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The purpose of this paper is to examine the modeling of simultaneous heat and mass transfer under dehumidifying conditions. Moist air cooling in tube‐fin exchangers is investigated using a finite element technique.

The model requires the solution of a conjugate problem, since interface temperatures must be calculated at the same time as temperature distributions in adjacent fluid and solid regions. The energy equation is solved in the whole domain, including the solid region, and the latent heat flux on the surfaces where condensation takes place is taken into account by means of an additional internal boundary condition.

Thermal performances for different Reynolds numbers of a typical two‐row tube‐fin exchanger are numerically analysed, for both in‐line and staggered arrangements of tubes. The results justify the great importance that the ratio between latent and overall rates of heat transfer has in the design of compact heat exchangers.

In this work, the capabilities of the proposed methodology to deal with industrial applications in the field of compact exchangers are outlined.

The paper presents an effective approach to the solution of conjugate conduction and convection problems with simultaneous heat and mass transfer. The formulation is completely general, even if the finite element method is used in the calculations.

By neglecting the influence of tubes, this paper adopts a simplified two‐dimensional approach to deal with laminar convection of air through wavy finned‐tube exchangers. Pressure drop and heat transfer characteristics are investigated in the fully developed region of the flow channels between adjacent fins. The solutions are presented for several space ratios (height over length of a module) and two corrugation angles. They concern laminar flows both below and above the onset of the self‐sustained oscillations that precede the transition to turbulence. Fully developed velocity and thermal fields are computed by imposing anti‐periodic conditions at inlet/outlet sections of a single calculation cell. In the range of Reynolds numbers investigated, Nusselt numbers and friction factors first increase with space ratios (up to a value depending on the corrugation angle), then start decreasing with increasing space ratios.

Joint descriptions of both heat and mass transfer and thermodynamic aspects of air‐cooling applications cannot be easily found in the literature. Numerical analyses are a notable exception since suitable physical models and realistic boundary conditions are a prerequisite of accurate simulations. Thus, it is believed that the experience gained with numerical simulations might be of some help also to designers of air‐conditioning and drying systems. This paper seeks to address this issue.

In the text, the physical implications of governing equations and boundary conditions utilized in numerical simulations are extensively discussed. Particular attention is paid to the thermodynamically consistent definition of latent and sensible heat loads, and to the correct formulation of the heat and mass transfer analogy.

Comparisons of analytical and numerical results concerning forced flows of humid air over a cooled plate validate the assumptions made in numerical simulations, both for air‐conditioning applications (almost always characterized by low rates of mass convection) and drying applications (almost always characterized by high rates of mass convection).

Finally, with reference to the cold plate problem investigated here, the effects of the suction flow induced by condensation on the Nusselt number are quantified.

The purpose of this paper is to develop a simplified but accurate finite element procedure for the analysis of the conjugate conduction-convection heat transfer in cross-flow micro heat exchangers.

The velocity fields in single microchannels are calculated by solving the parabolised form of the momentum equations and later mapped onto the three-dimensional grid, corresponding to an appropriate portion of the micro heat exchanger, which is used for the solution of the energy equation in its elliptic form. To allow the use of finite elements elongated in the flow direction, layers of perpendicular microchannels can be meshed independently with grids that do not match at the common interface (domain decomposition).

An original and easy-to-implement method has been developed to deal with non-matching grids. Computed results show that increasing the number of microchannels per layer yields relative pressure drop increments that are larger than those displayed by the relative heat flow rates.

The simplified procedure requires the assumption of constant thermophysical properties. The adopted domain decomposition technique yields non-symmetric system matrices.

The procedure can be very useful in the design of cross-flow micro heat exchangers.

The finite element procedure described in the paper requires only limited computational resources for the analysis of the conjugate conduction-convection heat transfer in cross-flow micro heat exchangers with a large number of microchannels per layer.

This paper aims to present a comprehensive analysis of conjugate heat transfer phenomena occurring within the developing region of square ducts under both isothermal and isoflux boundary conditions. The study involves a rigorous numerical investigation, using advanced computational methods to simulate the complex heat exchange interactions between solid structures and surrounding fluid flows. The results of this analysis provide valuable insights into the heat transfer characteristics of such systems and contribute to a deeper understanding of fluid–thermal interactions in duct flows.

The manuscript outlines a detailed numerical methodology, combining computational fluid dynamics and finite element analysis, to accurately model the conjugate heat transfer process. This approach ensures both the thermal behaviour of the solid walls and the fluid flow dynamics are well captured.

The results presented in the manuscript reveal significant variations in heat transfer characteristics for isothermal and isoflux boundary conditions. These findings have implications for optimizing heat exchangers and enhancing thermal performance in various engineering applications.

The insights gained from this study have the potential to influence the design and optimization of heat exchange systems, contributing to advancements in energy efficiency and engineering practices.

The research introduces a novel approach to study conjugate heat transfer in square ducts, particularly focusing on the developing region. This unique perspective offers fresh insights into heat transfer mechanisms that were previously not thoroughly explored.

This study aims to investigate the effectiveness of integrated audit management and its impact on business sustainability for an emerging economy.

Drawing on the dynamic capability and contingency theory, the authors investigated the factors on integrated audit management implementation using a sample of 104 certified Malaysian manufacturing firms. The collected data has been analysed using the partial least squares through the structural equation modelling technique.

The findings have revealed that human resource capability, technological capability and quality capability have a robust influence on the importance of the internal audit process, which, in turn, leads to integrated audit management effectiveness towards the outcome of business sustainability. The results have also indicated the mediating effect of the internal audit process on the research model.

The contribution from the empirical findings will provide productive insights to help manufacturing firms devise an effective integrated internal audit management system to ensure business sustainability and increase competitiveness advantages for an emerging economy.

The concept of positional innovation – as one of the four innovation types of the Francis and Bessant’s “4P’s” model – is an effective product innovation strategy for producers of mature and credence goods as food products are. Despite the acknowledgement as one of the major industries worldwide, positional innovations about the food products are underexplored in the managerial literature. To fill this gap, this paper first develops a theoretical analysis of the concepts. Then, by adopting a case-study research methodology, it discloses the way a bakery small enterprise manages positional innovation. Theoretical and practical implications are finally introduced and discussed.

After a literature review about the role and the characteristics of the positional innovation, the paper presents a case study of definition and implementation of managerial actions and initiatives driven by positional innovation. The aim is not to report on an inductive study, but to use this example as a picture to clarify theory and show how the various conceptual issues may be operatively applied and provide more contextual insights.

It emerges how a small food enterprise manages positional innovation to survive and compete in the national and international markets; the positional innovation sources are tapped into culture, social responsibility, tradition and other territorial assets of tangible and intangible nature, effectively combined to innovate the product perception and/or the utility in a use context.

“Non-technological”, simple products, like food, are underexplored and rarely seen as relevant context to investigate along the strategic and innovation management literature. Nonetheless, positional innovation is a perspective that values and credits the innovation efforts of small food products, revealing interesting managerial concepts and inspiring entrepreneurs and managers for activating and sustaining new strategies of innovation for their businesses.

The paper adopts a simplified two‐dimensional approach to deal with convective heat and mass transfer in laminar flows of humid air through wavy finned‐tube exchangers. The computational domain is spatially periodic, with fully developed conditions prevailing at a certain distance from the inlet section. Both the entrance and the fully developed flow region are investigated. In the fully developed region, periodicities in the flow, temperature and mass concentration fields are taken into account. The approach is completely general, even if the finite element method is used for the discretizations. In the application section, velocity, temperature, and mass concentration fields are computed first. Then apparent friction factors, Nusselt numbers, Colburn factors for heat and mass transfer, and goodness factors are evaluated both in the entrance and in the fully developed region.

The purpose of this paper is twofold: to describe a relevant improvement to an in-house FEM procedure for the heat transfer analysis of cross-flow micro heat exchangers and to study the influence of microchannel cross-sectional geometry and solid wall thermal conductivity on the thermal performance of these microdevices.

The velocity field in each microchannel is calculated separately. Then the energy equation is solved in the whole computational domain. Domain decomposition and grids that do not match at the common interface are employed to make meshing more effective. Some flow maldistribution effects are taken into account.

The results show that larger thermal conductivities of the solid walls and rectangular cross-sectional geometries with higher aspect ratios allow the maximization of the total heat flow rate in the device. However, on the basis of the heat transfer per unit pumping power, the square cross-section could be the best option.

The value of the average viscosity is assumed to be different in different microchannels, but constant within each of the microchannels.

The procedure can represent a valuable tool for the design of cross-flow micro heat exchangers.

In spite of requiring limited computational resources, the improved procedure can take into account flow maldistribution effects stemming from non-uniform microchannel temperatures.

Despite the widespread attribution that stressful crucible experiences result in important individual developmental change within leaders, a deeper exploration of the mechanisms of that change is warranted. Likewise, literature linking the crucible and individual change to social and organizational considerations, including how organizations can plan for and sponsor institutionalized crucibles, is sparse. Thus, the intent of this chapter is to begin to synthesize the crucible, cognitive development, and stress literatures to show important linkages, risks, and outcomes, then provide a basic blueprint of planning considerations for organizations that desire to establish their own crucible events that target leader development.