FPN02-38

Sandia Z Experiments Show Scaling to High Yield

May 27, 2002

Experiments on the Z facility at Sandia National Laboratories, Albuquerque, combined with 2D radiation hydrodynamic simulations, indicate that the facility can be used to develop physics scaling laws necessary for high yield (greater than 200 megajoues) inertial confinement fusion. In the experiments, a double Z pinch, driving a cylindrical secondary hohlraum from each end, produced time-averaged radiation fields uniform to within 2-4 percent. Simulations indicated fusion capsule convergence ratios of at least 10 and average distortions from sphericity of less than 30% are possible on the Z facility. The results appear in a paper, "Double Z-Pinch Hohlraum Drive with Excellent Temperature Balance for Symmetric Inertial Confinement Fusion Capsule Implosions" by M. E. Cuneo et al., in the May 27 issue of Physical Review Letters. It can be accessed at: http://link.aps.org/abstract/PRL/v88/e215004

Fusion power systems for practical purposes require capsule convergence ratios of about 30, radiation uniformity of 1-2% and distortions from sphericity of no worse than 25-50 percent.

The results show that it should be possible to obtain, in the near term, reliable physics scaling information that could be used to justify a high yield facility at an early date.

Z pinches have the attractive feature of being relatively low in cost. Concepts are being developed to permit these currently single shot experiments to become repetitively pulsed. Fusion power plants, based on the Z pinch, would pulse about once every ten seconds and would have "recyclable transmission lines" that would be replaced automatically between pulses.

For further information contact: Keith Matzen (mkmatze@sandia.gov).