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The aim is to study the effects of fin conductivity ratio, Darcy number, and Rayleigh number on the average Nusselt number for fins made of porous material when attached to the inner cylinder of the annulus between two concentric cylinders. The paper also aims to compare the results with those obtained using solid fins over a range of Rayleigh numbers.

The Darcy‐Brinkman equations were used to model the fluid flow inside the porous media and the Boussinesq approximation was used to model the buoyancy effect. The energy equation is also solved to find the temperature distribution in the domain of interest. The model equations are solved numerically using a finite volume code.

Porous fins provided higher heat transfer rates than solid fins for similar configurations. This enhancement in heat transfer reached 75 per cent at Ra=5 × 10⁴ and Da=2.5 × 10⁻². It is also found that unlike solid fins the rate of heat transfer from the cylinder equipped with porous fins decreases with increasing the fin inclination angle.

The range of the Rayleigh number considered in this research covers only the laminar regime. The research does not cover turbulent flows. In addition to that, the local thermal equilibrium assumption is used.

This work can help designers in selecting the proper material properties and operating conditions in designing porous fins to enhance the heat transfer in the annulus between two horizontal concentric cylinders under natural convection condition.

This work has not been done before and it can initiate additional research projects as looking at the performance of porous fins under other conditions and configurations (e.g. turbulent conditions).

In this paper, temperature distribution and fin efficiency in a moving porous fin have been discussed. The heat transfer equation is formulated by using Darcy's model. Heat transfer coefficient and thermal conductivity vary with temperature. The surface emissivity of the fin varies with temperature as well as with wavelength. Thermal conductivity is taken as a linear and quadratic form of temperature. The entire analysis of the paper is presented in non-dimensional form.

In this study, a new mathematical model is investigated. The novelty of this model is surface emissivity which is considered temperature and wavelength dependent. Another interesting point is the addition of porous material. The Legendre wavelet collocation method has been used to solve the nonlinear heat transfer equation. Numerical simulations are carried out in MATLAB software.

An attempt has been made to discuss temperature distribution in the presence of porosity and wavelength-temperature-dependent surface emissivity. The effect of various parameters on temperature has been discussed, including thermal conductivity, emissivity, convection-radiation, Peclet number, sink temperature, exponent “n” and porosity. Fin efficiency is also calculated for some parameters. According to the study, heat transfer rate increases with higher radiation-convection, emissivity, wavelength and porosity parameters.

The numerical results are carried out by using the Legendre wavelet collocation method, which has been compared with exact results in a particular case and found to be in good agreement. The percent error is calculated to find the error between the current method and the exact result. A comparison of the obtained results with the previous data is presented to validate the numerical results.

The aim of the text is to present a historical foundation of the changing conceptualization of citizenship and to outline the present trends in citizenship theory from a social and educational perspective. Based on a 132literature review from the 1990s and the first decade of the new millennium, an attempt is made to describe possible changes in school curricula in order to demonstrate the diversifying content and role of civic education. These considerations must be placed in a broader context of the transforming content of current public debates on citizenship and nationhood, including the increasingly ethnicity-oriented views of nationhood in many European and non-European countries, accompanied by the rise of anti-immigrant discourse.

The purpose of this study is to target the solution of nonlinear porous fin problem. In contrast to the various complicated numerical or analytical approximate procedures existing in the literature used to approximate the temperature field over a porous fin, this study outlines a direct method based on series expansion of the temperature in the vicinity of the mounted surface, eventually requiring no numerical treatment at all to resolve the temperature field.

This study uses a direct method based on series expansion of the temperature in the vicinity of the mounted surface, eventually requiring no numerical treatment at all to resolve the temperature field.

Explicit closed-form formulae for the fin tip temperature as well as for the heat transfer rate, hence for the fin efficiency, which are functions of the porosity parameter and Biot number, are provided. The thresholds and the convergence regions regarding the physical parameters of the resulting approximations are easy to determine from the residual formula.

The novelty of the method is that the accuracy of the solution is controllable and can be gained up to any significant digit of desire by increasing the number of terms in the series solution.

The purpose of this paper is to study the thermal behaviour of a fully wet porous fin of longitudinal profile. The significance of radiative and convective heat transfer has been scrutinised along with the simultaneous variation of surface emissivity, heat transfer coefficient and thermal conductivity with temperature. The emissivity of the surface and the thermal conductivity are considered as linear functions of the local temperature between fin and the ambient. Darcy’s model was considered to formulate the heat transfer equation. According to this, the porous fin permits the flow to penetrate through it and solid–fluid interaction occurs.

Runge–Kutta–Fehlberg fourth–fifth-order method has been used to solve the reduced non-dimensionalized ordinary differential equation involving highly nonlinear terms.

The impact of pertinent parameters, such as convective parameter, radiative parameter, conductivity parameter, emissivity parameter, wet porous parameter, etc., on the temperature profiles were elaborated mathematically with the plotted graphs. The heat transfer from the fin enhances with the rise in convective parameter.

The wet nature of the fin enhances heat transfer and in many practical applications the parameters, such as thermal conductivity, heat transfer coefficient as well as surface emissivity, vary with temperature. Hence, the main objective of the current study is to depict the significance of simultaneous variation in surface emissivity, heat transfer coefficient and thermal conductivity with respect to temperature under natural convection and radiation condition in a totally wetted longitudinal porous fin.

The purpose of this study is to peruse natural convection in a CuO-water nanofluid-filled complex-shaped enclosure under the influence of a uniform magnetic field by using control volume finite element method.

Governing equations formulated in dimensionless stream function, vorticity and temperature variables using the single-phase nanofluid model with the Koo–Kleinstreuer–Li correlation for the effective dynamic viscosity and the effective thermal conductivity have been solved numerically by control volume finite element method.

Effects of various pertinent parameters such as Rayleigh number, Hartmann number, volume fraction of nanofluid and shape factor of nanoparticle on the convective heat transfer characteristics are analysed. It was observed that local and average heat transfer rates increase for higher value of Rayleigh number and lower value of Hartmann number. Among various nanoparticle shapes, platelets were found to be best in terms of heat transfer performance. The amount of average Nusselt number reductions was found to be different when nanofluids with different solid particle volume fractions were considered due to thermal and electrical conductivity enhancement of fluid with nanoparticle addition.

A comprehensive study of the natural convection in a CuO-water nanofluid-filled complex-shaped enclosure under the influence of a uniform magnetic field by using control volume finite element method is addressed.

The purpose of this paper is to study the thermal behaviour of radial porous fin wetted with nanofluid containing different shaped nanoparticles in the presence of natural convection and radiation. Here, the nanofluid suspended with molybdenum disulfide nanoparticle with base fluid as water is considered. The influence of non-spherical nanoparticles such as platelet, cylinder, brick and blade shapes is also investigated.

The modeled equations are non-dimensionalized and solved numerically via Runge–Kutta–Fehlberg method combined with shooting scheme.

The flow natures of the pertinent parameter are represented graphically and discussed their physical significance. From the validation of obtained outcome, it is found that the use nanofluid has significant influence on heat transfer rate. Among platelet, cylinder, brick and blade shapes, brick-shaped nanoparticle shows better heat transfer rate.

The present paper deals with an analysis of the flow of molybdenum disulfide nanoparticles suspended in water over a porous fin of a radial profile. The effect of differently shaped nanoparticles on the heat transfer enhancement through the radial porous fin is investigated for the first time. The natural convection and radiation effects are also considered. The modeled equations are non-dimensionalized and solved numerically via Runge–Kutta–Fehlberg method combined with shooting scheme. The effect of pertinent parameters on temperature field is examined. From the validation of obtained outcome it is found that the use nanofluid has significant influence on heat transfer rate. Among platelet, cylinder, brick and blade shapes, brick-shaped nanoparticle shows better heat transfer rate.

The purpose of this study is to conduct a numerical computation to analyse the thermal attribute and heat transfer phenomenon of a fully wetted porous fin of a longitudinal profile. The fin considered is that of a functionally graded material (FGM). Based on the spatial dependency of thermal conductivity, three cases such as linear, quadratic and exponential FGMs are analysed.

The governing equations are nondimensionalised and solved by applying Runge-Kutta-Fehlberg fourth-fifth order technique.

The parametric investigation is executed to access the significance of the pertinent parameters on the thermal feature of the fin and heat transmit rate. The outcomes are portrayed in a graphical form.

No such study has yet been published in the literature.

Studying the effect of localized wall discharge on the fluid flow and heat transfer for a flow over backward facing step is the main purpose of this paper. Jet is used to control the reattachment length which controls the fluid flow and heat transfer downstream the step. Several parameters are to be investigated: geometric; expansion ratio, location of the jet, and jet angle flow; Reynolds number, jet velocity.

Numerical simulation using both the standard K−ε and renormalized group turbulence theory (RNG) K−ε models are used to model flow in the computational domain. The energy equation is also used to model the heat transfer characteristics of the flow. The model equations are solved numerically using a finite volume code.

It is found that the presence of the wall jet at a proper location can significantly influence the flow and heat characteristics of the problem. Furthermore, varying the ratio of the jet velocity to the main stream velocity could play an important role in controlling the size of the circulating bubble and, therefore, the fluid and heat transfer characteristics of the flow, whereas, the expansion ratio has less influence. It is also found that increasing Reynolds number increases the value of maximum heat transfer but has less influence on either its location or the reattachment length.

The range of the Reynolds number considered in this research covers only the turbulent regime. The research does not cover laminar flows. The results and conclusions cover only three values of expansion ratios. Namely (expansion ratio (ER)=1.67, 1.8 and 2). Conclusions should not be read beyond these values of ER.

This work gives designers of similar flows a new method of controlling the fluid flow and heat transfer by varying jet angle.

This work has not been done before and it can initiate additional research projects as investigating the effect of applying wall jets in combustors.

This chapter provides a context for other case-study chapters in this volume that explore in more depth steps taken to provide a decolonised perspective in the history curriculum. The chapter first provides a brief overview of developments in recent years towards diversifying the history curriculum. It then focuses specifically on two surveys conducted by the Historical Association in 2019 and 2021, examining how history teachers have responded to more recent calls both to diversify and (from some) to decolonise the curriculum. As the surveys only provide self-reported data about any changes made (rather than allowing direct observation of teachers’ practice), it is not possible to determine whether a genuinely decolonised approach is being adopted. There are, nonetheless, clear indications that small but significant steps are being taken in many school contexts to diversify curriculum content, seeking to address both an overwhelming Anglo-centric bias and a narrow conception of what constitutes ‘British history’.