Abstract Hypersonic and high-enthalpy wind tunnels and their measurement techniques are the cornerstone of the hypersonic flight era that is a dream for human beings to fly faster, higher and further. The great progress has been achieved during the recent years and their critical technologies are still in an urgent need for further development. There are at least four kinds of hypersonic and high-enthalpy wind tunnels that are widely applied over the world and can be classified according to their operation modes. These wind tunnels are named as air-directly-heated hypersonic wind tunnel, light-gas-heated shock tunnel, free-piston-driven shock tunnel and detonation-driven shock tunnel, respectively. The critical technologies for developing the wind tunnels are introduced in this paper, and their merits and weakness are discussed based on wind tunnel performance evaluation. Measurement techniques especially developed for high-enthalpy flows are a part of the hypersonic wind tunnel technology because the flow is a chemically reacting gas motion and its diagnosis needs specially designed instruments. Three kinds of the measurement techniques considered to be of primary importance are introduced here, including the heat flux sensor, the aerodynamic balance, and optical diagnosis techniques. The techniques are developed usually for conventional wind tunnels, but further improved for hypersonic and high-enthalpy tunnels. The hypersonic ground test facilities have provided us with most of valuable experimental data on high-enthalpy flows and will play a more important role in hypersonic research area in the future. Therefore, several prospects for developing hypersonic and high-enthalpy wind tunnels are presented from our point of view.

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高超音速和高焓风洞关键技术的进展

摘要高超音速和高焓风洞及其测量技术是高音速飞行时代的基石，是人类更快，更高，更远飞行的梦想。近年来已经取得了巨大的进步，仍然迫切需要其关键技术进行进一步的开发。高声速高焓风洞至少有四类在世界范围内得到广泛应用，并可以根据其运行方式进行分类。这些风洞分别被称为空气直接加热的高超音速风洞，轻气加热的冲击风洞，自由活塞驱动的冲击风洞和爆炸驱动的冲击风洞。本文介绍了开发风洞的关键技术，基于风洞性能评估，讨论了它们的优缺点。特别为高焓流开发的测量技术是高超音速风洞技术的一部分，因为该流是化学反应的气体运动，其诊断需要专门设计的仪器。这里介绍了三种最重要的测量技术，包括热通量传感器，空气动力学平衡和光学诊断技术。该技术通常是针对常规风洞开发的，但针对高超音速和高焓的隧道则进一步进行了改进。高超音速地面测试设施为我们提供了有关高焓流的大多数有价值的实验数据，并将在未来的高音速研究领域中发挥更重要的作用。所以，