Density functional theory and computer simulation are used to investigate sedimentation equilibria of colloid-polymer mixtures within the Asakura-Oosawa-Vrij model of hard sphere colloids and ideal polymers. When the ratio of buoyant masses of the two species is comparable to the ratio of differences in density of the coexisting bulk (colloid) gas and liquid phases, a stable "floating liquid" p...

Atomization of liquid jets in gaseous crossflows has many natural and industrial applications, for example, fuel atomization gas turbine engines, rocket film cooling, and, recently, suspension solution precursor plasma spraying processes the development advanced coatings. Viscosity density medium may significantly vary applications such as spraying, which can affect instability waves on jet col...

A liquid piston concept is proposed to improve the efficiency of gas compression and expansion. Because a liquid can conform to an irregular chamber volume, the surface area to volume ratio in the gas chamber can be maximized using a liquid piston. This creates near-isothermal operation, which minimizes energy lost to heat generation. A liquid piston eliminates gas leakage and replaces sliding ...

Upgrading of cracked PFO (Pyrolysis fuel oil) for production of fuels, such as gasoline and light gasoil, was carried out in a semi batch reactor. Two different kinds of mesoporous and microporous catalysts, MCM-41 and ZSM-5, were used. Modification methods, such as ion exchange and impregnation with Fe and Ti, were done for tuning the acidity of the catalyst. XRD, FT-IR, and XRF analyzes were ...

A proper understanding of reservoir fluid phase behavior is the first crucial step in the development and production of an oil/gas field. This paper addresses the challenges and errors associated with the fluid sampling that may arise before, during and after the sampling operation. For this aim, DST and PVT data of exploration and production wells of a supergiant offshore gas condensate reserv...

In a liquid containing gas bubbles the speed of sound is less tham that in each phase separately. Using the equations of motion for a hõmogeneous liquid containing gas bubbles it is shown that the dominating attenuation of an infinitesimal disturbance is that due to the second viscosity. In the propagation of a finite compressive disturbance an expression for the time required for the disturban...

this work is a primary achievement in studying the co2 and n2–oil systems. to predict gas-liquid relative permeability curves, a shan-chen type multicomponent multiphase lattice boltzmann model for two-phase flow through 2d porous media is developed. periodic and bounce back boundary conditions are applied to the model with the guo scheme for the external body force (i.e., the pressure gradient...

Gas holdup and mixing time were characterized in a forced circulation internal loop draft-tube reactor (unaerated aspect ratio≈ 6, downcomero-riser cross-sectional area ratio = 0.493) as functions of the forced liquid superficial velocity in the riser (ULr) and the gas superficial velocity in he riser (UGr). Data were obtained in air–water system. The operation ranges were 0≤ULr ≤ 0.051 m/s and...

water contamination due to the wide variety of pesticides used in agriculture is a global environmental pollution problem. in order to reach at sub-î¼gl-1 levels of detection, an efficient extraction technique is required. a simple, fast and economical method, dispersive liquid-liquid micro extraction (dllme), followed by gas chromatography-mass spectrometry was assessed for determining endosul...

The formation of bubbles by flow focusing of a gas and a liquid in a rectangular channel is shown to depend strongly on the channel aspect ratio. Bubble breakup consists in a slow linear 2D collapse of the gas thread, ending in a fast 3D pinch-off. The 2D collapse is predicted to be stable against perturbations of the gas-liquid interface, whereas the 3D pinch-off is unstable, causing bubble po...