城市的热量和流动动力学:跨多种城市形态学的实验性比较研究
Yunpeng Xue1,2, Yongling Zhao3, KaMing Wai4
1Singapore-ETH Centre, ETH Zurich, Singapore.
概括
城市形态显著影响空气流和散热. 不同的建筑布局改变了热传输和通风,这对于管理城市气候和热岛效应至关重要.
科学领域:
- 城市气候学 城市气候学
- 环境流体动力学 环境流体动力学
- 大气科学 大气科学
背景情况:
- 城市地区表现出复杂的大气动态,受建筑配置的影响.
- 了解城市形态对流量,通风和散热的影响对于气候管理至关重要.
- 热浮力流与城市形状之间的相互作用尚未得到充分理解.
研究的目的:
- 在浮力效应下的3D城市模型周围研究热传输和流体流动.
- 分析城市形态学对非异热城市流动发展的影响.
- 在各种城市设计中量化通风和热去除性能之间的差异.
主要方法:
- 采用了同时粒子图像速度测量 (PIV) 和激光诱导光 (LIF) 测量.
- 使用模拟新加坡形态的三维参数城市模型.
- 在实验设置中考虑了浮力效应.
主要成果:
- 详细记录非热带城市流动的情况,包括热雾产生和浮力上游发展.
- 城市形态变化显著改变热量和流量机制,影响通风和热量去除.
- 通风速率及其波动显示出实质性的差异,分别增加了10.5倍和12.2倍.
结论:
- 城市形态在调节热驱动浮力流和热传输方面发挥着至关重要的作用.
- 通风效率和散热性能的显著差异与城市设计有关.
- 这些发现提高了对城市热力学和局部热效应的微气候影响的理解.
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