For laser-plasma interactions at moderate intensities the conduction of heat cannot be captured by the classical Spitzer-HÄarm expression and an accurate treatment for non-local electron transport is necessary. A suitable method needs to discriminate between local electrons, that behave in accordance to the classical thermal conduction, and non-local electrons, that have very long mean free paths and di®use energy all over the physical domain. Two widely known and promising schemes are examined in detail: SNB [Schurtz et al. PoP (2000)] and CMG [Manheimer et al. PoP (2008)]. Both models have been implemented in the hydrodynamic code DUED and benchmarked against the fully kinetic Vlasov- Fokker-Plank codes OSHUN and KETS. Both schemes calculate the right amount of °ux in the limit of steep temperature gradients, and for the test problem of hot- spot relaxation they are both generally well-behaved at hydrodynamic time-scales (» 30¿ei). However, at kinetic time-scales (up to » 30¿ei) the SNB model better approximates the kinetic solution. 1D and 2D shock ignition simulations will be presented and the role of non-local e®ects in the implosion and ignition stages will be discussed.
Validation of non-local electron transport approaches, application to shock ignition / Marocchino, Alberto; Atzeni, Stefano; Schiavi, Angelo; M., Tzoufras; J., Mallet; P., Nicolaï; J. L., Feugeas; V., Tikhonchuk; A. R., Bell. - In: BULLETIN OF THE AMERICAN PHYSICAL SOCIETY. - ISSN 0003-0503. - STAMPA. - 57(12):(2012), p. 342. (Intervento presentato al convegno 54th Annual Meeting of the Division of Plasma Physics, American Physical Society tenutosi a Providence, RI nel October 29 - November 2, 2012).
Validation of non-local electron transport approaches, application to shock ignition
MAROCCHINO, ALBERTO;ATZENI, Stefano;SCHIAVI, ANGELO;
2012
Abstract
For laser-plasma interactions at moderate intensities the conduction of heat cannot be captured by the classical Spitzer-HÄarm expression and an accurate treatment for non-local electron transport is necessary. A suitable method needs to discriminate between local electrons, that behave in accordance to the classical thermal conduction, and non-local electrons, that have very long mean free paths and di®use energy all over the physical domain. Two widely known and promising schemes are examined in detail: SNB [Schurtz et al. PoP (2000)] and CMG [Manheimer et al. PoP (2008)]. Both models have been implemented in the hydrodynamic code DUED and benchmarked against the fully kinetic Vlasov- Fokker-Plank codes OSHUN and KETS. Both schemes calculate the right amount of °ux in the limit of steep temperature gradients, and for the test problem of hot- spot relaxation they are both generally well-behaved at hydrodynamic time-scales (» 30¿ei). However, at kinetic time-scales (up to » 30¿ei) the SNB model better approximates the kinetic solution. 1D and 2D shock ignition simulations will be presented and the role of non-local e®ects in the implosion and ignition stages will be discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.