Deshko G. Numerical simulation of jet flows of viscous multicomponent chemically reacting gas

The research subject is the motion of a turbulent chemically reacting multicomponent gas mixture through channels and jets. The objective is to develop rational algorithms of the operating computation of stationary jet turbulent non-equilibrium flows, to carry out numerical studies and determine special features of ignition and combustion of hydrocarbon fuels into subsonic and supersonic jets, based on simplified Navier-Stokes models of stationary equations of a narrow channel and viscous layer by the use of effective marshing methods. The research method is a numerical simulation of turbulent non-equilibrium flows, based on simplified Navier-Stokes equations, by the use of marshing methods. The study developed the scientific and methodic support for analyzing the regularities associated with processes of ignition and combustion of gas hydrocarbon jets in air and can be used for enhanced knowlidge about high-temperature non-equilibrium processes of continuum mechanics. Practical importance of the results obtained. The scientific and methodic support provided and special features revealed of non-equilibrium flows can be used to reduce the quantity of experimantal investigations, to interpret the experimental results, to choose initial parameters and optimize various technical devices for machine-building and technological processes for chemical and metallurgical industries, aerospace technology, to develop combustion chambers of ramjet engines, etc. Research novelty. Rational algorithms for determining the longitudinal pressure gradient and the asymptotic jet boundary allowing a reduction of computations for modelling non-equilibrium jet flows in the frame of the narrow channel and the viscous layer are developed. A model of turbulence and a rational kinetic model of combustion of hydrocarbon fuels are selected for numerical studies of turbulent jet flows of chemically reacting gas mixtures. Important regularities of ignition and combustion of a fuel jet in a cocurrent flow are determined for both subsonic and supersonic combustion. Proposals for selecting rational parameters of a non-equilibrium jet gas flow, improving processes of mixing, ignition and propellant burn-out are formulated. Applications: thermal gasdynamic processes through channels, jets and gasdynamic passages of ramjet engines.