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The purpose of this paper is to demonstrate a method for modeling of cellular structures by means of Voronoi tessellation and to conduct a validation by comparison with real metal foam structures.

Heat propagation behavior of open-pore metal foams is studied for both experimental as well as computer-modeled structures showing excellent agreement. The 3D open-pore structure of the real foam is reconstructed from 2D light microscope images in-depth.

An algorithm to create synthetic open-pore foam structures has been developed.

The algorithm for modeling synthetic open-pore cellular structures allows the random distribution of the individual pores close to reality.

The purpose of this paper is to introduce different methods for measuring the porosity of metal foams, and especially present a new method for conveniently measuring the open porosity that has a stronger impact on a number of physical properties of the porous product.

Metal foam is a kind of material that utilizes the function of pores inside the porous body. For such materials, the porosity is an important factor or even a key factor to determine a number of the practical parameters, such as the conductivity, acoustic properties and mechanical performances. Especially, the open porosity has a stronger impact on the sound absorption, electromagnetic shielding, heat transfer of the porous product, as well as the performances of using the internal pore surface. Therefore, it would be meaningful to find the simple and convenient to well measure the open porosity of metal foams.

In the present new method, the open porosity can be obtained directly by different volume parameters of the porous sample, while it can only by some weight indexes of the porous sample in other measuring methods.

The characteristic of this new method makes the measurement simpler and more convenient in this new method than in the other methods.

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.

This paper aims to discuss about the two-dimensional numerical simulations of fluid flow and heat transfer through high thermal conductivity metal foams filled in a vertical channel using the commercial software ANSYS FLUENT.

The Darcy Extended Forchheirmer model is considered for the metal foam region to evaluate the flow characteristics and the local thermal non-equilibrium heat transfer model is considered for the heat transfer analysis; thus the resulting problem becomes conjugate heat transfer.

Results obtained based on the present simulations are validated with the experimental results available in literature and the agreement was found to be good. Parametric studies reveal that the Nusselt number increases in the presence of porous medium with increasing thickness but the effect because of the change in thermal conductivity was found to be insignificant. The results of heat transfer for the metal foams filled in the vertical channel are compared with the clear channel in terms of Colburn j factor and performance factor.

This paper serves as the current relevance in electronic cooling so as to open up more parametric and optimization studies to develop new class of materials for the enhancement of heat transfer.

The novelty of the present study is to quantify the effect of metal foam thermal conductivity and thickness on the performance of heat transfer and hydrodynamics of the vertical channel for an inlet velocity range of 0.03-3 m/s.

Common Aero Vehicles (CAVs) are relatively small‐size, un‐powered, self‐maneuvering vehicles equipped with a variety of weapons and launched from space. One of the major obstacles hampering a full the realization of the CAV concept is a present lack of lightweight, high‐temperature insulation materials which can be used for construction of the CAV’s thermal protection system (TPS). A computational analysis is utilized in the present work to examine the suitability of a carbon‐based, coal‐derived foam for the TPS applications in the CAVs. Toward that end, a model is developed for the high‐temperature effective thermal conductivity of foam‐like materials. In addition, an insulation sizing procedure is devised to determine the minimum insulation thickness needed for thermal protection of the vehicle structure at different sections of a CAV. It is found that the carbon‐based foam material in question can be considered as a suitable TPS insulation material at the leeward side and at selected portions of the windward side of a CAV (specifically the portions which are further away from the vehicle nose).

The purpose of this paper is to provide a summarization and review of the present author's main investigations on failure modes of reticular metal foams under different loadings in engineering applications.

With the octahedral structure model proposed by the present authors themselves, the fundamentally mechanical relations have been systematically studied for reticular metal foams with open cells in their previous works. On this basis, such model theory is continually used to investigate the failure mode of this kind of porous materials under compression, bending, torsion and shearing, which are common loading forms in engineering applications.

The pore-strut of metal foams under different compressive loadings will fail in the tensile breaking mode when it is brittle. While it is ductile, it will tend to the shearing failure mode when the shearing strength is half or nearly half of the tensile strength for the corresponding dense material and to the tensile breaking mode when the shearing strength is higher than half of the tensile strength to a certain value. The failure modes of such porous materials under bending, torsional and shearing loads are also similarly related to their material species.

This paper presents a distinctive method to conveniently analyze and estimate the failure mode of metal foams under different loadings in engineering applications.

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.

The efficiency of fractional derivative and hereditary combined approach in modeling viscoelastic behavior of soft foams was successfully addressed in Elfarhani et al. (2016a). Since predictions obtained on flexible polyurethane foam (FPF) type A (density 28 kg m⁻³) were found very promoting, the purpose of this paper is to apply the approach basing on two other types of foams. Both soft polyurethane foams type B of density 42 kg m⁻³ and type C of density 50 kg m⁻³ were subjected to multi-cycles compressive tests.

The total foam response is assumed to be the sum of a non-linear elastic component and viscoelastic component. The elastic force is modeled by a seven-order polynomial function of displacement. The hereditary approach was applied during the loading half-cycles to simulate the short memory effects while the fractional derivative approach was applied during unloading cycles to simulate the long memory effects. An identification methodology based on the separation of the measurements of each component force was developed to avoid parameter admixture problems.

The proposed model reveals good reliability in predicting the responses of the two considered flexible foams. Predictions as measurements establish that residual responses were negligible compared to elastic and viscoelastic damping responses.

The development of a new combined model reveals good reliability in predicting the responses of the two polyurethane foams type A and B.

The purpose of this study is to analyze heat transfer for solid–liquid phase change in two inclined cavities assisted with open cell and closed cell porous structures for enhancement of heat transfer and compare them.

The heat transfer analysis is done numerically. The set of conservation equations for mass, momentum and energy for phase change material (PCM) and conduction heat transfer equation for metal frame are solved. Furthermore, temperature and solid–liquid fraction distributions for a cavity filled only with PCM are also obtained for comparison. The porosity is 0.9 for both porous structures. Rayleigh number and inclination angle change from 1 to 10⁸, and from −90° to 90°, respectively.

The present study reveals that the use of closed cell structures not only can make phase change faster than open cell structure (except for Ra = 10⁸ and = 90°) but also provide more stable process. The use of a closed cell porous structure in a cavity with PCM can reduce melting period up to 55% more than a cavity with an open cell porous structure. The rate of this additional enhancement depends on Rayleigh number and inclination angle.

To the best of the authors’ knowledge, this is the first time that the comparison between closed cell and open cell porous structures for heat transfer enhancement in a solid/liquid phase change process is reported. Authors believe that the present study will lead more attentions on the use of closed cell porous structures.

The purpose of this paper is to investigate the impact of ligament shape on radiative behavior, with a specific focus on the inter-dependence among porosity, ligament shape and radiative characteristics.

Using Surface Evolver to generate a base structure and then coherently modifying it, the model presented in this paper aims to tackle these challenges in an improved fashion, all the while making it possible to systematically assess the influence of ligament shape on radiation heat transfer in foams, focussing on the porosity-dependence of ligament shape.

It is found that the prediction of numerical models, at constant size and specific surface of the cells, is strongly affected by the dependence of ligament shape on the porosity.

The above said dependence has, therefore, to be accounted for in robust modeling of radiation in foams with a wider range of porosities.

The radiative behavior of metal foams has been studied in literature using analytical, numerical and experimental approaches. However, only few researches focussed their attention on the assessment of the relevance of specific micro-structural (i.e. sub-cell size) characteristics.