On the Derivation of a Stokes–Brinkman Problem from Stokes Equations Around a Random Array of Moving Spheres

Motivated by applications in solids formation and handling processes we numerically investigate the force and torque required for maintaining a fixed contact between two equally sized solid spheres immersed in fluid flow. The direct numerical procedure applied is based on solving the Navier–Stokes equations by means of the lattice-Boltzmann method, with no-slip conditions at the surfaces of the moving spheres. It is validated by means of the analytical results due to Nir & Acrivos (1973) for sphere doublets in creeping flow. Subsequently, doublets are released in turbulent flows. In these cases, the contact force and torque strongly fluctuate, with peak levels much higher than would follow from simple dimensional analysis. The force fluctuation levels have been quantified by a linear relation in the ratio of sphere radius over Kolmogorov length scale.

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Remarks on the asymptotic behaviour of solutions to the compressible Navier–Stokes equations in the half-line

Proceedings of the Royal Society of Edinburgh Section A Mathematics ◽

10.1017/s030821050200032x ◽

2002 ◽

Vol 132 (03) ◽

pp. 627

Keyword(s):

Asymptotic Behaviour ◽

Stokes Equations ◽

Half Line ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Asymptotic Behaviour Of Solutions

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DISLOCATION RELAXATION IN A RANDOM ARRAY OF SOLUTES

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1981547 ◽

1981 ◽

Vol 42 (C5) ◽

pp. C5-319-C5-324 ◽

Cited By ~ 1

Author(s):

I. G. Ritchie ◽

A. Atrens ◽

C. B. So ◽

K. W. Sprungmann

Keyword(s):

Random Array

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Effects of stator splitter blades on aerodynamic performance of a single-stage transonic axial compressor

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES ◽

10.15282/jmes.14.4.2020.05.0579 ◽

2020 ◽

Vol 14 (4) ◽

pp. 7369-7378

Author(s):

Ky-Quang Pham ◽

Xuan-Truong Le ◽

Cong-Truong Dinh

Keyword(s):

Stokes Equations ◽

Three Dimensional ◽

Axial Compressor ◽

Aerodynamic Performance ◽

Numerical Results ◽

Single Stage ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Operating Stability ◽

Length Coverage

Splitter blades located between stator blades in a single-stage axial compressor were proposed and investigated in this work to find their effects on aerodynamic performance and operating stability. Aerodynamic performance of the compressor was evaluated using three-dimensional Reynolds-averaged Navier-Stokes equations using the k-e turbulence model with a scalable wall function. The numerical results for the typical performance parameters without stator splitter blades were validated in comparison with experimental data. The numerical results of a parametric study using four geometric parameters (chord length, coverage angle, height and position) of the stator splitter blades showed that the operational stability of the single-stage axial compressor enhances remarkably using the stator splitter blades. The splitters were effective in suppressing flow separation in the stator domain of the compressor at near-stall condition which affects considerably the aerodynamic performance of the compressor.

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