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Description
This report documents the results of an empirical study to characterize science diaspora networks and their underlying organizations and to document how network managers characterize operational successes, challenges, future plans, and relations to science diplomacy.
ContributorsElliott, Steve (Author) / Butler, Dorothy (Author) / Del Castello, Barbara (Author) / Goldenkoff, Elana (Author) / Warner, Isabel (Author) / Zimmermann, Alessandra (Author)
Created2022-09-14
Description
Human exposure to extreme heat is becoming more prevalent due to increasing urbanization and changing climate. In many extreme heat conditions, thermal radiation (from solar to emitted by the surrounding) is a significant contributor to heating the body, among other modes of heat transfer. Therefore, accurately measuring radiative heat flux on a human body is becoming increasingly important for calculating human thermal comfort and heat safety in extreme conditions. Most often, radiant heat exchange between the human body and surroundings is quantified using mean radiant temperature, T_mrt. This value is commonly measured using globe or cylindrical radiometers. It is based on radiation absorbed by the surface of the radiometer, which can be calculated using a surface energy balance involving both convection and emitted radiation at steady state. This convection must be accounted for and is accomplished using a traditional heat transfer coefficient correlation with measured wind speed. However, the utilized correlations are based on wind tunnel measurements and do not account for any turbulence present in the air. The latter can even double the heat transfer coefficient, so not accounting for it can introduce major errors in T_mrt. This Thesis focuses on the development, and testing of a cost-effective heated cylinder to directly measure the convection heat transfer coefficient in field conditions, which can be used for accounting convection in measuring T_mrt using a cylindrical radiometer. An Aluminum cylinder of similar dimensions as that of a cylindrical radiometer was heated using strip heaters, and the surface temperature readings were recorded to estimate the convection heat transfer coefficient, h. Various tests were conducted to test this concept. It was observed that heated cylinders take significantly less time to reach a steady state and respond to velocity change quicker than existing regular-sized globe thermometers. It was also shown that, for accurate estimation of h, it is required to measure the outer surface temperature than the center temperature. Furthermore, the value calculated matches well in range with classic correlations that include velocity, showing proof of concept.
ContributorsGuddanti, Sai Susmitha (Author) / Rykaczewski, Konrad (Thesis advisor) / Vanos, Jennifer (Committee member) / Wang, Robert (Committee member) / Burke, Richard (Committee member) / Arizona State University (Publisher)
Created2023
Description
Urban centers worldwide face the escalating challenge of urban heat islands (UHIs), which exacerbate public health issues and energy consumption due to increased temperatures. This thesis focuses on the Phoenix metropolitan area, recognized for its high summer temperatures, to explore innovative computational strategies for mitigating urban heat through optimized tree placement. The research integrates high-fidelity microclimate modeling with advanced computational techniques to strategically position trees and enhance urban climate resilience. Utilizing the SOLWEIG and TreePlanter models, this study simulates the effects of tree planting on mean radiant temperature (MRT), crucial for thermal comfort in outdoor spaces. The models process geospatial data, including LiDAR and high-resolution thermal maps, to produce actionable insights for reducing urban temperatures. Results indicate that strategic tree planting significantly lowers MRT, enhancing urban livability and sustainability. This thesis contributes to urban planning by demonstrating how targeted greening interventions can alleviate the heat burden in cities, providing a replicable framework for other urban areas experiencing similar challenges.
ContributorsGarg, Shrey (Author) / Middel, Ariane (Thesis director) / Buo, Isaac (Committee member) / Barrett, The Honors College (Contributor)
Created2024-05