Technical computations for dependent shear rate effect on magnetized peristaltic transport of synovia with two fluid viscosity models: Arthritis treatments

Synovitis studies are the key to the treatment of most arthritis diseases in a human physique. So this study visualizes the effects of two dependent fluid viscosity models on magnet nano peristaltic transport of synovial fluid in nonuniform channel walls. Two fluid models are constructed, the first model considered that the Shear rate is dependent on fluid concentration (model-I), and the exponentially dependent viscosity on the fluid concentration is proposed as a second model (model-II). The fluid models are represented by a highly nonlinear system of partial differential equations. Joule heat, thermal radiation, and Arrhenius energy are studied as external effects. Those models are offered in a gradient mechanism, then simplified using droppings bars and using the fact of long wavelength, and low Reynolds. Pressure gradient and trapped bolus profiles and shear stress distribution as well as fluid temperature, velocity, and concentration performance are scrutinized. Analytical results are obtained in appropriate/chosen boundary conditions depending on the walls of the channel. Attracted/signified results are compared with the nearest trusted results by Khan et al. Solution intervals are sub-divided and analytically treated at each of them by multi-stage differential transform algorithms. Outcomes gratify that, joints are provided by more cushion and lubrication at high fluid temperatures. Magnetic effects are advised in rheumatoid arthritis treatments, increasing the synovial fluid temperature and allowing fluid particles to move freely inside joints.     

Impact of Soret and Dufour on MHD mixed convective flow of non-Newtonian fluid over a coagulated surface

In the present study, we investigated the steady, two-dimensional mixed convective stagnation point flow of an electrically conducting micropolar fluid due to stretching of a variable thicked surface in the attendance of viscous dissipation. The flow is incompressible and laminar. The combined heat and mass transfer features are investigated. Convective and diffusion conditions are considered. The nonlinear thermal radiation, thermo-diffusion, and diffusion thermal effects are considered. The governing partial differential equations are converted to ordinary differential equations by using the appropriate similarity transformations. The obtained nonlinear and coupled ordinary differential equations are elucidated numerically using the fourth-order Runge–Kutta based shooting technique. The influence of various nondimensional parameters on the flow field like velocity, microrotation, temperature, and concentration is examined with the assistance of graphs. Results indicate that the Dufour number has a proclivity to increase the distributions of concentration and temperature correspondingly. Also, fluid temperature and concentration enhance for increasing values of the wall thickness parameter.     

Dufour and Soret influence on MHD boundary layer flow of a Maxwell fluid over a stretching sheet with nanoparticles

An analysis has been carried out to examine the heat and mass transfer properties of a two-dimensional incompressible electrically conducting Maxwell fluid over a stretching sheet in the existence of Soret, Dufour, and nanoparticles. In many practical scenarios, such as the polymer extrusion process, the problem presented here is crucial. The flow is examined in terms of the impacts of magnetohydrodynamics and elasticity. Brownian motion and thermophoresis are incorporated into the transport equations. Using adequate similarity variables, the governing partial differential equations and related boundary conditions are non-dimensionalized. The fourth–fifth-order Runge–Kutta–Fehlberg procedure is utilized to solve the consequent transformed ordinary differential equations. The effects of various embedded thermo-physical parameters on the fluid velocity, temperature, concentration, Nusselt number, and Sherwood number have been determined and discussed quantitatively. A comparison of a special case of our results with the one previously reported in the literature shows a very good agreement. An increase in the values of Du and Sr leads to an increase in the temperature and concentration distribution. Nusselt number estimates decrease as Nb estimations increase. Furthermore, this study leads to the study of different flows of electrically conducting fluid over a stretching sheet problem that includes the two-dimensional nonlinear boundary equations.     

The axisymmetric flow of an MHD Powell–Eyring fluid with viscous dissipation and Newtonian heating condition: Keller-box method

A special investigation on the heat transfer by applying viscous dissipation and considering the Newtonian heating condition in magnetohydrodynamic Powell–Eyring fluid has been attempted. It is regarded as the flow in an axisymmetrical direction over a radially stretching surface. The converted governing system of equations is solved to obtain a closed-form solution using the Keller-box technique. The skin-friction coefficient's influence fully developed local Nusselt number is then presented graphically, and temperature profiles are sorted out for the pertinent parameters. The fluid overshoot towards the plate surface with rising magnetic field strength, hence, both the fluid velocity and the hydrodynamic border line layer thickness will fall, though, the skin-friction coefficient will increase. Various relevant results of the energy indulgence have been discussed from heating and in view of viscous dissipation phenomena. The decision with minimal cases from previous studies in the literature received confirmation of the findings.     

Multislip and Soret–Dufour influence on nonlinear convection flow of MHD dissipative Casson fluid over a slendering stretching sheet with generalized heat flux phenomenon

In the present investigation, Soret–Dufour and multislip's impact on magnetohydrodynamics (MHD) Casson fluid flow encompassing variable thermophysical features in the nonlinear convection process is analyzed. It is believed that to any effective heat and mass transfer enhancement, the relaxation of such fluid and material time along with the thermo-physical features, are well estimated. In this model, a magnetic field of nonuniform strength is applied perpendicular to the slendering sheet with variable thickness, and nonlinear convection flow is considered in this generalized heat flux examination. An appropriate similarity variable is implemented on the governing equations embedding the variable viscosity, thermal conductivity, and generalized Fourier's law to drive ordinary differential equations. Galerkin weighted residual approach is utilized to calculate the flow field among other flow characteristics. The novel flow features are discussed therein. Modified Fourier and multislip's parameters are seen to have downsized the velocity and temperature field greatly. Thermal and solutal buoyancy effects are more pronounced in nonlinear form compared to the linear model. Dufour number influences both velocity and energy fields positively but negates the concentration field, while the Soret number gives an opposing characterization.     

MHD slip flow and heat transfer of UCM fluid with the effect of suction/injection due to stretching sheet: OHAM solution

In this study, the optimal homotopy analysis (OHAM) technique has been examined to solve the laminar magnetohydrodynamic flow (MHD flow) on the upper-convected Maxwell fluid on an isothermal porous stretch surface. A study on the effects of parameters like the relaxation time, suction/injection velocity, as well as the magnetic number on velocity over a sheet was conducted and these results are compared to the corresponding previously available results. It was observed that the thickness of the boundary layer is lowered by enhancing $s$, $\beta$, and $M$ values. Opposing this, it was observed that large $\beta$ values increase the $f″\left(0\right)$ magnituIIde. It is found that OHAM is an efficient method capable of giving a greater degree of accuracy in numerical values of flow parameters even after fewer approximations.     

Terrific effect of H2 on 3D free convection MHD flow of C2H6O2H2O hybrid base fluid to dissolve Cu nanoparticles in a porous space considering the thermal radiation and nanoparticle shapes effects

In this article, the physical aspects of natural convection magnetohydrodynamic flow of Cu/Ethylene glycol-water nanofluid past a porosity vertical stretching sheet under impact of thermal radiation, shape and slip factor and suction/injection process has been analyzed using Runge- Kutta Fehlberg fifth order (RKF 5) numerical method. The influence of variable, different parameters such as nanoparticles shape factor, named hexahedron and Lamina on temperature and velocity profiles are exemplified quantitatively through graphs. Outputs demonstrate thermal radiation impact causes to produce heat and increase the temperature profile by increasing nanofluid molecules energy. Lamina shape nanoparticle has a greater effect on increasing Nusselt number (Nu) compared to hexahedron.     

The formate electrooxidation on Pt/C and PtSnO2/C nanoparticles in alkaline media: The effect of morphology and SnO2 on the platinum catalytic activity

Pt/C and PtSnO₂/C electrocatalysts with and without cubic preferential morphology were used for formate electrooxidation reaction (FER) in alkaline medium. The synthesis of catalysts was carried out by alcohol reduction method using KBr as a shape directing agent (Bromide Anion Exchange method - BAE). The X-ray diffraction (XRD) showed characteristic peaks of the Pt face-centered cubic (FCC) structure, as well as cassiterite SnO₂. The Transmission Electron Microscopy (TEM) and Scanning Transmission Electron Microscopy (STEM) micrographs show SnO₂ dispersed onto carbon support and adjacent to the Pt nanoparticles (NPs), as well as cubic Pt NPs. The cyclic voltammetry (CV) measurements show that the current density peak for FER on Pt/C (100) is 2.40 times higher than on Pt/C polycrystalline (poly). The current density at end of chronoamperometry (CA) analysis on PtSnO₂/C poly was 1.33 and 5.29 times higher than on Pt/C (100) and Pt/C poly, respectively. The presence of SnO₂ and the (100) facets of platinum cubic morphology might prevent platinum surface deactivation caused by intermediates formed during the FER process.     

Giant cane (Arundo donax L.) for biogas production: The effect of two ensilage methods on biomass characteristics and biogas potential

Arundo donax L. is a perennial plant that can substitute for traditional energy crops to produce biogas, reducing costs because of its high biogas yield per Ha cultivated and low agronomic and energetic inputs. Nevertheless, Arundo donax biomass needs to be ensiled to be preserved and used. Because no full-scale data exist about A. donax ensilage and the effect of this process on potential biogas production, in this work two different ensiling techniques, i.e. trench and silo-bag ensiling, were performed at full scale, and the processes studied for 200 days. Results obtained indicated that A. donax could be successful ensiled by using the two approaches. Ensilage proceeded by fermentation of organic acids already present in the biomass, i.e. malic and oxalic acids that were degraded, giving volatile fatty acid accumulation. This was different from corn ensiling characterized by starch fermentation to lactic acids. Biological processes determined a loss of the potential biomethane production, namely −20.1% and −7.6% for trench and silo-bag, respectively. Taking into consideration biomethane yield per Ha and ensilage losses, potential biomethane losses of 5000 Nm³ CH₄ Ha⁻¹ for trench silage and of 2000 Nm³ CH₄ Ha⁻¹ for silo bag, were estimated, respectively. Nevertheless, taking into consideration the higher biomass and biomethane yields Ha⁻¹ in comparison with the other energy crops, A. donax still remained more efficient and cheaper than traditional energy crops in producing biogas.