  Till now the magnetohydrodynamic (MHD) simulation of the reversed field pinch
(RFP) has been performed by assuming axis-symmetric radial time independent
dissipation profiles. In helical states this assumption is not correct since
these dissipations should be flux functions, and should exhibit a helical
symmetry as well. Therefore more correct simulations should incorporate
self-consistent dissipation profiles. As a first step in this direction, the
case of uniform dissipation profiles was considered by using the 3D nonlinear
visco-resistive MHD code SpeCyl. It is found that a flattening of the
resistivity profile results in the reduction of the dynamo action, which brings
to marginally-reversed or even non-reversed equilibrium solutions. The physical
origin of this result is discussed in relation to the electrostatic drift
explanation of the RFP dynamo. This sets constraints on the functional choice
of dissipations in future self-consistent simulations.
