Inertial fusion energy (IFE) has been considered a promising, nearly inexhaustible source of sustainable carbon-free power for the world's energy future. It has long been recognized that the control of hydrodynamic...Inertial fusion energy (IFE) has been considered a promising, nearly inexhaustible source of sustainable carbon-free power for the world's energy future. It has long been recognized that the control of hydrodynamic instabilities is of critical importance for ignition and high-gain in the inertial-confinement fusion (ICF) hot-spot ignition scheme. In this mini-review, we summarize the progress of theoretical and simulation research of hydrodynamic instabilities in the ICF central hot-spot implosion in our group over the past decade. In order to obtain sufficient understanding of the growth of hydrodynamic instabilities in ICF, we first decompose the problem into different stages according to the implosion physics processes. The decomposed essential physics pro- cesses that are associated with ICF implosions, such as Rayleigh-Taylor instability (RTI), Richtmyer-Meshkov instability (RMI), Kelvin-Helmholtz instability (KHI), convergent geometry effects, as well as perturbation feed-through are reviewed. Analyti- cal models in planar, cylindrical, and spherical geometries have been established to study different physical aspects, including density-gradient, interface-coupling, geometry, and convergent effects. The influence of ablation in the presence of preheating on the RTI has been extensively studied by numerical simulations. The KHI considering the ablation effect has been discussed in detail for the first time. A series of single-mode ablative RTI experiments has been performed on the Shenguang-II laser facility. The theoretical and simulation research provides us the physical insights of linear and weakly nonlinear growths, and nonlinear evolutions of the hydrodynamic instabilities in ICF implosions, which has directly supported the research of ICF ignition target design. The ICF hot-spot ignition implosion design that uses several controlling features, based on our current understanding of hydrodynamic instabilities, to address shell implosion stability, has been briefly described, severa展开更多
在复数范围内讨论了Modified Korteweg de Vries(mKdV)方程孤立波解的结构.发现在一定参数情况下,该解的实部为反向或同向双峰孤立波而虚部为双扭结状孤立波(或反之).接着对文献中提出的有限差分格式进行了理论分析,表明其为二阶精度的...在复数范围内讨论了Modified Korteweg de Vries(mKdV)方程孤立波解的结构.发现在一定参数情况下,该解的实部为反向或同向双峰孤立波而虚部为双扭结状孤立波(或反之).接着对文献中提出的有限差分格式进行了理论分析,表明其为二阶精度的条件稳定格式,并解析地给出了数值稳定性条件.最后采用该格式对mKdV方程描述的该类波的动力学稳定性进行了数值研究,发现既存在动力学稳定的孤立波,也存在动力学不稳定的孤立波.展开更多
We derive the dimensionless dynamic equations of two-photon lasers with A atomic level configuration by using the quantum Langevin equation method with the considerations of atomic coherence and injected classical fie...We derive the dimensionless dynamic equations of two-photon lasers with A atomic level configuration by using the quantum Langevin equation method with the considerations of atomic coherence and injected classical fields. Then we analyze the stability and the chaotic dynamics of the two-photon laser by calculating the bifurcation diagram and the maximum Lyapunov exponent (MLE). Our results show that the Lorenz strange attractors and one-focus strange attractors can exist in this system, and the chaos can be induced or inhibited by the injected classical fields via Hopfbifurcations or crises, while the atomic coherence induces chaos via crises, and inhibit chaos via Hopf bifurcation or crises.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11275031,11675026,11475032,11475034,11575033,and 11274026)the Foundation of President of Chinese Academy of Engineering Physics(Grant No.2014-1-040)the National Basic Research Program of China(Grant No.2013CB834100)
文摘Inertial fusion energy (IFE) has been considered a promising, nearly inexhaustible source of sustainable carbon-free power for the world's energy future. It has long been recognized that the control of hydrodynamic instabilities is of critical importance for ignition and high-gain in the inertial-confinement fusion (ICF) hot-spot ignition scheme. In this mini-review, we summarize the progress of theoretical and simulation research of hydrodynamic instabilities in the ICF central hot-spot implosion in our group over the past decade. In order to obtain sufficient understanding of the growth of hydrodynamic instabilities in ICF, we first decompose the problem into different stages according to the implosion physics processes. The decomposed essential physics pro- cesses that are associated with ICF implosions, such as Rayleigh-Taylor instability (RTI), Richtmyer-Meshkov instability (RMI), Kelvin-Helmholtz instability (KHI), convergent geometry effects, as well as perturbation feed-through are reviewed. Analyti- cal models in planar, cylindrical, and spherical geometries have been established to study different physical aspects, including density-gradient, interface-coupling, geometry, and convergent effects. The influence of ablation in the presence of preheating on the RTI has been extensively studied by numerical simulations. The KHI considering the ablation effect has been discussed in detail for the first time. A series of single-mode ablative RTI experiments has been performed on the Shenguang-II laser facility. The theoretical and simulation research provides us the physical insights of linear and weakly nonlinear growths, and nonlinear evolutions of the hydrodynamic instabilities in ICF implosions, which has directly supported the research of ICF ignition target design. The ICF hot-spot ignition implosion design that uses several controlling features, based on our current understanding of hydrodynamic instabilities, to address shell implosion stability, has been briefly described, severa
文摘在复数范围内讨论了Modified Korteweg de Vries(mKdV)方程孤立波解的结构.发现在一定参数情况下,该解的实部为反向或同向双峰孤立波而虚部为双扭结状孤立波(或反之).接着对文献中提出的有限差分格式进行了理论分析,表明其为二阶精度的条件稳定格式,并解析地给出了数值稳定性条件.最后采用该格式对mKdV方程描述的该类波的动力学稳定性进行了数值研究,发现既存在动力学稳定的孤立波,也存在动力学不稳定的孤立波.
基金The project supported in part by the Natural Science Foundation of Jiangsu Province of China under Grant No. BK2005062
文摘We derive the dimensionless dynamic equations of two-photon lasers with A atomic level configuration by using the quantum Langevin equation method with the considerations of atomic coherence and injected classical fields. Then we analyze the stability and the chaotic dynamics of the two-photon laser by calculating the bifurcation diagram and the maximum Lyapunov exponent (MLE). Our results show that the Lorenz strange attractors and one-focus strange attractors can exist in this system, and the chaos can be induced or inhibited by the injected classical fields via Hopfbifurcations or crises, while the atomic coherence induces chaos via crises, and inhibit chaos via Hopf bifurcation or crises.