Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Cuce, Erdem(2)
Yayınlar
- MakaleYalnız künye2018Scopus SJRQ1Accurate and reliable U-value assessment of argon-filled double glazed windows: A numerical and experimental investigation
Cuce, Erdem
U-value assessment is a significant process to be able to evaluate the thermal insulation performance of building materials notably windows. About 60% of energy losses from building envelope is attributed to windows, hence accurate and reliable thermal resistance evaluation of glazed areas is of vital importance for a sensitive energy demand analysis of buildings. U-value assessment of windows is usually conducted through theoretical and numerical methods in literature. However, dwellers frequently complain about the insufficient thermal insulation performance of commercial glazing products when compared to the reported U-values in datasheets. This inconvenience arises from the lack of comprehensive experimental tests which simulate the actual operating conditions. Therefore, in this research, argon filled double glazed windows, which is one the most common fenestration products in market, is numerically and experimentally analysed in terms of U-value performance. Although computational fluid dynamics (CFD) analyses reveal that the U-value of the reference sample (4 mm pane + 20 mm argon + 4 mm pane) is 0.89 W/m(2)K, which is in good accordance with the theoretical data (0.80 W/m(2)K), it is observed from the environmental chamber tests that the U-value in simulated operating conditions is 1.25, 1.18 and 1.32 W/m(2)K for top, centre and lower positions of the window sample. The tests are repeated for accuracy verification, and the U-value is found to be 1.23, 1.18 and 1.31 W/m(2)K for the said points. In this respect, it is concluded that thermal bridges and edge effects play a key role in actual U-value performance of glazing products. Therefore, experimental performance figures are recommended to be utilised in energy demand analyses of buildings. (C) 2018 Elsevier B.V. All rights reserved.
AtıfWoS72OpenAlex90
İncele - MakaleYalnız künye2017Scopus SJRQ1Role of airtightness in energy loss from windows: Experimental results from in-situ tests
Cuce, Erdem
The rate of air leakage related energy loss from glazed areas is unequivocal especially in older and poorly installed windows. Therefore, in this research, a comprehensive experimental investigation is done to analyse the importance of air leakage on overall heat transfer coefficient (U-value) of conventional air filled double glazed windows. The tests are conducted in a typical UK dwelling of Nottingham fitted with traditional air filled double glazed windows. One sash of the test window is sealed internally with a special transparent cover to provide excellent airtightness whereas the second window sash is left as it is to represent the ordinary case. The experiments are conducted in April 2016, and dynamic co-heating test methodology is applied to evaluate the rate of enhancement in the U-value of airtight window sash. The results indicate that the airtight window sash has a notably lower U-value compared to the ordinary window sash due to the impact of airtightness and reverse heat flux during noon time owing to the greenhouse effect between transparent cover and internal glazing. The overall U-value of ordinary window sash is found to be 2.67 W/m2K, whereas it is 1.79 W/m2K for airtight window sash. It is observed that about 33% of reduction in heat losses can be achieved via airtight windows.
AtıfScopus60WoS59OpenAlex75
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