Effects of E_r/RB_θ profiles on transport reduction in DIII-D and TFTR

A possible relation between the E × B flow curvature and the reduction of electron thermal diffusivity is discussed. We show that unlike the E × B flow shear, the E × B flow curvature has no universal effects on the evolution of the two-point correlation function. Since various instabilities respond differently to the E × B flow curvature, we can gain useful insights into the nature of the ambient turbulence responsible for the electron thermal transport by examining the E_r/RB_θ profiles. Initial results from DIII-D and TFTR are discussed.