The University of Osaka · 물리·천문학
Takabe 교수의 연구실은 레이저 플라즈마와 핵융합 안정성에 중점을 두며, 특히 충격압축형 핵융합에서 발생하는 레이일리-타일러 불안정성의 억제 메커니즘을 이론적·수치적 방법으로 연구하고 있습니다. 비균일한 플라즈마에서의 비국소 전자 전도성과 밀도 기반의 불안정성 억제 효과를 규명하고, 이를 바탕으로 레이저 핵융합 타겟의 설계 원칙을 제시합니다. 또한 통합 시뮬레이션 코드 ILESTA 개발을 통해 타겟의 압축 동역학과 난류 혼합 메커니즘을 종합적으로 분석합니다. 이는 핵융합 에너지뿐 아니라 초신성 폭발의 난류 연소 메커니즘 등 천체물리학 응용까지 확장됩니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
A mathematical method for a fully self-consistent treatment of the Rayleigh–Taylor instability is developed by solving the linearized fluid equations as an eigenvalue problem. The method is applied to analyze the instability in stationary ablating plasmas with strong inhomogeneity. A reduction of growth rate compared to the classical value is found. The importance of a self-consistent treatment of the Rayleigh–Taylor instability is shown by comparing the result with the growth rate estimated by
Abstract Thanks to a rapid progress of high-power lasers since the birth of laser by T. H. Maiman in 1960, intense lasers have been developed mainly for studying the scientific feasibility of laser fusion. Inertial confinement fusion with an intense laser has attracted attention as a new future energy source after two oil crises in the 1970s and 1980s. From the beginning, the most challenging physics is known to be the hydrodynamic instability to realize the spherical implosion to achieve more t
Recent work on laser produced plasmas is presented focusing on the theoretical studies of four topics which have been carried out at the Institute of Laser Engineering (ILE), Osaka University, after a brief explanation of the six physics issues to be studied for plasma physics related to the laser fusion. The importance of integrated code development is emphasized and it is shown that the growth of the Rayleigh-Taylor instability at the ablation front is reduced partly due to non-local electron
The turbulent mixing generated at the surface of an inertial-confinement fusion target affected by the Rayleigh-Taylor instability is studied with the use of a simple, nonlinear diffusion model. In order to study the turbulent mixing at the ablation front, a reduced growth rate of the Rayleigh-Taylor instability is used in the model. It is found that, compared with the classical layered fluids, turbulent mixing at the ablation front is significantly suppressed because of the ablative stabilizati
Magnetic fields are ubiquitous in universe, space, and laboratory plasmas. Especially, self-generated magnetic fields are important to know the mind of nature. The formation of Weibel-mediated collisionless shock is studied theoretically as a structure formation by the linear plasma wave growth, nonlinear saturation, and mode–mode coupling. Following a series of computer simulations and experimental studies of the physics, a simple model equation is proposed here to describe the time evolution o
The author reviews fusion science and its extension to astrophysics in the field of theory and computation by picking up five topics. The first is the ablative stabilization of a Rayleigh–Taylor instability at an ablation front and its dispersion relation, the so-called Takabe formula. This formula gives a principal guideline for stable target design and is also applied to studying the turbulent combustion wave in Type Ia supernova explosions. The second is the development of the integrated code
This open access book explains fluid dynamics models and presented hydrodynamic simulations with examples to study 3D evolution of such plasmas.
Generation of strong electrostatic field due to hot electron penetration is studied in the transport region of a laser produced plasma. Assuming a stationary state, the system with collisionless hot electrons governed by Vlasov equation and cold electrons described by the fluid equations is treated. It is found that the generation of localized ion wave turbulence causes strong electric field in the vicinity of the critical layer through its anomalous friction on the return current, and the poten
