建筑冷热电联供(building combined cooling heating and power,BCCHP)系统具有显著的经济、环境和能效耦合特性,评估BCCHP系统的综合性能表现对于促进系统协调发展具有重要意义。该文基于系统的能量结构,构建多气候区BCCHP系统多准则...建筑冷热电联供(building combined cooling heating and power,BCCHP)系统具有显著的经济、环境和能效耦合特性,评估BCCHP系统的综合性能表现对于促进系统协调发展具有重要意义。该文基于系统的能量结构,构建多气候区BCCHP系统多准则评估框架。对区域气候条件特征和建筑类型特征下的建筑负荷演化机理展开分析;采用主观赋权和客观赋权相结合,基于最小鉴别信息原理得到评估指标综合权重;并通过前景理论和灰色关联分析法改进优劣解距离法(technique for order preference by similarity to an ideal solution,TOPSIS)方法。结果表明,成本节约率、能源利用率和可再生能源渗透率是BCCHP系统综合表现的关键体现,气候条件特征主要影响的经济效益,建筑类型特征影响系统的环境表现和能效表现。与其他3种评估方法相比,该文提出的多气候区BCCHP系统多准则评估框架具有良好的样本排序鲁棒性和更优的样本区别能力。展开更多
Indoor air quality and thermal comfort are important features of indoor environment. In this paper, a numerical simulation based on the k-ε model of CFD is used to analyze factors such as loading, exterior-protected ...Indoor air quality and thermal comfort are important features of indoor environment. In this paper, a numerical simulation based on the k-ε model of CFD is used to analyze factors such as loading, exterior-protected construction, blowing-in rate that play an important role in the temperature field and airflow field of the displacement ventilation system. Exterior-protected construction has little influence on indoor temperature distribution of displacement ventilation systems and the influence is limited only in a small area near the external wall when the indoor heat source is the main cooling load.The height of a room has little influence on indoor temperature field, and the temperature gradient of active region is basically unchanged. In the system combined with a displacement ventilation system and a cooling system, the height also has little influence. When the cooling load is high,the indoor heat source creates a strong convective plume, which will make the average indoor air age lower, the ventilation efficiency higher and the elimination of pollutant easier. Air supply rate plays an important role in displacement ventilation systems. The increase of air supply rate that can be realized by increasing the air supply velocity and enlarging the area of air inlet will increase the mass capability of the system and diminish the vertical temperature gradient. From the comparison between simulations and experiments, it is concluded that this simulation are creditable.展开更多
文摘建筑冷热电联供(building combined cooling heating and power,BCCHP)系统具有显著的经济、环境和能效耦合特性,评估BCCHP系统的综合性能表现对于促进系统协调发展具有重要意义。该文基于系统的能量结构,构建多气候区BCCHP系统多准则评估框架。对区域气候条件特征和建筑类型特征下的建筑负荷演化机理展开分析;采用主观赋权和客观赋权相结合,基于最小鉴别信息原理得到评估指标综合权重;并通过前景理论和灰色关联分析法改进优劣解距离法(technique for order preference by similarity to an ideal solution,TOPSIS)方法。结果表明,成本节约率、能源利用率和可再生能源渗透率是BCCHP系统综合表现的关键体现,气候条件特征主要影响的经济效益,建筑类型特征影响系统的环境表现和能效表现。与其他3种评估方法相比,该文提出的多气候区BCCHP系统多准则评估框架具有良好的样本排序鲁棒性和更优的样本区别能力。
文摘Indoor air quality and thermal comfort are important features of indoor environment. In this paper, a numerical simulation based on the k-ε model of CFD is used to analyze factors such as loading, exterior-protected construction, blowing-in rate that play an important role in the temperature field and airflow field of the displacement ventilation system. Exterior-protected construction has little influence on indoor temperature distribution of displacement ventilation systems and the influence is limited only in a small area near the external wall when the indoor heat source is the main cooling load.The height of a room has little influence on indoor temperature field, and the temperature gradient of active region is basically unchanged. In the system combined with a displacement ventilation system and a cooling system, the height also has little influence. When the cooling load is high,the indoor heat source creates a strong convective plume, which will make the average indoor air age lower, the ventilation efficiency higher and the elimination of pollutant easier. Air supply rate plays an important role in displacement ventilation systems. The increase of air supply rate that can be realized by increasing the air supply velocity and enlarging the area of air inlet will increase the mass capability of the system and diminish the vertical temperature gradient. From the comparison between simulations and experiments, it is concluded that this simulation are creditable.
