SPECIFIC FEATURES OF FORMATION OF SUPERSONIC JETS OF RAREFIED GASES UNDER CONDITIONS OF DEVELOPED CONDENSATION

Abstract

Specific features of gas flows exhausting from supersonic nozzles to a flooded medium under conditions of clusterization are considered. Radiation of particles in the flow is initiated by a well-focused high-voltage electron beam. Radiation is measured by a high-resolution camera and a spectrometer with a wide range of wavelengths. For characteristic sizes of jets of condensing gases in the entire range of examined stagnation pressures and background ambient space, it is possible to use the same dependence on the parameters as that in the case with a correction factor for taking into account the influence of condensation, which, in turn, depends on the cluster size. The form of the correction factor is presented. The dependence of the previously detected process of formation of a secondary external jet in flows of easily condensing gases (“cluster wake") is studied. The reasons and conditions for the emergence of this effect are considered. The processes of formation of the traditional spindle-shaped jet and the new secondary jet are compared. The results of measurements of the diameters of the traditional and secondary jets in the maximum cross sections by means of photometry in various exhaust regimes are reported. The reasons for the differences in formation of the traditional and secondary jets under conditions of developed condensation of particles are considered. The “cluster wake" is found to affect the process of gas penetration from the ambient space to the supersonic flow. Specific features of radiation of the particles of the “cluster wake" are considered, and the time of existence of radiation in the excited state is estimated.