Laminar / Transitional Loop

The Laminar/Turbulent transition loop is a gravity-driven flow facility composed of an upstream reservoir, a settling chamber, an acrylic test section, a diffuser and a downstream tank. The channel is made of transparent acrylic and has an aspect ratio of 12.5 (height of 16mm and width of 200mm). The upstream reservoir is placed 2.6 m above the test section centerline. The settling chamber is approximately 2 m long and has a nozzle with a contraction ratio of 48 to reduce turbulence and non-uniformity in the test section. The flow that passes through the acrylic test section will enter a diffuser and a small settling chamber; then, it is poured into a downstream tank. The total volume of the flow loop is 720 Liters, and the fluid can be recirculated to the upstream tank using a progressive cavity pump.

The maximum Reynolds number achieved in this flow loop is 11000. This closed-loop flow facility can be used to study the transitional flow of various fluids, for instance, non-Newtonian polymer solutions. Moreover, the acrylic test section provides perfect visual access to perform optical measurements in both spanwise and wall-normal directions.