Momentum studies with sources and sinks in fusion

Recent experimental [1,2] as well as numerical [3] studies have started emphasising on the possible non-neoclassical behaviour of poloidal momentum. Correlation between this observed non-neoclassical behaviour and turbulence-induced Reynolds stresses was pointed out in the latter work. Building upon those results, a discussion of the mechanisms through which microturbulence may drive poloidal flows has been proposed [4]. More generally, the role of turbulence in determining rotation profiles and momentum transport is paramount, as exemplified through the chief role of turbulence-induced mean profile dynamics in flux-driven gyrokinetic simulations, including versatile momentum sources. Poloidal and parallel momentum are investigated, as well as their respective transport, in both L--mode-like and enhanced confinement regimes.\\[4pt] [1] K. H. Burrell et al., Phys. Plasmas \textbf{1}:1536 (1994)\\[0pt] [2] K. Cromb\'e et al., Phys. Rev. Lett. \textbf{95}:155003 (2005)\\[0pt] [3] G. Dif-Pradalier et al., Phys. Rev. Lett. \textbf{103}:065002 (2009)\\[0pt] [4] C.J. McDevitt et al., this conference