Mold Growth Risk Analysis on the Surfaces of an Organic Building Structure Based on In Situ Monitoring

This article deals with the assessment of methodologies for water vapor condensation determination and mold growth risk analysis on the surfaces of an organic building structure based on in-situ monitoring, carried out on the structural elements of renovated roof truss above the greenhouse “Květná zahrada” in Kroměříž. The garden including the building is signed on the UNESCO Word Heritage List for its historical and architectonical value. The monitoring was focused on hygrothermal behavior of a particular attic area during winter term 2014 - 2015. The risks of water vapor condensation and mold growth were then analyzed on the basis of data obtained by the monitoring process. These also include measurement and output data accuracy is included as well. The Results were used as recommendation for a control system of forced ventilation in the monitored attic area.

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Methods for Determining Mold Development and Condensation on the Surface of Building Barriers

Buildings ◽

10.3390/buildings10010004 ◽

2019 ◽

Vol 10 (1) ◽

pp. 4 ◽

Cited By ~ 1

Author(s):

Aleksander Starakiewicz ◽

Przemysław Miąsik ◽

Joanna Krasoń ◽

Lech Lichołai

Keyword(s):

Water Vapor ◽

Vapor Condensation ◽

Mold Growth ◽

Vapor Pressures ◽

Climate Conditions ◽

Outdoor Climate ◽

Surface Condensation ◽

Water Vapor Condensation ◽

Calculation Results ◽

Temperature Factors

The article presents four equivalent methods for checking mold growth on the surface of building barriers and checking water vapor condensation on their surface. Each method applies to two parallel phenomena that may occur on a building barrier. The first method is to calculate and compare temperature factors. In the second method, the characteristic humidity in the room is calculated and compared. The third method is to calculate and compare the characteristic temperatures in the room. The fourth method is based on the calculation and comparison of characteristic water vapor pressures. Three boundary conditions are presented for each method and phenomenon: when a given phenomenon can occur, when it begins or ends, and when it does not occur. The presented methods systematize the approach to the problem of mold development and surface condensation. The presented calculation results relate to the selected building barrier functioning in specific indoor and outdoor climate conditions. The calculation results confirm the compliance of the presented methods in identifying the phenomenon of mold growth or condensation on the surface of the barrier. A graphical interpretation of the results for each method with periods of occurrence or absence of a given phenomenon is also presented.

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An Experimental Investigation of Water Vapor Condensation from Biofuel Flue Gas in a Model of Condenser, (1) Base Case: Local Heat Transfer without Water Injection

Processes ◽

10.3390/pr9050844 ◽

2021 ◽

Vol 9 (5) ◽

pp. 844

Author(s):

Robertas Poškas ◽

Arūnas Sirvydas ◽

Vladislavas Kulkovas ◽

Povilas Poškas

Keyword(s):

Heat Transfer ◽

Water Vapor ◽

Flue Gas ◽

Waste Heat Recovery ◽

Waste Heat ◽

Water Injection ◽

Vapor Condensation ◽

Base Case ◽

Water Vapor Condensation ◽

Condensing Heat Exchanger

Waste heat recovery from flue gas based on water vapor condensation is an important issue as the waste heat recovery significantly increases the efficiency of the thermal power units. General principles for designing of this type of heat exchangers are known rather well; however, investigations of the local characteristics necessary for the optimization of those heat exchangers are very limited. Investigations of water vapor condensation from biofuel flue gas in the model of a vertical condensing heat exchanger were performed without and with water injection into a calorimetric tube. During the base-case investigations, no water was injected into the calorimetric tube. The results showed that the humidity and the temperature of inlet flue gas have a significant effect on the local and average heat transfer. For some regimes, the initial part of the condensing heat exchanger was not effective in terms of heat transfer because there the flue gas was cooled by convection until its temperature reached the dew point temperature. The results also showed that, at higher Reynolds numbers, there was an increase in the length of the convection prevailing region. After that region, a sudden increase was observed in heat transfer due to water vapor condensation.

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Water vapor condensation on binary mixed substrates: A molecular dynamics study

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2021.122281 ◽

2021 ◽

pp. 122281

Author(s):

Zi-Jie Wang ◽

Shao-Yu Wang ◽

Dan-Qi Wang ◽

Yan-Ru Yang ◽

Xiao-Dong Wang ◽

...

Keyword(s):

Molecular Dynamics ◽

Water Vapor ◽

Vapor Condensation ◽

Mixed Substrates ◽

Water Vapor Condensation

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Water Vapor Condensation from Fossil Fuels and Tropical Volcanoes

Confronting Global Climate Change ◽

10.1201/9780429284847-2 ◽

2019 ◽

pp. 17-31

Author(s):

Mark Anglin Harris

Keyword(s):

Water Vapor ◽

Fossil Fuels ◽

Vapor Condensation ◽

Water Vapor Condensation

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INFLUENCE OF LIGHTWEIGHT FILLERS ON THE PERFORMANCE OF CEMENT-BASED SKIM COAT

Structure and Environment ◽

10.30540/sae-2020-001 ◽

2020 ◽

Vol 12 (1) ◽

pp. 5-11

Author(s):

MARCIN KUPIŃSKI ◽

KAROLINA STOBIENIECKA ◽

KAROL SKOWERA

Keyword(s):

Thermal Conductivity ◽

Thermal Conductivity Coefficient ◽

Pozzolanic Reaction ◽

Vapor Condensation ◽

Cement Matrix ◽

Capillary Absorption ◽

Mold Growth ◽

Expanded Perlite ◽

Water Vapor Condensation ◽

Effective Additive

Lightweight fillers are used in dry-mixed building mortars in order to improve thermal insulation properties, yield, and workability. In the case of thin layer products, used as a finishing layer, reduced thermal conductivity coefficient enables to restrain of water vapor condensation on walls – which inhibits mold growth. The aim of the study was to determine the influence of 4 types of lightweight fillers on the performance of cement-based skim coat – with emphasis on the economic aspect. Formulas reflecting typical commercial products were used. The dosage of different components -such as expanded perlite, glass and polymeric bubbles or expanded glass – was optimized for sufficient yield and workability, keeping the constant price of 1 kg of the final product. Mechanical parameters, capillary absorption coefficient, and thermal conductivity coefficient were determined. Observations by Scanning Electron Microscope revealed poor incorporation of polymer microspheres in the cement matrix, leading to loss of mechanical strength. With the addition of expanded glass, an increase of flexural and compressive strength thanks to the pozzolanic reaction was observed. Glass bubbles were found the most effective additive.

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