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The results from a direct numerical simulation (DNS) of turbulent, incompressible flow through a square duct, with an imposed temperature difference between the horizontal walls, are presented. The vertical walls are assumed perfectly insulated, and the Reynolds number, based on the bulk velocity and the hydraulic diameter, is about 4400. Our results indicate that secondary motions do not affect dramatically global parameters, like the friction factor and the Nusselt number, with respect to the plane‐channel flow, but the distributions of the local shear stress and heat flux at the walls are highly non‐uniform, due to the presence of these secondary motions. It is also shown that an eddy‐diffusivity approach is capable to reproduce well the turbulent heat flux. All simulations were performed by an efficient finite volume algorithm. A description of the numerical algorithm, together with an analysis of time‐accuracy, is included. The OpenMP parallel programming language was exploited to obtain a moderately‐scalable application.

Current issues of Publishers' Weekly are reporting serious shortages of paper, binders board, cloth, and other essential book manufacturing materials. Let us assure you these shortages are very real and quite severe.

Computational fluid dynamics (CFD) simulation of the flow field around marine propellers is challenging because of geometric complexity and rotational effects. To capture the flow structure, grid quality and distribution around the blades is primordial. This paper aims to demonstrate that solution-based automatic mesh optimization is the most logical and practical way to achieve optimal CFD solutions.

In the current paper, open water propeller performance coefficients such as thrust and torque coefficients are numerically investigated. An anisotropic mesh adaptation technique is applied, believed for the first time, to marine propellers and to two computational domains.

The current study’s performance coefficients are compared with other previously published CFD results and improvements in terms of accuracy and computational cost are vividly demonstrated for different advance coefficients, as well as a much sharper capture of the complex flow features.

It will be clearly demonstrated that these two improvements can be achieved, surprisingly, at a much lower meshing and computational cost.

This paper aims to explore digital fashion products in the metaverse platform contexts and empirically examine the effect of the metaverse platform characteristics on the purchase intention of digital fashion products through users' flow experience and perceived value of the products.

A survey method was used in this study. Answers from 314 metaverse users were analyzed, and the hypotheses were tested using the structural equations modeling and bootstrapping analysis.

The analyses showed that telepresence, social interaction and economic flow had significant effects on users' flow experience among the metaverse platform characteristics, while the continuity and content creation of the metaverse platform did not have significant effects. The flow experience also appeared to have significant effects on multiple consumption values, including pleasure value, self-expression value and economic value. Last, the perceived pleasure value and economic value of digital fashion products had a positive effect on purchase intention.

The main contribution of this research is that it is one of the first empirical attempts to investigate individual consumers' perceptions and experiences of digital fashion products in the context of metaverse platforms.

Meine ersten Worte seien ein Gruss und ein Dank. Ich heisse Sie meinerseits von Herzen willkommen. Vor allem aber spreche ich namens der Internationalen Vereinigung wissenschaftlicher Fremdenverkehrsexperten jenen, die uns hierher eingeladen und die zur Verwirklichung dieser Veranstaltung beigetragen haben, den tiefgefühlten Dank aus. Dieser gilt in erster Linie der österreichischen Bundesregierung, von der uns S. Exzellenz Dr. E. Kolh, der Herr Unterrichtsminister, die hohe Ehre seiner Anwesenheit und persönlichen Begrüssung erweist, die wir vollauf zu würdigen wissen. Es kann den österreichischen Behörden nicht hoch genug angerechnet werden, dass sie uns die Möglichkeit verschaffen, unsern vierten Kongress in Wien abzuhalten, das für uns einen Inbegriff hoher allgemeiner und zugleich touristischer Kultur bildet. Wenn die Aufnahme, die uns hier gewährt wird, vom Geiste einer Gastfreundschaft und Liebenswürdigkeit getragen ist, wie sie nicht mehr zu überbieten sind, so finden sich darin zugleich jene Vorstellungen bestätigt, die wir mit Österreich verbinden und wodurch dessen Land und Volk jedem einzelnen von uns so teuer wurden. In meinen aufrichtigen Dank seien nicht weniger alle eingeschlossen, die um die Vorbereitung und Organisation des Kongresses besorgt waren. Ich muss befürchten, Ungenauigkeiten und Ungerechtigkeiten zu begehen, wenn ich es unternehmen wollte, sie beim Namen zu nennen. Trotzdem kann und darf ich nicht unterlassen, unsern Freunden von der Österreichischen Verkehrswerbung und vom Institut für Fremdenverkehrsforschung an der Hochschule für Welthandel, an ihrer Spitze Herrn Doz. Dkfm. Dr. Paul Bernecker, die besondere Anerkennung für ihre verdienstvollen Bemühungen zum Ausdruck zu bringen. Jeder, der hinter die Kulissen sieht, weiss, welche Unmenge an Kleinarbeit und auch wie viele Unannehmlichkeiten manchmal mit der Vorbereitung derartiger Tagungen verknüpft sind. Unser Wunsch geht dahin, sie möchten mit dem heutigen Tage vergessen sein und unsere treuen Helfer würden nurmehr Genugtuung darüber empfinden, an einer guten Sache erfolgreich mitgewirkt zu haben — das einzige Entgelt übrigens, das wir ihnen zu bieten vermögen, das ihnen aber nebst unserer Verbundenheit in reichstem Masse gebührt und zukommen soll.

The purpose of this paper is to review Lean Six Sigma (LSS) literature and report different definitions, demographics, methodologies and industries.

This paper highlights various definitions by different researchers and practitioners. A total of 235 research papers has been reviewed for the LSS theme, research methodology adopted, type of industry, author profile, country of research and year of publication.

From the review, four significant LSS classifications were identified that deal with the spread of LSS in different industries followed by observation for classification.

LSS is a strategy for success, but it did not examine its presence in various Industries. From this paper, readers can understand the quantum of its spread before implementing LSS. For academicians, it will be a comprehensive list of papers for research.

This paper reviews 235 research papers for their year, author profile, research methodology and type of industry. Various characteristics of LSS definitions and their theme are also reviewed.

The purpose of this paper is to analyze numerically forced convective conjugate heat transfer characteristics for laminar flow through a wavy minichannel.

The mass and momentum conservation equations for the flow of water in the fluidic domain and the coupled energy conservation equations in both the fluid and solid domain are solved numerically using the finite element method. The exteriors of both the walls are subjected to a uniform heat flux.

The results reveal that the theoretical model without consideration of the effect of wall thickness always predicts a lower value of average Nusselt number ( Nu¯) as compared to the case of conjugate analysis, although it varies with the thickness as well as material of the wall. For the low amplitude of the wall (α = 0.2), the performance factor (PF) becomes very high for Re in the regime of 5 (⩽) Re (⩽) 15. For any geometrical configurations, conjugate heat transfer analysis predicts higher PF as compared to that of nonconjugate analysis.

The present study finds relevance in several applications, such as solar collectors and heat exchangers used in chemical industries and heating-ventilation and air-conditioning, etc.

To the best of the authors’ knowledge, the analysis of combined influences of the thickness and the material of the wall of the channel together with the geometrical parameters of the channel, namely, amplitude and wavelength on the heat transfer and fluid flow characteristics for flow through wavy minichannel in the laminar regime is reported first time in the literature.

The main purpose of this paper is the generation of the heat transfer and pressure drop correlations by considering three working fluids, namely air, water, and ethylene glycol, for the wavy plate-fin heat exchangers (PFHEs).

In order to present the general correlations, various models with different geometrical parameters should be tested. Because of the problems, such as difficult, long time, and costly fabrication of the wavy fins in experimental tests, computational fluid dynamics (CFD) calculations can be a useful method for the generation of the heat transfer and pressure drop correlations with eliminating the experimental problems. Hence, the effective design parameters of the wavy plate-fin, including fin pitch, fin height, wave length, fin thickness, wave amplitude, and fin length, and also their levels were recognized from the literature. The Taguchi method was applied to formulate the CFD simulation work.

The simulation results were compared and validated with an available experimental data. The mean deviations of the Colburn factor, j, and Fanning friction factor, f, values between the simulation results and the experimental data were 3.74 and 9.07 percent, respectively. The presented air correlations and experimental data were in a good agreement, so that approximately 95 percent of the experimental data were correlated within ±12 percent. The j factor values varied for the different working fluids, while the f factor values did not sensibly change.

The presented correlations can be used to estimate the thermal-hydraulic characteristics and to design of the compact PFHE with the wavy channels.

This manuscript presents the new correlations for the compact PFHEs with the way channels by considering all the geometrical parameters and the working fluids with the different Prandtl numbers, 0.7, 7, and 150.

This paper aims to offer an insight into the fundamental structural changes that the wine sector world‐wide is undergoing as a result of globalisation and mounting international competition.

The most important recent trends in wine production, consumption and distribution are analysed and possible future scenarios for the wine industry outlined. The constraints and opportunities that wine operators are facing and are likely to face in the future are also examined, as is competition between Old World and New World producers. In this context, an analysis of the structure of the Italian wine industry serves to underscore the importance of the local factor and its link to quality as a competitiveness tool.

Globalisation has boosted competition between Old and New World producers. However, varying structures of production suggest the appropriateness of adopting competitive strategies shaped according to the varying relationship between different producers and their distribution (and especially major retail chain) networks, notably with respect to quality segments. For Old World producers a very important role will be played by product differentiation and the combination of tradition and innovation.

This paper examines the options open to such producers, notably in Italy where strategies adopted vary according to economies of scale.

High speed axial flow pumps are widely used in aircraft fuel systems. Conventional axial flow pumps often generate radial secondary flows at partial-load conditions which influence the flow structure and form a “saddle-shaped” region in the Q-H curve that can destabilize the operation. Thus, the “saddle-shaped” Q-H region must be eliminated. The paper aims to discuss these issues.

The swept stacking method is often used for radial flow control in turbo-machinery impeller blade design. Hence, this study uses the swept stacking method to design a high speed axial flow pump. The detached eddy simulation method and experiments are used to compare the performance of a swept blade impeller in a high speed axial fuel pump with the original straight blade impeller. Both the pump performance and internal flow characteristics are studied.

The results show separation vortices in the impeller with the straight blade design at partial-load conditions that are driven by the rotating centrifugal force to gather near the shroud. The swept geometry provides an extra force which is opposite to the rotating centrifugal force that creates a new radial equilibrium which turns the flow back towards the middle of the blade which eliminates the vortices and the “saddle-shaped” Q-H region. The swept blade impeller also improves the critical cavitation performance. Analysis of the pressure pulsations shows that the swept blade design does not affect the stability.

This study is the initial application of swept blades for axial flow liquid pumps. The results show how the swept stacking changes the radial equilibrium of the high density, high viscosity flow and the effects on the mass transfer and pressure pulsations. The swept blade effectively improves the operating stability of high speed fuel pumps.