HAM Analysis of Selected Woodenframed Walls Pavol DURICA

HAM Analysis of Selected Wooden-framed Walls Pavol DURICA, Veronika KABATOVA, Peter JURAS, Jan RYBARIK Department of Building Engineering and Urban Planning, Faculty of Civil Engineerig, University of Zilina

Introduction § The Department of building engineering and urban planning (University of Zilina) is dealing with the wooden structures for long time. Its laboratories and equipment are being constantly upgraded to better conduct research in the area of coupled heat-moisture transport in the building envelopes. Realized long-term measurements are compared and evaluated with help of simulation made with WUFI software. § In this paper are evaluated two selected walls with different orientation and similar composition. Evaluation is focused on the temperature and relative humidity courses during the winter and spring time period. Measured courses are compared with HAM simulation. Also the non-steady U-value courses are shown. Download full paper at www. cesb. cz/19/8888 2205

Pavilion research § An expanded pavilion laboratory was launched at UNIZA in 2016 § Real outdoor climate, changeable indoor climate § Two experimental walls § South orientation § East orientation § Every wall has five different wall structure § There is an air conditioner in the room § The walls differs with thermal insulation, outdoor surface, use of vapour barrier EAST SOUTH Download full paper at www. cesb. cz/19/8888 2205

Pavilion research EAST orientation SOUTH orientation Download full paper at www. cesb. cz/19/8888 2205

Selected diffusely open structures Table 1. Material properties of used materials. Material Description d (m) λ (W/(m. K)) ρ c (J/(kg. K)) (kg/m 3) μ (-) Silicone plaster Weber 0 R 1 E, light beige 0. 0020 0. 86 1600 920 130 Glass fibre Blown-in insulation - Insulfit 0. 22 00. 043 35 940 1 Glass fibre Façade board - Clima 0. 1 0. 034 148 1030 1 Sandwich insulation Facade board (20 mm basalt fiber + 80 mm graphite polystyrene board) Twinner 0. 1 0. 033 25 1100 30 Phenolic insulation Kingspan Kooltherm K 5 0. 040 0. 021 35 1400 35 OSB board 3 0. 012 0. 13 650 1700 50 Download full paper at www. cesb. cz/19/8888 2205

Boundary condition used in simulation § Program for simulation – WUFI Pro 5. 1 § Exterior § Actual climatic conditions in the city of Zilina § Selected week in 2018 – March 2 to 7 § The lowest temperature was -12, 7°C on March 4, 2018 at 08: 00 § Average relative humidity was about 60% § Interior § Constant temperature 20°C § Constant relative humidity 50% Download full paper at www. cesb. cz/19/8888 2205

Comparison of experimental measurements and simulations S 1 U = 0, 10 W/(m 2 K) S 2 U = 0, 09 W/(m 2 K) § Graphically compared experimental measurement results with simulated results of the experimental wall fragment section during one chosen week Download full paper at www. cesb. cz/19/8888 2205

Heat transfer coefficient wall „S 1“ and „S 2“ § Figure shows the progress of the heat transfer coefficient of the two wall fragments. For wall composition „S 1“ the average coefficient of heat transfer is 0, 149 W/(m 2 K). Second wall structure „S 2“ has an average heat transfer coefficient of 0, 15 W/(m 2 K). Download full paper at www. cesb. cz/19/8888 2205

Selected experimental measurements of temperature and relative humidity South orientation 12. 10. 2018 – 18. 10. 2018 East orientation Download full paper at www. cesb. cz/19/8888 2205

Conclusion § This study pointed to a small temperature difference in two similar experimental wall fragments. The temperatures through the wall structure are similar. In some positions, higher temperature differences are observed. This is due to the different thermal insulation and heat-accumulation properties of the materials that have been used in the sandwich panels of wooden buildings. It also contains the passages of the heat transfer coefficients in the compared constructions. § Comparison of the measured parameters courses in the pavilion research and its simulation showed a significant match, which can be used in further research in variation of different boundary conditions in parametric studies. § Approximate agreement of heat transfer coefficient between theoretical value and non-stationary value from pavilion measurements was found. Download full paper at www. cesb. cz/19/8888 2205

Conclusion § The favorable temperature and humidity regimes for both diffuse open tracks and their suitability for almost zero energy building needs were confirmed. § The heat transfer coefficients in the compared wall compositions showed markedly non-steady courses. This could be further used to calculate more precisely heat loss through the building envelopes based on the timber framed walls. § Compare the same structure with different orientations: - in the winter, lower surface temperatures at the eastern orientation versus souther orientation - summer - the south facing wall has layers in the outer zone higher temperatures than outdoor temperatures § In the selected time periods, the selected compositions confirmed suitability for the realization of timber framed structures in passive buildings in terms of heat and moisture transport. Download full paper at www. cesb. cz/19/8888 2205

Conclusion § A year-round analysis of the measurements provides information on the behavior of selected sandwich wood walls exposed to real climate conditions. § These laboratory measurements together with the simulations will be later verified by testing on samples taken in the climate chamber. Due to the different types of materials used and their combinations, it is possible to observe and compare their behaviour under the same boundary conditions from the exterior as well as from the interior. § The results of the pavilion research confirmed the favorable thermal-humidity regime of the selected structures in the area of thermal bridges and the installation of supporting elements in the walls. § The results of long-term experimental measurements will become part of a significant database of thermal-moisture characteristics of embedded materials. Download full paper at www. cesb. cz/19/8888 2205

Thank you for your attention! Veronika Kabatova veronika. kabatova@fstav. uniza. sk Scan QR or download full paper at www. cesb. cz/19/ 2205