Non-Coaxially Rotating Motion in Casson Martial along with Temperature and Concentration Gradients via First-Order Chemical Reaction

The effect of non-coaxial rotation on the transport of mass subjected to first-order chemical reaction is studied analytically. The effects of thermal radiation, buoyancy, constructive and destructive chemical reactions along with Casson fluid in rotating frame are discussed. Time evolution of primary and secondary velocities, energy and solute particles are analyzed. The behavior of flow under the variation of intensity of magnetic field is also investigated. Evolutionary behavior of primary velocity is opposite to the evolutionary behavior of secondary velocity. The impact of buoyant force on primary velocity is opposite to the role of buoyant force on the secondary velocity. The evolutionary behavior of temperature is also examined and a remarkable enhancement in temperature is noticed. Thermal radiation causes the fluid to be cooled down as heat energy is escaped by thermal radiation. Evolutionary behavior of concentration is also analyzed and an increasing of concentration versus time is noted. Destructive chemical reaction results a remarkable reduction in the concentration and vice versa for generative chemical reaction.

Exploring the nanomechanical concepts of development through recent updates in magnetically guided system

This article outlines an analytical analysis of unsteady mixed bioconvection buoyancy-driven nanofluid thermodynamics and gyrotactic microorganisms motion in the stagnation domain of the impulsively rotating sphere with convective boundary conditions. To make the equations physically realistic, zero mass transfer boundary conditions have been used. The Brownian motion and thermophoresis effects are incorporated in the nanofluid model. Magnetic dipole effect has been implemented. A system of partial differential equations is used to represent thermodynamics and gyrotactic microorganisms motion, which is then transformed into dimensionless ordinary differential equations. The solution methodology is involved by homotopy analysis method. The results obtained are based on the effect of dimensionless parameters on the velocity, temperature, nanoparticles concentration and density of the motile microorganisms profiles. The primary velocity increases as the mixed convection and viscoelastic parameters are increased while it decreases as the buoyancy ratio, ferro-hydrodynamic interaction and rotation parameters are increased. The secondary velocity decreases as viscoelastic parameter increases while it increases as the rotation parameter increases. Temperature is reduced as the Prandtl number and thermophoresis parameter are increased. The nanoparticles concentration is increased as the Brownian motion parameter increases. The motile density of gyrotactic microorganisms increases as the bioconvection Rayleigh number, rotation parameter and thermal Biot number are increased.

Characterization of carbonate rocks using seismic wave for tunnel design stability

The design and construction of a tunnel depends on the mechanical properties of the rock mass around the tunnel. Seismic method can be used to characterize the dynamic properties of rocks. The technique is mostly conducted in geophysical surveys and geotechnical investigations. The method utilizes reflected sound waves that can be used to describe the dynamic properties of rocks. Physical properties of carbonate rocks such as water content, density, hardness, permeability, porosity, wave velocity and abrasivity can be assessed and estimated using P-wave velocity. One of the important characteristics in rock is its ability to remain stable. In this research, seismic refraction survey was applied to measure the strength of carbonate rocks for tunnel stability design. The findings revealed that the regression between the primary velocity and the uniaxial compressive strength R2 was 0.8592, indicating that the rock was firm and solid. Observation by physical visual test showed that the rock samples with yellowish-grey and light grey colours were categorized in the weathering grade II and III, respectively. The results have concluded that the rocks in the proposed area met the full requirements for tunnelling construction.

A stabilizer free WG method for the Stokes equations with order two superconvergence on polytopal mesh

<p style='text-indent:20px;'>A stabilizer free WG method is introduced for the Stokes equations with superconvergence on polytopal mesh in primary velocity-pressure formulation. Convergence rates two order higher than the optimal-order for velocity of the WG approximation is proved in both an energy norm and the <inline-formula><tex-math id="M1">\begin{document}$ L^2 $\end{document}</tex-math></inline-formula> norm. Optimal order error estimate for pressure in the <inline-formula><tex-math id="M2">\begin{document}$ L^2 $\end{document}</tex-math></inline-formula> norm is also established. The numerical examples cover low and high order approximations, and 2D and 3D cases.</p>

Magnetic Rotating Flow of a Hybrid Nano-Materials Ag-MoS2 and Go-MoS2 in C2H6O2-H2O Hybrid Base Fluid over an Extending Surface Involving Activation Energy: FE Simulation

Numeric simulations are performed for a comparative study of magnetohydrodynamic (MHD) rotational flow of hybrid nanofluids (MoS2-Ag/ethyleneglycol-water (50–50%) and MoS2-Go/ethyleneglycol-water (50–50%)) over a horizontally elongated plane sheet. The principal objective is concerned with the enhancement of thermal transportation. The three-dimensional formulation governing the conservation of mass, momentum, energy, and concentration is transmuted into two-dimensional partial differentiation by employing similarity transforms. The resulting set of equations (PDEs) is then solved by variational finite element procedure coded in Matlab script. An intensive computational run is carried out for suitable ranges of the particular quantities of influence. The primary velocity component decreases monotonically and the magnitude of secondary velocity component diminishes significantly when magnetic parameter, rotational parameter, and unsteadiness parameter are incremented. Both the primary and secondary velocities are smaller in values for the hybrid phase Ag-MoS2 than that of hybrid phase Go-MoS2 but the nanoparticle concentration and temperature are higher for hybrid phase Ag-MoS2. The increased values of parameters for thermophoresis, Brownian motion, shape factor, and volume fraction of ϕ2 made significant improvement in the temperature of the two phases of nano liquids. Results are also computed for the coefficients of skin friction(x, y-directions), Nusselt number, and Sherwood number. The present findings manifest reasonable comparison to their existing counterparts. Some of the practical engineering applications of the present analysis may be found in high-temperature nanomaterial processing technology, crystal growing, extrusion processes, manufacturing and rolling of polymer sheets, academic research, lubrication processes, and polymer industry.

Hall and Ion Slip Effects on Mixed Convection Flow of Eyring-Powell Nanofluid over a Stretching Surface

The purpose of this research is to inspect the mixed convection flow of Eyring-Powell nanofluid over a linearly stretching sheet through a porous medium with Cattaneo–Christov heat and mass flux model in the presence of Hall and ion slip, permeability, and Joule heating effects. Proper similarity transforms yield coupled nonlinear differential systems, which are solved using the spectral relaxation method (SRM). The story audits show that the present research problem has not been studied until this point. Efficiency of numerous parameters on velocity, temperature, and concentration curves is exposed graphically. Likewise, the numerical values of skin friction coefficients, local Nusselt, and Sherwood numbers are computed and tabulated for some physical parameters. It is manifested that fluid velocities, skin friction coefficients, local Nusselt, and Sherwood numbers promote with the larger values of Eyring-Powell fluid parameter ε. It is also noticed that primary velocity promotes with larger values of mixed convection parameter λ, Hall parameter βe, and ion slip parameter βi, while the opposite condition is observed for secondary velocity, temperature, and concentration. Furthermore, comparative surveys between the previously distributed writing and the current information are made for explicit cases, which are examined to be in a marvelous understanding.

Adomian decomposition method for combined effect of Hall and ion-slip on mixed convection flow of chemically reacting Newtonian fluid in a microchannel with heat absorption/generation

In this work, theoretical analysis is carried out on fully developed hydromagnetic flow of heat generating/absorbing fluid in a vertical microchannel in the presence of Hall and ion-slip effects. The governing coupled flow equations are obtained in dimensional form and thereafter simplified by employing some similarity transformation variables and quantities. The transformed coupled equations are solved by adopting the Adomian Decomposition Method (ADM) and their solution represented in closed form. Interesting influences of some active parameter on different flow features are shown using line graphs and Table. The numerical values for the results obtained in this work using ADM were validated with results obtained from existing benchmark. Results from the analysis reveal that in the existence of heat generation/absorption, the primary velocity and the temperature distribution could be enhanced by growing the ion-slip and Hall current parameter, whereas its influence on velocity is contrary along the secondary direction.

Radiative Effects on Unsteady MHD Couette Flow through a Parallel Plate with Constant Pressure Gradient

In this paper, the unsteady MHD Couette flow through a porous medium of a viscous incompressible fluid bounded by two parallel porous plates under the influence of thermal radiation and chemical reaction is investigated. A uniform suction and injection are applied perpendicular to the plates while the fluid motion is subjected to the constant pressure gradient. The transformed conservation equations are solved analytically subject to physically appropriate boundary conditions by using the Eigenfunction expansion technique. The influence of some emerging non-dimensional parameters namely, pressure gradient, suction parameter, radiation parameter, and Hartman number are examined in detail. It is observed that the primary velocity is increased with increasing pressure gradient while the increase in radiation parameter leads to adecrease in the thermal profile of the flow.

Adomain computation of radiative-convective bi-directional stretching flow of a magnetic non-Newtonian fluid in porous media with homogeneous–heterogeneous reactions

In the present communication, the laminar, incompressible, hydromagnetic flow of an electrically conducting non-Newtonian (Sisko) fluid over a bi-directional stretching sheet in a porous medium is studied theoretically. Thermal radiation flux, homogeneous–heterogeneous chemical reactions and convective wall heating are included in the model. The resultant nonlinear ordinary differential equations with transformed boundary conditions via similarity transformation are then solved with the semi-analytical Adomain Decomposition Method (ADM). Validation with earlier studies is included for the nonradiative case. Extensive visualization of velocity, temperature and species concentration distributions for various emerging parameters is included. Increasing the magnetic field and inverse permeability parameter is observed to decelerate both the primary and secondary velocity magnitudes whereas they increase temperatures in the regime. Increasing sheet stretching ratio weakly accelerates the primary flow throughout the boundary layer whereas it more dramatically accelerates the secondary flow near sheet surface. Temperature is consistently reduced with increasing stretching sheet ratio whereas it is strongly enhanced with greater radiative parameter. With greater Sisko non-Newtonian power-law index the primary velocity and temperature are decreased whereas the secondary velocity is increased. Increasing both homogenous and heterogeneous chemical reaction parameters is found to weakly and more strongly, respectively, deplete concentration magnitudes whereas greater Schmidt number enhances them.