RESEARCH ON EXTREMELY NONEQUILIBRIUM REACTIVE FLOWS

在高空超高速飞行器的绕流场中，由于飞行器的高速度和低密度，不可避免地会出现热化学非平衡区。针对这种非平衡状态与高速流动之间的相互作用，对非平衡等离子体流动、强激波、超声速燃烧流动、气动激光和低密度流动进行了数值和实验研究.定量地估计了分子离解和复合反应中分子振动能、转动能和自由电子能的变化。数值研究了能量变化和壁面催化对再入体激波层的影响。对电弧加热空气和氩气等离子体的膨胀流动进行了数值研究，发现空气分子的振动温度分布存在显著差异.高时间-波长分辨率的光谱测量方法 ...更多信息 n是为强冲击波建立的。通过对空气冲击波的详细测量，首次发现了分子发射随时间的异常振动变化。发现在强激波反射现象中，必须考虑化学非平衡效应。完成了激波管实验的多点同时测量技术.提出了一种适用于具有快速链式反应和复杂边界条件的超声速燃烧流场的高效数值计算方法。阐明了超音速剪切流场中氢/氧/甲烷的点火特性和反应机理，以及影响激波起爆爆轰稳定性的因素.从实验上发现了风洞型激光器的连续高重复运转特性。对超声速碘激光器、带热交换器的气动激光器和苯燃烧CO_2激光器的特性和性能进行了实验研究。从数值上消除了气体膨胀引起的蒸汽凝结对碘激光器的影响.分析了沿着催化壁和反应壁的努森层，讨论了漫反射壁边界条件的有效性。将DSMC数值方法应用于稀薄超声速射流，验证了DSMC方法的有效性。对低密度超声速射流的结构、稳定性以及稀薄对射流的影响进行了数值和实验研究。少

In flow fields around a vehicleat hypervelocity at a high altitude, thermochemical nonequilibrium regions will inevitably occured owing to its high velocity and low density. Focusing on an interaction between such nonequilibrium states and high velocity flows, numerical and experimental researches were performed co-operatively on nonequilibrium plasma flows, strong shock waves, supersonic combustion flows, gasdynamic lasers, and low density flows.1. The variations of molecular vibrational and rotational, and free electron energies bimolecular dissociation and recombination reactions were eatimated quantitatively. The effects of the energy variations and wall catalysis upon shock layrs of a reenty body was investigated numerically. Expansion flows of arc heated air and argon plasmas were investigated numerically, and remarkably different distributions of vibrational temperature for air molecules were found.2. The method of spectroscopic measurements with a high time-wavelength resolutio … More n was established for strong shock waves. From detailed measurements of air shock waves, abnormal vibratory variations of molecular emission with time were detected for the first time. It was found that in strong shock wave reflection phenomena, chemical nonequilibrium effects must be included. Technique of simulutaneous many point measurements was completed for shock tube experiments.3. An efficient numerical method for supersonic and hypersonic flows was proposed, whick could be applied to supersonic combustion flows with fast chain reactions and complex boundaries. The characteristics of an ignition and reaction mechanisms of hydrogen/oxygen/methane in supersonic shear flows, and the factors affecting the stability of detonation initiated by a shock wave were clarified.4. The continuous and highly repetition operation characteristics of wind tunnel-type laser was found experimentally. The characteristics and performance were investigated for supersonic iodine laser, gasdynamic laser with heat exchangers, and benzene combustion CO_2 laser, experimentally. The effect of vapor condensation by gas expansion on the iodine laser was cleared up numerically.5. Knudsen layr developed along catalytic and reactive walls was analyzed and the validity of diffusion reflection wall boundry conditions was discussed. The DSMC numerical method was applied to rarefied supersonic jets, and its capability was confirmed. Structure of low density supersonic jets, its stability and the effect of rarefaction on it were solved numerically and experimentally. Less