자료유형  

 학위논문

Control Number  

0017160620

International Standard Book Number  

9798381971910

Dewey Decimal Classification Number  

530

Main Entry-Personal Name  

Qin, Xijie.

Publication, Distribution, etc. (Imprint  

[S.l.] : The University of Wisconsin - Madison., 2024

Publication, Distribution, etc. (Imprint  

Ann Arbor : ProQuest Dissertations & Theses, 2024

Physical Description  

141 p.

General Note  

Source: Dissertations Abstracts International, Volume: 85-09, Section: B.

General Note  

Advisor: Geiger, Benedikt.

Dissertation Note  

Thesis (Ph.D.)--The University of Wisconsin - Madison, 2024.

Summary, Etc.  

요약Self-generated toroidal flow due to turbulent Reynolds stress is important in fusion plasmas since rotation and its shear improve confinement and stability. This study reports the first measurement of the turbulent Reynolds stress in fusion-grade plasma cores via correlated density and velocity fluctuations in the DIII-D tokamak. Experiments are conducted with both co- and counter-current Neutral Beam Injection (NBI) to control the net torque input and achieve a near-zero flat rotation profile. Electron Cyclotron Heating (ECH) is applied to alter the ion and electron heat fluxes and therefore the mixture of turbulence modes. High-quality fluctuation measurements are obtained via Beam Emission Spectroscopy (BES) and Ultra-Fast Charge Exchange Recombination Spectroscopy (UF-CHERS). Following the application of ECH, the toroidal rotation reverses from counter-current to co-current direction, and the turbulence instability shifts from dominant electron modes to a mixture of electron and ion modes. Residual stress is extracted from the measured toroidal Reynolds stress, and the resulting intrinsic torque is determined. During the NBI-only stage, the volume-integrated intrinsic torque is nearly zero. Upon the application of ECH, a strong rotation drive is identified at the plasma edge, resulting in a net co-current intrinsic torque of 0.40 ± 0.05 Nm, which is comparable to the −0.75 Nm counter-current NBI torque. The toroidal rotation profiles reconstructed using the inferred intrinsic torques align well with experimental observations, successfully reproducing the rotation changes with the application of ECH. These results provide valuable insights into the relationship between turbulence and plasma rotation, demonstrate convincing consistency with the theory of turbulence-driven intrinsic torque, and support the use of turbulence models to predict rotation profiles for future magnetic fusion facilities like ITER.

Subject Added Entry-Topical Term  

Plasma physics.

Subject Added Entry-Topical Term  

Nuclear engineering.

Subject Added Entry-Topical Term  

Analytical chemistry.

Subject Added Entry-Topical Term  

Fluid mechanics.

Index Term-Uncontrolled  

Fusion plasmas

Index Term-Uncontrolled  

Intrinsic rotation

Index Term-Uncontrolled  

Reynolds stress

Index Term-Uncontrolled  

Tokamak

Index Term-Uncontrolled  

Turbulence

Added Entry-Corporate Name  

The University of Wisconsin - Madison Nuclear Engineering & Engineering Physics

Host Item Entry  

Dissertations Abstracts International. 85-09B.

Electronic Location and Access  

로그인을 한후 보실 수 있는 자료입니다.

Control Number  

joongbu:658585