Heat transfer analysis of two-phase dispersed swirl flow.

摘要

thermodynamic nonequilibrium model has been developed for a two-phase, vapor and liquid droplet, dispersed swirl flow in a vertical tube with a twisted-tape insert. It takes account of the heat transfer phenomena between two phases, and each phase with solid boundary where a variable heat flux along axial direction is imposed. A numerical method is developed to solve the system of nonlinear differential equations. The local equilibrium conditions of the fluid at the point of critical heat flux (CHF) are chosen as the initial conditions to start the numerical integration to the downstream. Wall temperature, super-heat vapor temperature, heat transfer rate from two phases, and velocity distributions of two phases have been predicted and analyzed, which were then verified by comparing them with the low wall-superheat heat exchanger experimental data of water-steam in the range of 900.0