Debris and Shrapnel Mitigation Procedure for NIF Experiments
All experiments at the National Ignition Facility (NIF) will produce debris and shrapnel from vaporized, melted, or fragmented target/diagnostics components. For some experiments mitigation is needed to reduce the impact of debris and shrapnel on optics and diagnostics. The final optics, e.g., wedge focus lens, are protected by two layers of debris shields. There are 192 relatively thin (1-3 mm) disposable debris shields (DDS's) located in front of an equal number of thicker (10 mm) main debris shields (MDS's). The rate of deposition of debris on DDS's affects their replacement rate and hence has an impact on operations. Shrapnel (molten and solid) can have an impact on both types of debris shields. There is a benefit to better understanding these impacts and appropriate mitigation. Our experiments on the Omega laser showed that shrapnel from Ta pinhole foils could be redirected by tilting the foils. Other mitigation steps include changing location or material of the component identified as the shrapnel source. Decisions on the best method to reduce the impact of debris and shrapnel are based on results from a number of advanced simulation codes. These codes are validated by a series of dedicated experiments. One of the 3D codes, NIF's ALE-AMR, is being developed with the primary focus being a predictive capability for debris/shrapnel generation. Target experiments are planned next year on NIF using 96 beams. Evaluations of debris and shrapnel for hohlraum and capsule campaigns are presented.
- Research Organization:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 922113
- Report Number(s):
- UCRL-CONF-234490; TRN: US200803%%242
- Resource Relation:
- Journal Volume: 112; Journal Issue: 3; Conference: Presented at: IFSA Conference, Kobe, Japan, Sep 09 - Sep 14, 2007
- Country of Publication:
- United States
- Language:
- English
Debris mitigation in pinhole-apertured point-projection backlit imaging
|
journal | November 2004 |
Late-time simulation of National Ignition Facility hohlraums
|
journal | May 2004 |
Similar Records
Experiments for the Validation of Debris and Shrapnel Calculations
Summary of Disposable Debris Shields (DDS) Analysis for Development of Solid Debris Collection at NIF