Unsteady Features of Laminar Viscous Incompressible Flow and Temperature Dissemination through a Rotating Bent Rectangular Channel: The Case of Negative Rotation

Abstract

The current study investigates the effects of rotation on fluid flow and heat transfer through a curved channel of rectangular cross-section with bottom wall heated and cooling from the top. A wide range of the Taylor number with constant curvature = 0.2, aspect ratio 2 and the Prandtl number Pr = 7.0 (water) have been considered for the study. After a broad investigation to explore transient flow behavior, time-history analysis is performed using phase trajectory of the transient solutions at fully developed stage. As a result, the stages of transient flow endure in the consequence “chaotic → periodic → multi-periodic → chaotic” for the rotating system in the negative direction comprising with 2- to 8- vortex solutions. It is further illustrated from stream function and energy distribution that the heat transfer is ominously enhanced at high rotation and the chaotic flow enhances heat transfer more significantly than the steady-state, periodic or other physically realizable solutions. Finally, the current numerical results are compared with laboratory-based experimental results and a good agreement is observed.

Compressibility Effects on Turbulent Heat Transfer of Natural Convection in a Square Cavity

“…For example, it applies to heat exchangers [1][2][3][4][5] used by fossils, chemical power plants, and nuclear reactors [6] . In laminar flows, many studies [7][8][9][10][11][12][13][14][15] consider fluids undergoing heat transfer as incompressible, i.e., their density is constant regardless of their change in temperature and pressure. This assumption only applies if the temperature difference is below 2℃ for water and 15℃ for air [16] .…”