Calculation of nonstationary flows of a relaxing gas in ducts

By using a unified numerical scheme, four characteristic stages are identified in the transition process under conditions of periodic energy input to the subsonic part of a jet modeling the flow path of an axisymmetric arc heater and a supersonic nozzle. Pulsed flow in the discharge chamber of an impulsive wind tunnel following the rupture of the diaphragm is shown to be possible. The similarity parameters of such flows are determined by analyzing equations of nonstationary flow for a relaxing gas.