Copper Water Nanofluid Research Articles

Dufour and Soret effects on MHD squeezed nanoliquid flow between parallel plates by differential transform method

Purpose This paper aims to examine the Dufour and Soret combined effects on the study of two-dimensional squeezed flow of copper water nanofluid between parallel plates along with applied (external) magnetic field. Impact of higher order chemical reaction is also considered. Design/methodology/approach The nonlinear partial differential equations (PDEs) are changed into system of ordinary differential equations (ODEs) by employing suitable similarity transformations. These transformed ODEs are then solved by means of a semianalytical method called differential transform method (DTM). Effects of several changing physical parameters on fluid flow, temperature and concentration have been deliberated through graphs. Findings It is observed that Dufour and Soret numbers are directly related to temperature profile and a reverse trend was observed in the concentration profile. Temperature enhancement is perceived for the enhanced Dufour number. Enhancement in Dufour number shows a direct association with Sh and Nu for all values of squeezing parameter. Practical implications The combined Dufour and Soret effects are used in separation of isotopes in mixture of gases, oil reservoirs and binary alloys solidification. The squeeze nanoliquid flow can be used in the field of composite material joining, rheological testing and welding engineering. Social implications This study is mainly useful for geosciences and chemical engineering. Originality/value The uniqueness in this research is the study of the impact of cross diffusion on chemically reacting squeezed nanoliquid flow with the chemical reaction order more than one in the presence of applied magnetic force using a semianalytical procedure, named DTM.

An approach for tailoring the interfacial thermal conductance of copper-water nanofluids through ion additions and the underlying mechanism

Smaller Kapitza resistance is known to be the most crucial factor responsible for the larger thermal conductivity of nanofluids. But what the underlying mechanism is remains ambiguous. Non-equilibrium molecular dynamics simulations were performed in the present work to examine the effect of ionic addition on the Kapitza resistance of Cu-water nanofluids. The temperature profile indicates that the concentration and type of the additive slightly affects the thickness of the interfacial layer, but the temperature drops significantly. For concentrations of 1 M, the interfacial thermal conductance (ITC, the reciprocal of the Kapitza resistance) of Cu-water with NaCl, NaOH and HCl increases by 48.1 %, 29.2 % and 22.6 % respectively, compared to that without additives. The greatest ITC improvement of 123.7 % can be achieved by adding 3 M NaCl. The density profiles of Cu-water nanofluids with various additives suggest that the changes in the interfacial structure are primarily due to the positions of the added cations and anions. It is important to note, however, that the ITC is closely related to the orderliness of the interfacial layer and the matching of the phonon density of states, since the addition of NaCl can increase the PDOS at lower frequencies 1–5 THz, where that for the Cu nanoparticle appears. The findings provide a practical approach to tailor the thermal conductivity of nanofluids by the addition of appropriate ions.

Aspects of double slip on multiphase inclined channel flow of Casson and Cu-nanofluid

The key aspect of this study is to inspect the entropy generation (EG) of heat and momentum transport within two immiscible Casson and nanofluid (NF) with mass diffusion of copper nanomaterials in an inclined channel (IC) with thermal and velocity slips. The IC is divided into two regions. Region-I contains the Casson fluid (CF) whereas Region II is occupied with copper-water NF. Moreover, the effects of Lorentz force are also taken in region II having copper-water NF. The mathematical model is solved by employing the perturbation method. The behavior of different aspects, i.e., mass diffusion of copper nanomaterials, Lorentz force, velocity and thermal slips on EG, and transport of mass and heat are presented in graphs and tabular forms. Furthermore, the numerical outcomes of friction at the walls and the rate of heat transport are presented in tabular form. Our results show that the EG and the rate of EG decline when the dispersion of nanomaterials is increased. The velocity and temperature decline when Lorentz force is increased in Region II. Furthermore, temperature augments with the rise in CF parameter and thermal slip parameters whereas velocity also increases with the rise in velocity slip parameters. So, the thermal performance can be enhanced in an IC by using blood fluid in one phase and thermal slips at the walls.

Analysis of Heat Transfer for the Copper–Water Nanofluid Flow through a Uniform Porous Medium Generated by a Rotating Rigid Disk

This study theoretically investigates the temperature and velocity spatial distributions in the flow of a copper–water nanofluid induced by a rotating rigid disk in a porous medium. Unlike previous work on similar systems, we assume that the disk surface is well polished (coated); therefore, there are velocity and temperature slips between the nanofluid and the disk surface. The importance of considering slip conditions in modeling nanofluids comes from practical applications where rotating parts of machines may be coated. Additionally, this study examines the influence of heat generation on the temperature distribution within the flow. By transforming the original Navier–Stokes partial differential equations (PDEs) into a system of ordinary differential equations (ODEs), numerical solutions are obtained. The boundary conditions for velocity and temperature slips are formulated using the effective viscosity and thermal conductivity of the copper–water nanofluid. The dependence of the velocity and temperature fields in the nanofluid flow on key parameters is investigated. The major findings of the study are that the nanoparticle volume fraction significantly impacts the temperature distribution, particularly in the presence of a heat source. Furthermore, polishing the disk surface enhances velocity slips, reducing stresses at the disk surface, while a pronounced velocity slip leads to distinct changes in the radial, azimuthal, and axial velocity components. The study highlights the influence of slip conditions on fluid velocity as compared to previously considered non-slip conditions. This suggests that accounting for slip conditions for coated rotating disks would yield more accurate predictions in assessing heat transfer, which would be potentially important for the practical design of various devices using nanofluids.

Gyrotactic Mixed Bioconvective Flow of Copper–Water Nanofluid Past a Rotating Cone with Non-uniform Heat Source and Activation Energy

Gyrotactic Mixed Bioconvective Flow of Copper–Water Nanofluid Past a Rotating Cone with Non-uniform Heat Source and Activation Energy

Numerical and statistical analyses of three-dimensional non-axisymmetric Homann's stagnation-point flow of nanofluids over a shrinking surface

Nanofluids, which are known for their superior heat transfer properties, have become indispensable in real-world applications. This underscores the critical importance of comprehensive understanding, which forms the core of this study. The goal of this study is to scrutinize Homann's non-axisymmetric stagnation-point flow over a shrinking surface of various single-phase water-based nanofluids (water-copper, water-alumina, and water-titanium dioxide) in a three-dimensional (3D) system. The model formulations are derived into ordinary differential equations via sophisticated similarity variables that satisfy the continuity equation. A boundary value problem solver (bvp4c) with a finite difference method in MATLAB is adapted to carry out numerical calculations while the response surface methodology (RSM) in MINITAB is used to statistically analyze the solution. The opposing flow created by the shrinking surface within a certain degree of shrinkage leads to the formation of two distinct alternative solutions. The current study offers two alternative solutions for boundary layer flow control modeling. However, only the first solution is tested to be stable. The critical point for boundary layer bifurcation is identified, to efficiently manage the flow. Water-copper nanofluid has been proven to perform better in heat transfer than water-alumina and water-titanium dioxide nanofluids. The 2 % volume fraction of copper provides better heat transfer compared to 1 % volume fraction in the present configuration of the flow system. The response optimizer via RSM also validates that the heat transfer performance of copper nanofluid is maximized when the volume fraction of copper is set at a high level with a low shear-to-strain rate.

Numerical and optimization study of turbulent water-copper nanofluid flow in a heat exchanger in power plant with conical rings: Investigating conical ring hole diameter's influence

This paper presents a numerical investigation of turbulent nanofluid flow in a power plant heat exchanger using conical rings. In this paper focus on varying conical ring hole diameters and their impact on key parameters. Utilizing artificial intelligence techniques, the finite element method (FEM), and the RNG k-epsilon model, analyzed pressure drop, thermal entropy, frictional entropy, and total entropy while varying distances between turbulators (80 mm to 180 mm) and turbulator lengths (45 mm to 60 mm). The results show that the smallest turbulator length and diameter, with an inter-turbulator distance of 145 mm, generate the highest frictional entropy (72 % increase). Smaller distances between turbulators with larger turbulator dimensions result in the smallest pressure drop. Increasing hole diameter significantly reduces thermal (98.7 %), frictional (72.5 %), and total entropy (98.5 %). These findings offer insights for optimizing power plant heat exchanger design using nanofluids and conical turbulators.

Study of flow and heat transfer performance of nanofluids in curved microchannels with different curvatures

This study focuses on investigating the flow and heat transfer characteristics of Copper-water nanofluids (Cu-H2O) and water in microchannels with varying curvatures. The results reveal that Cu-H2O nanofluids demonstrate superior heat transfer performance compared to pure water in all four microchannels. Moreover, curved microchannels exhibit higher heat transfer performance than straight microchannels, regardless of whether the flow is laminar or turbulent. The heat transfer performance improves with increasing channel curvature, volume fraction of nanoparticles, and decreasing particle size. During laminar flow, the impact of curvature on heat transfer performance is more significant. However, during turbulent flow, variations in volume fraction have a greater influence on heat transfer performance compared to changes in curvature and particle size reduction. While larger volume fractions and higher curvatures increase flow resistance, this relationship is less pronounced for turbulent flow as Reynolds number and volume fraction increase. It is worth noting that the comprehensive heat transfer performance index does not consistently improve with increasing curvature, and sometimes straight microchannels outperform curved microchannels with specific curvatures. Additionally, curved microchannels exhibit a smaller average field synergy angle (FSA) compared to straight microchannels, indicating better synergy between the flow field and temperature field. The FSA also shows a relatively uniform distribution of local field synergy angles throughout the flow region in curved microchannels. Furthermore, the FSA decreases as the curvature increases.

Heat source and radiation effects on MHD flow of Copper-Water nanofluid over exponential stretching surface with slip

This study explores the combined impacts of heat source and radiation on the boundary layer of magnetohydrodynamic stagnation point flow of a copper–water nanofluid over an exponentially stretching slippery surface. The fundamental governing partial differential equations of mass, momentum, and energy in the model are transformed into dimensionless ordinary differential equations through similarity transformations. These derived ordinary differential equations are then converted into an initial value problem and solved numerically using the Runge-Kutta-Fehlberg technique. The results are analyzed for parameters relevant to engineering and industrial applications, encompassing velocity, temperature, skin friction, and Nusselt number. The analysis reveals that an increase in the values of heat source and radiation parameters leads to higher temperature and Nusselt number in the copper–water nanofluid flow. Conversely, an increase in the magnetic parameter results in a decrease in the temperature profile. These findings are compared with other reported results for a special case and are subsequently presented graphically and discussed in the context of engineering and industrial applications.

Numerical study on mixed convection heat transfer of copper-water nanofluid in a porous cavity with an isothermal solid block in local thermal non-equilibrium

This manuscript reports a numerical study on mixed convection heat transfer of Cu-water nanofluid in a porous cavity with an isothermal solid block in the state of local thermal non equilibrium. The set of governing equations are solved by finite volume method combined with SIMPLE algorithm. Through streamlines and isothermal contour plots as well as the average Nusselt number, the impact of various parameters like the nanoparticle concentration, Richardson number, Darcy number, and inter phase heat transfer coefficient is highlighted. The main findings indicate that the Local thermal non-equilibrium state (H = 1, 10) produces the maximum heat transfer rate than the local thermal equilibrium state (H = 1000).

Irreversibility and nanomaterials shape consequences on peristalsis of magneto hybrid nanofluid via curved configuration with homogeneous–heterogeneous chemical reactions

Over the last decade, research on nanofluids has grown at a breakneck pace. As part of their nanofluid research, researchers have recently attempted to use hybrid nanofluids, made by combining different nanomaterials. The novelty of this analysis is to inspect the consequences of entropy generation on the peristalsis of a hybrid nano-liquid via a curved conduit with homogeneous and heterogeneous chemical reactions. Hybrid nanofluid is formed of copper and iron oxide nanomaterials added to water. Furthermore, the simplified model also considered the Hall current, viscous dissipation, and electrical resistance heating effects. The Hamilton–Crosser thermal conductivity model is used to study the nanomaterials shape effects (i.e. sphere, platelet, and blade) on the thermal features of hybrid nano-liquids. Mathematical expressions for the flow problem are simplified by employing the small wave and Reynolds numbers assumptions, which are then resolved analytically and numerically. Analytical results are used to scrutinize the impacts of several included quantities on the flow and thermal characteristics, chemically reactive concentration, and entropy creation. It is found that with a rise in Hartmann number, the velocity reduces, whereas an improvement is noted in temperature and entropy production for large values of Hartmann number. The noteworthy discoveries indicate that hybrid nano-liquids exhibit enhanced thermal efficiency when compared to conventional nanofluids. Specifically, the introduction of a small quantity of ferrous oxide nanoparticles into the copper–water nanofluid led to less than 2% increase in the thermal transport rate. Additionally, it was observed that spherical-shaped nanoparticles generate more heat in comparison to platelets and blade-shaped nanoparticles. Furthermore, the homogenous reaction parameter and Schmidt number lead to a drop in the concentration profile.

Approaches through effects of Hall current, nanoparticle radius, inter-particle spacing and multiple slips on the suspension of copper-water nanofluid with gyrotactic microorganisms

In this comprehensive study, the dynamic behavior of a copper-water nanofluid infused with gyrotactic microorganisms, focusing on the effects of Hall current, nanoparticle radius, inter-particle spacing, and multiple slip mechanisms is investigated. Through advanced numerical simulations and rigorous analysis, intricate relationships between the parameters and the suspension’s characteristics are uncovered. Comparison of the present results show a good agreement with the published results. The research findings unveil the potential for fine-tuning transport processes, manipulating thermal properties, and controlling dispersion and aggregation in nanofluids. These insights hold promise for a wide array of applications, from enhancing heat exchangers and cooling systems to pioneering biomedical devices utilizing gyrotactic microorganisms for targeted drug delivery and sensing. This study not only advances the fundamental understanding of nanofluid dynamics but also paves the way for innovative developments across various scientific and engineering domains.

Double diffusive MHD squeezing copper water nanofluid flow between parallel plates filled with porous medium and chemical reaction

Purpose This paper aims to explore the double diffusive magneto-hydrodynamic (MHD) squeezed flow of (Cu–water) nanofluid between two analogous plates filled with Darcy porous material in existence of chemical reaction and external magnetic field. Design/methodology/approach The governing nonlinear equations are transformed into ordinary differential equations by means of similarity transforms, and the coupled mass and heat transference equations are resolved analytically with the application of differential transform method (DTM). The effects of different relevant parameters on velocity, temperature and concentration, including the squeeze number, magnetic parameter, Biot number, Darcy number and chemical reaction parameter, are illustrated with figures. In addition, for various parameters, the local skin friction coefficient, local Nusselt number and local Sherwood number are computed and are graphically displayed. Findings It is observed that the squeeze number has a direct relationship with Sherwood number and an inverse relationship with skin friction as Biot number increases. With enhanced Biot numbers, the temperature value increases during both squeeze and non-squeeze moments, but the temperature values are higher for squeeze moments compared to the other case. Practical implications This research has potential applications in various large-scale enterprises that might benefit from increased productivity. Social implications The results are useful to thermal science community. Originality/value Unique and valuable insights are provided by studying the impact of chemical reaction on double diffusive MHD squeezing copper–water nanofluid flow between parallel plates filled with porous medium. In addition, this research has potential applications in various large-scale enterprises that might benefit from increased productivity.

Comparative analysis of power-law stretching and suction/blowing over three-dimensional Darcy–Forchheimer copper–water nanofluid flow

Comparative analysis of power-law stretching and suction/blowing over three-dimensional Darcy–Forchheimer copper–water nanofluid flow

Heat transfer analysis of MHD viscous nanofluid flow over a nonlinearly stretching sheet with heat source/sink: A numerical study

The present study analyses the magnetohydrodynamics (MHD) viscous nanofluid flow past a nonlinearly stretching sheet embedded in a porous medium under the influence of heat generation and thermal radiation. Further, variable magnetic field as well as variable permeability is used instead of constant magnetic field and permeability due to many therapeutic applications, which makes them distinctive and practically helpful. The MHD viscous flow and heat transfer equations have been generated as coupled second-order nonlinear partial differential equations using a mathematical model that resembles the physical flow problem. The partial differential equations governing the flow problems are reduced to ordinary differential equations via similarity variables. The reduced equations are then solved by Runge–Kutta–Fehlberg’s scheme with shooting method by the help of MATLAB software. The result obtained reveals that enhancing the heat generation parameter, porosity parameter, and radiation parameter upsurges the temperature of the nanofluid, whereas the magnetic parameter shows the reverse effect in the case of velocity distribution. Nusselt number decreases at the rate of 2.6147% for copper–water nanofluid when increased from 0 to 0.05. Silver nanoparticles have the highest heat transfer as compared to other nanoparticles. Because of this, silver nanoparticles are the most effective thermal conductors for increasing the effectiveness of heat storage in phase transition materials.

Molecular dynamics simulation of ultrasound cavitation occurring in copper–water nanofluid

It is necessary to reveal the impact of nanoparticles on ultrasonic cavitation phenomena in nanofluids, which is conducive to the heterogeneous nucleation applications of ultrasonic cavitation. In this work, the ultrasonic cavitation processes in pure water and nanofluids were simulated by molecular dynamics. Then, the effect of nanoparticles on ultrasonic cavitation was investigated by adding alternate positive and negative pressure waves. After that, the formation of critical bubbles in cavitation and the collapse of nanobubbles by shock waves were studied by using Voronoi mosaic method and rigid body model, respectively. Finally, the regenerated nanobubbles were analyzed after the collapse of nanobubbles. The results show that the nanoparticles could promote the formation of nanobubbles, and consequently, the nano-jets and nanoparticles movement occur during the collapse of nano-bubbles. Additionally, more tiny cavities generated after the collapsing of nanobubbles and the number of nanobubbles during second cycle will be larger than that of the first cycle. As a result, some of these cavities promote the generation of multiple ultrasonic cavitation bubbles in the subsequent ultrasonic cycle. This leads to the chain reaction effect of ultrasonic cavitation phenomenon occurring in nanofluids.

Nanofluid Heat Transfer and Flow Characteristics in a Convex Plate Heat Exchanger Based on Multi-Objective Optimization

Convex plate heat exchangers have drawn much interest across various industries thanks to their improved heat transfer efficiency and compact design. Research examines the characteristics of convex plate heat exchangers in this study through a combined experimental and numerical method. A mixture that contains water and copper nanoparticles is known as a copper-water nanofluid. A multi-objective optimization technique is used in this study to give an experimental and numerical evaluation of the nanofluid heat transfer and flow properties of a convex plate heat exchanger. Numerical execution is performed using the ANSYS software, and the materials for the convex plate are copper and water. This study aims to improve the nanofluid flow performance and the heat transfer efficiency of heat transfer of the heat exchanger by optimizing its design parameters. The heat exchanger’s temperature distributions and pressure drops are measured using an experimental setup, and numerical execution is used to forecast the heat transfer coefficients and pressure losses. The ideal design parameters that concurrently maximize heat transmission and minimize pressure drop are discovered using a multi-objective optimization technique. The findings of this study enable the creation of more effective and affordable heat exchanger layouts for various industrial applications by offering useful insights into the transfer of heat and flow behavior of the convex plate heat exchanger.

Hiemenz flow for a micropolar nanofluid with bidirectional flexible surface and heat transfer

The steady Hiemenz stagnation-point flow of a flexible membrane moving bidirectionally, for a micropolar copper–water nanofluid model is studied. The flow field is a unison of wall transpiration, velocity slip and stagnation-point flow for a 2D case, generating unique or dual form of exact similarity solutions. The results reveal that a unique solution exists for the stretching sheet, depending entirely on a given set of parameters, while two solutions fall within the physically recognizable region for the case of a shrinking sheet. A set of new exact solutions characterized by the stretching/shrinking strength parameter d are also found with d considering different values. It is found that the numerical integration for skin friction, couple stress friction and temperature gradient leads to twofold solutions.

Cross-Diffusion and Higher-Order Chemical Reaction Effects on Hydromagnetic Copper–Water Nanofluid Flow Over a Rotating Cone in a Porous Medium

Spin coating of engineering components with advanced functional nanomaterials which respond to magnetic fields is growing. Motivated by exploring the fluid dynamics of such processes, a mathematical model is developed for chemically reactive Cu–H2O magnetohydrodynamic (MHD) nanofluid swirl coating flow on a revolving vertical electrically insulated cone adjacent to a porous medium under a radial static magnetic field. Heat and mass transfer is included and Dufour and Soret cross-diffusion effects are also incorporated in the model. Thermal and solutal buoyancy forces are additionally included. To simulate chemical reaction of the diffusing species encountered in manufacturing processes, a higher-order chemical reaction formulation is also featured. Via suitable scaling transformations, the governing nonlinear coupled partial differential conservation equations and associated boundary conditions are reformulated as a nonlinear ordinary differential boundary value problem. MATLAB-based shooting quadrature with a Runge–Kutta method is deployed to solve the emerging system. Concentration, temperature and velocity variations for various nondimensional flow parameters have been visualized and analyzed. In addition, key wall characteristics, i.e., radial and circumferential skin friction, Nusselt number and Sherwood number, have also been computed. Validation with earlier studies is also included. The simulations indicate that when compared to a lower-order chemical reaction, a higher-order chemical reaction allows a greater rate of heat and mass transfer at the cone surface. Increasing Dufour (diffuso-thermal) and Soret numbers generally reduces radial and circumferential skin friction and also Nusselt number, whereas it elevates the Sherwood number. Both skin friction components are also suppressed with increasing Richardson number. Strong deceleration in the tangential and circumferential velocity components is induced with greater magnetic field.

Supervised machine learning techniques for optimization of heat transfer rate of Cu-H2O nanofluid flow over a radial porous fin

PurposeThe purpose of this paper is to study the thermal behavior of radial porous fin surrounded by water-base copper nanoparticles under the influence of radiation.Design/methodology/approachIn order to optimize the response variable, the authors perform sensitivity analysis with the aid of response surface methodology (RSM). Moreover, this study enlightens the applications of artificial neural networks (ANN) for predicting the temperature gradient. The governing modeled equations are firstly non-dimensionalized and then solved with the aid of Runge–Kutta fourth order together with the shooting method in order to guess the initial conditions.FindingsNumerical results are analyzed and presented in the form of tables and graphs. This study reveals that the temperature of the fin is decreasing as the wet porous parameter increases (m2) and the temperature for 10% concentration of nanoparticles are higher than 5 and 1%. Physical parameters involved in the study are analyzed and processed through RSM. It is come to know that sensitivity of temperature gradient to radiative parameter (Nr) and convective parameter (Nc) is positive and negative to dimensionless ambient temperature (θa). Furthermore, after ANN training it can be argued that the established model can efficiently be used to predict the temperature gradient over a radial porous fin for the copper-water nanofluid flow.Originality/valueTo the best of our knowledge, only a few attempts have been made to analyze the thermal behavior of radial porous fin surrounded by copper-based nanofluid under the influence of radiation and convection.