Numerical investigation of the process of low calcarium gas injection in the mixture air heater

Abstract

Gas mixing air heaters are widely used for heating air in the systems of inflow ventilation of autonomous air heating and thermal curtains of industrial premises, drying installations, for heating of greenhouse farms. Mixing of air with products of combustion of gaseous fuel provides effective air heating. Air heaters are manufactured with a nominal thermal capacity of 0.15 to 6.3 MW. The coefficient of working regulation for thermal power, not less than 2,5. Air heating in the range of 30-80 ° C. The mathematical modeling of radiation - convective heat transfer in the gas tract of the boiler is executed on the basis of the averaged by the Reynolds number of the Navie - Stoks equations, taking into account gravity and with the neglect of compression. The model consists of the equation of continuity, impulse transfer, energy and chemical components of the gas mixture, recorded in a stationary form. The equations are closed by Newton's law for a pressure sensor.Fourier law for heat flux, the Fick's law for mass flow, the Clapeyron-Mendeleev law for the thermodynamic state of a gas mixture, the equations of the turbulence model k-ε Launder-Spalding and the model of turbulent combustion of Magnus-Hertgaher. The results of numerical simulation in the form of vectors of flow rates of gases, temperature, and concentration of O2, CH4, CO, H2O, CO2 in the characteristic sections of the flow part are presented. The aerodynamic structure of the torch, long range and maximum temperature zone are determined.The obtained results of theoretical research can be used to regulate the design parameters of gas mixing air heaters with the provision of specified concentrations of these gases depending on their need for growing crops in closed soils, as well as to achieve the necessary temperatures and velocities of the gases of the corresponding technologies. Maybe the basis for algorithmization of automation of the corresponding technological processes and cycles of elements of air (gas) systems of heat supply for various purposes. Calorie gas in mixing air heaters are presented