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Updated: Apr 15, 2026
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Improving the Combustion Performance of a Hybrid Rocket Engine using a Novel Fuel Grain with a Nested Helical Structure
Published on: January 18, 2021
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Differential ablator-fuel adiabat tuning in indirect-drive implosions
J L Peterson1, L F Berzak Hopkins1, O S Jones1
1Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
Summary
Researchers propose a laser pulse adjustment for inertial confinement fusion, lowering fuel adiabat and increasing neutron production. This technique, inspired by direct-drive adiabat shaping, shows promise for indirect-drive implosions.
Area of Science:
- Physics
- Plasma Physics
- Nuclear Fusion
Background:
- Inertial confinement fusion (ICF) relies on precise implosion dynamics.
- Previous work established direct-drive adiabat shaping for improved ICF performance.
- Indirect-drive ICF typically uses a different pulse shaping strategy.
Purpose of the Study:
- To propose and evaluate a design adjustment for the high foot laser pulse in indirect-drive ICF.
- To investigate the impact of a laser power trough on fuel adiabat, compression, and neutron yield.
- To assess the feasibility of adiabat shaping in indirect-drive ICF implosions.
Main Methods:
- Simulations of integrated hohlraum physics were performed.
- A modified laser pulse shape featuring a power decrease between pulses was modeled.
- Comparison with established direct-drive adiabat shaping techniques.
Main Results:
- The proposed adjustment is predicted to lower the fuel adiabat and increase neutron production.
- A similar ablation front growth is maintained.
- Hohlraum simulations indicate sufficient cooling for decaying shocks and symmetry control.
Conclusions:
- Adiabat shaping may be achievable in indirect-drive ICF implosions.
- The modified laser pulse technique shows initial experimental efficacy.
- This approach offers a potential pathway to enhance ICF performance.
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