Nanofluid In Porous Medium Research Articles

Numerical Study of Double-Diffusive Mixed Convection Flow in Channel with Hybrid Nanofluid in Porous Medium

Numerical Study of Double-Diffusive Mixed Convection Flow in Channel with Hybrid Nanofluid in Porous Medium

Study on the preparation of magnetic Janus nanofluids and oil displacement mechanism

Magnetic nanomaterials, known for their eco-friendliness, low toxicity, strong magnetic response, and reusability, have seen significant advancements in enhancing oil recovery. In this study, the surfactant and magnetic Janus nanoparticles (MJNP) were evaluated and optimized through Fourier transform infrared spectroscopy, ζ potential test, scanning electron microscope, emulsion performance evaluation and other analysis, so as to develop magnetic Janus nanofluids (MJNF). Study the flow behavior and enhanced oil recovery mechanism of this nanofluid in porous media through nuclear magnetic resonance (NMR) and numerical simulation methods. The results showed that when the concentration of surfactant (LAD-30) was 0.08%, the maximum water content of emulsion was 80%, and the viscosity increased by more than 90000%. In addition, when the MJNP concentration is 400 ppm or higher, a stable emulsion is formed at 90 °C. NMR experiment shows that through MJNF oil displacement, the oil recovery of small and medium-sized pores is significantly improved by 25.9% and 18.3%, which indicates that high viscosity emulsion can be formed in situ after MJNF injection, thus achieving consistency control. In addition, the numerical simulation results also found that MJNF injection can improve the oil-water saturation in the pore volume and enhance oil phase flow. The research results provide a new understanding for EOR of emulsion flooding.

Entropy generation on inclined magnetize double diffusive convective transportation of radiative Casson nanofluid in porous medium with source/sink

This research intends to investigate the entropy generation on the magnetized double diffusive heat and mass transfer flow of the Casson nanofluid under the influence of an inclined magnetic field in a porous medium. Additionally, the combined impact of heat absorption, chemical reaction, Brownian diffusion, source/sink, and thermophoresis phenomena is also taken care of. The fluid flow involves convective boundary conditions for both temperature and concentration instead of a constant value at the surface. The flow-regulating system involved nonlinear PDEs that are turned into nonlinear systems of ODEs by using scaling variables and then solved this system numerically in Matlab using the bvp4c strategy, which is a collocation technique based on the Lobatto 3-stage FDM algorithm. Graphical representations illustrate the behavior of fluid velocity, entropy generation, concentration, and temperature in response to changes in flow parameters. Physical quantities like skin friction coefficient, Nusselt number, and Sherwood number have been investigated using 2D and 3D plots. Here, we concluded that the inclined magnetic field decimates the flow velocity gradually and greater values of the magnetic field lead to an increased rate of entropy generation. Furthermore, it has been noted that the temperature profile improves as the Brownian motion of particles increases, and the distribution of energy also enhances with larger values of the thermophoresis. The obtained key findings are discussed in a physical manner using graphic representation.

Study on phase transition heat transfer of nanofluids in porous media based on LBM

In this paper, a lattice Boltzmann method is used to simulate the phase transition heat transfer of nanofluid in a miniature heat tube in a porous medium. Based on this, the existing research basis is summarized, the influence of nanoparticles on the thermal properties of the base solution is analyzed, the relevant thermal property prediction model is constructed, and the thermal property parameters of nanofluid are fitted. We generated porous media with different porosity with particle size of 100 micron to 150 microns. Combining the force form proposed by Gong with the exact difference method, the interparticle force is introduced. Based on the improved LBM model and the coupled energy equation, so as to analyze the phase transition heat transfer situation of nanofluids with different thermal properties in porous media.The study shows that nanofluidics can effectively enhance the heat transfer performance of heat pipe equipment.In a certain concentration limit, with the increase of volume concentration, the heat transfer performance of heat pipe is enhanced. The greater the temperature difference between the cold and heat source, that is, the higher the temperature of the heat source, the lower the cold source temperature, the better the heat transfer performance of the heat pipe. For the fluid flow in the porous media region, that is, the turbulent phenomenon that may occur in the porous media, and more vortices occur in the porous media with 40% and 50% porosity. Higher porosity has better heat pipe temperature uniformity.

Non-similar bioconvective analysis of magnetized hybrid nanofluid (Ag + TiO2) flow over exponential stretching surface

Scientists have studied fluid flow over a stretching sheet to explore its potential applications in industries. This study investigates the exponential stretching flow of a bioconvective magnetohydrodynamic (MHD) hybrid nanofluid in porous medium taking into consideration thermal radiations, heat generation, chemical reaction, porosity, and dissipation. Moreover, microorganisms are present in the fluid, so the fluid is more stable, which is crucial in biotechnology, biomicrosystems, and bio-nano coolant systems. Silver and titanium dioxide in a water-based medium are the prototypical nanoparticles. The present study involves a transformation of the governing system into a set of dimensionless, coupled and nonlinear partial differential equations (PDEs) using nonsimilar techniques. The local non-similarity (LNS) technique is used to truncate these equations to ordinary differential equations (ODEs). This technique is also used to estimate transformed equations numerically until the second level of truncation takes place via the bvp4c algorithm, which is a built-in MATLAB solver. Furthermore, tables are provided that presents the drag coefficients, Nusselt numbers, Sherwood numbers, and densities of motile microorganisms. Results show a negative correlation between the velocity and the magnetic field parameter as well as the porosity parameter, as evidenced by a decrease in velocity corresponds to rises in these parameters. The temperature distribution exhibits a positive correlation with the rising values of both radiation parameter and Eckert number. The concentration profiles also exhibit a negative correlation with the increasing values of Lewis and bioconvection Lewis number, chemical reaction parameter, Peclet number and the differences in microbial concentration. This study will improve the future research on hybrid nanofluid regarding industrial applications. There haven't been any previous publications that have investigated the use of this model with the local non-similarity method. The main objective of this article is to enhance the heat transfer performance in a hybrid nanofluid.

SPECTRAL ANALYSIS FOR ENTROPY GENERATION AND IRREVERSIBILITY ON NiZnFe2O4: ENGINE OIL BASED NANOFLUID IN POROUS MEDIUM

This study aims to investigate the impact of volume fraction on entropy generation in a melting stretching/shrinking sheet scenario, considering both first and second-order velocity slips. The investigation focuses on the mixed convective flow of a nanofluid in a porous medium comprising nickel-zinc ferrite and SAE 20W-40 motor oil, which is characterized by Society of Automotive Engineer. Ferrites possess exceptional resistance properties, a crucial consideration in microwave applications. The solution to the derived nondimensional flow governing differential equations is computed using the spectral local linearization method combined with a local non-similarity technique. An assessment of the error is performed to verify the convergence of the numerical approach utilized. A comparison to existing results for specific cases highlights a strong agreement. Various flow-influencing parameters are considered to investigate entropy production, Bejan number, velocity, temperature, heat transport, and skin friction characteristics. The outcomes are presented in graphical form for different parameter values. After simulation, it is perceived that the melting parameter and Darcy number disrupt the entropy by 35.94 and 2.21%, respectively, and enhance the heat transport rate by 27.71 and 2.72%, respectively. This work can be utilized in designing innovative materials for electronics and textiles, in environmental processes like groundwater movement and pollutant dispersion, and in the biomedical field like hyperthermia treatments, tissue engineering, and regenerative medicine.

Radiative Flow of Hybrid MHD Nanofluid in Porous Media about a Concentric Pipe

Radiative Flow of Hybrid MHD Nanofluid in Porous Media about a Concentric Pipe

THERMAL INSTABILITY OF HYDROMAGNETIC JEFFREY NANOFLUIDS IN POROUS MEDIA WITH VARIABLE GRAVITY FOR FREE-FREE, RIGID-RIGID, AND RIGID-FREE BOUNDARIES

This article presents a numerical and graphical examination of thermal instability of hydromagnetic Jeffrey nanofluids in porous media with variable gravity for free-free, rigid-rigid, and rigid-free boundaries by using Galerkin technique and normal mode analysis. The Darcy model is employed. Four different gravity variable parameters: h(z) = -(e<sup>z</sup> - 1); exponential, h(z) = -z<sup>2</sup>; parabolic, h(z) = -z; and linear, h(z) = z are taken, and their effects on the Jeffrey parameter, magnetic field, moderated diffusivity ratio, porosity of porous media, Lewis number, and nanoparticle Rayleigh number on stationary convection have been calculated numerically and graphically shown for all three boundary conditions, namely free-free, rigid-rigid, and rigid-free. The necessary conditions for frequencies of the oscillatory mode under all three boundaries have been calculated. According to our research, positive linear gravity parameters make the system unstable for all three boundary conditions, but exponential gravity parameters are superior at stabilizing stationary convection for all three boundary conditions.

An exergy-economic analysis of a concentrated photovoltaic-thermal system with phase change materials cooled by a nanofluid in porous media

An exergy-economic analysis of a concentrated photovoltaic-thermal system with phase change materials cooled by a nanofluid in porous media

Thermal instability of rotating Jeffrey nanofluids in porous media with variable gravity

It is investigated how changes in gravity affect the thermal instability rotating Jeffrey nanofluids in porous media. Along with the Galerkin method and normal mode approach, the Darcy model is used. The distinct variable gravity parameters taken in this paper are: h(z)=z2-2z, h(z)=-z2, h(z)=-z and h(z)=z and their effects on the Jeffrey parameter, Taylor number, moderated diffusivity ratio, porosity of porous media, Lewis number and nanoparticle Rayleigh number on stationary convection have been scrutinized and graphically shown. Our finding demonstrates that varying gravity parameter h(z)=z2-2z has more stabilising impact on stationary convection. We have also discovered the necessary condition for overstability in the instance of oscillatory convection for this problem.

Synthesis of core-shell fluorescent silica nanoparticles with opposite surface charges for transport studies of nanofluids in porous media

Silica nanoparticles (SiNPs) have been extensively studied as additives in injected fluids for enhanced oil recovery. Typically, surfactants are used to increase colloidal stability, but little is known about the transport of SiNPs in porous media because of the scarcity of reliable quantification techniques. In this study, we investigated the use of core-shell silica-based fluorescent SiNPs as tracers for transport studies of nanofluids containing surfactants. Two synthetic strategies were used to obtain distinct structures of fluorescent SiNPs with similar cores but different surface groups, namely silanol and aminopropyl, comparable to those reported in nanofluid applications. The synthesised NPs had comparable sizes and morphologies but displayed opposite surface charges when dispersed in aqueous solutions. The main colloidal properties and time stability of the fluorescence response were determined in the presence of an anionic surfactant and compared with regard to their potential use as tracers for transport studies. Both fluorescent SiNPs were successfully quantified in the effluent after flowing through the glass bead column. The SiNP-containing aminopropyl surface groups showed the greatest stability and lowest adsorption compared with those grafted with silanol groups. We attribute this behaviour to the effect of stronger attractive interactions between the NPs and surfactants. The potential of these fluorescent NPs as sensitive tracers for transport and adsorption studies in nanofluids containing surfactants was demonstrated.

A Comprehensive Review of Nanofluid Heat Transfer in Porous Media

In the present paper, recent advances in the application of nanofluids in heat transfer in porous materials are reviewed. Efforts have been made to take a positive step in this field by scrutinizing the top papers published between 2018 and 2020. For that purpose, the various analytical methods used to describe the flow and heat transfer in different types of porous media are first thoroughly reviewed. In addition, the various models used to model nanofluids are described in detail. After reviewing these analysis methods, papers concerned with the natural convection heat transfer of nanofluids in porous media are evaluated first, followed by papers on the subject of forced convection heat transfer. Finally, we discuss articles related to mixed convection. Statistical results from the reviewed research regarding the representation of various parameters, such as the nanofluid type and the flow domain geometry, are analyzed, and directions for future research are finally suggested. The results reveal some precious facts. For instance, a change in the height of the solid and porous medium results in a change in the flow regime within the chamber; as a dimensionless permeability, the effect of Darcy's number on heat transfer is direct; and the effect of the porosity coefficient has a direct relationship with heat transfer: when the porosity coefficient is increased or decreased, the heat transfer will also increase or decrease. Additionally, a comprehensive review of nanofluid heat transfer in porous media and the relevant statical analysis are presented for the first time. The results show that Al2O3 nanoparticles in a base fluid of water with a proportion of 33.9% have the highest representation in the papers. Regarding the geometries studied, a square geometry accounted for 54% of the studies.

Electrohydro dynamics convection in dielectric rotating Oldroydian nanofluid in porous medium

An electrically conducting nanofluid saturated with a uniform porous media has been tested to determine how rotation affects thermal convection. Utilizing the Oldroydian model, which incorporates the specific effects of the electric field, Brownian motion, thermophoresis, and rheological factors for the distribution of nanoparticles that are top- and bottom-heavy, one may use linear stability theory to ensure stability. Analysis and graphical representation of the effects of the AC electric field Rayleigh number, Taylor number, Lewis number, modified diffusivity ratio, concentration Rayleigh number, and medium porosity are provided for both bottom-heavy and top-heavy distribution.

The Influence of Saturated and Bilinear Incidence Functions on the Dynamical Behavior of HIV Model Using Galerkin Scheme Having a Polynomial of Order Two

Mathematical modelling has been extensively used to measure intervention strategies for the control of contagious conditions. Alignment between different models is pivotal for furnishing strong substantiation for policymakers because the differences in model features can impact their prognostications. Mathematical modelling has been widely used in order to better understand the transmission, treatment, and prevention of infectious diseases. Herein, we study the dynamics of a human immunodeficiency virus (HIV) infection model with four variables: S (t), I (t), C (t), and A (t) the susceptible individuals; HIV infected individuals (with no clinical symptoms of AIDS); HIV infected individuals (under ART with a viral load remaining low), and HIV infected individuals (with two different incidence functions (bilinear and saturated incidence functions). A novel numerical scheme called the continuous Galerkin-Petrov method is implemented for the solution of the model. The influence of different clinical parameters on the dynamical behavior of S (t), I (t), C (t) and A (t) is described and analyzed. All the results are depicted graphically. On the other hand, we explore the time-dependent movement of nanofluid in porous media on an extending sheet under the influence of thermal radiation, heat flux, hall impact, variable heat source, and nanomaterial. The flow is considered to be 2D, boundary layer, viscous, incompressible, laminar, and unsteady. Sufficient transformations turn governing connected PDEs into ODEs, which are solved using the proposed scheme. To justify the envisaged problem, a comparison of the current work with previous literature is presented.

Stability analysis of mixed convection in a porous horizontal channel filled with a Newtonian Al2O3/Water nanofluid in presence of magnetic field and thermal radiation

• Stability analysis of mixed convection of Newtonian nanofluid in porous media. • Magnetic field and thermal radiation are taken into consideration in the problem. • Prandtl, and Richardson numbers maintain instabilities in convective flow . • Magnetic field, thermal radiation and medium's permeability stabilize the flow. • Nanoparticles into the base fluid increases the inertia of the fluid. This paper investigates a stability analysis of mixed convection of A l 2 O 3 / W a t e r nanofluid in a horizontal porous channel heated from below and cooled from above. Certain effects such as magnetic field and thermal radiation are taken into consideration. The permeability of the porous medium is described by Darcy's model. Starting from the Navier-Stokes equations to which the energy and Maxwell equations are coupled and under the assumption of an analysis in normal mode, a system of differential equations with eigenvalues governing the stability of the flow is derived and solved numerically by the spectral collocation method. The effects of the magnetic field, thermal radiation, volume fraction of nanoparticles, permeability of the medium and many other important parameters are presented and analyzed. The results show that the introduction of the nanoparticles into the base fluid increases the inertia of the fluid, which dampens the disturbances. Among the different geometric shapes of nanoparticles, the blade shape has a more stabilizing effect on the stability of the convective flow. It is also shown that oxide-type nanoparticles have a more stabilizing effect compared to metallic-type nanoparticles on small wave number disturbances. In the case of large wave numbers, the opposite is observed. Parameters such as Prandtl number and Richardson number maintain instabilities in convective flow. On the other hand, the magnetic field, the thermal radiation and the permeability of the porous medium affect the stability of the convective flow and all have stabilizing effects, which makes it possible to control the mixed convection of nanofluid.

Nanoparticle's radius effect on unsteady mixed convective copper-water nanofluid flow over an expanding sheet in porous medium with boundary slip

Nanofluid and its higher thermal performance are displayed more promising outcomes when the flow medium is assumed to be a porous medium. Additionally, the radius size of nanoparticles plays a significant role in enhancing this thermal performance. So, present analysis aims to investigate the time-dependent flow of copper-water nanofluid in porous medium on an expanding sheet in presence of buoyancy force and slip phenomenon under various nanoparticle's radii. The flow is assumed to be boundary layer, two-dimensional, viscous, incompressible, laminar and unsteady. Governing coupled PDEs are changed into ODEs by suitable transformations and the converted ODEs are solved numerically. The study discloses that velocity rises with larger radius of nanoparticles and enlargement in assisting buoyancy force, whereas with unsteadiness of the flow, less permeability of porous material and boundary slip it drops. Also, magnitude of wall-drag force grows with larger radius of nanoparticles and flow unsteadiness. Importantly, for higher value of nanoparticle's radius surface-drag force massively enhances when permeability of porous medium is less. Temperature increment exhibits for boundary slip and less permeability of the porous material. Lastly, wall cooling rate intensifies with flow unsteadiness and higher value of nanoparticle's radius.

Unsteady mixed convective stagnation point flow of hybrid nanofluid in porous medium

Unsteady mixed convective stagnation point flow of hybrid nanofluid in porous medium

Performance enhancement of an evacuated tubes solar collector using Forchheimer’s saturated porous media with embedded nanofluid

The evacuated tube solar collector is a proper choice for converting solar energy into heat since it is efficient, practical, and cost-effective. In the current study, the role of nanofluid in porous medium was numerically investigated to improve the performance of a solar collector model and the potential to store energy. The governing equations for the suggested model were solved analytically in the fully developed region using the Forchheimer model. The investigation of the impact on temperature fluctuation in the solar collector was done by considering several factors such as medium porosity, pore diameter, nanoparticles with respect to the solid volume ratio, system pressure, and conduit radius. The governing equations for the entrance region were expressed in a non-dimensional form and solved using the finite difference method (FDM), with the resulting non-dimensional differential equation solved using MATLAB software. Various parameters, such as Prantel number (Pr) and fluid velocity, were examined, and the findings were shown in various diagrams. For the fully developed region, an analytical solution was obtained, and the findings were presented using the Mathematica® software. The results demonstrate that utilizing nanofluid and porous media improves the performance of the evacuated tube when compared to sole use of water. It was found that the temperature difference across the solar tube was enhanced by 10%–20%. In addition to that, the performance of the evacuated tube solar collector showed around 10% enhancement in the obtained temperature difference in cold months, when nanofluids were added. Also, the comparison between nanofluids using Forchheimer model shows that the best nanofluid was AL2O3. The best results had a significant effect on the solid volume fraction rate of nanoparticles in nanofluids obtained at low Reynolds and Prandtl numbers. Where the higher the fraction, the higher the heat transfer, the higher the resulted temperature.

Analysis of multilayer convective flow of a hybrid nanofluid in porous medium sandwiched between the layers of nanofluid

AbstractAgBr acts as a good sensitizer for titanium oxide, hence TiO2–AgBr nanoparticles exhibit high photocatalytic activity which helps decompose methyl orange under visible light irradiation. Methyl orange is a chemical compound that is hard to degrade and has high stability. It is photoreactive and can capture photons from the sun and is highly used as a light harvester in solar cells, hence, it is used in solar applications. In view of this, the present article deals with the analysis of heat transfer in a multilayer flow of two immiscible nanofluids in a vertical channel that finds application in the fields of solar reactors, electronic cooling, and so on. The mathematical model involving the effect of thermal radiation and the presence of heat source is in the form of a system of ordinary differential equations. This system of equations is simplified using the differential transform method‐Padé approximant and the resulting equations are solved algebraically. It is observed that the temperature of the coolant does not reach its saturation point faster due to the presence of different base fluids that differ in their thermal conductivity. This helps in maintaining the optimum temperature of the system.

Comparative Analysis MHD Bioconvective Flow of Micropolar Nanofluid in Porous Medium

The present study dealt with heat and mass transfer rate, and motile micro-organisms for convective micropolar nanofluid flow in a porous medium. The nanofluid contains the influence of both Brownian motion and thermodiffusion (thermophoresis). The problem considered finds applications in the areas of engineering such as reducing greenhouse effects and in the pharmaceutical applications enhancing mixing and slowing down settling particles can be mentioned. The numerical results are obtained and discussed. The results obtained suggest that micropolar fluids enhance the flow and decrease the temperature, nanoparticles concentration and gyrotactic microorganisms concentration profiles compared to viscous fluid. It is also noted that Hall parameter increases skin friction, the heat transfer rate, the mass transfer rate and density of the motile microorganisms.