Increase In Volume Fraction Of Nanoparticles Research Articles

Heat transfer augmentation of Jeffery–Hamel hybrid nanofluid in a stretching convergent/divergent channel through porous medium

<p>The primary objective of the present study was to investigate the enhancement of heat transfer in a Jeffery–Hamel hybrid nanofluid through a porous medium, within stretching/shrinking and convergent/divergent channels. The Darcy–Forchheimer (DF) law was employed to model the flow and thermal behavior of the nanofluid. The governing system of equations was derived using appropriate transformations. Numerical computations were performed using the NDSolve method in Mathematica-11. Results are presented through numerical data and graphical representations, illustrating the effects of various physical parameters on the flow profiles. Key findings indicate that increasing the inertia coefficient and nanoparticle volume fraction accelerates the velocity of the nanofluid in both divergent and convergent channels. Furthermore, higher porosity and inertia coefficients lead to increased drag forces exerted by the channel. Jeffery–Hamel hybrid nanofluids are significantly enhanced by increasing nanoparticle volume fraction, inertia coefficient, porosity, and the presence of radiation and heat source parameters, with a notably higher rate observed in the case of an expanding channel compared to a contracting one.</p>

Forced convection Heat transfer enhancement and entropy generation of non-Newtonian CNT–water nano-fluid in a channel with a wavy bottom wall

Numerical investigations have been conducted on the forced convection and entropy generation of a non-Newtonian Carbon Nanotube (CNT)-water nanofluid in a channel featuring a wavy bottom wall. The injected fluid is at a lower temperature than the horizontal walls. The governing equations are resolved using the finite volume method, which is founded on the SIMPLE algorithm. A diverse array of Reynolds numbers, corrugation numbers, power indices, wave amplitudes, and nanofluid volume fractions has been subjected to extensive numerical simulations. The influence of these characteristics on the local Nusselt numbers is analyzed. This study concludes that the incorporation of CNT nanoparticles and an increase in the number of corrugations can promote heat transfer in channels. The results indicate that heat transmission is markedly enhanced at low power-law indices. The local Nusselt number, indicative of heat transport, increases with the amplitude of undulations. Fluid velocity causes the local Nusselt number to rise when the Re number does. It was found that the heat transfer increases with decreasing power index due to the decrease in viscosity of the nanofluid and the local Nusselt number increases with increasing nanoparticle volume fraction. The results also showed that the entropy due to heat transfer and friction in corrugated channels is significantly affected by Reynolds number, power index, wave amplitude, corrugation number and nanoparticle volume fraction. By appropriate selection of these parameters, the heat transfer efficiency can be increased.

Advancement of nanoparticles in blood flow with non-linear radiation and optimisation of irreversibility within the microchannel using analysis of variance and Taguchi approach

Nanoparticles in blood flow play a pivotal role because of their extensive use in biomedicine, tissue engineering, and blood coagulation. Gold and Zinc nanoparticles have been proven to be stable and non-toxic to humans. Also, gold nanoparticles are biocompatible with less cytotoxicity, which makes them best suited for therapeutic drug delivery. Both gold and zinc nanoparticles in the blood are allowed to flow through an inclined microchannel, anticipating the couple stresses experienced by the fluid particles. The non-linear radiation and heat source components are contemplated in the study. The modelled equations are solved numerically with the aid of the finite difference technique. Analysis of variance and Taguchi optimization technique are applied to the entropy generated during the flow in the system. This method has proposed the optimal values for the parameters to achieve the least entropy. Outcomes have reported that as the effects of couple stress inverse parameter increase, the velocity of the fluid increase. Additionally, the flow profiles show an increase over time. The thermal field increases with the convection-radiation parameter, and declines with an increasing nanoparticle volume fraction. We observe an increase in irreversibility with enhanced radiation and the temperature difference parameter. The nanofluid phase's velocity and temperature are high in comparison to the hybrid nanofluid phase. The ANOVA-Taguchi method reveal that the couple stress inverse parameter has a 0.5 % impact, whereas the temperature gradient parameter has the highest impact on entropy generation, which is 56.14 %. Manipulation of the temperature gradient parameter is critical in regulating the irreversibility generated in the channel.

Thermal management optimization of natural convection in a triangular chamber: Role of heating positions and ternary hybrid nanofluid

In this paper, we used the multi-relaxation time lattice Boltzmann method to investigate natural convection in a triangular-shaped cavity filled with a tri-hybrid nanofluid. The cavity is partially heated by a chip of fixed size (l=L/2), the position of which varies on the left and bottom walls in order to find the optimal positions. The inclined side is maintained at a cool temperature, while the other parts are adiabatic. A detailed analysis is carried out on the impact of four essential parameters on the optimization of heat transfer: the Rayleigh number, ranging between Ra = 103 and Ra = 106; the partial heating position, showing the cavity in six different configurations; the fluid type, including pure water, nanofluid, hybrid nanofluid, and tri-hybrid nanofluid; and finally, the volume concentration of the nanoparticles for three values, ϕ = 0%, 3%, and 6%. Results are presented in the form of isotherms, streamlines, temperature and velocity profiles, and the mean Nusselt number values. As the results show, the position of the partial heater plays a crucial role, influencing natural convection heat transfer significantly in certain positions at all values of the Rayleigh number. The type of fluid has a remarkable impact on the amplification of natural convection at large values of the Rayleigh number, where the buoyancy force becomes strong. Notably, the use of tri-hybrid nanofluid shows a clear improvement in natural convection heat transfer. Furthermore, a substantial increase in thermal transmittance is observed with an increasing nanoparticle volume fraction. The validation results agree well with both numerical results and experimental data published in the literature.

Heat transfer in radiative hybrid nanofluids over moving sheet with porous media and slip conditions: Numerical analysis of variable viscosity and thermal conductivity

Our current numerical investigation aims to estimate the thermal transport properties of hybrid nanofluids on a moving surface that is being shrinked horizontally. The hybrid nanoparticles consist of alumina (Al2O3) and copper (Cu), suspended in water as the base fluid. The transportation phenomenon takes place in a Darcy-Forchheimer medium, which is a porous material that exhibits thermal radiation, variable viscosity, variable thermal conductivity, Joule heating, viscous dissipation, and the effects of velocity and thermal slip conditions. The governing partial differential equations (PDEs) are converted using suitable similarity transformations into non-linear ordinary differential equations (ODEs). The equations were solved using the shooting technique with the RK-IV algorithm in the MATHEMATICA program. Dimensionless velocity, temperature, skin friction, and Nusselt numbers all provide numerical outcomes. Graphs and tables show the results of an investigation into the influence of different physical characteristics on these numbers. The velocity profile exhibits an upward trend when the velocity slip and nanoparticles volume fraction rise, but a downward trend when the viscosity and Prandtl number are varied. if the thermal slip and variable Prandtl number grow, the temperature profile falls. Conversely, if the nanoparticles volume fraction and variable thermal conductivity increase, the temperature profile increases. The skin friction and Nusselt number exhibit an upward trend as the volume percentage of nanoparticles and the viscosity of the system rise. At a Prandtl number of 6.2 and a nanoparticle volume fraction of 1 %, the Xue model demonstrates a heat transfer rate increase that is 5.32 % superior to the Yamada-Ota model and 3.18 % superior to the Hamilton-Crosser model for nanofluid. In the case of hybrid nanofluid, the Xue model exhibits a 19.01 % superiority over the Yamada-Ota model and 12.197 % superior to the Hamilton-Crosser model.

The Lattice Boltzmann Simulation of Free Convection Heat Transfer of a Carbon-Nanotube Nanofluid in a Triangular Cavity with a Solar Heater

In this paper, the flow and free convection heat transfer of a multi-walled carbon nanotube/water nanofluid in a triangular cavity with a solar heater is studied using the lattice Boltzmann method. The side walls of the cavity are cold and the bottom wall is partially heated by a solar heater, which have a non-uniform temperature distribution. It is assumed that the heating energy is provided by an absorber that is directly exposed to sunlight. Because of the limited variations of density, the Boussinesq approximation is used, which causes the coupling of hydrodynamic and thermal fields. For velocity and temperature distribution functions, a lattice Boltzmann model with two dimensions and nine directions is adopted. The effect of parameters, such as the Rayleigh number, the volume fraction of nanoparticles, and the position of solar heater, on the flow and heat fields is studied. The results show that, for all Rayleigh numbers studied, the Nusselt number increases as nanoparticles volume fraction increases. The addition of 4% nanoparticles causes the average Nusselt number to increase about 11% at low (Ra = 103) and moderate (Ra = 104) Rayleigh numbers and 217% at the high Rayleigh number (Ra = 105). Furthermore, it is shown that for a fixed Rayleigh number, heat transfer can be optimized by adjusting solar heater’s position. This study can provide a useful insight for utilizing solar heaters with non-uniform temperature distribution in triangular cavities.

Porosity and heat transfer analysis of nanofluids due to rotating-stretching disk with Joule heating

The magnetohydrodynamic (MHD), forced convective, rotating flow of nanofluid is investigated induced by eccentric rotations of a unsteady stretching porous disk and that of the fluid at infinity. The fluid is assumed to be incompressible, viscous, and electrically conductible. The disk and fluid away from the disk rotate about non-coincident axes at the same angular velocity. The forced convection is due to the temperature gradient between the uniform temperatures of the disk and that of the fluid far away from the disk. Consideration of the Joule heating as well as viscous dissipation have been taken into account. Nanofluids based on copper, alumina, and titania have also been assumed. Exact solution has been carried out for the velocity field. Numerical solution, on the other hand, is obtained using Crank–Nicolson algorithm for the temperature profiles. Several physical aspects of the investigation are discussed and explained by means of dimensionless parameters, Prandtl number Pr, Eckert number Ec, porosity parameter S, magnetic parameter [Formula: see text] and unsteady stretching parameter. With increasing nanoparticle volume fraction, the velocity profile is reduced, while the thickness of the boundary layer upsurges. As the unsteady parameter C gets higher values, the velocity profile enhanced whereas the temperature profile gets weaker. Fluid temperature decreases as suction parameter S raises.

Effect of slip boundary conditions on unsteady pulsatile nanofluid flow through a sinusoidal channel: an analytical study

A novel analysis of the pulsatile nano-blood flow through a sinusoidal wavy channel, emphasizing the significance of diverse influences in the modelling, is investigated in this paper. This study examines the collective effects of slip boundary conditions, magnetic field, porosity, channel waviness, nanoparticle concentration, and heat source on nano-blood flow in a two-dimensional wavy channel. In contrast to prior research that assumed a constant pulsatile pressure gradient during channel waviness, this innovative study introduces a variable pressure gradient that significantly influences several associated parameters. The mathematical model characterising nano-blood flow in a horizontally wavy channel is solved using the perturbation technique. Analytical solutions for fundamental variables such as stream function, velocity, wall shear stress, pressure gradient, and temperature are visually depicted across different physical parameter values. The findings obtained for various parameter values in the given problem demonstrate a significant influence of the amplitude ratio parameter of channel waviness, Hartmann number of the magnetic field, permeability parameter of the porous medium, Knudsen number due to the slip boundary, volume fraction of nanoparticles, radiation parameter, Prandtl number, and heat source parameters on the flow dynamics. The simulations provide valuable insights into the decrease in velocity with increasing magnetic field and its increase with increasing permeability and slip parameters. Additionally, the temperature increases with increasing nanoparticle volume fraction and radiation parameter, while it decreases with increasing Prandtl number.

Entropy generation analysis of kerosene oil flow with ternary hybrid nanoparticles on the stretchable exponential surface

ABSTRACT In this research, the flow of kerosene oil with ternary hybrid nanoparticles on a stretchable exponential surface has been investigated. There is also a discussion about the entropy analysis of the flow of hydromagnetic radiation by the surface. The ternary hybrid nanofluid (THyNF) contains graphene oxide (GO), magnesium oxide (MgO), and zinc oxide (ZnO) as nanoparticles and kerosene oil as a base fluid. Using useful transformations, differential equations with partial derivatives (PDEs) were transformed into ordinary differential equations (ODEs). Then, the ODEs were solved using the RK5th method. Furthermore, the impacts of parameters like radiation parameter ( Rd ), porosity parameter ( λ ), and volume fraction ( φ ) of THyNF were investigated. Magnetic field (M) and shape factor (SF) on the temperature ( θ ( η )) and velocity ( f ′ η ) profiles have been investigated. Increasing the magnetic field parameter (M) raises the Lorentz force, which produces resistance to fluid flow and reduces fluid velocity ( f ′ η ). The temperature profile ( θ ( η )) rises with increasing magnetic field because the reduced flow rate due to increasing magnetic parameter allows the nanoparticles to transfer more heat. As the nanoparticle volume fraction increases, both the velocity and temperature profiles increase. The effects of M, Rd, SF (shape factor), and λ on entropy generation ( S G ) and Bejan number (Be) have been discussed. Also, the results show that at a fixed value of the magnetic field or the porosity parameter, with the increase in the volume fraction of nanoparticles, the − C fx R e x 12 rises. At a constant value of the φ value of N u x R e x − 12 rises with the increase of the radiation parameter.

Exploring the influence of nanolayer morphology on magnetized tri-hybrid nanofluid flow using artificial neural networks and Levenberg–Marquardt optimization

This study investigates the impact of morphological nanolayers on the thermal conductivity of magnetized tri-hybrid nanofluid flow using artificial neural networks (ANNs) employing the Levenberg–Marquardt (LM-ANN) scheme. Nonlinear partial differential equations (PDEs) are transformed into nonlinear ordinary differential equations (ODEs) using similarity variables. A dataset covering various parameters such as nanolayer thickness, particle radius, magnetic parameter, expansion/contraction ratio, Schmidt number, volume fraction, and Prandtl number is generated using the Bvp5c numerical algorithm. LM-ANN is then used for testing, training, and validation to analyze approximate solutions for individual cases. Histogram analysis, mean square error (MSE), and regression investigations validate the LM-ANN. The proposed approach closely aligns with suggested and reference findings, showing an accuracy level within 10−10 range. Increasing nanolayer thickness leads to higher effective thermal conductivity. The Nusselt number increases notably with higher hybrid nanoparticle volume fraction. Laminar shape consistently exhibits superior heat transfer performance compared to other shapes. Increasing nanoparticle volume fraction enhances the Nusselt number and reduces skin friction coefficients (SFC). Industry recommendations include integrating nanolayer technologies for improved thermal efficiency.

Mixed Convection of an Ag/Water Nanofluid in a Ventilated Square Cavity Containing Cold Blocks of Different Shapes

This research presents the results of a numerical study on mixed convection in a ventilated cavity with a central cold block of varying shapes. The direction of the forced flow of Ag/water nanofluid is perpendicular to the transverse axis (y) of the central cold block. Mixed convection is induced by cooling at the entrance of the ventilated cavity and uniformly heating its bottom wall. The governing equations for the flow of an incompressible Newtonian nanofluid are assumed to be two-dimensional, steady, and laminar. The finite volume method is employed for numerical simulations. A series of calculations are conducted to investigate the effects of key influencing factors: Reynolds number (Re = 100), Richardson number (Ri = 1), and nanoparticle volume fractions (0 ≤ ∅ ≤ 8%) on the enhancement of heat transfer. The impact of four different geometric shapes of the cold obstacle (circular, square, triangular, and elliptical) on fluid flow and heat transfer rate is also explored. The results indicate that an increase in nanoparticle volume fraction enhances the heat exchange rate in the cavity only when the geometric shape of the cold obstacle is circular. This is followed by square and triangular shapes, which approximately yield concordant results, and then the elliptical shape.

An experimental investigation and flow-system simulation about the influencing of silica–magnesium oxide nano-mixture on enhancing the rheological properties of Iraqi crude oil

This study aims to investigate the effects of introducing a 50/50 mixture of silica and magnesium oxide nanoparticles (SNP + MgONP) to the viscosity of Al-Ahdab crude oil (Iraq) at varied concentrations and temperatures. It is observed that the viscosity value drops from 38.49 to 7.8 cP. The highest degree of viscosity reduction is measured to be 56.91% at the maximum temperature of 50 °C and the greatest concentration of 0.4 wt% SM4. The Bingham model can be used to classify the behavior of the crude oil before the Nano-mixture is added. The liquid behavior grew closer to Newtonian behavior once the Nano-mixture was added. Along with a rise in plastic and effective viscosity values, the yield stress value decreases as the concentration of the Nano-mixture increases. The numerical data demonstrate that when the volume proportion of nanoparticles increases, the pressure distribution decreases. Furthermore, as the nanoparticle volume fraction increases, the drag decrease would also increase. SM4 obtains a maximum drag reduction of 53.17%. It is discovered that the sample SM4 has a maximum flow rate increase of 2.408%. Because they reduce the viscosity of crude oil, nanoparticles also reduce the friction factor ratio.

Modeling and analysis of hybrid-blood nanofluid flow in stenotic artery

Current communication deals with the flow impact of blood inside cosine shape stenotic artery. The under consideration blood flow is treated as Newtonian fluid and flow is assumed to be two dimensional. The governing equation are modelled and solved by adopting similarity transformation under the stenosis assumptions. The important quantities like Prandtl number, flow parameter, blood flow rate and skin friction are attained to analyze the blood flow phenomena in stenosis. The variations of different parameters have been shown graphically. It is of interest to note that velocity increases due to change in flow parameter gamma and temperature of blood decreases by increasing nanoparticles volume fraction and Prandtl number. In the area of medicine, the most interesting nanotechnology approach is the nanoparticles applications in chemotherapy. This study provides further motivation to include more convincing consequences in the present model to represent the blood rheology.

Impact of heat source on mixed convection hybrid ferrofluid flow across a shrinking inclined plate subject to convective boundary conditions

Hybrid ferrofluids have exhibited enhanced heat transfer results in numerous applications. Industry demands like inclination sensors and solar water heaters give a new insight into heat transfer problems on the angle of inclination problems. Thus, this paper is motivated to analyse the effect of inclination angle towards mixed convection hybrid ferrofluid flow, including heat sources and convective boundary conditions, on a porous shrink surface. By utilising a similarity transformation, the intricate nature of the partial differential equations (PDEs) is simplified, transforming it into a set of ordinary differential equations (ODEs) and numerically solved in the bvp4c (MATLAB). A positive correlation was obtained between the current model and past researchers. Besides that, the increase in nanoparticle volume fraction improved the skin friction by approximately 14.79% and 15.00% for opposing and assisting flow regions, accordingly. Altering the inclination angle positively impacted growth by approximately 3.28% and 0.0068% on the skin friction and the heat transfer rate, accordingly. The inclusion of a heat source reduced the heat transfer rate by approximately 0.20% and 0.19% for both opposing and assisting flow regions, respectively. Meanwhile, a greater rise in heat transfer rate by approximately 174.48% when the Biot number, Bi rose.

Heat Transfer Enhancement of Convective Casson Nanofluid Flow by CNTs over Exponentially Accelerated Plate

Carbon nanotubes (CNTs) nanofluids are gaining increased popularity among researchers due to their outstanding thermal properties, leading to numerous promising industrial applications. Analytical solutions discovered in the study of CNTs nanofluids, combined with a Casson-type fluid model, are extremely limited. Therefore, a study on the heat transfer analysis of an unsteady and incompressible Casson carbon nanofluid flow is conducted. Human blood-based single-walled carbon nanotubes (SWCNTs) and human blood-based multi-walled carbon nanotubes (MWCNTs) are considered as nanofluids that move beyond an exponentially accelerated vertical plate. A set of dimensional momentum and energy equations, along with their initial and exponentially accelerated boundary conditions, is employed to represent the problem. The transformation of these equations to the dimensionless expression is achieved by using suitable dimensionless variables. The resulting equations are then tackled using Laplace transformation to acquire the analytical solution for temperature and velocity. Figures and tables are produced for a further analysis of temperature and velocity characteristics. The study shows that an increase in nanoparticle volume fraction enhances nanofluid flow and heat transmission, proving highly beneficial for cancer treatment. However, the flow is retarded due to the increment of Casson parameter values, while an enhancement is observed with a superior accelerating parameter.

Thermal analysis of AA7075-AA7072/methanol via Williamson hybrid nanofluid model past thin needle: Effects of Lorentz force and irregular heat rise/fall

Hybrid nanofluids have received remarkable attention due their promising thermal performance compared to conventional nanofluids. The use of hybrid nanofluids is widely found in the pumping power, solar collector, electronic components, coolants in nano devices, and engine applications etc. Such types of applications grabbed the attentionof researchers and scientistswith the aim to understand in depththe problems involving the hybrid nanofluids. Therefore, the primary objective of the present investigationis to investigatethe thermal performance of hybrid nanofluid consisting of asuspension of aluminum alloys (AA7075-AA7072) in methanol-base fluid. The non-Newtonian Williamson fluid flow model under Lorentz force, and irregular heat rise/fall impact past incessantly moving thinneedleis considered. The governingflow equations are solved by bvp4c solver. Results are computed for governing flow parameters such as magnetic field parameter, needle thickness parameter, Weissenberg number, volume fractions, and irregular heat rise/fall constants. Graphs confirm that augmenting values of magnetic field parameter, needle thickness parameter, and Weissenberg number lead to downfall of velocity field but reverse behavior is noticed for increasing nanoparticles volume fraction. A rise in temperature field has been noticed by increasing the magnitude of magnetic field, irregular heat rise/fallparameter, and nanoparticles volume fraction but a decline in fluid temperature occurswithraising theneedle thickness parameter. Detailed discussion about the observed variation in physical properties under pertinent parameters effects is presented. The proposed model is validated by comparison with previouslypublished results.

Study of solar cells structures based on perovskite and nanoparticles

Researchers and scientists working in the field of energy conversion have become interested in the rapidly developing new class of solar cells based on mixed organic-inorganic halide perovskite semiconductors over the past few years. Here we study the transmission of assumed solar cell structures based on nanoparticles and CH3NH3PbI3, CH3NH3PbBr3, and CH3NH3PbI2Br perovskite types by using the transfer matrix method (TMM). We found that as the nanoparticle volume fraction increases, the transmission decreases. Cells doped with aluminum nanoparticles showed the best transmission values. And transmission values in all wavelength ranges are better than those in the range of approximately (300-500).

The radiative composite (NiCr + TC4/H2O) mixture nanofluid flow over a non-linear spinning stretching sheet with the impact of variable Lorenz force and slip condition

Significance The hybrid nanofluid flow is an exciting area of research nowadays for various applications like solar thermal systems, aircrafts, heat exchangers, cooling systems and medical applications. Aim The present research explores the numerical analysis of the three-dimensional spinning flow of a hybrid nano-liquid (NiCr + TC4) over a nonlinear stretching sheet with boundary slip. Methodology The flow equations are governed as partial differential equations (PDEs) and then converted into ordinary differential equations (ODEs) via scaling transformations. In order to compute a solution to the nonlinear ODEs, the Runge-Kutta Fehlberg scheme is used along with MATLAB. Results The findings demonstrate that the temperature field rises with an increase in nanoparticle volume fraction () and falls with an increase in Prandtl number Pr. The wall shear stress in the hybrid nanofluid flow is 1.2% more than viscous fluid flow for different index parameter (n) values. In addition, thermal radiation and magnetic effects widen the study and provide useful insights into the behavior of nano-liquid under various aspects. Novelty This article explores the computational analysis of the 3D rotating flow of (NiCr + TC4)/H2O hybrid nano-liquid across a nonlinear stretching sheet under boundary slip conditions. This flow also takes into account the effect of the variable magnetic field and heat radiation.

Numerical study of unsteady tangent hyperbolic fuzzy hybrid nanofluid over an exponentially stretching surface

The significance of fuzzy volume percentage on the unsteady flow of MHD tangent hyperbolic fuzzy hybrid nanofluid towards an exponentially stretched surface is scrutinized. The heat transport mechanism is classified by Joule heating, nonlinear thermal radiation, boundary slippage, and convective circumstances. Ethylene glycol (EG) as a host fluid along with the nanomaterial’s Cu and {text{Al}}_{{2}} {text{O}}_{{3}} are used for heat transfer analysis is also considered in this investigation. The nonlinear governing PDEs are meant to be converted into ODEs employing appropriate renovations. Then, a built-in MATLAB program bvp4c is employed to acquire the outcome of the given problem. The variation of flow rate, thermal heat, drag force and Nusselt number and their influence on fluid flow with heat transfer have been scrutinized through graphs. An increase in thermal radiation, power law index and nanoparticle volume friction heightens the heat transmission rate. Skin friction is diminished by swelling the power-law index, Weissenberg number, and ratio parameters, whereas it is increased by enhancing the magnetic parameter. The heat transfer rate upsurges with an increase in Weissenberg number and nanoparticle volume fraction. Also, the nanoparticle volume percentage is expressed as a triangular fuzzy number (TFN). The triangular membership function (MF) and TFN are regulated by the chi - {text{cut}} parameter, which has a range of 0 to 1. In comparison to nanofluids, hybrid nanofluids have a higher heat transmission rate, according to the fuzzy analysis. This investigation has applications in the areas of paper manufacturing, metal sheet cooling and crystal growth.

Oscillation and evolution characteristics of nanofluid thermocapillary convection in rectangular cavity

To analyze the oscillation and evolution characteristics of nanofluid thermocapillary convection instability, a two-phase mixture model was utilized to simulate nanofluid thermocapillary convection in a rectangular cavity and investigate the impact of nanoparticle volume fraction on the oscillatory flow. The results indicate that the two-phase mixture model has a lower critical temperature difference compared to the single-phase model, and the oscillation mode exhibits distinct changes for small nanoparticle volume fractions. At a high Marangoni number, the thermocapillary convection displays periodic oscillatory behavior, with the flow field composed of several dynamic convection vortices. An increase in nanoparticle volume fraction results in a decrease in the critical temperature difference, as well as the amplitude and variation range of temperature oscillation. However, the oscillation period shows an approximate linear increase. Furthermore, there is a non-uniform distribution of nanoparticles at the vicinity of solid wall, especially a significant concentration gradient near the side wall.