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There are large mines of natural bitumen around the world and low price make it a good opportunity for increasing of industrial usage of this material. This paper studies the possibility of producing new material in oxide bitumen properties range from combination of natural bitumen and pyrolysis fuel oil. To achieve this goal first used some experiments to determine the physical properties of raw materials and then after combining more natural bitumen and pyrolysis fuel oil in different samples some test including penetration, softening point and ductility test have been done and results have been compare to ASTM and BS standard. Ultimately seen this combination can produce bitumen with R115/15 and R95/25 grade.

In this research a two dimensional, single phase, and isothermal model is developed to investigate the effects of eccentric catheterization on blood flow characteristics in a tapered and stenosis artery which is complex system. The model conducted by assuming that the blood is as Newtonian and incompressible fluid and the temperature effects are also neglected. The results clearly show that the axial velocity and the magnitude of the wall shear stress distribution are higher for eccentric catheter than that for concentric one. Also, the resistance impedance gives the reverse trend of the wall shear stress with respect to the taper angle where blood can flow freely through diverging vessel but in the case of eccentric catheter is less than that of the concentric one when the radius of catheter is considered. In addition, the trapping appears near the wall of catheter and the trapped bolus increases in size as the radius of catheter increases.

Mesh independence analysis is one of the most crucial steps in any CFD problem. The aim of this study was to investigate the most commonly used variables employed for grid independency studies in a typical PEMFC and to find possibly the most effective variables that may be decisive in a PEMFC grid independence test. Herein, a three-dimensional (3-D), steady state, non-isothermal computational fluid dynamics (CFD) model of a serpentine channel proton exchange membrane fuel cell (PEMFC) was developed. The present model includes various conservation equations that are dominant in a typical PEMFC: the mass, momentum, species, charge, and energy equations, which are coupled with the electrochemical model. The numerical results indicate that much more care should be taken while obtaining a mesh independence solution for CFD studies in PEMFC systems. Based on our findings in this study, it was demonstrated that employment of merely the polarization curve (current-voltage), especially only in a given specific point, was not sufficient to carry out the mesh independence tests for CFD studies in PEMFCs. In addition, it was observed that the average volumetric hydrogen concentration inside the catalyst layer on the anode side has a more significant role to check the grid independency tests.