Calculation of indirect condensation heat transfer
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May I ask, half of the gas is condensed by water, while the other half remains uncondensed. How is this heat exchange process calculated? Thank you for the help
It can be calculated using software. Manual calculation: For calculating the film heat transfer coefficient on the steam side, the total amount of steam is used, and a 50% area margin is applied.
The most important thing is to determine whether the gas that has not been condensed is a non-condensable gas. If it is a certain type of medium, information on it can be found in standard heat exchange textbooks. If it is a non-condensable gas, it is necessary to calculate separately the heat exchange area required for the gas phase and that required for condensation; generally, the heat exchange area needed for cooling the gas phase is much larger than that required for condensation.
There are calculation software available to check; doing it by hand is too troublesome.
Are you referring to the condensation problem involving non-condensable gases? If so, the calculations are quite complex; for manual calculations, you can refer to Method 11.6 for designing cooling condensers on page P145 of the book \"Heat Exchanger Design Manual\" by Hidetaka Ogiba.
For pure substances, the calculations are carried out using the formulas in Chapter 4 of the heat exchanger design manual (by Qian Songwen). For substances containing non-condensable gases, the calculations follow the guidelines provided above. When there is a phase change, the latent heat must be taken into account; in the absence of a phase change, only the sensible heat needs to be considered. It is important to note that the partial pressures corresponding to each component differ