Flash evaporation method for improved desalination and cooling applications: An experimental study

Abstract

The present study involves the experimental analysis of flash evaporation when sudden depressurization is created into a vertical cylindrical tube having a water volume range of 120 to 180 ml. During experiments, low water pool volumes are used to prevent the impact of gravity on the change of saturation temperature. The investigation is carried out by varying the initial water temperature and back pressure of the vacuum tank in the range of 65 to 80 ∘C and 11.32 to 41.32 kPa, respectively. It is observed that the evaporation rate and cooling rate are both enhanced by increasing the initial pool temperature and decreased by increasing the back pressure. It is reported that the evaporation rate is improved by 29.7 % with an increase in initial water temperature of 5 ∘C and decreases by 152 % with an increase in the back pressure of 10 kPa. It is also found that the cooling rate is improved by 21.6 % with an increase in initial water temperature of 5 ∘C and decreased by 59.2 % with an increase of water volume of 30 ml. It is clear from the visualization procedure that the degree of superheat plays a vital role in flash evaporation.