ИСТИНА

Development of the full Lagrangian approach1 is presented to study evolution of passive scalar gradients in different gas and fluid flows. The passive scalar is any physical characteristic that does not affect on the main flow (velocity field). Diffusion transport is not taken into account. Various physical parameters can be regarded as passive scalar gradients, e.g. density heterogeneity in rapid stratified flows, temperature gradients in high Peclet number flows, inertialess particle concentration gradients in disperse flows, gradients of “frozen” vorticity and electric charge, etc. On the base of the approach suggested one can calculate passive scalar gradients with respect to Eulerian coordinates solving ODE along Lagrangian trajectories of fluid particles. In the work several examples are given to illustrate applications of the method.