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Evaporative misters have long been used in urban spaces for heat mitigation, yet their thermal stress impacts and optimal operating conditions have not been fully explored. To fill this gap, we develop a misting model and embed it into an urban canopy model for the first time. Our tests confirm that misters can considerably reduce maximum urban canyon air temperature (up to 17.5 °C) and human skin temperature (up to 0.48 °C) in a hot and dry city (Phoenix, AZ). They continue to effectively reduce thermal stress, albeit with half of the cooling benefits, in a hot and humid city (Houston, TX). These thermal stress impacts are contingent upon wind speeds: the optimal wind speeds generally fall within an intermediate range—from light air (with low mist flow rates) to a moderate breeze (with higher mist flow rates). We then incorporate misting into a broader comparison of blue cooling strategies, including irrigation (on vegetation) and sprinkling (on pavements). With abundant water resources, sprinkling on asphalt and misting are the most effective cooling solutions, particularly suitable for middays and late afternoons, respectively. To balance cooling benefits with limited water resources, we propose a thermostatic control scheme that can save at least 10.5 m3/day of water compared to continuous misting for a 100-m stretch of street, equivalent to the water demand of about 20 Phoenix residents. Notably, misting and sprinkling generate rapid cooling in under 10 min with sufficient flow rates, demonstrating their potential as fast activation measures during extreme heat emergencies. 

Understanding the thermal comfort and safety of diverse populations within indoor settings requires a quantitative understanding of the primary heat exchange pathways between occupants and their surroundings: radiation and free convection. Thus far, however, free convective heat transfer coefficients have only been determined for the average Western adult. To this end, we investigated how variation in body shape impacts free convection heat transfer using an experimentally validated numerical model. The multiphysics model was compared against experiments conducted using the thermal manikin ANDI (Advanced Newton Dynamic Instrument) in a climate-controlled enclosure across five air-to-skin temperature differences ranging from 4.9 to 13.9°C. The difference between measured and simulated heat fluxes for the whole body, and per anatomical region, was typically <5%, occasionally reaching 15–20%, for some body regions due to physical features not modeled in the virtual ANDI model. Using the validated model, we simulated free convection around a family, or diverse group, of virtual manikins representing the 1^stto 99^thpercentile body mass index (BMI) and height variation in the United States adult population. Our results show that the free convection heat transfer coefficient is independent of human sex and height but decreases slightly with increased BMI. However, the variation from the average manikin in the whole body and regional free convection coefficients with BMI was small, not exceeding 8% and 16%, respectively. Furthermore, our regression coefficients and exponents can be derived from the theorical correlation for free turbulent convection from a vertical plate, which also explains the observed independence of the heat transfer coefficient from the manikins’ height. Overall, these findings demonstrate the general applicability of using an average body shape in indoor thermal audits and/or overheating risk assessments to understand thermal comfort and heat stress. The results and valid application of the model support critical insights for human health, productivity, and well-being connected to heat and cooling in buildings.