The negative health impacts of extreme heat exposure can be mitigated by incorporating hyperlocal biometeorological observations into heat action planning, emergency responses, and heat-reducing urban design. A significant portion of outdoor human heat exposure is radiative, but it is often overlooked due to the absence of affordable, accurate, and user-friendly sensors. We developed a two cylinder anemometer and radiometer (CARla) consisting of unheated and heated gray components, which quantifies wind speed and the total radiation absorbed by the human body.
View Article and Find Full Text PDFSweat evaporation is critical to human thermoregulation, but current understanding of the process on 20 μm to 2 cm scale is limited. To this end, we introduce a wind-tunnel-shaped ventilated capsule with an infrared window for simultaneous infrared sweat imaging and evaporation rate measurement. Implementing the capsule in pilot human subject tests suggests that the common assumption of sweat being an isothermal film is only valid when the evaporation rate is low and sweat forms puddles on the skin.
View Article and Find Full Text PDFExtreme heat is a current and growing global health concern. Current heat exposure models include meteorological and human factors that dictate heat stress, comfort, and risk of illness. However, radiation models simplify the human body to a cylinder, while convection ones provide conflicting predictions.
View Article and Find Full Text PDFAs populations and temperatures of urban areas swell, more people face extreme heat and are at increasing risk of adverse health outcomes. Radiation accounts for much of human heat exposure but is rarely used as heat metric due to a lack of cost-effective and accurate sensors. To this end, we fuse the concepts of a three-globe radiometer-anemometer with a cylindrical human body shape representation, which is more realistic than a spherical representation.
View Article and Find Full Text PDFRecent developments of burst-mode lasers and imaging systems have opened new realms of simultaneous diagnostics for velocity and density fields at a rate of 1 kHz-1 MHz. These enable the exploration of previously unimaginable shock-driven turbulent flow fields that are of significant importance to problems in high-energy density physics. The current work presents novel measurements using simultaneous measurements of velocity and scalar fields at 60 kHz to investigate Richtmyer-Meshkov instability (RMI) in a spatio-temporal approach.
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