Search

In this study, natural laminar convection of Al 2 O 3 /water nanofluid in a cavity slightly different from shaped H was investigated using the monophasic model. The various parameters of this flow were determined numerically using CFD-Fluent software using the finite-volume method by introducing Boussinesq approximation. The analysis is carried out for three values of the Rayleigh number (10 5 ; 2.3 · 10 5 and 3.072 · 10 5) and for three values of the form factor defined for this enclosure (0.2; 0.3 and 0.4). The impact of Rayleigh number, nanofluid concentration and cavity form factor on dynamic and thermal structure of the flow was analyzed. The results are shown in form of streamlines, isotherms, and profiles of velocity, temperature, and Nusselt number. Nusselt number rises with increasing Rayleigh number and nanofluid concentration and decreases with the form factor of the cavity. This study is well developed relative to those carried out before. With using Al 2 O 3 nanofluid, the heat transfer is improved because its thermal conductivity is increased compared to that of the base fluid. Finally, to predict heat transfer inside cavity, correlations for the Nusselt number were proposed for each form factor of the cavity. These correlations are rarely presented in this type of study. [ABSTRACT FROM AUTHOR]

In this paper, a hybrid computational fluid dynamics technique is proposed to study turbulent flow and conjugate heat transfer patterns. A typical shaped room with a radiant heating panel is considered. The mesoscopic lattice Boltzmann method coupled with the finite difference solution of macroscopic energy equation is used to compute the thermal and flow fields. To describe the radiant flux distribution along the solid–fluid interfaces, the Lambert law is implemented. An in-house code written in MatLab is validated against direct numerical simulation data obtained for a Rayleigh number up to 1011. A computational study is conducted when varying the Rayleigh number, heat flux density, radiant panel length, physical properties of the enclosure and external heat transfer coefficients with constant walls thickness and the ambient temperature. It is found that the air temperature is decreased in the room as the Rayleigh number is raised. The panel length is found to drastically affect the thermal field. However, the flow structure is altered insignificantly. The stagnant zone of air is formed at the bottom corners with low values of heat fluxes. [ABSTRACT FROM AUTHOR]

The study investigates the approach to enhance the thermal management of battery cell module by attaching number of inverted triangular cavity to its casing. A sinusoidal heating is considered to battery cell module or a left wall of the cavity. The sinusoidal heated region is considered to be a function of amplitude ratio. The objective is to transfer the heat from module using natural convection process. The enhanced heat transfer is possible by adopting hybrid nanofluid in a triangular cavity due to its improved thermophysical properties. Thus, the investigation on natural convection heat transfer, fluid flow, and irreversibility within an inverted right-angled triangular porous cavity is conducted. Numerical results are obtained through an own-house FORTRAN coding, that uses the streamfunction–vorticity algorithm. The numerical results are derived for various values with Rayleigh number (103-106\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$${10}^{3}-{10}^{6}$$\end{document}), Darcy number (10-5-10-1)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$${10}^{-5}-{10}^{-1})$$\end{document}, Hartmann number (0-50)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$0-50)$$\end{document}, amplitude ratio (0.0-0.9\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$0.0-0.9$$\end{document}) and volume fraction of nanoparticles (0.01-0.04\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$0.01-0.04$$\end{document}), respectively. The irreversibility and flow results are compared with the various hybrid nanofluids. The study indicates that opting inverted right-angled triangular cavity rather than a square shape leads to an improvement in heat transfer. Accordingly, this inverted right-angled triangular cavity natural convective cooling can be considered as optimum design with the battery cell module for improved thermal management.Graphical abstract: The study investigates the approach to enhance the thermal management of battery cell module by attaching number of inverted triangular cavity to its casing. A sinusoidal heating is considered to battery cell module or a left wall of the cavity. The sinusoidal heated region is considered to be a function of amplitude ratio. The objective is to transfer the heat from module using natural convection process. The enhanced heat transfer is possible by adopting hybrid nanofluid in a triangular cavity due to its improved thermophysical properties. Thus, the investigation on natural convection heat transfer, fluid flow, and irreversibility within an inverted right-angled triangular porous cavity is conducted. Numerical results are obtained through an own-house FORTRAN coding, that uses the streamfunction–vorticity algorithm. The numerical results are derived for various values with Rayleigh number (103-106\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$${10}^{3}-{10}^{6}$$\end{document}), Darcy number (10-5-10-1)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$${10}^{-5}-{10}^{-1})$$\end{document}, Hartmann number (0-50)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$0-50)$$\end{document}, amplitude ratio (0.0-0.9\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$0.0-0.9$$\end{document}) and volume fraction of nanoparticles (0.01-0.04\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$0.01-0.04$$\end{document}), respectively. The irreversibility and flow results are compared with the various hybrid nanofluids. The study indicates that opting inverted right-angled triangular cavity rather than a square shape leads to an improvement in heat transfer. Accordingly, this inverted right-angled triangular cavity natural convective cooling can be considered as optimum design with the battery cell module for improved thermal management. [ABSTRACT FROM AUTHOR]

This paper examines the capability of hybrid lattice Boltzmann method to simulate developed turbulent buoyancy-driven flows in closed rectangular cavities. The two-relaxation time mesoscopic lattice Boltzmann method is used as a fluid dynamics solver, whereas the thermal behavior is described in terms of the macroscopic energy equation. Numerical simulation is performed for air-filled square and tall cavities in a range of the Rayleigh number 10 9 ≤ R a ≤ 10 11 . An in-house numerical code is developed in this study and successfully validated against up-to-date numerical and experimental data of other researches. It is found that the proposed hybrid approach accurately predicts the location of thermal plumes at the isothermal walls despite an insignificant error in the heat transfer rate with the R a ≥ 3 · 10 10 . [ABSTRACT FROM AUTHOR]

This paper examines the capability of hybrid lattice Boltzmann method to simulate developed turbulent buoyancy-driven flows in closed rectangular cavities. The two-relaxation time mesoscopic lattice Boltzmann method is used as a fluid dynamics solver, whereas the thermal behavior is described in terms of the macroscopic energy equation. Numerical simulation is performed for air-filled square and tall cavities in a range of the Rayleigh number 10 9 ≤ R a ≤ 10 11 . An in-house numerical code is developed in this study and successfully validated against up-to-date numerical and experimental data of other researches. It is found that the proposed hybrid approach accurately predicts the location of thermal plumes at the isothermal walls despite an insignificant error in the heat transfer rate with the R a ≥ 3 · 10 10 . [ABSTRACT FROM AUTHOR]

In this study, a theoretical analysis is performed to address the features of heat and mass transfer phenomena of two-dimensional viscous fluid flow of Oldroyd-B nanofluid over a vertical stretched sheet which contains gyrotactic microorganisms by considering the mixed convection and inclined magnetic field effects. The induced flow features have been considered by triple stratified medium. Additionally thermal radiation effect is included in the energy equation. To make the present study reasonably worthy, impact of Joule heating and heat sink/source is also considered. By applying the defined similarity transformations physical flow system is reduced to nonlinear system. Thereafter, numerical solution with desired accuracy is obtained with the help of RKF-45 method. Graphical representation is done for the flow controlling parameters involved in this analysis. Main observations of the present study are velocity distribution declined with a relaxation time and thermal stratification parameter and motile density profile is promoted by increasing bioconvection Rayleigh number and buoyancy ratio. These results are reasonable correlated with the previous findings reported in literature. Based on these scientific reports, this work is relevant to bio-inspired nanofluid-enhanced fuel cells and nanomaterials fabrication processes. [ABSTRACT FROM AUTHOR]

The current problem is performed to analyze the heatline visualization of the mixed convection mechanism and heat transfer in a double lid-driven square cavity having a heated wavy bottom surface. The moving vertical surfaces are under adiabatic conditions, and the top surface is at a cold temperature. The finite element method is employed to determine the dimensionless governing equations controlled by specific boundary conditions. The implications of the Reynolds number ( 10 ≤ Re ≤ 500 ), the directions of the constant moving wall ( λ l = ± 1 , λ r = ± 1 ), Richardson number ( 0.01 ≤ Ri ≤ 100 ), Prandtl number ( 0.015 ≤ Pr ≤ 10 ) and the number of oscillations ( 1 ≤ N ≤ 4 ) are visualized by the streamlines, isotherms and the heatlines. The same direction of lid-driven cases leads to two primary circulation cells. The Richardson number increases as it imposes the increment of the vertical temperature gradient. At a high Prandtl number, the convection mode of heat transfer is fully established, and heat conduction occurs at a low Prandtl number. Moreover, the number of oscillations has the most significant direct impact on the streamlines and the temperature distributions compared to the flat surface. Higher Reynolds and Prandtl numbers result in an increment in the local and average Nusselt numbers. The result shows that one oscillation of the wavy surface with a low Richardson number yields to have an optimum heat transfer in the cavity. [ABSTRACT FROM AUTHOR]

This paper aims to understand the characteristics of heat transfer and flow by natural convection of Al2O3–Cu/water-based hybrid nanofluid-filled square domain containing various configurations of a corrugated conducting solid under a horizontal magnetic field. The basic equations in their non-dimensional form are numerically solved using the finite volume discretization technique. The Corcione correlations are utilized to estimate the overall heat conductivity and overall viscosity of the hybrid nanoliquid when the nanoparticle's Brownian motion is taken into account. The dependency of different governing factors of the investigation, namely volume fraction of the combined nanoparticles, Rayleigh and Hartmann numbers, undulation number, undulation amplitude and the fluid/solid heat conductivity ratio, on thermohydrodynamic characteristics are delineated. Results stated that the maximum heat transmission rate was obtained for weak values of Hartmann, undulation number, undulation amplitude and high values of Rayleigh and nanoparticles volumic fraction. In addition, the fluid/solid heat conductivity ratio parameter was found to boost the heat transfer at weak Rayleigh while reducing it at high Rayleigh. [ABSTRACT FROM AUTHOR]

The purpose of the current study is to numerically investigate the effects of shape factors of nanoparticles on natural convection in a fluid-saturated porous annulus developed between the elliptical cylinder and square enclosure. A numerical method called the control volume-based finite element method is implemented for solving the governing equations. The modified flow and thermal structures and corresponding heat transfer features are investigated. Numerical outcomes reveal very good grid independency and excellent agreement with the existing studies. The obtained results convey that at a certain aspect ratio, an increment in Rayleigh and Darcy numbers significantly augments the heat transfer and average Nusselt number. Further, enhancement of Rayleigh number increases the velocity of nanofluid, while that of aspect ratio of the elliptical cylinder shows the opposite trend. [ABSTRACT FROM AUTHOR]

The aim of the current study is natural convection analysis conjugated with entropy generation analysis in an incinerator shaped permeable enclosure loaded with Al2O3–H2O nanofluid subjected to the magnetic field with a rectangular wavy heater block positioned on the bottom of the cavity wall. The bottom and top horizontal walls are adiabatic; the inclined and vertical walls are thought to be cooled. Firstly, the governing expressions and standard k–ε turbulence model are rewritten from dimensional form to non-dimensional form using dimensionless parameters such as vorticity and stream function. In the next step, the equation of entropy generation is written in dimensionless form. Then, the system of non-dimensional governing equations is solved by the finite volume method (FVM) conjugated with a non-dimensionalization scheme using ANSYS Fluent. Fine grids (wall y+ < 2) with inflated layers have been used for the higher Rayleigh number. The effects of the Rayleigh number in the laminar region (Ra = 103, 104, and 105) and turbulent region (Ra = 108, 0.5 × 109, and 109), Darcy number (Da = 0.01 and 100), Hartmann number (Ha = 0 and 40), and the nanoparticles ( ϕ = 2 % ) on the entropy generation number and natural convection are investigated. The validation results were in good agreement with those of the literature. The results demonstrate that for the laminar region, the Nusselt number and entropy generation number increase as the Rayleigh number and the Darcy number grow, whereas both of them abate as Hartmann number increases. In the turbulent region, the average Nusselt number decreases by ascending the Darcy number. Also, for turbulent region (Ra = 109), convection flow strength decreases 6.28% when Hartmann number increases from 0 to 40, whereas the entropy generation number increases 31.5% at Da = 0.01. [ABSTRACT FROM AUTHOR]

The main objective of this numerical investigation was to analyze the entropy generation and natural convection flow under magnetic field in a square enclosure filled with Cu–Al2O3/water hybrid nanofluid. The enclosure is equipped with a conducting hollow cylinder. The free convective flow in the enclosure is created by a horizontal temperature difference between the vertical left hot wall and the right cold wall under the Boussinesq approximation. The dimensionless equations of steady laminar natural convection flow for Newtonian and incompressible mixture are discretized using the finite volume method. The effective thermal conductivity and viscosity of the hybrid nanofluid are calculated using Corcione correlations taking into consideration the Brownian motion of nanoparticles. Numerical solutions were performed for different values of the nanoparticles volumic concentration, Hartmann number, Rayleigh number, radius ratio, and solid–fluid thermal conductivity ratio. The analyzed results show that inserting a hollow conducting cylinder plays an important role in controlling flow characteristic and heat transfer rate as well as irreversibilities within the cavity. [ABSTRACT FROM AUTHOR]

The conjugate natural convection of a new type of hybrid nanofluid (Ag–MgO/water hybrid nanofluid) inside a square cavity is addressed. A thick layer of conductive solid is considered over the hot wall. The governing partial differential equations (PDEs) representing the physical model of the natural convection of the hybrid nanofluid along with the boundary conditions are reported. The thermophysical properties of the nanofluid are directly calculated using experimental data. The governing PDEs are transformed into a dimensionless form and solved by the finite element method. The effect of the variation of key parameters, such as the volume fraction of nanoparticles, Rayleigh number, and the ratio between the thermal conductivity of the wall and the thermal conductivity of the hybrid nanofluid (Rk), is studied. Furthermore, the effects of the key parameters are investigated on the temperature distribution, local Nusselt number, and average Nusselt number. The results of this study show that the heat transfer rate increases by adding hybrid nanoparticles for a conduction-dominant regime (low Rayleigh number). The heat transfer rate is an increasing function of both the Rayleigh number and the thermal conductivity ratio (Rk). In the case of a convective-dominant flow (high Rayleigh number flow) and an excellent thermally conductive wall, the local Nusselt number at the surface of the conjugate wall decreases substantially by moving from the bottom of the cavity toward the top. [ABSTRACT FROM AUTHOR]

The aim of the current study is to investigate the natural convection heat transfer in a square enclosure with a wavy circular heater under magnetic field and nanoparticles. The governing equations that are expressed in dimensionless form are solved by means of control volume finite element method employing a validated FORTRAN code. The dimensionless controlling parameters of the present investigation are shape factor of nanoparticles (m), Hartmann number (Ha), Rayleigh number (Ra), and nanoparticle volume fraction (ϕ). In this study, the amplitude A and number of undulations N are fixed at a constant value of 0.2 and 8, respectively. The obtained results portray that in the presence of waves on the inner wall of the annulus, the heat transfer rate is an ascending function of Rayleigh number, nanoparticle volume fraction and less obvious function of their shape factor, while it is a descending function of the Hartmann number. [ABSTRACT FROM AUTHOR]

A numerical study is carried out on mixed convection and entropy generation of Al2O3/water nanofluid due to a rotating cylinder inside a square cavity. The numerical computations are performed taking the non-homogenous model of Buongiorno into consideration. The inner moving rotating circular cylinder is maintained at a constant hot temperature Th and the other left and right vertical walls of the cavity are maintained at a constant cold temperature Tc. The bottom and top horizontal walls are maintained as adiabatic. The Galerkin weighted residual method is implemented to numerically solve the governing equations. The Rayleigh number (104 ≤ Ra ≤ 107), angular rotational velocity (0 ≤Ω≤ 600) nanoparticles loading (0 ≤ ϕ ≤ 0.04) and the dimensionless radius of rotating cylinder (0.1 ≤ R ≤ 0.4) are the governing parameters of this study. Numerical results for the streamlines, isotherms, isentropic lines, nanoparticle loading, local and average Nusselt number and Bejan number are obtained and presented graphically. A detailed discussion of the results is performed to highlight the physics of the problem. [ABSTRACT FROM AUTHOR]

The study ahead deals with the natural convection of MWCN–Fe3O4/water magnetic hybrid nanofluid flowing in a porous medium. The flow domain is affected by an inclined magnetic field influencing the dynamic viscosity. The dependency of the flow and heat transfer characteristics on Rayleigh number, Ra = 103–106; Hartman number, Ha = 0–50; inclination angle of the magnetic field, ϕ = 0°–180°; magnetic number, δ0 = 0–2.0; porosity, ε = 0.1–0.9; Darcy number, Da = 10−7–10−1;and volume fraction of the composite nanoparticles, φ = 0, 0.1 and 0.3% is studied numerically. At low Rayleigh number Ra = 104, dispersing the nanocomposite particles increases the average Nusselt number Nuavg, while that decreases the Nuavg when Ra = 105 and 106. The dependency of viscosity on the magnetic field decreases the Nuavg at 0° < ϕ < 135°, which is due to an increase in overall viscosity of the nanofluid. After that (ϕ ≥ 135°), the average Nusselt number is greatly enhanced by increasing ϕ from 135° up to 180°. There is no meaningful change in average Nusselt number of the hybrid nanofluid by increasing the inclination angle of magnetic field in the absence of magnetic field-dependent viscosity (δ0 = 0). [ABSTRACT FROM AUTHOR]

The natural-convection thermal performance of a dielectric liquid in a cubical module triggered by a varying rectangular heat generation source is numerically examined. The rectangular generating source is connected to the center of one vertical wall of the cubical module, which is constructed either vertically or horizontally. Two vertical walls neighboring the source-mounted wall are kept cold, and the remaining walls are insulated from the environment. The isotherms and the velocity contours are computed for a wide range of the Rayleigh number as well as the generating-source aspect ratio and the thermal conductivity ratio, demonstrating the variations of the thermal and stream structures inside the module. It is established that the thermal performance is more significant and is an increasing function of the heat generating-source aspect ratio and the Rayleigh number for the two altered alignments of the generating source. According to the practical demands of the thermal management of electronic devices, the heat transfer rate can be magnified or diminished by choosing the proper parameters such as thermal conductivity ratio, Rayleigh number, the aspect ratio and orientation of the generating source. [ABSTRACT FROM AUTHOR]

The objective of the present study is to peruse the natural convection in the cavity containing inclined elliptical heater under shape factor of nanoparticles and magnetic field. The control volume-based finite element method is used for solving conservation equations. Numerical results show very good grid independency and very good compromise with other works. The result shows the heat transfer grows via mounting nanofluid volume fraction. The increment of Ra number also leads the heat transfer to ascend. Heat transfer of nanofluid with three different shapes of nanoparticles is studied, and results show the platelet nanoparticle is better than the other ones. The influence of magnetic field on heat transfer is also investigated and discussed. The obtained outcomes represent that at a certain Rayleigh number, the average Nusselt number descends with the ascendant of Hartmann number. Finally, the new correlation is reported for calculating the Nu number in these geometries. [ABSTRACT FROM AUTHOR]

This study provides numerical analysis of the free convection of copper-water-based nanofluid filling a triangular cavity with semicircular bottom wall. The cavity sidewalls are maintained at cold temperature, while the semicircular wall is maintained at hot temperature. The other wall segments are thermally insulated. To control the energy transport within the cavity, a uniform magnetic field is applied horizontally. The physical domain is discretized according to the control volume finite element method which has been used to solve the governing equations. The physical and geometrical aspects of the current problem are investigated by inspecting the impacts of Rayleigh number, Hartman number, aspect ratio and the volume fraction of the Cu nanoparticles. Decreasing the radius of the hot semicircle enlarges the average Nusselt number at the absence of the magnetic field. When the magnetic field is applied, this effect is conversed within Ra ≤ 104. This conversed impact does not hold up when Ra is raised to 105. The numerical results are correlated in a sophisticated correlation of the average Nusselt number with other parameters. [ABSTRACT FROM AUTHOR]

In this study, natural convection of CuO-water nanofluid in a square cavity with a conductive partition and a phase change material (PCM) attached to its vertical wall is numerically analyzed under the effect of an uniform inclined magnetic field by using finite element method. Effects of various pertinent parameters such as Rayleigh number (between 105 and 106), Hartmann number (between 0 and 100), magnetic inclination angle (between 0∘ and 90∘), PCM height (between 0.2H and 0.8H), PCM length (between 0.1H and 0.8H), thermal conductivity ratio (between 0.1 and 100) and solid nanoparticle volume fraction (between 0 and 0.04) on the fluid flow and thermal characteristics were numerically analyzed. It was observed that when magnetic field is imposed, more reduction in average Nusselt number for water is obtained as compared to nanofluid which is 31.81% for the nanofluid at the highest particle volume fraction. The average heat transfer augments with magnetic inclination angle, but it is less than 5%. When the height of the PCM is increased which is from 0.2H to 0.8H, local and average Nusselt number reduced which is 42.14%. However, the length of the PCM is not significant on the heat transfer enhancement. When the conductivity ratio of the PCM to the base fluid within the cavity is increased from 0.1 to 10, 29.5% of the average Nusselt number enhancement is achieved. [ABSTRACT FROM AUTHOR]

In this study, mixed convection and entropy generation in a nanofluid filled triangular cavity under the influence of rotating cylinder and flexible sidewall were numerically analyzed with finite element method. The inclined sidewall was cooled while the left vertical wall is partially heated. Heat transfer rate enhances as the values of Rayleigh number, angular rotational velocity of the cylinder, elastic modulus of the flexible sidewall and solid nanoparticles volume fraction increase. Nusselt number enhances more in the counter-clockwise direction of the cylinder as compared to clockwise directional rotation and 13.55% of average heat transfer enhancement was achieved for Ω=3000 when compared to motionless cylinder. Average Nusselt number increases by about 30.50% when the elastic modulus of the flexible wall is changed from 500 to 105. The changes in the velocity profiles are significant for the lower part of the triangular enclosure with respect to changes in angular rotational velocity and elastic modulus as compared to upper part of the cavity. Adding nanoparticles increases heat transfer especially for the lower part of the cavity and 49.63% of heat transfer enhancement was achieved for the highest volume fraction when compared to base fluid. Normalized total entropy generation rates enhance for higher values of elastic modulus of the flexible wall, angular rotational speed of the circular cylinder and nanoparticle volume fractions. [ABSTRACT FROM AUTHOR]