Length to diameter ratio effect on heat transfer performance of simple and compound angle holes in thin-wall airfoil cooling
Length to diameter ratio effect on heat transfer performance of simple and compound angle holes in thin-wall airfoil cooling
复制标题
薄壁翼型冷却长径比对单角孔和复合角孔传热性能的影响
DOI：
10.1016/j.ijheatmasstransfer.2018.08.086
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发表时间：
2018
影响因子：
5.2
通讯作者：
Hongde Jiang
中科院分区：
文献类型：
--
作者：
Weihong Li;Xueying Li;Jing Ren;Hongde Jiang
利用高分辨率热成像液晶技术研究了单角和复合角圆柱孔下游平板表面的换热系数。考察了吹气比等流动参数和复合角、长径比等几何参数的变化规律。吹风比(M) 0.3 ~ 2，长径比（L/D） 0.5 ~ 5，两个复合角（β: 0°，45°）组成70个测试用例的测试矩阵。详细介绍了局部、横向平均和面积平均传热系数hf/h，以说明长径比和复合角的影响。结合绝热膜效率和传热系数数据，采用NHFR法和Δφ法对膜冷却性能进行了评价。结果表明，Δφmethod在评价气膜冷却性能方面具有优势，因为它直接反映了气膜保护的降温效果。
Heat transfer coefficients on a flat plate surface downstream a row of simple and compound angle cylindrical holes are investigated using high-resolution thermographic liquid crystal technique. A variation of flow parameters including blowing ratio, and geometry parameters including compound angle and length-to-diameter ratio are examined. Blowing ratios (M) ranging from 0.3 to 2, length to diameter ratios (L/D) from 0.5 to 5, and two compound angle (β: 0°, 45°) are employed composing a test matrix of 70 test cases. Detailed local, spanwise averaged, and area averaged heat transfer coefficients hf/h0are presented to illustrate the effect of length-to-diameter ratio and compound angle. The film cooling performance is also evaluated using NHFR method and Δφ method by combining adiabatic film effectiveness and heat transfer coefficient data. Results indicate that Δφmethod has superiority in evaluating film cooling performance due to its direct reflection of temperature reduction by film protection.