In fluid field, Bernard  described the equations of motion for six velocity potentials of perfect fluids which led to a variational principle that reproduced the Eulerian equation
It is well known that for any systematic conditioned averaging procedure the mean value of any scalar derivative appearing in an instantaneous Eulerian equation is transformed into a derivative of the scalar averaged mean value, plus an extra interface source term.
Despite the consolidation of some of the above mentioned approaches, the appropriate theoretical technique to generate useful exact continuous phase Eulerian equations to deal with general Two-Phase Flow is nowadays far from being a closed subject.
DYTRAN software package is used as the solver, enabling solving Lagrangian and Eulerian equations
Coverage includes (for example) Eulerian equations
of hydrodynamics, Navier- Stokes equations, stellar structure equations, and equations of radiation hydrodynamics.