Abstract. In this paper, a Cascaded Lattice Boltzmann Method with second order slip boundary conditions is developed to study gas flows in a microchannel in the slip and transition flow regimes with a wide range of Knudsen numbers. For the first time the effect of wall confinement is considered on the effective mean free path of the gas molecules using a function with nonconstant Bosanquet para...

Transportation of unrefined crude oil from the production unit to a refinery or large storage area by a pipeline is difficult due to the different properties of crude in various areas. Thus, the design of a crude oil pipeline is a very complex and time consuming process, when considering all the various parameters. There were three very important parameters that play a significant role in the t...

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...

Flow velocity profiles of micro counter-current flow of aqueous and butylacetate phases in a microchannel having a width of 100 microm were measured by micro particle image velocimetry. In order to analyze the hydrodynamic characteristics of the counter-current flow, we derived a simple analytical model for the velocity profile. When flow rates of the aqueous and organic phases were 0.2 and 0.1...

Four multiphase flow models or correlations (Duns & Ros, Hagedorn & Brown, Orkiszewski, and Beggs & Brill) are currently available in Hydra for predicting the pressure profile in a well. The range of applicability of the multiphase flow models is dependent on several factors such as, tubing size or diameter, oil gravity, gas-liquid ratio, and, two-phase flow with or without water-cut. The effec...

The measurement of fluid flows is an emerging field for optical flow computation. In a number of such applications, a tracer is visualized with modern digital cameras. Due to the projective nature of the imaging process, the tracer is integrated across a velocity profile. In this contribution, a novel technique is presented that explicitly models brightness changes due to this integration. Only...

The aim of this work is to determine the supersonic nozzle profiles used in propulsion, for the launchers or embarked with the satellites. This design has as a role firstly, to give a important propulsion, i.e. with uniform and parallel flow at exit, secondly to find a short length profiles without modification of the flow in the nozzle. The first elaborate program is used to determine the prof...

the purpose of this research is to numerically investigate the interaction of pulsatile flow of blood with an axisymmetric artery in various percentages of stenosis. the carreau non-newtonian model and the generalized maxwell rheological model were used to model the blood fluid and the viscoelastic wall of arterial, respectively. the innovation of the present research is modeling of viscoelasti...

background: to determine whether islamic fasting would change cerebral blood flow during ramadan. methods: the study group comprised 20 subjects (16 males and 4 females) on a regimen of 1 month food and water intake restriction, according to islamic fasting ritual. subjects were evaluated for cerebral bolo flow through a middle cerebral artery (mca) by means of transcranial doppler (tcd), the d...