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To introduce a novel numerical calculation procedure for periodically fully developed heat and fluid flow, which can treat three‐dimensional velocity and temperature fields, using a two‐dimensional storage.

The three‐dimensional Navier‐Stokes equation and energy equation have been transformed into quasi‐three‐dimensional forms. An appropriate set of explicit periodic boundary conditions have been obtained for thermally fully developed flow through a general three‐dimensional periodic structure, exploiting the volume averaging theory.

The proposed numerical procedure has been found inexpensive and efficient. Its validity has been proved by comparing the results obtained for a bank of long cylinders in yaw against available experimental data.

Since no explicit sets of periodic boundary conditions of this kind have been reported before, they will be exploited by researchers and practitioners interested in efficient numerical computations of three‐dimensional periodic heat and fluid flows.

To develop an effective and reliable procedure for the calculation of heat fluxes from the measured temperatures in experimental tests of impingement water cooling.

An inverse heat transfer analysis procedure is developed and implemented into a 2D finite element program. In this method, the least‐squares technique, sequential function specification and regularization are used. Simplifications in the sensitivity matrix calculation and iterative procedures are introduced. The triangular and impulse‐like profiles of heat fluxes simulating practical conditions of impingement water cooling are used to investigate the accuracy and stability of the proposed inverse procedure. The developed program is then used to determine the heat flux during impingement water cooling.

A hybrid procedure is developed in which inverse calculations are conducted with a computation window. This procedure may be used as a whole time domain method or become a periodically sequential or real sequential method by adjusting the sequential steps.

Parametric study and application show that the developed method is effective and reliable and that inverse analysis may obtain the heat flux with an acceptable level of accuracy.

Computer programs were developed based on the finite element method and the charge simulation method for the calculation of three dimensional electric fields in high voltage engineering. A brief description of the applied methods with respect to the special requirements of high voltage engineering is presented. In order to use the specific advantages of the finite element method and the charge simulation method, two procedures combining both methods are proposed: an iterative method and a direct method. For the calculation of three dimensional problems without symmetry the iterative procedure has the advantage that the coupling program is small compared with the field calculation programs and no major changes in these programs are necessary.

Sustainability encapsulates economic, environmental and societal domains. In order to conform to these domains, the efficiency of maintenance and repair of heritage buildings is no exception. Emergently, environmental considerations for sustainable heritage buildings repair have become increasingly important. The purpose of this paper is to present a decision-making process based on “Green Maintenance Model” – an appraisal approach based on life cycle assessment (LCA) of paint repair options for heritage buildings.

Calculation procedures of Green Maintenance model within selected boundaries of LCA enable evaluation of carbon emissions, in terms of embodied carbon expenditure, expended from paint repair for heritage buildings during maintenance phase.

“Green Maintenance” model could be understood as a carbon LCA of paint repair and has been recognized in reducing carbon emissions. Significantly, the model underpins decision-making for repair options for heritage buildings.

It must be emphasized that the calculation procedures of Green Maintenance model is not limited to heritage buildings and can be applied to any repair types, materials used and building forms. More importantly, this model practically supports environmentally focused conservation and promotes sustainable repair approach.

The implementation of Green Maintenance model highlights the efficiency of repairs options that may be adopted.

Green Maintenance shows that generated environmental maintenance impact from repair options relays the “true” embodied carbon expenditure contextualized within the longevity of repair and its embodied carbon. This will consequently allow rationale in appraisal of repair options.

In this work, a new two-phase version of the finite element-based Artificial Compressibility (AC) Characteristic-Based Split (CBS) algorithm is developed and applied for the first time to heat and mass transfer phenomena in porous media with associated phase change. The purpose of this study is to provide an alternative for the theoretical analysis and numerical simulation of multiphase transport phenomena in porous media. Traditionally, the more complex Separate Flow Model was used in which the vapour and liquid phases were considered as distinct fluids and mathematically described by the conservation laws for each phase separately, resulting in a large number of governing equations.

Even though the adopted mathematical model presents analogies with the conventional multicomponent mixture flow model, it is characterized by a considerable reduction in the number of the differential equations for the primary variables. The fixed-grid numerical formulation can be applied to the resolution of general problems that may simultaneously include a superheated vapour region, a two-phase zone and a sub-cooled liquid region in a single physical domain with irregular and moving phase interfaces in between. The local thermal non-equilibrium model is introduced to consider the heat exchange between fluid and solid within the porous matrix.

The numerical model is verified considering the transport phenomena in a homogenous and isotropic porous medium in which water is injected from one side and heated from the other side, where it leaves the computational domain in a superheated vapour state. Dominant forces are represented by capillary interactions and two-phase heat conduction. The obtained results have been compared with the numerical data available in the scientific literature.

The present algorithm provides a powerful routine tool for the numerical modelling of complex two-phase transport processes in porous media.

For the first time, the stabilized AC-CBS scheme is applied to the resolution of compressible viscous flow transport in porous materials with associated phase change. A properly stabilized matrix inversion-free procedure employs an adaptive local time step that allows acceleration of the solution process even in the presence of large source terms and low diffusion coefficients values (near the phase change point).

The purpose of this paper is to present an innovative approach for the development of a methodology to systematically assess the economic performance and for the assessment of the economic sustainability of a building, through the calculation of an economic sustainability index, within the sustainability framework according to the rules defined in EN 16627.

The methodology follows the principle of modularity, where aspects and impacts that influence the economic performance of the building during the phases of its life cycle are assigned to levels. It presents a model based on the construction costs of the building. The methodology in centered in the before use phase and restricted to residential buildings.

Definition of a model for assessing the economic performance and calculation of an economic sustainability index.

The methodology is focused only in the before use phase of the buildings, assuming they have the same functional equivalent. It can be expanded to include the other phases of the building life cycle.

The developed methodology will allow the selection of construction procedures, based on economic sustainability, contributing to more rational and support decisions.

Contributing to a more sustainable society.

The European framework of EN 15643 and EN 16627 for the assessment of building sustainability is new and, as such, not implemented in most practical tools. Also, economic sustainability is not usually considered in detail in existing models. This paper presents a methodology following the framework and, simultaneously, possible to integrate in existing approaches.

To provide information on the distribution of oil deposition inside the pipe conducting oil mist used for lubricating purposes and to show resulting variations of oil/air ratio.

The model of an industrial pipeline has been assembled ranging more than 100 m away from the oil mist source, equipped with devices collecting oil deposited inside the pipes. Other tests were performed in stands constructed as parts of pipes coiled in helical form. Long time experiments with continuous oil mist flow enabled to achieve calculable results.

The quantitative results obtained in experimental investigation on the reduction of oil/air ratio in an oil mist header system show that considerable differences of the oil/air ratio may be observed in a typical long pipeline. Possible consequences of oil deficiency on lubrication of remote mechanisms are presented in the case study. Results of tests are shown in diagrams and tables. These results may be useful for correction of design calculations procedures.

Tests have been made on the basis of one kind of the oil atomized in typical condition and conveyed with steady flow through the piping of rather simple geometry. However, there are other factors affecting oil droplets deposition and the most influencing are probably: the flow velocity/pipe diameter factor, oil atomization characteristics and the geometry of the oil mist piping.

The research has shown dramatic decrease of oil content in the long distance systems that may result in poor lubrication of remote mechanisms or over lubrication of those located close to the oil mist generator. It should be taken on account in calculation of oil mist demand to particular lubrication points.

Presented tests have been carried in the scale and flow parameters very close to those applied in industry. Thus, the results are reliable and could be very useful both for designers and the practitioners of centralized oil mist systems.

The purpose of this paper is to propose a method of determining the transient temperature of the inner surface of thick-walled elements. The method can be used to determine thermal stresses in pressure elements.

An inverse marching method is proposed to determine the transient temperature of the thick-walled element inner surface with high accuracy.

Initially, the inverse method was validated computationally. The comparison between the temperatures obtained from the solution for the direct heat conduction problem and the results obtained by means of the proposed inverse method is very satisfactory. Subsequently, the presented method was validated using experimental data. The results obtained from the inverse calculations also gave good results.

The advantage of the method is the possibility of determining the heat transfer coefficient at a point on the exposed surface based on the local temperature distribution measured on the insulated outer surface. The heat transfer coefficient determined experimentally can be used to calculate thermal stresses in elements with a complex shape. The proposed method can be used in online computer systems to monitor temperature and thermal stresses in thick-walled pressure components because the computing time is very short.

This study aims to present compatible computational fluid dynamics procedure for calculation of incompressible three‐dimensional time‐dependent flow with complicated free surface deformation. A computer software is developed and validated using a variety of academic test cases.

Two fluids are modeled as a single continuum with a fluid property jump at the interface by solving a scalar transport equation for volume fraction. In conjunction, the conservation equations for mass and momentum are solved using fractional step method. Here, a finite volume discretisation and colocated arrangement are used.

The developed code results in accurate simulation of interfacial flows, e.g. Rayleigh‐Taylor instability, sloshing and dambreaking problems. All results are in good concordance with experimental data especially when there are two phases with high density ratio.

Turbulence, which has great importance in a wide variety of real world phenomena, is not considered in the present formulation and left for future researches.

Here, an integrated numerical simulation for transient interfacial flows is presented. In this way, the pressure integral term in Navier‐Stokes equation is discretised based on a newly developed interpolation which results in non‐oscillative velocity field especially in free surface.

This paper presents two numerical methods, which will be able to predict the temperature distribution in the thin moving conducting sheet, which is caused by the eddy‐current losses in transverse flux inductive heating devices (TFIH). The first method is based on a finite element calculation, while the second one is based on a circuit approach. The main aim of this paper is the validation of the circuit model by comparison with the more accurate and sophisticate finite element model. In addition, the results of both numerical models have also been compared with those obtained by experimental measurements.