Experimental study on radial temperature gradient effect of a Taylor–Couette flow with axial wall slits

• Published in: Experimental thermal and fluid science Vol. 35; no. 7; pp. 1282 - 1292
• Main Authors: Liu, Dong, Kang, In-Su, Cha, Jae-Eun, Kim, Hyoung-Bum
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.10.2011; Elsevier
• Subjects: Computational fluid dynamics; Cylinders; Exact sciences and technology; Fluid dynamics; Fluid flow; Fundamental areas of phenomenology (including applications); Grashof number; Hydrodynamic stability; Instability of shear flows; Instrumentation for fluid dynamics; Physics; Slit wall; Slits; Taylor–Couette flow; Temperature gradient; Transition to turbulence; Turbulence; Turbulent flow; Turbulent flows, convection, and heat transfer; Walls; Grashof number; Taylor–Couette flow; Slit wall; Temperature gradient; Test facilities; Taylor vortex; Annular space; Temperature gradients; Transition flow; Experimental study; Turbulent laminar transition; Slot; Particle image velocimetry; Couette flow; Coaxial cylinders; Rotating cylinder; Velocity measurement; Taylor-Couette flow
• ISSN: 0894-1777; 1879-2286
• DOI: 10.1016/j.expthermflusci.2011.04.016

The flow between two concentric cylinders with the inner cylinder rotating and an imposed radial temperature gradient was studied using a digital particle image velocimetry method. The flow transition process under both a positive and negative temperature gradient with four different models of a stationary outer cylinder without and with differing numbers of slits (6, 9 and 18) was studied. The results showed that the buoyant force due to the temperature gradient clearly generated a helical flow when the rotating Reynolds number was small. For the plain and 6-slit models, the transition to a turbulent Taylor vortex flow was not affected by the temperature gradient considered in this study. In addition, the transition process of a larger number of slits (9-, 18-slit models) was accelerated due to the slit wall. As the temperature gradient became larger, the critical Reynolds number of the transition process decreased.