An eddy viscosity model can be used as a computationally tractable alternative to that of the Navier-Stokes equations. Model errors immediately become a concern when considering such an approach, and quantifying this error is essential to understanding and using model predictions within an engineering design process. In this paper, sensitivity analysis is presented for a subgrid eddy viscosity ...

Background: The airway surface liquid (ASL), which is a ï‌‚uid 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 New...

OBJECTIVES The atherosclerotic process in arteries is correlated with the local wall shear stress (WSS). Plaque development particularly occurs in regions with recirculation (ie, where the WSS oscillates). We investigated the effects of non-Newtonian blood viscosity, variations in flow rate, and vessel diameter on wall phenomena in a carotid bifurcation model. MATERIALS AND METHODS The flow t...

The influence of temperature, mean nanoparticle size and the nanoparticle concentration on the dynamic viscosities of nanofluids are investigated in an analytical method followed by introduction of modified equations for calculating the nanofluids’ viscosities. A new correlation is developed for effective viscosity based on the previous model where the Brownian movement of the nanoparticles is co...

aloe vera is a plant of the liliaceae family with a brilliant history in disease treatment. in addition to the pharmaceutical, cosmetic, and health care industries, this plant is used in food industry due to having various nutrients such as amino acids and various vitamins or anti-bacterial compounds. the purpose of this study was to investigate the effects of variables such as temperature, tim...

The present study attempted deriving and solving the falling- cylinder governing equations for power law model non-Newtonian fluids. Based on this theoretical study, a novel falling- cylinder rheometer (FCR) was designed and constructed to measure the Theological properties of non-Newtonian fluids. Different falling cylinders with predesigned densities were used to determine the apparent viscos...

various scaling methods such as relative viscosity, peclet and reynolds scaling were used to find the best scaling law. scaling and modeling of the flow curves of various model emulsions consist of tragacanth gum (tg) (0.5, 1 % wt), oleic acid (5, 10% v/v) and wpi (2, 4 % wt) were investigated and the best models were selected. as these emulsions are non-newtonian, they do not obey the usual, si...

Purely dissipative eddy–viscosity subgrid models have proven very successful in large–eddy simulations (LES) at moderate resolution. Simulations at coarse resolutions where the underlying assumption of small–scale universality is not valid, warrant more advanced models. However, non-eddy viscosity models are often unstable due to the lack of sufficient dissipation. This paper proposes a simple ...