Non-Newtonian electromagnetic fluid flow through a slanted parabolic started Riga surface with ramped energy

The present study deals with the implications of non-Newtonian fluid via a slanted parabolic started surface with ramped energy. In addition, the characteristics of electrically conducting viscoelastic liquid moving across the Riga surface are investigated systematically, emphasized within the time-dependent concentration and temperature variations. The mathematical model is made possible by enforcing momentum and heat conservation principles in the format of partial differential equations (PDEs). Heat considerations are emphasized with respect to radiant heat influx. Similarity characteristics are leveraged to convert PDEs to ordinary differential equations. The Laplace transform method is used to find the exact solutions for the obtained differential configuration. The effect of flow on associated patterns is depicted graphically and with tables. Furthermore, fluctuation in relevant engineering parameters such as wall shear stress, temperature, and mass variability on the surface is measured. The range of parameters selected is as follows: $\psi [0.1-1]$, $Pr[0.71-10]$, $Sc[0.16-2.01]$, $Gr=Gc[5-20]$, $E[1-5]$, and $R[2-10]$. The analytical and numerical solutions are validated and in good agreement. It is worth reporting that the improved Hartmann number and thermal radiation values boost velocity dispersion and skin friction. As expected, respectively, energy and mass transfer rates are escalated with large values of Prandtl number and Schmidt number.     

FHD flow and heat transfer over a porous rotating disk accounting for Coriolis force along with viscous dissipation and thermal radiation

The prime concern of the current findings includes the effect of viscous dissipation and nonlinear thermal radiation on the study of ferrofluid flow and heat transfer past a porous rotating disk. The time-independent flow of incompressible ferrofluid is modeled for the considered geometry, and via similarity transformations, the given system is converted to a dimensionless system of the nonlinear ordinary differential equations. Here, the findings are explored computationally with help of Maple software. The study exhibits the effect of the involved emerging parameters: the interaction parameter $B$, Prandtl number $Pr$, rotation parameter $R$, radiation parameter $Qr$, Eckert number $Ec$, and these are discussed graphically. Moreover, the numerical values of heat transfer rate and skin frictions are also presented in tabular form. From the perspective of numerical findings, it is perceived that the radial flow is dominant when we increase the rotation of the disk. Furthermore, the magnitude of magnetic-fluid temperature is enhanced with the surge in the magnetic field, viscous dissipation, and thermal radiation mechanism. Finally, the current research can successfully fill a gap in the existing literature.     

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.     

A mathematical simulation of unsteady MHD Casson nanofluid flow subject to the influence of chemical reaction over a stretching surface: Buongiorno's model

In this study, unsteady boundary layer flow with Casson nanofluid within the sight of chemical reaction toward a stretching sheet has been analyzed mathematically. The fundamental motivation behind the present examination is to research the influence of different fluid parameters, in particular, Casson fluid $\beta (0.2\le \beta \le 0.4)$, thermophoresis $Nt(0.5\le Nt\le 1.5)$, magnetohydrodynamic $M(3.0\le M\le 5.0)$, Brownian movement $Nb(0.5\le Nb\le 2.0)$, Prandtl numberty, unsteadiness parameter $A(0.10\le A\le 0.25)$, chemical reaction parameter $\gamma (0.1\le \gamma \le 0.8)$, and Schmidt number $Sc(1.0\le Sc\le 3.0)$ on nanoparticle concentration, temperature, and velocity distribution. The shooting procedure has been adopted to solve transformed equations with the assistance of Runge–Kutta Fehlberg technique. The impact of different controlling fluid parameters on flow, heat, and mass transportation are depicted in tabular form and are shown graphically. Additionally, values of skin friction coefficient, Nusselt number, and Sherwood number are depicted via tables. Present consequences of the investigation for Nusselt number are related with existing results in writing by taking $Nb=0$ and $Nt=0$ where results are finding by utilization of MATLAB programming. Findings of current research help in controlling the rate of heat and mass aspects to make the desired quality of final product aiding manufacturing companies and industrial areas.     

Influence of a curved conical turbulator on heat transfer augmentation in a helical double-pipe heat exchanger

The rate of heat transfer in helical pipes is much more than straight pipes. In the present study, heat transfer and fluid flow in a double-coil heat exchanger with an innovative swirl generator with a curved structure in the inner channel (hot side) are studied, numerically. The proposed turbulator has a curved structure and 12 blades to produce swirl flows. Also, two holes are considered at the semi-conical part of the turbulator. The effects of geometrical parameters of the proposed turbulator including the inner radius of the turbulator and the radius of the turbulator's holes are evaluated. Results indicate that the maximum effectiveness belongs to the case with inner diameter of the turbulator and radius of turbulator' holes equal to 19 and 3.6 mm, respectively, at $\dot{m}=0.008\mathrm{k}\mathrm{g}\mathrm{/}\mathrm{s}$. Also, the generated swirl flows by the turbulator has a significant influence on heat transfer augmentation. Furthermore, a high inner radius of the turbulator leads to an increase in heat transfer rate and effectiveness, consequently. As a result, by increasing the inner radius of turbulator by 26.7%, the effectiveness rises by 80% (maximum at $\dot{m}$ = 0.008 kg/s). Increasing the radius of turbulator's hole by 133.34% leads to an growth in effectiveness of about 50% (maximum at $\dot{m}$ = 0.058 kg/s).     

Influence of heat source on viscous dissipative hydromagnetic fluid flow in a permeable vertical channel subjected to time-periodic boundary conditions

Unsteady heat-generating natural convective viscous dissipative fluid flow through a permeable steady-periodic vertical channel in the presence of heat source is studied. The coupled partial differential governing equations of the problem are simplified to obtain second-order nonlinear ordinary differential equations. The resulting differential equations are solved using differential transform method to obtain approximate solutions for the momentum and energy equations. The impacts of pertinent parameters, such as heat source/sink ($\delta$), Prandtl number ($\mathit{Pr}$), viscous heating ($\lambda$), suction/injection (S), and Strouhal number ($\mathit{St}$), on the velocity and temperature distributions in the periodic regime are illustrated using graphs and discussed. From the computational results, it is observed that an increase in the values of heat source/sink parameter ($\delta$) in the presence of viscous dissipation has significant influence on the flow and heat transfer. This study provides useful information in handling and processing the extraction of crude-oil-based slurries.