CRITICAL PARAMETERS FOR SHEAR THICKENING FLUID FLOW ACROSS A CHANNE CONFINED CIRCULAR CYLINDER

Abstract

The flow past a cylinder is an important flow type, occurs in industries like food processing, polymer etc. It plays an important role in unit operations like heat exchangers. The present study focuses on the two-dimensional Poiseuille flow of power law fluid across a circular cylinder placed between two parallel plates (Fig. I). In particular, the conditions for the formation of wake and the onset of wake instability are investigated numerically using finite volume method. The flow field equations (i.e., continuity and momentum equations) in conjunction with realistic boundary conditions have been solved using the open source computational fluid dynamics solver, OpenFOAM. i.e., Open source Field Operation and Manipulation (Version 2.3.0). The range of Reynolds number were varied from IRe45O, whereas for power law index it varied as ln1 .8. A range of blockage ratio (I . I3l 0) has been studied. It has been noticed that with decrease in blockage ratio the flow separation delays, also a delay was noticed in case of transition from steady wake to unsteady wake formation. Few global parameters like Drag coefficient and Lift coefficient were also investigated.