LATIS modeling of laser-induced midplane and backplane spallation

The computer code LATIS is used to simulate midplane and backplane spallation resulting from short pulsed laser absorption. A 1D planar geometry is simulated with an exponential laser absorption profile. The laser pulse length is assumed to be much shorter than the sound transit time across the laser absorption length. The boundary conditions are a fixed front plane and free backplane and a free front plane and a fixed midplane. The NBS/NRC equation of state for water is used with a self-consistent yet empirical material strength and failure model. The failure model includes the effects of void nucleation, growth and coalescence. Definite signatures of the nucleation and coalescence thresholds are found in the back surface motion for backplane spallation.