In the present study, the influence of superficial gas velocity and fluid properties on gas holdup and liquid circulation velocity in a three-phase external loop airlift column using polystyrene (0.0036 m diameter and 1025.55 kg/m density) and nylon-6 (0.0035 m diameter and 1084.24 kg/m density) particles with aqueous solutions of alcohols (isoamyl alcohol and propanol) as liquids were investig...

Effects of small perturbations from a liquid-gas coexistence equilibrium (the Maxwell states) is studied for an isothermal (or isentropic) gas-liquid phase transition in a sealed onedimensional finite length tube, by using a van per Waals model with a viscous-capillary regularization. A matched asymptotic expansion is used to derive formally a linear system satisfied by leading order perturbati...

In this paper, a model for closed loop solar system is presented and an attempt is made to generalize the model to be utilized for primary design of any solar active thermal system. This model may be used for systems in which gas or a liquid are fluids that flow. Two new parameters, namely, the system heat delivery factor and the system heat absorption factor are introduced in the model. These ...

Generally, unit operation processes that are used in environmental engineering are in‐ volved in interfacial reaction where mass transfer is an extremely essential component for system optimization. The purposes of this chapter were intended to provide the informa‐ tion of both theoretical model development and engineering practice for mass transfer of important processes in environmental engin...

In this contribution a micro liquid dosing system is presented, which allows bi-directional manipulation of fluids (i.e. pushing out and pulling in of liquids) by the electrochemical generation and removal of gas bubbles. Bi-directionality is obtained by reversal of the actuation current thereby causing the earlier produced gasses to react back to water. This reduction of gas volume actively pu...

Natural gas usually contains significant amounts of acid gases when it is extracted from underground reservoirs. Therefore, it must be treated by appropriate processes to remove these acidic components. In this study, the simultaneous absorption of carbon dioxide and hydrogen sulfide from natural gas into diethanol amine solution was simulated using CFD. Absorption process was performed in a we...

in this study, gas evolution in a vertical electrochemical cell is investigated numerically with a modified two-fluid model. the mathematical model involves solution of separate transport equation for the gas and liquid phases with an allowance to inter-phase transfer of mass and momentum. the governing equations are discreted via the finite volume technique and then are solved by the simple al...