scholarly journals The efficiency of a dynamically insulated wall in the presence of air leakages

2004 ◽  
Vol 8 (1) ◽  
pp. 83-94
Author(s):  
Angela Kalagasidis-Sasic
Keyword(s):  
System Analysis ◽  
Ventilation System ◽  
Building Envelope ◽  
Leading Role ◽  
Outdoor Climate ◽  
Dynamic Insulation ◽  
Building Components ◽  
Heat And Moisture ◽  
Alternative Designs ◽  
Indoor And Outdoor

The movement of air in and through the building envelope often plays a leading role in the transport of heat and moisture into the building. It is caused by pressure and temperature variations around the building envelope inbuilt ventilation system, occupancy, etc. In order to improve the energy consumption, alternative designs for the ventilation systems are considered. One of them is a dynamically insulated wall as an inlet unit for the supplying air. In order to predict the performance of a dynamically insulated wall, it is necessary to make an analysis of the building as a system. This paper presents such system analysis which takes into account the interaction between the building components and indoor and outdoor climate, both in terms of the air leakage and heat and mass transfer to and from the building components. It is shown that, in the presence of air leakages (unintentional openings) in the enclosure of the building, the efficiency of the dynamic insulation is significantly decreased.

Hygrothermal Initial Conditions - Case Studies

2016 ◽  
Vol 820 ◽  
pp. 273-278
Author(s):  
Marek Zozulák ◽  
Marián Vertaľ ◽  
Dušan Katunský
Keyword(s):  
Moisture Transfer ◽  
Initial Conditions ◽  
Building Envelope ◽  
The Body ◽  
Initial Condition ◽  
Moisture Condition ◽  
Building Simulations ◽  
Building Components ◽  
Outdoor Test ◽  
Heat And Moisture

In building simulations initial conditions express the actual hygrothermal state of building envelope. For the temperature field simulations initial condition is represented by the initial temperature in the body profile at the start of heat transfer. In-structure temperature varies quickly so temperature initial conditions are often neglected. The contribution shows various temperature initial conditions determination for insulated construction of outdoor test cell. We confirmed importance of setting the initial moisture condition for numerical analysis of complex heat and moisture transfer in multi-layer building components. Comparison of measured and calculated temperature profiles in structure show correctness initial condition consideration.

scholarly journals Damage risk analysis of a Timurid heritage located in Iran exposed to outdoor climate change (Ghiassieh school)

2021 ◽  
Vol 2069 (1) ◽  
pp. 012062
Author(s):  
Hamed Hedayatnia ◽  
Marijke Steeman ◽  
Nathan Van Den Bossche
Keyword(s):  
Climate Change ◽  
Building Envelope ◽  
Weather Data ◽  
Climate Change Effects ◽  
Outdoor Climate ◽  
Heritage Buildings ◽  
Research Goal ◽  
Building Components ◽  
Historical Heritage

Abstract The first step to preserving the historical heritage against global warming effects is finding how this phenomenon affects building material degradation. Due to the vulnerability of Iranian heritage to climate change and lack of proper literature, research on climate change’s impact on Timurid heritage buildings in Iran has been determined as the primary research goal. The study is performed by analysing weather data, HAM simulations, and different damage criteria. This paper aims to find an appropriate method to study climate change’s impact on historical buildings. A Timurid historical school is chosen as a case study to better understand the current climate change effects on building components. The analysis shows that the significantly rising air temperature and wind speed, along with reduced rainfall and humidity, causes a notable decrease in building envelope moisture content in addition to an increase in hydrated salt crystallisation cycles during the studied period. These fluctuations may have played a crucial role in the pathologies that can be observed on site, and their continuation and expansion in the future, as the models have predicted, may lead to irreparable damages to the building.

State policy of maintaining the innovative forms of employment in the context of the economy digitalization

2020 ◽  
pp. 81-90
Author(s):  
Olha Mulska ◽  
Olha Levytska ◽  
Valentyna Kutsyk
Keyword(s):  
Information And Communication Technologies ◽  
System Analysis ◽  
Employment Policy ◽  
Socially Responsible ◽  
State Budget ◽  
Economic Relations ◽  
Functional Flexibility ◽  
Leading Role ◽  
Methods Of Synthesis ◽  
Information And Communication

The purpose of the study is to analyze current trends in the evolution of forms of employment under the influence of the economy digitalization, as well as to substantiate the directions and means of public policy to regulate the conditions of effective employment in the new realities. Methods of synthesis and system analysis, groupings, logical analysis, strategic management, and system analysis were used in the research. The most significant characteristics of the sphere of employment in the conditions of the economy digitalization, in particular quantitative flexibility, functional flexibility, and space-time flexibility, are defined. The spheres of economy in which new professions are most in demand in Ukraine in the conditions of development of digitalization processes of the national economy are identified, in particular information and communication technologies, biotechnologies, medicine, energy, and its accumulation, power networks and energy consumption management, transport, especially water and air transport, education, and ecology. The directions, spheres, branches, and concrete sub-branches where new professions are in demand in the conditions of the economy digitalization are defined. The paper emphasizes the leading role of the information and communication technology sector, the development of which largely determines the emergence of new professions. The paper provides the conclusion that in this situation the new forms of employment cover great innovative potential, as well as shadow aspects (informal agreements), which exacerbate the problem of insufficient filling of social funds and reduction of tax revenues to the state budget. The priorities of effective employment policy in Ukraine in the global digitalization of economic relations are outlined based on the principles of flexicurity, best practices, and implementation of innovative solutions in building mutually beneficial and socially responsible relations between employer and employee.

Soil and ecological division into districts of the Baikal region

2018 ◽  
Vol 940 (10) ◽  
pp. 54-64 ◽  
Author(s):  
I.A. Belozertseva ◽  
A.A. Sorokovoj
Keyword(s):  
Baikal Region ◽  
Soil Cover ◽  
Soil Formation ◽  
Forest Steppe ◽  
Leading Role ◽  
Soil Cover Structure ◽  
Reflecting Surface ◽  
Heat And Moisture ◽  
Made In

On the basis of long-term researches of soils in the territory of Russia and Mongolia soil and ecological division into districts of the Baikal region is carried out. At division into districts the whole set of an environment of soil formation was considered. On the map of soil and ecological division into districts 13 mountain, mid-mountain, low-mountain taiga, foothill, hollow-valley, forest-steppe and steppe provinces reflecting surface device originality as the ratio of balance of heat and moisture forming a basis to zoning is shown against the background of difficult orography are allocated. In total 42 districts on lithologic-geomorphological features are allocated. In formation of distinctions of a soil cover of these provinces the leading role is played by bioclimatic factors and inside them the lithologic-geomorphological ones. In the view of structural approach of the district they are considered as territories with a certain natural change of several types of the soil cover structure caused by features of a relief and the parent rock. The map is made in the MapInfo program. It is revealed that on ill-defined width zoning of soils the vertical one which has a greater influence on soils of this region is imposed. Soils of the Baikal region are not similar to the soils located at the same latitude of the flat European territory of Russia. Zone soils of this territory are specific and original.

scholarly journals Application Method of a Simplified Heat and Moisture Transfer Model of Building Construction in Residential Buildings

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4180
Author(s):  
Joowook Kim ◽  
Michael Brandemuehl
Keyword(s):  
Latent Heat ◽  
Moisture Transfer ◽  
Residential Buildings ◽  
Building Energy ◽  
The United States ◽  
Building Envelope ◽  
Outdoor Environment ◽  
Transfer Model ◽  
Heat And Moisture Transfer ◽  
Heat And Moisture

Several building energy simulation programs have been developed to evaluate the indoor conditions and energy performance of buildings. As a fundamental component of heating, ventilating, and air conditioning loads, each building energy modeling tool calculates the heat and moisture exchange among the outdoor environment, building envelope, and indoor environments. This paper presents a simplified heat and moisture transfer model of the building envelope, and case studies for building performance obtained by different heat and moisture transfer models are conducted to investigate the contribution of the proposed steady-state moisture flux (SSMF) method. For the analysis, three representative humid locations in the United States are considered: Miami, Atlanta, and Chicago. The results show that the SSMF model effectively complements the latent heat transfer calculation in conduction transfer function (CTF) and effective moisture penetration depth (EMPD) models during the cooling season. In addition, it is found that the ceiling part of a building largely constitutes the latent heat generated by the SSMF model.

scholarly journals Study on IBS Cooling Panel Wall System with Difference Types of Cooling Mediums

2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Eny Nor Syahira Mohamad Hashim ◽  
◽  
Norhafizah Salleh ◽  
Noor Azlina Abdul Hamid ◽  
◽  
...  
Keyword(s):  
Relative Humidity ◽  
Air Conditioning ◽  
Ventilation System ◽  
Target Strength ◽  
Outdoor Temperature ◽  
Design Concepts ◽  
Building Ventilation ◽  
American Society ◽  
Wall System ◽  
Indoor And Outdoor

This paper proposes a cooling house system that can promote thermal comfort in buildings without air-conditioning. The cooling panel wall forms a part of an Integrated Building System (IBS), and is essentially made of tubes filled with either water or glycerin as the coolant. Target strength for the panel wall was designed based on the Malaysian Standard (MS) while the building ventilation system followed the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) standard. The results are reported based on indoor and outdoor temperature difference together with relative humidity to identify the best performing house model and also coolant. The outcome of this research is expected to add value to design concepts with a better promotion of air flow and circulation in the building, without over-usage of natural resources and higher building cost to achieve the same objective.

Experimental Full-Scale Test Cell Optimizing for Research of Novel Concepts towards Climatically Active Solar Façade Design

2016 ◽  
Vol 861 ◽  
pp. 213-220 ◽  
Author(s):  
Miroslav Čekon ◽  
Richard Slávik ◽  
Karel Struhala ◽  
Marian Formánek
Keyword(s):  
Numerical Models ◽  
Test Methods ◽  
Full Scale ◽  
Test Cell ◽  
Full Scale Test ◽  
Climate Conditions ◽  
Outdoor Climate ◽  
Research Activities ◽  
Building Components ◽  
Scale Test

The passive solar test facilities have recently been created in many research centers all over the world to analyse dynamic outdoor phenomena on buildings and their components. The main objective of these research activities is primarily to evolve a methodology, improve test methods, validate numerical models and measure real thermodynamic properties of building components under outdoor climate conditions. An integration of advanced material solutions into buildings need to be investigated within specific conditions related specifically to outdoor test methods. A research project on Contemporary concepts of climatically active solar facades at the Brno University of Technology does have an ambition to create an experimental full-scale test cell for research of thermal aspects in progressive advances of future solar façade concepts exposed to the real climate conditions. This paper describes the design optimization phase preceding the test cell assembly. This phase includes the analysis of energy and thermal properties based on parametric study features. Computer simulations based on finite element and volume methods are involved in the optimization process. The proposed optimized test cell design is confronted with parametrization of typical thermal aspects to present final test cell demonstration.

scholarly journals On the feasibility of watertight face-sealed window-wall interfaces

2019 ◽  
Vol 282 ◽  
pp. 02015
Author(s):  
Stéphanie Van Linden ◽  
Nathan Van Den Bossche
Keyword(s):  
Laboratory Experiments ◽  
Building Envelope ◽  
Water Infiltration ◽  
Test Results ◽  
Full Scale Test ◽  
Structural Insulated Panels ◽  
Building Components ◽  
Scale Test ◽  
Wood Frame ◽  
Frame Construction

Watertightness is still a major source of concern in the performance of the building envelope. Even very small deficiencies can cause a significant amount of water leakage which may result in structural degradation or malfunctioning of the insulation. The risk of water infiltration is highest at joints between different building components and in particular at the window-wall interface due to the complexity of these joints. This paper focuses on the performance of different solutions to ensure the watertightness of the window-wall interface, e.g. self-adhesive foils, liquid applied coatings, prefabricated frames, self-expanding sealing strips. The performance of these solutions is evaluated for different wall assemblies, i.e. ETICS, masonry, structural insulated panels and wood-frame construction. Laboratory experiments were conducted on a full-scale test setup with a window of 1,01 m high and 0,56 m wide. Test results showed that it is not evident to obtain watertight face-sealed window-wall interfaces without an additional airtight layer or drainage possibilities. Water ingress was often recorded at lower pressure differences.

scholarly journals Numerical modelling of a hemp concrete wall

2019 ◽  
Vol 85 ◽  
pp. 08003 ◽  
Author(s):  
Georges Costantine ◽  
Chadi Maalouf ◽  
Tala Moussa ◽  
Guillaume Polidori ◽  
Elias Kinab
Keyword(s):  
Building Materials ◽  
Moisture Transfer ◽  
Numerical Study ◽  
Object Oriented ◽  
Hysteresis Phenomenon ◽  
Energy Costs ◽  
Concrete Wall ◽  
Heat And Moisture ◽  
Account Heat ◽  
Indoor And Outdoor

In a global warming context associated to the abuse of energy consumption, actual researches focus more and more on reducing energy costs in the building sector. This target could be achieved by using innovative building materials, such as hemp concrete, due to its positive impacts on thermal and environmental levels. The aim of this work is to carry out a numerical study of a hemp concrete wall subjected to several indoor and outdoor conditions of temperature and relative humidity using the program object oriented SPARK. The hygrothermal behaviour of the wall is investigated taking into account heat and moisture transfer within the wall as well as hysteresis phenomenon between the sorption and desorption curves and their temperature dependency.

scholarly journals Methodological Proposal for the Development of Insurance Policies for Building Components

CivilEng ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 1-9
Author(s):  
Miguel Macedo ◽  
Jorge de Brito ◽  
Carlos Oliveira Cruz ◽  
Ana Silva
Keyword(s):  
Prediction Models ◽  
Methodological Approach ◽  
Insurance Coverage ◽  
Building Envelope ◽  
Premature Failure ◽  
Risk Premiums ◽  
Insurance Policies ◽  
Different Types ◽  
Building Components ◽  
Structured Approach

Insurance is a growing economic activity within the construction sector. Homes and buildings are perhaps the most important investment an individual makes in his/her lifetime. Nevertheless, the market for insurance coverage policies applied to the building envelope is in an embryonic stage, mainly due to the lack of knowledge in terms of risk and costs associated to the failure of these elements. This study provides an innovative and methodological approach to the development of an insurance product that targets the obsolescence of building components. In defining a structured approach to the design of insurance policies for buildings, the use of the service life prediction models proposed in this study allows establishing different types of insurance policies with different risk premiums and evaluating different losses and risks accepted by the owners, thus promoting the increase of the patrimonial value of the asset and reducing the risk of premature failure and the uncertainty of the costs of maintenance during its life cycle.

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