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A boiling surface with different initial roughness and under various nanoparticles volume fractions was studied in present work.

Develop a correlation and sensitivity analysis.

The results showed that for small (7.3 nm) and much larger (about 2,000 nm) surface roughness, compared to nanoparticle size of around 25 nm, the heat transfer rate of nanofluid diminishes relative to that of base fluid. The results also demonstrated that the boiling heat transfer rate is reduced by increasing the concentration of nanoparticles. For larger boiling surface roughness (480 nm) and nanoparticles volume fractions of less than 0.1 Vol.%, the value of heat transfer increases with the increase of nanoparticles concentration; and for those of more than 0.1 Vol.%, heat transfer rate decreases by adding more nanoparticles, significantly.

Finally, an equation was presented for estimating the wall superheat and the C_sf coefficient in terms of mentioned parameters.

The purpose of this paper is to investigate the momentum, heat and mass transfer characteristics of magnetic-nanofluid flow past a vertical plate embedded in a porous medium filled with ferrous nanoparticles. The analysis is carried out in the presence of pertinent physical parameters such as aligned magnetic field, thermal radiation, chemical reaction, radiation absorption, heat source/sink.

The flow governing PDEs are transformed into ODEs using appropriate conversions. Further, the set of ODEs is solved analytically using the perturbation technique. The flow quantities such as velocity, thermal and concentration fields are discussed under the influence of above-mentioned pertinent physical parameters with the assistance of graphical depictions. Moreover, the friction factor, local Nusselt and Sherwood number are discussed in tabular form.

The results indicate that flow and thermal transport phenomenon is more effective in the case of the aligned magnetic field as compared with the transverse magnetic field. Also, the nanoparticle volume fraction plays a vital role in controlling the wall friction and heat transfer performance. The validation of the obtained results is done by comparing them with the results of various numerical techniques, and hence found them in excellent agreement.

In present days, the external magnetic fields are very effective to set the thermal and physical properties of magnetic-nanofluids and regulate the flow and heat transfer characteristics. The strength of the applied magnetic field affects the thermal conductivity of magnetic-nanofluids and makes it aeolotropic. With this incentive, the authors investigated the flow and heat transfer characteristics of electrically conducting magnetic-nanofluids over a vertical surface embedded in a porous medium. The authors discussed the dual nature of ferrous-water nanofluid in the presence of aligned magnetic field and transverse magnetic field cases. The influence of several physical parameters on velocity, thermal and concentration field converses with the succour of graphs.

Hybrid nanofluids are of significant engrossment for their considerable heat transport rate. The steady flow of an incompressible viscous electrically conducted hybrid nanofluid is considered over a rotating disk under a magnetic field. Titanium oxide (TiO₂) and ferrous (CoFe₂O₄) nanoparticles are used with their physical properties and water is considered as host liquid. The purpose of this paper is to analyze how hydrothermal integrity varies for hybrid nanosuspension over a spinning disk in the presence of magnetic orientation.

Governing equations with boundary conditions are transformed by similarity transformations and then solved numerically with RK-4 method. A comparison of linear and nonlinear thermal radiation for the above-mentioned parameters is taken and the efficiency of nonlinear radiation is established, the same over nanofluid and hybrid nanofluid is also discussed. Heat lines are observed and discussed for various parameters like magnetic field, concentration, suction and injection parameter, radiation effect and Prandtl number.

Suction and increasing nanoparticle concentration foster the radial and cross-radial velocities, whereas magnetization and injection confirm the reverse trend. The rate of increment of radial friction is quite higher for the usual nanosuspension. The calculated data demonstrate that the rate for hybrid nanofluid is 8.97 percent, whereas for nanofluid it is 15.06 percent. Double-particle suspension amplifies the thermal efficiency than that of a single particle. Magnetic and radiation parameters aid the heat transfer, but nanoparticle concentration and suction explore the opposite syndrome. The magnetic parameter increases the heat transport at 36.58 and 42.71 percent for nonlinear radiation and hybrid nanosuspension, respectively.

Nonlinear radiation gives a higher heat transport rate and for the radiation parameter it is almost double. This result is very significant for comparison between linear and nonlinear radiation. Heat lines may be observed by taking different nanoparticle materials to get some diverse result. Hydrothermal study of such hybrid liquid is noteworthy because outcomes of this study will aid nanoscience and nanotechnology in an efficient way.

This paper aims to examine the thermal transmission and entropy generation of hybrid nanofluid filled containers with solid body inside. The solid body is seen as being both isothermal and capable of producing heat. A time-dependent non-linear partial differential equation is used to represent the transfer of heat through a solid body. The current study’s objective is to investigate the key properties of nanoparticles, external forces and particular attention paid to the impact of hybrid nanoparticles on entropy formation. This investigation is useful for researchers studying in the area of cavity flows to know features of the flow structures and nature of hybrid nanofluid characteristics. In addition, a detailed entropy generation analysis has been performed to highlight possible regimes with minimal entropy generation rates. Hybrid nanofluid has been proven to have useful qualities, making it an attractive coolant for an electrical device. The findings would help scientists and engineers better understand how to analyse convective heat transmission and how to forecast better heat transfer rates in cutting-edge technological systems used in industries such as heat transportation, power generation, chemical production and passive cooling systems for electronic devices.

Thermal transmission and entropy generation of hybrid nanofluid are analysed within the enclosure. The domain of interest is a square chamber of size L, including a square solid block. The solid body is considered to be isothermal and generating heat. The flow driven by temperature gradient in the cavity is two-dimensional. The governing equations, formulated in dimensionless primitive variables with corresponding initial and boundary conditions, are worked out by using the finite volume technique with the SIMPLE algorithm on a uniformly staggered mesh. QUICK and central difference schemes were used to handle convective and diffusive elements. In-house code is developed using FORTRAN programming to visualize the isotherms, streamlines, heatlines and entropy contours, which are handled by Tecplot software. The influence of nanoparticles volume fraction, heat generation factor, external magnetic forces and an irreversibility ratio on energy transport and flow patterns is examined.

The results show that the hybrid nanoparticles concentration augments the thermal transmission and the entropy production increases also while the augmentation of temperature difference results in a diminution of entropy production. Finally, magnetic force has the significant impact on heat transfer, isotherms, streamlines and entropy. It has been observed that the external magnetic force plays a good role in thermal regulations.

Hybrid nanofluid is a desirable coolant for an electrical device. Various nanoparticles and their combinations can be analysed. Ferro-copper hybrid nanofluid considered with the help of prevailing literature review. The research would benefit scientists and engineers by improving their comprehension of how to analyses convective heat transmission and forecast more accurate heat transfer rates in various fields.

Due to its helpful characteristics, ferrous-copper hybrid nanofluid is a desirable coolant for an electrical device. The research would benefit scientists and engineers by improving their comprehension of how to analyse convective heat transmission and forecast more accurate heat transfer rates in cutting-edge technological systems used in sectors like thermal transportation, cooling systems for electronic devices, etc.

Entropy generation is used for an evaluation of the system’s performance, which is an indicator of optimal design. Hence, in recent times, it does a good engineering sense to draw attention to irreversibility under magnetic force, and it has an indispensable impact on investigation of electronic devices.

An efficient numerical technique has been developed to solve this problem. The originality of this work is to analyse convective energy transport and entropy generation in a chamber with internal block, which is capable of maintaining heat and producing heat. Effects of irreversibility ratio are scrutinized for the first time. Analysis of convective heat transfer and entropy production in an enclosure with internal isothermal/heat generating blocks gives the way to predict enhanced heat transfer rate and avoid the failure of advanced technical systems in industrial sectors.

The purpose of this paper is to report the effects of radiation absorption and buoyancy forces on the boundary layer analysis of Casson nanofluid past a vertical plate in a porous enclosure filled with Al₅₀Cu₅₀ alloy nanoparticles.

The authors reconstructed the controlling equations as a group of nonlinear ODEs and solved analytically using perturbation technique. The vital interest in this analysis is to examine the influence of sundry physical parameters on the common profiles (velocity, temperature and concentration) conferred through the plots. Tabular values are listed to discuss the skin friction factor, heat and mass transfer rates. Dual solutions are observed for Newtonian and non-Newtonian fluid cases.

Acquired results indicate that the Casson fluid plays a major role in controlling heat and mass transfer rates as compared with Newtonian fluid. Also, raise in volume fraction of nanoparticles regulates the thermal fields, discerns the velocity fields. The authors established the comparison of present results with previously published results and they are found in good agreement for limited cases.

Because of the substantial properties of aluminium and its alloys such as, extreme corrosion resistance, exalted electrical and thermal conductivities and ease of fabrication they achieved tremendous applications in transportation especially in space and aircrafts, in the production of electrical transmission lines. In view of these, the current literature is perpetrated to probe the impact of radiation absorption and buoyancy forces on the heat and mass transfer analysis of Casson nanofluid in the presence of Al₅₀Cu₅₀ alloy nanoparticles.

According to the previous research, bioconvection has been recognized as an important mechanism in current engineering and environmental systems. For example, researchers exploit this mechanism in modern green bioengineering to develop environmentally friendly fuels, fuel cells and photosynthetic microorganisms. This study aims to analyse how this type of convection affects the flow behaviour and heat transfer performance of mixed convection stagnation point flow in alumina-copper/water hybrid nanofluid. Also, the impact of a modified magnetic field on the boundary layer flow is considered.

By applying appropriate transformations, the multivariable differential equations are transformed into a specific sort of ordinary differential equations. Using the bvp4c procedure, the adjusted mathematical model is revealed. Once sufficient assumptions are provided, multiple solutions are able to be produced.

The skin friction coefficient is declined when the nanoparticle concentration is increased in the opposing flow. In contrast, the inclusion of aligned angles displays an upward trend in heat transfer performance. The presence of several solutions is established, which simply leads to a stability analysis, hence verifies the viability of the initial solution.

The current findings are unique and novel for the investigation of mixed bioconvection flow towards a vertical flat plate in a base fluid with the presence of hybrid nanoparticles.

The purpose of this paper is to conduct a theoretical study on steady fully developed non-linear natural convection and mass transfer flow past an infinite vertical moving porous plate with chemical reaction and thermal diffusion effect. Closed-form expressions for dimensionless velocity, concentration, Sherwood number and skin-friction are obtained by solving the present mathematical model.

The fully developed steady non-linear natural convection and mass transfer flow near a vertical moving porous plate with chemical reaction and thermal diffusion effect is investigated. The non-linear density variation and Soret effect were taken into consideration. The dimensionless velocity, temperature and concentration profiles were obtained in terms of exponential functions, and were used to compute the governing parameters, skin-friction and Sherwood number.

The effect of coefficient of the non-linear density variation with the temperature (NDT) and concentration (NDC) parameter, chemical reaction parameter, thermal diffusion parameter are discussed with the aid of line graphs and tables. The analysis of the result shows that the velocity as well as skin-friction having higher values in the case of non-linear variation of density with temperature and concentration in comparison to linear variation of density with temperature and concentration. It is observed that the velocity and skin-friction increase with an increase in the Soret parameter.

The aim of this paper is to extend the work of Muthucumaraswamy (2002) by incorporating the thermal diffusion (Soret) effect and non-linear density variation with temperature (NDT) and concentration (NDC), on which, to the best knowledge of the authors, no studies have been carried out.

The purpose of this paper is to theoretically investigate the boundary layer nature of magnetohydrodynamic nanofluid flow past a vertical expanding surface in a rotating geometry with viscous dissipation, thermal radiation, Soret effect and chemical reaction.

The self-similarity variables are deliberated to transmute the elementary governing equations. The analytical perturbation technique is used to elaborate the united nonlinear ODEs.

To check the disparity on the boundary layer nature, the authors measured two nanofluids, namely, Cu-water and Cu-Kerosene based nanofluids. It is found that the Cu-water is effectively enhancing the thermal conductivity of the flow when compared with the Cu-kerosene.

Till now no analytical studies are reported on heat transfer enhancement of the rotating nanofluid flow by considering two different base fluids.

The purpose of this paper is to focus on the removal of copper(II) ions from aqueous model salt solution by using chitosan-coated magnetite nanoparticles.

The chitosan-coated magnetite nanoparticles were characterized using X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and thermogravimetric differential thermal analysis. The adsorption of Cu(II) by using magnetite nanoparticles as an adsorbent was investigated under different adsorption conditions. The parameters studied were contact time, adsorbent dose and initial concentrations.

The sorption capacities of prepared samples were studied for the removal of Cu²⁺ ions from aqueous model solutions with varying experimental conditions of the initial metal concentration, contact time and dosage. It is found that the removal percent of Cu²⁺ ions increases with an increase in initial metal concentration, contact time and amount of dosage.

Based on the obtained results, this study recommends that chitosan-coated magnetite nanoparticles can also be applied for removal of some heavy metal ions and/or organic compounds in aqueous solution. It is recommended that this study be shared with the polymer-based nanomaterial researchers, especially material science.

The purpose of this paper is synthesis of oil-soluble non-spherical nanoparticles modified with free phosphorus and sulphur modifier and investigation of their tribological properties as environment-friendly lubricating oil additives.

To study the effect of morphology of nanoparticles on their tribological properties, rice-like CuO nanoparticles were synthesized. To improve the solubility of CuO nanoparticles in organic media, the in-situ surface modification method was used to synthesize these products. The morphology, composition and structure of as-synthesized CuO nanoparticles were investigated by means of transmission electron microscopy, X-ray powder diffraction, thermogravimetric analysis and Fourier transform infrared spectrometry. The tribological properties of as-synthesized CuO nanoparticles as an additive in liquid paraffin (LP) were evaluated with a four-ball tribometer. The morphology and elemental composition of worn steel ball surfaces were analysed by X-ray photoelectron spectroscopy.

It has been found that as-synthesized CuO nanoparticles with rice-like morphology have an average size of 7 and 15 nm along the shorter axle and longer axle, respectively, and can be well-dispersed in LP. Tribological properties evaluation results show that as-synthesized CuO nanoparticles as additives in LP show good friction-reducing, anti-wear and load-carrying capacities, especially under a higher normal load.

Oil-soluble rice-like CuO nanoparticles without phosphorus and sulphur were synthesized and their tribological properties as lubricating oil additives were also investigated in this paper. These results could be very helpful for application of CuO nanoparticles as environment-friendly lubricating oil additives, owing to their free phosphorus and sulphur elements characteristics.