Effect of Thermal Buoyancy on Vortex-Shedding and Aerodynamic Characteristics for Fluid Flow Past an Inclined Square Cylinder

2D simulation is carried out to determine exactly the effect of blockage ratio on the flow and mixed convection heat transfer characteristics of Newtonian fluid across a square cylinder confined in horizontal channel, the numerical study is investigated in the range of these conditions:Re= 10 to 30,Ri= 0 to 1 and blockage ratioβ= 1/10 to 1/2. The flow structure and temperature field are visualized in terms of streamlines and isotherm contours. The total drag coefficient and average Nusselt number are also reported to show the combined effects of thermal buoyancy, Reynolds number and blockage ratio on the hydrodynamic flow forces and heat transfer rate. The obtained results showed that the effect of thermal buoyancy on fluid flow and heat transfer becomes more pronounced by decreasing the blockage ratio.

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Power law fluid flow past a square cylinder: momentum and heat transfer characteristics

Chemical Engineering Science ◽

10.1016/j.ces.2003.09.010 ◽

2003 ◽

Vol 58 (23-24) ◽

pp. 5315-5329 ◽

Cited By ~ 55

Author(s):

B. Paliwal ◽

Atul Sharma ◽

R.P. Chhabra ◽

V. Eswaran

Keyword(s):

Heat Transfer ◽

Fluid Flow ◽

Power Law ◽

Square Cylinder ◽

Heat Transfer Characteristics ◽

Power Law Fluid ◽

Transfer Characteristics ◽

Flow Past ◽

Momentum And Heat Transfer

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Visualization of flow past square cylinders with corner modification

Journal of Mechanical and Energy Engineering ◽

10.30464/jmee.2020.4.3.285 ◽

2020 ◽

Vol 4 (3) ◽

pp. 285-294

Author(s):

Ch. Krishnappa Vikram ◽

H. V. Ravindra ◽

Y. T. Krishnegowda

Keyword(s):

Aluminum Powder ◽

Experimental Work ◽

Vortex Shedding ◽

Test Section ◽

Square Cylinder ◽

Square Cylinders ◽

Flow Past ◽

Spacing Ratio ◽

Vortex Shedding Frequency ◽

Shedding Frequency

This article presents the results for flow past a square cylinder and two square cylinders of the same and different sizes with corner modifications by varying the spacing ratio. Here, experimental work is conducted in a recirculatory channel filled with water. A set of aluminum discs made to rotate to create the flow in the test section. The motor is used to vary the speed of the water. Fine aluminum powder is used as a tracer medium. It is observed that vortex shedding frequency decreases by placing the second cylinder in the downstream of the first cylinder. For similar size cylinders, the width of the eddy in the middle of the cylinders increases with an increase in spacing ratio. With the increase of spacing ratio to 6, the flow past each cylinder behaves like a single square cylinder. If the upstream square cylinder size is smaller than the downstream square cylinder, the eddy size is reduced in between the cylinder compared to the downstream of the second cylinder. If the upstream square cylinder size is bigger than the downstream square cylinder, the eddy size is larger in between the cylinder compared to the downstream of the second cylinder.

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Effect of rounded corners on two degree of freedom naturally oscillating square cylinder

International Journal of Numerical Methods for Heat &amp Fluid Flow ◽

10.1108/hff-06-2016-0248 ◽

2017 ◽

Vol 27 (10) ◽

pp. 2355-2374 ◽

Cited By ~ 4

Author(s):

Sajjad Miran ◽

Chang Hyun Sohn

Keyword(s):

Vortex Shedding ◽

Frequency Ratio ◽

Degrees Of Freedom ◽

Aerodynamic Characteristics ◽

Two Dimensions ◽

Cylinder Wake ◽

Square Cylinder ◽

Content Type ◽

Oscillating Square Cylinder ◽

Drag And Lift

Purpose The paper aims to study the influence of rounded corners on the flow-induced oscillation of a square cylinder that is free to oscillate in two degrees of freedom. Design/methodology/approach The finite volume code in conjunction with the moving mesh scheme was implemented via a user-defined function to carry out the computations in two dimensions. The Reynolds number (Re) chosen for the present study is fixed at 100, and the frequency ratio, Fr = fs/fn (where fs is the vortex shedding frequency and fn is the natural frequency of cylinder) is used as a varying parameter. The computational model was validated for flow past a stationary cylinder with R/D = 0 and 0.5, and the results showed good agreement with the literature. Findings The aerodynamic characteristics, amplitude response, trajectories of cylinder motion and vortex shedding modes are obtained by conducting a series of simulations under different frequency ratios of the cylinder. It was found that the minimum transverse amplitude, drag force and lift force obtained for a naturally oscillating square cylinder are quite different when compared with a stationary and forced oscillating cylinder, where the maximum drag and lift forces were observed for a square cylinder and a minimum around R/D = 0.2 was observed. Originality/value The present work identified the significant effect of the varying frequency ratio and R/D on the VIV modes of the cylinder. It was observed that the cylinder wake exhibits the (2S) vortex shedding mode for R/D = 0 to 0.2 at all Fr, whereas the C (2S) mode appeared for R/D > 0.2 at Fr = 1.1.

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