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The purpose of this study is to investigate the flow of liquid (specifically water) supported by three different types of nanoparticles (copper, silver, and aluminum oxide) in a slanted microcorrugated pipe with varying diameters and wave displacements. This model fulfills several key uses in the fields of environmental and water treatment, such as improving fluid mixing within inclined microchannels to boost the effectiveness of filtration and separation processes and designing inclined channels with ripples to better mix waste materials and more effectively separate different components. In this perception, we analyzed a model for the fluids flow inside the microchannel with the electromagnetic field (EMF) effects and pressure variation in the conduit under the external influence of thermal radiation and heat source which did not appear in the last published literature. The analytical techniques with assistance of mathematical software were used to solve the main governing equations such as Poisson, momentum, and energy equations and then deduce the heat transfer rate at the peristaltic conduit surfaces and the system's ideal entropy. The results of the model simulation suggested that a number of factors could have a big influence on how thermal systems are built. It was claimed that the irreversibility resulting from friction and Joule heating, as opposed to thermal irreversibility, controls the system's entropy buildup more tightly. Furthermore, the alteration of the conduit's form and geometry resulted in a substantial enhancement in the heat transfer rate at its bottom wall, ranging from 20% to 600%. Despite numerous studies, an accurate model regarding the mechanism of the liquid's flow supported by tri‐nanoparticles in an inclined microcorrugated conduit enclosing variable diameters and wave shifts is far from being understood. [ABSTRACT FROM AUTHOR]

The present investigation deals with the effects of biodegradable, biodurable and polymer-free coating of a stent on the release mechanism of the drug in a porous medium. The Brinkman equations for the interstitial fluid, the unsteady convection-diffusion-reaction equation for the transport of free drug in the tissue and the unsteady reaction equations for the bound as well as the internalized drug have been considered. In the coating, the transport of drug has been modeled as a diffusion process. Effects of different percentages of the embedment, convection and various coating properties of the stent on the transport of free drug, its retention and the internalization of the bound drug have been studied. Immersed Boundary Method (IBM) in the staggered grid formulation (IBM-MAC) has been used to tackle numerically the system of nonlinear governing equations. Simulated results predict the fastest release of drug from a biodegradable coating, but the averaged concentrations of all drug forms do reach a quasi-steady state in case of a biodurable coating irrespective of the degrees of embedment. Moreover, for all embedment levels of the stent, a biodegradable coating is superior to that of biodurable and polymer-free coating in the presence/absence of convection for larger times, but this superiority is lost for smaller times. Unlike biodurable coating, it is also predicted that the more the embedment level does not necessarily imply the more the effectiveness of delivery for biodegradable and polymer-free coatings of a stent. [ABSTRACT FROM AUTHOR]

The simultaneous effect of flexible wall and multiple stenoses on the flow and mass transfer of blood is investigated through numerical computation and simulations. The solution is obtained using the Marker and Cell technique on an axisymmetric model of Newtonian blood flow. The results compare favorably with physical observations where the pulsatile boundary condition and double stenoses result in a higher pressure drop across the stenoses. The streamlines, the iso-concentration lines, the Sherwood number, and the mass concentration variations along the entire wall segment provide a comprehensive analysis of the mass transport characteristics. The double stenoses and pulsatile inlet conditions increase the number of recirculation regions and effect a higher mass transfer rate at the throat, whereby more mass is expected to accumulate and cause further stenosis. [ABSTRACT FROM AUTHOR]