A high Hele-Shaw cell based on Tank-in-Tank configuration

A high vertical "Hele-Shaw" apparatus for the quasi-2D fluid experiments has been proposed to address large deformation of high channel due to static fluid pressure. The apparatus is designed with a "Tank in Tank" configuration and consists of an outer tank and an inner tank. The outer tank is cuboid-shaped and used to load fluid medium, while the inner tank consisting of two pieces of parallelly installed glass serves as the experimental channel. The pressures acting on the channel are balanced so that a high-level uniformity is maintained over the whole channel. Both heavy/light experimental objects can fall/rise freely along the channel to achieve a 2D motion style. The channel area is around 2800×1500 mm, while the gap distance of the channel can be adjusted from 0 to 120 mm. A case experiment utilizing a circular disk freely falling from rest is implemented. Four distinct falling styles have been found and visualized. The effects of the channel gap distance and disk diameter on the falling motion are discussed. As measured, a flow with Reynolds number from 400 to 63000 can be realized in this study. A theoretical model is established to characterize basic features of the apparatus. Some potential research fields and improvements of the apparatus are suggested finally.