Abstract Stagnation-point heat flux was measured on 7° half-angle circular cones with spherical nose diameters of 5, 10, and 25 mm using infrared thermography in hypersonic flow. All models were machined from polyether ether ketone (PEEK). A nominal freestream Mach number of 6 with varying initial stagnation conditions allowed for testing at length Reynolds numbers based on nose diameter ranging from 5 × 10 4 – 5 × 10 5 . Fay & Riddell’s theory for calculating heat flux at the stagnation point provided a comparison to verify experimental data-reduction methods. Excellent agreement was obtained. Sources of deviation were investigated and best practices for obtaining heat-flux values most similar to theory are presented. Heat flux calculated using a one-dimensional assumption had a mean error of 8.9% from the theoretical expectation. To improve upon this, an implicit, finite-difference approximation was used to solve the axisymmetric heat equation in spherical coordinates, assuming a known surface temperature and isothermal back face. The axisymmetric calculation yielded steady-state heat-flux magnitudes 1–10% greater than the one-dimensional approach, as expected. Correcting for longitudinal heat transfer yielded heat fluxes more nearly proportional to 1 / D , and the mean error decreased to 4.8%.

中文翻译：

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定量红外热成像热通量测量的验证

摘要 在高超声速流动中使用红外热像仪在球鼻直径为 5、10 和 25 毫米的 7° 半角圆锥上测量了驻点热通量。所有模型均由聚醚醚酮 (PEEK) 加工而成。标称自由流马赫数为 6，具有不同的初始停滞条件，允许在基于鼻直径范围为 5 × 10 4 – 5 × 10 5 的雷诺数长度下进行测试。Fay & Riddell 计算停滞点热通量的理论为验证实验数据缩减方法提供了比较。获得了极好的同意。调查了偏差的来源，并提出了获得与理论最相似的热通量值的最佳实践。使用一维假设计算的热通量与理论预期的平均误差为 8.9%。为了改进这一点，假设已知表面温度和等温背面，使用隐式有限差分近似来求解球坐标中的轴对称热方程。正如预期的那样，轴对称计算产生的稳态热通量比一维方法大 1-10%。校正纵向传热产生的热通量更接近于 1 / D ，平均误差降低到 4.8%。