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This paper presents a spectral multidomain method for solving the Navier‐Stokes equations in the vorticity‐stream function formulation. The algorithm is based on an extensive use of the influence matrix technique and so leads to a direct method without any iterative process. Numerical results concerning the Czochralski melt configuration are reported and compared with spectral monodomain solutions to show the advantage of the domain decomposition for such a problem which solution presents a singular behaviour.

The multi‐domain generalized differential quadrature method is applied in this paper to simulate the flows in Czochralski crystal growth. The effect of interface treatment on the numerical solution is studied through four types of interface approximations. The performance of those four interface approximations is validated by a benchmark problem suggested by Wheeler. It is demonstrated in this study that the multi‐domain GDQ approach is an efficient method which can obtain accurate numerical solutions by using very few grid points, and the overlapped interface approximation provides the most accurate numerical results.

A computational model is developed to describe convection in volatile liquids evaporating in capillary tubes. Experimental work has demonstrated the existence of such convective structures. The correlation between this convection and the phase change process has been experimentally established. Temperature distribution on the liquid‐vapour interface is considered in order to characterise the minimum of radial temperature gradient required to initiate and orientate Marangoni convection. Direct numerical simulation using finite volume approximation is used to investigate the heat and mass transfer in the liquid phase. The case of a capillary tube filled with a volatile liquid is investigated for various Marangoni numbers, to characterise heat and mass transfers under conditions close to realistic operating parameters. The simulation shows that a minimum irregularity in evaporative flux along the liquid‐vapour interface is necessary to trigger thermocapillary convection. The enhancement of heat and mass transfer by Marangoni convection is also investigated.

The interaction of a global model (GM) and a local (regional) model (LM) of heat flow is considered under the framework of so‐called “one‐way nesting”. In this framework, the GM is constructed in a large domain with coarse discretization in space and time, while the LM is set in a small subdomain with fine discretization.

The GM is solved first, and its results are then used via some boundary transfer operator (BTO) on the GM–LM interface in order to solve the LM. Past experience in various fields of application has shown that one has to be careful in the choice of BTO to be used on the GM–LM interface, since this choice affects both the stability and accuracy of the computational scheme. Here the problem is first theoretically analyzed for the linear heat equation, and stable BTOs are identified. Then numerical experiments are performed with one‐way nesting in a two‐dimensional channel for heat flow with and without radiation emission and linear reaction, using four different BTOs.

Among other conclusions, it is shown that the “negative Robin” BTO is unstable, whereas the Dirichlet, Neumann and “positive Robin” BTO are all stable. It is also shown that in terms of accuracy, the Neumann and “positive Robin” BTOs should be preferred over the Dirichlet BTO.

This study may be the first step in analyzing BTO accuracy and stability for more general atmospheric systems.

This study aims to show the importance of natural convection of supercritical fluid in an inclined cavity. The heat transfer performance of natural convection can be improved.

A model of an inclined cavity was set up to simulate the natural convection of supercritical fluid. The influence of inclined angles (30 to approximately 90°) and pressures (8 to approximately 12 MPa) are analyzed. To ascertain flow and heat transfer of supercritical fluid natural convection, this paper conducts a numerical investigation using the lattice Boltzmann method (LBM), which is proven to be precise and convenient.

The results show that the higher heat transfer performance can be obtained with an inclined angle of 30°. It is also presented that the heat transfer performance under pressure of 10 MPa is the best. In addition, common criterion number correlations of average Nusselt number are also fitted.

These study results can provide a theoretical reference for the study of heat transfer of supercritical fluid natural convection in engineering.

Hospital at Home (HAH) is a concept slowly expanding over time. At first this type of organization was used to accomplish low‐technical tasks. The main objective was to increase bed availability in hospitals for new patients. Nowadays, HAH structures are able to undertake more technical complex care such as (but not limited to) end‐of‐life care, chemotherapy and rehabilitation. The purpose of this paper is to propose a new methodology to make an unbiased economic comparison between HAH structures and traditional hospitalization.

This article accomplishes two main objectives: in the first part the authors propose a comprehensive literature review dealing with the comparison between traditional hospital and home care structures from an economic standpoint, showing that results are highly dependent on initial conditions of the study (patient health state, territory settings, bio‐medical parameters); in the second part the authors propose an unbiased economic comparison approach between health care provided in traditional hospital and home care network using formal modelling with Petri nets and discrete event simulation. As an example for the comparison a multi‐session treatment is proposed. Various scenarios are tested to ensure that results will be maintained even if initial conditions change. Relevant performance indicators used for comparison are economic costs from the point of view of the insurance and economic costs related to the consumption of resources.

It is found that HAHS can be used to control and improve patients flow on hospitals. Decisions about offering a multi‐session treatments at home must be taken, not only because of economic impacts on hospitals, but also because it follows strategic goals of the organization. This decision must be issued following a strategic analysis. Some important questions are: How should newly available beds be used in the hospital? Which territories will be covered? What is the best logistic strategy for delivering the medicines?

Comparing HAH with traditional hospitalization can provide useful information to healthcare authorities when deciding to create, or not, new HAH structures.