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Identifying the flow regime is a prerequisite for accurately modeling two-phase flow. This paper aims to introduce a comprehensive data-driven workflow for flow regime identification.

A numerical two-phase flow model was validated against experimental data and was used to generate dynamic pressure signals for three different flow regimes. First, four distinct methods were used for feature extraction: discrete wavelet transform (DWT), empirical mode decomposition, power spectral density and the time series analysis method. Kernel Fisher discriminant analysis (KFDA) was used to simultaneously perform dimensionality reduction and machine learning (ML) classification for each set of features. Finally, the Shapley additive explanations (SHAP) method was applied to make the workflow explainable.

The results highlighted that the DWT + KFDA method exhibited the highest testing and training accuracy at 95.2% and 88.8%, respectively. Results also include a virtual flow regime map to facilitate the visualization of features in two dimension. Finally, SHAP analysis showed that minimum and maximum values extracted at the fourth and second signal decomposition levels of DWT are the best flow-distinguishing features.

This workflow can be applied to opaque pipes fitted with pressure sensors to achieve flow assurance and automatic monitoring of two-phase flow occurring in many process industries.

This paper presents a novel flow regime identification method by fusing dynamic pressure measurements with ML techniques. The authors’ novel DWT + KFDA method demonstrates superior performance for flow regime identification with explainability.

Subcooled flow boiling phenomenon is characterized by coolant phase change in the vicinity of the heated wall. Although coolant phase change from liquid to vapour phase significantly enhances the heat transfer coefficient due to latent heat of vaporization, eventually the formed vapor bubbles may coalesce and deteriorate the heat transfer from the heated wall to the liquid phase. Due to the poor heat transfer characteristics of the vapour phase, the heat transfer rate drastically reduces when it reaches a specific value of wall heat flux. Such a threshold value is identified as critical heat flux (CHF), and the phenomenon is known as departure from nucleate boiling (DNB). An accurate prediction of CHF and its location is critical to the safe operation of nuclear reactors. Therefore, the present study aims at the prediction of DNB type CHF in a hexagonal sub-assembly.

Computational fluid dynamics (CFD) simulations are performed to predict DNB in a hexagonal sub-assembly. The methodology uses an Eulerian–Eulerian multiphase flow (EEMF) model in conjunction with multiple size group (MuSiG) model. The breakup and coalescence of vapour bubbles are accounted using a population balance approach.

Bubble departure diameter parameters in EEMF framework are recalibrated to simulate the near atmospheric pressure conditions. The predictions from the modified correlation for bubble departure diameter are found to be in good agreement against the experimental data. The simulations are further extended to investigate the influence of blockage (b) on DNB type CHF at low operating pressure conditions. Larger size vapour bubbles are observed to move away from the corner sub-channel region due to the presence of blockage. Corner sub-channels were found to be more prone to experience DNB type CHF compared to the interior and edge sub-channels.

An accurate prediction of CHF and its location is critical to the safe operation of nuclear reactors. Moreover, a wide spectrum of heat transfer equipment of engineering interest will be benefited by an accurate prediction of wall characteristics using breakup and coalescence-based models as described in the present study.

Simulations are performed to predict DNB type CHF. The EEMF and wall heat flux partition model framework coupled with the MuSiG model is novel, and a detailed variation of the coolant velocity, temperature and vapour volume fraction in a hexagonal sub-assembly was obtained. The present CFD model framework was observed to predict the onset of vapour volume fraction and DNB type CHF. Simulations are further extended to predict CHF in a hexagonal sub-assembly under the influence of blockage. For all the values of blockage, the vapour volume fraction is found to be higher in the corner region, and thus the corner sub-channel experiences CHF. Although DNB type CHF is observed in corner sub-channel, it is noticed that the presence of blockage in the interior sub-channel promotes the coolant mixing and results in higher values of CHF in the corner sub-channel.

This paper aims to present a novel approach for computing particle temperatures in simulations coupling computational fluid dynamics (CFD) and discrete element method (DEM) to predict flow and heat transfer in fluidized beds of thermally thick spherical particles.

An improved lumped formulation based on Hermite-type approximations for integrals to relate surface temperature to average temperature and surface heat flux is used to overcome the limitations of classical lumped models. The model is validated through comparisons with analytical solutions for a convectively cooled sphere and experimental data for a fixed particle bed. The coupled CFD-DEM model is then applied to simulate a Geldart D bubbling fluidized bed, comparing the results to those obtained using the classical lumped model.

The validation cases demonstrate that ignoring internal thermal resistance can significantly impact the temperature in cases where the Biot number is greater than 0.1. The results for the fixed bed case clearly demonstrate that the proposed method yields significantly improved outcomes compared to the classical model. The fluidized bed results show that surface temperature can deviate considerably from the average temperature, underscoring the importance of accurately accounting for surface temperature in convective heat transfer predictions and surface processes.

The proposed approach offers a physically more consistent simulation without imposing a significant increase in computational cost. The improved lumped formulation can be easily and inexpensively integrated into a typical DEM solver workflow to predict heat transfer for spherical particles, with important implications for various industrial applications.

The purpose of this paper is to reveal the solute segregation behavior in the molten and solidified regions during direct chill (DC) casting of a large-size magnesium alloy slab under no magnetic field (NMF), harmonic magnetic field (HMF), pulsed magnetic field (PMF) and two types of out-of-phase pulsed magnetic field (OPMF).

A 3-D multiphysical coupling mathematical model is used to evaluate the corresponding physical fields. The coupling issue is addressed using the method of separating step and result inheritance.

The results suggest that the solute deficiency tends to occur in the central part, while the solute-enriched area appears near the fillet in the molten and solidified regions. Applying magnetic field could greatly homogenize the solute field in the two-phase region. The variance of relative segregation level in the solidified cross-section under NMF is 38.1%, while it is 21.9%, 18.6%, 16.4% and 12.4% under OPMF2 (the current phase in the upper coil is ahead of the lower coil), HMF, PMF and OPMF1 (the current phase in the upper coil lags behind the lower coil), respectively, indicating that OPMF1 is more effective to reduce the macrosegregation level.

There are few reports on the solute segregation degree in rectangle slab under magnetic field, especially for magnesium alloy slab. This paper can act a reference to make clear the solute transport behavior and help reduce the macrosegregation level during DC casting.

For a better understanding of the preferences and differences of young consumers in emerging wine markets, this study aims to propose a clustering method to segment the super-new generation wine consumers based on their sensitivity to wine brand, origin and price and then conduct user profiles for segmented consumer groups from the perspectives of demographic attributes, eating habits and wine sensory attribute preferences.

We first proposed a consumer clustering perspective based on their sensitivity to wine brand, origin and price and then conducted an adaptive density peak and label propagation layer-by-layer (ADPLP) clustering algorithm to segment consumers, which improved the issues of wrong centers' selection and inaccurate classification of remaining sample points for traditional DPC (DPeak clustering algorithm). Then, we built a consumer profile system from the perspectives of demographic attributes, eating habits and wine sensory attribute preferences for segmented consumer groups.

In this study, 10 typical public datasets and 6 basic test algorithms are used to evaluate the proposed method, and the results showed that the ADPLP algorithm was optimal or suboptimal on 10 datasets with accuracy above 0.78. The average improvement in accuracy over the base DPC algorithm is 0.184. As an outcome of the wine consumer profiles, sensitive consumers prefer wines with medium prices of 100–400 CNY and more personalized brands and origins, while casual consumers are fond of popular brands, popular origins and low prices within 50 CNY. The wine sensory attributes preferred by super-new generation consumers are red, semi-dry, semi-sweet, still, fresh tasting, fruity, floral and low acid.

Young Chinese consumers are the main driver of wine consumption in the future. This paper provides a tool for decision-makers and marketers to identify the preferences of young consumers quickly which is meaningful and helpful for wine marketing.

In this study, the ADPLP algorithm was introduced for the first time. Subsequently, the user profile label system was constructed for segmented consumers to highlight their characteristics and demand partiality from three aspects: demographic characteristics, consumers' eating habits and consumers' preferences for wine attributes. Moreover, the ADPLP algorithm can be considered for user profiles on other alcoholic products.

This study aims to investigate the research question: how do women leaders in the professional business services (PBS) sector develop and approach workplace (in)authenticity?

Ten senior women leaders in the Midlands region of the UK were purposefully selected and interviewed. A semi-structured approach meant that the author adopted a social constructionist paradigm and feminist interpretation. Questions were designed to elicit rich descriptions from the participants. An inductive thematic analysis was conducted to address the study’s purpose.

Four themes were important to women when they developed and approached workplace (in)authenticity: (1) Power Structures, (2) Fit to Belong, (3) Influential Femininity and (4) Through Her Evolution. Women described masculine-majority organisations exerting power. They were pressured into altering their behaviours to “fit” into workplaces. When women had the latitude to be themselves, their leadership excelled. Women’s authenticity developed through increased self-knowledge, helping them to overcome workplace challenges. The study concluded that women face complexities when developing and approaching their constructions of authenticity, namely in the barriers and ramifications they face.

The study suggests several implications for practice and theory concerning enablers and barriers to women leaders' workplace authenticity. The link between authenticity and workplace gender equity needs to be investigated.

The study provides evidence that women are challenged when becoming authentic, therefore, altering their careers irrecoverably in some cases.

This chapter examines representations of gender in online modafinil markets. While gender has often been absent from scholarship on online drug markets, our analysis demonstrates the ubiquity of gender in representations of modafinil users and sellers. The analysis draws on visual images, blogs, and marketing emails relating to three websites selling modafinil, discussed pseudonymously. We describe the range of ways that notions of gender are represented in advertising. Although women represent around 40% of that buying modafinil online, websites and communications tended not to feature women. Although sexist stereotypes of women were rarely present (in contrast to direct-to-consumer pharmaceutical advertising), the ways that modafinil was imagined tended to focus narrowly on corporate spheres of work and productivity. We contrast this narrow imaginary with female journalists’ own accounts of using modafinil to manage illness and enhance creativity. Thus, we conclude that the ways that modafinil has been imagined reflects working assumptions as to who is considered the ‘normal’ participant in online modafinil markets.

This paper examines the main drives of encouraging Iranian investors in the Turkish real estate market, focusing on the interface between push factors and pull factors that drive them abroad.

This paper examines the main drives of encouraging Iranian investors in the Turkish real estate market, focusing on the interface between push factors and pull factors that drive them abroad. For this purpose, the trend of housing price growth in Iran and Turkey was compared. The review of the 11-year trend of rates shows that housing prices in both countries have been continuously rising, and these prices have undoubtedly experienced increasing shocks in Iran. For further analysis, 13 main variables leading to the repulsion of investment in Iran's housing market and 15 variables shaping the attractiveness of investment in Turkey were identified in this sector. Thirty experts subsequently ranked the significant variables based on a closed-end questionnaire using quantitative strategic planning matrix. Examining housing investment elasticity in Turkey also shows that “Turkey's economic stability compared to neighboring countries” and “acquiring Turkish citizenship through real estate investment” are among the most important variables. On the other hand, the pressure variables of housing investment in Iran were “decrease in the value of the Iranian currency in recent years,” “currency price fluctuations” and “severe fluctuations and instability in the Iranian housing market.”

Examining housing investment elasticity in Turkey also shows that “Turkey's economic stability compared to neighboring countries” and “acquiring Turkish citizenship through real estate investment” are among the most important variables. On the other hand, the pressure variables of housing investment in Iran were “decrease in the value of the Iranian currency in recent years,” “currency price fluctuations” and “severe fluctuations and instability in the Iranian housing market.”

From a theoretical standpoint, foreign investment is in support of Turkey and harmful to Iran because the Turkish government is bolstering investment attractiveness to bring increased capital inflows into this country. Practically speaking, Turkey has aimed to create a rational framework for investors by strengthening and changing its economic system, as well as amending existing constitutions in this domain. Nevertheless, Iran resists any changes in its economic system and legislation. Therefore, a wide range of attractiveness and repulsion variables has led to the migration of Iranian investors to Turkey. In the present study, such variables are illuminated.