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BUILT & NATURAL ENVIRONMENT
Projects:  Urban Airshed Modeling The impact of the built environment on local wind speeds is poorly understood. Boundary layer wind speed profiles have been published for four normative terrains (ASHRAE 2005) but do not account for specifics of any given city or region. Wind-pressure coefficients for buildings are essential in modeling the potential benefit of natural ventilation but typically do not factor in the impact of neighboring buildings. More fine-grained, city-specific and long-term data are required in order to support modeling work that will inform policies that control urban development. An appropriate airflow measurement protocol will be developed and tested in a limited number (2-3) of urban areas. A combination of sensor arrays attached to test buildings and CFD and thermal modeling will be used to investigate airflows and convective heat transport in urban canyons. The study will be extended to thermal plumes associated with air conditioners, how these plumes are affected by local winds, and their influence on heat flows through the building envelope and on the efficiency of the air conditioners.
Contact PI: Leslie Norford
Interactions between the Built and Natural Environment This project will focus on measurements and modeling of the interconnected flows of energy (convective and radiative) between the built and natural environments. Research will be carried out in two main areas: 1) radiometric and photometric measurements and models; and 2) urban-heat-island measurements and models. Radiometric and photometric data will be obtained using a combination of stationary systems (rooftop mounted sky scanner, sun tracker and pyranometer)and wirelessly-linked mobile platforms (MODS system). The latter will enable comparative studies of daylight availability in the open field versus street canyons to identify the impact of the build environment on sky luminance. Climate parameters such as air temperature, moisture content, wind etc, will be collected to establish the current conditions and will be linked to urban-element data (building, pavement and greenery) to form an urban climatic mapping framework. The Tropical Green Cluster Thermal Time Constant (CTTC) model, to be validated with the measured data, will extend Swaid and Hoffman's CTTC (1990) to include the impact of tropical vegetation on urban temperatures and humidity.
 Increase in night-time temperatures in urban areas due to heat-island effects (Arizona State University)
Contact PI: Leslie Norford
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