Coordinate System for the Transport Model

It is assumed that profile information exists on a grid from 0 to jmaxm when the model is called. Gradients are computed with respect to the normalized square root of the toroidal flux with where is the toroidal flux, B_T is the toroidal field, and a is the minor radius. For every unstable root in the k_y spectrum, the quasi-linear diffusivities are derived summing over the individual contributions. The effective transport coefficients are in units of m²/s and are defined assuming that the the transport equations take the form prescribed by the ITER Expert Group,

Here, is the effective diffusivity and no distinction is made between convection and conduction.

The toroidal momentum is defined with the momentum diffusion equation given as