Multiple solutions for MHD transient flow of Williamson nanofluids with convective heat transport

Enhancing radiative efficiency in MHD micropumps using plasma-infused hybrid bioconvective nanofluids for advanced radiative oncology at tertiary level

This research paper investigates the optimization of radiation performance of a plasma-based bioconvective nanofluid integrated Magneto-hydrodynamic (MHD) micropump for radiative oncology. It addresses a literature gap by analysing the radiative impact of blood-based hybrid nanofluids in MHD micropumps. Three blood-based bio-convective radiating hybrid nanofluids-blood-Pt, blood-Au and blood-MWCNT are studied to understand their radiation behaviour in MHD pump while being employed as transportation medium. The investigation employs two non-dimensional parameters, namely Rd (Radiation number) and Ha (Hartmann number), to examine the fluid dynamics, magnetic characteristics, and electrical properties of the MHD micropump. The temperature gradient, velocity distribution, and pressure drop along the flow channel are examined within the specified range of Rd and Ha. Magnetic flux density (MFD) and electric flux intensity (EFI) are evaluated to understand nanoparticle behaviour during drug delivery and blood transportation. Findings highlight that MWCNT and Pt are the most efficient bioconvective nanoparticles for plasma transportation under high radiative conditions. MWCNT-based blood flow exhibits desirable characteristics, including sufficient intake pressure of 4.5 kPa and minimal relative pressure drop of 34%. Coherence between radiation flux and electromagnetic flux reduces pumping power and ensures uniform heat dissipation for improved drug delivery. Au nanoparticles provide moderate magnetic flux density with least fluctuation within the range of Ha and Rd number (2.57 T to 4.39 T), even in highly radiative environments (such as-Rd = 4, Rd = 5), making them suitable for applications like embedded chemotherapy or cell treatment. Au nanoparticles maintain moderate electrical flux intensity with a minimal drop of 16nA, particularly at higher radiative environments influenced by the Radiation number (Rd = 4 to Rd = 5) while Ha values from Ha = 2 to Ha = 4. Conclusively, it has been identified that MWCNT and Au are superior nanofluids for advanced radiative oncological treatments. These nanofluids have the potential to enhance plasma transportation, thermal regulation, and aetilogical disease management. The present study provides significant findings on enhancing the radiation performance in MHD micropumps through utilization of blood-based hybrid nanofluids, thereby offering potential advantages to the domain of biomedical engineering.

Williamson magneto nanofluid flow over partially slip and convective cylinder with thermal radiation and variable conductivity

This article is concerned with the study of MHD non-Newtonian nanofluid flow over a stretching/shrinking cylinder along with thermal radiation effects. Two-component slip mechanism models, namely Brownian motion and thermophoresis of nanofluid for the mass and energy transportation, developed by Buongiorno, are used. Convective heat transfer and nonuniform magnetic field are retained for the expanding/contracting cylinder. Variable thermal conductivity and heat generation effects along with slip boundary conditions are utilized over the cylinder surface. By utilizing the similarity transformation, these governing partial differential equations are converted into nonlinear ordinary differential equations (ODEs). To obtain numerical results, these ODE’S are solved by the shooting method using MATLAB software. The impact of different parameters like variable thermal conductivity, radiation parameter, magnetic parameter, Prandtl number, Brownian motion parameter, the magnetic parameter, Weissenberg number, the viscosity ratio parameter and mass transfer parameter, on the velocity, temperature and concentration is discussed graphically. Further, the Sherwood number, Nusselt number, the skin friction coefficient are also discussed through figures. It is noted through analysis that the speed of the nanofluid reduces for the higher Weissenberg number and expanding cylinder. For the contracting cylinder, i.e., for the negative unsteadiness parameter, the velocity increases.

Entropy Generation in Magneto-Casson Nanofluid Flow Along an Inclined Stretching Sheet Under Porous Medium with Activation Energy and Variable Heat Source/Sink

The current paper deals with the study of magneto-convective and chemically reactive Casson nanofluid flow along an inclined permeable stretching surface embedded in a fluid-saturated uniform porous medium. As a novelty of the work, entropy generation analysis in the presence of multiple slips at the surface and a nonuniform heat source/sink is carried out. Moreover, viscous dissipation, Arrhenius activation energy, Joule dissipation and thermal radiation are included in the investigation. To the best of authors’ knowledge, no such study on Casson nanofluid is reported yet in the literature. Dimensionless similarity transformations have been introduced to convert the regulating model PDEs into ODEs in dimensionless form. As the model equations are highly nonlinear in nature, shooting technique based on the Runge-Kutta Cash-Karp method is used to solve those equations numerically. The updated values of the initial guesses are computed with the help of secant iteration. Profiles for fluid velocity, temperature, nanoparticle concentration and entropy generation have been drawn to explain the impacts of several important parameters on momentum, thermal and mass fields. However, the surface drag force, heat and mass transport rates at the solid wall are illustrated using numerical data displayed in tabular form. Also, a linear regression model is derived for the local Nusselt number and the related physical parameters. Moreover, a comparison table is presented to confirm the correctness of the obtained results. A fantastic correlation of the present results with the existing results is reported. Graphical results reveal that for the rising values of the angle of inclination parameter and magnetic parameter velocity profiles are declined, but for the growing values of Eckert number and thermal radiation parameter temperature profiles are enhanced.

Heat Transport Phenomena for the Darcy–Forchheimer Flow of Casson Fluid over Stretching Sheets with Electro-Osmosis Forces and Newtonian Heating

In this study, an investigation has been carried out to analyze the impact of electro-osmotic effects on the Darcy–Forchheimer flow of Casson nanofluid past a stretching sheet. The energy equation was modelled with the inclusion of electro-osmotic effects with viscous and Joule dissipations. The governing system of partial differential equations were transformed by using the suitable similarity transformations to a system of ordinary differential equations and then numerically solved by using the Runge–Kutta–Fehlberg method with a shooting scheme. The effects of various parameters of interest on dimensionless velocity and temperature distributions, as well as skin friction and heat transfer coefficient, have been adequately delineated via graphs and tables. A comparison with previous published results was performed, and good agreement was found. The results suggested that the electric and Forchheimer parameters have the tendency to enhance the fluid velocity as well as momentum boundary layer thickness. Enhancements in temperature distribution were observed for growing values of Eckert number. It was also observed that higher values of electric field parameter diminished the wall shear stress and local Nusselt number.

MHD Williamson Nanofluid Flow over a Slender Elastic Sheet of Irregular Thickness in the Presence of Bioconvection

Bioconvection phenomena for MHD Williamson nanofluid flow over an extending sheet of irregular thickness are investigated theoretically, and non-uniform viscosity and thermal conductivity depending on temperature are taken into account. The magnetic field of uniform strength creates a magnetohydrodynamics effect. The basic formulation of the model developed in partial differential equations which are later transmuted into ordinary differential equations by employing similarity variables. To elucidate the influences of controlling parameters on dependent quantities of physical significance, a computational procedure based on the Runge–Kutta method along shooting technique is coded in MATLAB platform. This is a widely used procedure for the solution of such problems because it is efficient with fifth-order accuracy and cost-effectiveness. The enumeration of the results reveals that Williamson fluid parameter λ, variable viscosity parameter Λμ and wall thickness parameter ς impart reciprocally decreasing effect on fluid velocity whereas these parameters directly enhance the fluid temperature. The fluid temperature is also improved with Brownian motion parameter Nb and thermophoresis parameter Nt. The boosted value of Brownian motion Nb and Lewis number Le reduce the concentration of nanoparticles. The higher inputs of Peclet number Pe and bioconvection Lewis number Lb decline the bioconvection distribution. The velocity of non-Newtonian (Williamson nanofluid) is less than the viscous nanofluid but temperature behaves oppositely.

Mathematical modeling and analysis of SWCNT-Water and MWCNT-Water flow over a stretchable sheet

In this article we focused on the mixed convection flow of SWCNT-Water and MWCNT-Water over a stretchable permeable sheet. The nanofluid occupied porous medium. Darcy's law is used to characterize porous medium. The impact of viscous dissipation is considered. Transformation procedure is adopted to transform the governing PDE's system into dimensionless form. In order to solve the dimensionless PDE's system we used numerical method known as Finite difference method. Effects of flow variables i.e porosity parameter, suction parameter, Grashof number and Reynolds number on velocity, skin friction, temperature and Nusselt number are described graphically. The obtained results shows that velocity is dominant in SWCNT-Water over MWCNT-Water. Temperature is dominant in MWCNT-Water over SWCNT-Water.