Simulation of Heat and Mass Transfer Involving Vapor Condensation in the Presence of Non-Condensable Gases in Plane Channels Available to Purchase

Results from computational fluid dynamics (CFD) simulations of heat and mass transfer involving the condensation of vapor in the presence of non-condensable gases in plane channels are presented. The simulations were carried out using FLUENT^®. Convective heat and mass transfer and vapor condensation at a constant wall temperature were first investigated with the aim of comparing the CFD results with well established correlations. CFD simulations of heat and mass transfer and water vapor condensation in the presence of non-condensable air were then carried out for constant heat transfer coefficients for the condensation wall and coolant with different mass fractions of water vapor and inlet velocities. The predictions obtained from this are compared with experimental data and reasonable agreement has been found for the condensation rates of water vapor and heat flux. Finally, the condensation of the water vapor was simulated in a heat exchanger including both the cooling water and vapor-air mixture channels separated by solid walls. This simulation is close to reality and no assumptions are required for the temperature or heat transfer coefficient at the condensing wall. The difficulties of simultaneously simulating a gas mixture and liquid flowing in separate channels using commercially available CFD software are discussed and strategies to overcome these difficulties are outlined. Preliminary results from this third simulation will also be presented and compared with available experimental results.