Advanced Materials Research Vol. 1041

Abstract: This paper deals with measurements of wind-driven rain intensity in Meteorological garden of Slovak hydrometeorological institute and subsequent modelling of free standing wind-driven rain gauge in OpenFoam CFD simulation tool using Eulerian multiphase model instead of common used Langrangian particle tracking model.

Abstract: The paper presents an analysis of indoor temperature and relative humidity measurements in dwelling's bathroom. Obtained data are compared with those defined in technical standards and applied for assessment of building component from building physics point of view. These parameters are used for boundary condition at the evaluation level of building components and their values have significant influence on hygrothermal assessment. The example of building's component demonstrates analysis magnitude of differences between the calculation results applying standardized boundaries condition and monitored data based on in-situ measurements. Temperature and humidity measurements are applied for prediction of hygrothermal behavior of building’s component by HAM algorithm. Finally, results from analysis presents the penetration depth of moisture increasing at surface caused by moisture peaks in internal environment of bathroom.

Abstract: This paper focuses on the analysis of the roof overhang detail performed by using rafter within above-rafter thermal insulation system. Close attention is paid especially to course of temperatures and the moisture condition of the rafter which goes continuously through the building envelope from interior to exterior. Both simplified thermo-technical calculations results and the results from long-term experimental measuring performed on a real building are presented and compared here.

Abstract: Calculation of heat losses of buildings according to European standard EN ISO 10211 and Czech standard ČSN 73 0540 is simplified to one-dimensional time-steady heat conduction through the building construction in direction of the largest temperature gradient. This simplification of the calculation is incorrect in case of complex geometry. Calculation according to norm takes into account this inaccuracy and uses Linear Thermal Transmittance Ψ [W/(m·K)] in 2D geometry or Point Thermal Transmittance χ [W/(m2·K)] in the 3D geometry as a calculation correction. This contribution is focused on detailed calculation of linear thermal transmittance in case of contact external peripheral wall and plastic window frame. Results of two-dimensional transient numerical simulation show unsteady linear thermal transmittance in time and dependence on solar radiation. All of these variable boundary conditions can be easily simulated in the software CalA as well as complex geometry.

Abstract: In this paper, the most common approximate thermal conductivity calculation methods were compared through Hungarian soil samples with laboratory measurement results and the representative values of EN ISO 13370:2007. Based on the results, the soil’s thermal conductivity can be estimated using the modified Johansen method for higher sand containing samples, and de Vries’s method for the high silt and clay containing samples. In the light of the test results, two new methods were developed, which can be used for sandy clay silt samples. These gave almost identical results compared to the measured values and were also more accurate than the other estimations in the analysed situations.

Abstract: The paper deals with the construction of walls of log wood houses of Canadian type in terms of thermal insulation, with the focus shifted onto the comparison of alternative structural solutions of such walls. The main aim of the research done was to assess the different Canadian type massive log wood walls, with various thermally insulating materials placed between the logs. The computer simulations of wall models were done in ANSYS software. Massive wooden walls unfortunately do hardly meet today's ever increasing requirements given for thermal resistance, heat conductivity and heat losses of a building, since the bed joints are weakened and also because of the thermal conductivity of wood itself. Thus, mainly the contact surface temperature was observed, which also became one of the evaluation factors describing the quality of construction.

Abstract: Real dynamic boundary conditions and initial condition has to be taken into an account when simulations need to be done. The most helpful are in situ measurement facilities with climate monitoring. Indoor environment operation modes with different air temperature and relative humidity made indoor boundary conditions. Measured weather data are used to create complete boundary conditions for the research locality. Initial condition of masonry water profile is set up. The initial and boundary conditions are considered for an individual locality simulation proposes.

Abstract: This paper discusses theory and application of microwave radiation and experimental optimization of microwave radiation to eliminate moisture content in wood elements. Owing to its properties, microwave radiation has been used in the construction industryin modern times, in particular to dry wet masonry of buildings. Effects of electromagnetic radiation on building structures lead to relatively sharp decreases in moisture content from damp building structures or elements. The influence of electromagnetic radiation on building structures lead to oscillation of water molecules contained in the material, which cause a phase transformation of water into vapour. Consequently, the vapour evaporates from the moist material, thereby drying the element exposed to radiation.The article describes experiments carried out at the Faculty of Civil Engineering of the Faculty of Technology in Brno that demonstrate successful decrease of water content in building materials using microwave radiation. First, the understanding of microwave radiationwill be discussed.Following an analysis of research results an optimum intensity of microwave radiation sources as well as the necessary length of the irradiation of microwave radiation have been determined with respect to the particular type of building material and the success rate of elimination of moisture.

Abstract: Solar radiation is the main source of heat gains during the summer period. The most exposed non-translucent structure of the building is the roof. Material characteristics of roof tiles are able to influence the upper surface temperature and also the thermal performance of the whole roof structure. The aim of this article is comparison of the highest temperatures of roofing tiles reached by a summer day in accordance to their material characteristics. Data obtained from an in-situ measurement are compared with the values obtained by numerical calculation. The temperatures obtained by in-situ measurement are higher than thus earned by numerical calculation.

Abstract: The paper is oriented on the hygrothermal microclimate of residential interiors in reconstructed building. The questionnaire survey has showed significant increase in number of allergies, respiratory diseases and occurrence of fungi after reconstruction. In order to find causes, experimental measurements of hygrothermal microclimate were carried out. The long term high values of relative humidity were found out and the link with number of efficient natural ventilation was searched for. Ventilation once a day was usual, what was proved as insufficient. Dwellers were informed about right way and number of ventilation. Furthermore, measurements proved decrease of air humidity, but not sufficiently. It was proved that nobody was able to achieve recommended number of ventilation and almost all of them considered it annoying and unreal to sustain. The biggest problem was proved night 7 hour interval. Therefore allergic and respiratory problems were significant in the morning. In conclusions of paper is suggestion for solution of researched problem.