Modeling with statistical hydrodynamic quantities of mass transfer across gas–liquid interface with Rayleigh convection

Experimental and Numerical Investigation on Interfacial Mass Transfer Mechanism for Rayleigh Convection in Hele-Shaw Cell

“…Taking the RC as a turbulent flow, Guo et al suggested two models to characterize gas–liquid interfacial mass transfer with RC: the surface divergence model, associating surface divergence with the mass transfer; and the small eddy model, using energy dissipation as a model parameter. The surface divergence model and the small eddy model are written as eqs and , respectively. where ν is the kinematic viscosity, ε is the rate of turbulence dissipation, Sc is the Schmidt number, u and w are the interface-tangential velocities, int represents gas–liquid interface, and A 1 and A 2 are model constants.…”

“…The concentration difference driven RC phenomenon and its effects on mass transfer in terms of mixing enhancement have long been recognized and extensively studied. A review on the liquid flow and convective mixing induced by RC can be found in Zhou. , The RC phenomenon in CO 2 storage has also been extensively investigated experimentally, ,− theoretically, − and numerically. ,,,− Fundamental research on the RC phenomenon has been updated in a number of aspects, including the mechanism of onset of convection and characterization of the mixing effect (e.g., wavelength of convective fingers, dissolution flux, and averaged concentration profiles). ,,,,− Several different transport mechanisms in different periods of the RC enhanced dissolution process, including periods of diffusion, early convection, late convection, constant flux, and convective shutdown, were identified and discussed. ,,, Useful scaling laws of onset of the convection, wavelengths of the initial convective instabilities, and Sherwood number for RC were also reported. ,,, …”

“…The numerical method can be seen as a powerful tool to investigate the evolution of convective finger and convective mixing for CO 2 sequestration after onset of convection. ,, However, the reported numerical research on RC was usually performed with two-dimensional computational fluid dynamics simulation, figuring out the finger structures by using the simulated two-dimensional velocity fields. ,, Moreover, in the traditional numerical investigations on the concentration distribution and mass transfer, the assumption of a saturated concentration of CO 2 in the liquid at the gas–liquid interface was adopted to simplify the model. But, as shown by Faisal et al, such an assumption may lead to significant error by overestimating the CO 2 concentration at the interface.…”

Validation of Simulation and Mass Transfer Coefficient Prediction with Interfacial Convection

“…To circumvent this problem, some hydrodynamic parameters, such as the pseudo-dissipation rate e*, viscous dissipation rate F, and surface divergence, were adopted to predict the mass transfer coefficient k in Rayleigh convection. However, as a result of the low field synergy between the concentration field and the velocity field, discrepancy in synchronization occurs in the prediction correlation using surface divergence, although the adjusted squared correlation coefficient R 2 meets the accuracy requirements [36].…”

“…In order to consider the effect of the concentration field on the mass transfer coefficient, a new parameter, i.e., the pseudodissipation rate of concentration variance (e c ) was proposed by analogy with the pseudo-dissipation rate e* used by Guo et al [36]. The dissipation rate of concentration variance was put forward by Liu et al [37] in the two-equation model for the calculation of Reynolds mass flow flux, Àu i c j .…”