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Updated: Jul 13, 2026
10:33
Research and Development of High-performance Explosives
Published on: February 20, 2016
On high explosive launching of projectiles for shock physics experiments
Damian C Swift1, Charles A Forest, David A Clark
1Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA.
The Review of Scientific Instruments
|July 7, 2007
Summary
Simulations of the Forest Flyer explosive launcher show that projectile curvature and tensile damage are influenced by case material and design. Optimizing case impedance and component thickness can improve projectile flatness and reduce damage.
Area of Science:
- Shock Physics
- Continuum Dynamics
- Materials Science
Background:
- The Forest Flyer system is used for launching projectiles in shock physics experiments.
- Understanding the hydrodynamic operation is crucial for accurate projectile performance.
Purpose of the Study:
- To investigate the hydrodynamic operation of the Forest Flyer explosive launching system.
- To identify factors influencing projectile shape, shock heating, and tensile damage.
Main Methods:
- One and two-dimensional continuum dynamics simulations were employed.
- Numerical convergence and insensitivity to material properties were ensured.
Main Results:
- Simulations reproduced projectile speed and rear surface shape.
- Al alloy cases produced slightly curved projectiles with shock heating and potential porosity.
- Lower shock impedance cases (e.g., polymethyl methacrylate) improve flatness.
- High-impedance cases require design based on oblique shock reflection physics.
Conclusions:
- Projectile curvature results from shock reflection; tensile damage arises from Taylor wave interaction.
- Case material, component thickness, and initiation method significantly affect projectile integrity.
- Future experiments should measure projectile porosity to verify simulation predictions.
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