Gas dynamics of a rocket plume in the upper atmosphere

An expansion of a rocket exhaust plume in the direction perpendicular to the rocket motion is studied. A comparison is made of the numerical calculations with a self-similar approximation for a strong cylindrically symmetric explosion. It is shown that if a rocket velocity, V-infinity, is high enough and exceeds the sum of an exhaust gas velocity, Ve and a sound velocity, Vs, ( V-infinity > Ve+ Vs), there might be formed, for a short time, a gas-dynamic hole around a rocket flight trajectory in the upper atmosphere where the plume gas concentration is less than the ambient gas concentration at a given altitude. The density and temperature profiles of the transversal plume expansion are calculated, and a possibility of acceleration of the condensed species is discussed.