Heat Transmission Rate Research Articles

Optimum thermal design for heat and mass transfer of non-Newtonian liquid within converging conduit with thermal jump and zero-mass flux

The performance of heat transfer materials is strongly dependent on physical characteristics such as viscosity, thermal conductivity, and density. Among these, evolving thermal conductivity is a critical element in fluid heat transmission. In general, the poor thermal conductivity of industrial fluids is a significant barrier for heat transfer properties. The problem, however, has been revealed with the emergence of nanoparticles generated by various materials. This effort aims to demonstrate the mass and heat transfer attributes of the Carreau nanofluid through non-parallel channel with zero mass flux and variable thermal conductivity. The Buongiorno nanofluid model introduces the dual diffusion phenomena of nanomaterial. The analysis are carried out after reduction of governing ODE's into first order. The reduced equations are tickled numerically with Rung-Kutta method. The findings demonstrate that the thermal source, Brownian motion and thermal conductivity parameters exhibits a linear ascent on temperature profile, whereas effect of Prandtl number Pr is conflicting. The mass transfer rate is impacted negatively by the mass diffusivity value. The existence of the variables thermal conductivity factor ∈1 and mass diffusivity ∈2 leads to an elevated rate of heat and mass transmission. In the current investigation, a comparison is made for heat and mass transfer performance.

Thermophoretic particle deposition on double-diffusive Ree-Eyring fluid flow across two deformable rotating disks with Hall current and Ion slip

This work emphasizes the characteristics of thermophoretic particle deposition on Ree-Eyring fluid flow with Hall current and Ion slip effects between two deformable spinning disks. The novelty of the envisioned model is strengthened by considering generalized Fourier and Fick laws with thermal source/sink. The proposed model is optimized by taking multiple slip boundary constraints at the surface. The equations that govern the flow are simplified with the use of the proper transformations. The numerical solution is obtained using the boundary value problem of fourth order (bvp4c) method. Graphical representations of the emerging parameters are presented. Numerical values of skin friction coefficient, local Nusselt, and Stanton number are highlighted in tabular form. The velocity field depicts a deteriorating behavior on incrementing the Reynold number. For augmented values of Hall and ion slip parameters fluid velocity elevates. An upsurge is noticed in the axial and radial velocities on amplifying the rotation parameter. On augmenting the thermophoretic parameter the particle deposition at the interface of the upper disk diminishes. Growing values of rotation parameter, Weissenberg, and Reynold numbers imply an additional resistance to the fluid flow that ultimately reinforced the surface drag force causing a decline in the fluid velocity. The rate of heat transmission accelerates on enhancing the Reynold number, however, heat flux exhibits a decay on augmenting the thermal slip parameter. On augmenting the thermophoretic parameter particle deposition deteriorates at the interface of the upper disk. An excellent concordance is noticed when the outcomes are contrasted with the previous literature. For the value of the rotation parameter β=-1 and β=-8 the percentage error of the present analysis with Imtiaz et al. [68] are 0.00001 and 0.00002.

Impact of thermal radiations, heat generation/absorption and porosity on MHD nanofluid flow towards an inclined stretching surface: Non‐similar analysis

AbstractObjective of this investigation is to provide a novel study of the flow of a magnetohydrodynamics (MHD) nanofluid over an inclined stretching surface in a permeable medium in a 2‐dimensional boundary layer. The convection model further incorporates heat radiation and heat sources/sinks. Nanomaterials include magnesium oxide and copper oxide . Using non‐similarity transformations, the set of governing equations is transformed into a set of dimensionless partial differential equations (PDEs). Using the local non‐similarity technique, the resulting system of dimensionless PDEs is treated as a set of ordinary differential equations (ODEs), and then solved with the help of the bvp4c MATLAB tools. This comprehensive research involves a thorough investigation of the significant starting physical characteristics and their impacts on the velocity and nanofluid temperature profiles. These profiles are shown using a set of graphical representations and numerical tables. It is worth noting that changes in the magnetic and porosity parameters result in a decrease in the velocity profile, but the Grashof number exhibits a reciprocal correlation. When we account for the effects of the Eckert number and the radiation parameters in a given flow regime, we also see an increase in the nanofluid's temperature profile. It has been shown that when the magnetic number and the Eckert number are augmented, the heat transmission rate decreases. The skin friction coefficient grows on a logarithmic scale when magnetic parameters and nanoparticle concentration are increased in estimation. The numerical calculations are checked for accuracy by comparing them to previously published findings, which guarantees an exact match in a constrained setting. Scientists investigating nanomaterials and their applications in manufacturing and thermal engineering may find this research instructive.

Bioconvection effects on the heat and mass transfer of unsteady MHD blood flow over a permeable artery

The mathematical analysis of blood’s non-Newtonian behavior in the presence of drug nanoparticles and microbes with magnetic and thermal radiation effects is the focus of the current article. The response surface methodology (RSM) is used to conduct a sensitivity study of the bioconvection impacts on the heat and mass transmission rate of the unsteady magnetohydrodynamic blood flow. The physical laws governing unsteady blood flow over stretching blood vessels are mathematically represented as a system of partial differential equations, which are numerically solved using the Fourth Order Runge–Kutta Method in conjunction with the Shooting Technique. Following an analysis of the numerical data, statistical conclusions are drawn on the heat and mass transfer rates. The impact of Brownian motion and thermophoresis factors is discovered to increase blood temperature. Additionally, at the largest Brownian motion factor and maximum thermophoresis effect, the largest heat transfer rate occurs. It is also observed that the lowest mass transfer rates are generated by higher radiation parameter and chemical reaction parameter values. The findings of the study show potential for important applications in therapeutic hypothermia, magnetic therapy, and targeted drug delivery.

Comparative investigations of Ag/H2O nanofluid and Ag-CuO/H2O hybrid nanofluid with Darcy-Forchheimer flow over a curved surface

Abstract Nanofluid performed well and produced good results in heat transport phenomena, attracting scientists to suspend other combinations of nanoparticles, called “hybrid nanofluid. Hybrid nanofluids are superior than nanofluids due to their thermal capabilities and emerging benefits that contribute to the boost in the rate of heat transmission. Applications for these nanoparticles, including sophisticated lubricants, are increasing in the fields of bioengineering and electricity. The main prospective of this research is to inquire about the water-based dual nature nanofluid stream numerical simulation through the irregular stretched sheet with heat transfer. In this perspective, silver with base fluid water is used as nanoparticles for nanofluid, and for making hybrid nanofluid, copper oxide and silver particles are used with water-based fluid. Modified Fourier and Fick’s model for heat flux utilized the above phenomenon and observed the heat and mass transport. Similarity variables are needed to transform the partial differential equations into associated nonlinear ordinary differential equations, which are then computationally resolved by the technique of bvp4c which is a built-in function in MATLAB mathematical software. Based on the concurrent approximations, reformations are performed to determine the impact of various quantities on flow variables. The predicted outcomes are depicted in velocity, temperature, and concentration profiles through graphical depiction. The factors indicate that the hybrid nanofluid is more powerful in the transfer of heat than a basic nanofluid because of its superior thermal characteristics. The velocity profile decays for the increasing values of Darcy-Forchheimer parameter. The thermal profile increases for the higher magnitude of Darcy-Forchheimer parameter. The velocity distribution profile increases for the higher values of curvature parameter, while the thermal profile decreases. This unique work might benefit nanotechnology and related nanocomponents. This safe size-controlled biosynthesis of Ag and CuO nanoparticles has resulted in a low-cost nanotechnology that may be used in a variety of applications. Biosynthesized Ag and CuO particles have been used successfully in a variety of applications, including biomedical, antibacterial agents, biological, food safety, and biosensing, to mention a few.

Physical and mathematical investigation of natural convection and Fourier flux on the flow of energy and diffusion transmission of a body of cone and a cylinder revolution

The thermal radiation and Fourier flux have drawn the attention of scientists and experts due to their extensive applications in the fields of medicine, manufacturing modern airplanes, water distillation, more efficient electronic devices, more efficient batteries, radiating treatment, and the textile industry. Through careful consideration of this, the mathematical investigation of natural convection and Fourier flux on the flow of energy and diffusion transmission of a body of cone and cylinder revolution, located in a saturated medium, has been described for the dual situations (flow over a cone and a cylinder). After then, the Runge–Kutta technique was used to explain the leading mechanism. Possessions of governing physical measures of local Nusselt and Sherwood numbers as well as velocity, thermal and diffusion figures are provided with support of tables and diagrams. It is motivating to declare that mass transfer rate is advanced in cone kind of revolution matched to cylinder kind of revolution with rising [Formula: see text]. Also, the heat transmission rate is upper in cylinder revolution equated to cone revolution.

Thermal analysis of magnetized [formula omitted] nanolubricant flow in a Darcy-Forchheimer porous medium with nonlinear heat generation

The nanolubricant ZnO−SAE50 is widely used in automobiles and heat exchange systems to minimize friction and resist corrosion and scrape between moving parts. It also improves system's performance and durability and cuts fuel consumption. In this work, the flow of magnetized ZnO−SAE50 nanolubricant is analyzed over a flat plate with variable temperature immersed in a Darcy-Forchheimer medium. The thermal analysis is carried out in the occurrence of nonlinear heat generation and thermal radiation. Furthermore, the influences of viscous dissipation and Joule heating have also been deliberated. A micro-nano convection model named as Patel model of thermal conductivity has been used in view of rise in thermal conductivity. The governing PDEs are altered to ODEs with the incorporation of similarity transformations and then numerically treated by using an eminent MATLAB's built-in bvp4c method. The influences of different physical parameters on velocity, temperature and Nusselt number are discussed and analyzed graphically and in tabular form. The velocity profile diminishes under the impacts of inertia coefficient and magnetic field. The temperature and exponential dependent heat generation parameters considerably enhance temperature of the nanolubricant ZnO−SAE50. The temperature power coefficient tends to reduce the temperature profile. The enhancing strength of thermal radiations and nonlinear heat generation significantly enhance the value of Nusselt number. Furthermore, an increase in the value of temperature dependent heat generation parameter from 0.2 to 0.6 tends 12.37% increment in the value of Nusselt number in conventional SAE50oil, whereas the nanolubricant ZnO−SAE50 experiences a more significant 26.72% increment in the value of Nusselt number. Thus, better heat transmission rate can be achieved by using ZnO−SAE50 nanolubricant rather than conventional SAE50 oil.

Compound passive heat transfer augmentation techniques: A comprehensive review

AbstractThe function of energy is becoming increasingly vital in meeting the requirements of modern societies and sustaining rapid economic and industrial growth globally. Heat transfer equipment has been employed for heat recovery and conversion in various domestic and industrial applications. Therefore, due to the recent global energy crisis, boosting the thermal efficiency of energy systems has become an essential requirement, which would reduce both their size and rates of energy demand. There are active and passive methods for boosting heat transfer rates. As they have no moving components, passive methods are more affordable and dependable than active ones. Applying two or more passive techniques concurrently will result in a higher heat transmission rate than any approach working independently. The current article comprehensively reviews experimental and computational investigations of passive compound forced convection heat transfer augmentation techniques at laminar, transition, and turbulent flow regimes. This article focuses on compound techniques arrangement in the form of turbulators, typical twisted tapes (TTs), surface roughness, vortex generators, and so on. The pioneering research suggests that using a lower twist ratio, lower pitch, and smaller winglet angles in TTs can result in higher heat transfer rates, albeit with a slightly increased friction factor. The combination of alternate‐axes and wings in TTs leads to more effective heat transfer enhancement within the tube.

Peristaltic transport of radiative and dissipative MHD third order nanofluid through the vertical asymmetric channel with heat and mass convection

: The fundamental purpose of the present study is to provide a novel framework for investigating the peristaltic flow through a vertical asymmetric channel filled with a magnetic third order nanofluid model saturated in a porous medium under the influence of varying electrical conductivity. The essential characteristics of Brownian and thermophoresis phenomena are additionally included in the modelling of the heat equation, in besides joule heating, viscous dissipation, heat generation/absorption, and nonlinear thermal radiation. Furthermore, the effects of double diffusion convection are examined, with a small Reynolds number along with extended wavelength examples that reflect biological scientific assumptions are used. The software Mathematica's built-in command ND Solve is implemented to solve the derived nonlinear ordinary differential equations system numerically. One of the most significant phenomena concerning peristaltic motion, known as the trapping phenomenon, has also been spotlighted using contour plots and circulating bolus. The key discoveries showed that the size of the trapping bolus tends to decrease while the density of trapping bolus increases with an enhancement in the temperature- and concentration-dependent electrical conductivity coefficient. Further, for all areas under consideration, the rate of heat and mass transmission is enhanced due to an augmentation in the coefficient of temperature-dependent electrical conductivity.

Computation of inclined magnetic field, thermophoresis and Brownian motion effects on mixed convective electroconductive nanofluid flow in a rectangular porous enclosure with adiabatic walls and hot slits

This analysis theoretically investigates the transport phenomena of mixed convection flows in an enclosure of rectangular geometry saturated with a permeable medium filled with an electrically conducting nanofluid. An inclined magnetic field is taken into consideration. Buongiorno’s model is utilized to characterize the nanoliquid. The enclosure has adiabatic walls and hot slits. A uniform cold temperature is maintained at the enclosure’s lower and upper walls. The enclosure’s vertical walls are thermally insulated with hot slits at the center of the walls. This kind of analysis on mixed convective, electrically conducting nanofluid flows in enclosures finds applications in smart nanomaterial processing systems and hybrid electromagnetic nanoliquid fuel cells. The Marker-And-Cell (MAC) method is utilized to solve the transformed nondimension system of governing equations subject to the fitted boundary conditions. The effects of key physical parameters on streamlines, isotherms, iso-concentration contour plots and the heat transmission rate are examined. The simulations demonstrate that the Richardson number has a predominant impact on the thermo-solutal features of nanofluid flow in the rectangular enclosure. Variations in magnetic field and buoyancy ratio parameters exert a notable influence on the iso-concentrations and isotherms. An increase in the Darcy number values exhibits a tendency to magnify the local heat transfer rate. Higher Grashof number values reduce the local Nusselt number profiles. The effect of porous parameter is significant in the streamlines, isotherms and iso-concentrations. Thus, the porous medium can significantly control the transport phenomena in the enclosure. The concentration, temperature and velocity contours are strongly modified by the variations in the Grashof number.

Flow and heat transfer analysis of Couette and Poiseuille flow of a hybrid nanofluid with temperature-dependent viscosity and thermal conductivity

The purpose of this research is to quantify the influence of a number of independent parameters (−0.5≤α1,β1,β2≤0.5) on the heat transmission rate and the temperature of a nanofluid hybrid flowing between parallel plates. The linked nonlinear momentum and energy equations are solved using the regular perturbation method for two different cases resembling the plane Couette flow and Poiseuille flow. By combining engine oil with multiwalled carbon nanotubes (MWCNT) and aluminum oxide nanoparticles, a hybrid nanofluid is produced with wide-ranging lubricating and industrial applications. It has been found that the hybrid nanofluid can function as a coolant provided the relevant parameters are adjusted appropriately. It is demonstrated that these additives have a tendency to stabilise the thermal and the volume flow rate, hence decreasing randomization that is necessary for a good lubricant to function. The findings of the study indicate that β1 has a greater influence on temperature, while β2 has a stronger effect on velocity. In addition to the variable model, the results for the constant model have also been deduced, and the novel study demonstrates that the considered variable viscosity model tends to produce a more uniform temperature distribution.

Comparative analysis to study the Darcy–Forchheimer Tangent hyperbolic flow towards cylindrical surface using artificial neural network: An application to Parabolic Trough Solar Collector

Solar thermal collectors convert sunlight into useful thermal energy by absorbing its incoming radiation. Concentrated solar power technologies use the parabolic trough solar collector to collect solar energy with temperatures ranging from 325–700 K. The tangent hyperbolic fluid model is one of the most important non-Newtonian fluid models. Laboratory studies demonstrate that this model accurately predicts the shear thinning phenomenon. In addition, tangent hyperbolic fluid has a better heat transfer performance due to its rheological bearing at various shear rates. The current study investigates the heat transmission performance of Darcy–Forchheimer tangent hyperbolic radiative inclined cylindrical film movement in parabolic trough solar collector with an irregular heat sink/source utilizing the Levenberg–Marquardt technique and backpropagated neural networks. Through the implementation of required transformations, this system is turned into an equivalent nonlinear ordinary differential system. The findings are investigated for Newtonian and tangent hyperbolic fluid cases to understand the rheological characteristics. The outcomes are considered using graphical and mathematical evaluations. Fluids featuring tangent hyperbolic rheological conductivity are obligatory for active rate of heat diffusion. As a consequence, these fluids may be employed in Parabolic Trough Solar Collector for increased heat transmission rate and operational usage of solar energy. Furthermore, We create a dataset using the Runge–Kutta fourth-order shooting technique to create the proposed multilayer perceptron artificial neural network. The data points representing the MoD values are observed to be closely clustered around the zero deviation line. Additionally, it is important to highlight that these data points have relatively small numerical values. Moreover, when calculating the average MoD values for each output, it becomes evident that they are consistently very low.

Thermal performance of radiated annular extended surface using advanced nanomaterials influenced by various physical controlling parameters for nucleate boiling case

ApplicationsThe fins are extended surfaces around different objects to enhance their thermal transmission from the object to the surrounding environment. These are significant for electronics cooling, car radiator, heat exchanging devices, compressors and electric motor etc. Purpose and methodologyThe main concerns of this study are to analyze the heating/cooling performance of annular fin for nucleate boiling case. In Pool boiling, the boiling occurs in the absence of bulk movement of the fluid. In such situation, the fluid remains stationery and the motion occurs under natural convection. For significant outcomes, the effects of magnetic field, thermal radiation, nanomaterials and heating species added during the modeling. Then, the energy model of the second order is obtained and analyzed via numerical scheme. Core findingsThe results over the domain of interest revealed that the heat transmission from the fin to the environment can be enlarged by strengthening the coefficient of thermal conductivity and α2 in the range of 0.1,0.3,0.5,0.7. The concentration φ3 from 2% to 8% dominantly boost the fin performance; however, φ1 has weaker effects. Further, directed radiations (Rd = 0.1,0.3,0.5,0.7) rays control the heat performance and insertion of heating source (Q1 = 0.2,0.4,0.6,0.8) is one of the reliable way to enhance the heat transmission rate in the surrounding environment.

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.

Magnetized casson SA-hybrid nanofluid flow over a permeable moving surface with thermal radiation and Joule heating effect

Here in, heat transfer characteristics of a magnetized Casson sodium alginate-alumina/copper hybrid nanofluid flowing through the permeable moving plane are investigated considering the effects of thermal radiation and Joule heating with Tiwari and Das model. The primary objective of the present study is to investigate the influence of the velocity ratio parameter on the solid volume fraction and the Casson parameter. In addition, the velocity and temperature profiles used in the current study illustrate the effects of the velocity ratio parameter R, solid volume fraction, suction effect, magnetic field, Joule heating, and thermal radiation. To apply the three-stage Lobatto IIIa with boundary value problems (bvp4c) approach to implement the appropriate similarity variables to transform the partial differential equations (PDEs) into a system of nonlinear ordinary differential equations (ODEs). It has been determined that there are two branch solutions for the velocity ratio parameter against using the Casson parameter and copper volume fraction values. Non-unique branch at R < Rci however, no branch happens at R > Rci. As the Eckert number and radiation grew, the rate of heat transmission surged. The increase of Casson hybrid nanofluid parameter values caused to drop the skin friction in both upper and lower branch.

Empirical study for Nusselt number optimization for the flow using ANOVA and Taguchi method

ANOVA and Taguchi is an optimization tool used to find the optimal combination to achieve the highest heat transmission rate for a Casson-Carreau nanofluid flow over a curved surface. Exponentially generating heat, thermal radiation, Joule heating, chemical reaction along with velocity slip, and Stefan blowing peripheral conditions are employed for the current investigation. The rate of heat and mass transmission has been analyzed using the Cattaneo-Christov duplexed diffusion model. Entropy synthesis in the fluid flow system is also planned for the research. The graphs of solutions to the topic under consideration have been compiled by a tool called the Runge-Kutta-Fehlberg scheme. According to the outcomes of the present study, when thermal and solutal relaxation parameters are increased, the corresponding thermal and solutal profiles decrease. Both the speed and concentration panels benefit from the Stefan blowing parameter. The Nusselt number falls when Eckert number and Prandtl number increase. When the velocity slip factor is enhanced, the velocity has slowed down, while a rise in the second-order velocity slip factor encourages the same. The Taguchi optimization method has disclosed that the highest signal-to-noise ratio is attained when the magnetic parameter is 0.7, the thermophoresis parameter is 0.05, the Prandtl number is 7, the Eckert number is 0.06, and the thermal relaxation parameter is 0.05. Thus, the maximum heat transfer rate obtained is 2.75354. The thermophoresis parameter has a huge contribution of about 93.83%, whereas the thermal relaxation parameter has the least contribution, i.e., 0.03%, on heat transport rate.

Sustainable Energy Progress via Integration of Thermal Energy Storage and Other Performance Enhancement Strategies in FPCs: A Synergistic Review

Flat plate collectors (FPCs) are the leading solar thermal technology for low-medium range temperature applications. However, their expansion in developing countries is still lacking because of their poor thermal performance. Improving the thermal performance of flat plate collectors (FPCs) is a crucial concern addressed in this review This study comprehensively discussed the performance improvement methods of FPCs, such as design modification, reflectors, working fluid, and energy storage materials, by covering current issues and future recommendations. Design factors such as coating and glass cover thickness, thickness of absorber plate and material, air gap between the glass cover and absorber plate, and riser spacing, along with insulation materials, are examined for their impact on FPC performance. Absorber design changes with selective coatings for improving the heat transmission rate between the working fluid and absorber are critical for enhancing collectors’ thermal output. The nanofluids utilization improved FPC’s thermal performance in terms of energetic and exergetic outcomes in the 20–30% range. Moreover, adding a heat storage unit extends the operating hours and thermal output fluctuations of FPCs. Research suggests that employing turbulators and nanofluids as heat transfer fluids are particularly effective for enhancing heat transfer in FPCs. This comprehensive review serves as a critical tool for evaluating and comparing various heat transfer augmentation techniques, aiding in the selection of the most suitable option.

Analysis of mixed convective-radiative heat transfer in a porous square cavity filled with various nanofluids

The present study examines the numerical simulation of mixed convective fluid movement and heat transference within the square cavity with various nanofluids. In this work, the nanofluids are prepared by suspending zinc oxide (ZnO)/silicon dioxide nanoparticles into water /kerosene /ethylene glycol base liquids. Features of various nanofluids flow inside cavity are investigated and this kind of studies may be useful in automobile applications and electrical gadgets. The vertical walls of the cavity are hot, the bottom wall is partially cooled, and the top wall is considered to be adiabatic. The Marker-And-Cell (MAC) method is utilized to solve the governing non-dimensional partial differential equations. The impact of heat generation/absorption (Q), nanoparticle volume fraction Darcy number (Da), Richardson number (Ri), Reynolds number (Re), and the thermal radiation parameter (Rd) are scrutinized. The outcomes are displayed informs of streamlines, isotherms, and local and average Nusselt numbers. The comparative study is performed and it finds a good accordance with the literature. As fluid flow and heat transfer are concerned, ZnO-Ethylene Glycol(EG) nanofluid explores the optimum features among the considered nanofluids. When 5% ZnO/SiO 2 nanoparticles are suspended into water, compared to SiO 2-water nanofluid, ZnO-water nanofluid has more than 10.81% mean rate of heat transmission. Suspension of 5% ZnO in water/kerosene/EG has the tendency to enhance the mean heat transfer rates of water/kerosene/EG up to respectively. The highest mean heat transfer rate is attained when the cavity’s aspect ratio is fixed as 1:1.

Heat transfer analysis of magnetized Cu-Ag-H2O hybrid nanofluid radiative flow over a spinning disk when the exponential heat source and Hall current are substantial: Optimization and sensitivity analysis

The main motive of the instigated mathematical model is to observe the impact of Hall current on the hybrid nanofluid flow over a disk that is rotating. The copper and silver metal nanoparticles have been considered with volume fraction φ1=φ2=0.01(0.01)0.04 and are suspended in water to form the hybrid nanofluid. Diverse characteristics like magnetic field, thermal radiation, and (ESHS) exponential space dependent heat source are incorporated to investigate the nature of the flow. The present mathematical model is initiated with partial derivative equations (PDEs) which are redrafted as ordinary derivative equations (ODEs) with appropriate transformations of similarity. The results are attained through a blend of the Runge-Kutta method, shooting procedure, and the influences of parameters on the flow of nanofluid and hybrid nanofluid are compared and illustrated both as tables and graphs. The present numerical research is unique because by employing a complete quadratic CCD framework using the RSM strategy, the sensitivity and optimization analysis of the heat transmission improvement for the volume fraction, ESHS, and thermal radiation parameters have been performed. The R-squared and adjusted R-Squared are obtained as 100%. The residual graphs and contour diagrams of the same are also shown. The current study establishes that the Hall parameter increases the radial velocity, but it also controls the energy and cross-radial velocity. The rate of heat transmission is increased by thermal radiation even at low levels of ESHS. The rate of heat transmission is more sensitive (0.024670) to the volume fraction of the hybrid nanofluid when ESHS is at an intermediate level. The lowest sensitivity (-1.269967) value towards ESHS is observed For thermal radiation and ESHS parameter values, the heat transmission rate of the mono nanofluid is not as great as that of hybrid nanofluid. The current study finds applications in the generation of hydroelectric power, air cleansing and rotating equipment, healthcare devices, and many other industries.

Experimental and Numerical Investigations on the Heat Transfer of a Helical Coil Heat Exchanger Utilized α-Al2 O3 nanofluid

This study focused on investigating the impact of α-Al2O3 nanoparticles on heat transfer in shell and helical coiled tube heat exchangers. The objective was to analyze the influence of various geometrical characteristics, specifically the coil pitch, on the Nusselt numbers of both sides using a combination of numerical simulations and experimental methods. The working fluid for the hot side was water. The research encompassed an examination of the friction factor for three different coils, exploring the effects of pitch spacing on heat transfer, and assessing the influence of nanoparticles on heat transfer on the inner side of the coil. The findings of the current work indicated significant improvements in heat transfer parameters when employing water-α-Al2O3 nanoparticles as the cold fluid. Comparing this heat exchanger to one without the inclusion of α-Al2O3 nanoparticles revealed a remarkable efficiency enhancement of 7.68 percent. This increase strongly suggests a notable acceleration in the rate of heat transmission within the heat exchanger. Overall, this study provides valuable insights into the utilization of α-Al2O3 nanoparticles in enhancing heat transfer in shell and helical coiled tube heat exchangers. The results highlight the potential benefits of incorporating nanoparticles into such systems, leading to improved performance and more efficient heat exchange processes.