In connection to the Cone Focussed Fast Ignition scheme, for the first time we consider hydrodynamic mechanisms for the contamination of the ignition spark by the cone high-Z material. Kelvin-Helmholtz and Richtmyer-Meshkov instabilities at the cone-shell interface are responsible for the mixing process. For these instabilities we present linear and quasi-linear calculations performed in relevant situations at level of real matter equation of state. The results are used to get a rough order of magnitude estimate for the mass of the entrained high-Z material (specifically Au). This quantity is then compared with the one that makes a spark in a mixture Au-DT practically impossible to ignite. Reference mixing conditions are microscopic mixing (atomic mixing) and macroscopic mixing (blob mixing). For microscopic mixing the ignition calculations are performed by 2D simulations, whereas for macroscopic mixing the effect on the ignition thresholds is evaluated by estimating the energy drain due to a dispersion of high-Z blobs into the fuel. The comparison of the amount of contaminant that makes ignition impossible with that entrained by the imploding shell indicates that the latter can be substantially larger. This result suggests that the problem may exist, the final conclusion requiring simulations to get more refined estimates of (i) the amount of entrained material, (ii) the distribution of the contaminant into the fuel and (iii) the mixing mode (microscopic versus macroscopic).
|Publication status||Published - 2004|
|Event||Third International Conference on Inertial Fusion Sciences and Applications, IFSA 2003 - , United States|
Duration: 1 Jan 2004 → …
|Conference||Third International Conference on Inertial Fusion Sciences and Applications, IFSA 2003|
|Period||1/1/04 → …|
All Science Journal Classification (ASJC) codes
Caruso, A., & Strangio, C. (2004). Ignition thresholds for deuterium-tritium mixtures contaminated by high-Z material. Paper presented at Third International Conference on Inertial Fusion Sciences and Applications, IFSA 2003, United States.