权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Study of Non-Equilibrium Condensation in a Supersonic Jet

超音速射流非平衡凝结研究

基本信息

批准号：
60550040
负责人：
TESHIMA Koji
金额：
$ 1.15万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1985
资助国家：
日本
起止时间：
1985 至 1986
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-60550040/
关键词：
Condensation Gasdynamics Supersonic Freejet Numerical Fluid Dynamics Thermodynamics レーリー散乱

项目摘要

1. Experimental studies of argon freejets with condensation.1) Freejet flow-fields were visualized utilizing laser Rayleigh scattering from condensates. From analysis of the visualized jets influences of condensation on the jet structure were examined; the Mach disk moves downstream and the barrel shock expands as a result of condensation. Stronger scattering was observed in a region between the barrel shock and the jet boundary than in the jet core.2) Strength of the Rayleigh scattering was measured along the jet axis. Changes of an average number of atoms in a cluster, J, were obtained from the measured intensity using numerical results of the condensation mass ratio. The value of J reaches 100 - 6000 depending on the stagnation condition. These values agree with those measured by a more direct method in a cluster beam.2. Numerical simulation of a freejet with non-equilibrium condensation.1) A method of numerical simulation of a freejet with condensation was established. For the condensation the classical nucleation theory was used.2) The method was extended to a case of a stochastic nucleation process. Numerical results show that the macroscopic flow properties are almost independent of unkown properties concerning with small clusters, but microscopic ones like values of J depends strongly on these values. By comparing parametric studies using this numerical method with experimental observation these parameters can be determined and hence the non-equilibrium condensation processe in a supersonic jet will become more clear.

1.冷凝自由射流的实验研究1)利用激光瑞利散射技术对冷凝液中的自由射流流场进行可视化。通过对可视化射流的分析，研究了凝结对射流结构的影响；凝结导致马赫盘向下游移动，筒体激波扩展。在炮管激波和喷流边界之间的区域内观察到了比喷流核心更强的散射。2)沿喷流轴测量瑞利散射强度。利用凝聚质量比的数值结果，从测量的强度得到了团簇中平均原子数J的变化。根据停滞状态的不同，J值可达100-6000。这些值与在集群光束中用更直接的方法测量的值一致。非平衡冷凝自由射流的数值模拟1)建立了冷凝自由射流的数值模拟方法。对于凝结，采用经典成核理论。2)将该方法推广到随机成核过程。数值结果表明，宏观流动性质几乎与小团簇的未知性质无关，而微观性质，如J值，则强烈依赖于这些值。通过将用这种数值方法进行的参数研究与实验观测相比较，可以确定这些参数，从而使超音速射流中的非平衡凝结过程变得更加清楚。