The Galerkin weighted residuals method is extended solve the laminar, fully developed flow and heat transfer of Al2O3-water nanofluid inside polygonal ducts with round corners for the constant heat flux and uniform wall temperature boundary conditions. Using the method, semi-analytical, closed-form solutions are obtained for the friction coefficient and the Nusselt number in terms of the radius...

Abstract We revisit the computation of bubble wall friction during a cosmological first-order phase transition, using an extended fluid Ansatz to solve linearized Boltzmann equation. A singularity is found in fluctuations background species as approaches speed sound. Using hydrodynamics, we argue that discontinuity across sound expected on general grounds, which manifests itself solution system...

In this paper, we propose a new derivation for the Green-Kubo relationship for the liquid-solid friction coefficient characterizing hydrodynamic slippage at a wall. It is based on a general Langevin approach for the fluctuating wall velocity involving a non-Markovian memory kernel with vanishing time integral. The calculation highlights some subtleties of the wall-liquid dynamics leading to sup...

The characteristics of fully-developed, laminar, pressure-driven, incompressible flow in rough circular microchannels are studied. A novel analytical model is developed that predicts the increase in pressure drop due to wall roughness in microtubes. The wall roughness is assumed to posses a Gaussian isotropic distribution. The present model is compared with experimental data, collected by other...

The iron content of the ore used is crucial for the productivity and coke consumption rate in blast furnace pig iron production. Therefore, most iron ore deposits are processed in beneficiation plants to increase the iron content and remove impurities. In several comminution stages, the particle size of the ore is reduced to ensure that the iron oxides are physically liberated from the gangue. ...

To evaluate the clinical incidence and outcomes of patients with pericarditis after thrombolytic therapy, 810 patients were prospectively studied during acute myocardial infarction (AMI). Pericarditis was defined as the presence of a pericardial friction rub during the hospital course. Only 5% of patients developed a rub during AMI, a low percent compared with that in the prethrombolytic era. A...

A near-wall subgrid-scale (SGS) model is used to perform large-eddy simulation (LES) of the developing, smooth-wall, zero-pressure-gradient flat-plate turbulent boundary layer. In this model, the stretched-vortex, SGS closure is utilized in conjunction with a tailored, near-wall model designed to incorporate anisotropic vorticity scales in the presence of the wall. Large-eddy simulations of the...

Hydrodynamic interactions in a suspension of spherical particles confined between two parallel planar walls are studied under creeping-flow conditions. The many-particle friction matrix in this system is evaluated using our novel numerical algorithm based on transformations between Cartesian and spherical representations of Stokes flow. The Cartesian representation is used to describe the inter...

The aim of this paper is to present non-similar solutions of a steady laminar compressible boundary layer flow past a long thin circular cylinder including the effects of wall enthalpy and surface mass transfer. The governing equations along with the boundary conditions are first converted into dimensionless form by a non-similar transformation, and then the resulting system of coupled non-line...

Wall-roughness induces extra drag in wall-bounded turbulent flows. Mapping any given roughness geometry to its fluid dynamic behaviour has been hampered by the lack of accurate and direct measurements skin-friction drag. Here Taylor-Couette (TC) system provides an opportunity as it is a closed allows directly reliably measure skin-friction. However, wall-curvature potentially complicates connec...