in this paper, direct numerical simulation of two-phase incompressible gas-liquid flow for simulation of bubble motion in a microtube is presented. microtube radius is 10 µm. the interface is tracked using volume of fluid (vof) method with continuous surface force (csf) model. the flow is solved using a finite volume scheme, based on piso algorithm. numerical simulation is performed on a axisym...

the objective of this research is to develop an accurate numerical method to be used in showing the deformation of a liquid fuel droplet in a convective field. to simultaneously solve the internal liquid droplet flow field as well as the external gas phase flow field, a nonstaggered rectangular grid system without any coordinate transformation is used. transition from the gas field to the liqui...

an air–assisted liquid–liquid microextraction method for the extraction and preconcentration of trace amounts of some synthetic phenolic antioxidants in biological fluids followed by their determination by gas chromatography–flame ionization detection has been reported. in this method the target analytes are extracted into a few microliters of carbon tetrachloride (extraction solvent) from an a...

background: a new microextraction method named dispersive liquid-liquid microextraction (dllme) for determination of chloroform in pool water and blood of swimmers after swimming is described. methods: this method was performed based on coupling dispersive liquid-liquid microextraction (dllme) with gas chromatog­raphy-mass spectrometry (gc-ms). methanol and trichloroethylenes were used as the d...

The objective of this work is to develop deep theoretical methods that are based on the solution of the integral boundary layer equations for investigating film cooling in liquid rocket engine. The integral model assumes that heat is transferred from hot free stream gas to the liquid film both by convection and radiation. The mass is transferred to the free srteam gas by the well-known blowing ...

In this study, the use of the three-layer feed forward neural network has been investigated for estimating of infinite dilute diffusion coefficient ( D12 ) of supercritical fluid (SCF), liquid and gas binary systems. Infinite dilute diffusion coefficient was spotted as a function of critical temperature, critical pressure, critical volume, normal boiling point, molecular volume in normal boilin...

Understanding the kinetics of gas hydrate formation is essential to model and predict the hydrate formation (or dissociation) process. In the present paper, we investigated the formation of pure propane gas hydrate as a former gas. In this regard, several experiments were conducted to measure the rate of hydrate formation under various pressures (410 to 510 kPa) and temperatures (274 K to 277 K...

The internal flow circulation dynamics of a liquid drop moving in a co- or counter-flowing gas stream has been numerically studied. The present work is concerned with the time accurate numerical solution of the two phase flow field at the low Mach number limit with an appropriate volume tracking method to capture motion and deformation of a liquid drop. It is shown that relative velocity betwee...

Sieve trays are widely used in the gas- liquid contactors such as distillation and absorption towers. In this article, a three-dimensional, two phase CFD model using Euler-Euler framework was developed to simulate a distillation tower with two sieve trays. Hydrodynamic simulation of air and water system in different rates of gas phase was carried out and velocity distribution parameters, clear ...

Gas-lift pumps are devices for lifting liquid phase incorporating the gas phase to be injected in the bottom of liquid column. They are widely used in various industrial applications such as oil extracting in petroleum industries. Gas-liquid flow being the main part of the flow through these systems, flowing in vertical pipes of gas-lift pumps has different regimes namely bubbly, slug, chur...