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This paper explores innovative manufacturing processes, which can be used to manufacture the national musical instrument of Trinidad and Tobago, the Musical Steel Drum or Steel Pan. The main manufacturing process used today is the manual hand‐forming technique. In order to achieve more consistent and deeper formed components while maintaining the high quality of the instrument, it is proposed that the Marforming process and the Flow‐forming process, and adaptation of the Spinforming process, be used more frequently in the future to replace the traditional Hand‐forming method. In the traditional Spinforming technique material is pushed from the outer circumference of the metal disc to the center in progressive passes of the former. This results in a thinning of the outer region of the formed component with thickening of the center, however the opposite is required for the musical steel drum and by adapting the process the required strain distributions were achieved. Evaluation took the form of strain analyses of pre‐formed steel drums and visual inspection of the quality of the surface finish. It was found that the Marformed components had the smallest range of strain values while the Spinformed components had the largest range.

For internal flows with small values of the Reynolds number, there is often at a considerable distance from the pipe inlet cross-section a change of the flow form from laminar to turbulent. To describe this phenomenon of laminar-turbulent transition in the pipe, also parallel-plate channel flow, a modified algebraic intermittency model was used. The original model for bypass transition developed by S. Kubacki and E. Dick was designed for simulating bypass transition in turbomachinery.

A modification of mentioned model was proposed. Modified model is suitable for simulating internal flows in pipes and parallel-plate channels. Implementation of the modified model was made using the OpenFOAM framework. Values of several constants of the original model were modified.

For selected Reynolds numbers and turbulence intensities (Tu), localization of laminar breakdown and fully turbulent flow was presented. Results obtained in this work were compared with corresponding experimental results available in the literature. It is particularly worth noting that asymptotic values of wall shear stress in flow channels and asymptotic values of axis velocity obtained during simulations are similar to related experimental and theoretical results.

The modified model allows precision numerical simulation in the area of transitional flow between laminar, intermittent and turbulent flows in pipes and parallel-plate channels. Proposed modified algebraic intermittency model presented in this work is described by a set of two additional partial differential equations corresponding with k-omega turbulence model presented by Wilcox (Wilcox, 2006).

The special structure of the vortex pump contributes to its complex internal flow pattern. A type of horizontal 150WX-200-20 vortex pump is taken as a research subject to deeply study the progression and distribution of flow pattern in its channel. To explain the mechanism of flow in this pump, numerical analysis of the whole flow and experiment have been conducted.

The authors studied and analyzed the distribution and evolution of flow pattern under different flow, such as circulating-flow, through-flow and other forms. Finally, a model of flow pattern in the vortex pump has been built, which has more perfectly fit the reality.

They are through-flow affected by circulating-flow, main and subsidiary circulating-flow, vortices between vanes and other vortices (or liquid impingement) in volute. Entering the pump, part of the flow stays in vanes and turn into vortices while the other goes into the front chamber. The flow that runs into the front chamber will be divided into two parts. One part will be collected by viscosity into a vortex rope when it passing through the interface between the impeller and the vaneless chamber, which closely relates to the circulating-flow, and the rest directly goes out of the field through the diffuser. Besides, a fraction of circulating-flow joins the through-flow when it goes through the section V and leaves the pump.

The research results build a theoretical foundation for working out the flow mechanism of the vortex pump, improving its efficiency and optimizing its hydraulic design.

Having read previous literature about vortex pump, we noticed that mechanisms of circulating flow and its relationship with energy transition remain unclear yet. However, this mechanism, which should be clarified, significantly influences the pump’s efficiency. To comply with the aim of investigating it, the 150WX-200-20 type pump is selected as study object in our present work.

Numerical simulation is conducted to formulate interactions between flow rate and geometric parameters of circulating flow with certain types of blade while experiments on inner flow are served as a witness to provide experimental confirmation of numerical results. Based on these, we coupled some parameters with the pump’s external performance to study their internal connections.

It is concluded that separatrix between circulating flow and other turbulent forms is not that clear under low flow rate. With flow increases, hydraulic losses coming of it will be dominant within the front chamber. Besides, we analogized circulating flow to vortices so as to make a quantitative analysis on its progressive evolution with changing flow, and vortices speaking for circulating flow can be divided into two groups. One is called main circulating flow vortex (hereinafter referred to as MCFV), which occurs all the time while subsidiary circulating flow vortices (hereinafter referred to as SCFV) appear in certain conditions. This context discusses the primary phase of our work with intent to follow up further with circulating flow characterized by vortices (hereinafter referred to as CFV). We confirmed that MCFV Vortex 1 (Vor1) directly influences the efficiency while SCFVs only play helping. As the flow goes to the given working condition, fluids in this pump tend to be steady with the size of CFVs getting larger and their shape being regular. Meanwhile, for MCFV Vor2 and Vor4, their geometric parameters are the key factors for efficiency. When CFVs become steady, they absorb other vortices nearby, as they have higher viscosity with the efficiency reaching its maximum.

The research results explore a new way to measure the circulating flow and help work out the causation of this flow pattern, which may be used to improve the vortex pump’s efficiency.

To provide a theoretical model of the dynamics of intellectual capital creation in regional clusters and in inter‐organizational networks. The model has been constructed on the basis of earlier studies, especially system's theoretical interpretation of organizations as knowledge systems, and then applied to the examination of a regional cluster operating in the mechanical wood processing industry in Eastern Finland. Intellectual capital in regional clusters is created by three main knowledge creation activities, each of which corresponds to a specific type of an inter‐organizational network. First, production networks aiming at efficiency and replication should function according to mechanistic system logic, focusing on the enactment of rules and regulations. Development networks aiming at continuous incremental development, on the other hand, are most successful when adhering to an organic mode, which emphasizes participation, tacit knowledge sharing, dialogue and mutual adjustments. Finally, innovation networks seeking to produce new intangible assets benefit from a dynamic systems model, where entropy and spontaneous knowledge flows form the basis for mastering radical change. Model should be applied to more cases to ascertain its validity. Provides means for understanding, assessing and managing creation of knowledge‐based value in inter‐organizational collaboration. Addresses three gaps in existing research: it focuses on regional intellectual capital; it examines the ways in which intellectual capital is created as a dynamic process; it provides means for understanding the future potential of a region.

The purpose of this paper is to encourage discussions regarding the existing approaches to globalization measurement (taking mainly the form of indices and rankings) and their shortcomings in terms of applicability to developing Global Studies curricula. Another aim is to propose an outline for the globalization measurement methodology that would take a systemic approach to revealing the global flows (both their direction and content) and networks, which will allow the multidimensionality in globalization measurement crucial for proposing and verifying formal explanations and hypotheses, as well as for developing globalization forecasts.

Several methodologies for globalization measurements are compared in the paper, among the most important are variations of the index compilation methodology, and methods of network analysis.

For Global Studies curricula, globalization measurement tools much more complex than indices are needed. A possible solution could lie in the analysis of country-to-country flows (and networks which these flows form), which appears much more data- and effort-consuming than the methodologies behind the index compilation, will allow the elaboration of a systemic vision of globalization and the interactions between its various aspects, which should necessarily underlie the Global Studies curricula.

The research concentrates upon the most widespread approaches to globalization measurements, such as the most widely recognized globalization indices, and the few attempts at country-to-country flows and networks measurement.

The paper's originality/value lies in proposing an outline for a new multidimensional approach to measuring globalization based upon country-to-country flows and networks.

The on-chip high-throughput mixing process is one of the main challenges in the preparation process in clinical diagnostics. Because of high laminar flow in micro-channel, the fluid should be disturbed by external force. This paper aims to study pulsed AC electrothermal flow and the multiphysic interaction between the fluid behavior, external electric field, temperature field and convection-diffusion field to generate perturbation effect inside the channel.

A set of numerical simulations were carried out by multiphysic interactions between the fluid behavior, external electric field, temperature field and convection-diffusion field to generate the pulsed AC electrothermal flow inside the channel. Behavior of electrode–electrolyte system is discussed using the electrical lumped circuit model.

Highly efficient temperature gradients are generated by applying pulsed electric potential over the electrodes; as a result, efficient secondary flows form inside the channel. The proposed method increases the interfacial contact area between the fluids and enhances the molecular diffusion transport phenomena. Maximum temperature rise of 4.1 K is observed in the gap between the electrodes for 0.08 S/m fluid medium, where the electric field is much stronger than elsewhere. Velocity field and concentration analysis reveal high performance perturbation effects for the mixing process. The periodic stretching and folding effects increase the interfacial contact area between the fluids by using pulsed AC electrothermal flow. Based on the results, 83 per cent mixing efficiency is achieved for 0.08 S/m fluid medium with a microchannel length of 400 µm. Both the mixing efficiency and generated temperature rise increase by increasing the fluid ionic strength.

The ability to generate low temperature rise is very important for AC electrothermally driven fluidic chips such as immunoassay chips. In the present research, a novel actuation mechanism has been proposed to generate AC electrothermal manipulation mechanism and enhance the mixing efficiency by using pulsed AC electrothermal flow.

The mesoscale structure (MS) has a significant impact on the mechanical performance of parts made by additive manufacturing (AM). This paper aims to explore the design and fabrication of force-flow guided reinforcement mesoscale structure (FFRMS) compared with the homogeneous mesoscale structure (HMS), which is inconsistent with the stress field for a given load condition. Some cases were presented to demonstrate the mechanical properties of FFRMS in terms of MS combined with quasi-isotropy and anisotropy.

The paper consists of four main sections: the first developed the concept of FFRMS design based on HMS, the second explored volume fraction control for the proportion of force-flow lines in terms of mechanical property requirement, and the third presented a sequence stacking theory and practical manufacturing process framework and the final sections provided some application case studies.

The main contributions of this study were the definition and development of the FFRMS concept, the application framework and the original case studies. As an example, a typical lug designed with the proposed FFRMS method was fabricated by three different AM processes. The test results showed that both the strength and stiffness of the specimens are improved greatly by using the FFRMS design method.

The superposition of HMS as the basement and force-flow as an indication of the stiffener, leading to a heterogeneous structure, which exhibits more efficient and diversified means compared with the traditional way of increasing the HMS density merely.

This paper aims to conduct the optimization of the multi-stage gas turbine with the effect of the cooling air injection based on the adjoint method.

Continuous adjoint method is combined with the S2 surface code.

The optimization of the stagger angles, stacking lines and the passage can improve the attack angles and restrain the development of the boundary, reducing the secondary flow loss caused by the cooling air injection.

The aerodynamic performance of the gas turbine can be improved via the optimization of blade and passage based on the adjoint method.

The results of the first study on the adjoint method applied to the S2 surface through flow calculation including the cooling air effect are presented.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics, and publications of other similar research bodies as issued