活动标题:The updated design of hybrid-drive ignition target for ICF and experiments in pressure boost and smoothing on SG-III laser facility
主讲人: 贺贤土院士
活动时间:2018年06月26日 10:00
活动地点: 图书馆二号报告厅(犀浦校区)
主办单位:物理科学与技术学院
演讲人简介:
贺贤土理论物理学家,中国科学院院士,研究员、博士生导师。1962 年浙江大学物理系理论物理专业毕业后进入中国工程物理研究院,在北京应用物理与计算数学研究所工作。1986年至1987 年底任美国马里兰大学高级访问学者。1988 年至1997 年任北京应用物理与计算数学研究所科技委员会副主任、副所长(1991 年起)。1995 年被选为中国科学院院士。1996 年至2001 年任国家“863 计划”惯性约束聚变直属主题首席科学家。2001 年至2006 年先后任中国科学院数理学部常委、副主任、主任和中国科学院学部主席团成员和执行委员会成员。曾兼任科技部国家“863 计划”顾问组成员、国家自然科学奖评审委员会委员,以及国家中长期科技规划战略能源组组长委员等职。现任北京大学应用物理与技术研究中心主任;兼任中国工程物理研究院专家委员会委员、“863 计划”领域委员会委员、国家重大专项高级科学顾问、浙江大学理学院名誉院长、高功率激光物理国家重点实验室学术委员会主任、中国计算物理学会理事长和Communications in Computational Physics国际杂志主编等职。
摘要:
In laser-drive inertial confinement fusion (ICF), a new hotspot-ignition scheme by hybrid-drive (HD) approach that combined both indirect-drive (ID) and direct-drive (DD) was proposed [1] recently. First, a layered capsule is ablated by lower ID temperature, it results in the pre-compression of fusion fuel by implosion dynamics and also the formation of a long-scale corona plasma. Then, the DD lasers with a flattop pulse of ~2ns duration, in the last ID pulse duration, are incident on and absorbed near the critical surface far from the ID ablation front at capsule surface and generate a supersonic electronic-thermal wave (ETW) in which non-uniformities caused by the DD lasers are significantly smoothed during propagation in the long-scale ID corona plasma. The supersonic ETW slows down to a sonic ETW with high electronic pressure, which behaves like a “snowplow” that piles up the low corona plasma density into high density platform between sonic wave front and the ID ablation front, where the HD plasma pressure far higher than the traditional ID ablation pressure is generated and drives a high implosion velocity. The boosted HD pressure provides PdV work large enough to the hotspot and suppresses hotspot deformation and hydrodynamic instabilities, resulting in non-stagnation hotspot ignition. In this talk, we present the updated HD ignition target design and the experiments in the HD pressure boost and smoothing of supersonic ETW on SG-III laser facility.