A boundary condition for Guderley’s converging shock problem

Ruby, J. J.; Rygg, J. R.; Gaffney, J. A.; Bachmann, B.; Collins, G. W.

doi:10.1063/1.5130769

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A boundary condition for Guderley’s converging shock problem

Ruby, J. J.·Rygg, J. R.·Gaffney, J. A.·Bachmann, B.·Collins, G. W.

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Abstract

The Guderley model of a self-similar imploding shock based on the group invariance of the flow equations is a powerful tool in understanding the behavior of converging shock waves. Two modifications described here improve the predictions of observable quantities in spherical-shock wave experiments. First, a non-infinite boundary condition is established by the isentropic release of the outer pressure. Second, a two-temperature system of ions and electrons allows description of higher temperatures while conserving energy and without perturbing the overall hydrodynamics of the solution. Furthermore, these modifications of the Guderley model improve the prediction of the observables in laser driven spherical shock experiments in reference to a one dimensional (1-D) hydrodynamics code.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS Newtonian mechanics Thermodynamic properties atomic properties entropy equations of state hydrodynamic codes neutron emission shock wave experiments speed of sound

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Ruby, J. J., Rygg, J. R., Gaffney, J. A., Bachmann, B., Collins, G. W.. 2019-12-16. A boundary condition for Guderley’s converging shock problem. https://doi.org/10.1063/1.5130769

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