Plasma and Fusion Research
Volume 9, 3404090 (2014)
Regular Articles
- Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
- 1)
- National Institute for Fusion Science, Oroshi-cho, Toki 509-5292, Japan
- 2)
- Institute for Laser Technology, Yamadaoka, Suita 565-0871, Japan
- 3)
- Institute of Laser Engineering, Osaka University, Yamadaoka, Suita 565-0871, Japan
Abstract
The calculation of the laser absorption is very important for implosion simulations to capture precisely its dynamics. In many implosion simulations, the laser absorption is computed by the use of ray tracing. However, the conventional ray tracing method has the problem that it generates a non-physical absorption distribution because it represents a laser beam by a finite number of rays. Such a non-physical distribution on the target surface could be numerical perturbations that grow drastically due to Rayleigh-Taylor instability. An enormous number of rays are required to avoid such a non-physical distribution. This results in high computational costs. Thus, we have developed a new method of ray tracing that essentially generates no non-physical absorption distribution. In the new algorithm, rays are inversely traced from grid points unlike the conventional method. This paper presents the new algorithm and a preliminary implosion simulation where the pressure perturbation due to the non-uniformity of the irradiation is computed by the use of this new ray tracing.
Keywords
inertial confinement fusion, implosion simulation, laser plasma interaction, ray tracing, hydrodynamics
Full Text
References
- [1] S. Atzeni and J. Meyer-ter-Vehn, The Physics of Inertial Fusion (Clarendon Press, Oxford, 2004).
- [2] H. Takabe et al., Phys. Fluids 28, 3676 (1985).
- [3] F. Hattori et al., Phys. Fluids 29, 1719 (1986).
- [4] A. Casner et al., Phys. Plasmas 19, 082708 (2012).
- [5] H. Nagatomo et al., J. Plasmas Phys. 72, 791 (2006).
- [6] S. Atzeni, Comput. Phys. Commun. 43, 107 (1986).
- [7] M. Temporal et al., Phys. Plasmas 8, 1363 (2001).
- [8] M. Temporal and B. Canaud, Eur. Phys. J. D 55, 139 (2009).
- [9] A. Sunahara et al., Plasma Fusion Res. 3, 043 (2008).
- [10] R.S. Craxton and R.L. McCrory, J. Appl. Phys 56, 108 (1984).
- [11] H. Sakagami and K. Nishihara, Phys. Rev. Lett. 65, 432 (1990).
- [12] N. Miyanaga et al., Proceedings of 1st International Conference on Solid State Lasers for Application to Inertial Confinement Fusion, CA, SPIE 2663, 183 (1996).
- [13] M. Heya et al., Laser Part. Beams 19, 267 (2001).
This paper may be cited as follows:
Takumi YANAGAWA, Hitoshi SAKAGAMI, Atsushi SUNAHARA and Hideo NAGATOMO, Plasma Fusion Res. 9, 3404090 (2014).