Numerical simulation of low liquid flow in a mixer consisting of two centrifugal swirlers

The paper describes a procedure of numerical simulation of operating fluid (water) discharge into the air environment through the hydraulic paths of a mixer composed of two low-flow coaxial swirl injectors. The method is based on a two-velocity model of a two-phase liquid flow and determining the interface interaction resistance coefficient versus the Reynolds number in the course of solution. The Reynolds number is calculated from the relative velocity of the liquid components forming the two-phase flow. The paper investigates variations in the mixer spray pattern versus two characteristic dimensions reckoned among the key parameters to calculate the coefficient of interface interaction resistance. Algorithms of calculating the coefficient of interface interaction resistance are proposed. The results of modeling liquid mixing and film flow breakdown within and beyond the mixer hydraulic paths for different values of the characteristic dimensions are presented. It is shown that we can achieve the conformity of the calculation results obtained by using the proposed method with the cold flow data by selecting the values of characteristic dimensions with reference to which interface interaction resistance coefficients are determined. Further works are projected.