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Nanofluids’ properties made them interesting for various areas like engineering, medicine or cosmetology. Discussed here, research pertains to specific problem of heat transfer enhancement with application of the magnetic field. The main idea was to transfer high heat rates with utilization of nanofluids including metallic non-ferrous particles. The expectation was based on changed nanofluid properties. However, the results of experimental analysis did not meet it. The heat transfer effect was smaller than in the case of base fluid. The only way to understand the process was to involve the computational fluid dynamics, which could help to clarify this issue. The purpose of this research is deep understanding of the external magnetic field effect on the nanofluids heat transfer.

In presented experimental and numerical studies, the water and silver nanofluids were considered. From the numerical point of view, three approaches to model the nanofluid in the strong magnetic field were used: single-phase Euler, Euler–Euler and Euler–Lagrange. In two-phase approach, the momentum transfer equations for individual phases were coupled through the interphase momentum transfer term expressing the volume force exerted by one phase on the second one.

Therefore, the results of numerical simulation predicted decrease of convection heat transfer for nanofluid with respect to pure water, which agreed with the experimental results. The experimental and numerical results are in good agreement with each other, which confirms the right choice of two-phase approach in analysis of nanofluid thermo-magnetic convection.

The Euler–Lagrange exhibit the best matching with the experimental results.

The paper deals with a problem of control of a mixed, discrete‐continuous dynamic process. The set of input data for such a process is finite. Control of such a process is very difficult due to the non‐polynomial computational complexity of the used algorithm. The paper suggests a formulation of the optimization problem as well as a method for its solution. The described method is applied to an industrial process, and particularly to the system conditioned by time for which the set of control operations changes according to the realization of the production process.

The objective of this study is to present a successful strategy to promote Korea as the logistics hub of Northeast Asia. Firstly, we introduce the necessity of a logistic hub strategy for Korea. In order to develop a successful strategy, we consider the 'free trade zone' model of the Netherlands and China. We develop a realistic and suitable model for Korea based on this Jree trade zone' model. Our proposal for a successful logistic hub strategy for Korea is the fulfillment of the following six objectives: 1) security of market accessibility, 2) improvement of the logistic system, 3) improvement of the education system, 4) improvement of the tax system, 5) assurance of labor market flexibility, and 6) development of an appealing living environment for foreigners.

Metal-cooled reactors generally use molten metals such as sodium, potassium or a combination of sodium and potassium because of their excellent heat transfer properties so that the reactor can operate at much lower pressures and higher temperatures. The purpose of this paper is to investigate the stability of natural convection in an inclined ring filled with molten potassium under the influence of a radial magnetism.

A numerical simulation of electrically conductive fluid natural convection stability is performed on an inclined cylindrical annulus under the influence of a radial magnetism. The upper and lower walls are adiabatic, while the internal and external cylinders are kept at even temperatures. The equations governing this fluid system are solved numerically using finite volume method. The SIMPLER algorithm is used for pressure-speed coupling in the momentum equation.

Numerical results for various effective parameters that solve the problem in the initial oscillatory state are discussed in terms of isobars, isotherms and flow lines in the annulus for a wide range of Hartmann numbers (0 ≤ Ha ≤ 80), inclination angles (0 ≤ γ ≤ 90°) and radii ratios λ ≤ 6. The dependency stability diagrams between complicated situations with the critical value of the Rayleigh number RaCr and the corresponding frequency FrCr are established on the basis of the numeric data of this investigation. The angle of inclination and the radii ratio of the annulus have a significant effect on the stabilization of the magneto-convective flux and show that the best stabilization of the natural oscillatory convection is obtained by the intensity of the strongest magnetic field, the high radii ratio and inclination of the annulus at γ = 30°.

This numerical model is selected for its various applications in technology and industry.

To the best of the authors’ knowledge, the influence of the inclination of the cylindrical annulus (ring), with various radii ratio, on natural oscillatory convection under a radial magnetism has never been investigated.

Following the self‐equilibrating stress systems developed for the single‐cell fuselage, further stress systems are given for the fuselage with a double‐cell cross‐section. These allow for the direct stress carrying ability of the floor. Wing‐fuselage interaction redundancies are discussed in detail and suitable self‐equilibrating load systems presented. The formation of the associated stress systems in the cover is described with reference to their generation inside the computer. Chapter IV concludes with a brief account of fin attachment loads which serves to introduce two further interaction redundancies to take account of skin attachment. The opening section of Chapter V relates the detailed frame loads to the overall fuselage loading preparatory to the analysis of the closed frames. Matrix equations for the calculation of the statically equivalent wing reactions and of the fuselage moment diagrams are given.

To provide water utilities operating under rationing conditions with some insight into issues related to managing non‐revenue water (NRW).

Reviews general theories associated with pressure, surges and water leakage, and compares them with real data in a rationed water distribution system.

In water networks there is a strong relationship between rationing hours and rationing surge pressures and NRW levels. These relationships mean that traditional ways of benchmarking NRW are not useful in rationed systems.

This paper identifies key NRW issues for utilities operating under rationing and gives them help in identifying options for their NRW strategies.

Outlines the findings of a study into the secondary destination choices of tourists visiting the Philippines. Defines the tourist mega‐system. Looks at the framework and methodology used and attempts to link these with the holistic approach of Jafari regarding tourism structure and stages which the tourists go through.

Introduction Recent changes in subscriptions to the Northern Regional Library System, together with certain alterations in the constitution, have led academic libraries to consider alternatives. We investigated two main factors: the cost of borrowing through the region as opposed to directly from the British Library, and the quality of service of each. No attempt has been made to estimate possible rises in postal or BLLD form charges. No administrative costs have been guessed for such things as notifying the NRLB of acquisitions and withdrawals. We have not forecast how Boston Spa would cope with extra business. Our efforts have been directed to a relatively unsophisticated comparison.

The purpose of this study is to investigate the impact of the oscillatory movement on heat transfer within a double periodic lid-driven cubic enclosure filled with copper-water nanofluid and to figure out how the oscillations impact the fluid flow and thermal behavior inside the enclosure. The authors asserted that this study will help to improve the heat transfer efficiency and the thermal performance of various technical engineering equipments.

The cubic enclosure is heated differentially; the left side is cold, the right one is warm and the remaining walls are insulated. Based on the movement directions of the upper and bottom lids, two cases for lid-driven walls are examined (Case 1: same movement for both lids; Case 2: opposite movement for the lids). The finite volume approach was implemented to solve the time-dependent three-dimensional momentum and energy equations, adopting the power low as a scheme of resolution. The numerical study was carried out for a range of parameters: volume fraction (0 ≤ φ ≤ 0.06), Richardson number (0.1 ≤ Ri ≤ 10), non-dimensional lid frequency (2π/50 ≤ Ω ≤ 2π/10) and fixed Grashof number 105.

The numerical simulations were executed for two different cases of the direction of the motion of the oscillatory lids. Based on the findings obtained, decreasing the Richardson number with low lids frequency gives the best heat transfer enhancement for both cases. Furthermore, in the same conditions, swapping from Case 2 to Case 1 leads to enhancing the maximum average Nusselt number obtained by 29.74%. At a high Richardson number, using high lids frequency increases the heat transfer rate compared to using low lids frequency (an enhancement of 4.32% for Case 1 and 3.63% for Case 2). The best heat transfer rate was established for Case 1 when the lids move positively, transporting the cold flow to the hot side. In all cases, increasing the concentration of nanoparticles improves the heat transfer.

The current study gives an understanding of the problem of mixed convection in a cubic enclosure with oscillatory walls, which has received little attention. And also, there has been no study published on unsteady mixed convection within a double oscillatory lid-driven cavity.