  The non-modal self-heating mechanism driven by the velocity shear in
kinematically complex magnetohydrodynamic (MHD) plasma flows is considered. The
study is based on the full set of MHD equations including dissipative terms.
The equations are linearized and unstable modes in the flow are looked for. Two
different cases are specified and studied: (a) the instability related to an
exponential evolution of the wave vector; and (b) the parametric instability,
which takes place when the components of the wave vector evolve in time
periodically. By examining the dissipative terms, it is shown that the
self-heating rate provided by viscous damping is of the same order of magnitude
as that due to the magnetic resistivity. It is found that the heating
efficiency of the exponential instability is higher than that of the parametric
instability.
