scholarly journals ASSESSMENT OF THERMAL INSULATION INDICATORS OF BUILDING ENCLOSURES BY LINGUISTIC VARIABLES

2021 ◽  
Vol 29 (2) ◽  
pp. 77-86
Author(s):  
G. Ratushnyak ◽  
◽  
V. Pankevych ◽  

The classification of the factors influencing decision-making at an estimation of thermal conductivity of a heat-insulating cover of the building is offered. The relationship between the parameters of the thermal state of the thermal insulation of buildings and its energy efficiency is presented in the form of a logical conclusion tree. The logical inference tree at the system level characterizes the ratio of parameters that affect thermal conductivity. To create a mathematical model for expert assessment of the technical condition of the thermal insulation of the building, it is advisable to use the apparatus of fuzzy logic and fuzzy set theory. The formalization of quantitative and qualitative factors influencing the thermal efficiency of the building insulation shell has been carried out. When assessing the technical condition of the thermal insulation of the building (energy efficiency), quantitative and qualitative factors of influence are expressed through linguistic variables. Estimation of levels of linguistic variables is represented by term sets. Thermal conductivity as a factor in the thermal insulation of a building is related to the normative classification of energy efficiency of buildings in force in Ukraine.

2021 ◽  
Vol 1046 ◽  
pp. 71-76
Author(s):  
Yokasta García Frómeta ◽  
Francisco Ramírez Rivera ◽  
Víctor González Holguín ◽  
Jesús Cuadrado

In developing countries, large quantities of agricultural residues associated with harvests are generated, given that agriculture is one of the most important economic activities. The valorization of these residues for the construction sector could contribute to the improvement of energy efficiency in buildings. Through passive techniques, the construction of insulating thermal-acoustics panels, blocks, and aggregate for reinforced concrete can improve the energy efficiency. In this study, an experiment was performed to measure thermal conductivity of the Agricultural-Thermal Insulation Panel (ATIP) based on rice hulks. These Agricultural-Thermal Insulation Panels were elaborated follow a standard process to compaction of the rice hulks to be employed as insulation material with a panel dimension of 200x200x34.5(mm3). A “Hot Box” configuration was used to obtain the thermal conductivity of the panels, using different temperature gradients between hot and cold chambers.


Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3895 ◽  
Author(s):  
Bożena Orlik-Kożdoń

This article addresses the important problem of improving the energy efficiency of historic buildings, where due to the architectural value of the facade, thermal insulation should be placed from the inside. As a part of this publication, the author, on the basis of their own experience and research, presents and discusses selected problems to which special attention should be paid when designing this type of insulation. These are among other things: disturbances in the distribution of the temperature field on the partition; defects related to partial thermal insulation of partitions; the lack of detailed analysis of wall systems in terms of construction and their technical condition; wood decay; the selection of inadequate calculation methods, e.g., the simple method of Fokin–Glaser and many others. The author, on the basis of measurements and computational analysis, presents the methodology of a correct solution of such problems. This significantly simplifies currently applied methods.


2019 ◽  
Vol 109 (06) ◽  
pp. 510-514
Author(s):  
M. Reisinger ◽  
C. Dierolf ◽  
C. Schneider ◽  
A. Sauer ◽  
G. Hörcher

Der Beitrag präsentiert zunächst ein Klassifikationsschema für Druckluftsystem-Komponenten. Darauffolgend wird die Normenreihe ISO 20140 als Basis für ein standardisiertes Datenmanagement vorgestellt. Die Normenreihe beschreibt eine Methode für die Erfassung, Aggregation und Bewertung der Energieeffizienz und weiterer umweltrelevanter Faktoren von Fertigungssystemen. Dargestellt wird die Konzeption eines Datenmodellierung-Anwendungsfalls eines pneumatischen Systems in Form eines Demonstrators.   This paper introduces a schemata for the classification of compressed air system components. It presents the standard ISO 20140 as a standardized data modeling technique. The standard represents a method for evaluating energy efficiency and other factors influencing the environment of manufacturing systems. The presented use case is a pneumatic sub system of a smart compressed air system demonstrator.


2021 ◽  
Vol 13 (13) ◽  
pp. 7484
Author(s):  
Gabriel Fernando García Sánchez ◽  
Rolando Enrique Guzmán López ◽  
Roberto Alonso Gonzalez-Lezcano

Buildings consume a large amount of energy during all stages of their life cycle. One of the most efficient ways to reduce their consumption is to use thermal insulation materials; however, these generally have negative effects on the environment and human health. Bio-insulations are presented as a good alternative solution to this problem, thus motivating the study of the properties of natural or recycled materials that could reduce energy consumption in buildings. Fique is a very important crop in Colombia. In order to contribute to our knowledge of the properties of its fibers as a thermal insulator, the measurement of its thermal conductivity is reported herein, employing equipment designed according to the ASTM C 177 standard and a kinetic study of its thermal decomposition from thermogravimetric data through the Coats–Redfern model-fitting method.


Author(s):  
Jonathan Skelton

Thermoelectric generators (TEGs) convert waste heat to electricity and are a leading contender for improving energy efficiency at a range of scales. Ideal TE materials show a large Seebeck effect,...


Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1838
Author(s):  
Shi-Yi Qiu ◽  
Chen-Wu Wu ◽  
Chen-Guang Huang ◽  
Yue Ma ◽  
Hong-Bo Guo

Microstructure dependence of effective thermal conductivity of the coating was investigated to optimize the thermal insulation of columnar structure electron beam physical vapor deposition (EB-PVD coating), considering constraints by mechanical stress. First, a three-dimensional finite element model of multiple columnar structure was established to involve thermal contact resistance across the interfaces between the adjacent columnar structures. Then, the mathematical formula of each structural parameter was derived to demonstrate the numerical outcome and predict the effective thermal conductivity. After that, the heat conduction characteristics of the columnar structured coating was analyzed to reveal the dependence of the effective thermal conductivity of the thermal barrier coatings (TBCs) on its microstructure characteristics, including the column diameter, the thickness of coating, the ratio of the height of fine column to coarse column and the inclination angle of columns. Finally, the influence of each microstructural parameter on the mechanical stress of the TBCs was studied by a mathematic model, and the optimization of the inclination angle was proposed, considering the thermal insulation and mechanical stress of the coating.


2010 ◽  
Vol 21 (2) ◽  
pp. 187-194
Author(s):  
Colleen Trevino

Strategies for the management of small bowel obstructions have changed significantly over the years. Nonoperative medical management has become the mainstay of treatment of many small bowel obstructions. However, the key to the management of small bowel obstructions is identifying those patients who need surgical intervention. Identification of those at risk for bowel ischemia and bowel death is an art as much as it is a science. Using the current literature and the past knowledge regarding small bowel obstructions, the clinician must carefully identify the signs and symptoms that suggest the need for operative intervention. Classification of the obstruction, history and physical examination, imaging, response to decompression and resuscitation, and resolution or progression of symptoms are the key factors influencing the management of small bowel obstructions.


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