Abstract: In this paper the interphase mixing is studied by the interphase coupling concept. The droplet trijectories are traced using Lagrangian coordinates while the flow field of gaseous phase is treated in Eulerian coordinates. The difference equations of gaseous field are solved by means of the so-called "SIMPLE'' method. Two-phase flow fields with various inlet conditions of the gas flow field and initial conditions of the fuel droplet are calculated. Comparisons between predictions and test results are given.