Numerical solution for spherical laser-driven shock waves

Abstract.

The history of the flow behind a laser-driven shock is investigated in the context of variable energy blast waves. Thereby the total laser energy absorbed by the blast is assumed to vary proportionally to some power of time. Due to the high temperatures and pressures occurring in the initial phase of the flow a real gas model has been employed. It accounts for vibration, dissociation, electronic excitation, ionization and intermolecular forces. Radiative and conductive heat transfer are considered as well. The numerical computations were carried out using the method of characteristics. A self-similar strong shock solution serves as initial condition. It turns out that the exponent which determines the time-dependent addition of energy at the shock front is limited for physical reasons. The computed far-field solutions expand the temporal scope of the self-similar solution domain, which has been the main subject of the classical literature, into the non-self-similar domain at late time. The differences between the solutions obtained for real gas and perfect gas are less significant than in the case of the classical point explosion.