Simulating evaporation

Evaporation in a closed system

A liquid in a closed system will not start to evaporate until its boiling point is reached. Further evaporation will occur when the temperature increases. Therefore, the fastest way to simulate evaporation is using a Temperature survey. We will use Standard Seawater to present this method.

• Add a single point calculation
• Change the calculation type to Vapor Fraction
• Set the vapor fraction to 1% and calculate. This will determine the initial boiling point

• Set the vapor fraction to 99% less the % of dissolved solids (seawater for example contains about 3.6% solids). If the calculation fails, then lower the vapor fraction until it converges. This sets the dryness temperature

• Add a Survey calculation - Use the default Temperature survey
• Set the initial and final temperatures to the values obtained above. Add sufficient increments (e.g., 10-20) so that the plot has good resolution.
• Plot the liquid volume vs. temperature first. See if sufficient liquid evaporated for your case.