Hydrodynamics of pulsed supersonic underexpanded jets: Spatiotemporal characteristics

Free underexpanded jets in a quiescent medium: A review

“…The transient behavior of the fluid has not focused attention of many studies, be it theoretical [15] or experimental [16][17][18][19] or numerical [17,18,[20][21][22][23][24][25][26] ones. On the contrary, the steady state of the flow has been largely studied in the past , since it corresponded to the most often encountered situations.…”

A Method for Studying Clusterization Processes in a Free Impulse Jet

“…4. The impulse half-width for monomers decreases slightly with an increase in P 0 at low stagnation pressures owing to specific features of the impulse-flow gas dynamics [30]; beginning with a value of ~40 kPa mm, the half-width increases, thereby correlating with a decrease in the signal intensity for monomers (see Fig. 4), i.e., to the threshold of both the developed condensation and the formation of large clusters.…”

“…The duration of a gas impulse was ~1 ms, which, as is known from [14][15], is sufficient for the formation of quasi-equilibrium parameters in the flow. Measurements were performed at the jet's axis behind the axially symmetrical sonic nozzle with a diameter of the exit cross section d = 0.5-1 mm at specified distances x / d from the nozzle edge.…”

Pulsed Gas Jets for Formation of High-Intensity Cluster Beams

“…Obviously the dynamics of free gas expansion is determined by the ratio of the momentum of the expanding gas to that of the background gas. Depending on stagnation pressure P 0 and residual (background) pressure P b we may distinguish three principal regimes of supersonic pulsed expansion [8]: a) expansion into a region of very low background pressure (expansion into vacuum), b) expansion into a continuous medium (flooded space), c) expansion into a region with reduced background gas pressure (intermediate case).…”