An axial flow cyclone for removing nanoparticles was tested for collection efficiency. Data were validated numerically in vacuum conditions of several Torrs, with flow rates of 0.35-0.57 slpm. The experimental cutoff aerodynamic diameter of the cyclone ranged from 21.7 to 49.8 nm. A 3-D numerical simulation was conducted first to calculate detailed flow and pressure fields, then a Brownian Dyna...

We consider the problem of blood flow in an artery and in the presence of an overlapping stenosis, which is also assumed to have an axisymmetric shape. The blood flow in the arterial tube is assumed to be a suspension of red cells in plasma. The present formulation makes use of the variable fluid viscosity modeling that takes into account the amount of red cells in the blood fluid flow system. ...

In this study, the positive and negative power-off process of a bi-directional full-flow pump is investigated by model tests numerical simulations, results show that under steady conditions, head in direction larger than direction. The slower process. clearance backflow rate continues to drop during until it remains stable runaway condition. causes vortex at impeller inlet size gradually decrea...

In this study, the convective heat transfer and pressure drop in laminar flow of Al2O3/water and CuO/water nanofluids through square and triangular cross-sectional ducts have been numerically investigated using new technique. It has been assumed that there is constant heat flux boundary condition at walls. In addition, to include the presence of nanoparticles, the dispersion model has been used...

In a polymer membrane fuel cell more than half of the chemical energy of hydrogen is converted to heat during generation of electricity. This causes an increase in the cell temperature. The Cooling field design has a significant role in cell cooling. The cell's performance and stability are reduced due to inappropriate heat dissipation. In this paper, the cooling flow and heat transfer in cooli...

in the present study the effect of curvature ratio and coil pitch for tio2/water nanofluid laminar flow on heat transfer behavior and pressure drop through helical coils with different geometries was investigated experimentally. the tio2/water nanofluids at 0.25% to 2% particle volume concentrations have been prepared by using a two-step method. the experiments were performed for coils with cur...

In this paper, a comprehensive study on the performance of parallel plate and rectangular micro channel counter flow heat exchangers is presented. The geometrical parameters of the two configurations are optimized for a given heat transfer rate, effectiveness and pressure drop. In case of rectangular micro channel counter flow heat exchanger, a reduced order model is developed first in which re...

Buckling analysis of thin cylindrical shells is very important due to their production process.  Usually longitudinal and transversal stiffeners are used to increase the buckling stiffness. In this paper, considering a thin cylindrical shell with longitudinal and transversal ribs subjected to axial force and lateral pressure, the influence of different aspect of axial force to lateral pressure ...