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Constant entropy sampling and release waves of shock compressions
Jean-Bernard Maillet1, Emeric Bourasseau, Laurent Soulard
1CEA, DAM, DIF, F-91297 Arpajon, France. jean-bernard.maillet@cea.fr
Summary
We present equilibrium methods to compute isentropic processes in shocked liquids. Results show that liquid viscosity and nonequilibrium effects prevent strictly isentropic release, impacting high-pressure material behavior.
Area of Science:
- Thermodynamics
- Fluid Dynamics
- Materials Science
Background:
- Isentropic processes are crucial for understanding material behavior under extreme conditions.
- Previous models often assume equilibrium, which may not hold for dynamic processes like shock release.
Purpose of the Study:
- To present and apply equilibrium methods for calculating isentropic compression and release.
- To compare equilibrium predictions with nonequilibrium simulations for shocked liquids.
- To investigate the factors causing deviations from isentropic release.
Main Methods:
- Development and application of equilibrium computational methods.
- Simulation of isentropic release in a shocked monoatomic liquid.
- Comparison of equilibrium and direct nonequilibrium simulation results.
Main Results:
- Equilibrium methods were successfully applied to compute isentropic processes.
- Nonequilibrium simulations revealed deviations from strictly isentropic release.
- Liquid viscosity and nonequilibrium effects were identified as key factors influencing the release process.
Conclusions:
- The assumption of strictly isentropic release is not always valid for shocked liquids.
- Viscosity and nonequilibrium phenomena play significant roles in dynamic material response.
- Accurate modeling requires consideration of nonequilibrium effects for shocked fluid release.
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