This work presents an approach to the design, and successful experimental validation, of a slug-type calorimeter for long-duration high-enthalpy flows. Specifically, a ceramic shell is used to insulate the slug. Although slug calorimeters have been widely used in arcjets for decades, significant uncertainties are known to be associated with these instruments, which directly affect the uncertainty of critical derived flow quantities such as specific enthalpy. A detailed analysis of the newly proposed design approach is presented. Particular attention has been devoted to the minimization of heat losses from the slug to the shroud, one of the major contributors to the instrument’s uncertainty. The effect of the shroud geometry, insulation thickness, and slug dimensions have been investigated numerically; variable thermophysical properties, nonuniform heat fluxes, and radiation were considered. The analysis showed that the shroud geometry plays a significant role in the heat losses. Based on this design approach, a calorimeter was manufactured to be used in the Office of Naval Research (ONR)–University of Texas at Arlington (UTA) arc-heated wind tunnel “Leste” facility. Experimental measurements in flows with bulk enthalpies up to 4 MJ/kg showed good agreement with the numerical simulations, and measured heat losses were well below the American Society for Testing and Materials standard recommendation.

这项工作提出了一种设计和成功实验验证的方法，用于长持续时间高焓流的段塞式热量计。具体而言，陶瓷外壳用于使嵌件绝缘。尽管数十年来，段塞热量计已广泛用于电弧喷射，但已知这些仪器存在重大不确定性，这直接影响了临界导出流量（例如比焓）的不确定性。对新提出的设计方法进行了详细分析。特别注意最大限度地减少从段塞到护罩的热损失，这是造成仪器不确定性的主要因素之一。已经对护罩几何形状、绝缘厚度和段塞尺寸的影响进行了数值研究；可变的热物理性质，考虑了不均匀的热通量和辐射。分析表明，护罩几何形状在热损失中起着重要作用。基于这种设计方法，制造了一种热量计，用于海军研究办公室 (ONR)-德克萨斯大学阿灵顿 (UTA) 电弧加热风洞“Leste”设施。体积焓高达 4 MJ/kg 的流动实验测量表明与数值模拟非常吻合，并且测得的热损失远低于美国测试和材料协会的标准建议。制造了一个量热仪，用于海军研究办公室 (ONR)-德克萨斯大学阿灵顿 (UTA) 电弧加热风洞“Leste”设施。体积焓高达 4 MJ/kg 的流动实验测量表明与数值模拟非常吻合，并且测得的热损失远低于美国测试和材料协会的标准建议。制造了一个量热仪，用于海军研究办公室 (ONR)-德克萨斯大学阿灵顿 (UTA) 电弧加热风洞“Leste”设施。体积焓高达 4 MJ/kg 的流量的实验测量表明与数值模拟非常吻合，并且测得的热损失远低于美国测试和材料协会的标准建议。