1 13 th ITPA Transport Physics Group Meeting Naka, 1-3 October 2007 V. Mukhovatov ITER Rotation Issues

13 th ITPA Transport Physics Group Meeting, 1-3 October 2007, Naka, Japan 2 Plasma Rotation Plasma rotation important for nearly all ITER plasma characteristics  Energy confinement  NTM stability  RWM stability  Disruptivity Usual approach at present:  Neglect intrinsic rotation  NBI momentum input with   =  

13 th ITPA Transport Physics Group Meeting, 1-3 October 2007, Naka, Japan 3 Three Major Recent Advances Scaling for intrinsic rotation – J.Rice Demonstration of additivity of NBI induced rotation and intrinsic rotation – DIII-D Demonstration of low rotation required for RWM stability at low error field – DIII-D and JT-60U All three are favourable for ITER!

13 th ITPA Transport Physics Group Meeting, 1-3 October 2007, Naka, Japan 4 A.Polevoi et al Nucl. Fusion 45 (2005) 1451 Plasma Rotation in ITER at   =  i ASTRA Code Predictions Inductive modeImproved Hybrid modeSteady State mode HH98(y,2) = 1HH98(y,2) = 1.2HH98(y,2) = 1.31 P NB =33MWP NB =33MWP NB =33MW P RF =7MWP ECCD =34.5MW Inductive: f tor (0) = 1 kHz Steady state: f tor (0) = 3.4 kHz

13 th ITPA Transport Physics Group Meeting, 1-3 October 2007, Naka, Japan May 2007 J. Rice, 12 th TP ITPA Meeting, Lausanne, 7-10 May 2007 f tor ~ 9 kHz f tor ~ 4 kHz ITER

13 th ITPA Transport Physics Group Meeting, 1-3 October 2007, Naka, Japan 6 Intrinsic Rotation in ITER Rice scaling predicts 3-4 times higher rotation rate in ITER compared to that expected from planned two NB injectors (16.5MW/1MeV each) Predicted intrinsic rotation is equivalent to torque produced by seven additional ITER- like injectors with total power above 100 MW

13 th ITPA Transport Physics Group Meeting, 1-3 October 2007, Naka, Japan 7 Intrinsic Rotation in ITER: Uncertainty Uncertainties in predicted intrinsic rotation for ITER are, however, quite large To reduce the uncertainty additional experiments, guidelines from first-principle theory and theory-based simulations are required Re-analysis of available data assuming   /  i = 1 for NBI induced rotation and considering extra rotation as intrinsic one may be useful

13 th ITPA Transport Physics Group Meeting, 1-3 October 2007, Naka, Japan 8 Comparison of Momentum and Ion Thermal Diffusivities in NB only Heated Plasma D. Nishijima et al Plasma Phys. Control. Fusion 47 (2005) 89 ASDEX Upgrade   <  i manifests on the presence of intrinsic rotation (?)   /  I =

13 th ITPA Transport Physics Group Meeting, 1-3 October 2007, Naka, Japan 9 Energy Confinement Low Effect of ExB Shearing Rate on Plasma Performance in ITER Hybrid Scenario R. Budny and C. Kessel (PPPL) ITPA Saint Petersburg, Russia, October, 2005 Intrinsic rotation neglected

13 th ITPA Transport Physics Group Meeting, 1-3 October 2007, Naka, Japan 10 Effect of Plasma Rotation on NTMs A.M. Popov, 33rd EPS Conference on Plasma Phys. Rome, June 2006 ECA Vol.30I, P (2006) Simulations on NTMs in ITER with nonlinear 3D MHD code NFTC: in the absence of error fields, single 3/2 mode is stabilized by rotation In the presence of m/n=1/1 error field, rotation stabilizes 3/2 NTM and destabilises 2/1 NTM

13 th ITPA Transport Physics Group Meeting, 1-3 October 2007, Naka, Japan 11 Summary Assumption   =  i underestimates toriodal rotation rate in ITER Rice scaling predicts intrinsic rotation in ITER several times higher than expected from NBI, although uncertainty is large Additional experiments, guidelines from first principle theories and theory-based simulations are required to improve accuracy of rotation predictions for ITER Structure of intrinsic toroidal rotation, V  (r,  ), is required Rate of intrinsic poloidal rotation is necessary