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Updated: Jun 25, 2026
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Blast Quantification Using Hopkinson Pressure Bars
Published on: July 5, 2016
Shock formation and the ideal shape of ramp compression waves
Damian C Swift1, Richard G Kraus, Eric N Loomis
1Condensed Matter and Materials Division,Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94551, USA. dswift@llnl.gov
Summary
This study provides formulas for shock formation during dynamic compression, optimizing ramp loading for materials like metals and plastics. Simulations confirm these algebraic forms, aiding laser-loading experiments.
Area of Science:
- Physics
- Materials Science
- Computational Science
Background:
- Understanding shock wave formation is crucial for dynamic compression studies.
- Predicting shock behavior in materials under rapid loading is complex.
Purpose of the Study:
- To derive expressions for shock formation based on flow characteristics during dynamic compression.
- To determine the ideal nonlinear shape for ramp loading histories.
- To analyze the effects of lateral release on shock formation.
Main Methods:
- Derivation of algebraic expressions for shock formation.
- Calculation of ramp adiabat using equations of state.
- Comparison with continuum dynamics (hydrocode) simulations.
- Application to laser-loading experiments.
Main Results:
- Expressions for shock formation linked to local curvature of flow characteristics.
- Determination of ideal nonlinear ramp loading shapes.
- Compact representation of regions affected by lateral release.
- Good agreement between derived algebraic forms and hydrocode simulations.
Conclusions:
- The derived expressions accurately predict shock formation and behavior.
- The findings are applicable to various materials, including metals and plastic ablators.
- This work aids in designing and interpreting laser-loading experiments by identifying optimal conditions for shock formation.
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