Development of measuring systems of dissociated oxygen in hypersonic tunnel flows

高超音速风洞流可以提供数据库，支持整个日本太空项目，包括希望- x和即将命名的航天飞机项目。特别是为了解决再入空间飞行器的热屏蔽问题，必须对现有的激波管进行升级，以满足这些极端条件的产生。本研究的目的是开发设备和测量系统。结果总结如下：(1)将100 mm × 180 mm激波管的高压室改造为爆轰驱动操作系统，并采用快开阀，保证了较高的重复性。通过数值和实验对其特性进行了澄清。(2)对爆震波起爆进行了实验研究。为了阐明在初始压力为10 - 100千帕的氢氧米联中从爆燃驱动激波到爆轰的转变，在爆轰室中激光点燃了重量为1.0 - 10毫克的微装药。通过全息干涉观测，确定了起始边界。(3)对二维和轴对称喷嘴的启动过程进行了数值和实验研究。在轴对称喷嘴的情况下，构造了一个非球面透镜形状的会聚发散喷嘴，使准直物束能够通过，而不会造成测试截面图像的畸变，从而实现了图像数据的定量采集。(4)对于实验结果的解释，提出了一种采用非结构网格的dinette差分格式，并获得了更高的分辨率。

Hypersonic wind tunnel flows can provide data base which would support entire Japanese space projects including HOPE-X and forth coming named space shuttle projects. In particular, to resolve heat shielding of re-entry space vehicles, the existing shock tube has to be upgraded to satisfy the generation of these extreme conditions.The aim of the present study is to develop the facility and measuring systems. Results obtained are summarized as following :(1) The high pressure chamber of a 100 mm x 180 mm shock tube has been modified to detonation driving operation systems and a quickly opening valve has been adopted to ensure higher degree of repeatability. Its characteristics are numerically and experimentally clarified.(2) The initiation of detonation waves was experimentally examined. A micro-charge ranging from 1.0 to 10 mg in weight was laser ignited in a detonation chamber, in order to clarify the transition from deflagration driven shock waves to detonation, in oxyhydrogen miters at initial pressure from 10 to 100 kPa. By using holographic interferometric observations, the boundary of initiations has been determined.(3)Starting processes in two-dimensional and axisymmetric nozzles have been numerically and experimentally investigated. In the case of an axisymmetric nozzle, an aspheric lens shaped converging and diverging nozzle was constructed and collimated object beam could pass without creating any distortion of images of test section, with which a quantitative image data acquisition became possible.(4) For the interpretation of experimental results, a dinette difference scheme using unstructured grids has been developed and a higher resolution has been obtained.