In this paper, a mathematical model is developed to calculate the conversion and the residence time reaction for plug flow and mixed flow in the reactors filled with cylin-drical particles using the shrinking core model. In this modeling, the size of the particles is un-chamged during the reaction. Also, the reaction rate is controlled by the gas layer resistance, the ash layer resistance, and ...

This paper evaluates the added resistance of a torpedo shape AUV, moving inside a water pipeline, due to wall effects within the tube. Today, there are long length pipelines of water or petroleum that need to regular inspection. Early detection of failure will help to prevent breakdown and avoid the huge cost of an accident. As pipelines are enclosed environments and difficult to access, pipeli...

as fetal compensation against hypoxemia progresses, the afterload on the heart and peripheral vascular resistance increases. eventually, the right heart fails, which is transmitted to the fetal venous system, causing decreased flow during late diastole or atrial contraction and increased resistance in the ductus venosus and inferior vena cava. the ductus has forward flow during atrial contracti...

This model focuses on the behavior of capillary-tissue fluid exchange system when the diameter of the capillary is less than that of red cell. In vivo and in vitro observations indicate that the width of the gap between the red cell and the vessel wall is generally small compared to the radius of the capillary for a single file flow of red cell in narrow vessel, particularly if the vessel diame...

Blood flow is modeled as non-Newtonian micropolar fluid. The non-linear governing equations of continuum and momentum in the cylindrical coordinate are being discretized using a finite difference approach and have been solved iteratively ,through Crank-Nicolson method. The blood velocity distribution, volumetric flow rate and Resistance to blood flow at the stenosis throat are computed for vari...

conclusions estelite sigma quick composite had wear resistance similar to that of nano- and microfilled composites. estelite flowable composites demonstrated similar wear resistance to that of a posterior composite. results the wear amounts of the composites are as follows in order: estelite sigma quick (1886.9 ± 518.5 μm2), estelite flow quick (2708.9 ± 578.1 μm2), estelite high flow (3206 ± 2...

Resistance to blood flow through peripheral vascular beds strongly influences cardiovascular function and transport to tissue. For a given vascular architecture, flow resistance is determined by the rheological behavior of blood flowing through microvessels. A new approach for calculating the contribution of blood rheology to microvascular flow resistance is presented. Morphology (diameter and ...

doppler ultrasound can provide important information about vascular problems through the analysis of blood flow wave-form. the purpose of this study was obtaining the normal images of color doppler and estimation of blood flow velocity parameters of femoral artery in rabbits. left and right femoral arteries of 8 healthy adult new zealand rabbits were evaluated. color and spectral doppler images...