The introduction of daylight can improve buildings’energy efficiency and bring benefit to occupant satisfaction.However,the introduction of daylight may accompany with excessive heat.Properly counterbalancing the ene...The introduction of daylight can improve buildings’energy efficiency and bring benefit to occupant satisfaction.However,the introduction of daylight may accompany with excessive heat.Properly counterbalancing the energy consumption of air conditioning and lighting systems owing to the entry of daylight is a critical control target of dynamic shading adjustment in cooling season.Most dynamic shading control strategies in use only consider one single system.Additionally,for advanced control mode like performance-based control,the predictive model usually only examines the instantaneous effect of energy performance to determine the shading adjustment state,unable to quantify the overall influence of shading adjustment state on building energy consumption.In order to address this issue,special consideration is given to calculating the cumulative contribution of heat gains to cooling load in this study.An overall energy-efficient shading control metric is proposed and used as basis to develop optimized dynamic shading control strategy.An application example demonstrates that the SGR-Optimal control strategy can further save energy by 21.8%~38.8%when compared to the Rule-based control strategy,thus allowing a better exploration of the energy efficiency potential of daylight measure.展开更多
The complete description of outdoor luminous and thermal environment is the basis for daylight utilization design with simulation tools.Nevertheless,Typical Meteorological Year(TMY)and generation method specifically d...The complete description of outdoor luminous and thermal environment is the basis for daylight utilization design with simulation tools.Nevertheless,Typical Meteorological Year(TMY)and generation method specifically developed for the energy simulation of daylight-utilized buildings is still unavailable currently.Luminous environment parameters have not been taken into consideration in existing TMY generation methods.In this study,the feasibility of existing TMY generation process has been examined.A generic office model implementing sided window daylighting is established.Historical meteorological data of Hong Kong region from 1979 to 2007 have been collected and three existing weighting schemes are applied during the Typical Meteorological Month(TMM)selection procedures.Three TMY files for Hong Kong are generated and used to conduct integrated Climate-Based Daylight Modeling and building energy simulation.The result demonstrates that,on annual basis,the energy consumption results obtained from the generated TMY files are in good agreements with the long-term mean annual value.The maximum deviation of annual energy consumptions for the generated TMY files is only 1.8%.However,further analysis on monthly basis shows that all the three generated TMY files fail to fully represent the long-term monthly mean level.The maximum deviation of monthly energy consumptions for the generated TMY files can reach up to 11%.As the energy performance daylight utilization is subject to weather change,analysis on daily and monthly energy level is important,especially during design stage.The deficiency of existing TMM selection process and TMY generation method indicates the necessity to develop a corresponding typical weather data input with finer resolution for the energy simulation of daylight-related buildings.展开更多
Thermal energy storage recycled powder mortar(TESRM)was developed in this study by incorporating paraffin/recycled brick powder(paraffin/BP)composite phase change materials(PCM).Fourier transform infrared and thermogr...Thermal energy storage recycled powder mortar(TESRM)was developed in this study by incorporating paraffin/recycled brick powder(paraffin/BP)composite phase change materials(PCM).Fourier transform infrared and thermogravimetric analysis results showed that paraffin/BP composite PCM had good chemical and thermal stability.The onset melting temperature and latent heat of the composite PCM were 46.49°C and 30.1 J·g−1.The fresh mortar properties and hardened properties were also investigated in this study.Paraffin/BP composite PCM with replacement ratio of 0%,10%,20%,and 30%by weight of cement were studied.The results showed that the static and dynamic yield stresses of TESRM were 699.4%and 172.9%higher than those of normal mortar,respectively.The addition of paraffin/BP composite PCM had a positive impact on the mechanical properties of mortar at later ages,and could also reduce the dry shrinkage of mortar.The dry shrinkage of TESRM had a maximum reduction about 26.15%at 120 d.The thermal properties of TESRM were better than those of normal mortar.The thermal conductivity of TESRM was 36.3%less than that of normal mortar and the heating test results showed that TESRM had good thermal energy storage performance.展开更多
文摘The introduction of daylight can improve buildings’energy efficiency and bring benefit to occupant satisfaction.However,the introduction of daylight may accompany with excessive heat.Properly counterbalancing the energy consumption of air conditioning and lighting systems owing to the entry of daylight is a critical control target of dynamic shading adjustment in cooling season.Most dynamic shading control strategies in use only consider one single system.Additionally,for advanced control mode like performance-based control,the predictive model usually only examines the instantaneous effect of energy performance to determine the shading adjustment state,unable to quantify the overall influence of shading adjustment state on building energy consumption.In order to address this issue,special consideration is given to calculating the cumulative contribution of heat gains to cooling load in this study.An overall energy-efficient shading control metric is proposed and used as basis to develop optimized dynamic shading control strategy.An application example demonstrates that the SGR-Optimal control strategy can further save energy by 21.8%~38.8%when compared to the Rule-based control strategy,thus allowing a better exploration of the energy efficiency potential of daylight measure.
基金supported in part by grants from Science and Technology Support Carbon Emission Peak and Carbon Neutralization Special Project of Shanghai 2021“Science and Technology Innovation Action Plan”[grant numbers 21DZ1208400].
文摘The complete description of outdoor luminous and thermal environment is the basis for daylight utilization design with simulation tools.Nevertheless,Typical Meteorological Year(TMY)and generation method specifically developed for the energy simulation of daylight-utilized buildings is still unavailable currently.Luminous environment parameters have not been taken into consideration in existing TMY generation methods.In this study,the feasibility of existing TMY generation process has been examined.A generic office model implementing sided window daylighting is established.Historical meteorological data of Hong Kong region from 1979 to 2007 have been collected and three existing weighting schemes are applied during the Typical Meteorological Month(TMM)selection procedures.Three TMY files for Hong Kong are generated and used to conduct integrated Climate-Based Daylight Modeling and building energy simulation.The result demonstrates that,on annual basis,the energy consumption results obtained from the generated TMY files are in good agreements with the long-term mean annual value.The maximum deviation of annual energy consumptions for the generated TMY files is only 1.8%.However,further analysis on monthly basis shows that all the three generated TMY files fail to fully represent the long-term monthly mean level.The maximum deviation of monthly energy consumptions for the generated TMY files can reach up to 11%.As the energy performance daylight utilization is subject to weather change,analysis on daily and monthly energy level is important,especially during design stage.The deficiency of existing TMM selection process and TMY generation method indicates the necessity to develop a corresponding typical weather data input with finer resolution for the energy simulation of daylight-related buildings.
基金The financial support from the National Natural Science Foundation of China(Grant No.52078358)is gratefully appreciatedNational Key R&D Program of China(No.2022YFE0198300)the GCCRN Core Project 11 are highly acknowledged.
文摘Thermal energy storage recycled powder mortar(TESRM)was developed in this study by incorporating paraffin/recycled brick powder(paraffin/BP)composite phase change materials(PCM).Fourier transform infrared and thermogravimetric analysis results showed that paraffin/BP composite PCM had good chemical and thermal stability.The onset melting temperature and latent heat of the composite PCM were 46.49°C and 30.1 J·g−1.The fresh mortar properties and hardened properties were also investigated in this study.Paraffin/BP composite PCM with replacement ratio of 0%,10%,20%,and 30%by weight of cement were studied.The results showed that the static and dynamic yield stresses of TESRM were 699.4%and 172.9%higher than those of normal mortar,respectively.The addition of paraffin/BP composite PCM had a positive impact on the mechanical properties of mortar at later ages,and could also reduce the dry shrinkage of mortar.The dry shrinkage of TESRM had a maximum reduction about 26.15%at 120 d.The thermal properties of TESRM were better than those of normal mortar.The thermal conductivity of TESRM was 36.3%less than that of normal mortar and the heating test results showed that TESRM had good thermal energy storage performance.