Vapor–liquid phase separation in micro-/ministructured devices

Gas/vapor–liquid phase separation can generally be achieved through mechanisms such as gravity, centrifugal forces, impingement and surface tension forces. In this study several micro-/ministructured devices for the separation of gas/vapor and liquid phases are investigated numerically and experimentally. By means of CFD the two-phase flow in the devices can be visualized and studied. The devices are compared with respect to pressure drop and separation efficiency. The enhancement of the specific exchange area and reduction of the characteristic length increase the phase separation. Although the rates of heat and mass transfer and therefore the efficiency of phase separation are proportional to the pressure gradient, devices achieving nearly 100% separation efficiency at moderate pressure drops can be developed by combining multiple separation mechanisms in microstructured devices.

► A numerical/experimental study of vapor/liquid separation in microscale was accomplished.
► Phase separation is a function of the inner wall area of separators working with centrifugal forces.
► Phase separation is influenced by the orientation of devices working with gravity and surface tension.
► The most efficient way for separation is using gravity force with supporting surface tension.
► Separation efficiencies of nearly 100% can be reached.