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The purpose of this paper is to describe the development and application of a numerical model for analysis of flow boiling phenomena and heat transfer.

For flow boiling processes, the fluid and vapour flow regimes in connection with the conjugate heat and mass transfer problem for specimen quenching through the entire boiling curve is modelled. Vaporisation and recondensation, the vapour fraction distribution and vapour movement with respect to the liquid are considered in the calculation of the two‐phase flow and heat transfer process. The derived flow boiling model is based on a mixture model and bubble crowding model approach for two‐phase flow. In addition to the conventional mixture model formulation, here special model implementations have been incorporated that describe: the vapour formation at the superheated solid‐liquid interface, the recondensation process of vapour at the subcooled vapour‐liquid interface, the mass transfer rate in the different boiling phases and the microconvection effect in the nucleate boiling phase resulting from bubble growth and detachment.

The model prediction results are compared with experimental data for quenching of a circular cylinder, showing good agreement in boiling state and heat transfer coefficient distribution. Simulation and experiments lead to a better understanding of the interaction of incident flow in the boiling state and the resulting heat transfer.

Fluid temperatures in the range of 300‐353 K and specimen wall temperatures up to 1,000 K are considered.

Flow boiling is an efficient heat transfer process occurring in several technical applications. Application background of the model development is in quenching of complex metallic specimen geometries in liquids subject to fast changing heat fluxes.

A general model for the complex two‐phase boiling heat transfer at high wall temperatures and fast flow conditions that can be used in engineering applications does not yet exist. The results provide detailed information describing the non‐uniform phase change during the complete quenching process from film boiling to pure convection.

The purpose of this paper is to add a process perspective to the literature on repatriate knowledge transfer (RKT) and to understand how the knowledge transfer process unfolds in the repatriation context. Thus, this qualitative study uses existing knowledge transfer process models to assess their applicability to the context of repatriation and explain the micro-processes during RKT.

To provide a rich understanding of these processes from the repatriate perspective, critical incidents reported by 29 German and US American repatriates were content-analyzed.

The findings are summarized in a proposed RKT process model, which describes the roles and knowledge transfer-related activities of repatriates, recipients and supervisors as well as their interaction during four transfer phases: assessment, initiation, execution and evaluation.

The experiences of repatriates from different geographic areas as well as the perspectives of knowledge recipients and supervisors were not studied but should be included in future research. In addition, future research could test the applicability of the identified micro-processes to different knowledge transfer contexts.

Managers can use the findings to facilitate the RKT process more effectively because the type of organizational support offered can be aligned with the changing needs of repatriates, recipients and supervisors during the four identified phases.

This is the first study that takes a process perspective to understand RKT. The integration of the current findings with the existing literature can enable a more nuanced view on RKT.

The purpose of this paper is to investigate the effects of gravity on the heat transfer behavior of the two-phase flow of water undergoing phase change. Most of the earlier studies of convective boiling considered systems where the gravity is neglected. In contrast, the authors investigated systems where the gravity is considered. The heat transfer characteristics of water during its evaporation in microchannel heat sink are studied for different channel inclinations.

Computational fluid dynamics software ANSYS Fluent is used for the computational study. The volume of fluids multiphase method available in the package is used to capture the vapor–liquid interface. Heat transfer studies are carried out for a rectangular microchannel having a characteristic dimension of 825 µm at different inclinations, which varied from −90° (vertically downward) to 90° (vertically upward). During each simulation, the vapor quality is set at the inlet. Uniform heat flux of 250 kW/m² is applied at the bottom wall of the channel in all orientations of the channel, keeping the upper wall insulated.

As compared to horizontal configuration, a significant increase in the values of heat transfer coefficient during the fluid flow in inclined microchannels is noticed. It is observed that the Nusselt number for the vertically upward (+90°) and horizontal (0°) configuration are similar and that for the 45° upward configuration exceeds other configurations. It is also observed that the heat transfer performance becomes lower in downward configurations; nearly 40-50 per cent drop in average Nusselt number is observed for a mass flux of 250 kg m^-2 s^-1 with respect to 45° inclined microchannel. This behavior can be attributed to the gravitational effect on the two-phase flow because of which the vapor phase being less dense moves away from the heated wall, whereas the primary phase being heavier moves towards the heated wall of the channel. Also, the conductivity of the liquid being higher than the vapor phase, as well as the aperture of the liquid being small during this process, its velocity increases resulting in the augmentation of heat transfer.

User-defined-functions for the mass and energy source terms have been written in C code and hooked in ANSYS Fluent to incorporate the phase change mechanism during the evaporation of water.

This paper aims to develop a procedure for preparing production transfers based on risk management principles. The procedure should help companies reduce the amount of supply chain disruptions during transfers and achieve their outsourcing/offshoring objectives.

The procedure was developed during a three-year Design Science study. First, a literature review and case studies were conducted to frame the research problem. Second, a preliminary procedure was developed based on preventive risk mitigation actions from the production transfer literature. Third, the procedure was implemented during an electronics-offshoring case and refined during workshops with the sender and receiver’s transfer personnel. Fourth, during a seminar, transfer practitioners verified the procedure by applying it to outsourcing/offshoring cases with which they had experience.

Most of the preventive actions were evaluated as relevant for the transfers the procedure was applied to, regardless of industry and relocation type. Moreover, the electronics-offshoring case showed that the success of a production transfer not only depends on the physical, knowledge and supply chain transfers, as presented in earlier research, but also on the administrative transfer and on the organisation, project and quality management actions. This paper also attempts to enhance the production transfer literature by clarifying transfer risk management.

The procedure can be used during the production transfer phase as a preparation procedure. Moreover, it informs the decision-making process during the relocation-decision and supplier-selection phases.

To the authors’ knowledge, this is the first production-transfer-preparation procedure based on risk management principles.

A combination of highly conductive porous media and nanofluids is an efficient way for improving thermal performance of relevant applications. For precisely predicting the flow and thermal transport of nanofluids in porous media, the purpose of this paper is to explore the inter-phase coupling numerical methods.

Based on the lattice Boltzmann (LB) method, this study combines the convective flow, non-equilibrium thermal transport and phase interactions of nanofluids in porous matrix and proposes a new multi-phase LB model. The micro-scale momentum and heat interactions are especially analyzed for nanoparticles, base fluid and solid matrix. A set of three-phase LB equations for the flow/thermal coupling of base fluid, nanoparticles and solid matrix is established.

Distributions of nanoparticles, velocities for nanoparticles and the base fluid, temperatures for three phases and interaction forces are analyzed in detail. Influences of parameters on the nanofluid convection in the porous matrix are examined. Thermal resistance of nanofluid convective transport in porous structures are comprehensively discussed with the models of multi-phases. Results show that the Rayleigh number and the Darcy number have significant influences on the convective characteristics. The result with the three-phase model is mildly larger than that with the local thermal non-equilibrium model.

This paper first creates the multi-phase theoretical model for the complex coupling process of nanofluids in porous structures, which is useful for researchers and technicians in fields of thermal science and computational fluid dynamics.

The purpose of this study is to investigate the applicability of volume average which is extensively used for analyzing the heat and fluid flow (both for single-phase and solid/liquid-phase change) in a closed cell porous medium numerically.

Heat conduction equations for the solid frame and fluid (or phase change material) are solved for pore scale and volume average approaches. The study mainly focuses on the effect of porosity and the number of porous media unit cell on the agreement between the results of the pore scale and volume average approaches.

It is observed for the lowest porosity values such as 0.3 and the number of porous media unit cell as 4 in heat transfer direction, the results between two approaches may be questionable for the single-phase fluid. By increasing the number of porous media unit cell in heat transfer direction, the agreement between two approaches becomes better. In general, for high porosity values (such as 0.9) the agreement between the results of two approaches is in the acceptable range both for single-phase and solid/liquid-phase change. Two charts on the applicability of volume average method for single-phase and solid/liquid-phase change are presented.

The authors’ literature survey shows that it is the first time the applicability of volume average which is extensively used for analyzing the heat and fluid flow in a closed cell porous medium is investigated numerically.

The purpose of this paper is to propose a method for the transfer of knowledge and skills in project management (PM) based on techniques in knowledge management (KM).

The literature contains studies on methods to extract experiential knowledge in PM, but few studies exist that focus on methods to convert extracted knowledge into practical knowledge and transfer it to learners. This research proposes a model of PM skills transfer management, which consists of a PM knowledge extraction phase, PM knowledge recognition phase, practical knowledge transfer phase, and practical knowledge evaluation phase, and examines the model's effectiveness.

Through multi‐agent simulation (MAS), expert communities for knowledge extraction can be vitalized. A PM skills transfer management maturity model (PMST3M) was proposed that is capable of evaluating PM skills transfer management.

The present work could have considered KSM in‐depth with a view to adding value to the virtualization of community of PM experts.

The paper presents a detailed critique of a knowledge‐management‐based process of transferring PM skills.

The purpose of the paper is to find out the knowledge requirements and its effect on both onsite and offshore project work division for development, re-engineering and maintenance projects in Indian outsourcing software industry in different phases of software development.

This study employs an expert interview approach in Indian software industry to find out knowledge requirement for project execution and division of work between onsite and offshore locations. The requisite data were collected through expert interviews and direct observations.

The study found that the development projects require higher level of domain, strategic, business process and operation process knowledge in comparison to re-engineering and maintenance projects. So there is a need of higher onsite presence in development projects. The maintenance work is taken up at the offshore location in a phase-wise manner.

The implication of the study is in the development of a broad framework of knowledge requirements and work division in on-shore and offshore locations for Indian software outsourcing projects. As the study is based on expert opinion in the context of India, it cannot be generalized for outsourcing scenarios elsewhere.

The software project manager can use the findings to get more insight into the project and divide the software team between onsite and offshore location.

The study is novel, as there is little attempt at finding the knowledge requirement to execute various kinds of business software development in outsourcing environment in the context of India.

The purpose of this study is to validate whether the local thermal equilibrium for unsteady state is an appropriate assumption for the porous media with closed pores. It also compares the transient temperatures between the pore scale and volume averaged approaches to prove that the volume averaged method is an appropriate technique for the heat transfer in closed-cell porous media. The interfacial heat transfer coefficient for the closed-cell porous media is also discussed in details.

The governing equations for the pore scale and continuum domains are given. They are solved numerically for the pore scale and volume-averaged domains. The results are compared and discussion was done. The performed discussions and explanations are supported with figure and graphics.

A local thermal non-equilibrium exits for the closed-cell porous media in which voids are filled with water during the unsteady heat transfer process. Local thermal non-equilibrium condition exists in the cells under high temperature gradient and it disappears when the heat transfer process becomes steady-state. Although a local thermal equilibrium exists in the porous media in which the voids are filled with air, a finite value for heat transfer coefficient is found. The thermal diffusivity of air and solid phase are close to each other and hence a local thermal equilibrium exists.

The study is done only for the closed-cell porous media and for Rayleigh number till 10⁵. Two common working fluids as water and air are considered.

There are many applications of porous media with closed pores particularly in the industry, such as the closed-cell metal foam or the closed cells in porous materials such as foods and plastic-based insulation material. The obtained results are important for transient heat transfer in closed-cell porous materials.

The obtained results are important from the transient application of heat transfer in the closed-cell material existing in nature and industry.

The authors’ literature survey shows that it is the first time the closed-cell porous media is discussed from local thermal non-equilibrium point of view and it is proved that the local thermal non-equilibrium can exist in the closed-cell porous media. Hence, two equations as solid and fluid equations should be used for unsteady heat transfer in a closed-cell porous medium.