Interfacial Instabilities in Rotating Hele-Shaw Cell: A Review

We have reported the interfacial instabilities or viscous fingering instabilities in rotating radial Hele-Shaw cell (HSC). The cell is rotated with constant or time-dependent angular velocity about an axis perpendicular to the plane of the flow. Inside the cell, a low viscous fluid displaces a high viscous fluid. Due to this unstable displacement inside the cell fingers like pattern appears at the fluid–fluid interface. It is called viscous fingering (VF). Interfacial instabilities are usually undesirable in engineering applications (dendritic growth decreases the life of rechargeable lithium batteries, VF decreases sweep area due to this reason efficiency of enhanced oil recovery decreases) but it is also beneficial for some practical applications (improving the CO2 mixing in saline aquifers for carbon sequestration, enhancing the mixing efficiency in microfluidics devices). Therefore active control (suppress or promote) of the interfacial instabilities is an important aspect. Many researchers have been done work on active control of interfacial instabilities in radial rotating HSC. A few of them we have taken in this paper. Researchers have been found fluid–fluid interfaces destabilized in radial rotation HSC mainly by centrifugal forces (density differences) and viscosity contrast. The interfacial instability in the radial rotating Hele-Shaw cell depends on rotational velocity (Ὼ), gap between plates (b), wettability of cell, viscosity, density and surface tension. We have reported many research works related to active control of interfacial instability by the above parameters in radial rotating radial HSC.