实验和分析方法，这些方法考虑了粘性耗散的影响。这种粘性耗散的大小是至关重要的，以确定适当的驱动温度，在高速，可压缩的环境中的对流传热。在这个过程中的一个关键步骤是绝热表面温度幅度的分离，由于绝热表面温度值与粘性耗散相关的流动效应的热场。仅根据流动效应确定的这些绝热表面温度值是在没有薄膜冷却的情况下确定的，当相对于流动停滞温度考虑时，薄膜冷却直接与沿沿着叶尖表面的叶尖间隙流动内的局部马赫数值相关。在实施分离之后，仅提供来自膜冷却热效应的绝热表面温度变化相对于没有膜冷却的局部基线值。随后确定所产生的局部绝热膜冷却效率和局部传热系数，其完全基于局部测量的温度（不使用全局温度参数），这是用于呈现空间分辨表面传热特性的最适当的视角。提供了带凹槽边缘和凹槽的叶尖表面的相关数据，有和没有气膜冷却。采用沿二维涡轮机叶片的上压力侧沿着布置的五个薄膜冷却孔的阵列来提供薄膜冷却剂，局部吹风比BR为3.02。叶尖间隙与真实叶展的比值分别为0.66%和1.16%。用于获得空间分辨表面数据的实验程序包括红外热成像、瞬态测试技术和用于瞬态数据分析的脉冲响应方法。
Presented are experimental and analytic procedures for the measurement and determination of film cooling performance parameters for a transonic flow environment along a turbine blade tip, which account for the influences of viscous dissipation. Such viscous dissipation magnitudes are vital to ascertain appropriate driving temperatures for convective heat transfer within high velocity, compressible environments. A key step in this procedure is the separation of adiabatic surface temperature magnitudes due to the thermal field from adiabatic surface temperature values associated with flow effects related to viscous dissipation. These latter adiabatic surface temperature magnitudes, from flow effects only, are determined with no film cooling, which, when considered relative to flow stagnation temperature, are directly related to local Mach number values within the tip gap flow along the blade tip surface. After the separation is implemented, adiabatic surface temperature variations from film cooling thermal effects only are provided relative to local baseline values with no film cooling. Resulting local adiabatic film cooling effectiveness and local heat transfer coefficients are subsequently determined which are based entirely upon locally measured temperatures (without the use of global temperature parameters), which is the most appropriate perspective for presentation of spatially-resolved surface heat transfer characteristics. Associated data are provided for the surface of a blade tip with a squealer rim and recess, with and without film cooling. An array of five film cooling holes, located along the upper pressure side of a two-dimensional turbine blade, are employed to provide the film coolant, with a local blowing ratio BR of 3.02. Ratios of tip gap to true blade span are 0.66%, and 1.16%. Experimental procedures employed to obtain the spatially-resolved surface data include infrared thermography, transient testing techniques, and the impulse response method for transient data analysis.