水平管降膜蒸发换热特性的模拟研究

Horizontal tube falling film evaporators are widely used in seawater desalination and petrochemical industry. A two-dimensional numerical model is established which uses CFD software and UDF program to simulate heat and mass transfer process, and the heat transfer coefficient results are validated by experimental data. It is confirmed that the heat transfer coefficient increases with the larger Reynolds number and saturation temperature. The maximum wall shear force appears between 105 and 120 degrees. When the value of Reynolds number increases from 1000 to 2000, there is an increment of 9.8% and 6.3% of average heat transfer coefficient and maximum wall shear stress, respectively. Besides, average heat transfer coefficient has an increase of 8.3% as the saturation temperature range from 323.15 K to 363.15 K, and maximum wall shear stress decreases by about 25.7%.