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Suction-Enhanced Nanofluid Flow with Vibration Thermophoresis and Brownian Motion Considerations: A Peristaltic Study
(2026-01-01)
Govindan, Vediyappan
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Lakshmi, R.
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Vijayakumar, P.
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Pimpunchat, Busayamas
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Althobaiti, Maha M.
Purpose: In recent years, nanofluids have been widely used in energy technologies and have already shown significant promise in the thermal amplification of numerous manufacturing industries. Due to its numerous applications in the operation of mineral oils, water, solar energy, and microelectronics, the study of nanofluid is becoming a significant area of research. For this reason, the present framework looks into how suction and injection affect the properties of the nanofluid flow. This article has addressed the role of the slip effect, another significant physical component in the flow analysis. Methods: The mathematical analysis in this paper was conducted using low Reynolds number and long wavelength approximations. Analytical equations for temperature profile, velocity, pressure rate nanoparticles, and stream function are developed. Pressure gradient, velocity, frictional force, and other physical properties are combined to generate a graphic representation. Results: Brownian motion features and thermophoresis serve as examples of the extraordinary properties of nanofluid. In many operating systems with higher temperature gradients, thermophoresis is relevant to mass transport processes. The influence of thermophoresis and Brownian motion factors on flow characteristics was demonstrated using graphs. The profile of temperature rises with an increase in the thermophoresis parameter. The volume fraction of nanoparticle profiles decreases with an increase in thermophoresis factors. Conclusion: Numerous industrial and biological applications, blood pumps in heart and lung machines, including the movement of hygienic fluids, the transfer of caustic fluids where it is forbidden for the fluid to come into touch with equipment parts, call for this type of study. Medical procedures like oxygenation and hemodialysis can benefit from this research as well.
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Modeling water quality assessment-based MHD flow with Forchheimer and chemical reaction effects over a stretching melting surface via RSM
(2026-01-01)
Govindan, Vediyappan
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Pimpunchat, Busayamas
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Shaw R, Shaik Mohiddin
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Byeon, Haewon
The study of magnetohydrodynamic (MHD) boundary layer flow over melting surfaces embedded in Darcy–Forchheimer porous media is essential for improving thermal management in industrial processes such as metal casting, polymer extrusion, and geothermal heat extraction. This research numerically investigates the combined effects of chemical reaction, thermal radiation, viscous dissipation, and Forchheimer inertial resistance on the velocity, temperature, and concentration distributions within an electrically conducting fluid flowing over a moving, melting surface. Assuming an incompressible Newtonian fluid and employing similarity transformations, the governing equations are formulated based on the conservation of mass, momentum, energy, and species concentration. The resulting system of nonlinear ordinary differential equations (ODEs) is solved using a shooting method in conjunction with the fourth-order Runge–Kutta scheme. Overall, the proposed numerical model effectively captures the interplay of magnetic, thermal, and chemical effects, offering valuable insights for the design of efficient thermal systems involving melting processes and porous structures.
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Stability and Hopf Bifurcations Analysis in a Three-Phase Dengue Diffusion Model With Time Delay in Fractional Derivative and Laplace–Adomian Decomposition Numerical Approach
(2025-08-01)
Vijayalakshmi, G. M.
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Ariyanatchi, M.
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Govindan, Vediyappan
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Byeon, Haewon
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Pimpunchat, Busayamas
This study examines the complex dynamics of dengue transmission by incorporating time delay into a comprehensive model. The model is designed to capture several essential components, including steady-state events, immune waning, recuperation from infection, and partial shielding in human populations. To further refine our understanding, we introduce a fractional framework that provides a more precise perspective on the finer dynamics of the model. Through the framework of the stability theory of delayed differential equations, this study closely analyzes the stability of local and disease-free equilibria. As the fundamental reproducibility number ((Formula presented.)) exceeds unity, the experiment exhibits instability. This provides the basis for delay-parameterized Hopf bifurcation analysis. The stability conditions for local equilibrium are explained, and reliable numerical simulations confirm the mathematical framework and provide strong support for our conclusions. Additionally, the study uses fixed-point theory to verify that the model has a unique solution. In addressing the subtleties of fractional-order differential equations, we use the Laplace–Adomian decomposition method, assigning a unique fractional order ((Formula presented.)) to each segment. The resulting approximate solutions are visualized through graphical depictions, providing valuable insights into the influence of fractional parameters ((Formula presented.)) on the complex dynamics underlying dengue transmission. This research, with its holistic overview and innovative methodology, makes a significant contribution to our understanding of dengue dynamics. The implications of these findings extend to the area of public health strategies, improving our ability to plan interventions and reduce the impact of dengue on vulnerable populations.
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Brownian motion effects and thermophoresis on heat transmission mechanism of hybrid nano liquid flow over a stretched wedge surface
(2025-06-01)
Swami, Sharanayya
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Biradar, Suresh
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Tawade, Jagadish V.
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Govindan, Vediyappan
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Byeon, Haewon
The current study observes the impact of thermophoresis, Brownian motion, and magnetic fields on the flow and heat transfer properties of a hybrid nanofluid containing Al<inf>2</inf>O<inf>3</inf>, CuO, and ethylene glycol over a wedge-shaped surface undergoing horizontal stretching. The study addresses the critical need to enhance energy transfer and thermal management systems, which have significant technical and industrial applications. To model the problem, flow equations were transformed into ordinary differential equations using similarity transformations and solved numerically via the Runge-Kutta-Fehlberg method. The results reveal that the wedge angle and magnetic field strength are crucial factors influencing the flow and thermal behavior. Specifically, increasing the wedge angle enhances the Nusselt number but reduces the thermal and diffusion profiles. The suction and injection of the fluid significantly impact the local heat transfer rates and boundary layer thickness. Additionally, the Buongiorno slip parameter reduces the rate of energy transfer while amplifying thermal distributions. The thermophoresis parameter was found to influence both concentration and thermal boundary layers. A comparative analysis between Newtonian and non-Newtonian fluids showed that hybrid nanofluids improve mass and energy transfer rates in both cases, with enhanced effects observed in non-Newtonian fluids. The study's novelty lies in its comprehensive exploration of magneto-flow dynamics and hybrid nanofluid behavior in the context of wedge geometries and external magnetic fields. The findings extend previous research by offering quantitative insights into how key parameters like wedge angles, thermophoresis, and Brownian motion affect heat and mass transfer processes, providing a robust framework for optimizing hybrid nanofluid applications in engineering and industrial systems. The results align well with existing literature, validating the study's contributions to the field.
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Effects of mass transfer and MHD Casson nanofluid heat transfer on thermophoresis at stagnation point
(2025-05-01)
Seethamahalakshmi, V.
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Venkata Kalyani, U.
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Padma, A.
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Nagalakshmi, P. S.S.
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Ramana Reddy, G. V.
This study seeks to analyse the magnetohydrodynamic (MHD) flow of a nanofluid, focussing on heat and mass transfer in nano liquids over a stretchable surface near a stagnation point, while considering changeable thermal conductivity. The thermal behavior of the suspended nanoparticles is found to be significantly affected by Brownian motion. The influence of the chemical responses well as the continuous inner warmth source or washbasin are in addition taken into account. The governing equations are changed into a system of coupled ordinary differential equations utilising an appropriate similarity transformation. The computational software PYTHON is employed to address the boundary value problem (BVP) utilising the shooting method. The numerical results are supported by the online PYTHON software function bvp4c. The numerical results are derived by varying the values of the physical parameters associated with the flow problem. The results are presented in graphical and tabular formats. As the thermal energy of the liquid increases, the thermophoresis values trend upward, while the Nb values show a downward trajectory. Also, we found that the response rate encourages a reduction in the thermal boundary layer's thickness.
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Numerical simulation of unsteady MHD bio-convective flow with Cattaneo-Christov heat flux over a stretching surface
(2025-04-01)
Shalini, Chinnam A.A.E.
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Ganteda, Charankumar
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Reddy, G. V.Ramana
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Maheswari, B. Uma
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Kokila, G.
The study explores the properties of mass and heat transfer in a time-dependent, unsteady magnetohydrodynamic (MHD) flow over a permeable, radiative, and expanded surface, incorporating bio-convection, nanoparticle suspension, and gyrotactic bacteria dynamics. The model considers the effects of emission, speed slip, and bio-thermal convection in the fluid system. The Cattaneo-Christov heat flux model is employed to account for the finite speed of thermal diffusion, and the fourth-order Runge-Kutta method with the shooting technique is utilized for numerical solutions. Additionally, the study investigates the influence of mass suction, heat source, and aligned magnetic field on the boundary layer. The local concentration of mobile microorganisms decreases as the stretching parameter and bio-convection Schmidt both improve. The concentration φ(η) gets stronger, and when Sc values increase, it decreases. The concentration of microorganism h(η) is strengthened by increasing angle β, but it is diminished by increasing Pe,Sb and Sc, respectively.Even if the rate of temperature transmission (Nu) is maximal for positive values of A relative to negative values, the friction drags (C<inf>f</inf>) are more powerful for negative values of A than for positive values of A.
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Mechanism of thermal radiation, soret-dufour on ferromagnetic hybrid nanofluid through a permeable surface
(2025-04-01)
Krishnaveni, T. Radha
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Ramana Reddy, G. Venkata
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Anitha, J.
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Kumar, G. Charan
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Rajagopalan, N. R.
Mechanisms of thermal radiation, Soret-Dufour on Ferromagnetic hybrid nanofluid through a permeable surface has been considered in this paper. The higher thermal condition of the hybrid nanofluid was discussed alongside an induced magnetism. A partial differential equation (PDEs) has been used to describe the physical problem. The set of modeled PDEs was changed into ordinary differential equations and solved numerically using the spectral relaxation method (SRM). The outcome of the numerical simulations was presented graphically. The thermal radiation was discovered to greatly influence the thermal condition of the hybrid nanofluid. It was observed that the Soret term enhances the concentration layer while the Dufour term enhances the temperature layer. The outcome of this study was compared with previous work and found to be in good agreement.
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On Cattaneo-Chrystov heat flux model for nanofluid flow on Darcy–Forchheimer porous medium past unsteady stretching cylinder
(2025-03-01)
Sobhanapuram, Sreedhar
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Devi, S. V.V.Rama
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Ganteda, Charankumar
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Kottapalli, Rajyalakshmi
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Govindan, Vediyappan
In a Darcy-Forchheimer porous medium with variable thermal conductivity, this work describes the convective transport mechanisms of Williamson nanofluid and nanofluid flow via an unstable stretched cylindrical sheet. The governing boundary evaluates issue of the flow regime is formulated utilizing the conservation laws of mass, momentum, energy. A couple of nonlinear partial differential constitutions are used to express the flow. A suitable similarity transformation along with certain approaches are applied to convert the pair of partial differential constitutions into an initial value problem system. In this analysis, the Cattaneo-Chrystov model is introduced. After that, the shooting strategy and the Runge-Kutta fourth order are used to numerically solve the system of initial value problems. Analysis is done on the effects of several factors on the nanofluid's temperature, velocity, and concentration contours. such as the thermal conductivity parameter, the concentration and temperature Biot numbers, the unsteady parameter, and others. Conversely, larger values of the unstable parameter result in significant wall friction that hinders the nanofluid'smobility. Furthermore, under widely accepted assumptions, the numerical approach found here shows great agreement with several previous efforts. An uplifting in the unsteady factor causes the nanofluid's temperature and concentration boundary layers to enlarge. When the corresponding Biot numbers (thermal and concentration) grow, the two boundary layers of the nanofluid expand, initiating the convective mass and heat transfers from the wall to the system. The rates of mass and heat transfers increase and decrease in tandem with increases in the thermal conductivity parameter and thermal Biot number, respectively; however, the transfers exhibit the opposite behavior for higher concentration Biot number values.Compared with the existing research, the outcomes demonstrate excellent congruence.
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Numerical exploration of Hall and Dufour effects on rotating MHD natural convection near an infinite vertical plate with ramped boundary conditions using FDM and RSM using combined FDM and RSM approaches
(2025-03-01)
Mopuri, Obulesu
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Ganteda, Charankumar
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Palegari, Rudraravi Kumar
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Jaya Lalitha, G.
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Harikrishna, P.
This study investigates the effects of ramped parameters, diffusion thermo effects, radiation and heat absorption, Soret, and Hall effects on rotating MHD free convective flow under simultaneous ramped boundary conditions. The governing equations are transformed into dimensionless form and solved using an explicit finite difference method (FDM), with numerical results for velocity, temperature, concentration, viscous drag, heat, and mass transfer rates analyzed using MATLAB. Results show that increasing ramped parameters enhances momentum, heat, and mass transfer rates, with a novel observation of increased fluid velocity under stronger magnetic constraints. Additionally, the finite response method (FRM) is proposed to optimize parameter interactions, enabling efficient modeling and prediction of outcomes for variations beyond those tested in the FDM. This integration enhances understanding of sensitivities and optimal conditions in fluid behavior under simultaneous ramped constraints.
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Numerical study on thermal radiation and chemical reaction impacts on Prandtl nanofluid flow over a bilinear stretching sheet with heat generation and absorption: Response surface methodology
(2025-02-01)
Padmavathi, L.
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Kumar, S. Geethan
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Ganteda, Charankumar
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Varma, S. V.K.
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Gouthami, E.
The study focuses on the three-dimensional flow of a non-Newtonian Prandtl nanofluid with electrical conductivity, flowing over a bilinear expanding surface within a porous medium. These flows in porous medium are applied in water purification processes, petroleum industries and also chemical factories. The exploration examines various heat and mass transport phenomena, including the consequences of thermal radiation, thermophoresis, Brownian motion, substance response and heat source/sink. The governing partial differential equations are reformulated into a system of nonlinear ordinary differential equations through the application of appropriate similarity transformations. These equations are subsequently solved by using numerical methods bvp4c as well as shooting method. Furthermore, the arithmetical values for the friction factor and the temperature and accumulation constants are provided in tables. It is experiential that the Prandtl fluid constraint enhances the axial and transverse velocities, while the temperature sharing shows an inverse relationship. The temperature and concentration distributions have an opposite attitude with the influence of Brownian motion parameter.

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