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The purpose of this paper is to perform the computational fluid dynamics (CFD) simulation with experimental validation to investigate the particle segregation effect in abrupt and smooth shapes circulating fluidized bed (CFB) risers.

The experimental investigations were carried out in lab-scale CFB systems and the CFD simulations were performed by using commercial software BARRACUDA. Special attention was paid to investigate the gas-particle flow behavior at the top of the riser with three different superficial velocities, namely, 4, 6 and 7.7 m/s. Here, a CFD-based noble simulation approach called multi-phase particle in cell (MP-PIC) was used to investigate the effect of traditional drag models (Wen-Yu, Ergun, Wen-Yu-Ergun and Richardson-Davidson-Harrison) on particle flow characteristics in CFB riser.

Findings from the experimentations revealed that the increase in gas velocity leads to decrease the mixing index inside the riser. Moreover, the solid holdup found more in abrupt riser than smooth riser at the constant gas velocity. Despite the more experimental investigations, the findings with CFD simulations revealed that the MP-PIC approach, which was combined with different drag models could be more effective for the practical (industrial) design of CFB riser. Well agreement was found between the simulation and experimental outputs. The simulation work was compared with experimental data, which shows the good agreement (<4%).

The experimental and simulation study performed in this research study constitutes an easy-to-use with different drag coefficient. The proposed MP-PIC model is more effective for large particles fluidized bed, which can be helpful for further research on industrial gas-particle fluidized bed reactors. This study is expected to give throughout the analysis of CFB hydrodynamics with further exploration of overall fluidization.

Rectangular fluidised beds are commonly used in industry, e.g. circulating fluidised bed (CFB) boilers. Apparently, no one has tried to imagine rectangular fluidised beds by electrical capacitance tomography (ECT). The purpose of this paper is to design a rectangular ECT sensor to understand the behaviour of a rectangular CFB riser.

A rectangular sensor with eight electrodes is adopted to obtain the capacitance data. The sensitivity map is simulated to calculate the grey level of pixels for visualisation using the linear back‐projection algorithm.

Experiments showed that the position of the objects in the riser can be obviously indicated and the central region of the object(s) has significantly higher grey level than other regions in the images using the rectangular ECT sensor.

It has a limitation in providing a higher resolution image.

The results obtained by the rectangular ECT sensor show that it is promising to study the characteristics of flow non‐uniformity in the fast fluidisation regime of CFB.

Without using square and circular ECT sensors, this is the first time a rectangular ECT sensor has been developed to study the unique problems of the characteristics of flow non‐uniformity in a rectangular CFB riser.

In Turkey, dependence on foreign countries for energy is a problem which upsets all economic balances. Turkey’s biggest fossil energy source is lignite coal. Therefore, energy conversion of lignite in thermal plants, causing minimum environmental effect is extremely important. The basic problem in terms of the combustion technology is to improve the combustion technology that can burn the low-qualified fuels that do not have standard fuel features (lignite, peat, schist). The most suitable technology today for the efficient and clean combustion of nonstandard low-qualified fuels is the combustion at fluidized-bed technology. In this study, CO₂ emission that occurs during the combustion of Orhaneli coal that is one of our native low-qualified lignite, has been investigated according to the experimental study.

For this combustion experiment, laboratory-scaled circulating fluidized-bed (CFB) process that exists at TÜBITAK-MAM Energy Institute which has been designed and used before has been used. The effect of excess-air coefficient, combustion type and bed temperature to the greenhouse gas formation and CO₂ emission has been investigated experimentally. In terms of flue gas emissions, it has been detected that the decrease of the amount of CO₂ that has occurred has no positive effects on combustion efficiency, water vapor, SO₂, NO_x, CO and other gases which occur during deficient combustion must be thought as a whole and each reaction affects each other similar to complex reactions.

As a consequence of measuring CO₂ emissions over 10 minute periods, CO₂ emissions are 12.43 percent average, CO₂ decreases at different air coefficient values; Often form undesirable side reactions such as CO, NOx with back and forth reactions.

The importance of aerodynamic structure of the system, and the losses and leakages forming in the system has been observed experimental and affected parameters are evaluated.

The energy retrofit of the existing building stock, and specifically the thermal upgrading of the buildings’ envelopes, has been identified as a key action for both the decarbonisation of the built environment and the reduction in fuel poverty. When considering the energy retrofit of heritage buildings it is, however, important to recognise both the technical issues that this entails and the potential impact on their cultural value and the emotional responses to it. The purpose of this paper is to focus on the thermal upgrading of historic timber-framed buildings in the UK.

The paper begins by exploring the cultural significance of this form of building construction, before examining three case studies using both quantitative and qualitative methodologies.

The results show that whilst the application of energy retrofit actions to this emblematic typology may have limited success, the emotional connection of the buildings’ occupants often results in the work resulting in higher user satisfaction than would otherwise be expected.

Although limited in number, the three case studies provide an insight into the complex issues surrounding the low energy retrofit of historic timber-framed buildings. Further research into this area is encouraged.

The paper contains the monitoring of specific retrofit details, the results of which should inform future projects.

The review of the cultural significance of historic timber-frame buildings in the UK underlines the importance of the conservation and continuing survival of these buildings.

Previous heritage retrofit research in the UK has focussed on solid wall construction with little investigation into the issues surrounding the retrofit of historic timber-frame buildings. This paper explores this previously under-researched area. Additionally, this paper begins to explore the possible links between occupants’ emotional connection to historic buildings and their perceived levels of comfort.

While the literature contains a number of studies of ethical investment funds, relatively little is known about church investment processes and practices despite the significant role they have played in the development of the sector. This paper attempts to address this lacuna by studying the ethical investment programmes of two UK churches: the Methodist Church and the Church of England. The paper initially explores the relationship between the Judaeo‐Christian church and the development of the ethical investment movement. This history reveals an engagement both at the institutional and individual level that challenges the assumed sacred secular divide now commonplace within the literature and the more recent guardian‐advocate dichotomy. Second, the paper delineates the way in which the churches theologically conceptualise this engagement and describes how these values are proceduralised through the operation of the funds. The final section provides an immanent critique of church investments both at a performative and theological level. The aim of this concluding section is to engage with the churches in exploring the broader potential for the church in effecting social change.

This paper aims to examine the use of Cross-Functional Bridge (CFB) in dyadic relationships towards enhancing organisational performance. Prior research has flagged conflict in interfunctional relationships. Research on managing such conflict context is, however, limited.

Analysing 20 in-depth interviews conducted in UK financial services organisations, this study explains how the CFB is used to manage interfunctional relationship conflict and enhance performance.

This study underlines three core insights about intragroup working relationship: cultural and disciplinary differences and boundary fencing are core features of, and conflict drivers in, the accounting – marketing interface; CFB is a tool for analysing and managing these conflict drivers; and organisations that use this tool achieve improved organisational performance, an outcome that is enhanced and sustained through the team psychological enhancement factor of the conflict management strategy. Also, this study underlines the need to ensure a fit between conflict management strategy and conflict types.

This research has several limitations. It explores only accounting – marketing working relationship in UK financial services organisations. Also, it explores only relationship conflict and cultural and disciplinary diversity and boundary fencing factors. Finally, this study suggests a mediating influence of psychological well-being on the CFB – performance link, a conclusion that is based on a methodologically inadequate tool: causes and effects associations are better assessed quantitatively (Johnson and Onwuegbuzie, 2004).

The paper highlights insights for analysing and resolving conflicts towards harmonious dyadic relationships. Importantly, managers who use the flagged CFB tool would achieve psychological enhancement in team, and extendedly enhanced organisational performance. Managers are reminded of the need to adequately address the emotional substances in relationship conflicts, as failure to do this will lead to conflict escalation, transformation and negative performance.

The paper offers theory testing and theory building knowledge. The CFB insight is a major highlight, one that lays a brick for future development, especially concerning its modus operandi, motivators and how to maximize its performance value.

The purpose of this paper is to first present the key features of the fuzzy logic (FL) approach as a cost-effective technique in simulations of complex systems and then demonstrate the formulation and application of the method.

The FL approach is used as an alternative method of data handling, considering the complexity of analytical and numerical procedures and high costs of empirical experiments. The distance from gas distributor, the temperature and the voidage of the bed, flue gas velocity and the load of the boiler are the input parameters, whereas the overall heat transfer coefficient for the membrane walls constitutes the output. Five overlapping sigmoid and constant linguistic terms are used to describe the input and the output data, respectively. The Takagi–Sugeno inference engine and the weighted average defuzzification methods are applied to determine the fuzzy and crisp output value, respectively.

The performed FL model allows predicting the bed-to-wall heat transfer coefficient in a large-scale 670 t/h circulating fluidized bed (CFB) boiler. The local heat transfer coefficients evaluated using the developed model are in very good agreement with the data obtained in complementary investigations.

The performed model constitutes an easy-to-use and functional tool. The new approach can be helpful for further research on the bed-to-wall heat transfer coefficient in the CFB units.

To understand the specificities of Cash-flow bullwhip in the context of major crises similar to that of COVID-19, to identify its financial impacts on the Moroccan FMCG companies, to establish the profile of the companies most affected by this CFB and finally to propose internal control mechanisms that should be put in place to mitigate the effects of Cash flow Bullwhip in such a context.

The authors chose to conduct descriptive research on companies operating in the fast-moving consumer goods sector in Morocco. For this purpose, a survey was conducted on a target population during the period from December 2020 to March 2021. To answer the different research questions, a multiple correspondence analysis (MCA) has been conducted on the 21 variables obtained from the survey questions.

Small and medium-sized companies are those that have been the most financially impacted. Indeed, the instability of the cash flow conversion cycle increased their working capital requirements and limited their self-financing capacity. To face this situation, those companies used alternative means to finance their operational activity by using their equities or bank loans.

Due to the originality of the COVID 19 context, this study gives a different angle of view to analyze the cash flow bullwhip and its implications on the financial health of companies.

The use of various forms of cooperative sales promotions such as intracompany and intercompany multibrand promotions is on the ascendance, particularly among manufacturers and marketers of frequently purchased packaged consumer products. This article provides an overview of various forms of cooperative sales promotions, objectives that firms strive to realize through cooperative sales promotions, and other issues. In addition, from the standpoint of improving marketing productivity, the need for greater focus on the consumer franchise building potential of various sales promotion tools is highlighted.

The Chinese family business (CFB) is one of the most enduring and prolific organizational forms in human history. The CFB is an alternative to a modernistic organization and has been understudied in the post‐modern organizational theory literature. Compares a pre‐modern CFB transplanted to the USA with the modernistic Toyota model of greenfield start‐ups.