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Direct modeling of porous materials under shock is a complex issue.We investigate such a system via thenewly developed material-point method.The effects of shock strength and porosity size are the main concerns.For thesame porosity,the effects of mean-void-size are checked.It is found that local turbulence mixing and volume dissipationare two important mechanisms for transformation of kinetic energy to heat.When the porosity is very small,the shockedportion may arrive at a dynamical steady state; the voids in the downstream portion reflect back rarefactive waves andresult in slight oscillations of mean density and pressure; for the same value of porosity,a larger mean-void-size makesa higher mean temperature.When the porosity becomes large,hydrodynamic quantities vary with time during thewhole shock-loading procedure:after the initial stage,the mean density and pressure decrease,but the temperatureincreases with a higher rate.The distributions of local density,pressure,temperature and particle-velocity are generallynon-Gaussian and vary with time.The changing rates depend on the porosity value,mean-void-size and shock strength.The stronger the loaded shock,the stronger the porosity effects.This work provides a supplement to experiments forthe very quick procedures and reveals more fundamental mechanisms in energy and momentum transportation.
Direct modeling of porous materials under shock is a complex issue. We investigate such a system via the newly developed material-point method. The effects of shock strength and porosity size are the main concerns. For thesame porosity, the effects of mean-void-size are checked that I found that local turbulence mixing and volume dissipationare two important mechanisms for transformation of kinetic energy to heat.When the porosity is very small, the shockedportion may arrive at a dynamical steady state; the voids in the downstream portion reflect back rarefactive waves andresult in slight oscillations of mean density and pressure; for the same value of porosity, a larger mean-void-size makesa higher mean temperature.When the porosity becomes large, hydrodynamic stocks vary with time during thewhole shock-loading procedure: after the initial stage, the mean density and pressure decrease, but the temperature increase with a higher rate. the distributions of local density, pressure, temperature and particle-velocity are generallynon-Gaussian and vary with time.The changing rate depend on the porosity value, mean-void-size and shock strength. stronger; loaded shock, the stronger the porosity effects. This work provides a supplement to experiments forthe very quick procedures and reveals more fundamental mechanisms in energy and momentum transportation.