Simulation On The Compression Of Magnetized Target Fusion Plasma By Imploding Solid Liner

Magneto-inertial fusion(MIF)is intermeadate approach compared with magnetic confinement fusion(MCF)and inertial confinement fusion(ICF).In MIF,the magnetized plasma target can be compressed to fusion ignition conditions by high speed shell driven by high power laser or pulse current.MIF has higher plasma dengsity and short plasma confinement time compared to MCF.MIF paroaches take advantage of an embedded magnetic field to improve plasma energy confinement by reducing thermal conduction of alpha particles and electrons in plasmas relative to ICF.As one of MIF approaches,magnetized target fusion(MTF)based on field-reversed configuration(FRC)is mainly achieved igniton condition via imploding solid liner driven by larger pulse current.MTF involves three physical processes including formation of FRC,transition of FRC to the compression area from formation tube,and compression of FRC target.As a last stage,compression of FRC by shell can be divided into laser and magnetic field one.The compression by imploding solid liner has its unique characters.First one is the maches of confinement time and space length.Sencond is the clearn driven systm due to the solid liner.Based on the asymptotic theory,the code FRC-GS is developed to solve the two dimensional Grad-Shafranov equation in field-reversed configuration.Via the code,the field-reversed configuration with different elongations is investigated in the present paper.It is obtained that the plasma density gradient increase linearly with the magnetic flux in the FRC center,and at the separatrix,the density gradient becomes steepen due to the high magnetic field distribution.The results also show that the plasma density in the closed field region increases with the density at the separatrix which imply that FRC embodies strong confinement ability.Based on the single particle theory and integral arithmetic,the code-ALFA is exploited to analyze the energy deposition of non-thermal alpha particle in the cylindrical and spherical magnetized target.It is found that the energy deposition of alpha particle in the cylindrical magnetized target is larger than that in the spherical one under the same background magnetic field,D-T plasma density and plasma temperature;secondly,there exists a work region of magnetic field for alpha particle average energy deposition.If the magnetic field exceeds the work region,the alpha particle average energy deposition stays at a constant nearly.As for the different geometry scale,the work region of the magnetic field affecting the energy deposition of alpha particle appears differently;finally,the alpha particle energy deposition increases with the D-T plasma density.Study on the compression of field-reversed configuration(FRC)by a magnetic driven solid liner is carried out based a one-dimension code.In the investigation,plasma heating effect by alpha particles is taken into account.Numerical result shows that the self-heating of alpha particles to DT plasma mainly occurs in the vicinity of O-point of the field-reversed configuration target.The plasma ignition region is divided into two parts:low density ignition region near the central axis and high density ignition region in the O-point area.Before FRC plasma target expansion,energy of alpha particles is well confined nearby the O-point by compressed magnetic.The DT plasma volume burning exists in short time(approximately 0.1 us)after a maximum convergence ratio of solid liner.And compressed strong magnetic field degrades the propagation of FRC plasma burning.The present paper consists of 9 chapters.Introduction is given in Chapter 1;Chapter 2 is reviewing of MTF reseach;The principle of MTF is introduced Chapter 3;Chapter 4 is the physical model of magnetized plasma target in the elastic-plastic reactive magnetic hydrodynamic code SSS-MHD;Chapter 5 is simulation of Grad-sharanov equation in FRC plasma;Chapter 6 is analysis of alpha particle energy deposition to DT plasma;Chapter 7 is simulation of solid liner imploding process;Chapt 8 is simulation of compression on FRC plasma target by magnetic-driven solid liner.Chapter 9 is summary of the present paper and outlook of reseach topics in future.