Inga Zotova^1,*, Edgars Kirilovs¹, Laura Ziemele²

Journal of Renewable Materials, Vol.12, No.3, pp. 603-613, 2024, DOI:10.32604/jrm.2024.047607 - 11 April 2024

Abstract Nowadays buildings contain innovative materials, materials from local resources, production surpluses and rapidly renewable natural resources. Phase Change Materials (PCM) are one such group of novel materials which reduce building energy consumption. With the wider availability of microencapsulated PCM, there is an opportunity to develop a new type of insulating materials, combinate PCM with traditional insulation materials for latent heat energy storage. These materials are typically flammable and are located on the interior wall finishing yet there has been no detailed assessment of their fire performance. In this research work prototypes of low-density insulating boards… More > Graphic Abstract

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 - 11 April 2024

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… More > Graphic Abstract

Noureddine Abouricha^1,*, Ayoub Gounni², Mustapha El Alami²

Frontiers in Heat and Mass Transfer, Vol.22, No.1, pp. 359-375, 2024, DOI:10.32604/fhmt.2024.047632 - 21 March 2024

Abstract In this paper, experimental and numerical studies of heat transfer in a test local of side heated from below are presented and compared. All the walls, the rest of the floor and the ceiling are made from plywood and polystyrene in sandwich form ( plywood- polystyrene- plywood) just on one of the vertical walls contained a glazed door (). This local is heated during two heating cycles by a square plate of iron the width , which represents the heat source, its temperature is controlled. The plate is heated for two cycles by an adjustable… More >

Ming Liu¹, Pinghua Zhu^2,*, Xiancui Yan², Haichao Li², Xintong Chen²

Journal of Renewable Materials, Vol.12, No.2, pp. 329-347, 2024, DOI:10.32604/jrm.2023.045381 - 11 March 2024

Abstract As socioeconomic development continues, the issue of building energy consumption has attracted significant attention, and improving the thermal insulation performance of buildings has become a crucial strategic measure. Simultaneously, the application of solid waste in insulation materials has also become a hot topic. This paper reviews the sources and classifications of solid waste, focusing on research progress in its application as insulation materials in the domains of daily life, agriculture, and industry. The research shows that incorporating household solid waste materials, such as waste glass, paper, and clothing scraps into cementitious thermal insulation can significantly… More >

Weijun Wang^1,*, Min Chen¹, Hui Yin¹, Yuan Li²

Energy Engineering, Vol.120, No.10, pp. 2433-2448, 2023, DOI:10.32604/ee.2023.028620 - 28 September 2023

Abstract To identify the parameters of the extended Debye model of XLPE cables, and therefore evaluate the insulation performance of the samples, the sparsity-promoting dynamic mode decomposition (SPDMD) method was introduced, as well the basics and processes of its application were explained. The amplitude vector based on polarization current was first calculated. Based on the non-zero elements of the vector, the number of branches and parameters including the coefficients and time constants of each branch of the extended Debye model were derived. Further research on parameter identification of XLPE cables at different aging stages based on… More >

Xu Yang^1,2, Jing Zhang^1,2, Chuanxian Luo^1,2, Qinqing Huang^1,2, Hui Xu^1,2, Guozhi Zhang^1,2,*

Energy Engineering, Vol.120, No.9, pp. 2115-2132, 2023, DOI:10.32604/ee.2023.027198 - 03 August 2023

Abstract In response to the problem of frequent leakage and false alarm of partial discharge insulation defects in GIS, this paper conducts experimental research on intermittent discharge characteristics of common solid insulation defects in GIS. Using true GIS to build a multi-source testing platform for intermittent discharge of solid insulation defects, and using pulse current method, ultra-high frequency method, ultrasonic method, and gas characteristic component detection method to study the variation law of intermittent discharge characteristics of solid insulation defects. The results show that: the intermittent discharge state of metal fouling defects on the solid insulation… More >

Li Xiao^1,2, Xu Yang^1,2,*, Guozhi Zhang^1,2, Lin Cheng^1,2, Yi Jiang^1,2, Chuanxian Luo^1,2, Jing Zhang^1,2

Energy Engineering, Vol.120, No.5, pp. 1239-1252, 2023, DOI:10.32604/ee.2023.025530 - 20 February 2023

Abstract In view of the effective perception demand of PD (Partial Discharge) insulation defect of in-service GIS (Gas Insulated Switchgear), the external UHF (Ultra High Frequency, 0.3−3 GHz) sensing technology for GIS PD insulation defect from resin hole is studied in this paper. Firstly, rectangular waveguide theory is used to analyze the electromagnetic wave propagation characteristics from rectangular resin hole in GIS disc insulator. It is found that the energy of leaked electromagnetic wave mainly concentrates in the frequency band above 1 GHz. Then based on this frequency band characteristics, a cavity-backed bowtie sensor for GIS… More >

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 - 13 February 2023

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

Yue Yu^*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.3, pp. 697-709, 2023, DOI:10.32604/fdmp.2022.021482 - 29 September 2022

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 >

Jianan Wu¹, Ke Xue², Zhaowei Ding³, Lei Lang³, Kang Gu³, Xiaolin Li⁴, Mingli Zhang⁵, Desheng Li^3,6,*

Journal of Renewable Materials, Vol.10, No.12, pp. 3167-3183, 2022, DOI:10.32604/jrm.2022.020265 - 14 July 2022

Abstract Thermal insulation is an important indicator to evaluate the construction material in cold region engineering. As we know, adding the industrial waste as lightweight aggregate or creating the pore inside the cement-based composite could make the texture loose, and the thermal insulating capacity of the material would be improved with this texture. Using these methods, the industrial by-product and engineering waste could be cycled in an efficient way. Moreover, after service the fragmented cement composites paste could be used as aggregate in the thermal insulating concrete again. While the porous texture is not favorable for… More > Graphic Abstract