Abstract
The permeability of poly-dimethyl-siloxane (PDMS) to CO_2 focused on distance between gas and liquid channels was experimentally investigated utilizing simultaneous measurement of liquid velocity and pH distribution via micro-PTV/LIF method. CO_2 concentration was calculated from pH considering the chemical equilibration in water. CO_2 penetrated into PDMS and dissolved into the liquid flow quickly when the gas flow rate was raised or the gas passed through a thinner PDMS wall. It was found that large convection flux of CO_2 in water was induced near the wall by the non-slip condition and the high concentration gradient.
