Investigation of Hot Gas Mixture Free Jet

Abstract

AbstractThe analysis of individual species of a hot gas mixture in a free jet distribution, is based on the vector form of the continuity equation, including the diffusion member, and on the momentum equation. The measured distributions of temperature and axial velocity in cross-sections of the free jet, together with thermodynamic and transport properties of working gas are used in a designed process of calculation. By means of approximation of temperature and velocity radial profiles by Gaussian functions, the two-dimensional problem is transformed into the one-dimensional task. The designed method is applied on the cold region of the jet generated by a hybrid water stabilised plasma torch with argon gas added into the chamber. In this cold region (T<2500 K), rather precise measurement of temperature and velocity can be carried out using rather simple methods (thermocouples, cooled Pitot tube). By the derived mathematical-physical model, the distribution of mass fractions of individual species of the working gas mixture is computed, and the influence of velocity component and turbulence on this distribution is studied. During the calculation, axial dependencies of crosssection, axial velocity, and the turbulence coefficient in the free jet are obtained.