@article{7514, author = {H. Weisen and Y. Camenen and A. Salmi and T. W. Versloot and P. C. de Vries and M. Maslov and T. Tala and M. Beurskens and C. Giroud and JET-EFDA Contributors}, title = {Ubiquity of non-diffusive momentum transport in JET H-modes}, abstract = {A broad survey of the experimental database of neutral beam heated baseline H-modes and hybrid scenarios in the JET tokamak has established the ubiquity of non-diffusive momentum transport mechanisms in rotating plasmas. As a result of their presence, the normalized angular frequency gradient R ∇ ω / ω is higher than expected from momentum diffusion alone, by about unity in the core ( r / a ∼ 0.3), rising to near 5 close to the edge, where its contribution to the total gradient is comparable to the gradient associated with the diffusive flux. The magnitude and parameter dependences of the non-diffusive contribution to the gradient are consistent with a theoretically expected pinch, which has its origin in the vertical particle drift resulting from the Coriolis force. Linear gyrokinetic calculations of the pinch number RV / χ φ and the Prandtl number χ φ / χ i are in good agreement with the experimental observations, with similar dependences on R / L n , q and ε = r / R . A contribution due to residual stresses may also be present, but could not be identified with certainty.}, year = {2012}, journal = {Nuclear Fusion}, volume = {52}, number = {11}, pages = {114024}, url = {http://www.iop.org/Jet/article?EFDP11051&EFDP11055}, doi = {10.1088/0029-5515/52/11/114024}, language = {eng}, }