Theoretical study of symmetry of flux onto a capsule
- Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China)
- Shanghai Institute of Laser Plasma, China Academy of Engineering Physics, Shanghai 201800 (China)
An analytic model to describe the flux asymmetry onto a capsule based on the viewfactor approximation is developed and verified with numerical simulations. By using a nested spheres technique to represent the various sources of flux asymmetry, the model can treat spherically and cylindrically symmetric hohlraums, e.g., cylinder, elliptic, and rugby. This approach includes the more realistic case of frequency-dependent flux asymmetry compared with the more standard frequency-integrated or single-frequency approaches [D. W. Phillion and S. M. Pollaine, Phys. Plasmas 1, 2963 (1994)]. Correspondingly, the approach can be used to assess x-ray preheat asymmetry generated from localized laser absorption in the high-Z hohlraum wall. For spherical hohlraums with 4, 6, or 8 laser entrance holes (LEHs), an optimal configuration of LEHs, laser spot placement, and angle-of-incidence of the single-ringed laser beams is defined. An analogy between minimizing the flux asymmetry onto a capsule and the Thomson problem of point charge placement on a sphere for minimized energy is shown.
- OSTI ID:
- 22493742
- Journal Information:
- Physics of Plasmas, Vol. 22, Issue 9; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
Similar Records
High-temperature hohlraum designs with multiple laser-entrance holes
First study of Hohlraum x-ray preheat asymmetry inside an ICF capsule
Related Subjects
GENERAL PHYSICS
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ASYMMETRY
CAPSULES
COMPUTERIZED SIMULATION
CYLINDRICAL CONFIGURATION
FREQUENCY DEPENDENCE
INCIDENCE ANGLE
LASER CAVITIES
PHOTON BEAMS
POINT CHARGE
RING LASERS
SPHERES
SPHERICAL CONFIGURATION
SYMMETRY
X RADIATION