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AS in the case of end‐plate fins, inset fins have the effect of increasing the effective aspect ratio of the tail plane, but to a somewhat less extent. The tail with fins will be compared with an untwisted elliptical tail without fins, because this method of comparison is very clear and being also used to compare wings of different shapes is familiar to people concerned with aerodynamic problems.

The purpose of this paper is to investigate the effects of concavity level on performance parameters of a parabolic fin under the influences of natural convection and radiation.

Computational fluid dynamics software (FLUENT) is used for the heat transfer analysis. Optimum fin geometry is searched in order to maximize the heat dissipation from fin to the ambient while minimizing the volume of fin.

The fin profile with concavity level of 2 dissipates 14.92, 17.53, 24.33 and 26.60 percent more heat and uses 34.62, 49.64, 57.66 and 63.09 percent much material compared to the fin with concavity level of 4, 6, 8 and 10, respectively. It is also observed that the amount of heat dissipation per mass considerably increases with increasing concaveness.

The research was carried out for five different concavity levels in the range of 2-10.

The results can be used in passive cooling applications of PV systems. Also, heat sinks for CPU cooling can be redesigned with respect to the results obtained from the research.

In this paper, effects of concavity level on performance parameters of a parabolic fin are investigated for the first time. It is observed from the numerical results that the fin profile with higher concavity levels provides a cheaper and lighter heat dissipation device so it is recommended for the applications where the weight and the cost are primary considerations such as cooling of photovoltaics.

The aim of this work is to determine the optimal number and location of the fin(s) for maximum laminar forced convection heat transfer from a cylinder with multiple high conductivity radial fins on its outer surface in cross‐flow, i.e. Nusselt number, over a range of Reynolds numbers.

The effect of several combinations of number of fins, fin height, and fin(s) tangential location on the average Nusselt number was studied over the range of Reynolds numbers (5‐150). The problem was investigated numerically using finite difference method over a stretched grid. The optimal number and placement of the fins, for maximum Nusselt number, was determined for several combinations of Reynolds number and fin height. The percentage improvement in heat transfer per fin(s) unit length, i.e. cost‐efficiency, was also studied.

The results indicate that the fin(s) combination with the highest normalised Nusselt number is not necessarily the combination that results in the highest fin cost‐efficiency.

The results of the study can be used to design highly efficient cross‐flow forced convection heat transfer configurations from a horizontal cylinder with minimum cost.

This paper aims to present an elegant exact solution in terms of elementary functions for a special pin fin without the classical length-of-arc approximation.

The temperature distribution along the fin and the surface function, both being the functions of a shape parameter, is inversely proportional to each other. The specialty of the spine is such that its shape and temperature profile are linked for a given Biot number.

Exact formulas for the pin fin tip temperature, pin fin base heat transfer rate, surface area of the spine and thermal fin efficiency are also given.

Without the traditional arc length assumption, the pin fin is shown to be an effective extended surface to remove the excessive heat from the hot surface it is pinned to. Optimum pin fin dimensions leading to the maximum base heat transfer rate are also worked out for a specified fin volume.

In this paper three‐dimensional numerical simulations were conducted for the periodically developed laminar flow in the sinusoid wavy fin‐and‐tube heat exchanger.

A novel CLEARER algorithm is adopted to guarantee the fully coupling between the pressure and velocity, and it can not only speed up the convergence rate, but also overcome the severe grid non‐orthogonality in the wavy fin‐and‐tube heat exchanger. The influence of wave amplitude, fin pitch, tube diameter and wave density on fluid flow and heat transfer characteristics is analyzed under different Reynolds numbers.

The numerical results show that with the increase of wave amplitude, tube diameter or wave density, both the friction factor and Nusselt number will increase, and the increase rate of friction factor is higher than that of Nusselt number. It is interesting to note that, at low Reynolds numbers the Nusselt number increases with the decrease of fin pitch, while at high Reynolds numbers, the Nusselt number increases with the increase of fin pitch.

The numerical results presented in this paper may provide some useful guidance in the design of the wavy fin‐and‐tube heat exchanger with large number of rows of tubes.

Underwater robots are one of the effective solutions for underwater exploration. Fish's swimming motion is more effective and efficient than propeller screw propulsion which is more popular for underwater vehicles. So far, a lot of fish‐like robots that have several actuated joints have been developed. They realize arbitrary motion by controlling the joint angles simultaneously. On the other hand, using an elastic fin may reduce the number of actuated joints and the total energy consumption. The purpose of this paper is to develop a fish‐like robot driven by a single actuator with an elastic tail fin.

Since an elastic plate appropriately bends due to the interaction to the surrounding fluid, a robot with the elastic fin can swim smoothly even though it has only a single actuated joint. However, in order to improve the swimming performances, it is required to optimize the shape of fin (width, thickness, distribution, etc.). Although computational fluid dynamics technique is one of the methods to assess the effectiveness of a certain shape of fin, it may take longer to obtain the results. Therefore, in this study, a simplified simulator is constructed and a better shape of fin is explored.

Four types of fin shape were prepared and the swimming experiments were conducted. The swimming velocity changed according to the frequency and the shape of fin. In order to find the optimal shape of fin, the simulator of five‐link model surrounded by fluid is constructed. The differences of velocity can be found according to the parameters of fin shape. The simulation showed the similar trend as the experiments although the absolute values of velocity did not correspond. It is thought that the developed simulator can estimate the relative performance of fins.

Most fish robots that have been developed so far consist of rigid links and multi‐actuated joints, which can realize arbitrary motion by controlling the joint angles simultaneously. On the other hand, using an elastic plate as a tail fin may reduce the number of actuated joints and the total energy consumption although it is not easy to realize arbitrary attitude. In this paper, a fish‐like robot driven by a single actuator with an elastic tail fin was developed. This technique makes the mechanism of a fish‐like robot simple.

A three‐dimensional numerical study was conducted to assess the heat transfer performance of extended fins in a two‐row finned tube heat exchanger. Fins under investigation were plane and slit types. A finite volume discretization method and a SIMPLE‐based solution algorithm were, respectively, applied to working differential equations and their discrete counterparts to compute the gas velocities and pressure. The temperatures of solid and gas phases were computed from the same energy equation with different diffusivities and prescribed convective fluxes. The main objective of this study was to compare the transfer capabilities of the two investigated fin shapes. Their capabilities as a whole are presented in terms of the computed Nusselt number and the pressure drop across the flow passage.

To find the optimal geometries of rectangular and cylindrical fins for maximum heat dissipation.

The objective function for finding the optimized profiles of fins are solved by using the genetic algorithms (GAs). A range of fin shapes are investigated and the optimum solutions for various profile area are obtained.

Provide information to thermal engineers to what extent any particular extended surface or fin arrangements could improve heat dissipation from a surface to the surrounding fluid. Smaller fin volume in fin design is preferable as the heat is dissipated more effectively.

A new method of using GA for optimization of fins is used here. The value of this paper lies in providing data for selecting suitable fins for thermal management in electronic systems.

Limited to cases where the correlations for heat transfer coefficients are valid.

A very useful finding for practising thermal engineer especially in the area of electronic packaging as the parameters for the fin design can easily be found for any chosen profile area.

This paper aims to seek purely analytical results relying on the physical parameters including the temperature jump parameter.

The exponential fin profiles and heat transfer enhancement influenced by a temperature jump at the base are the main targets of this paper.

The introduced temperature slip at the base penetrates through the surface of the fin and reorganizes the distribution of temperature all over the surface. The overall impact of the temperature jump on the fin efficiency is such that it acts to lower the fin efficiency. However, the efficiency of the exponential fin is increasing for growing shape exponential fins as compared to the rectangular and decaying ones. Hence, exponential fins amenable to certain temperature jump has significance in technological cooling processes. Finally, the optimum dimensions regarding the base fin thickness and the fin length of the exponential profiles are assessed by means of optimizing the base heat transfer rate given a cross-sectional area.

Exact solutions are provided for optimum exponential type fins subjected to a temperature jump. The optimum dimensions regarding the base fin thickness and the fin length of the exponential profiles are assessed.

This study examines the impact of financial inclusion on the corporate sustainability of banks in both Organization of Islamic Cooperation (OIC) and non-OIC emerging economies, considering the COVID-19 pandemic.

The research utilizes data from 3,159 bank-years from 2007 to 2021 across 33 emerging markets.

Empirical findings indicate that firms operating in higher financial inclusion developing countries tend to exhibit higher levels of sustainable development. This positive relationship has become even more pronounced during the COVID-19 pandemic, suggesting the importance of financial inclusion in fostering corporate sustainability, especially in times of economic challenges. Interestingly, while the positive correlation between financial inclusion and sustainable development remains consistent across both OIC and non-OIC countries, firms in OIC countries do not show significant changes during the pandemic.

This observation suggests that the pandemic’s impact on corporate sustainability may vary between the two groups of countries. This study highlights the significance of financial inclusion in promoting corporate sustainability in developing economies. In times of recessions when accessing finance becomes expensive, policymakers in OIC countries should identify firms that adhere to Islamic principles, such as those sensitive to interest rates, and provide them with targeted support. This assistance can enable these companies to compete effectively and achieve their financial sustainability objectives.

There has been no attempt to investigate the effect of financial inclusion and the pandemic on the sustainable development of banks in developing countries.