AN INFLUENCE OF FROZEN-IN LAW VIOLATION EFFECTS ON THE TURBULENT EQUIPARTITION IN TOKAMAKS

Analytical investigations and numerical simulations of the influence o f frozen-in law violation effects on the turbulent equipartition (TEP) of plasma density n similar to 1/q through the safety factor q in tok amaks are performed. Namely, the changes of the frozen-in field topolo gy are taken into account due to strong turbulence. The found influenc e leads to flatter than 1/q density and temperature profiles. For a mo derate level of turbulence, another reason for flat equipartition prof iles was found analytically, if turbulent mixing of passing electrons takes place. This possibility arises due to conservation of the helici ty (AB) integral over frozen-in field lines and produces a flat TEP de nsity profile n similar to AB of passing electrons (A is the vector po tential of the magnetic field B). These influences have been tested in numerical experiments and the results were compared with experimental data in tokamaks. So, the numerical scaling of combined TEP profile o f both trapped and passing electrons is n similar to 1/q(0.5-0.6), whi ch is in good agreement with the experiments. (C) 1998 American Instit ute of Physics.