Effect of localized exterior convective heat transfer on high-rise building energy consumption
high-rise building, computational fluid dynamics, convective heat transfer coefficient, building energy simulation, EnergyPlus
The energy consumption analyses of high-rise buildings have some fundamental limitations that include the treatment of building size, changes in microclimate parameters with altitude, and the uncertainties associated with the existing building façade convective heat transfer coefficients correlations (CHTC). This study investigates the effects of these parameters on the energy consumption by individual rooms at a different location as part of a 100 m high-rise building, exposed to different weather conditions, having a different window-to-wall ratio. In the first part of the study, representative new-CHTC at the windward façade of the building is generated by using CFD simulations. In the second part of the study, comparative energy consumption assessment is carried out using the newly generated CHTC and other commonly used correlations by using EnergyPlus. The result shows that for high-rise building with 100% WWR exposed to a windy microclimate (such as Boston, MA), a deviation of 11.2% and 4.7% on annual heating and cooling energy consumption, respectively, have been observed. Further, the energy consumption of each room throughout the building height was also investigated to investigate the effect of building height. Compared to a room located at the mid-height (15th floor), the annual heating consumption on a room located at the 5th floor room was 7.8% lower and a room located on the 25th floor room the consumption was 7.6% higher. In summary, this study highlights the importance of accurate local CHTC generation to enhance thermal comfort in individual rooms and to optimize overall building energy consumption.
Tsinghua University Press
Meseret T. Kahsay, Girma Bitsuamlak, Fitsum Tariku. Effect of localized exterior convective heat transfer on high-rise building energy consumption. Build Simul, 2020, 13(1): 127–139.