Stabilization of ablative Rayleigh-Taylor instability due to change of the Atwood number.
Recent experiment [S.G. Glendinning et al., Phys. Rev. Lett. 78, 3318 (1997)] showed that the measured growth rate of laser ablative Rayleigh-Taylor (RT) instability with preheating is about 50% of the classic value and is reduced by about 18% compared with the simulated value obtained with the computer code LASNEX. By changing the temperature variation of the electron thermal conductivity at low temperatures, the density profile from the Bhatnagar-Gross-Krook approximation is recovered in the simulation, and the simulated RT growth rate is in good agreement with the experimental value from Glendinning et al. The preheated density profile on ablative RT stablization is studied numerically. A change of the Atwood number in the preheating case also leads to RT stabilization. The RT growth formula gamma=square root of [Akg/(1+AkL)] - 2kV(a) agrees well with experiment and simulation, and is appropriate for the preheating case.
Ye
Wenhua
W
Department of Physics, Zhejiang University, Hangzhou 310028, People's Republic of China. Ye_wenhua@mail.iapcm.ac.cn
Zhang
Weiyan
W
He
X T
XT