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

2012 ◽  
Vol 134 (9) ◽  
Author(s):  
M. B. Shyam Kumar ◽  
S. Vengadesan
Keyword(s):  
Immersed Boundary Method ◽  
Bluff Body ◽  
Immersed Boundary ◽  
Drag Coefficients ◽  
Square Cylinders ◽  
Flow Past ◽  
Corner Radius ◽  
Boundary Method ◽  
Lift And Drag ◽  
Flow Interference

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.

MHD flow past a circular cylinder using the immersed boundary method

2010 ◽  
Vol 39 (2) ◽  
pp. 345-358 ◽  
Author(s):  
D.G.E. Grigoriadis ◽  
I.E. Sarris ◽  
S.C. Kassinos
Keyword(s):  
Circular Cylinder ◽  
Immersed Boundary Method ◽  
Mhd Flow ◽  
Immersed Boundary ◽  
Flow Past ◽  
Boundary Method

Benchmark simulations of flow past rigid bodies using an open-source, sharp interface immersed boundary method

2017 ◽  
Vol 1 (1) ◽  
pp. 1 ◽  
Author(s):  
Clarence W. Rowley ◽  
Alexander J. Smits ◽  
Nicoleta Herzog ◽  
Hrvoje Jasak ◽  
Daniel Brunner ◽  
...  
Keyword(s):  
Open Source ◽  
Immersed Boundary Method ◽  
Rigid Bodies ◽  
Sharp Interface ◽  
Immersed Boundary ◽  
Flow Past ◽  
Boundary Method

scholarly journals An Improved Direct-Forcing Immersed Boundary Method for Fluid-Structure Interaction Simulations

2013 ◽  
Author(s):  
Xing Zhang ◽  
Xiaojue Zhu ◽  
Guowei He
Keyword(s):  
Immersed Boundary Method ◽  
Fluid Structure Interaction ◽  
Three Dimensional ◽  
Immersed Boundary ◽  
Fluid Structure ◽  
Structure Interaction ◽  
Dimensional Flow ◽  
Flow Past ◽  
Boundary Method ◽  
Direct Forcing

Simulation of fluid-structure interaction (FSI) of flexible bodies are challenging due to complex geometries and freely moving boundaries. Immersed boundary method has found to be an efficient technique for dealing with FSI problems because of the use of non-body-fitted mesh and simple implementation. In the present work, we developed a FSI solver by coupling a direct forcing immersed boundary method for the fluid with a finite difference method of the structure. Several flow problems are simulated to validate our method. The testing cases include flow over a stationary cylinder and flat plate, two-dimensional flow past an inextensible flexible filament and three-dimensional flow past a flag. The results obtained agree well with those from previously published literatures.

Immersed Boundary Method for Simulation of Oscillatory Flow Past a Submerged Cylinder Near Above a Horizontal Bed

2014 ◽  
Author(s):  
Efstratios N. Fonias ◽  
Athanassios A. Dimas
Keyword(s):  
Reynolds Number ◽  
Immersed Boundary Method ◽  
Oscillatory Flow ◽  
Stokes Equations ◽  
Immersed Boundary ◽  
Critical Range ◽  
Flow Past ◽  
Boundary Method ◽  
Flow Past A Cylinder ◽  
Submerged Cylinder

In the present work, the oscillatory flow past a submerged cylinder near above a horizontal bed is simulated by a Navier-Stokes equations solver. The boundary conditions, i.e., the no-slip condition on solid boundaries are imposed with the immersed boundary method. A Cartesian grid with variable size is used for the spatial discretization, and a time-splitting scheme is used for the temporal discretization. The numerical method was validated simulating the unidirectional flow past a cylinder at Reynolds number ReD = 300. For the oscillatory flow past a cylinder of diameter D at a distance G above a horizontal bed, all variables were rendered dimensionless using the maximum velocity, Uo, and the amplitude of the orbital motion, αo, of the oscillatory flow. Several tests with differing values of αo/D and G/D were considered, for Reynolds number Reα = 5,000 and Keulegan–Carpenter numbers in the range from 6.28 to 62.8. Results show that the critical range for the suppression of vortex shedding at the lower side of the cylinder is G/αo<0.01, while the critical range for the generation of vorticity uplift from the bed boundary layer is G/αo<1.0. Also, as G/D decreases, both the amplitude of the drag force and the bias towards positive values of the lift force increase.

Numerical Investigation of Vortex Shedding Modes of Flow past Two Circular Cylinders in Side-by-Side Using Immersed Boundary Method

2013 ◽  
Vol 275-277 ◽  
pp. 482-485
Author(s):  
Li Wei Song ◽  
Song Ping Wu
Keyword(s):  
Vortex Shedding ◽  
Immersed Boundary Method ◽  
Stokes Equations ◽  
Circular Cylinders ◽  
Immersed Boundary ◽  
Step Method ◽  
Fractional Step Method ◽  
Flow Past ◽  
Boundary Method ◽  
Vortex Shedding Modes

The vortex shedding modes of flow past two circular cylinders in side-by-side arrangement are investigated numerically in this paper. The simulations are carried out using a ghost cell immersed boundary method which imposes the boundary condition through reconstruction of the local velocity field near the immersed boundary. The two-dimensional unsteady incompressible Navier-Stokes equations are solved using an implicit fractional step method based on cell-center, collocated arrangement of the primary variables. Vorticity contours of the flow around the cylinders and force time histories are presented. Anti-phase and in-phase vortex shedding modes were found to exist in the flow simulation. These results of simulations were in agreement with phenomena observed in experiment and numerical results of previous researchers.

Sign in / Sign up

Export Citation Format

Share Document