摘要
利用计算流体动力学(computational fluid dynamics,CFD)方法探究在风压热压混合作用下,于非均匀高度的城市建筑群中布置绿色屋面对城市街道峡谷内流场结构和通风能力的影响。针对参差型城市建筑群通风效果差、污染物滞留严重的问题,设计并比较多组绿色屋面布置方案。选取建筑高度参差比为30%的城市建筑形貌进行绿色屋面的环保可行性分析,并引入无量纲参数理查森数以模拟不同的气象条件;充分考虑15种绿色屋面的布置方案并进行综合分析,讨论了气流流场结构、污染物滞留时间、街谷内污染物浓度以及随热稳定性变化的情况等方面。数值模拟结果表明:绿色屋面的布置能够有效改善街道峡谷的通风换气能力,并优化街道峡谷内部的流场;对于参差型城市建筑,在建筑背风面和屋顶布置绿色屋面可使风压和热压达到最理想的协同效果,为改善城市生态、选择合适的绿化方式提供理论基础。
In this study,influence of green walls on ventilation characteristics of non-uniform buildings under dynamic-buoyancy hybrid effect is explored using hybrid computational fluid dynamics(CFD)methods.Aiming at the problems of poor ventilation performance and serious pollutant retention in uneven urban buildings,multiple groups of green wall layout schemes are designed and compared.This study selects urban buildings with a height difference ratio of 30%to analyze the environmental feasibility of green roofing,and the dimensionless Richardson number is introduced to simulate different meteorological conditions.15 kinds of green wall layout schemes are fully considered and comprehensively analyzed,and the structure of air flow field,the residence time of pollutants,the concentration of pollutants in street valley and the change of thermal stability are discussed.The numerical simulation results show that the arrangement of green roof can effectively improve the ventilation capacity of street canyons and optimize the flow field inside street canyons.For jagged urban buildings,the arrangement of green roofs on the leeward and roof of the building can achieve the most ideal synergistic effect of wind pressure and thermal pressure.This study provides a theoretical basis for improving urban ecology and selecting appropriate greening methods.
作者
张译丹
章伟晨
赵福云
郭江华
ZHANG Yidan;ZHANG Weichen;ZHAO Fuyun;GUO Jianghua(School of Power and Mechanical Engineering,Wuhan University,Wuhan 430072,China)
出处
《武汉大学学报(工学版)》
CAS
CSCD
北大核心
2024年第11期1598-1609,共12页
Engineering Journal of Wuhan University
基金
国家自然科学基金项目(编号:51778504)。
关键词
绿色屋面
风压热压耦合
通风性能优化
污染物扩散
green wall
wind-thermal coupling
ventilation performance optimization
pollutant dispersion