Water flooding coefficient

The volume factor Rv [45,46] and the water flooding coefficient pv [52] reflect the amount of liquid carried away by the foam during foam separation... 

The water flooding coefficient is related to the volume factor (Ry) by the relation [51 ]... 

For the process of foam accumulation involving capillary drying, an equation relating the water flooding coefficient to the structural parameters of the foam can be derived [67]. 

It can be seen from Eq. (10.45) that only two of the three characteristics of the adsorption accumulation are independent. For instance, at different accumulation ratios, the same degree of extraction can be achieved by the appropriate variations of the water flooding coefficient. 

The resistance of oxygen in catalyst layer R i R g varies with different degree of water flood, which indeed influence the diffusion coefficient. However, this effect on the cell voltage is relatively small. Due to the fact that the resistance caused by membrane fraction in the void region of the catalyst layer is so high, the added resistance caused by liquid water is nearly negligible. 

The EOD coefficient, is the ratio of the water flux through the membrane to the proton flux in the absence of a water concentration gradient. As r/d,3g increases with increasing current density during PEMFC operation, the level of dehydration increases at the anode and normally exceeds the ability of the PEM to use back diffusion to the anode to achieve balanced water content in the membrane. In addition, accumulation of water at the cathode leads to flooding and concomitant mass transport losses in the PEMFC due to the reduced diffusion rate of O2 reaching the cathode. 

Feind (F2), 1960 Experimental studies of film flow (water, aqueous glycol solutions) with countercurrent air flow in vertical tubes (2.0-5.0 cm. diameter). Data on mean film thicknesses, local heat transfer coefficients, pressure drop, wave heights, onset of flooding, gas/film interactions. 

The principal types of open channels are natural streams or rivers artificial canals and sewers, tunnels, or pipelines not completely filled. Artificial canals may be built to convey water for purposes of water power development, irrigation or city water supply, drainage or flood control, and numerous others. While there are examples of open channels carrying liquids other than water, there exist few experimental data for such, and the numerical coefficients given here apply only to water at natural temperatures. 

A reservoir initially is filled with water (for the simplicity of illustration, no oil is assumed in the reservoir). The CEC is 1.1 meq/L PV. The initial water is 1 mM NaNOs and 0.2 mM KNO3. The reservoir is flooded with 0.6 mM CaCb water. The exchange coefficient Kk.nb is 5. Estimate the concentration histories of these ions at the production well. 

---