Corresponding Author: Vipul Namdev 12
Email address: Vipulnamdev1995@gmail.com
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International Journal of Research in Engineering and Innovation Vol-1, Issue-1 (2016), 12-19
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International Journal of Research in Engineering and Innovation (IJREI)
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Analysis of Vortex Formation around a Circular Cylinder at low
Reynolds Number
Vipul Namdev, Prashant Kumar, Ashish Tyagi, Kartik Kumar
Graduate Student, Department of Mechanical Engineering, Meerut Institute of Technology, Meerut, India
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Keywords
Reynolds Number,
Lift coefficient
Drag coefficient
Circular Cylinder
Angle of attack
Abstract
Vortex shedding is one of the most interesting phenomenon in turbulent flow. This
phenomenon was first studied by Strouhal. In this paper, the analysis of vortex shedding
around a 2 dimensional circular cylinder with Reynolds No of 200, 500, and 1000 with
different angle of attack 0
0
, 5
0
, and 10
0
has been studied. In this simulation an implicit
pressure-based finite volume method and second order implicit scheme is used. Flow has
been studied with the help of Navier-Stokes and continuity equations. The pressure, drag
coefficients and vortex shedding for different Reynolds numbers and different angle of
attack were computed and compared with other numerical result that show good
agreement. © 2016 ijrei.com. All rights reserved
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1. Introduction
The effect of the flow over a rotating cylinder at high
rotational rates. 12 rotational rates from 0 to 8 are examined
at 3 Reynolds number, Re = 5 ×10
5
,10
6
and 5 ×10
6
. This
study shows that the lift and drag force varies slightly in the
Reynolds number range (less than 10%). Lift increases
linearly with spin ratio (a) and the drag force increases up
to a = 4, where it reaches a plateau and eventually
decreases. [1].
Investigate high Reynolds number flow (1×10
6
, 2 ×10
6
,
3.6 ×10
6
) around a smooth circular cylinder by using 2D
URANS equation with a standard K-epsilon turbulence
model for engineering applications in the supercritical and
upper-transition flow regimes was examined in this
research. The essential hydrodynamic quantities such as
coefficient of drag, lift and strouhal number predictions
shows acceptability of the data. The computed cd and skin
friction coefficient decrease slightly as the Reynolds
number increase [2].
The deflection is increased when we increased the
Reynolds Number with increase their angle of attack The
maximum deflection occur in Re-1000, angle of attack 15
0
i.e. 9.2597x10
-3
mm and minimum value of deflection
occurs in Re-100 with angle of attack 0
0
i.e.1.4618 x 10
-4
mm. the highest natural frequency 34.353 Hz was found in
mode 6 which is torsional mode, whereas minimum natural
frequency 0.6951 was found in mode [3].
The time-averaged lift and drag generation of two flexible
membrane wings with different skin flexibilities (flexible
nylon and flexible latex wings) are compared with those of
a rigid wing.The effect of the Reynolds number on the
gliding ratio is that at Re 1000 and at angle of attack (here
after, AOA) 15
0
, the largest gliding ratios are obtained.
Flow invariably for all Reynolds number, minimum Drag
coefficient is obtained at AOA 15
0
[4]
It was found that for all the simulations performed flow
always remained steady at Re 100 and 200 at all angle of
attack (0
0
to 15
0
). First unsteady flow was obtained at Re
500 and AOA 10
0
. But flow always remained steady at
AOA 0
0
and 5
0
for all the Reynolds numbers [5].
The mean drag coefficient is under predicted by this
method for a wide range and strouhal number is over
predicted. The length of separation bubble predicted shown