Subsonic radiation waves. II. Propagation of two-dimensional waves

Radiation-gasdynamic processes accompanying the propagation of subsonic radiation waves (SRWs) supported by laser radiation in air were analyzed numerically. A two-dimensional formulation of the problem was used to observe the quasisteady-state propagation of laser absorption waves when the rates of mass transfer across their fronts were similar to the rate of mass transfer across the shock wave front. The influence of the air density, the radiation power density, and the radius of the illumination spot on the SRW parameters was studied in the quasisteady-state regime and in the transient equalized-pressure regime. It was shown that thin channels of reduced density may be created by the absorption of high-intensity radiation at the center of an inhomogeneously illuminated radiation spot and this may result in global restructuring of the flow in regions much larger than the channel and, particularly, in regions much larger than the channel core.