0
Fundamental Issues and Canonical Flows

Influence of Rounded Corners on Flow Interference Due to Square Cylinders Using Immersed Boundary Method

[+] Author and Article Information
M. B. Shyam Kumar

S. Vengadesan1

Fluid Mechanics Laboratory, Department of Applied Mechanics,  Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, Indiavengades@iitm.ac.in

1

Corresponding author.

J. Fluids Eng 134(9), 091203 (Aug 22, 2012) (23 pages) doi:10.1115/1.4007015 History: Received November 23, 2011; Revised June 19, 2012; Published August 22, 2012; Online August 22, 2012

The influence of rounded corners on the aerodynamic forces and flow interference has been studied in detail for a uniform flow past two side-by-side arranged square cylinders. The Reynolds number (Re) based on the cylinder diameter (D) and free stream velocity (U∞ ) is 100. Numerical simulations are carried out for seven different transverse gap ratios (T/D), each with a minimum and maximum corner radius. An inbuilt finite difference code with staggered arrangement of flow variables is used to discretize the governing equations. The concept of immersed boundary method (IBM) is employed to simulate flow around rounded corners using the regular Cartesian grids. The computational code was validated for flow past an isolated circular cylinder, square cylinder, and two equal sized circular cylinders and the results were found to be in very good agreement with available literatures. In the present study, results in terms of the mean and rms values of lift and drag coefficients, Strouhal number, phase diagrams, and contours of streamlines and vorticity are presented. As the corner radius is increased, a reduction in the drag force is observed. There exists a significant effect of gap ratio and corner radius on the phase angle of lift and drag coefficients. Three different flow patterns, namely the single bluff body flow, biased gapside flow, and two independent bluff body flows, were observed from this study.

Copyright © 2012 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Representation of a circular cylinder in immersed boundary method

Grahic Jump Location
Figure 2

Computational domain with boundary conditions for flow past two equal sized square cylinders with rounded corners arranged side-by-side at Re=100

Grahic Jump Location
Figure 8

(a), (b) Instantaneous spanwise vorticity for flow past an isolated circular and square cylinder at Re=150, respectively

Grahic Jump Location
Figure 7

(a), (b) Mean streamlines for flow past an isolated circular and square cylinder at Re=150, respectively

Grahic Jump Location
Figure 6

(a), (b) Time history of the drag signals for flow past an isolated circular and square cylinder at Re=150, respectively

Grahic Jump Location
Figure 3

(a) A grid of size 352 × 41 × 365 generated for a gap ratio of T/D = 1.120, and (b), (c) zoomed view of the grid near the two square cylinders for R=D/8 and R=D/4, respectively

Grahic Jump Location
Figure 27

Instantaneous spanwise vorticity for flow past two square cylinders with corner radius of R=D/4 for different gap ratios at Re=100

Grahic Jump Location
Figure 26

Instantaneous spanwise vorticity for flow past two square cylinders with corner radius of R=D/8 for different gap ratios at Re=100

Grahic Jump Location
Figure 25

Instantaneous spanwise vorticity for flow past two square cylinders with sharp corners for different gap ratios at Re=100

Grahic Jump Location
Figure 24

Instantaneous streamlines for flow past two square cylinders with corner radius of R=D/4 for different gap ratios at Re=100

Grahic Jump Location
Figure 16

Comparison of bulk parameters for flow past two square cylinders with corner radius of R=D/4 and arranged side-by-side at Re=100 for seven different T/D ratios

Grahic Jump Location
Figure 15

Comparison of bulk parameters for flow past two square cylinders with corner radius of R=D/8 and arranged side-by-side at Re=100 for seven different T/D ratios

Grahic Jump Location
Figure 14

Comparison of bulk parameters for flow past two square cylinders with sharp corners and arranged side-by-side at Re=100 for seven different T/D ratios

Grahic Jump Location
Figure 13

Mean pressure distribution over the computational domain for flow past an isolated square cylinder with corner radius of R=D/4 at Re=150

Grahic Jump Location
Figure 12

Mean spanwise vorticity for flow past an isolated square cylinder with corner radius of R=D/4 at Re=150

Grahic Jump Location
Figure 11

Instantaneous spanwise vorticity for flow past an isolated square cylinder with different corner radii at Re=150

Grahic Jump Location
Figure 10

(a) Time history of the lift signals for flow past an isolated square cylinder with different corner radii at Re=150, (b) time history of the drag signals for flow past an isolated square cylinder with different corner radii at Re=150 and (c) mean streamlines for flow past an isolated square cylinder with different corner radii at Re=150

Grahic Jump Location
Figure 9

(a), (b) Time averaged surface pressure coefficient over an isolated circular and square cylinder at Re=150, respectively

Grahic Jump Location
Figure 5

(a), (b) Time history of the lift signals for flow past an isolated circular and square cylinder at Re=150, respectively

Grahic Jump Location
Figure 4

Comparison of bulk parameters at Re=150 for flow past an isolated circular and square cylinder with sharp corners

Grahic Jump Location
Figure 23

Instantaneous streamlines for flow past two square cylinders with corner radius of R=D/8 for different gap ratios at Re=100

Grahic Jump Location
Figure 22

Instantaneous streamlines for flow past two square cylinders with sharp corners for different gap ratios at Re=100

Grahic Jump Location
Figure 21

Fast Fourier transforms of the lift signals for flow past two square cylinders with corner radius of R=D/8 for different gap ratios at Re=100

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In