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Using substances of high latent heat such as phase change materials is a perfect technique in the energy storage units. Additionally, examining the heat transport and melting process for these materials is beneficial for a wide variety of solar-related applications. Therefore, this study aims to examine the time-dependent fractional melting process within inclined containers filled with Nanoparticles-enhanced Phase-Change Materials (NePCM) via the model of the enthalpy-porosity. The used NePCM is octadecane and the fractional derivatives are considered for all the time-dependent variables, namely, velocities, temperature and liquid fraction. The Caputo definition is applied to estimate the non-integer derivatives and the fractional order takes the values between 0.75 and 0.95. The solution methodology is depending on the Finite Volume technique with SIMPLE approach. The range of the Fourier number is between 0.05 and 0.4 and the resulting data is presented in terms of melting interface, liquid fraction, streamlines, isotherms and heat transfer rate. The main findings revealed that the influences of order of the fractional derivatives more significant at the higher values of the Fourier number and the melting interface points move towards the heated wall as order of the fractional derivatives is reduced. Also, at higher values of the fractional derivative's order (0.9), the maximizing of inclination angle causes a diminishing in the rate of the heat transfer. [ABSTRACT FROM AUTHOR]

This paper adopts the incompressible smoothed particle hydrodynamics (ISPH) method for simulating the dual diffusion of nano-encapsulated phase change material (NEPCM) in an annulus. Here, the novelty is appearing in simulating the double diffusion of NEPCM within a novel complex shape composed from the paradigm of an annulus between two circular cylinders mounted on rectangles. The ISPH method solved the regulating equations of a physical problem. The scales of parameters are a fusion temperature θ f (0.05 ≤ θ f ≤ 0.95) , buoyancy ratio 0 ≤ N ≤ 10 , nanoparticle parameter 0.01 ≤ φ ≤ 0.05 , a radius of a circular cylinder 0.1 ≤ r c ≤ 0.4 , Darcy parameter 10 - 2 ≤ D a ≤ 10 - 5 , and Rayleigh's number 10 3 ≤ R a ≤ 10 6 . The performed simulations showed that the different boundary conditions amongst an inner blockage and outer cavity walls are affecting the strength of concentration and temperature. The location of a phase change zone is varied according to the variations of variable boundary conditions and fusion temperature. The mean Nusselt and Sherwood numbers are improving under an enlargement in a radius of an internal circular cylinder, and Rayleigh numbers. [ABSTRACT FROM AUTHOR]

The flow and heat transfer fields of a nanofluid within V-shaped cavity are analyzed using the incompressible smoothed particle hydrodynamic (ISPH) scheme. Novel studies on a nanofluid-occupied V-shaped cavity with a partial layer heterogeneous porous medium were conducted. The bottom and top corners of the V-shaped enclosure have isothermal conditions while the remaining boundaries are considered adiabatic. Lengths of the heated and cold parts are assumed to be variables. The flow domain is filled with a partial layer porous medium. Three levels of the porous medium are taken into account, namely, horizontal heterogeneous, vertical heterogeneous and homogeneous porous media. Impacts of the wide ranges of the hot–cold partitions lengths L p (0.2 ≤ L p ≤ 1.5) , the nanoparticles volume fraction (0 % ≤ ϕ ≤ 5 %) , the Darcy number ( 10 - 2 ≤ D a ≤ 10 - 5 ) and the Rayleigh number ( 10 3 ≤ R a ≤ 10 5) on the features of the temperature and nanofluid flow are examined. The main outcomes disclosed that the average Nusselt number takes its maximum in case of the horizontal heterogeneous porous medium while the homogeneous porous medium case gives the lowest rate of the heat transfer. Therefore, for V-shaped cavity, the horizontal heterogeneous porous medium considers the best case of porous media. An augmentation on Rayleigh number rises the buoyancy force and accordingly the convective transport is enhanced. Further, the convective flow is enhanced as the hot–cold partitions lengths increase, regardless the porous case. [ABSTRACT FROM AUTHOR]

• The current study intends to talk about the unsteady Williamson hybrid nanofluid flow with heat transport across a stretching surface comprising the magnetic hydrodynamic, thermal radiative, suction/injection, and convective boundary condition effects respectively. • It has been demonstrated that the nanoparticle combination of zinc oxide and molybdenum disulfide Z n O - M O S 2 is superior in terms of enhancing heat transport. • To accomplish this goal, the modeled expressions are transmitted into dimensionless ODE by making use of several highly established transformations. • The aim of the numerical result of the current exploration is studied through Keller Box Analysis (KBA). Tabular data and statistical bar plots are used to compare this strategy. • The impact of physical variables such as Magnetic field parameter γ , Williamson fluid variable W e , Porous media β , Thermal radiation R d , Biot number B i and Prandtl number P r are analyzed through plots and tables. The current study intends to talk about the unsteady Williamson hybrid nanofluid flow with heat transport across a stretching surface comprising the magnetic hydrodynamic, thermal radiative, suction/injection, and convective boundary condition effects respectively. The study focused on the hybrid Williamson nanofluid, comprising of an EG ethylene glycol (C 2 H 6 O 2) and two types of nano-solid particles, c zinc oxide and molybdenum disulphide Z n O - M O S 2 . To accomplish this goal, the modelled expressions are transmitted into dimensionless ODE by making use of several highly established transformations. The aim of the numerical result of the current exploration is studied through Keller Box Analysis (KBA). Tabular data and statistical bar plots are used to compare this strategy. The impact of physical variables such as Magnetic field parameter γ , Williamson fluid variable W e , Porous media β , Thermal radiation R d , Biot number B i and Prandtl number P r are analyzed through plots and tables. An augmentation in the strength of the magnetic field and Williamson fluid parameter results in a reduction in velocity. However, a temperature rise is observed for higher values of the Williamson fluid parameter and magnetic parameters. The surface friction drag is diminished by the Forchheimer and Weissenberg values. The rate of mass transfer is strongly positively correlated with both the Schmidt number and chemical reaction. The present study has a remarkable agreement with the results that were previously published, which confirms the application and validation of the Keller-Box scheme. [ABSTRACT FROM AUTHOR]

Numerical emulations are conducted to study the physical situation of a variable properties nanofluid inside enclosures with rough boundaries. Two cases are considered based on way of the heating in the enclosures, namely, case1 the enclosure is heated from inside using two heated and cross-section ellipsis at the center of the enclosure and case2 in which differentially heated enclosures are assumed. The numerical procedure which applied to solve the non-homogenous Buongiorno mathematical model is based on the control volume technique with SIMPLE algorithm. Wide ranges for the temperature differences, roughness parameter and Darcy number are considered and the dynamic viscosity of CuO nanofluid is expressed as a mathematical form of the temperature and nanoparticle volume fraction based on experimental results. The main results revealed that the average Nusselt is enhanced by 11% in case 1 and by 30% in case 2 when the temperature differences are increased by 10 °C. Also, the decrease in Darcy number causes that rate of the heat transfer is reduced regardless way of the heating. Moreover the increase in the roughness parameter reduces the maximum values of the stream function in all cases. [ABSTRACT FROM AUTHOR]

This study aims to use incompressible version of smoothed particle hydrodynamics (ISPH) method for simulating natural convection flow of hot sloshing baffle inside a ferrofluid-filled cavity including the motion of cold circular cylinder. ISPH method is developed by using kernel renormalization function for the boundary treatment. The solid vertical baffle is carrying a hot temperature T h and it is sloshing inside a cavity under a resonance sway excitation. The motion of solid circular cylinder is treated as a rigid body motion by ISPH method. The horizontal cavity walls are adiabatic and both of vertical cavity walls and inner circular cylinder have a cool temperature T c . The source of the external variable magnetic field is positioned near to the middle of the left cavity wall. The partial governing equations with adjacent boundaries and rigid body motion were solved numerically using ISPH method. The control physical parameters are a wave amplitude A , baffle height H b , nanoparticle parameter ϕ and magnetic field parameter M f. The results reveal that the active zone and rigid body movement inside a cavity are affected by the hot vertical baffle parameters. The amplitude and baffle height promote the fluid circulation to enhance the heat transfer inside a cavity. The average Nusselt number on both of hot vertical baffle and left cavity wall decreases as the amplitude A increases from 0.1 to 0.3 and it increases as the vertical baffle height increases. Adding nanoparticles concentration augments the ferrofluid viscosity and then the strength of the ferrofluid flow is reduced. [ABSTRACT FROM AUTHOR]

• An inclined magnetic field has various applications in science and technology such as magnetic resonance imaging (MRI), particles accelerators, magnetic levitation (Maglev), magnetic recording technologies, magnetometers and compasses, etc. • After conducting extensive literature research, the authors expressed a strong desire to scrutinize the bioconvection flow of Casson nanoliquid with gyrotactic microorganisms and dual stratifications in an inclined magnetic field. • Using an inclined magnetic field, we will investigate the effect of bioconvection flow of Casson nanofluids on motile gyrotactic microorganisms. The base liquid is taken as blood while magnesium nanoparticles are drops in base fluid to make mixture of nanofluid. Casson nanofluid have gained significant attention in recent years due to their unique rheological; properties and potential applications in science and technology such as heat transfer enhancement, biomedical applications, microfluidics, oil and gas industry, and electronics. This study examines the gyrotactic bioconvection flow of Casson nanofluid across a bidirectional linear stretching sheet with the effects of inclined magnetic field. We examine the impact of velocity, temperature, solute, and microorganism slip on the flow of Casson nanoliquid over a bi-directional linear stretching sheet. Blood is considered as base liquid while magnesium nanoparticles are suspended in base liquid to make homogenous mixture of nanofluid. Also, Brownian and thermophoresis phenomena are taken in the model. Thermal, solutal and microorganism's stratifications are taken along with thermal and solutal slip conditions. The nonlinear partial differential equations are transformed into ordinary differential equations utilizing the proper similarity transformations. The solution of the flow model is acquired through Homotopic analysis method. Graphical discussions are provided for the effects of various embedded parameters include in fluid model. Some well-known findings have been identified as specific examples of the current investigation. Graphs are used to show how physical factors affect the nanofluid flow. It can be seen that when the magnetic factor, volume fraction parameter, and mixed convection parameter increase, the fluid velocities decreases. On the other hand, the buoyancy ratio factor and Rayleigh number cause to enhance the velocity outline. Temperature outline improves with the enhancement of volume fraction parameter and thermal slip factor. Concentration outline decelerates with the accelerating estimations of solutal slip and stratification parameters. Peclet number reduces the microorganism's profile. [ABSTRACT FROM AUTHOR]

Energy is essential for a nation's economic growth. Energy is recognized in contemporary society as being crucial to the development of quality of life and sustainability. The environment transforms/absorbs heat and sunlight in a variety of ways. Some of these transitions lead to the flow of renewable energy sources like wind and biomass. Solar energy has become one of the promising alternative energy sources in the future because to the improvements made to enhance its performance. In this context, the impact of solar radiation on modified nanofluid flow over an exponential stretching sheet is examined. Using the proper similarity transformations, the governing equations for the flow assumptions are reduced to ordinary differential equations. The numerical simulation of these simplified equations is then performed using the Runge-Kutta Fehlberg method and the shooting methodology. With the aid of graphs and tables, the effects of numerous parameters on the involved fields are described. Results reveal that the modified nano liquid shows increased heat transport for opposing flow situation than the assisting flow situation for incremented values of porosity parameter and volume fraction. The modified nanoliquid shows increased heat transport for opposing flow situation with respect to augmented values of radiation parameter. [ABSTRACT FROM AUTHOR]

Heat transfer enhancement is a contemporary challenge in a variety of fields such as electronics, heat exchangers, bio and chemical reactors, etc. Nanofluids, as innovative heat transfer fluids, have the potential to be an efficient tool for increasing energy transport. This benefit is obtained as a result of an enhancement in effective thermal conductivity and an alteration in the dynamics of fluid flow. Thus, this paper is concerned with heat transfer enhancement via nanofluids. The intention is to find numerical double solutions to the 3D stagnation-point flow (SPF) and heat transfer incorporated nanoparticles in a porous medium with generalized slip impacts. Appropriate similarity variables are used to non-dimensionalize the leading equations, which are then numerically solved using the three-stage Lobatto IIIa integration formula. The impacts of different parameters on the dynamics of flow and characteristics of heat transfer induced by nanofluids in the presence of an unsteady parameter, nanoparticle volume fraction, velocity slip parameter, and porosity parameter are investigated. Based on the latest findings, it is closed that the velocity slip improves the heat transfer as well as shear stress in the axial direction in both solutions, while the shear stress behaves oppositely in the respective lateral direction. In addition, the velocity profile remarkably enriches for both branch solutions, while the temperature distribution elevates for the upper branch and declines for the lower branch owing to the larger porosity parameter. [ABSTRACT FROM AUTHOR]

The double-diffusive natural convection in an enclosure filled with nanofluid is studied using ISPH method. The model used for the nanofluid incorporates the effects of Brownian motion and thermophoresis. In addition the thermal energy equations include regular diffusion and cross-diffusion terms. In ISPH algorithm, a semi implicit velocity correction procedure is utilized and the pressure is implicitly evaluated by solving pressure Poisson equation. The results are presented with flow configurations, isotherms, concentration and nanoparticle volume fraction contours and average Nusselt and Sherwood numbers for different cases. The results from this investigation are well validated and have favorable comparisons with previously published results. It is found that, among all cases, a good natural convection can be obtained by considering the double diffusive case. An increase in Soret number accompanied by a decrease in Dufour number results in an increase in average Nusselt number and a decrease in average Sherwood number. [ABSTRACT FROM AUTHOR]

A number of scientists have indicated interest in the promising area of research that involves improving heat transmission by utilizing nanoparticles. The dynamic properties of nanofluids reflect several applications in the cooling process, thermal engineering, heat exchangers, magnetic cell separation, energy production, hyperthermia, etc. In light of the appealing implications of nanofluids, the current research aims to explore the melting process of MHD hybrid AA7072 and AA7075 alloy nanoparticles from a movable cylinder. It also incorporates the irregular Thompson and Troian slip effect to simulate the intricate features of the nanofluid flow. The primary nonlinear partial differential equations (NPDEs) are converted into nonlinear ordinary differential equations (NODEs) with the use of the similarity technique. These converted equations are unraveled numerically via applying the built-in program bvp4c in MATLAB. It is visually examined that physical parameters affect the temperature and skin friction. The outcomes suggest that double solutions are found in a certain range of movable cylinder parameter. In addition, the skin friction is decelerated due to the critical shear rate and velocity slip factors while it is enhanced with the influence of suction and nanoparticles volume fraction. Moreover, the temperature is uplifted due to nanoparticles volume fraction and is declined due to Stefan number. In case of quanitative descriptions, the skin friction boosted up by almost 3.64% and 1.18% for the particular upper and lower branch outcomes due to the superior influences of nanoparticle volume fraction. Also, the skin friction decelerated for the branch of upper and lower solutions at about 5.26% and 22.55%, respectively, due to the larger velocity slip parameter. [ABSTRACT FROM AUTHOR]

This paper aims to analyze the second law of the thermodynamic for the non-Newtonian power-law nanofluids flow between inclined polygonal/polygonal or polygonal/cylinder shapes. Multi-wall carbon nanotubes are incorporated in the ethylene glycol as a base fluid to formulate the worked suspension. Electromagnetic forces together with the thermal radiation are taken into account. Unusually, the magnetic field is assumed to be horizontal while the flow domain is inclined and a semi implicit treatment is presented for the magnetic terms. The solution methodology is depending on the Galerkin finite element method (FEM) and the Characteristic-Based Split (CBS) scheme. Various designs for the considered models are considered based on the areas and shapes of the inner polygonal/cylinder. The main outcomes revealed that area of the flow and power-law index N control in the convective and heat transfer process. Also, the fluid friction irreversibility takes its maximum values at high values of the power-law index. Furthermore, ratios of the increase in values of the entropy tools (S T + , S F + , S tot +) due to the variations of γ take their maximum at γ = 30 and low values of Ha. [ABSTRACT FROM AUTHOR]