A. Lkouen^1,*, M. Lamrani², A. Meskini¹, A. Khabbazi³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.8, pp. 2013-2026, 2023, DOI:10.32604/fdmp.2023.026929

Abstract Most of the energy savings in the building sector come from the choice of the materials used and their microphysical properties. In the present study, through numerical simulations a link is established between the thermal performance of composite materials and their microstructures. First, a two-phase 3D composite structure is modeled, then the RSA (Random Sequential Addition) algorithm and a finite element method (FE) are applied to evaluate the effective thermal conductivity of these composites in the steady-state. In particular, building composites based on gypsum and clay, consolidated with peanut shell additives and/or cork are considered.… More > Graphic Abstract

Soumaya Zormati, Fadhel Aloulou^*, Habib Sammouda

Journal of Renewable Materials, Vol.11, No.5, pp. 2345-2365, 2023, DOI:10.32604/jrm.2023.026170

Abstract

The objective of this study is to analyze the effects of using surfactant (CTAB) and cellulose nanofibers (NFC) as an admixture in cement mortars. We examined composite properties as porosity, compression energy, thermal conductivity and hydration. The results showed that with the addition of 0.7% by weight of NFC per emulsion in the presence of a cationic surfactant (CTAB). The new material produced presented a dry porosity between 4.7% and 4.4%, compressive strength between 9.8 and 22.9 MPa, and thermal conductivity between 0.95 and 2.25 W·m⁻¹·K⁻¹. Thus we show better mechanical and thermal performance than that

More > Graphic Abstract

Yiwen Zhang¹, Jianjun Xie^1,*, Minghui Sun¹, Shaolong Wang¹, Tengfei Xu^2,3, Yonggen Xu^2,3, Xiaoqing Ding^2,3, Ying Shi¹, Lei Zhang¹

Journal of Renewable Materials, Vol.11, No.5, pp. 2125-2141, 2023, DOI:10.32604/jrm.2023.025127

Abstract Foam glass is a kind of green building material that is widely used because of its excellent thermal insulation and mechanical properties. In this study, the borosilicate foam glass was fabricated by powder sintering method using recycled soda lime waste glass, quartz, and borax as the primary raw materials. CaCO₃ was used as a foaming agent and Na₂CO₃ as a flux agent. Results showed that as the quartz content decreases from 30 to 17.5 wt.% and borax content increases from 5 to 17.5 wt.%, the pore size, porosity, and thermal insulation of borosilicate foam glass increase significantly, while… More > Graphic Abstract

Hamadou-Ali Mohamed^1,*, Benazzouk Amar^1,*, Haïkel Ben Hamed¹, Arash Jamali²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.3, pp. 723-741, 2023, DOI:10.32604/fdmp.2022.021841

Abstract The feasibility of a sustainable non-autoclaved cellular concrete, based on flax vegetable co-products, for the production of usable specimen in the lightweight construction field, has been investigated experimentally. The produced specimen, containing various volume ratios of flax particles with respect to preformulatd Tradical PF70 lime binder of 0, 1, and 2, were lightened by creating a porous structure in the matrix through the addition of 0.3% wt. Aluminium powder (able to react with calcium hydroxide from the binder and result in microscopic air-bubbles). Fresh and hardened specimen properties, including hydration, fresh density, porosity, hardened density,… More >

Yue Yu^*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.3, pp. 697-709, 2023, DOI:10.32604/fdmp.2022.021482

Abstract The sol-gel method is used to prepare a new nano-alumina aerogel structure and the thermal properties of this nanomaterial are investigated comprehensively using electron microscope scanning, thermal analysis, X-ray and infrared spectrometer analysis methods. It is found that the composite aerogel alumina material has a multi-level porous nano-network structure. When employed for the thermal insulation of high-rise buildings, the alumina nanocomposite aerogel material can lead to effective energy savings in winter. However, it has almost no energy-saving effect on buildings where energy is consumed for cooling in summer. More >

Bin Lin¹, Zhengyu Li^2,*, Dong Wen², Jianchao Liu², Shan Yang³, Yong Zhou², Chao Lu⁴, Qian Qiu^4,5

CMC-Computers, Materials & Continua, Vol.74, No.1, pp. 1509-1521, 2023, DOI:10.32604/cmc.2023.032557

Abstract The further development of catalytic elements has been plagued by activation and binary problems. The automatic shift model that has emerged in recent years helps components achieve full range. However, the detection data still remains unstable in the shift area (7%~13%). This paper proposes a Catalytic Combustion and Thermal Conductivity (CCTC) model for the specified range, which can be explained from two aspects based on the existing methods. On the one hand, it uses iterative location search to process heterogeneous data, judges the prediction position of data points, and then gives weight evaluation. On the… More >

M. Y. Dhange^a,*, G. C. Sankad^a, Ishwar Maharudrappa^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-6, 2022, DOI:10.5098/hmt.18.36

Abstract The present paper investigates the impacts of heat transfer and magnetic field on the boundary layer flow of Casson fluid over a linearly stretching sheet. The researchers have introduced analytical and numerical solutions for the momentum and energy equations by transforming the equations into the system of ordinary differential equations with the aid of the similarity transformations technique. The velocity and temperature profiles for pertinent constraints like Casson fluid constraint, Chandrasekhar number, Prandtl number, and thermal conductivity are presented through graphs. The influence of the wall shear stress and the Prandtl number increases while the… More >

Lisheng Deng^1,2, Hongyu Huang^2,*, Zhaohong He², Shijie Li², Zhen Huang², Mitsuhiro Kubota³, You Zhou^4,*, Dezhen Chen¹

Journal of Renewable Materials, Vol.10, No.11, pp. 2895-2906, 2022, DOI:10.32604/jrm.2022.019071

Abstract Thermochemical heat storage material inorganic hydrate LiOH is selected as a promising candidate material for storing low-temperature heat energy because of its high energy density (1440 kJ/kg) and mild reaction process. However, the low hydration rate of LiOH limits the performance of low temperature thermochemical heat storage system as well as the thermal conductivity. In this study, porous-graphene/LiOH composite thermochemical heat storage materials with strong water sorption property and higher thermal conductivity were synthesized by hydrothermal process. The experimental results show that the hydration rate of the composites was greatly improved. The heat storage density More >

Jiayu Zhang, Zhenyang Li, Xinli Zhang^*

Journal of Renewable Materials, Vol.10, No.11, pp. 2871-2881, 2022, DOI:10.32604/jrm.2022.019373

Abstract Geopolymers are inorganic aluminosilicate materials, which have been a great research interest as a material for sustainable development. However, they possess relatively low toughness properties similar to brittle solids. The limitation may be altered by fiber reinforcement to improve their strength and toughness. This research describes the synthesis of bamboo shaving (BS) reinforced geopolymer composites and the characterization of their mechanical properties. The effect of BS content (0–2 wt. %) on the physical and mechanical properties and microstructure of metakaolin based geopolymer paste were investigated. The workability, setting time, bulk density, apparent porosity, thermal conductivity,… More >

John Paul¹, K. Kadirgama¹, M. Samykano^2,*, R. Saidur³, A. K. Pandey³, R. V. Mohan⁴

Energy Engineering, Vol.119, No.4, pp. 1299-1325, 2022, DOI:10.32604/ee.2022.019172

Abstract

Buildings contribute to 33% of total global energy consumption, which corresponds to 38% of greenhouse gas emissions. Enhancing building’s energy efficiency remains predominant in mitigating global warming. Advancements in thermal energy storage (TES) techniques using phase change material (PCM) have gained much attention among researchers, primarily to minimize energy consumption and to promote the use of renewable energy sources. PCM technology stays as the most promising technology for developing high-performance and energy-efficient buildings. The major drawback of PCM is its poor thermal conductivity which limits its potential use which could be resolved by dispersing conductive nanofillers.

… More > Graphic Abstract