Thermodynamics of nonequilibrium processes in a tornado: synergistic   approach
  In the mathematical modeling of strongly nonequilibrium and nonlinear processes in a tornado approach based on the momentum transfer equations with a model function of sources and sinks is used, which puts this approach to the sharpening problems, where the maximum velocity distribution over the space of indefinitely growing for a limited time. Nonlinear momentum source in the medium leads to a blow-up regime, and the development of the regime, itself generated by a nonlinear medium, leads to self-organization, which is described by numerical methods. In this case, the competition between processes of the increasing due to nonlinear source and pulse propagation taking into account the viscosity of the medium leads to the appearance of new medium characteristic - some linear size - the spatial diameter of the tornado, on which these processes "balance" each other. The approach allows to obtain equations that describe the physical effects observed and explain nonlinear transfer mechanisms of layering momentum in a tornado, determining the speeds and pressure gradients for nonpotential flow, as well as each altitude local layer thermodynamic properties - entropy production, entropy change rate and free energy. We describe the spatial and velocity characteristics of tornado various intensities, speed components in the tornado core and its surroundings, the emergence of spiral waves, rising to a arm height, the appearance of spatial ring (thrombus) and mesovortexes outside. 
G. P. Bystrai, I. A. Lykov, S. A. Okhotnikov
physics.ao-ph