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The potential flow field for the transitional region in a constant radius, two‐dimensional duct was studied. The potential velocity and pressure profiles in various duct geometries with different turning angles and duct heights were investigated. A generalized solution of potential flow in a transitional bend was obtained.

The Russian export flow is highly concentrated on few trading partners that results in its high vulnerability to external shock. Furthermore, the Russian–Ukraine conflict and corresponding western sanctions has enhanced the need of export markets diversification for Russia. Therefore, this study is a baseline attempt to explore determinants of export flow along with identifying potential export markets. This objective is realized by employing an augmented version of gravity model on export flow of Russian Federation to 108 trading partners from 2000 to 2020.

The augmented gravity model of export flow is estimated by using employing contemporary panel econometrics such as panel generalized ordinary least square estimation technique with cross-sectional weight along with heteroskedasticity consistent white coefficients is employed to explore impact of selected macroeconomic and policy variables. Furthermore, the sensitivity analysis is performed by using panel random effect along with the Driscoll–Kraay standard errors with pooled ordinary least squares (OLS) regression and random effect generalized least square (GLS) estimator techniques. The estimated result of panel GLS technique is subjected to in-sampled forecasting technique to explore potential export markets.

The findings show that an increase in the income of trading partners and enhancement of domestic production capacity has significant positive impact on Russian export flow, whereas geographic distance has a significant negative impact. Income of trading partners emerged as major determinant of export flow with high explanatory power. Among augmented variables, the real exchange rate reveals a significant positive impact of lower intensity, whereas binary variables for the common border, common history and preferential/free trade agreement show a significant positive impact. The finding of export potential reveals a high concentration of export with existence of large potential for exports across the globe. For instance, many developing countries in Asia, Africa and America reveal high potential for Russian exports.

The findings urge Russian Federation to diversify its export markets by targeting potential export markets. Many emerging developing countries are witnessing a high potential for Russian exports, therefore attempts should be taken to diversify toward them. The expansion of existing transportation facilities along with development of cargo trade can be important policy instrument to realize objective of export diversification.

This study is the first comprehensive analysis that employs augmented gravity model to explore potential export markets for Russian Federation by using panel data of 108 global trading partners from 2000 to 2020. This finding of this study provides a framework of export diversification toward potential markets across the globe.

The purpose of this paper is to consider reconstructions of potential 2D fields from discrete measurements. Two potential processes are addressed, steady flow and heat conduction. In the first case, the flow speed and streamlines are determined from the discrete data on flow directions, in the second case, the temperature and flux are recovered from temperature measurements at discrete points.

The method employs the Trefftz element principle and the collocation. The domain is seen as a combination of elements, where the solution is sought as a linear holomorphic function a priori satisfying the governing equations. Continuity of piecewise holomorphic functions is imposed at collocation points located on the element interfaces. These form the first group of equations. The second group of equations is formed by addressing the measured data, therefore the matrix coefficients may reflect experimental errors. In the case of fluid flow, all equations are homogeneous, therefore one normalising equation is added, which provides existence of a non‐trivial solution. The system is over‐determined; it is solved by the least squares method.

For the heat flow problem, the determination of heat flux is unique, while for the fluid flow, the determined streamlines are unique and the determination of speed contains one free multiplicative positive constant. Several examples are presented to illustrate the methods and investigate their efficiency and sensitivity to noisy data.

The approach can be applied to other 2D potential problems.

The paper studies two novel formulations of the reconstruction problem for 2D potential fields. It is shown that the suggested numerical method is able to deal directly with discrete experimental data.

This study aims at developing a comprehensive model for the analysis of electro-osmotic flow (EOF) through a fluid-saturated porous medium. To fully understand and exploit a number of applications, such a model for EOF through porous media is essential.

The proposed model is based on a generalised set of governing equations used for modelling flow through fluid saturated porous media. These equations are modified to incorporate appropriate modifications to represent electro-osmosis (EO). The model is solved through the finite element method (FEM). The validity of the proposed numerical model is demonstrated by comparing the numerical results of internal potential and velocity distribution with corresponding analytical expressions. The model introduced is also used to carry out a sensitivity analysis of the main parameters that control EOF.

The analysis carried out confirms that EO in free channels without porous obstruction is effective only at small scales, as largely discussed in the available literature. Using porous media makes EO independent of the channel scale. Indeed, as the channel size increases, the presence of the charged porous medium is essential to induce fluid flow. Moreover, results demonstrate that flow is significantly affected by the characteristics of the porous medium, such as particle size, and by the zeta potential acting on the charged surfaces.

To the best of the authors’ knowledge, a comprehensive FEM model, based on the generalised equations to simulate EOF in porous media, is proposed here for the first time.

The purpose of this paper is to investigate electrokinetic and mixed convection (pressure gradient and buoyancy) effects on reverse flow formation at the channel walls.

The electrical potential distribution was modelled using the Poisson–Boltzmann equation while the governing momentum and energy equations are modelled from the Navier–Stokes equations and solved exactly.

It is found that flow reversal at the walls is enhanced by electrokinetic parameter whereas increasing degree of asymmetric parameter up to symmetric heating eliminates reverse flow formation at the walls no matter the electric charge distribution.

The results of this paper indicate that degree of asymmetric heating, mixed convection parameter and electrokinetic parameter regulate fluid velocity, rate of heat transfer, skin friction and reverse flow formation at the walls.

The numerical solution of problems involving two‐dimensional flow in an infinite or a semi‐infinite channel is considered. Beyond a certain finite region, where the flow and geometry may be general, a “tail” region is assumed where the flow is potential and the channel is uniform. This situation is typical in many cases of fluid‐structure interaction and flow around obstacles in a channel. The unbounded domain is truncated by means of an artificial boundary B, which separates between the finite computational domain and the “tail.” On B, special boundary conditions are devised. In the finite computational domain, the problem is solved using a finite element scheme. Both non‐local and local artificial boundary conditions are considered on B, and their performance is compared via numerical examples.

This paper aims to model the aerodynamic flow characteristics of NACA0010 for various angle of attacks including stall for incompressible flows using panel methods. This paper also aims to quantify the surface pressure distribution on streamlined bodies and validate the results with analytical Jukouwski method and inverse panel methods that can predict the aerodynamic flow behaviour using the geometric iteration approach.

The 2 D panel method was implemented in Qblade software v.06 which uses the fundamental panel method which rely on source strengths and influence coefficients to determine the velocity and pressure fields on the surface. The software implements the boundary layer or viscous effects to determine the influence on aerodynamic performance at various angles of attack. Jukouwski method is also evaluated for predicting aerodynamic characteristics and is based on the geometric iteration approach. Then complex aerodynamic flow potentials are determined based on the source strengths which are used to predict the pressure and velocity fields.

At low to moderate angles of attack, panel and Jukouwski methods predict similar results for surface pressure coefficients comparable to Hess and Smith inverse method. In comparison to panel method, results from the Jukouwski mapping method predicted the pressure coefficient conservatively for the same free stream conditions. With increase in Reynolds number, lift coefficient and aerodynamic performance improved significantly for un-tripped aerofoil when stall angle is approached when compared to tripped aerofoil.

This study demonstrated that panel methods have higher efficacy in terms of computational time or resources and thus can provide benefits to many real-world aircraft or aerospace design applications.

Even though panel and Jukouwski methods have been studied extensively in the past, this paper demonstrates the efficacy of both methods for modelling aerodynamic flows that range between moderate to high Reynolds number which are critical for many aircraft applications. Both methods have been validated with analytical and inverse design methods which are able to predict aerodynamic flow characteristics for simple bluff bodies, streamlined aerofoils as well as bio-inspired corrugated aerofoils.

The purpose of this paper is to test flow as a construct distinctly separate from its antecedents, and the resulting impact on brand attitudes and purchase intent within realistic online shopping three-dimensional virtual environments (3-DVEs).

This research utilizes a field study, combined with a survey research design of 348 3-DVE participants.

The findings reveal that flow is not a unidimensional construct but rather, a mental state that should be measured separately from its antecedents, with the possibility that certain antecedents may be more relevant than others in different activities. Furthermore, the authors received strong support for the overarching hypothesized model separating the nine dimensions associated with engagement in an activity as antecedents of flow, which, in turn, influences brand attitude and thereafter purchase intention.

This study was limited to one type of activity within one 3-DVE but is balanced by the difficulty in gaining access to organizations and computer-mediated environments of this type for examining such phenomena.

Businesses using 3-DVEs to market brands should focus their efforts on creating highly enjoyable experiences that result in the feeling of a loss of sense of time for the participants in order to ultimately positively influence purchase intentions.

Prior research focused on fantasy-based, game-oriented environments, while also neglecting to test all elements of flow, examining “similar to flow” constructs or measuring flow as a unidimensional construct.

This study explores the concept of hydraulic flushing gate with an automated control system as a flow control structure of the urban storm water system. The research team has implemented a flush gate with the automated control system to the flow of the water in a drainage channel. The flow control structure was used to determine the effectiveness of such design by applying the concept of virtually on a real-world drainage system at Jalan Astana, Kuching. Computer representations of the existing drainage system and flow control structure were built using EPA SWMM 5.0 model. The series of flow control structure was proven to hold the runoff from 10-year storm. The modelling result shows that there is 25.9% of flow reduction at outlet node. As a modification of the existing drainage system in the urban area involves high construction cost, by installing a flow control structure in the drainage system is an innovative way to control the flow of the water.

Virtual reality (VR) is of increasing interest to marketers because it can be used to explore and proactively shape long-term futures, co-create value with consumers, and foster consumer-brand engagement. Yet, to date, the field lacks a cohesive framework for approaching VR research; thus, the objective of this systematic literature review is to provide such a framework and highlight research opportunities.

First, after conducting a systematic literature review, we highlight VR themes instrumental to flow and propose a typology for VR research using realism-fantasy and immersion as dimensions. Next, we review the current state of empirical research for each quadrant. Finally, we synthesize research within each quadrant, specifying criteria and considerations for conducting research. In doing so, we propose an agenda for marketing research, centered on methodological, future studies, and consumer-related contributions.

VR themes instrumental to flow include the avatar, application quality, and interactivity. We find, contrary to some conceptualizations of VR, that all applications are capable of producing flow. Conflicting research and gaps are highlighted in the findings section and summarized in Table III. Additionally, while prior research seems to draw from findings of other VR applications in advancing knowledge in general, the results of the literature review suggest that VR applications should be treated uniquely. Finally, we propose highly immersive VR applications as more conducive to future studies research.

Scholars can utilize the findings to prioritize future research studies in marketing. By following the typology and research opportunities, scholars can advance marketing theory and enhance the external validity of research studies through VR applications.

Managers can utilize the findings to ascertain consumers and societies‘ responses to various marketing stimuli, with implications for product development, branding, retail/service experiences, adoption of new technologies, tourism, and many other domains. VR applications offer managers more ways of testing concepts and processes in realistic fashion without the costs and risks associated with more traditional methods.

The objective of this paper is to examine varying opportunities for VR research given flow and fantasy potential and to prioritize VR research.