Shock-wave structure of supersonic gas flows in a radial nozzle

In the present paper, results of a study of supersonic flows in radial nozzles of various widths, and jet flows discharged into ambient space, are reported. We show that, at fixed nozzle inlet area, depending on the nozzle width, two types of nozzle flow are possible. If the nozzle width is greater than 0.4 mm, the viscous effects for the gas flow in a radial nozzle can be neglected. Provided that the nozzle width is smaller than 0.4 mm, then the effects due to viscosity cannot be neglected. As a result of gas deceleration, in the nozzle there arises a shock wave with the flow behind this wave being a subsonic one.