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In this work, an inspection of the entropy generation of ternary nanofluids inside an irregular peristaltic channel resulting from heat transfer and fluid viscosity in addition to the combined effects of electric and magnetic fields is conducted. The flow is supposed to be subject to a combination of external forces such as an electric field, a magnetic field, thermal radiation, and Joule heating due to the Lorentz force. This model is a representation of the heat transfer processes of heat exchangers and some types of solar cells. Variation in channel width is an effective factor that has not been addressed by many researchers before, these assumptions are simulated by a set of nonlinear partial differential equations due to the dual effect of electric and magnetic forces and under the influence of special boundary conditions. This set of equations has been converted to non‐dimensional equations and then solved analytically to study the behavior of velocities, heat transfer, and the rate of entropy generation inside the channel under the influence of important embedded parameters. Some notable results have been reached, such as a clear growth of the entropy generation system by using more than one type of nanoparticle as a result of the improvement that occurs in the thermal and magnetic conductivity of the fluid, in addition to the increase in viscosity. The irreversibility resulting from friction and the electric and magnetic fields clearly rises in the middle and diminishes at the walls compared to the irreversibility resulting from thermal transfer. [ABSTRACT FROM AUTHOR]

The study of the boundary layer is considered one of the most important theories in the field of heat and mass transfer because of its important explanation that shows us the behavior of different surfaces while they are under the influence of the flow accompanied by different thermal forces. The study of corrugated surfaces is one of the engineering applications, such as flow in heat exchangers or solar cells or cooling processes during surface heat treatments. This model is also used in medical applications such as flow in arteries or movement in the intestines. So, the work deals with investigating the boundary layer surrounding a three‐dimensional sinusoidal pipe; the boundary layer was assumed to be filled with a hybrid nanofluid consisting of water +Cu nanoparticles as the main fluid, supported by a small concentration of Al2O3 or Ag nanoparticles. The boundary layer is described by a set of nonlinear partial differential equations due to the continuity, momentum, and energy equations, which are transformed into a set of dependently coupled nonlinear ordinary differential equations. The obtained system of equations was solved using numerical techniques. The behavior of the boundary layer under the varying types and concentrations of nanoparticles and the influence of the magnetic field has been depicted by a set of graphs and tables. With reference to some results, it is found that using 5% of nanoparticles of aluminum oxide raises the rate of cooling by 8% and using 5% of silver nanoparticles increases it by 5%. [ABSTRACT FROM AUTHOR]

The Laplace residual power series (LRPS) method uses the Caputo fractional derivative definition to solve nonlinear fractional partial differential equations. This technique has been applied successfully to solve equations such as the fractional Kuramoto–Sivashinsky equation (FKSE) and the fractional generalized regularized long wave equation (GRLWE). By transforming the equation into the Laplace domain and replacing fractional derivatives with integer derivatives, the LRPS method can solve the resulting equation using a power series expansion. The resulting solution is accurate and convergent, as demonstrated in this paper by comparing it with other analytical methods. The LRPS approach offers both computational efficiency and solution accuracy, making it an effective technique for solving nonlinear fractional partial differential equations (NFPDEs). The results are presented in the form of graphs for various values of the order of the fractional derivative and time, and the essential objective is to reduce computation effort. [ABSTRACT FROM AUTHOR]

It is believed that the use of nanoparticles to assist the blood is one of the most essential strategies to combat cancer cells that are located inside the human body. This is accomplished by enclosing the cancer cells and subjecting the regions that are affected to heat, which kills the cells and makes it possible to dispose of them in a different manner. This study offers a mathematical depiction of the flow of blood that is supported by various nanoparticles (gold-Au, iron oxide-Fe3O4, and carbon nanotube particles-SWCNTs) as it travels through a vertical artery with varied undulation while being subjected to electric and magnetic fields. The modeling process was done by a set of nonlinear partial differential equations using the Poisson–Boltzmann equation and the momentum in both directions in addition to the heat equation. Some dimensionless parameters are used to linearize the system before being solved exactly with the assistance of Mathematica software. The hypothesis that the artery ripple is irregular, and that the artery is exposed to both magnetic and electric fields, in addition to using three different types of nanoparticles, represents a novelty of this work. The impact of these factors on the flow and streamlines inside the artery is observed by a set of graphs. The results tend to an augmentation in the transversal velocity may be seen in relation to the rise in nanoparticle concentration and the Grashof number, as opposed to the impact of the magnetic field, particularly in the context of unsteady flow. Moreover, the presence of irregularities in the artery leads to an increase in both longitudinal velocity and temperature while simultaneously diminishing the waviness of both parameters. [ABSTRACT FROM AUTHOR]

The effect of variable thermal conductivity on the characteristics of heat transfer and mechanical properties of a moving surface on a Casson nanofluid flow as a coolant has been studied in this paper. We used similarity transformation method to transform the equations of the governing boundary-layer into ODE which are solved numerically using a mix of fourth order Runge-Kutta method and find root technique. Different values relevant parameters have been studied on the features of velocity, temperature, and the profiles of concentration and discussed in details for different values of various parameter as shape parameter, heat source parameter, radiation parameter, and magnetic parameter. The results were compared with previous published researches and obtained it in a good agreement and the results were tabulated. Furthermore, Nusselt number, Sherwood number, and the skin friction values with different parameters were calculated and the influence of theses physical quantities on the mechanical properties on the surface are analyzed and discussed in details. [ABSTRACT FROM AUTHOR]

Entropy analysis of an electrically conducting boundary layer of a nanofluid with microrotation elements over a moving plate is presented in this article by applying the second law of thermodynamics. Two types of nanoparticles, copper oxide (CuO) and aluminum oxide (Al2O3), are considered in addition to microstructure elements within a base fluid. The analysis is based on governing boundary layer equations associated with the linear and angular momentum as well as the energy transformed by introducing a suitable similarity transformation into a system of triple nonlinear differential equations that are solved analytically. On the physical side, this article examines the effect of the nanoparticle type and its concentration as well as the type of base fluid, whether Newtonian or non-Newtonian, on the rate of entropy generated and the rate of heat flux from the surface. This simulation involves the cooling stage of the metals during the heat treatment process, which controls the final mechanical properties of the plate, so controlling the entropy of the cooling system plays a great role on the results. The results obtained confirm that the entropy generation of the non-Newtonian fluids (fluids with microrotation elements) is higher than that of the Newtonian fluids and that the presence of nanoparticles in the cooling system increases the rate of entropy by 1–4% according to the type and concentration of the nanoparticles. [ABSTRACT FROM AUTHOR]

The present work provides an analysis of the hydromagnetic nanofluid boundary-layer flow over a rotating disk in a porous medium with a constant velocity in the presence of hall current and thermal radiation. The governing PDE system that describes the problem is converted to a system of ODE by the similarity transformation method, which solved analytically using optimal homotopy asymptotic method. The velocity profiles and temperature profiles of the boundary-layer are plotted and investigated in details. Moreover, the surface skin friction, rate of heat transfer are deduced and explained in details. [ABSTRACT FROM AUTHOR]

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The effect of thermal radiation, heat generation, suction/injection, nanoparticles type, and nanoparticle volume fraction on heat transfer characteristics and the mechanical properties of unsteady moving cylinder embedded into cooling medium consist of water with Cu, Ag, or Al2O3 particles are studied. The governing time dependent boundary layer equations are transformed to ordinary differential equations containing unsteadiness parameter, thermal radiation parameter, heat source parameter, suction/injection parameter, curvature parameter, nanoparticle volume fraction, and Prandtl number. These equations are solved numerically. The velocity and temperature profiles within the boundary layer are plotted and discussed in details for various values of the different parameters. Also the effects of the cooling medium and the external thermal forces on the mechanical properties of the cylinder are investigated. [ABSTRACT FROM AUTHOR]