Studies on building layout for effective cross-ventilation

为了更好地利用交叉通风，对建筑物内部和周围的湍流气流进行了数值模拟和风洞试验。湍流的数学模型采用K-e 2方程模型。主要研究结果如下：(1)高层建筑周围气流的数值模拟结果与串联式热线风速仪在风洞试验中测量的整个模拟区域内的风速矢量分布吻合较好。(2)两房间窄小空间面墙风压系数大于单间侧壁风压系数。当屋间距越窄时，墙内风压的变化越大。(3)在所有风向情况下，当建筑覆盖率较大时，规则排列低层住宅各墙体风压系数绝对值均较小，接近于0。(4)高层建筑模型对低层住宅模型墙体风压的影响越大，低层住宅模型周围建筑覆盖率为25%时，高层建筑模型对墙体风压的影响越大。(5)高层建筑模型的迎风面低层住宅模型的风压系数越大，背风面低层住宅模型的风压系数越小。(6)为了更好地分析模型建筑从外部向内部连续流动的空气现象——交叉通风，尝试了采用局部细化技术的数值模拟方法。(7)交叉通风的估计需要模型建筑所有开口的总压降系数，因为通过室内空间的交叉通风的气流保存了它的运动学能量。传统方法基于静压差和开口处排出系数计算的通风量比实际交叉通风量小19-38%。(8)模型建筑入口口和出口口的总压降系数均小于1.0，后者约为前者的一半。相同形状的隔板位置不同，其开口处的总压降系数变化较大。特别是当隔墙被设置为交叉通风的屏障时，它是大的。少

Several cases of numerical simulation and wind tunnel tests of turbulent air flows in and around buildings were carried out for better utilization of cross-ventilation.k-e 2-equation model is adopted as a mathematical model of turbulence. The main results are summarized as follows : (1) The result of numerical simulation of an air flow around a high-rise building indicates good agreement with the distribution of wind velocity vectors in the whole simulation area measured by a tandem-type hot wire anemometer in a wind tunnel test. (2) The wind pressure coefficients on the walls facing to a narrow space between two houses are larger than those on a side wall of a single house. When the inter house gap is narrower, the change of the wind pressure in the wall is greater. (3) The absolute values of wind pressure coefficients on all the walls of regularly aligned low-rise houses are smaller and close to 0, when the building coverage ratio is larger in all the cases of wind direction. (4) The … More influence of a high-rise building model on the wind pressure on the walls of low-rise house models which are aligned regularly with a building coverage ratio of 25% around the building model becomes greater, when the building model is higher. (5) The wind pressure coefficients of low-rise house models located in the windward side of a high-rise building model are larger and those in the leeward side are smaller, when the building model is higher. (6) Numerical simulation methods employing partial refine technique are attempted successfully for the better analysis of cross-ventilation which is a continuous air flow phenomenon from the outside to the inside of a model building. (7) The estimate of a cross-ventilation rate needs total pressure drop coefficients at all the openings of a model building, because the air flow by cross-ventilation passing through the indoor space conserves its kinematic energy. The ventilation rates calculated by the conventional method based on static pressure differences and discharge coefficients of openings are smaller than actual cross-ventilation rates by 19-38%. (8) The total pressure drop coefficients at the inlet opening and that at the outlet opening of a model building are smaller than 1.0, and the latter is about a half of the former. The total pressure drop coefficients at the openings of partitions change greatly by the position of the partitions of the same shape. Especially, it is large when the partition is located to be a barrier of cross-ventilation. Less