Bubble Thermography Velocimetry for Urban Flow Field Characterization

Project Summary: It is projected that by 2050 70% of the worldĺs population will live in urban areas that will occupy only 1% of the Earthĺs land. The extreme size and density of urban populations demand improved scientific approaches to address urban meteorology challenges such as predicting and modeling extreme heat and rainfall, and severe air pollution. Existing observational tools, such as sonic anemometry and lidar, do not operate in the range of spatial scales that is most applicable to many urban meteorological applications, and they have very limited capabilities in capturing spatial variability in urban atmospheric flow. The proposed approach, bubble thermography velocimetry (BTV), is a flow field measurement technique capable of characterizing the distribution of wind velocity vectors in three-dimensional space and time. It measures spatial scales that are of immediate relevance to understanding, monitoring and modeling urban micrometeorology but largely absent from existing observational capabilities. This technique is expected to be exceptionally flexible with an outstanding performance-cost ratio. Our Phase I effort will include the development of a prototype system and data processing and analysis tools. Field tests will be performed to characterize the performance of BTV in terms of spatial resolution and velocity accuracy. The cost, deployability and applicability will also be assessed in Phase I. Commercial Applications and Other Benefits: With advantages in spatial resolution and performance- cost ratio, BTV is expected to be a significant addition and improvement to current meteorology observational networks. Upon successful development, BTV will be one of the most suitable tools for a range of urban micrometeorology applications, including urban heat management, pollutant and pathogen tracking, and Urban Air Mobility. Moreover, BTV will be a unique tool to support the modeling of greenhouse gas transport, leading to more effective and sustainable remediation for global warming.