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The aim of this work is the development of a procedure able to model the highly irregular cellular structure of metallic foams on the basis of information obtained by X-ray tomographic analysis.

The geometric modelling is based on the feature “pore” characterized by an ellipsoidal shape. The data for the geometric parameters of the instances are obtained with a methodology which is driven by the pore volume distribution curve. This curve shows how much the cells, whose diameter belongs to a given dimensional range, contribute to the reduction of the total volume.

The presented methodology has been implemented into a CAD tool consisting of a Matlab routine identifying the instances of the feature “pore” and a CATIA's macro modelling the closed cells foam.

The presented methodology allows to obtain in an automatic way the CAD model of the complex structure of closed cell aluminium foam approximating by considerable accuracy both the density and the volume distribution of the real foams.

This study aims to generate different three-dimensional (3D) foam models using computer tomography (CT) scan and solid continuum techniques. The generated foam models were used to study deformation mechanism and the elastic-plastic behaviour with the existing experimental foam behaviour.

CT scan model was generated by combing 2D images of foam in MIMICS software. Afterwards, it was imported in ABAQUS/CAE software. However, solid continuum model was generated in ABAQUS/CAE software by using crushable foam properties. Then, the generated foam models were sets boundary conditions for a compression test.

CT scans capture the actual morphology of foam sample which may directly an image based finite element foam model. The sectional views of both the models were used to observe deformation mechanism on compression. The real compressive behaviour of foam was visualised in CT-Scan foam model. It was observed that CT-scan model was the more accurate modelling method than crushable foam model.

The internal structure of foam is very complex and difficult to analyse. Therefore, CT-scanning may be the accurate method for capturing the macro-level detailing of foam structure. A CT-scan foam model can be used for multiple times for mechanical analysis using a simulation software, which may reduce the manufacturing and the experimental cost and time.

As compared with homogeneous metals and alloys, cellular metals provide low density, high specific stiffness, high energy absorption and good damping, thus being interesting alternatives to employ as protection against shock and impact. Impact energy is dissipated through cell bending, buckling or fracture. The knowledge and computational modelling of the mechanical behaviour of metal foams structures is thus of great importance for real life applications. The purpose of this paper is to increase the knowledge of the differences in metallic hollow sphere structures' (MHSS) behaviour under dynamic loading, as compared with the corresponding behaviour under static loading and to determine the influence of inertia and loading rate.

Computational dynamical finite element analyses of representative volume elements (RVE) of MHSS have been performed considering varying loading rates. Partially bonded geometries are considered and the effect of the spheres' distribution is also taken into account.

The results of the numerical examples presented show that inertia plays an important role in the dynamic behaviour of this kind of energy‐absorbing structure. When compared with the corresponding values in the quasi‐static case, the effect of inertia makes the peak load higher. If the deformation rate is higher (greater than 1.39 m/s in the studied cases), the characteristic plateau usually present in compressed metal foams can vanish. For the geometries analysed, damage has a small influence on load‐deformation relations.

This paper presents and discusses differences between static and dynamic behaviour of partially bonded MHSS. There are few references in the literature covering this issue by means of numerical analysis.

HEAVY ATTENDANCES AT OUR FIRST CONVENTION. CORROSION TECHNOLOGY's first Convention can fairly be judged to have been an unqualified success. Of the 517 registered delegates, over 450 actually attended at the Central Hall, Westminster, and throughout the two days, when 13 papers were presented and discussed, the Hall seldom contained less than 300. Delegates included a fair sprinkling from overseas and the following countries were represented: Canada, Denmark, France, Germany, Holland, Italy, Norway, Portugal, Sweden, Switzerland, United States and the U.S.S.R.

The purpose of this paper is to present some new results about reflective cold protective clothing (i.e. those featuring metal coatings), and compare and contrast the data with other recent research work.

The authors used a thermal manikin and a guarded hot plate to determine the thermal resistance of different textile assemblies and garment featuring plasma-deposited metal-coated insulation and interlayers.

Depending on the exact approach, the authors show that metal coatings can increase the thermal resistance of textile assemblies by ∼30-75 per cent.

New data on reflective cold weather clothing show that metal coatings could be an important addition to cold weather clothing, especially those featuring high air permeability/optical porosity insulation. Plasma-deposited metal coatings cause the lowest increase in weight.

This paper provides new data about the efficacy, in terms of thermal resistance, of metal coatings for cold weather clothing.

The purpose of this paper is to clarify the relationship between dust deposition effects on the thermohydraulic performance of a metal foam heat exchanger.

The paper uses finite volume approximation to solve the two‐dimensional volume‐averaged form of governing equations through and around a metal foam‐covered tube bundle. Modified porosity, permeability, and form drag coefficient for a dusty foam layer are obtained through the application of a thermal resistance network model.

The paper provides novel data to predict the fouling effects on the performance of foam‐wrapped tube bundles as air‐cooled heat exchangers. It is observed that depending on the deposited layer thickness, the increased pressure drop and heat transfer deterioration can be very significant.

This paper fulfils an identified need to study fouling effects on thermohydraulic performance of a foam heat exchanger.

This paper attempts to cover the thermal processes in syntactic metal foams. Regularshaped cubic closed‐cell structures with spherical pores are investigated by means of the finite element method. Based on the numerical modelling of the microstructure, the effective macroscopic thermal properties are evaluated. Different relative densities (0.95 ‐ 0.5) and different base materials (aluminium and iron) are considered. Furthermore, the influence of the geometry, i.e. spherical ‐ cubical for 3D and circular ‐ rectangular for 2D models, is investigated. The focus is on such cellular materials where the transport of heat is dominated by solid conduction and thermal radiation; contributions from gaseous conduction and convection are neglected.

Aluminium stearate is a fine, bulky, odourless and colourless powder forming a plastic mass when heated, having the properties both of organic and inorganic matter. It embraces most of the characteristics of other metallic stearates and is regarded as the most important of these. Several studies of the material have already appeared in past years.

Nanofluids are widely used in heat transfer phenomena owing to the higher rate of heat removal as compared to their base fluids. Nanoparticle’s motion in nanofluids is analysed by slip mechanisms that consider physical properties, which can be found in literature. It is assumed that among few, only Brownian motion and thermophoresis affect the slip mechanism to produce a relative velocity between the nanoparticles and the base fluid. The purpose of this paper is to study the effects of Brownian motion and thermophoresis in a square cavity by considering it pure fluid as well as porous cavity.

A finite element method is used to solve the flow porous equations together with the heat transfer equation and the mass transfer equation numerically. The heat and mass transfer equations were modified to take into consideration the Brownian motion as well as the thermophoresis effect.

A negligible amount of Brownian motion and thermophoresis effect has been found by considering 1 to 3 Vol.% of aluminium oxide as nanoparticles suspended in base fluid of water.

This study has provided an interesting insight into the importance of Brownian motion as well as the thermophoresis effect in heat enhancement.

The present study is believed to be an interesting and original contribution on nanofluid thermal behaviours.

The purpose of this article is on the functional usability of metal additive manufacturing (AM) direct metal laser sintering (DMLS) production technology process parameters in the construction industry. In the study, the advantages of thermal optimization and weight reduction in the case of the use of foam metals obtained by changing the hatch distance the production process parameter, in the production of facade panels in the architectural field are revealed.

The methods in the study; production of the small scaled facade panels with nine different hatch distance parameters, determination of the thermal change with the infrared thermography method, microstructure examination, weight measurement.

The paper lays the groundwork for the manufacturability of lighter and lower thermal conductivity facade panels by changing the hatch distance parameters. Within the scope of the study, the definition of semi-open-cell foam aluminum and the product screening strategy offers innovation. Within the scope of the study, this scope is shared as an algorithmic summary. In addition, the study offers a new perspective within the scope of multiple optimizable panel production in facade panels with AM technology.

Hatch distance parameter change was first discussed in this study in the architectural field, and a semi-open cell foam aluminum panel was obtained with the scanning strategy determined within the scope of the study. This panel geometry, which is defined as semi-open cell foam aluminum, can be used as a design element by painting or coating the outer surface, it can be stated that it will also provide thermal and weight optimization.