Experimental and Numerical investigation of flow in a lid-driven cylindrical cavity

Identifier:  TDX:3850

Handle: https://hdl.handle.net/20.500.11797/TDX3850

Authors:  Selvaraj, Joshua David

Abstract:
The flow in a cylindrical cavity with a rotating lid is investigated using experimental and computational tools. The rotational speed of the lid is either kept constant with time or varied periodically with an amplitude of -20% to 20% from the mean angular velocity. The Reynolds number, defined with the radius and the maximum linear velocity of the lid is varied from 2800 to 4100. The height to radius ratio of the cylinder is H/R=2. Particle Image velocimetry (PIV) is used to measure the velocity field. The results are analysed with Computational Fluid Dynamics simulations using DNS for Re =2800. The sinusoidal or periodic rotation of the lid results in increased velocity fluctuations intensifying the flow fluctuations up to 30% compared to a constant rotational speed. The flow and mixing behaviour in the cylindrical cavity with a rotating lid having constant rotation and sinusoidal angular velocity at Reynolds number Re = 2800 is also analyzed. The cylindrical cavity is designed with two holes at the circular bottom wall, one at the centre and the other at a distance R/2 from the cavity axis. The mixing of flow injections through these holes is experimentally measured using PLIF. The flow structures obtained at several periodic rotations were measured and it has been found that the sinusoidal rotation of the lid mixes the fluids rapidly.