Toroidal modeling of thermal particle drift kinetic effects and sub-sonic plasma flow on internal kink mode

The effects of a sheared poloidal flow on the m = 1 (poloidal mode number) and n = 1 (toroidal mode number) kinetic internal kink mode are simulated by the linearized version of the gyro-reduced MHD code, GRM3D-2F, based on a two-field and two-fluid gyro-reduced MHD model, including the kinetic effects of electron inertia and the perturbed electron pressure gradients along the magnetic field. A parameter study for different values of de (collisionless electron skin depth) with a fixed value of ρs = 0 (ion Larmor radius estimated by the electron temperature) shows that the smaller-de case, which has the smaller growth rate, is stabilized by the smaller sheared poloidal flow. When ρs is raised to ρs > de for a fixed value of de, the instability is stabilized by the smaller shear flow compared with the case of ρs < de, although the growth rate without the flow is larger for ρs > de. Since de is very much less than the minor radius, and ρs > de for the existing and future experiments, it is possible that even a quite small sheared poloidal flow may have a crucial influence on the kinetic internal kink mode.

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Verification and validation of linear gyrokinetic and kinetic-MHD simulations for internal kink instability in DIII-D tokamak

Nuclear Fusion ◽

10.1088/1741-4326/ac48a6 ◽

2022 ◽

Author(s):

Guillaume Brochard ◽

Jian Bao ◽

Chang Liu ◽

Nikolai N Gorelenkov ◽

Gyungjin Choi ◽

...

Keyword(s):

Growth Rate ◽

Emission Measurement ◽

Ion Temperature ◽

Ion Temperature Gradient ◽

Kink Mode ◽

Mhd Simulations ◽

Equilibrium Reconstruction ◽

Magnetic Perturbations ◽

Kinetic Effects ◽

Kink Instability

Abstract Verification and linear validation of the internal kink instability in tokamak have been performed for both gyrokinetic (GTC) and kinetic-MHD codes (GAM-solver, M3D-C1-K, NOVA, XTOR-K). Using realistic magnetic geometry and plasma profiles from the same equilibrium reconstruction of the DIII-D shot #141216, these codes exhibit excellent agreement for the growth rate and mode structure of the internal kink mode when all kinetic effects are suppressed. The simulated radial mode structures, obtained from linear simulations, are in reasonable agreement with the normalised electron cyclotron emission measurement after adjusting, within the experimental uncertainty, the safety factor q=1 flux-surface location in the equilibrium reconstruction. Compressible magnetic perturbations strongly destabilize the kink, while poloidal variations of the equilibrium current density reduce the growth rate of the kink. Furthermore, kinetic effects of thermal ions are found to decrease the kink growth rate in kinetic-MHD simulations, but increase the kink growth rate in gyrokinetic simulations, due to the additional drive of the ion temperature gradient and parallel electric field. Kinetic thermal electrons are found to have negligible effects on the internal kink instability.

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Intrinsic kinetic effects during martensitic transformations

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2003850 ◽

2003 ◽

Vol 112 ◽

pp. 133-137 ◽

Cited By ~ 1

Author(s):

A. Fraile-Rodriguez ◽

P. P. Rodriguez ◽

R. B. Pérez-Saez ◽

A. Lopez-Echarri ◽

J. San Juan

Keyword(s):

Martensitic Transformations ◽

Kinetic Effects ◽

Intrinsic Kinetic

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OPTIMISATION OF THE CHARACTERISTICS OF THE PLASMA FLOW FROM A DIELECTRIC CHAMBER

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19797172 ◽

1979 ◽

Vol 40 (C7) ◽

pp. C7-349-C7-350

Author(s):

I. I. Egorov ◽

L. N. Lesnevsky ◽

G. A. Popov ◽

A. G. Sobol ◽

V. N. Turin

Keyword(s):

Plasma Flow

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Clinical Renal Function Testing by External Double Isotope Monitoring Technique

Nuklearmedizin ◽

10.1055/s-0038-1624730 ◽

1971 ◽

Vol 10 (01) ◽

pp. 16-24

Author(s):

J. Fog Pedersen ◽

M. Fog Pedersen ◽

Paul Madsen

Keyword(s):

Renal Function ◽

Glomerular Filtration Rate ◽

Glomerular Filtration ◽

Plasma Flow ◽

Filtration Rate ◽

Renal Plasma Flow ◽

Correlation Coefficients ◽

Feedback System ◽

Effective Renal Plasma Flow ◽

Advantages And Disadvantages

SummaryAn accurate catheter-free technique for clinical determination simultaneouslyof glomerular filtration rate and effective renal plasma flow by means of radioisotopes has been developed. The renal function is estimated by the amount of radioisotopes necessary to maintain a constant concentration in the patient’s blood. The infusion pumps are steered by a feedback system, the pumps being automatically turned on when the radiation measured over the patient’s head falls below a certain preset level and turned off when this level is again readied. 131I-iodopyracet was used for the estimation of effective renal plasma flow and125I-iothalamate estimation of the glomerular filtration rate. These clearances were compared to the conventional bladder clearances and good correlation was found between these two clearance methods (correlation coefficients 0.97 and.90 respectively). The advantages and disadvantages of this new clearance technique are discussed.

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RENAL FUNCTION AND KIDNEY SIZE FOLLOWING HYPOPHYSECTOMY IN MAN

Acta Endocrinologica ◽

10.1530/acta.0.0480348 ◽

1965 ◽

Vol 48 (3) ◽

pp. 348-354 ◽

Cited By ~ 33

Author(s):

Thomas Falkheden ◽

Ingmar Wickbom

Keyword(s):

Renal Function ◽

Diabetic Retinopathy ◽

Glomerular Filtration Rate ◽

Plasma Flow ◽

Mammary Carcinoma ◽

Filtration Rate ◽

Renal Plasma Flow ◽

Kidney Weight ◽

Kidney Size ◽

Before And After

ABSTRACT Measurements of glomerular filtration rate (GFR) and renal plasma flow (RPF) were performed in close connection with roentgenographic estimation of kidney size, before and after hypophysectomy, in 10 patients (four cases of metastatic mammary carcinoma, five cases of diabetic retinopathy and one case of acromegaly). Hypophysectomy was regularly followed by a decrease in GFR and RPF. In most cases, a reduction in the roentgenographic kidney size was also observed. However, the changes in the roentgenographic kidney size and calculated kidney weight after hypophysectomy were smaller and occurred at a slower rate than the alterations in GFR and RPF. The results favour the view that, primarily, the decrease in GFR and RPF following hypophysectomy is essentially functional rather than due to a reduced kidney mass.

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