Andreas M. Holm

Optical diagnostic design for measuring the radiation front with a mid-leg pumped divertor on DIII-D

G. Ronchi, Robert S. Wilcox, Jonathan H. Yu, Andreas M. Holm et autres

The design of an optical diagnostic system to localize the radiation front in a mid-leg pumped divertor configuration on DIII-D is presented. Divertor detachment is a key mechanism for handling power exhaust in tokamaks, and mid-leg pumping offers a promising approach to …

us (code pays fourni par la source)

Vacuum Neutral Transport Model in UEDGE for Tokamak Far Scrape‐Off Layer

Menglong Zhao, George Wilkie, Andreas M. Holm, Jasmine K. Jaura et autres

ABSTRACT A model for neutral transport in the far scrape‐off layer (SOL) vacuum region (vacuum neutral model) has been developed and implemented in UEDGE. Free‐streaming neutral trajectories between the outermost UEDGE boundary and the vessel wall are preprocessed using DEGAS2 to construct …

us (code pays fourni par la source)

Design of a closed divertor with mid-leg pumping for core-edge integration in DIII-D

Robert S. Wilcox, Jonathan H. Yu, Andreas M. Holm, M.W. Shafer et autres

us, fi (code pays fourni par la source)

Modeling a divertor with mid-leg pumping for high-power H-mode scenariosin DIII-D considering E × B drift flows

Andreas M. Holm

Edge-plasma simulations of a baffled, long-legged divertor in DIII-D, performed using the multi-fluid code UEDGE, indicate that the position of the detachment front is constrained to the location of the pump duct along the low-field side (LFS) baffle.Simulations including magnetic and 𝐄 …

us (code pays fourni par la source)

The effect of divertor closure on the impurity stagnation point in detached L-mode discharges on DIII-D

M.G. Burke, F. Scotti, Steve L. Allen, William H. Meyer et autres

This paper presents experimental measurements of the location of the impurity flow stagnation point in the scrape-off-layer (SOL) of a tokamak plasma. Coherence imaging of carbon-2+ emission (465 nm) is used to track the main-chamber impurity velocity of DIII-D L-mode plasmas with …

Addressing the impact of Lyman opacity in inference of divertor plasma conditions with 2D spectroscopic camera analysis of Balmer emission during detachment in JET L-mode plasmas

J. Karhunen, B. Lomanowski, S. Aleiferis, Pedro J. Carvalho et autres

The impact of re-absorption of the deuterium Lyman series emission was addressed in inferring divertor plasma conditions from Balmer series emission with 2D spectroscopic camera analysis during detachment in JET L-mode plasmas. The previously presented methodology was amended by modifying the standard …

fi, us, gb (code pays fourni par la source)

Simulations of divertor designs that spatially separate power and particle exhaust using mid-leg divertor particle pumping

Jonathan H. Yu, Robert S. Wilcox, R. Maurizio, Andreas M. Holm et autres

• Simulations show that a particle pump located mid-leg on the divertor LFS baffle enhances power dissipation and detachment front stability. • Divertor neutral particle density increases by two orders of magnitude using a mid-leg particle pump compared to a pump located …

us, fi (code pays fourni par la source)

2D analysis of tokamak divertor-plasma detachment-bifurcation with operational parameters and geometries

Menglong Zhao, F. Scotti, T.D. Rognlien, A.G. McLean et autres

UEDGE simulations with density scans for various input power, transport coefficients and outer poloidal leg length are performed to study the conditions for the existence of a bifurcation-like drop of T e at the outer strike point, commonly referred to as a …

us (code pays fourni par la source)

Modeling a divertor with mid-leg pumping for high-power H-mode scenarios in DIII-D considering E × B drift flows

Andreas M. Holm, Robert S. Wilcox, Jonathan H. Yu, T.D. Rognlien et autres

Edge-plasma simulations of a baffled, long-legged divertor in DIII-D, performed using the multi-fluid code UEDGE, indicate that the position of the detachment front is constrained to the location of the pump duct along the low-field side (LFS) baffle. Simulations including magnetic and …

us, fi (code pays fourni par la source)

Understanding the L-H isotope effect at the DIII-D tokamak and advancements in synthetic turbulence diagnostics

Lothar Schmitz, Quinn Pratt, Troy A. Carter, Guiding Wang et autres

Abstract It is determined that while heat flux differences between hydrogen and deuterium isotope experiments result from natural differences in carbon impurity content at DIII-D, it is not the origin of the low to high confinement mode (L-H) transition isotope effect. More …

us, au (code pays fourni par la source)

DIII-D research to provide solutions for ITER and fusion energy

C. T. Holcomb, Joseph Abbate, Alfredo Abe, A. Abrams et autres

Abstract The DIII-D tokamak has elucidated crucial physics and developed projectable solutions for ITER and fusion power plants in the key areas of core performance, boundary heat and particle transport, and integrated scenario operation, with closing the core-edge integration knowledge gap being …

us, no, jp, de, gb, nl, fr, cn, kr (code pays fourni par la source)

Impact of vibrationally and electronically excited H 2 on the molecular assisted recombination rate in detached plasma regimes

R. Chandra, Andreas M. Holm, Mathias Groth

The vibrational redistribution of H2 molecules via the B1Σu+ and C1Πu states are included in the determination of molecular assisted recombination (MAR) rates and are found to have negligible impact in detached plasma regimes. In high recycling and detached divertor plasma conditions, …

fi (code pays fourni par la source)