Energy Conversion And X-ray Emission In Inertial Confinement Fusion

Nowadays,with the further study of the ignition of Inertial Confinement Fusion(ICF),the energy conversion and X-ray emission in this process has attracted extensive attentions.The X-ray emission is the key process of Indirect-driven ICF,because it has important influence in the ablation and compression of the target.For the laser-indirectly-driven ICF,the model of laser interaction with solid targets is used to study the laser-to-X-ray conversion.There are many different ways of enhancing laser-to-X-ray conversion efficiency until now,but more practical way of enhancing laser to X-ray conversion efficiency and optimizing X-ray emission spectrum is still needed.While for the Z-pinch-driven ICF,the complete and correct simulation code is the key at present.Our work is devoted to study the detailed energy conversion X-ray emission and X-ray emission in laser and Z-pinch directly driven ICF in order to enhance the X-ray conversion efficiency for laser-driven ICF,and analyze the dependences of energy conversion and X-ray emission on several key parameters for Z-pinch-driven ICF..Firstly,the counter-propagating(C-P)lasers scheme is proposed in laser irradiating solid targets.Simulations are performed by one-dimensional radiation hydrodynamics code Multi-1D.Simulation results show that the laser to X-ray conversion efficiency for the C-P lasers case has a 13% enhancement compared with the single laser case because of the lower ion kinetic energy and electron internal energy.Futhermore,the X-ray emission spectrum shows that the enhancement is mainly from the enhanced soft X-ray emission and supperessed M-band emission.We also study the X-ray emission and energy conversion in Z-pinch-driven ICF.We have developed the code based on Z-pinch 0-dimensional model,and combined this code with Multi-1D.After that,simulations were performed to study the detailed energy conversions for two main processes and analyze the dependences of X-ray emission on several key parameters,including the maximum of current,linear mass of wire array,radius of wire array,radius of foam,and density of foam.The results show that the influence of maximum of current is mainly on the kinetic energy of wire array,and the parameters of wire array mainly affect the process of Z-pinch because there is a best kinetic energy for each wire array parameters.The foam can result in the decreased radiation,while the foam is important for the formation of hohlraum,thus the parameters of foam need choose carefully.