Collaborative Research: Development of a Phase Doppler Interferometer for Characterization of Particle-Turbulence Interactions in Clouds

合作研究：开发用于表征云中粒子-湍流相互作用的相位多普勒干涉仪

• 批准号: 0321318
• 负责人: Patrick Chuang
• 金额: --
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0321318&HistoricalAwards=false
• 关键词: Collaborative; Research; Development; Phase; Doppler

This grant supports the development of a phase Doppler interferometer (PDI) to observe the interaction of fine-scale turbulence and droplets in clouds. The scientific goal is to evaluate the extent to which turbulence influences collisions and coalescence, the processes whereby cloud droplets can interact with each other and grow to produce rain. Phase Doppler interferometry is an optical technique for measuring both the size of individual particles in the small volume defined by the intersection of two laser beams and the velocity of the particles relative to the instrument. The PI will work with Dr. Raymond Shaw of Michigan Technological University and Dr. William Bachalo of Artium Technologies to design and build a PDI especially suited for measuring cloud droplets. The plan is to develop an instrument capable of measuring the size, velocity, and spacing between droplets with diameters between 2 and 200 micrometers. Special attention will be given to problems common to optical detection devices, such as coincidence errors and the dependence of the volume sampled on the drop size. Testing the instrument in laboratory conditions, using existing wind tunnels and cloud chambers, will be an important part of validating its performance. Although the ultimate goal is to mount the PDI in an airplane for in-cloud measurements, the investigators will carry out initial experiments on laboratory clouds and in field deployments on towers or suspended from tethered balloons. There has long been speculation about the possible effects of turbulence on the collision-coalescence process of rain production. This instrument will fill an important gap in knowledge by actually observing the turbulent motions of cloud droplets at the small scales relevant for the process.

该赠款支持相位多普勒干涉仪（PDI）的开发，以观察细数湍流和云层中的液滴的相互作用。 科学的目标是评估湍流影响碰撞和聚结的程度，云滴可以彼此相互作用并生长以产生降雨的过程。 相多普勒干涉法是一种光学技术，用于测量由两个激光束的相交和颗粒相对于仪器相对于仪器的速度定义的小体积中的单个颗粒的大小。 PI将与密歇根州技术大学的Raymond Shaw博士和Artium Technologies的William Bachalo博士一起设计和构建PDI，特别适合测量云滴。 该计划是开发一种能够测量直径在2至200微米之间的液滴之间的尺寸，速度和间距。 将特别注意光学检测设备常见的问题，例如重合误差以及采样对液滴大小的体积的依赖性。 使用现有的风隧道和云室在实验室条件下测试仪器将是验证其性能的重要组成部分。 尽管最终的目标是将PDI安装在飞机中进行云中测量，但调查人员将在实验室云和塔塔上进行初步实验，或在塔楼上部署或悬挂在束缚气球上。 长期以来，人们一直在猜测湍流对雨水产量碰撞钙化过程的可能影响。 该仪器将通过实际观察与该过程相关的小尺度的云滴动作来填补知识的重要空白。