Abo Bibliothek: Guest

ISSN Online: 2377-424X

International Heat Transfer Conference 12
August, 18-23, 2002, Grenoble, France

Four stages of combined mass and heat transfer during bubble formation and rise in a bubbly absorber

Get access (open in a dialog) DOI: 10.1615/IHTC12.2440
6 pages

Abstrakt

We studied nonisothermal absorption of a solvable gas from growing at an orifice and rising bubbles when the concentration level of the absorbate in the absorbent is finite (finite dilution of absorbate approximation). Coupled thermal effects during absorption and absorbate concentration level effect on the rate of mass transfer are investigated. Solutions of generalized equations of nonstationary convective diffusion and energy describing coupled mass and heat transfer at all stages of bubble growth and rise are obtained in exact analytical form. Using a general solution the asymptotic solutions for stages of bubble growth, bubble rise with acceleration and bubble rise with a constant velocity are derived. It is shown that for positive dimensionless heat of absorption K thermal effects cause the increase of the mass transfer rate in comparison with the isothermal case. On the contrary, for negative K thermal effects cause the decrease of the mass transfer rate in comparison with the isothermal case. The latter effect becomes more pronounced with the increase of the concentration level of the absorbate in the absorbent. Theoretical results are consistent with experiments of Terasaka et al. (1999) where mass transfer rate during SO2 bubble formation at an orifice submerged in water was measured.