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This paper presents a similarity solution for strong blast waves of variable energy propagating in a dusty gas. It is assumed that the equilibrium-flow condition is maintained and the variable energy input is supplied by a driving piston or surface according to a time-dependent power law. Three cases have been investigated: Case I corresponds to a decelerated piston, Case II to a piston of constant velocity, and Case III to a continuously accelerated piston starting from rest. Except in the case of constant front velocity, the similarity solution is valid for adiabatic flow as long as the effect of the counter-pressure is neglected. The effects of a parameter characterizing the various energy input of the blast wave on the similarity solution have been examined. The computations have been performed for various values of mass concentration of the solid particles and for the ratio of density of solid particles to the constant initial density of gas. Tables and graphs of numerical results are presented and discussed.

A similarity solution has been obtained for a laser-driven strong shock wave propagating in a mixture of gas and small solid particles. It is assumed that the equilibrium-ow condition is maintained and the variable laser energy is completely absorbed at the shock front according to a time-dependent power law. The similarity solution is valid for adiabatic ow as long as the e ect of the counter pressure is neglected. The e ects of a parameter characterising the various energy input of the blast wave on the similarity solution as well as on its limits have been examined. The computations have been performed for various values of mass concentration of the solid particles and for the ratio of density of solid particles to the constant-initial density of gas.

The non-adiabatic ow behind a laser-driven strong shock wave propagating in a mixture of gas and small solid particles is the subject of this paper. A similarity solution which accounts for the in uence of internal heat uxes due to high temperatures achieved at the centre has been obtained. The heat uxes in the blast-wave equations are considered in terms of Fourier's law for conduction and by an expression for thermal radiation of the di usion type. As for adiabatic ow, it is assumed that the equilibrium-ow condition is maintained and that the variable laser energy is completely absorbed at the shock front according to a time-dependent power law. The formulation results in a two-point boundary-value problem. The e ects of a parameter characterising the various energy input of the blast wave on the similarity solution as well as on its limits have been examined. The computations have been performed for various values of mass concentration of the solid particles and for the ratio of density of solid particles to the constant initial density of gas.

The problem of strong shock-wave propagation through a dusty gas is studied as a limiting case of very intensive heat transfer. According to potential law, the variable energy is continuously deposited at the shock front. A self-similar solution is found under isothermal condition of the ow ÿeld. The spherical case is worked out in detail to investigate as to how the blast wave is in uenced by the energy input as well as by the mass concentration of the solid particles in the medium and the ratio of density of the solid particles to the initial density of the medium. The cases of instantaneous energy input and dust-free gas are both included in the numerical results as limiting cases.