A Study on the Two-Dimensional Jet Impinging on a Circular Cylinder. 1st Report, Measurements of Flow-Field and Heat Transfer around a Circular Cylinder Mounted near Two Flat Plates.

A number of new closed-form fundamental solutions for the two-dimensional generalized unsteady Oseen and Stokes flows associated with arbitrary time-dependent translational and rotational motions have been developed. As an example of application, the hydrodynamic force acting on a circular cylinder translating in an unsteady flow field at low Reynolds numbers is calculated using the new generalized fundamental solutions.

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Fluid flow and heat transfer in wavy sinusoidal channels. 1st report Numerical analysis of two dimensional laminar flow field.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.53.722 ◽

1987 ◽

Vol 53 (487) ◽

pp. 722-730 ◽

Cited By ~ 2

Author(s):

M. Reza MOTAMED EKTESABI ◽

Mitsuo SAKO ◽

Tokuo CHIBA

Keyword(s):

Heat Transfer ◽

Fluid Flow ◽

Numerical Analysis ◽

Laminar Flow ◽

Flow Field ◽

Two Dimensional ◽

Flow And Heat Transfer

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Two-dimensional simulation of unsteady heat transfer from a circular cylinder in crossflow

Journal of Fluid Mechanics ◽

10.1017/s0022112006002941 ◽

2007 ◽

Vol 570 ◽

pp. 177-215 ◽

Cited By ~ 21

Author(s):

SALEM BOUHAIRIE ◽

VINCENT H. CHU

Keyword(s):

Heat Transfer ◽

Reynolds Number ◽

Circular Cylinder ◽

Reynolds Numbers ◽

Boundary Layer Separation ◽

Length Scale ◽

Two Dimensional ◽

Dimensional Model ◽

Transfer Rates ◽

Two Dimensional Model

The heat transfer from the surface of a circular cylinder into a crossflow has been computed using a two-dimensional model, for a range of Reynolds numbers from Re=200 to 15550. The boundary-layer separation, the local and overall heat-transfer rates, the eddy- and flare-detachment frequencies and the width of the flares were determined from the numerical simulations. In this range of Reynolds numbers, the heat-transfer process is unsteady and is characterized by a viscous length scale that is inversely proportional to the square root of the Reynolds number. To ensure uniform numerical accuracy for all Reynolds numbers, the dimensions of the computational mesh were selected in proportion to this viscous length scale. The small scales were resolved by at least three nodes within the boundary layers. The frequency of the heat flares increases, and the width of each flare decreases, with the Reynolds number, in proportion to the viscous time and length scales. Despite the presence of three-dimensional structures for the range of Reynolds numbers considered, the two-dimensional model captures the unsteady processes and produced results that were consistent with the available experimental data. It correctly simulated the overall, the front-stagnation and the back-to-total heat-transfer rates.

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Flow field and heat transfer on the base surface of a finite circular cylinder in crossflow

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2011.10.029 ◽

2012 ◽

Vol 49 ◽

pp. 79-88 ◽

Cited By ~ 16

Author(s):

Rosaria Giordano ◽

Andrea Ianiro ◽

Tommaso Astarita ◽

Giovanni Maria Carlomagno

Keyword(s):

Heat Transfer ◽

Circular Cylinder ◽

Flow Field ◽

Base Surface

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Heat Transfer Measurements Downstream of a Two-Dimensional Jet Entering a Crossflow

Journal of Turbomachinery ◽

10.1115/1.3262150 ◽

1987 ◽

Vol 109 (4) ◽

pp. 572-578 ◽

Cited By ~ 5

Author(s):

S. Wittig ◽

V. Scherer

Keyword(s):

Heat Transfer ◽

Flow Field ◽

Pressure Distribution ◽

Momentum Flux ◽

Static Pressure ◽

Flux Ratio ◽

Main Flow ◽

Two Dimensional ◽

Reattachment Point ◽

Static Pressure Distribution

Nusselt and Stanton numbers have been evaluated in and behind the recirculating zone produced by a two-dimensional jet entering a crossflow. The momentum flux ratio of the jet to the main flow was varied from 1.44–8.4 and measurements of the static pressure distribution and of the flow field by a five-hole probe were performed. A relation between the location of the reattachment point of the flow and the maximum of heat transfer was observed. Comparisons with available data are made. The experiments are intended for the verification of calculational codes.

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Large structure in the far wakes of two-dimensional bluff bodies

Journal of Fluid Mechanics ◽

10.1017/s0022112088001314 ◽

1988 ◽

Vol 190 ◽

pp. 265-298 ◽

Cited By ~ 175

Author(s):

John M. Cimbala ◽

Hassan M. Nagib ◽

Anatol Roshko

Keyword(s):

Circular Cylinder ◽

Hydrodynamic Instability ◽

Broad Band ◽

Parametric Instability ◽

Driving Mechanism ◽

Bluff Bodies ◽

Two Dimensional ◽

Large Structure ◽

Flat Plates ◽

Far Wake

Smoke-wire flow visualization and hot-wire anemometry have been used to study near and far wakes of two-dimensional bluff bodies. For the case of a circular cylinder at 70 < Re < 2000, a very rapid (exponential) decay of velocity fluctuations at the Kármán-vortex-street frequency is observed. Beyond this region of decay, larger-scale (lower wavenumber) structure can be seen. In the far wake (beyond one hundred diameters) a broad band of frequencies is selectively amplified and then damped, the centre of the band shifting to lower frequencies as downstream distance is increased.The far-wake structure does not depend directly on the scale or frequency of Kármán vortices shed from the cylinder; i.e. it does not result from amalgamation of shed vortices. The growth of this structure is due to hydrodynamic instability of the developing mean wake profile. Under certain conditions amalgamation can take place, but is purely incidental, and is not the driving mechanism responsible for the growth of larger-scale structure. Similar large structure is observed downstream of porous flat plates (Re ≈ 6000), which do not initially shed Kármán-type vortices into the wake.Measured prominent frequencies in the far cylinder wake are in good agreement with those estimated by two-dimensional locally parallel inviscid linear stability theory, when streamwise growth of wake width is taken into account. Finally, three-dimensionality in the far wake of a circular cylinder is briefly discussed and a mechanism for its development is suggested based on a secondary parametric instability of the subharmonic type.

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