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The design of vacuum calibrators for the cooling of complex PVC profiles is central to the production of high quality extrudates. One important parameter governing cooling efficiency is the heat transfer coefficient at the interface between the stainless steel calibrator and the PVC extrudate, whose value is often taken as constant regardless of the extrusion velocity and the applied pressure vacuum. In this paper, a method is proposed to evaluate the variation of the heat transfer coefficient over the entire calibrator length. The idea is to use temperature measurements together with heat transfer simulation to derive a heat transfer correlation that can be used in practical design cases.

Presents a review on implementing finite element methods on supercomputers, workstations and PCs and gives main trends in hardware and software developments. An appendix included at the end of the paper presents a bibliography on the subjects retrospectively to 1985 and approximately 1,100 references are listed.

The purpose of this paper is to propose an adaptive refinement strategy based on a posteriori error estimate for the efficient simulation of free surface flows using discrete least squares meshless (DLSM) method.

A pressure projection method is employed to discretize the governing equations of mass and momentum conservation in a Lagrangian form. The semi‐discretized equations are then discretized in space using the DLSM method, in which the sum of squared residual of the governing equations and their boundary conditions are minimized with respect to the unknown nodal parameters.

Since the position of the free surface is of great significant in free surface problems, a posteriori error estimator which automatically associates higher error to the nodes near the free surface is proposed and used along with a node moving refinement strategy to simulate the free surface problems more efficiently. To test the ability and efficiency of the proposed adaptive simulation method, two test problems, namely dam break and evolution of a water bubble, are solved and the results are presented and compared to those of analytical and experimental results.

Error estimate and adaptive refinement have been mostly used in confined and steady‐state flow. Here in this paper, a new attempt has been made to use these concepts in moving boundary problem.

A semi‐implicit Taylor‐Galerkin/pressure‐correction algorithm of a transient finite element form is applied to analyse the flow instabilities that commonly arise during reverse‐roller coating. A mathematical model is derived to describe the solvent coating applied to the underside of the sheet, assuming that the lacquer is a Newtonian fluid and considering the flow between application roller and foil. Here, we have investigated the effects of temporal instabilities, caused by adjustment of nip‐gap width and foil‐position, extending our previous steady‐state analysis. Foil shifting is found to have a significant influence upon pressure and lift on the foil, drag on the roller, and free coating profiles. This would result in process instabilities, such as chatter and flow‐lines. In contrast, nip‐gap adjustment has no influence on the coating finish.

This article is concerned with the numerical simulation of a reverse roller‐coating process, which involves the computation of Newtonian viscous incompressible flows with free‐surfaces. A numerical scheme is applied of a transient finite element form, a semi‐implicit Taylor‐Galerkin/pressurecorrection algorithm. For free‐surface prediction, we use kinematic boundary adjustment with a mesh‐stretching algorithm. In the present work, an alloy sheet (foil) passes over a large roller and then a smaller applicator roller, which provides the in‐feed. In combination, the applicator roller, the foil and the fluid form part of the underside coating mechanism. The aim of this study is to investigate fundamental aspects of the process, to ultimately address typical coating instabilities. These may take the form of chatter and starvation. A uniform coating thickness is the desired objective. A mathematical model is derived to describe the solvent coating applied to the underside of the sheet, assuming that the lacquer is a Newtonian fluid. In particular, the work has concentrated on the flow patterns that result and a parameter sensitivity analysis covering the appropriate operating windows of applied conditions. Effects of independent variation in roll‐speed and foil‐speed are investigated, to find that maxima in pressure, lift and drag arise at the nip and are influenced in a linear fashion.

There are three purposes in this paper: to verify the importance of bi-directional fluid-structure interaction algorithm for centrifugal impeller designs; to study the relationship between the flow inside the impeller and the vibration of the blade; study the influence of material properties on flow field and vibration of centrifugal blades.

First, a bi-directional fluid-structure coupling finite element numerical model of the supersonic semi-open centrifugal impeller is established based on the Workbench platform. Then, the calculation results of impeller polytropic efficiency and stage total pressure ratio are compared with the experimental results from the available literature. Finally, the flow field and vibrational characteristics of 17-4PH (PHB), aluminum alloy (AAL) and carbon fiber-reinforced plastic (CFP) blades are compared under different operating conditions.

The results show that the flow fields performance and blade vibration influence each other. The flow fields performance and vibration resistance of CFP blades are higher than those of 17-4PH (PHB) and aluminum alloy (AAL) blades. At the design speed, compared with the PHB blades and AAL blades, the CFP blades deformation is reduced by 34.5% and 9%, the stress is reduced by 69.6% and 20% and the impeller pressure ratio is increased by 0.8% and 0.14%, respectively.

The importance of fluid-structure interaction to the aerodynamic and structural design of centrifugal impeller is revealed, and the superiority over composite materials in the application of centrifugal impeller is verified.

The purpose of this paper is to measure the apparent and complex viscosities of the zinc‐rich coatings derived from sodium silicate solution modified with aluminium chloride (AlCl₃), and then theoretically analyse the relation between viscosity behaviour and physiochemical mechanisms.

According to the different dosages of AlCl₃, five coatings were prepared. The apparent viscosities as functions of shear rate, time and temperature, complex viscosity with variations of temperature and heating rate of these coatings were measured using an AR500 rheometer.

Results showed that the zinc‐rich coatings possessed the typical shear thinning behaviour and the apparent viscosity increased with time until solidification. Complex results showed that the complex viscosity depended strongly on heating rate. Both apparent and complex viscosities initially decreased to minimum and then started to increase, while temperature was ramped from 0 to 70°C.

It is believed that there is no published literature about the apparent and complex viscosities of the zinc‐rich coatings from sodium silicate solution modified with AlCl₃. This paper presents the first attempt to obtain the rheological data of these zinc‐rich coatings.

In this chapter, we first show how the concept of competency, and management of or by competency, can be a factor in helping more people find employment, improve employability and develop competency, thus contributing to increased diversity in the workforce at every level of an organisation. We then examine a different part of the literature, more closely related to organisational learning, which finds that deviance and diversity can potentially boost competency. Subsequently, we look at diversity management first as an organisational competency, then as an individual competency. Concerning the reasons for the spread of management by competency and diversity management, we shall see that their respective advocates employ the same rhetoric of economic rationality, with both types of practice being justified by an objective change in the environment and, for this reason, presented as unavoidable and to some extent as simply “moving with the times”. In opposition to this supposed rationality as seen by companies, we will show that, in France, the two concepts of competency and diversity interact closely with institutional processes of mimetism, normalisation and coercion. In the final section, we shall look more closely at critical views of management by competency and diversity, as the criticisms of the two concepts are very similar and question their (possible) claims to be propelling society towards a fairer society.

Transport shapes the health of urban populations. It can support healthy behaviours such as participation in regular physical activity and access to community connection. Transport systems can also have major negative impacts on health. For example, through air pollution from fossil fuel-based modes of travel, the risk of injury and death from transport related collisions, and in the way sedentary modes of travelling can contribute to less physically active lifestyles.

This chapter considers the long-term impact of the pandemic on a series of well-researched transport-related health outcomes. It first describes the established connections between transport and health. It then considers the future implications of three potential pandemic-induced shifts: the increased uptake of working from home (WFH); decreased usage of public transport and increased interest in walking and cycling in the local neighbourhood. The impacts of these shifts on the transport-health nexus are then discussed, revealing both positive and negative outcomes. The authors conclude by providing policy recommendations to mitigate possible negative outcomes and strengthen the positive consequences into the future.