Instability growth for magnetized liner inertial fusion seeded by electro-thermal, electro-choric, and material strength effects

A critical limitation of magnetically imploded systems such as magnetized liner inertial fusion (MagLIF) [Slutz et al., Phys. Plasmas 17, 056303 (2010)] is the magneto-Rayleigh-Taylor (MRT) instability which primarily disrupts the outer surface of the liner. MagLIF-relevant experiments have showed large amplitude multi-mode MRT instability growth growing from surface roughness [McBride et al., Phys. Rev. Lett. 109, 135004 (2012)], which is only reproduced by 3D simulations using our MHD code Gorgon when an artificially azimuthally correlated initialisation is added. We have shown that the missing azimuthal correlation could be provided by a combination of the electro-thermal instability (ETI) and an “electro-choric” instability (ECI); describing, respectively, the tendency of current to correlate azimuthally early in time due to temperature dependent Ohmic heating; and an amplification of the ETI driven by density dependent resistivity around vapourisation. We developed and implemented a material strength model in Gorgon to improve simulation of the solid phase of liner implosions which, when applied to simulations exhibiting the ETI and ECI, gave a significant increase in wavelength and amplitude. Full circumference simulations of the MRT instability provided a significant improvement on previous randomly initialised results and approached agreement with experiment.

[1]  S. Slutz,et al.  Simulations of electrothermal instability growth in solid aluminum rodsa) , 2013 .

[2]  R. Mcbride,et al.  Magnetically Driven Implosions for Inertial Confinement Fusion at Sandia National Laboratories , 2012, IEEE Transactions on Plasma Science.

[3]  B. Blue,et al.  Beryllium liner implosion experiments on the Z accelerator in preparation for magnetized liner inertial fusiona) , 2012 .

[4]  B. Blue,et al.  Penetrating radiography of imploding and stagnating beryllium liners on the Z accelerator. , 2012, Physical review letters.

[5]  S. Slutz,et al.  Electrothermal instability growth in magnetically driven pulsed power liners , 2012 .

[6]  Moscow,et al.  Dynamics of volumetrically heated matter passing through the liquid-vapor metastable states ✩ , 2012, 1205.2579.

[7]  S. Slutz,et al.  High-gain magnetized inertial fusion. , 2012, Physical review letters.

[8]  G. R. Bennett,et al.  Measurements of magneto-Rayleigh-Taylor instability growth during the implosion of initially solid Al tubes driven by the 20-MA, 100-ns Z facility. , 2010, Physical review letters.

[9]  S. Slutz,et al.  Pulsed-power-driven cylindrical liner implosions of laser preheated fuel magnetized with an axial field , 2010 .

[10]  Ramon Joe Leeper,et al.  The refurbished Z facility : capabilities and recent experiments. , 2009 .

[11]  V. Oreshkin.  Overheat instabilities in the electric explosion of wires , 2009 .

[12]  Erik Asphaug,et al.  Validation of numerical codes for impact and explosion cratering: Impacts on strengthless and metal targets , 2008 .

[13]  V. Oreshkin.  Thermal instability during an electrical wire explosion , 2008 .

[14]  Astronomy,et al.  The Evolution of Magnetic Tower Jets in the Laboratory and in Astrophysics , 2006, astro-ph/0611441.

[15]  Gareth S. Collins,et al.  A strain-based porosity model for use in hydrocode simulations of impacts and implications for transient crater growth in porous targets , 2006 .

[16]  C. Jennings,et al.  X-ray generation mechanisms in three-dimensional simulations of wire array Z-pinches , 2004 .

[17]  Gareth S. Collins,et al.  Modeling damage and deformation in impact simulations , 2004 .

[18]  M. Desjarlais.  Practical Improvements to the Lee‐More Conductivity Near the Metal‐Insulator Transition , 1999 .

[19]  J. Meyer-ter-Vehn,et al.  AN EQUATION OF STATE CODE FOR HOT DENSE MATTER, BASED ON THE QEOS DESCRIPTION , 1998 .

[20]  Derzon,et al.  The physics of fast Z pinches , 1998 .

[21]  G. Zimmerman,et al.  A new quotidian equation of state (QEOS) for hot dense matter , 1988 .

[22]  R. More,et al.  An electron conductivity model for dense plasmas , 1984 .

[23]  C. W. Hirt,et al.  SALE: a simplified ALE computer program for fluid flow at all speeds , 1980 .

[24]  G. R. Johnson,et al.  Fracture characteristics of three metals subjected to various strains, strain rates, temperatures and pressures , 1985 .

[25]  E. Harris.  Rayleigh-Taylor Instabilities of a Collapsing Cylindrical Shell in a Magnetic Field , 1962 .

[26]  S. Chandrasekhar.  Hydrodynamic and Hydromagnetic Stability , 1961 .