河谷城市多风向环境下行列式住区建筑外壁面对流换热模拟——以西宁市为例

Convection Heat Transfer on Outer Wall of Buildings in River Valley under Multi-wind Environment——A Case Study of Xining City

河谷城市低速多方向风环境下,行列式住宅的不同位置建筑外壁面对流换热强度不同。本文以西宁市为例,采用CFD模拟方法对该城市典型的行列式建筑群在冬季采暖期内不同风向的总体风环境下,不同位置建筑的对流换热强度进行了模拟。结果表明:本模拟的单体建筑的短边方向壁面比长边壁面对流换热强度高约10%,行列式建筑群正南北布置时内部的建筑比斜向布置时对流换热强度更小,建筑群规模越大,建筑的整体外壁面对流换热强度越小;西宁采暖期风条件下,建筑外壁面对流换热系数为3-5 W/(m^2·K);群体布局中角点位置的建筑对流热损失最大,其迎风立面的边缘部位换热最强应加强保温,单体建筑的短边壁面应尽量少开窗,减少凹凸。

In the low-speed multi-direction wind environment of a river valley city,the convective heat transfer intensity varies with the outer wall of buildings in different locations.In this context,the CFD numerical simulation was used to simulate the convective heat transfer intensity of typical buildings at different locations of Xining City when wind blew from different directions during the winter heating period.The results show that the convective heat transfer intensity of short side wall in a single building was about 10% higher than that of long side wall.The convective heat transfer intensity of interior buildings was smaller when the buildings were oriented north-south than when they were oriented diagonally.Larger buildings had smaller convective heat transfer intensity of exterior wall.Under the wind conditions in Xining during the winter heating period,the convective heat transfer coefficient of exterior wall was 3 - 5 W/( m^2·K).In the group layout,the buildings at the corner point had the greatest heat loss by convection.The heat transfer at the edge of windward facade was the strongest.