Study on Thermal-Quench Behaviors of GdBCO Coils Wound With Silicon Grease as an Insulation Material

The relevance of research in the factory laboratory of JSC «198 KZHI», which is part of the HC GVSU «Center», is dictated by the need to dispose of foam polystyrene waste that occurs in large quantities when producing the precast concrete. In the production of three-layer external wall panels, polystyrene heatinsulating plates of the PPS 17-R-A brand are used as an effective insulation material. The secondary use of PPS 17-R-A for its intended purpose, as a heater, is not possible. The volume of foam polystyrene produced varies from 25 to 45 m3 per month. Utilization (disposal) of foam polystyrene waste is an expensive undertaking. Its use as a filler in the production of expanded polystyrene blocks was tested in the factory’s laboratory to produce foam polystyrene concrete with specified physical and mechanical characteristics. The results of testing of expanded polystyrene concrete of classes B2.5 and B 7.5 are presented. It is shown that under the conditions of the reinforced concrete factory technology, the production of polystyrene concrete blocks is possible with the achievement of the design strength. The information presented in the article is aimed at motivating specialists who produce recast concrete to the possibility of using foam polystyrene waste for low-rise construction. Keywords: foam polystyrene, ecology, energy efficiency, foam polystyrene concrete, foam polystyrene heat insulation plates, precast concrete.

Download Full-text

Thermal insulation products for building applications. Determination of the tensile bond strength of the adhesive and of the base coat to the thermal insulation material

10.3403/02679458 ◽

2002 ◽

Keyword(s):

Bond Strength ◽

Thermal Insulation ◽

Tensile Bond Strength ◽

Insulation Material ◽

Thermal Insulation Material

Download Full-text

Energy and daylight performance of a smart window: Window integrated with thermotropic parallel slat-transparent insulation material

Applied Energy ◽

10.1016/j.apenergy.2021.116826 ◽

2021 ◽

Vol 293 ◽

pp. 116826

Author(s):

Yanyi Sun ◽

Xin Liu ◽

Yang Ming ◽

Xiao Liu ◽

Daniel Mahon ◽

...

Keyword(s):

Insulation Material ◽

Smart Window ◽

Daylight Performance

Download Full-text

Numerical study of the influence of thermal radiation on measuring semi-transparent thermal insulation material with hot wire method

International Communications in Heat and Mass Transfer ◽

10.1016/j.icheatmasstransfer.2021.105120 ◽

2021 ◽

Vol 121 ◽

pp. 105120

Author(s):

H. Zhang ◽

Y.X. Ma ◽

X. Wang ◽

G.H. Tang

Keyword(s):

Thermal Radiation ◽

Thermal Insulation ◽

Numerical Study ◽

Insulation Material ◽

Hot Wire ◽

Thermal Insulation Material ◽

Wire Method

Download Full-text

Melinacidin-Producing Acrostalagmus luteoalbus, a Major Constituent of Mixed Mycobiota Contaminating Insulation Material in an Outdoor Wall

Pathogens ◽

10.3390/pathogens10070843 ◽

2021 ◽

Vol 10 (7) ◽

pp. 843

Author(s):

(Aino) Maria A. Andersson ◽

Johanna Salo ◽

Raimo Mikkola ◽

Tamás Marik ◽

László Kredics ◽

...

Keyword(s):

Air Quality ◽

Indoor Air Quality ◽

Indoor Air ◽

Mass Spectrometry Analysis ◽

Major Constituent ◽

Bioactive Metabolites ◽

Its Sequencing ◽

Insulation Material ◽

Settled Dust ◽

Aspergillus Section

Occupants may complain about indoor air quality in closed spaces where the officially approved standard methods for indoor air quality risk assessment fail to reveal the cause of the problem. This study describes a rare genus not previously detected in Finnish buildings, Acrostalagmus, and its species A. luteoalbus as the major constituents of the mixed microbiota in the wet cork liner from an outdoor wall. Representatives of the genus were also present in the settled dust in offices where occupants suffered from symptoms related to the indoor air. One strain, POB8, was identified as A. luteoalbus by ITS sequencing. The strain produced the immunosuppressive and cytotoxic melinacidins II, III, and IV, as evidenced by mass spectrometry analysis. In addition, the classical toxigenic species indicating water damage, mycoparasitic Trichoderma, Aspergillus section Versicolores, Aspergillus section Circumdati, Aspergillus section Nigri, and Chaetomium spp., were detected in the wet outdoor wall and settled dust from the problematic rooms. The offices exhibited no visible signs of microbial growth, and the airborne load of microbial conidia was too low to explain the reported symptoms. In conclusion, we suggest the possible migration of microbial bioactive metabolites from the wet outdoor wall into indoor spaces as a plausible explanation for the reported complaints.

Download Full-text

Application of the Gaussian Mixture Model to Classify Stages of Electrical Tree Growth in Epoxy Resin

Sensors ◽

10.3390/s21072562 ◽

2021 ◽

Vol 21 (7) ◽

pp. 2562

Author(s):

Abdullahi Abubakar Mas’ud ◽

Arunachalam Sundaram ◽

Jorge Alfredo Ardila-Rey ◽

Roger Schurch ◽

Firdaus Muhammad-Sukki ◽

...

Keyword(s):

Epoxy Resin ◽

Gaussian Mixture Model ◽

Mixture Model ◽

Tree Growth ◽

Asset Management ◽

Gaussian Mixture ◽

Growth Stages ◽

Insulation Material ◽

Electrical Tree ◽

Electrical Trees

In high-voltage (HV) insulation, electrical trees are an important degradation phenomenon strongly linked to partial discharge (PD) activity. Their initiation and development have attracted the attention of the research community and better understanding and characterization of the phenomenon are needed. They are very damaging and develop through the insulation material forming a discharge conduction path. Therefore, it is important to adequately measure and characterize tree growth before it can lead to complete failure of the system. In this paper, the Gaussian mixture model (GMM) has been applied to cluster and classify the different growth stages of electrical trees in epoxy resin insulation. First, tree growth experiments were conducted, and PD data captured from the initial to breakdown stage of the tree growth in epoxy resin insulation. Second, the GMM was applied to categorize the different electrical tree stages into clusters. The results show that PD dynamics vary with different stress voltages and tree growth stages. The electrical tree patterns with shorter breakdown times had identical clusters throughout the degradation stages. The breakdown time can be a key factor in determining the degradation levels of PD patterns emanating from trees in epoxy resin. This is important in order to determine the severity of electrical treeing degradation, and, therefore, to perform efficient asset management. The novelty of the work presented in this paper is that for the first time the GMM has been applied for electrical tree growth classification and the optimal values for the hyperparameters, i.e., the number of clusters and the appropriate covariance structure, have been determined for the different electrical tree clusters.

Download Full-text

Influence of Far Infrared TiO2 and Multi-Walled Carbon Nanotubes Coatings on the Performance of a Hot Water Heater

Applied Sciences ◽

10.3390/app11157043 ◽

2021 ◽

Vol 11 (15) ◽

pp. 7043

Author(s):

Tun-Ping Teng ◽

Shang-Pang Yu ◽

Yeou-Feng Lue ◽

Qi-Lin Xie ◽

Hsiang-Kai Hsieh ◽

...

Keyword(s):

Carbon Nanotubes ◽

Heating Rate ◽

Heat Insulation ◽

Far Infrared ◽

Hot Water ◽

Insulation Material ◽

Water Heater ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Insulation Performance

This study selects titanium dioxide (TiO2) and multi-walled carbon nanotubes (MWCNTs) as far-infrared materials (FIRMs), and further adds water-based acrylic coatings to prepare far-infrared coatings (FIRCs). FIRCs are uniformly coated on #304 stainless steel sheets to make the test samples, which are then installed between the shell and insulation material of the hot water heater to measure the influences of various FIRCs on the performance of the hot water heater. The research results show no significant difference in the heating rate or heat insulation performance of the hot water heater with or without FIRCs coating. However, the uniformity of the water temperatures of the test samples is significantly improved with FIRCs. Considering that the uniformity of water temperature will inhibit the heating rate and heat insulation performance of the hot water heater, TiO2-FIRC should provide better performance improvement when applied to the hot water heater in this study. The application of TiO2-FIRC to large-scale hot water heaters with a high aspect ratio will effectively improve the quality of hot water supply in the future.

Download Full-text