Verification of the Mathematical Model of Steam Film Condensation from a Flowing Steam-Air Mixture on a Bundle Made of Horizontal Tubes

Resumo

A model of steam film condensation from a flowing steam-air mixture on a bundle made of horizontal tubes was described in previous publications. In the model, the bulk flow is simulated using single-phase flow equations, and the condensation is simulated by means of the boundary conditions on the tube surface considering the laminar flow of the condensate film. This model was supplemented with a simplified model to describe irrigation of the lower tubes in the bundle with condensate formed on the upper tubes. The results are presented of the model verification against the published experimental data on condensation on horizontal smooth tubes in a staggered tube bundle at a steam-air mixture pressure of 30 kPa, a forced horizontal flow velocity upstream of the tube bundle between 1.3 and 4 m/s, and an air volume fraction from 0 to 12%. Disagreement between the predicted and the experimental heat-transfer coefficients does not exceed 20% for all considered regimes. The calculations were performed using the ANES CFD-code being developed by the authors.