The paper addresses the properties of glassforming melts in an attempt to predict the dependence of viscosity on temperature and on pressure. A review on the main viscosity models (free volume model, the Adam & Gibbs model etc.) is given. It is demonstrated that the activation energy can be expressed through the glass transition temperature Tg. The main attention is concentrated on the jump fre...

in this work, artificial neural network (ann) was utilized to develop a new model for the predictionof the kinematic viscosity of petroleum fractions. this model was generated as a function oftemperature (t), normal boiling point temperature (tb), and specific gravity (s). in order to developthe new model, different architectures of feed-forward type were examined. finally, the optimumstructure...

background: the airway surface liquid (asl), which is a fluid layer coating the interior epithelial surface of the bronchi and bronchiolesis, plays an important defensive role against foreign particles and chemicals entering lungs. objective: numerical investigation has been employed to solve two-layer model consisting of mucus layer as a viscoelastic fluid and periciliary liquid layer as a newt...

Nowadays, atomic-force microscopy plays a significant role in nanoscience and nanotechnology, and is widely used for direct measurement at atomic scale and scanning the sample surfaces. In tapping mode, the microcantilever of atomic-force microscope is excited at resonance frequency. Therefore, it is important to study its resonance. Moreover, atomic-force microscopes can be operated in fluid e...

In this study, response surface methodology (RSM) based on central composite design (CCD) was applied for investigation of the effects of ultrasonic waves, temperature and solvent concentration on viscosity reduction of residue fuel oil (RFO). Ultrasonic irradiation was employed at low frequency of 24 kHz and power of 280 W. The results showed that the combination of ultrasonic waves and solven...

in this paper, mixed convection of al2o3-eg-water nanofluid in a square lid-driven enclosure is investigated numerically. the focus of this study is on the effects of variable thermophysical properties of the nanofluid on the heat transfer characteristics. the top moving and the bottom stationary horizontal walls are insulated, while the vertical walls are kept at different constant temperature...

Rheological characteristics of Al2O3, CuO and TiO2 nano particles were investigated in oil asthe base fluid at 1 and 2 wt.%. Constitutive relations for non-Newtonian fluid were discussedbased on the power-law model. Measured viscosities of each nanofluid were used to evaluatethe power-law and consistency index. Results indicated that the nanofluid viscosity decreasedby increasing the concentrat...

The viscosity-temperature relation is determined for the water models SPC/E, TIP4P, TIP4P/Ew, and TIP4P/2005 by considering Poiseuille flow inside a nano-channel using molecular dynamics. The viscosity is determined by fitting the resulting velocity profile (away from the walls) to the continuum solution for a Newtonian fluid and then compared to experimental values. The results show that the T...