Studies on building layout for effective cross-ventilation

为了更好地利用交叉通风，采用k-ε 2方程模型作为湍流的数学模型，对建筑物内部及周围的湍流流动进行了数值模拟和风洞试验。主要研究结果如下：（1）对某高层建筑周围空气流动的数值模拟结果与风洞试验中采用串联式热线风速仪测得的整个模拟区域内的风速矢量分布吻合较好。(2)面对两间房屋之间狭窄空间的墙壁上的风压系数大于单个房屋的侧墙上的风压系数。当房屋间距较窄时，墙内风压的变化较大。(3)当建筑覆盖率较大时，规则排列的低层住宅在所有风向下，其所有墙体上的风压系数的绝对值均较小，接近于0。(4)的 关于我们 当建筑物模型较高时，高层建筑物模型对在建筑物模型周围以25%的建筑物覆盖率规则排列的低层房屋模型的墙壁上的风压的影响变得更大。(5)当高层建筑模型较高时，位于高层建筑模型迎风侧的低层房屋模型的风压系数较大，而背风侧的风压系数较小。(6)采用局部细化技术的数值模拟方法，成功地对模型建筑物内的横向通风这一连续气流现象进行了分析。(7)交叉通风量的估算需要模型建筑所有开口处的总压降系数，因为通过交叉通风穿过室内空间的空气流动保存了其动能。按传统方法根据静压差和孔口流量系数计算的通风量比实际交叉通风量小19- 38%。(8)模型建筑入口和出口处的总压降系数均小于1.0，且出口处的总压降系数约为入口处的一半。相同形状的隔板，其开孔处的总压降系数随隔板位置的不同而变化较大。特别是当隔板位于交叉通风的屏障时，它很大。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