introduction: for a velocity profile in turbulent flows, the flow conditions in the vicinity of the wall are described by logarithmic law of the wall. however, it has been extensively verified that the log-law does not apply in the outer region of the boundary layer. for example, in free surface flows, the law of the wall holds only for 20 percent of the flow depth from the wall. coles (1956) c...

In this research, the numerical method of computational fluid dynamics and dimensionless parameter of Froude number have been applied to determine the flow regime over ogee spillways.Froude number is a dimensionless dynamic parameter calculated using the square root of the ratio of inertia force and gravitational force. Considering that the study of the regimes of flow over hydraulic structures...

The aim of the present study is deriving an analytical solution to incompressible thermal flow in a micro-Couette geometry in the presence of a pressure gradient using Burnett equations with first- and second-order slip boundary conditions. The lower plate of the micro-Couette structure is stationary, whereas the upper plate moves at a constant velocity. Non-dimensional axial velocity and tempe...

This paper addresses the dam-break problem for particle suspensions, that is, the flow of a finite volume of suspension released suddenly down an inclined flume. We were concerned with concentrated suspensions made up of neutrally buoyant non-colloidal particles within a Newtonian fluid. Experiments were conducted over wide ranges of slope, concentration and mass. The major contributions of our...

A mathematical model is developed to study the MHD oscillatory blood flow through stenosed artery under the effect of slip velocity. The blood is assumed to be Newtonian. Analytical expressions for velocity profile, flow rate, wall shear stress and resistive impedance have been obtained. These expressions are computed numerically and the computational results are presented graphically. It is no...

mhd boundary layer flow of two phase model nanofluid over a vertical plate is investigated both analytically and numerically. a system of governing nonlinear partial differential equations is converted into a set of nonlinear ordinary differential equations by suitable similarity transformations and then solved analytically using homotopy analysis method and numerically by the fourth order rung...

Subcooled flow boiling in multi-microchannels can be used as an efficient thermal management approach in compact electrical devices. Highly subcooled flow boiling of HFE 7100 is studied in two microchannel heat sinks to choose a proper numerical model for simulating boiling flows in microchannels. Results of five different numerical models, including Volume of Fluid (VOF), Eulerian boiling, Eul...

This analysis investigates the distortion of flow measurement and the increase of cavitation along orifice flowmeter. The analysis using the numerical method (CFD) validated the distortion of flow measurement through the inlet velocity profile considering the convergence and grid dependency. Realizable k-e model was selected and y+ was about 50 in this numerical analysis. This analysis also est...

PURPOSE To conduct a validation study of a Doppler guide wire for potential neuroendovascular applications. METHODS A 12-MHz, 0.018-inch Doppler guide wire was evaluated in eight swine under various blood flow conditions using two types of in vivo cerebrovascular models (physiologic and arteriovenous shunting). Flow conditions were mechanically and pharmacologically altered. Doppler average p...