POWRE: Laboratory Experiments of Wind-Raindrop Interactions

POWRE：风雨滴相互作用的实验室实验

• 批准号: 9753093
• 负责人: Ana Barros
• 金额: $ 7.1万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-10-01 至 2000-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9753093&HistoricalAwards=false
• 关键词: POWRE; Laboratory; Experiments; Wind; Raindrop

9753093 Barros The objective of this project is to improve upon existing empirical techniques to quantify rainfall impact by investigating the basic mechanisms of wind-raindrop interactions in the atmospheric boundary-layer over surfaces of varying slope, aspect and roughness. Rainfall impact on exposed surfaces is one of the most critical agents of deterioration of buildings and infrastructure, and a trigger mechanism of extended soil erosion. The research approach is to assess rainfall impact based on the kinetic energy and angle of impact of raindrops, which are determined by atmospheric conditions (average wind conditions and dynamic stability parameters such as buoyancy and turbulent shear) and the intrinsic properties of rainfall (intensity and raindrop size distribution). For this purpose, acoustic emission testing of rainfall impact will be conducted in the presence and absence of wind, while high-resolution photography will be used to study the pathways and transformations of raindrops moving through turbulent boundary-layers simulated in a large-scale wind tunnel. Ultimately, the goal is to establish a conceptual framework of the physics of wind-raindrop interactions to address a wide range of science and engineering problems, such as to estimate soil erodibility indices as a function of climate, or to define design criteria for building facades. The support provided by the POWRE program will be used for the acquisition of an acoustic measurement unit suitable to monitor the impact of rainfall at various locations simultaneously, and to conduct exploratory wind-tunnel experiments at the Saint Anthony Falls Hydraulic Laboratory, University of Minnesota. These experiments are essential to obtain the data necessary to perform an evaluation of the feasibility and potential success of the proposed research, before a comprehensive investigation to characterize the fate of raindrops in the atmospheric boundary layer can be pursued.

9753093 Barros 该项目的目标是通过研究不同坡度、坡向和粗糙度表面的大气边界层中风雨滴相互作用的基本机制，改进现有的经验技术来量化降雨影响。降雨对裸露表面的影响是建筑物和基础设施恶化的最关键因素之一，也是长期土壤侵蚀的触发机制。研究方法是根据雨滴的动能和撞击角度来评估降雨影响，而雨滴的动能和撞击角度是由大气条件（平均风况和浮力和湍流剪切等动态稳定参数）和降雨的固有特性（强度和雨滴尺寸分布）决定的。 为此，将在有风和无风的情况下进行降雨影响的声发射测试，同时将使用高分辨率摄影来研究雨滴穿过大型风洞模拟的湍流边界层的路径和转变。最终的目标是建立风雨相互作用物理学的概念框架，以解决广泛的科学和工程问题，例如估计土壤可蚀性指数作为气候的函数，或定义建筑外墙的设计标准。 POWRE 计划提供的支持将用于购买适合同时监测不同地点降雨影响的声学测量装置，并在明尼苏达大学圣安东尼瀑布水利实验室进行探索性风洞实验。在进行全面调查以表征大气边界层中雨滴的命运之前，这些实验对于获得评估拟议研究的可行性和潜在成功所需的数据至关重要。