Motile Density Research Articles

The role of radiation and bioconvection as an external agent to control the temperature and motion of fluid over the radially spinning circular surface: A theoretical analysis via Chebyshev spectral approach

The usage of nanoparticles is effectively increased in industries because of their high thermal performance. Moreover, the bioconvection phenomenon in nanomaterials leads to innovative biotechnology applications, such as biofuels, biosensors, the petroleum industry, etc. Because of the nanoparticle's exceptional performance and bioconvection phenomenon, the magnetohydrodynamics bioconvection Reiner–Rivlin nanofluid flow is considered over the rotatory stretchable disk contains the motile gyrotactic microorganisms. The heat and mass transport phenomenon with thermal radiation and activation energy is also investigated under convective‐Nield's boundary conditions. The governing partial differential equations (PDEs) are transmuted with specific similarity transformation into ordinary differential equations (ODEs). The obtained ODEs are solved numerically through the assistance of the Chebyshev spectral collocation method. The effects of the flow parameters on the boundary layer profiles are reported graphically. The graphical illustration elucidates that the dimensionless parameters have significantly affected the nondimensional boundary layer profiles. The fluid velocity, temperature, concentration of nanoparticles, and motile density of microorganisms are effectively controlled through the proper alteration of the pertinent parameters. The thermophoresis parameter decreases the heat and mass transport rates, whereas the Brownian motion parameter helps to increase them. Finally, the current research can successfully fill a gap in the existing literature.

Numerical framework for unsteady bioconvection flow of third-grade nanofluid over a porous Riga surface with convective Nield approach

The ultra-high significances of thermal radiation, magnetic field and activation energy in thermal enhancement processes allow significant applications in chemical and mechanical engineering, modern technology and various thermal engineering eras. The improvement in energy resources and production became one of the major challenges for researchers and scientists for sustained development in industrial growths. Beside this, the bioconvection assessment in nanomaterials conveys prestigious applications in biotechnology like bio-sensors, enzymes, petroleum industry, bio-fuels and many more. In view of such renewable applications, present exploration discloses unsteady two-dimensional flow of third-grade nanomaterial accommodating gyrotactic microorganisms induced by unsteady stretched Riga sheet in porous medium. The formulated flow problem is further scrutinized by utilizing the chemical reaction, activation energy, thermal radiation and magnetic aspects. The convective Nield constraints are further subjected in the current investigation. Apposite transformations are used to condense the nonlinear developed problem into dimensionless ordinary form. The numerical solution of such similar flow problem is presented via shooting technique. The detailed graphical illustrations of the dimensionless temperature, nanoparticles concentration, velocity and motile microorganisms for physical significance of diverse relevant parameters are deliberated. Furthermore, numerical data of local Sherwood, Nusselt and motile density numbers is designated in tabular form. Study accentuated that velocity increases for higher modified Hartmann and material constants, while the effects of buoyancy ratio and bioconvected Rayleigh numbers are rather opposite. The temperature, microorganism and concentration distributions were enhanced for unsteady parameter. It is also acknowledged that the concentration distribution is enhanced for activating the energy number. Moreover, the microorganism distribution enhances for concentration difference and magneto-porous constants, while bioconvected Lewis and Peclet numbers show conflicting trend.

Exploring the magnetohydrodynamic stretched flow of Williamson Maxwell nanofluid through porous matrix over a permeated sheet with bioconvection and activation energy

The evolution of compact density heat gadgets demands effective thermal transportation. The notion of nanofluid plays active role for this requirements. A comparative account for Maxwell nanofluids and Williamson nanofluid is analyzed. The bioconvection of self motive microorganisms, non Fourier heat flux and activation energy are new aspects of this study. This article elaborates the effects of viscous dissipation, Cattaneo–Christov diffusion for Maxwell and Williamson nanofluid transportation that occurs due to porous stretching sheet. The higher order non-linear partial differential equations are solved by using similarity transformations and a new set of ordinary differential equations is formed. For numerical purpose, Runge–Kutta method with shooting technique is applied. Matlab plateform is used for computational procedure. The graphs for various profiles .i.e. velocity, temperature, concentration and concentration of motile micro-organisms are revealed for specific non-dimensional parameters. It is observed that enhancing the magnetic parameter M, the velocity of fluid decreases but opposite behavior happens for temperature, concentration and motile density profile. Also the motile density profile decrease down for Pe and Lb. The skin friction coefficient is enhanced for both the Williamson and Maxwell fluid.

Bioconvection Mangnetohydrodynamic Tangent Hyperbolic Nanofluid Flow with Quartic Chemical Reaction Past a Paraboloid Surface

In this numerical study, the effect of quartic autocatalysis type of chemical reaction, buoyancy force and thermal radiation phenomenon and magnetic effect on tangent hyperbolic nanofluid past an upper horizontal surface of a paraboloid has been studied. By considering the Buongiorno model approach, a diffusion of unequal coefficients in the presence of gyrotactic microorganism is discussed. Implementation of microorganism's idea is used to stabilize the nanoparticles through bioconvection. The modeled PDEs of the problems are converted into nonlinear ODEs with the assistant of the similarity transformations. To tackle nonlinear ODEs, MATLAB package bvp4c is used. In addition, a hallmark of the Matlab code with the reported results in the literature is achieved by benchmarking. The variations in motion, concentration, temperature, and motile density due to sundry parameters have been analyzed in-depth via graphs. Our analysis shows that the density profile of motile of microorganism is hiked with an increment in the bioconvection Rayleigh number but decreases for higher thermal Grashof number.

Darcy-Forchheimer Flow of Magnetized Bioconvective Williamson Nanofluid with Variable Thermal Conductivity

In this article modeling and theoretical analysis of magnetized Williamson nanomaterial flow by permeable surface of cylinder is studied. The idea of self-propelled gyrotactic microorganisms is implemented to stabilize the suspended nanoparticles in Williamson liquid. Darcy-Forchheimer together with porosity effects are accounted in the flow. Energy relation is modeled in view of thermal radiation, variable thermal conductivity and Joule heating. Activation energy linked with chemical reaction is executed at the surface. Furthermore, Brownian dispersion and thermophoresis effects are also considered. Flow governing dimensional model is acquired using boundary layer suppositions. Suitable transformations are used to alter the system of PDE’s into non-dimensional. NDSolve code in Mathematica package is utilized to solve the model. Impacts of various flow regulating variables on velocity, temperature, mass concentration and motile density are investigated by plotting. Coefficient of skin friction, Sherwood number, motile density number and heat transfer rate are tabulated and analyzed. It is observed that velocity field decays while temperature field enhances versus rising dimensionless magnetic parameter. Moreover, due to magnetic field more Lorentz force is applied to the flow as a result surface drag force enhances while heat transfer rate decays.

Isothermal autocatalysis of homogeneous–heterogeneous chemical reaction in the nanofluid flowing in a diverging channel in the presence of bioconvection

The nonlinear differential equations play a prominent role in the mathematical description of many phenomena that occur in our world. A similar set of equations appear in this paper that govern the homogeneous and heterogeneous chemical reactions in the nanofluid flowing between two non-parallel walls. Since the concentration of the homogeneous species is substantially high, quartic autocatalysis is considered for the analysis. It is found to be more effective than the cubic autocatalysis. Further, to avoid the deposition of nanoparticles on the surface, self-propelled microorganisms called gyrotactic microorganisms are allowed to swim in the nanofluid. This movement of microorganisms constitutes a major phenomenon called bioconvection. The set of governing equations thus formed are made dimensionless and the resulting system of equations are solved by Differential Transformation Method (DTM) with the help of Padé approximant that reduces the power series into rational function. This transformation helps in achieving a better convergence rate. The fluid flow analysis is interpreted through graphs and tables where it is observed that the heat source enhances the temperature of the nanofluid. Further, the homogeneous and heterogeneous chemical reaction parameters have significant impacts on the concentration of the reactants. Also, the outcomes indicated that the reaction profiles and motile density profiles increase with the increase in Schmidt number.

Flow Analysis of Hybridized Nanomaterial Liquid Flow in the Existence of Multiple Slips and Hall Current Effect over a Slendering Stretching Surface

Carbon nanotubes (CNTs) are favored materials in the manufacture of electrochemical devices because of their mechanical and chemical stability, good thermal and electrical conductivities, physiochemical consistency, and featherweight. With such intriguing carbon nanotubes properties in mind, the current research aims to investigate the flow of hybridized nano liquid containing MWCNTs (multi-wall carbon nanotubes) and SWCNTs (single-wall carbon nanotubes) across a slendering surface in the presence of a gyrotactic-microorganism. The temperature and solutal energy equation are modified with the impact of the modified Fourier and Fick’s law, binary chemical reaction, viscous dissipation, and joule heating. The slip conditions are imposed on the surface boundaries. The flow equations are converted into ODEs by applying similarity variables. The bvp4c approach is applied to tackle the coupled and extremely nonlinear boundary value problem. The outputs are compared with the PCM (Parametric continuation method) to ensure that the results are accurate. The influence of involved characteristics on energy distribution, velocity profiles, concentration, and microorganism field are presented graphically. It is noted that the stronger values of the wall thickness parameter and the Hartmann number produce a retardation effect; as a result, the fluid velocity declines for MWCNT and SWCNT hybrid nano liquid. Furthermore, the transport of the mass and heat rate improves with a higher amount of both the hybrid and simple nanofluids. The amount of local skin friction and the motile density of microorganisms are discussed and tabulated. Furthermore, the findings are validated by comparing them to the published literature, which is a notable feature of the present results. In this aspect, venerable stability has been accomplished.

Investigation of mixed convection magnetized Casson nanomaterial flow with activation energy and gyrotactic microorganisms

Present article addresses mixed convection magnetohydrodynamic Casson nanomaterial flow by stretchable cylinder. The effects of thermal, solutal and motile density stratifications at the boundary of the surface are accounted. Flow governing expressions are acquired considering aspects of permeability, thermal radiation, chemical reaction, viscous dissipation and activation energy. The obtained flow model is made dimensionless through transformations and then tackled by NDsolve code in Mathematica. Physical impacts of sundry variables on nanomaterial velocity, temperature distribution, volume fraction of microorganisms and mass concentration is investigated through plots. Furthermore, quantities of engineering interest like surface drag force, heat transfer rate, density number and Sherwood number are computed and analyzed. We observed that fluid velocity diminishes for higher curvature variable, Casson fluid material variable, Hartmann number and permeability parameter. Fluid temperature has a direct relation with Eckert number, thermophoresis variable, Brownian dispersal parameter, Prandtl number and Hartmann number. Volume fraction of gyrotactic microorganisms is decreasing function of bioconvection Lewis number, stratification parameter and bioconvection Peclet number. Detailed observations are itemized at the end.

Numerical experiment of Reiner–Philippoff nanofluid flow subject to the higher-order slip features, activation energy, and bioconvection

The thermal mechanism of nanofluids due to advanced features is the most interesting research area owing to the applications in heat transmit devices, cooling procedure, energy production, etc. The nanofluids with motile microorganisms signify their importance in bio-medical engineering and biotechnology. This research communicates the accessed dynamic feature of Reiner–Philippoff nanofluid with applications of the bioconvection phenomenon. The magnetic force impact and activation energy features are also intended to perform the radiative analysis of Reiner–Philippoff nanomaterial. The slip features higher-order relations are incorporated to analyze the flow. The modifications in the energy equation are suggested by using thermal radiation with nonlinear relationship. The flow equations, which in turn to non-dimensionless form, are numerically tackled with a shooting scheme. A comprehensive thermal analysis for the endorsed parameters is presented. The numerical data is achieved to examine the fluctuation in heat, mass, and motile density function. The simulated results show that the velocity profile improves with Philippoff fluid parameter while a declining change is noticed for the slip parameter. With increase of Philippoff fluid parameter, both temperature and concentration profile declined. The consideration of higher order slip is more effective for increasing the temperature, concentration and microorganisms’ profiles.

Analysis of Heat and Mass Transfer Features of Hybrid Casson Nanofluid Flow with the Magnetic Dipole Past a Stretched Cylinder

The main purpose of this research is to scrutinize the heat and mass transfer in the Casson hybrid nanofluid flow over an extending cylinder in the presence of a magnetic dipole and double stratification. The nanofluid contained chemically reactive hybrid nanoparticles (Ag, MgO) in the conventional fluids (water). The effects of viscous dissipation, radiation, and concentration stratification were taken into consideration. In the presence of gyrotactic microorganisms and the Non-Ficks Model, the flow was induced. Incorporating microorganisms into a hybrid nanofluid flow is thought to help stabilize the dispersed nanoparticles. For viscosity and thermal conductivity, experimental relations with related dependence on nanoparticle concentration were used. To acquire the nonlinear model from the boundary layer set of equations, suitable similarity transformations were employed. The built-in function bvp4c of Matlab software was utilized to solve the transformed equation numerically. The graphical results were obtained for temperature, velocity, concentration, and microorganism distribution for various parameters. The numerical amounts of drag friction, heat transport rate, and motile density number for different parameters are presented through tables. It is seen that the fluid velocity is augmented by the increase of the curvature parameter, while a decrease occurs in the fluid velocity with an increase in the magnetic and slips parameters. The comparison of the present study with previously available studies is discussed, which shows a good agreement with published results.

Aspects on unsteady for MHD flow of Cross nanofluid having gyrotactic motile microorganism due to convectively heated sheet

The motive of the current analysis is to examine the role of gyrotactic microorganisms to reveal their behaviour in heat and mass transfer in time-dependent MHD flow of Cross fluid accounted through nanoparticles. Non-linear thermal radiative, viscous dissipation, Soret and Dufour effect are also scrutinised with constraining conditions. By applying the suitable alteration the system of PDEs is transmuted into ODEs. The transmuted ODE’s are utilised through RK-4 along with shooting techniques. Moreover, the impact of various emerging variables on the velocity, temperature, concentration and density of motile microorganisms are deliberated numerical and graphical. The outcomes are presented through plots and tables. Further, the outcomes illustrated that enhancements in the value of Weissenberg number We result in a reduction in motile density microorganism while the opposite effect is examined in the velocity slip effect. In addition, an intensifying microorganism profile is observed with velocity slip effect, Peclet number. Comparisons have been prepared with previously published literature and found an outstanding agreement.

Numerical study of axisymmetric magneto-gyrotactic bioconvection in non-Fourier tangent hyperbolic nano-functional reactive coating flow of a cylindrical body in porous media

Modern functional nanomaterials coating processes feature an increasing range of intelligent properties including rheology, biological (bio-inspired) modifications, elaborate thermophysical behaviour and complex chemical reactions which are needed for the precise synthesis of bespoke designs. Such manufacturing flow processes are extremely complex and involve both heat and multiple mass transfer (species diffusion) phenomena. Intelligent nano-coatings are particularly attractive since they exploit magnetic nanoparticles which can be manipulated by external magnetic fields. Recently, Boeing Aerospace have explored the use of micro-organisms for intelligent aircraft coatings. Mathematical models provide an excellent analysis for elucidating the response characteristics of such coating dynamics processes. With this motivation, the present analysis is indented to develop a new mathematical model to examine the axisymmetric, magnetohydrodynamic, chemically reactive, gyrotactic bioconvection flow of a tangent hyperbolic nanofluid past a cylinder saturated with Darcy porous medium, as a model of smart-coating enrobing flow. The influence of Cattaneo–Christov heat flux (non-Fourier thermal relaxation parameter), thermophoresis and Brownian motion are taken into consideration. The steady-state, boundary layer, partial differential conservation equations are rendered dimensionless via appropriate transformations, and the subsequent nonlinear, coupled, system of governing equations is numerically solved by employing implicit Keller box method. The impact of various factors such as Hartmann magnetic number, Weissenberg viscoelastic parameter, Prandtl number, non-Fourier thermal relaxation parameter, thermophoresis, Brownian motion, micro-organisms concentration difference variable, chemical reaction, bioconvection Peclet number, Schmidt number and bio-convection Schmidt number on the flow, heat transfer, mass transfer, motile density, local friction factor, local heat transfer rate, local mass transfer rate and local microorganism density number wall gradient is visualized graphically. Validation with earlier studies is included. Further validation with a finite element method (FEM) code (SMART-FEM) is presented. Results reveal that the heat transfer upsurges for amplifying the Weissenberg number and Hartmann magnetic number. Microorganism concentration distribution of the non-Newtonian nanofluid coating diminishes for amplifying the bioconvection Schmidt number and Peclet number. Magnifying the power law index parameter reduces the momentum boundary layer thickness of tangent hyperbolic nanofluid, while there is an acceleration in the fluid flow near the surface of the cylinder. Local Sherwood number rises with higher values of homogenous destructive chemical reaction parameter. The computations provide a solid benchmark for further CFD modelling.

Stratified heat transfer of magneto-tangent hyperbolic bio-nanofluid flow with gyrotactic microorganisms: Keller-Box solution technique

Abstract The purpose of the present investigation is to examine the heat, mass and microorganism concentration transfer rates in the magnetohydrodynamics (MHD) stratified boundary layer flow of tangent hyperbolic nanofluid past a linearly, uniform stretching surface comprising gyrotactic microorganisms as well as nanoparticles. The governing PDEs with relevant end point conditions are molded into a non-dimensional ordinary differential equation (ODE) form by means of the similarity transformation. The numerical solution of dimensionless problem is acquired within the frame of robust Keller-Box technique. The velocity, temperature, mass and motile microorganism density are investigated graphically within the context of different significant parameters. Numerical results have been inspected via plots and table (namely as the local Nusselt number, the local wall mass flux and the local microorganisms wall flux). This article proves that the energy, concentration and motile microorganism density reduce with increase in thermal, solutal and motile density stratification parameters. The asserted outcomes are beneficial to enhance the cooling and heating processes, energy generation, thermal machines, solar energy systems, industrial processes etc.

Numerical Simulations of Bio-Convection in the Stream-Wise and Cross-Flow Directions Comprising Nanofluid Conveying Motile Microorganism: Analysis of Multiple Solutions

This work tackles the phenomenon of motile microorganisms and nanoliquid flow in the esteem of cross-flow (CF) and stream-wise (SW) direction. The analysis exposed to viscous dissipation, Brownian motion, thermal radiation, magnetic function, and thermophoresis impacts is encountered. The mathematical model consists of the partial differential equations (PDEs) switched into nonlinear ordinary differential equations (ODEs) through proper transformations of new variables. The multiple outcomes of the flow problem are achieved through the Lobatto IIIA formula. The features of controlling constraints are sketched for the motile organism, temperature, velocities (CF and SW), and concentration fields. Also, the Sherwood and the Nusselt numbers along with motile density and friction factor are sketched. One imperative numerical outcome of this research is the existence of dual numerical solutions for the nanofluid flow. The upshots indicate that the profiles of microorganisms decelerate due to bio-convection Schmidt and Péclet numbers. The magnetic function decelerates the velocity in the directions of SW and CF in the branch of the first solution and upsurges in the branch of the second solution. The concentration profile uplifts due to [Formula: see text] in both solutions while the opposite behavior is observed for different values of [Formula: see text] in both solutions. The temperature uplifts due to magnetic and radiation effects in both solutions.

Bioconvection Reiner-Rivlin Nanofluid Flow between Rotating Circular Plates with Induced Magnetic Effects, Activation Energy and Squeezing Phenomena

This article deals with the unsteady flow in rotating circular plates located at a finite distance filled with Reiner-Rivlin nanofluid. The Reiner-Rivlin nanofluid is electrically conducting and incompressible. Furthermore, the nanofluid also accommodates motile gyrotactic microorganisms under the effect of activation energy and thermal radiation. The mathematical formulation is performed by employing the transformation variables. The finalized formulated equations are solved using a semi-numerical technique entitled Differential Transformation Method (DTM). Padé approximation is also used with DTM to present the solution of nonlinear coupled ordinary differential equations. Padé approximation helps to improve the accuracy and convergence of the obtained results. The impact of several physical parameters is discussed and gives analysis on velocity (axial and tangential), magnetic, temperature, concentration field, and motile gyrotactic microorganism functions. The impact of torque on the lower and upper plates are deliberated and presented through the tabular method. Furthermore, numerical values of Nusselt number, motile density number, and Sherwood number are given through tabular forms. It is worth mentioning here that the DTM-Padé is found to be a stable and accurate method. From a practical point of view, these flows can model cases arising in geophysics, oceanography, and in many industrial applications like turbomachinery.

LOW PERCENTAGE MOTILITY WHEN SPERM CONCENTRATION IS NORMAL DOES NOT APPEAR TO BE A CAUSE OF UNEXPLAINED FAILURE TO HAVE A LIVE DELIVERY DESPITE IN VITRO FERTILIZATION (IVF)

Some data suggest that sperm with very low motile density can lead to a trend for a lower chance of a live delivery following in vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI) even despite the transfer of embryos with apparent normal morphology. The purpose of the present study was to see if low % motility in the presence of normal sperm concentration can also be a subtle cause of unexplained infertility. Couples were identified who were sharing donor oocytes when both male partners had normal concentrations of their sperm (≥20x106/mL) but where one had motility <30% and the other ≥50%. Subsequent fertilization rates, embryo quality, as evidence by number of blastomeres on day 3 transfer, and pregnancy rates were determined. ICSI was used or not according to the discretion of the physician. Tabled 1Pregnancy rates based on % motility for shared oocyte cycles when sperm concentration ≥20 mill/mLMotility<30%≥50%# cycles3737% fertilized70.5%70.1%% 6-8 cell day 360.6%70.7%% clinical pregnancy/transfer58.3%68.0%% miscarriage/clinical pregnancy live0.0%35.3%% delivered58.3%44.0%% implantation31.3%40.0% Open table in a new tab There were no statistical differences or trends that would suggest that low % motile sperm, despite normal sperm concentration, leads to embryos with a lower chance to achieve a live delivery. With no trends seen at all, the study will not be continued. Based on other studies, there is a suggestion that sperm from men with very low motile density, used for IVF-ET, the embryos formed, though appearing to be morphologically normal, may be the cause of lower live delivered pregnancy rates. This raised the question as to the possibility that sperm with very low MD may be more likely to have chromosome defects. That data was also based on similar evaluation of matched pairs sharing one pool of oocytes, thus ruling out an oocyte factor. It does not seem that low percentage of sperm motility is a subtle cause of unexplained infertility when sperm concentration was normal based on this pilot study.

Magnetized and non-magnetized Casson fluid flow with gyrotactic microorganisms over a stratified stretching cylinder

This study presents the magnetized and non-magnetized Casson fluid flow with gyrotactic microorganisms over a stratified stretching cylinder. The mathematical modeling is presented in the form of partial differential equations and then transformed into ordinary differential equations (ODEs) utilizing suitable similarity transformations. The analytical solution of the transformed ODEs is presented with the help of homotopy analysis method (HAM). The convergence analysis of HAM is also presented by mean of figure. The present analysis consists of five phases. In the first four phases, we have compared our work with previously published investigations while phase five is consists of our new results. The influences of dimensionless factors like a magnetic parameter, thermal radiation, curvature parameter, Prandtl number, Brownian motion parameter, Schmidt number, heat generation, chemical reaction parameter, thermophoresis parameter, Eckert number, and concentration difference parameter on physical quantities of interests and flow profiles are shown through tables and figures. It has been established that with the increasing Casson parameter (i.e. beta to infty), the streamlines become denser which results the increasing behavior in the fluid velocity while on the other hand, the fluid velocity reduces for the existence of Casson parameter (i.e. beta = 1.0). Also, the streamlines of stagnation point Casson fluid flow are highly wider for the case of magnetized fluid as equated to non-magnetized fluid. The higher values of bioconvection Lewis number, Peclet number, and microorganisms’ concentration difference parameter reduces the motile density function of microorganisms while an opposite behavior is depicted against density number.

Implication of Bio-convection and Cattaneo-Christov heat flux on Williamson Sutterby nanofluid transportation caused by a stretching surface with convective boundary

This theoretical and computational analysis reveals the thermal characteristics for the flow of Williamson Sutterby nanofluid through the Darcy–Forchheimer sponge medium over an extending surface. The Cattaneo-Christov heat flux, radiation heat flux, and convective boundary are taken into account. Moreover the impacts of bio-convection of self-propelled micro-organisms and electromagnetic fields are considered. The amalgamation of Sutterby–Williamson with slight homogeneous diffusion of nano-particles and micro-organism exposes the novelty of this work. The principal objective pertains to avoid the possible settling of nano-entities to given effective heat transportation. The physical problem is formulated in the form of partial differential equations which are then altered to a system of ordinary differential equations. The influences of emerged parameters on the physical quantities of interest are evaluated by utilizing the Runge–Kutta method. The parameters of Sutterby fluid, inertia friction and porosity decelerate the flow but the parameters of electric field and mixed convection are directly responsible to promote the velocity of fluids. It is noted that fluid accelerates for Williamson model λ≠0. The parameter of the electric field, Brownian motion, radiations, thermophoresis, and Eckert number raises the temperature of the fluid. The heat transfer rate at the surface recedes in magnitude for larger b (Cattaneo-Christov diffusion). The motile density number increases with the upsurge values of Lb, Pe and Ω. Two sets of graphical outputs are presented for Williamson fluid parameter λ(λ=0,λ=0.5).

Bio-convective couple stress nanofluid behavior analysis with temperature-dependent viscosity and higher order slip encountered by a moving surface

In nanotechnology, the nanofluids are decomposition of base materials and nanoparticles where the nanoparticles are immersed in base liquid. The utilization of such nanoparticles into base liquids can significantly enhance the thermal features of resulting materials which involve applications in various industrial and technological processes. While studying the rheological features of non-Newtonian fluids, the constant viscosity assumptions are followed in many investigations. However, by considering the viscosity as a temperature-dependent is quite useful to improve the heating processes along with nanoparticles. Keeping such motivations in mind, this investigation reports the temperature-dependent viscosity and variable heat-dependent conductivity in bioconvection flow of couple stress nanoparticles encountered by a moving surface. The famous Reynolds exponential viscosity model is used to deploy the relations for temperature-dependent viscosity. Moreover, the activation energy and higher order slip (Wu’s slip) are also elaborated to make this investigation more novel and unique. The emerging flow equations for governing flow problem are formulated which are altered into non-dimensional forms. The numerical simulations with applications of Runge–Kutta fourth–order algorithm are focused to obtain the desired solution. Before analyzing the significant physical features of various parameters, the confirmation of solution is done by comparing the results with already reported investigations as limiting cases. The results are graphically elaborated with relevant physical consequences. Various plots for velocity, temperature, concentration, wall shear stress, local Nusselt number, local Sherwood number and motile density numbers are prepared.

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.