Zobrazeno 1 - 10
of 495
pro vyhledávání: '"Highcock, E."'
Autor:
van Wyk, F., Highcock, E. G., Field, A. R., Roach, C. M., Schekochihin, A. A., Parra, F. I., Dorland, W.
We investigate the effect of varying the ion temperature gradient (ITG) and toroidal equilibrium scale sheared flow on ion-scale turbulence in the outer core of MAST by means of local gyrokinetic simulations. We show that nonlinear simulations reprod
Externí odkaz:
http://arxiv.org/abs/1704.02830
Autor:
Kirk, A, Adamek, J, Akers, RJ, Allan, S, Appel, L, Lucini, F Arese, Barnes, M, Barrett, T, Ayed, N Ben, Boeglin, W, Bradley, J, Browning, P K, Brunner, J, Cahyna, P, Carr, M, Casson, F, Cecconello, M, Challis, C, Chapman, IT, Chapman, S, Conroy, S, Conway, N, Cooper, WA, Cox, M, Crocker, N, Crowley, B, Cardnell, S, Chorley, J, Cunningham, G, Danilov, A, Darrow, D, Dendy, R, Dickinson, D, Dorland, W, Dudson, B, Easy, L, Elmore, S, Evans, M, Farley, T, Fedorczak, N, Field, A, Fitzgerald, I, Fox, M, Freethy, S, Garzotti, L, Ghim, YC, Gi, K, Gorelenkova, M, Gracias, W, Gurl, C, Guttenfelder, W, Ham, C, Harting, D, Havlickova, E, Hawkes, N, Hender, T, Henderson, S, Hillesheim, J, Hnat, B, Horacek, J, Howard, J, Howell, D, Dunai, D, Fishpool, G, Gibson, K, Harrison, J, Highcock, E, Huang, B, Inomoto, M, Imazawa, R, Jones, O, Kadowaki, K, Kaye, S, Keeling, D, Kocan, M, Kogan, L, Komm, M, Lai, W, Leddy, J, Leggate, H, Imada, K, Klimek, I, Hollocombe, J, Lipschultz, B, Lisgo, S, Liu, YQ, Lloyd, B, Lomanowski, B, Lukin, V, Maddison, G, Madsen, J, Mailloux, J, Martin, R, McArdle, G, Lupelli, I, McClements, K, McMillan, B, Meakins, A, Meyer, H, Michael, C, Militello, F, Milnes, J, Motojima, G, Muir, D, Naylor, G, Nielsen, A, O'Brien, M, O'Mullane, M, Olsen, J, Omotani, J, Ono, Y, Pamela, S, Morris, AW, O'Gorman, T, Pangione, L, Parra, F, Patel, A, Peebles, W, Perez, R, Pinches, S, Piron, L, Price, M, Reinke, M, Ricci, P, Riva, F, Roach, C, Romanelli, M, Ryan, D, Saarelma, S, Saveliev, A, Scannell, R, Schekochihin, A, Sharapov, S, Sharples, R, Shevchenko, V, Shinohara, K, Silburn, S, Simpson, J, Stanier, A, Storrs, J, Summers, H, Takase, Y, Tamain, P, Tanabe, H, Tanaka, H, Tani, K, Taylor, D, Thomas, D, Thomas-Davies, N, Thornton, A, Turnyanskiy, M, Valovic, M, Vann, R, Van Wyk, F, Walkden, N, Watanabe, T, Wilson, H, Wischmeier, M, Yamada, T, Young, J, Zoletnik, S, Team, the MAST, Team, the EUROfusion MST1
New results from MAST are presented that focus on validating models in order to extrapolate to future devices. Measurements during start-up experiments have shown how the bulk ion temperature rise scales with the square of the reconnecting field. Dur
Externí odkaz:
http://arxiv.org/abs/1611.06047
The confinement of heat in the core of a magnetic fusion reactor is optimised using a multidimensional optimisation algorithm. For the first time in such a study, the loss of heat due to turbulence is modelled at every stage using first-principles no
Externí odkaz:
http://arxiv.org/abs/1608.08812
Publikováno v:
Journal of Plasma Physics, 82(6), 905820609 (2016)
Tokamak turbulence, driven by the ion-temperature gradient and occurring in the presence of flow shear, is investigated by means of local, ion-scale, electrostatic gyrokinetic simulations (with both kinetic ions and electrons) of the conditions in th
Externí odkaz:
http://arxiv.org/abs/1607.08173
Publikováno v:
Phys. Plasmas 23, 070703 (2016)
Transfer of free energy from large to small velocity-space scales by phase mixing leads to Landau damping in a linear plasma. In a turbulent drift-kinetic plasma, this transfer is statistically nearly canceled by an inverse transfer from small to lar
Externí odkaz:
http://arxiv.org/abs/1603.06968
Autor:
Schekochihin, A. A., Parker, J. T., Highcock, E. G., Dellar, P. J., Dorland, W., Hammett, G. W.
Publikováno v:
Journal of Plasma Physics 82, 905820212 (2016)
A scaling theory of long-wavelength electrostatic turbulence in a magnetised, weakly collisional plasma (e.g., ITG turbulence) is proposed, with account taken both of the nonlinear advection of the perturbed particle distribution by fluctuating ExB f
Externí odkaz:
http://arxiv.org/abs/1508.05988
Autor:
Ghim, Y. -c., Field, A. R., Schekochihin, A. A., Highcock, E. G., Michael, C., Team, the MAST
Experimental data from the Mega Amp Spherical Tokamak (MAST) is used to show that the inverse gradient scale length of the ion temperature R/LTi (normalized to the major radius R) has its strongest local correlation with the rotational shear and the
Externí odkaz:
http://arxiv.org/abs/1211.2883
Autor:
Highcock, E. G.
The transport of heat that results from turbulence is a major factor limiting the temperature gradient, and thus the performance, of fusion devices. We use nonlinear simulations to show that a toroidal equilibrium scale sheared flow can completely su
Externí odkaz:
http://arxiv.org/abs/1207.4419
Autor:
Highcock, E. G., Schekochihin, A. A., Cowley, S. C., Barnes, M., Parra, F. I., Roach, C. M., Dorland, W.
Sheared toroidal flows can cause bifurcations to zero-turbulent-transport states in tokamak plasmas. The maximum temperature gradients that can be reached are limited by subcritical turbulence driven by the parallel velocity gradient. Here it is show
Externí odkaz:
http://arxiv.org/abs/1203.6455
Publikováno v:
PPCF 54, 055011 (2012)
Differential rotation is known to suppress linear instabilities in fusion plasmas. However, even in the absence of growing eigenmodes, subcritical fluctuations that grow transiently can lead to sustained turbulence. Here transient growth of electrost
Externí odkaz:
http://arxiv.org/abs/1111.4929