Streaming flow induced by two oscillating circular cylinders

KSME Journal ◽  
1995 ◽  
Vol 9 (4) ◽  
pp. 506-514
Author(s):  
Yong Kweon Suh
Keyword(s):  
Circular Cylinders ◽  
Oscillating Circular Cylinders ◽  
Streaming Flow

Mechanisms of Enhanced Heat Transfer for Oscillating Circular Cylinders

Volume 1 ◽  
2004 ◽  
Author(s):  
Tait Pottebaum ◽  
Mory Gharib
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Enhancement ◽  
Vortex Formation ◽  
Cross Flow ◽  
Circular Cylinders ◽  
Transfer Enhancement ◽  
Heated Cylinder ◽  
Wide Range ◽  
Temperature And Velocity Fields ◽  
Oscillating Circular Cylinders

Experiments were conducted to determine the relationship between wake structure and heat transfer for an oscillating circular cylinder in cross-flow. An internally heated cylinder was suspended in a water tunnel and oscillated transverse to the freestream. The cylinder’s heat transfer coefficient was measured over a wide range of oscillation amplitudes and frequencies. By comparing these results to the known wake mode regions in the amplitude-frequency plane, relationships between wake mode and heat transfer were identified. Representative cases were investigated further by using digital particle image thermometry/velocimetry (DPIT/V) to simultaneously measure the temperature and velocity fields in the near-wake. This revealed more detail about the mechanisms of heat transfer enhancement. The dynamics of the vortex formation process, including the trajectories of the vortices during roll-up, are the primary cause of the heat transfer enhancement.

Streaming flow induced by an oscillating cascade of circular cylinders

1993 ◽  
Vol 252 ◽  
pp. 147-171 ◽  
Author(s):  
B. Yan ◽  
D. B. Ingham ◽  
B. R. Morton
Keyword(s):  
Numerical Solutions ◽  
Stokes Equations ◽  
Circular Cylinders ◽  
Navier Stokes ◽  
Grid System ◽  
Leading Order ◽  
Rectangular Grid ◽  
Navier Stokes Equations ◽  
Steady Streaming ◽  
Streaming Flow

The fluid flow induced by a cascade of circular cylinders which oscillates harmonically in an unbounded, incompressible, viscous fluid which is otherwise at rest is investigated both numerically and experimentally. Attention in this paper is mainly concentrated on the induced steady streaming flow which occurs when the ratio of the amplitude of the oscillation of the cascade to the size of the cylinder, ε, is very small. The leading-order flow is then governed by the steady Navier-Stokes equations. In order to solve these equations numerically we first generate numerically a grid system using the boundary element method and then use a finite-difference scheme on the newly generated rectangular grid system. Numerical results show that for small values of the streaming Reynolds number Rs there are four recirculating flows of equal strength around each circular cylinder of the cascade. At large values of Rs symmetry breaks down and numerical solutions are found for asymmetrical flows. Numerically, a critical value of Rs, Rso say, is identified such that the flow is symmetrical when Rs < Rso and asymmetrical when Rs > Rso and these results are in reasonable agreement with experimental results, which are also presented in this paper.

Viscous Forces Acting on Irregularly Oscillating Circular Cylinders and Flat Plates

1988 ◽  
Vol 110 (2) ◽  
pp. 140-147 ◽  
Author(s):  
Y. Ikeda ◽  
K. Osa ◽  
N. Tanaka
Keyword(s):  
Added Mass ◽  
Hydrodynamic Forces ◽  
Circular Cylinders ◽  
Flat Plates ◽  
Steady State Condition ◽  
Viscous Forces ◽  
Sinusoidal Motion ◽  
History Effect ◽  
Oscillating Circular Cylinders ◽  
Or History

In the present paper hydrodynamic forces acting on oscillating circular cylinders as well as flat plates perpendicular to the motion in regular and irregular modes due to vortex shedding are experimentally investigated in order to clarify the memory effect or history effect on the hydrodynamic forces. The experimental results for sinusoidal motion show that the drag and added mass coefficients in steady-state condition are significantly different from those of the first swing from the start because of the existence of old vortices generated in the previous cycles around the cylinder. It is found from the experiments in irregular modes that the drag and added mass coefficients significantly vary every swing. It is confirmed that these coefficients during a swing depend on the relative amplitude or the Keulegan-Carpenter number of the previous swings as well as that of the swing under consideration.

Numerical Investigation of Flow and Heat Transfer around Two Semi-Circular Cylinders with a Splitter Plate

2011 ◽  
Vol 42 (7) ◽  
pp. 595-612
Author(s):  
Masome Heidary ◽  
Mousa Farhadi ◽  
Kurosh Sedighi ◽  
Mostafa Nourollahi
Keyword(s):  
Heat Transfer ◽  
Numerical Investigation ◽  
Splitter Plate ◽  
Circular Cylinders ◽  
Flow And Heat Transfer
Sign in / Sign up

Export Citation Format

Share Document