Experimental Evidence of Kinetic Effects in Indirect-Drive Inertial Confinement Fusion Hohlraums

Shan, Lianqiang; Cai, Hong-bo; Zhang, W S; Tang, Qi; Zhang, F; Song, Zifeng; Bi, Bo; Ge, Fengjun; Chen, J B; Liu, D X; Wang, W W; Yang, Z. H.; Qi, Weizhi; Tian, Chao; Yuan, Zhao; Zhang, B; Yang, Lei; Jiao, Jing; Cui, Bo; Zhou, Weimin; Cao, Liangcai; Zhou, C. T.; Gu, Yuqiu; Zhang, B H; Zhu, Shaoping; He, X. T.

doi:10.1103/physrevlett.120.195001

Cited by 34 publications

(14 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Rinderknecht et al 30 pointed out the systematic abnormalities in the National Ignition Facility (NIF) implosion dataset suggest that kinetic physics may play a role, including inferred missing energy in the hohlraum, drive asymmetry in nearvacuum hohlraums, low areal density and high burn-averaged ion temperatures compared with mainline models, and low ratios between the DD-neutron and DT-neutron yields and inferred Ti. Shan et al 31 discussed that the kinetic shocks caused an anomalous large energy spread of the DD neutron signal and anomalous scaling of the neutron yield with the thickness of the CD layers which are not explicable using hydrodynamic mechanics and these findings are supported for the first time by experiments and simulations. Cai et al 32 presented a new framework that combines kinetics and hydrodynamics to simulate shock waves and hydrodynamic instabilities in plasmas with high density.…”

Section: Introductionmentioning

confidence: 99%

Nonequilibrium kinetics effects in Richtmyer-Meshkov instability and reshock process

Shan¹,

Xu²,

Wang³

et al. 2022

Preprint

View full text Add to dashboard Cite

Nonequilibrium kinetic effects are widespread in fluid systems and might have a significant impact on the inertial confinement fusion ignition process, and the entropy production rate is a key factor in accessing the compression process. But relevant research is little due to the lack of convenient physical model. In this work, we study the Richtmyer-Meshkov instability (RMI) and the reshock process by a two-fluid discrete Boltzmann method (DBM). The work starts from interpreting the experiment by Collins and Jacobs [J. Fluid Mech. 464, 113-136 (2002)]. Firstly, the DBM result for the perturbation amplitude evolution is in good agreement with that of experiment. It is found that shock wave causes substances near the substance interface to deviate more significantly from their thermodynamic equilibrium state. Greatly different from the case of normal shocking on unperturbed plane interface between two uniform media, which is well described by the Rankine-Hugoniot relations and where all Thermodynamic Non-Equilibrium (TNE) quantities quickly recover to zero behind the shock front, in the RMI case, the TNE quantities show complex but inspiring kinetic effects in the shocking process and behind the shock front. The kinetic effects are detected by two sets of TNE quantities. The first set are |∆ * 2 |, ∆ * 3,1 , ∆ * 3 , and ∆ * 4,2 . They correspond to the intensities of the Non-Organized Momentum Flux(NOMF), Non-Organized Energy Flux(NOEF), flux of NOMF and flux of NOEF. All the four TNE measures abruptly increase in the shocking process. ∆ * 3,1 and ∆ * 3 have the same dimension and show similar behaviors. They continue to increase in a much lower rate behind the shock front. |∆ * 2 | and ∆ * 4,2 have different dimensions, but show similar behaviors. They quickly decrease to be very small behind the shock front. The second set of TNE quantities are ṠNOMF , ṠNOEF and Ṡsum . They are entropy production rates due to NOMF, NOEF and their summation. It is found that the mixing zone is the primary contribution region to the ṠNOEF , while the flow field region excluding mixing zone is the primary contribution region to the ṠNOMF . Each substance behaves differently in terms of entropy production rate, and the light fluid has a higher entropy production rate than the heavy fluid.

show abstract

Section: Introductionmentioning

confidence: 99%

Nonequilibrium kinetics effects in Richtmyer-Meshkov instability and reshock process

Shan¹,

Xu²,

Wang³

et al. 2022

Preprint

View full text Add to dashboard Cite

show abstract

“…Zhang et al (2017) observed anomalous neutron yield in indirect-drive ICF, and they attributed it to electrostatic shock wave collisions. Some of the deuterium particles are accelerated to high energy by the electrostatic shock wave and react with centre plasmas by means of the beam-target reaction (Zhang et al 2017;Shan et al 2018). Other research such as that concerning laser-driven plasma collider (Fu et al 2015) also takes the beam-target reaction into account.…”

Section: Introductionmentioning

confidence: 99%

“…It is necessary to employ a precise calculation method in order to evaluate quantitatively the importance of the beam-target reaction rate in fusion. However, the traditional method (Yue et al 1993;Perkins et al 2000;He et al 2015;Zhang et al 2017;Shan et al 2018) ignores the transport process and may introduce large errors when the temperature and density along the transport path of incident plasmas vary obviously. An improved method is proposed in this paper, in which we take the transport process into account to eliminate the errors.…”

Section: Introductionmentioning

confidence: 99%

Improved numerical simulation model for nuclear reaction rate calculations in high-speed plasma collisions

Zeng,

Zhao,

Yang

et al. 2024

J. Plasma Phys.

View full text Add to dashboard Cite

Beam–target reactions in fusion plasmas play an important role in both magnetic confinement fusion and inertial confinement fusion in the condition of low-density plasmas with high-velocity interactions. The traditional method for calculating beam–target reaction rate neglects the transport process of incident particles in inhomogeneous plasmas, leading to errors providing that the temperature and density in the transport path of incident particles vary obviously. An improved method considering the transport process is proposed in this paper to eliminate the deficiencies. Then the method is employed in high-speed plasma collision studies. When the initial plasma density and temperature are set to $0.5\,{\rm g}\,{\rm cm}^{-3}$ and 100 eV, it is found that the beam–target reaction rate calculated by the traditional method is almost identical to that by our method if the collision velocity is less than 600 km s $^{-1}$ . However, the traditional method is not suitable for study as the collision velocity gets higher, inducing obvious differences, which can reach 70 % at 1000 km s $^{-1}$ . The improved method will make large corrections to evaluate the importance of the non-negligible beam–target reaction for inertial confinement fusion schemes with large implosion velocity such as double-cone ignition and impact ignition, in which the high-speed plasmas collide with each other to realize plasma ignition.

show abstract

“…The modeling and design of inertial fusion targets mainly rely on radiation hydrodynamic (RH) codes nowadays. However, the conditions are not always satisfied, ion kinetic effects and material mixing outside the scope of RH simulations have been considered as the possible reason to explain the anomalies in fusion yield in recent ICF experiments [8]. While kinetic treatment (e.g., Vlasov-Fokker-Planck methods [9, 10] and Monte-Carlo kinetic particle code [11]) may improve our understanding of material mixing and ion kinetic effects in ICF experiments, it falls short of offering shell dynamics, leaving uncertainties compared to recent ICF experimental observations.…”

Section: Introductionmentioning

confidence: 99%

Simulation and assessment of material mixing in an indirect-drive implosion with a hybrid fluid-PIC code

Cai

Zhang²,

Ge³

et al. 2023

Front. Phys.

View full text Add to dashboard Cite

Hybrid fluid-PIC simulations aimed at a better understanding of the implosion physics and the material mixing into the hot spot are described. The application of a hybrid fluid-PIC code is motivated by the difficulty of modeling the material mixing by the commonly used radiation hydrodynamic simulations. Hybrid fluid-PIC techniques, which treat the ions with the traditional particle-in-cell method, and electrons with a massless fluid, are more adaptable to handle the heating of DT fuel through PdV work and the material mixing near the DT ice-gas interface and ablator-fuel interface of a compressed capsule. During implosion shock convergence, significant reactant temperature separation and a noticeable amount of material mixing are observed, both of which have important consequences for estimating neutron yield and the understanding of implosions. Physical explanations for these phenomena are discussed, with the non-equilibrium effect in the hotspot and hydrodynamic instabilities at the interface as the likely explanation, respectively. The hybrid fluid-PIC method would be helpful to test the phenomenological fluid model describing the material mixing in ICF implosion.

show abstract

Experimental Evidence of Kinetic Effects in Indirect-Drive Inertial Confinement Fusion Hohlraums

Cited by 34 publications

References 25 publications

Nonequilibrium kinetics effects in Richtmyer-Meshkov instability and reshock process

Nonequilibrium kinetics effects in Richtmyer-Meshkov instability and reshock process

Improved numerical simulation model for nuclear reaction rate calculations in high-speed plasma collisions

Simulation and assessment of material mixing in an indirect-drive implosion with a hybrid fluid-PIC code

Contact Info

Product

Resources

About