Revising the definition of anthropogenic heat flux from buildings: role of human activities and building storage heat flux
Revising the definition of anthropogenic heat flux from buildings: role of human activities and building storage heat flux
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DOI：
10.5194/acp-2021-914
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发表时间：
2021-11
影响因子：
6.3
通讯作者：
Yiqing Liu;Zhiwen Luo;S. Grimmond
中科院分区：
文献类型：
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作者：
Yiqing Liu;Zhiwen Luo;S. Grimmond
摘要。建筑物是人为热排放的主要来源，影响城市的能源使用和人类健康。建筑能耗与建筑人为热排放之间的差异幅度、时间差和量化程度较差。能源消耗（QEC）是广泛使用的建筑物人为热通量的代用指标（QF，B）。这里我们重新审视后者的定义。如果QF，B是建筑物内人类活动对室外环境的热量排放，则可以从有人居住和无人居住的建筑物之间的能量平衡通量变化中得出。我们的推导表明，QEC与QF，B之间的差异是由于人类活动引起的储热通量变化（∆So-uo）（即QF，B = QEC−∆So-uo）。利用建筑能量模拟软件EnergyPlus，我们计算了一个简化的隔离建筑在不同使用状态下的能量平衡通量（得到QF、B、QEC、∆So-uo）。由储热引起的QF、B和QEC之间的日模式差异不可忽略（例如，在中国北京，一年内每小时QF、B与QEC的比值在- 2.72和5.13之间变化）。负QF，B可以发生，因为人类活动可以减少建筑物的热辐射，但与大的储存热流相关。建筑操作（如开窗、使用暖通空调系统）不仅通过影响QEC也通过影响∆So-uo日剖面来改变QF，B。气温和太阳辐射是解释QF日变化的关键气象因子。我们的新方法可用于为未来人为热通量和建筑物储存热通量的参数化提供数据。很明显，城市的蓄热通量也可能受到居住者行为的影响。
Abstract. Buildings are a major source of anthropogenic heat emissions, impacting energy use and human health in cities. The difference between building energy consumption and building anthropogenic heat emission magnitudes and time lag and are poorly quantified. Energy consumption (QEC) is a widely used proxy for the anthropogenic heat flux from buildings (QF,B). Here we revisit the latter’s definition. If QF,B is the heat emission to the outdoor environment from human activities within buildings, we can derive it from the changes in energy balance fluxes between occupied and unoccupied buildings. Our derivation shows the difference between QEC and QF,B is attributable to a change in the storage heat flux induced by human activities (∆So-uo) (i.e., QF,B = QEC − ∆So-uo). Using building energy simulations (EnergyPlus) we calculate the energy balance fluxes for a simplified isolated building (obtaining QF,B, QEC, ∆So-uo) with different occupancy states. The non-negligible differences in diurnal patterns between QF,B and QEC caused by thermal storage (e.g. hourly QF,B to QEC ratios vary between −2.72 and 5.13 within a year in Beijing, China). Negative QF,B can occur as human activities can reduce heat emission from building but are associated with a large storage heat flux. Building operations (e.g., open windows, use of HVAC system) modify the QF,B by affecting not only QEC but also the ∆So-uo diurnal profile. Air temperature and solar radiation are critical meteorological factors explaining day-to-day variability of QF,B. Our new approach could be used to provide data for future parameterisations of both anthropogenic heat flux and storage heat fluxes from buildings. It is evident that storage heat fluxes in cities may also be impacted by occupant behaviour.