Calculation of turbulent momentum and heat transfer in pipe flow of a gas with variable physical properties

A numerical calculation of heat transfer and resistance, and of turbulent momentum and heat transfer, in a quasisteady flow of a gas with variable physical properties in a round tube is presented. The balance equations for the turbulence energy, turbulent tangential stresses, intensity of radial component of the velocity pulsation, and the turbulent heat flux are used for closure of the averaged equations of motion and energy. The paper gives the results of calculation of the coefficient of turbulent momentum transfer, the turbulent Prandtl number, heat transfer, resistance, mean velocity profile and temperature profile in a flow of air and ammonia during heating and cooling.