Structure of a supersonic gas jet under conditions of developed condensation

The influence of condensation on the supersonic flow sizes

“…Thus, coefficient k in relation (1) remains constant in the absence of condensation or in the absence of its variation, increases with increasing stagnation pressure and decreasing stagnation temperature, and, hence, with increasing cluster size and condensate fraction for both the primary jet and clustered " wake". Thereat, as in the previously described case [6], the increase in coefficient k tends to a certain limit.…”

“…However, beginning from the last midcentury, studies of formation of van der Waals clusters arising during adiabatic gas outflowing from the nozzle [4,5], as well as active practical application of these clusters in various technologies, necessitated defining the clusters effect on the shape and geometric dimensions of supersonic jets. As our studies showed, changes depending on the cluster mean size are observed in longitudinal dimensions of the socalled " barrels" in the form of which supersonic jets expand during outflowing from both sonic and supersonic nozzles into a flooded rarefied space [6]. At the same time, it was found out that under certain conditions a new-type flow coflowing with conventional barrels [7] arise around clustered supersonic jets, i. e., " primary" barrels; the shape of this flow is similar to that of the primary one, but dimensions are significantly larger.…”

Modeling supersonic rarefied jets on experimental cluster at Novosibirsk State University

“…Varying the stagnation parameters in the prechamber of the supersonic nozzle has found that with increasing stagnation pressure, the proportionality factor in the dimensionless expression describing the size of the first barrel of the traditional jet, proposed in [19], increases [20]:…”

“…Visualizing by means of electron beam diagnostics of the argon flow behind supersonic nozzles, performed on the PCM bench [20], an unusual glow was recorded outside the zone of a traditional supersonic jet, which has the shape of a stream of the same spindle shape as the main jet, but much larger. This flow, which was recorded only under conditions of developed condensation with a diffuse lateral hanging shock of the traditional jet, was identified as a consequence of the penetration of large clusters through the lateral hanging shock and the mixing zone of the traditional supersonic jet and was called the "cluster wake".…”

Radiation of argon clustered flow particles outside the exciting electron beam

“…In the course of experiments on the study of argon jets behind supersonic nozzles, it was found that, under conditions of developed condensation, in addition to a typical spindle-shaped jet, a secondary flow ("wake") of large dimensions is also observed (Fig. 1), which has a weakly damped anomalous glow of a different shade (in comparison with traditional jet) behind the excitation region [1]. Further studies [2] suggested that the reason for the "wake" appearance is the formation of large clusters in the flow, which are able to overcome the lateral shock waves and form their own parallel jet, also limited due to collisions with particles of the background medium.…”