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The purpose of this paper is mainly to know: (1) the sound absorption coefficient of porous composite structures constituted by a new kind of lightweight ceramic foam and perforated plate; (2) the availability of an equivalent porous material model, recently proposed by the present author, to these composite structures in sound absorption.

A kind of lightweight ceramic foam with bulk density of 0.38–0.56 g·cm-3 was produced by means of molding, drying and sintering. The effect of stainless steel perforated plate on sound absorption performance of the ceramic foam was investigated by means of JTZB absorption tester.

The results indicate that the sound absorption performance could be obviously changed by adding the stainless steel perforated plate in front of the porous samples and the air gap in back of the porous samples. Adding the perforated plate to the porous sample with a relatively large pore size, the sound absorption performance could be evidently improved for the composite structure. When the air gap is added to the composite structure, the first absorption peak shifts to the lower frequency, and the sound absorption coefficient could increase in the low frequency range.

Based on the equivalent porous material model and the “perforated plate with air gap” model, the sound absorption performance of the composite structures can be simulated conveniently to a great extent by using Johnson-Champoux-Allard model.

The purpose of this paper is to provide an optimization schedule of structural parameters for the sound absorption performance of a cellular ceramic foam in the sound frequency range of 200–4,000 Hz.

The cellular ceramic foam with porosity of about 60–75% and the pore size of about 1–7 mm was successfully prepared by using natural zeolite powder as the main raw material. For this ceramic foam, the sound absorption performance was measured, and the absorption structure was optimized by some important structural parameters. With orthogonal experiment, optimization of structural parameters was found for absorption performance. By means of the range analysis method, the main factor is known to influence the performance of ceramic foam.

The present ceramic foam may have good absorption performance although at relatively low frequencies of 400–4,000 Hz while structural parameters of sample are appropriately combined. With orthogonal experiment, optimization of structural parameters for the absorption performance was found to be as follows: sample thickness, 25 mm; porosity, 73.5%; pore size, 4–5 mm and air gap depth, 20 mm. To influence the performance, sample thickness is the main factor, air gap depth is the second and both of pore size and porosity would have a relatively slight effect.

This paper presents a method to optimize the structural parameters of a cellular ceramic foam for sound absorption performance by means of orthogonal experiment.

The purpose of this paper is to provide an investigation on a new kind of adsorbent materials, namely, the Prussian blue analog (PBA)-loaded albite-base porous ceramic foam, which can effectively adsorb the heavy metal ion in the wastewater.

The natural zeolite powder has been used as the primary raw material to make a sort of porous ceramic foam by impregnating polymer foam in slurry and then sintering. Adjusting the technological parameters could control the bulk density of the ceramic product, which could float on water with the bulk density less than 1 g/cm³ and also sink in water with the bulk density higher than 1 g/cm³. After desilicating the porous ceramic foam, an Al-Fe type PBA with a strong function of ion exchange was loaded on the ceramic surface by directly yielding.

The adsorption performance for harmful metal ions was greatly improved by combining together the high adsorption capability of the PB analog and the efficient high specific surface area of the porous ceramic foam.

This work presents a PBA-loaded albite-base porous ceramic foam that can effectively adsorb the harmful substance in water, and the adsorption efficiency for some typical harmful ions, i.e., Cd²⁺, Cs⁺ and As(V), was examined under different conditions of the experimental period, the pH value and the ion concentration in the tested solution.

The purpose of this paper is to present experimental studies on the designed muffler which contains ceramic foam and has the integration function of purification and noise elimination.

Comparative tests were done on a diesel engine with no muffler, the original muffler and the purification muffler. The soot index (light absorption coefficient), A-weighted sound pressure level and fuel consumption rate, which were collected by the partial flow opacity method, the insertion loss measurement of spatial five points and the load characteristics tests, respectively, and the effects of purification and noise elimination were studied.

The results of this paper state that the purification muffler shows great improvement on exhaust soot purification and noise elimination. The variation in diesel fuel consumption rate was small, the sound pressure level of purification muffler was reduced by 6 to 10 dB, the insertion loss of the purification muffler was increased by 6.41 dB and the average light absorption coefficient decreased by 57.8 percent compared with the original muffler.

The value of this study is that it supplies a purification muffler which contains a ceramic foam. Under the prerequisite of little effect on the fuel economy of diesel engine, the purification muffler shows great improvement in exhaust soot purification and noise elimination.

Gives a bibliographical review of the finite element analyses of sandwich structures from the theoretical as well as practical points of view. Both isotropic and composite materials are considered. Topics include: material and mechanical properties of sandwich structures; vibration, dynamic response and impact problems; heat transfer and thermomechanical responses; contact problems; fracture mechanics, fatigue and damage; stability problems; special finite elements developed for the analysis of sandwich structures; analysis of sandwich beams, plates, panels and shells; specific applications in various fields of engineering; other topics. The analysis of cellular solids is also included. The bibliography at the end of this paper contains 655 references to papers, conference proceedings and theses/dissertations dealing with presented subjects that were published between 1980 and 2001.

The purpose of this paper is to provide an investigation on a new kind of photocatalytic material, namely, the porous ceramic foam loading titanium dioxide, which can make an effective photocatalytic degradation of the methyl orange (MO) solution in the wastewater.

The natural zeolite powder has been used as the primary raw material to produce a sort of lightweight porous ceramic foam by impregnating polymer foam in slurry and then sintering. With the sol-gel method, a kind of open-cell reticular porous ceramic foam loading TiO₂ film was obtained having a good photocatalytic action, and the resultant porous composite product presents the bulk density of 0.3~0.6 g/cm³ to be able to float on water.

The MO could tend to be completely degraded in the solution with a certain concentration by the TiO₂-loaded ceramic foam irradiated with ultraviolet light, and this composite foam was found to have high degradation efficiency for the MO solution in a wide range of pH.

This work presents a TiO₂-loaded ceramic foam that can effectively photo-catalyze to degrade the MO in water, and the degradation efficiency were examined under different conditions of the MO solution with various pH values.

To improve the high-temperature wear properties of the SiCp/A359 composite, foamed iron-reinforced SiCp/A359 composite (A359–SiCp/Fe) is prepared. The purpose of this study is to investigate the tribological behavior and mechanism of the A359–SiCp/Fe composites at different temperatures (100–500 °C) and loads (7 N, 10 N and 12 N).

The A359–SiCp/Fe composite was fabricated by vacuum-assisted infiltration. The dry sliding tribological behaviors of A359–SiCp/Fe composite were investigated using the ball-on-disc-type tribometer. The worn surface and wear morphology of the longitudinal section were examined using field emission scanning electron microscopy and metallographic microscope.

The critical transition temperature for severe wear in A359–SiCp/Fe composite was 50–100 °C higher than in SiCp/A359 composite. Foamed iron prevents exfoliation cracks from penetrating deeper into the matrix. The friction coefficient stability of the A359–SiCp/Fe composite was higher than the unreinforced composite at elevated temperatures. With the increase in temperature, the friction-affected layer was severely worn, and the wear mechanism transferred from abrasion and delamination to oxidation and plastic flow, respectively.

The preparation procedure for aluminum matrix composites reinforced with foamed metal has been less reported, and the research on the tribological behavior and mechanism of A359–SiCp/Fe composite at various temperatures is insufficient. The foamed iron structure considerably enhances the wear properties of SiCp/A359 composite in elevated temperature conditions.

This study aims to introduce a metal porous burner design. Literature is surveyed in a comprehensive manner to relate the current design with ongoing research. A demonstrative computational fluid dynamics (CFD) analysis is presented with projected flow conditions by means of a common commercial CFD code and turbulence model to show the flow-related features of the proposed burner. The porous metal burner has a novel design, and it is not commercially available.

Based on the field experience about porous burners, a metal, cylindrical, two-staged, homogenous porous burner was designed. Literature was surveyed to lay out research aspects for the porous burners and porous media. Three dimensional solid computer model of the burner was created. The flow domain was extracted from the solid model to use in CFD analysis. A commercial computational fluid dynamics code was utilized to analyze the flow domain. Projected flow conditions for the burner were applied to the CFD code. Results were evaluated in terms of homogenous flow distribution at the outer surface and flow mixing. Quantitative results are gathered and are presented in the present report by means of contour maps.

There aren’t any flow sourced anomalies in the flow domain which would cause an inefficient combustion for the application. An accumulation of gas is evident around the top flange of the burner leading to higher static pressure. Generally, very low pressure drop throughout the proposed burner geometry is found which is regarded as an advantage for burners. About 0.63 Pa static pressure increase is realized on the flange surface due to the accumulation of the gas. The passage between inner and outer volumes has a high impact on the total pressure and leads to about 0.5 Pa pressure drop. About 0.03 J/kg turbulent kinetic energy can be viewed as the highest amount. Together with the increase in total enthalpy, total amount of energy drawn from the flow is 0.05 J/kg. More than half of it spent through turbulence and remaining is dissipated as heat. Outflow from burner surface can be regarded homogenous though the top part has slightly higher outflow. This can be changed by gradually increasing pore sizes toward inlet direction.

Combustion via a porous medium is a complex phenomenon since it involves multiple phases, combustion chemistry, complex pore geometries and fast transient responses. Therefore, experimentation is used mostly. To do a precise computational analysis, strong computational power, parallelizing, elaborate solid modeling, very fine meshes and small time steps and multiple models are required.

Findings in the present work imply that a homogenous gas outflow can be attained through the burner surfaces while very small pressure drop occurs leading to less pumping power requirement which is regarded as an advantage. Flow mixing is realizable since turbulent kinetic energy is distinguished at the interface surface between inner and outer volumes. The porous metal matrix burner offers fluid mixing and therefore better combustion efficiency. The proposed dimensions are found appropriate for real-world application.

Conducted analysis is for a novel burner design. There are opportunities both for scientific and commercial fields.

A novel numerical formulation of the two‐phase macroscopic balance equations governing the flow field in incompressible porous media is presented. The numerical model makes use of the weighted average flux method and total variation diminishing flux limiting techniques, and results in a second‐order accurate scheme. A shock tube study was carried out to examine the interaction of a normal shock wave with a thin layer of porous, incompressible cellular ceramic foam. Particular attention was paid to the transmitted and reflected flow fields. The numerical model was used to simulate the experimental test cases, and their results compared with a view to validate the numerical model. A phenomenological model is proposed to explain the behaviour of the transmitted flow field.

The quality of lost foam casted engineering components is directly influenced by the characteristics of the respective ceramic shell mold (CSM) and hence casting pattern. In this present work, rapid prototyping (RP) was used to fabricate the lattice structured patterns (LSPs) to reduce the defects and cracks in CSM during the heating stage.

The quality of the LSPs was accessed by measuring the dimensional accuracy. Further, the thermal stress in the CSM during the heating of porosity varied LSPs was analyzed using ANSYS software package 16.0. The Ni-alloy casting was fabricated by using the designed LSP and compared with its respective CAD model to access its quality.

The obtained results revealed that the Wigner–Seitz LSPs retained high accuracy and minimized the stress for defect-free CSM. Also, the thermal stress generated in the CSM depends upon the porosity coefficient of the LSP. Hence the interplay with porosity coefficient of LSPs leads to the formation of defect free CSM and hence high quality casting.

RP was used to develop LSPs and investigated the dependency of unit cell parameters on the accuracy of the final casting.