Investigation of thermal performance of newly multilayer wall/roof constructions for low-carbon buildings

Abstract

Increasing concerns about energy consumption for heating and cooling of buildings have made it necessary to improve the thermal performance of building materials. However, in addition to using materials with high insulation characteristics, an accurate calculation of the capacities of the heating and cooling systems is also an important factor in ensuring high energy efficiency for low-carbon buildings. The devices will not be selected at capacities larger than the capacities that should be on this point and energy wastage will be prevented. To achieve this goal, in this study, investigations are carried out to produce new concrete types with high thermal insulating characteristics. Besides, many new concrete wall and roof samples were produced with different types of aggregates at different volume ratios and their thermophysical characteristics are tested in accordance with ASTM and EN standards. To estimate the thermal performance of produced samples, a periodic solution method, the Complex Finite Fourier Transform technique, is developed by using thermophysical characteristics data of those structures. The results showed that the daily heat gain values were calculated as 65.909 W/m2 for the EPC50 wall and 11.324 W/m2 for the PC40-EPC60 wall with 20 cm thicknesses.

Keywords

• Low carbon buiilding,
• concrete,
• heat gain,
• thermophysical cjaracteristics,
• complex finite Fourier transform technique.

References

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