Laima Vevere^*, Beatrise Sture, Vladimir Yakushin, Mikelis Kirpluks, Ugis Cabulis

Journal of Renewable Materials, Vol.12, No.3, pp. 585-602, 2024, DOI:10.32604/jrm.2024.047350

Abstract Cryogenic insulation material rigid polyurethane (PU) foams were developed using bio-based and recycled feedstock. Polyols obtained from tall oil fatty acids produced as a side stream of wood biomass pulping and recycled polyethylene terephthalate were used to develop rigid PU foam formulations. The 4th generation physical blowing agents with low global warming potential and low ozone depletion potential were used to develop rigid PU foam cryogenic insulation with excellent mechanical and thermal properties. Obtained rigid PU foams had a thermal conductivity coefficient as low as 0.0171 W/m·K and an apparent density of 37–40 kg/m³. The developed rigid PU foams had… More > Graphic Abstract

S. MATHIVANAN^*, R. MOHAN, RAMES C PANDA, P. BALACHANDER¹

Journal of Polymer Materials, Vol.39, No.3-4, pp. 195-204, 2022, DOI:10.32381/JPM.2022.39.3-4.2

Abstract Optimum-designed footwear with polyurethane (PU) material for comfort is an important requirement for obese. Investigations on compressive behavior of varied designed footwear using 120 D PU material have been carried out. The energy absorption primarily depends on heel height, slope angle and load applied or body mass index of obese. Statistical analysis has been used to formulate the prediction of absorbed energy wherein a heel height of 30 mm with 20-degree angle provides optimum value with the incorporation of 120 D PU material. A coefficientof-determination (R² ) value of 0.9406 confirms the suitability of the statistical regression model. Hence, the… More >

Yuxuan Ying¹, Wei Huang^1,*, Yu-E Ma¹, Fan Peng¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.4, pp. 1-3, 2023, DOI:10.32604/icces.2023.010572

Abstract Intensive dynamic loadings are the main threats to the structural damage of protective structures and inner equipment, which has attracted a lot of attention in the field of advance impulsive resistance. Nanofluidic liquid foam (NLF) has become a novel and efficient energy absorption system due to its reusable energy absorption, ultra-high load transfer, and high energy absorption ratio. In order to solve the current problem that the energy absorption mechanism of NLF is still unclear, this paper conducted a systematic experimental study on the dynamic compression and energy absorption behaviours of NLF. The quasi-static cyclic compression experiments with different liquid… More >

Haoyuan Guo¹, Jianxun Zhang^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.4, pp. 1-1, 2023, DOI:10.32604/icces.2023.09071

Abstract In this paper, the dynamic response of clamped rectangular sandwich tubes with metal foam core under transverse blast loading is studied by analytical analysis and FE simulation. It is assumed that the local denting occurs before the overall bending, and the local denting leads to the reduction of the fully plastic bending moment of cross-section. First, based on the modified solution for the maximum deflection of the solid beam under transverse blast loading, a semiempirical analytical solution for the dynamic response of rectangular hollow metal tube is given subjected to transverse blast loading considering local denting effect and combined axial… More >

Haiqi Feng¹, Wei Huang^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.3, pp. 1-2, 2023, DOI:10.32604/icces.2023.09347

Abstract Intensive dynamic loadings are the main threats to the structural damage of protective structures and inner equipment, which has attracted a lot of attention in the field of advance impulsive resistance. Nanofluidic liquid foam (NLF) has become a novel and efficient energy absorption system due to its reusable energy absorption, ultra-high load transfer, and high energy absorption ratio [1-7]. In order to solve the current problem that the energy absorption mechanism of NLF is still unclear, this paper conducted a systematic experimental study on the dynamic compression and energy absorption behaviours of NLF. The quasi-static cyclic compression experiments with different… More >

Shaopeng Liu¹, Guowei Wang^2,3,*, Pengfei Liu¹, Dong Ye¹, Jian Song¹, Xing Liu¹, Yang Cheng^2,3

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.12, pp. 3045-3058, 2023, DOI:10.32604/fdmp.2023.029810

Abstract Foam drainage is the flow of liquid through the interstitial spaces between bubbles driven by capillarity and gravity and resisted by viscous damping. The so-called foam drainage gas recovery technology is a technique traditionally used to mitigate the serious bottom-hole liquid loading in the middle and late stages of gas well production. In this context, determining the optimal concentration of the bubble drainage agent is generally crucial for the proper application of this method. In this study, a combination of indoor experiments and theoretical analysis have been used to determine the pressure drop related to the foam-carrying capacity in a… More >

Lei Yang¹, Guangyan Huang^1,2,*, Tao Wang^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.4, pp. 1-2, 2023, DOI:10.32604/icces.2023.09759

Abstract In order to evaluate the blast mitigation effect of polyurethane foam in cylindrical explosion containment vessels (CECVs), a three-dimensional numerical simulation model was established. The Structured Arbitrary Lagrange-Euler (S-ALE) algorithm was applied in current simulations to define the coupling contact between TNT and Lagrange algorithm. The numerical model was verified by comparing the dynamic deformation and permanent deformation of the experiments. Based on the numerical simulation model after verification, the influence of polyurethane foam filling inside CECVs on the mitigation effect was investigated. The results revealed that compared with the ALE algorithm, the numerical simulations based on the S-ALE algorithm… More >

Shuai Wang^1,*, Lihong Liang^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.4, pp. 1-2, 2023, DOI:10.32604/icces.2023.09163

Abstract Compared to pure carbon nanotube (CNT) foam (CF) and pure graphene foam (GrF), the CNT/graphene composite foam show enhanced mechanical properties, using coarse-grained molecular dynamics method, the tensile and compressive properties and corresponding deformation mechanism of several typical CNT/graphene composite foams were studied. The CNT coating could enhance the bending resistance of graphene, based on the CNT-coated graphene flakes, the CNT-coated graphene foam (CCGF) is constructed, which shows better compressive modulus due to the enhanced bending resistance of CNT-coated graphene flakes compared to graphene in pure GrF [1]. CNT can enhance the mechanical properties of graphene foams not only by… More >

Elham Azadeh¹, Ummi Hani Abdullah^2,3, Christine Gerardin^1,*, Antonio Pizzi^1,*, Philippe Gerardin¹, Cesar Segovia⁴

Journal of Renewable Materials, Vol.11, No.10, pp. 3625-3645, 2023, DOI:10.32604/jrm.2023.030373

Abstract Water repellant, flexible biofoams using tannin esterified with various fatty acid chains, namely lauric, palmitic and oleic acids, by reaction with lauryl chloride, palmitoyl chloride, and oleyl chloride were developed and their characteristics compared with the equivalently esterified rigid biofoams. Glycerol, while initially added to control the reaction temperature, was used as a plasticizer yielding flexible biofoams presenting the same water repellant character that the equivalent rigid foams. Acetaldehyde was used as the cross-linking agent instead of formaldehyde, as it showed a better performance with the esterified tannin. The compression results showed a significant decrease of the Modulus of Elasticity… More >

Fangzhou Wang^a,* , Gennifer A. Riley^b, Munonyedi Egbo^c, Melanie M. Derby^b, Gisuk Hwang^c, Xianglin Li^a,†

Frontiers in Heat and Mass Transfer, Vol.15, pp. 1-8, 2020, DOI:10.5098/hmt.15.1

Abstract This study conducts pore-scale simulations and experiments to estimate the permeability of two different types of porous materials: metal foams and sintered copper particles with porosities of approximately 0.9 and 0.4, respectively. The integration of micro X-ray computed tomography with pore-scale computational fluid dynamics simulations develops a unique tool to capture the pore-scale geometry of porous media and accurately predict non-isotropic permeability of porous media. The pore-scale simulation not only results in improved prediction accuracy but also has the capability to capture non-isotropic properties of heterogeneous materials, which is a huge challenge for empirical correlations, volume averaged simulations, and simulations… More >