ISSN Online: 2688-7231
ISBN Online: 978-1-56700-524-0
Proceedings of the 26thNational and 4th International ISHMT-ASTFE Heat and Mass Transfer Conference December 17-20, 2021, IIT Madras, Chennai-600036, Tamil Nadu, India
Influence of Internal Circulation on Absorption of Atmospheric CO2 and SO2 in Rain Drop
Motion of dispersed liquid drops in an immiscible fluid can cause circulatory motion within the drop, due to shear forces at the interface. This internal circulation can enhance the rate of mass transfer through the interface. Removal of CO2 and SO2 present in atmosphere by absorption in falling rain drops under isothermal conditions was studied numerically using a Computational Fluid Dynamics (CFD) simulation tool, ANSYS FLUENT. Influence of internal circulation on rate of absorption was studied by considering water drops of 1 mm and 0.5 mm falling in air. Mass transfer resistance in air was neglected and interface concentration was obtained by using Henry's law. The evolution of mass fraction is observed to be similar for both CO2 and SO2. Absorption of SO2 is slower than that of CO2 in spite of higher interface concentration of CO2. Reduction in time taken for absorption by halving the drop size is slightly more than what is expected, which may be due to the reduced internal circulation associated with smaller drops.