Method and Algorithm for Calculating Isobaric and Nonisobaric Three-Dimensional Turbulent Jets of Reacting Gases

Abstract

This paper presents a calculation method and algorithm, as well as numerical results of studying chemically reacting turbulent jets based on three-dimensional parabolic systems of Navier–Stokes equations for multicomponent gas mixtures. Continuity equations are used to calculate the mass imbalance when solving with constant pressure, and with variable pressures, with the equations of motion and continuity. Diffusion combustion of a propane–butane mixture flowing from a square-shaped nozzle in a submerged flow of an air oxidizer is numerically studied. Pressure variability significantly affects the velocity (temperature) profiles in the initial sections of the jet, and, when moving away from the nozzle exit, the pressure effect can be considered imperceptible, but the plume length is longer than that at constant pressure, but it does not significantly affect the shape of the plume. The saddle-shaped behavior of the longitudinal velocity in the direction of the major axis is numerically obtained for large initial values of the turbulence kinetic energy of the main jet. The presented method allows studying nonreacting and reactive turbulent jets flowing from a rectangular nozzle.