Fluid Flow Structures in Staggered Banks of Cylinders Located in a Channel

1995 ◽  
Vol 117 (1) ◽  
pp. 36-44 ◽  
Author(s):  
M. J. Braun ◽  
V. V. Kudriavtsev
Keyword(s):  
Fluid Flow ◽  
Numerical Experiments ◽  
Reynolds Numbers ◽  
Flow Structures ◽  
Wall Jet ◽  
Square Channel ◽  
Pressure Distributions ◽  
Geometric Configurations ◽  
Model Fluid ◽  
Flow Through

This paper contains numerical experiments that model fluid flow through a staggered array of cylinders and represents a continuation of work previously performed by the authors (Braun et al., 1993; Kudriavstsev et al., 1993). The results shown here concentrate on the analysis of the physics of flow and pressure distribution in (i) one row of cylinders, and (ii) seven rows of cylinders. The test section is the same square channel described by Braun et al. (1993). The numerical experiments were run in transient mode at Reynolds numbers (Re = umaxd/v) ranging from 86 to 869. The primary purpose of this paper is to report qualitative results regarding the attached near-wall jet phenomenon and to discuss its flow mechanics. The authors compare various stages of the transient evolution of the flow structures for geometric configurations that contain one, and seven rows of pins respectively. The associated pressure distributions in the arrays of pins are also discussed.

An Experimental Study of Fluid Flow in Disk Cavities

1992 ◽  
Vol 114 (2) ◽  
pp. 454-461 ◽  
Author(s):  
S. H. Bhavnani ◽  
J. M. Khodadadi ◽  
J. S. Goodling ◽  
J. Waggott
Keyword(s):  
Experimental Study ◽  
Fluid Flow ◽  
Gas Turbine ◽  
Experimental Studies ◽  
Reynolds Numbers ◽  
Turbine Disk ◽  
Published Data ◽  
Disk System ◽  
Flow Rates ◽  
Pressure Distributions

Results are presented for an experimental study of fluid flow in models of gas turbine disk cavities. Experiments were performed on 70-cm-dia disks for rotational Reynolds numbers up to 2.29 × 106. Velocity and pressure distributions are presented and compared to previous theoretical and experimental studies for a free disk, and an unshrouded plane Rotor–Stator disk system. Minimum coolant flow rates for the prevention of ingress, determined for the case of a simple axial rim seal, compare well with previously published data.

Eyring-Powell fluid flow through a wall jet in the presence of viscous dissipation

2018 ◽  
Vol 133 (8) ◽  
Author(s):  
Syed Zulfiqar Ali Zaidi ◽  
Syed Tauseef Mohyud-Din ◽  
Umar Khan ◽  
Naveed Ahmad
Keyword(s):  
Fluid Flow ◽  
Viscous Dissipation ◽  
Wall Jet ◽  
Flow Through

scholarly journals Analysis of vortices in viscoelastic fluid flow through confined geometries at low Reynolds numbers

AIP Advances ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 085213
Author(s):  
Ali Zargartalebi ◽  
Mohammad Zargartalebi ◽  
Anne M. Benneker
Keyword(s):  
Fluid Flow ◽  
Viscoelastic Fluid ◽  
Reynolds Numbers ◽  
Confined Geometries ◽  
Low Reynolds Numbers ◽  
Flow Through ◽  
Low Reynolds

Measurements of Turbulent Transport in a Square Channel with One Ribbed Wall

2022 ◽  
Author(s):  
Sebastian Ruck ◽  
Frederik Arbeiter
Keyword(s):  
Reynolds Number ◽  
Shear Stress ◽  
Shear Layer ◽  
Reynolds Shear Stress ◽  
Turbulent Transport ◽  
Reynolds Numbers ◽  
Flow Structures ◽  
Channel Height ◽  
Height Ratio ◽  
Square Channel

Abstract The velocity field of the fully developed turbulent flow in a one-sided ribbed square channel (rib-height-to-channel-height ratio of k/h = 0.0667, rib-pitch-to-rib-height ratio of p/k = 9) were measured at Reynolds numbers (based on the channel height h and the mean bulk velocity uB) of Reh = 50 000 and 100 000 by means of Laser-Doppler-Anemometry (LDA). Triple velocity correlations differed slightly between both Reynolds numbers when normalized by the bulk velocity and the channel height, similarly to the first- and second-order statistical moments of the velocity. Their near-wall behavior reflected the crucial role of turbulent transport near the rib crest and within the separated shear layer. Sweep events occurred with the elongated flow structures of the flapping shear layer and gained in importance towards the channel bottom wall, while strong ejection events near the rib leading and trailing edges coincided with flow structures bursting away from the wall. Despite the predominant occurrence of sweep events close to the ribbed wall within the inter-rib spacing, ejection events contributed with higher intensity to the Reynolds shear stress. Ejection and sweep events and their underlying transport phenomena contributing to the Reynolds shear stress were almost Reynolds number-insensitive in the resolved flow range. The invariance to the Reynolds number can be of benefit for the use of scale-resolving simulation methods in the design process of rib structures for heat exchange applications.

Experiments on the Resistance Law for Non-Darcy Compressible Gas Flows in Porous Media

1974 ◽  
Vol 96 (4) ◽  
pp. 353-357 ◽  
Author(s):  
B. A. Masha ◽  
G. S. Beavers ◽  
E. M. Sparrow
Keyword(s):  
Reynolds Number ◽  
Porous Material ◽  
Incompressible Flow ◽  
Gas Flow ◽  
Strong Support ◽  
Reynolds Numbers ◽  
Gas Flows ◽  
Pressure Distributions ◽  
Flow Through ◽  
Compressible Gas

Experiments were performed to examine the resistance law for non-Darcy compressible gas flow through a porous material. A particular objective of the investigation was to determine whether a resistance law deduced from incompressible flow experiments could be applied to flows with significant density changes. To this end, the coefficients appearing in the Forchheimer resistance law were first determined from experiments in the incompressible flow regime. These values were then used in an analytical model employing the Forchheimer resistance law to predict streamwise pressure distributions for subsonic compressible flow through the porous material. Corresponding experimental pressure distributions were measured for flow Reynolds numbers up to 81.6. At the highest Reynolds number of the tests the density changed by about a factor of two along the length of the porous medium. The greatest discrepancy between experimental and predicted pressures at any Reynolds number was 2 percent. This agreement lends strong support to the validity of using the incompressible Forchheimer resistance law for subsonic flows in which density changes are significant.

scholarly journals A pore scale study on fluid flow through two dimensional dual scale porous media with small number of intraparticle pores

2016 ◽  
Vol 18 (1) ◽  
pp. 80-92 ◽  
Author(s):  
Safa Sabet ◽  
Moghtada Mobedi ◽  
Turkuler Ozgumus
Keyword(s):  
Porous Media ◽  
Fluid Flow ◽  
Stokes Equations ◽  
Permeability Tensor ◽  
Navier Stokes ◽  
Pore Scale ◽  
Navier Stokes Equations ◽  
Pressure Distributions ◽  
Flow Through ◽  
Dual Scale

Abstract In the present study, the fluid flow in a periodic, non-isotropic dual scale porous media consisting of permeable square rods in inline arrangement is analyzed to determine permeability, numerically. The continuity and Navier-Stokes equations are solved to obtain the velocity and pressure distributions in the unit structures of the dual scale porous media for flows within Darcy region. Based on the obtained results, the intrinsic inter and intraparticle permeabilities and the bulk permeability tensor of the dual scale porous media are obtained for different values of inter and intraparticle porosities. The study is performed for interparticle porosities between 0.4 and 0.75 and for intraparticle porosities from 0.2 to 0.8. A correlation based on Kozeny-Carman relationship in terms of inter and intraparticle porosities and permeabilities is proposed to determine the bulk permeability tensor of the dual scale porous media.

Module Friction Factors and Intramodular Pressure Distributions for Periodic Fully Developed Turbulent Flow in Rectangular Interrupted-Plate Ducts

1988 ◽  
Vol 110 (2) ◽  
pp. 147-154 ◽  
Author(s):  
R. K. McBrien ◽  
B. R. Baliga
Keyword(s):  
Turbulent Flows ◽  
Static Pressure ◽  
Rectangular Cross Section ◽  
Reynolds Numbers ◽  
Plate Spacing ◽  
Pressure Distributions ◽  
Geometric Configurations ◽  
Friction Factors ◽  
Mean Pressure ◽  
Fully Developed Turbulent Flow

This paper presents detailed time-mean pressure measurements for periodic fully developed turbulent flows in straight interrupted-plate ducts of rectangular cross section. Several combinations of plate spacing and duct aspect ratio are investigated for Reynolds numbers, based on a module hydraulic diameter, in the range 5000 to 45000. The experiments undertaken in this work establish the existence of steady, time-mean, periodic fully developed flows for all flow rates and geometric configurations investigated. The results include graphical and tabular presentations of module friction factor versus Reynolds number data, and intramodular time-mean wall static pressure distributions. The physical implications of these results are also discussed.

Fluid Flow Bifurcation in Micro-Channels

2003 ◽  
Author(s):  
S. Patel ◽  
D. Drikakis
Keyword(s):  
Fluid Flow ◽  
Numerical Study ◽  
Reynolds Numbers ◽  
Flow Transition ◽  
Incompressible Fluid Flow ◽  
Low Reynolds Numbers ◽  
Multigrid Algorithm ◽  
Micro Channels ◽  
Micro Flows ◽  
Flow Through

The paper presents a numerical study of incompressible fluid flow through micro-channels. Using a high-resolution numerical method (second-order accurate) in conjunction with a non-linear multigrid algorithm and the pseudo-compressibility approach, we have investigated micro-flows through straight channels, as well as through a sudden contraction-expansion geometry. For the straight channel geometry, the computational results are in reasonable agreement with the experimental data for various low Reynolds numbers. For the contraction-expansion geometry, the results reveal the flow transition to instability. This is manifested in the form of asymmetric separation downstream of the expansion.

Sign in / Sign up

Export Citation Format

Share Document