Hydrothermal Behavior of Fluid Flow and Heat Transfer through a Curved Square Duct with Curvature Effects

08/25/2020
by   Selim Hussen, et al.
0

Due to ample applications from medical services to industrial activities, the study of flow and heat transfer through a curved duct has attracted considerable attention to the researchers. In this paper, a comprehensive numerical study is presented for the fully developed two-dimensional flow of viscous incompressible fluid through a curved square duct for various curvatures. The spectral method is used as a basic tool to solve the system of nonlinear partial differential equations. Numerical calculations are carried out over a wide range of the Dean number, 0<D_n≤ 5000, for curvature ratio δ =0.001, 0.1, and 0.5. A temperature difference is applied across the horizontal walls for the Grashof number Gr = 1000, where the bottom wall is heated while cooling from the ceiling, the outer and inner walls being thermally insulated. First, the bifurcation structure of steady solutions is investigated. As a result, two branches of steady solutions consisting of two- to eight-vortex solutions are obtained for δ =0.001 and 0.1 while three branches for δ =0.5. Then we performed time evolution calculation to investigate unsteady flow characteristics, and it is found that the unsteady flow undergoes through various flow instabilities, if D_n is increased. Flow transitions are well determined by obtaining phase space of the time evolution results. Typical contours of streamlines and isotherms are obtained at several values of D_n and it is found that the unsteady flow consists of two-to-eight-vortex solutions. The present study demonstrates the role of secondary vortices on convective heat transfer and it is found that convective heat transfer is significantly enhanced by the secondary flow and as the number of secondary vortices increases, that occurs for the chaotic solution, heat transfer is boosted substantially.

READ FULL TEXT

page 7

page 10

page 13

research
03/30/2023

Comprehensive study of forced convection over a heated elliptical cylinder with varying angle of incidences to uniform free stream

In this paper we carry out a numerical investigation of forced convectio...
research
04/25/2023

Genetically-inspired convective heat transfer enhancement in a turbulent boundary layer

The convective heat transfer in a turbulent boundary layer (TBL) on a fl...
research
02/02/2023

Impact of a Cold Control Plate on Fluid Flow and Heat Transfer across an Isothermally Heated Rotary Oscillating Circular Cylinder

The main objective of this paper is to study the effect of a cold, verti...
research
11/05/2020

Mathematical modelling of an unstable bent flow using the selective frequency damping method

The selective frequency damping method was applied to a bent flow. The m...
research
07/09/2023

Effects on two semi-circular wall heaters in a rectangular enclosure containing trapezoidal heated obstacle in presence of MHD

A computational study has been done to illustrate the effects on two sem...

Please sign up or login with your details

Forgot password? Click here to reset