BEGIN:VCALENDAR VERSION:2.0 PRODID:-//wp-events-plugin.com//6.6.4.4//EN TZID:Asia/Jerusalem X-WR-TIMEZONE:Asia/Jerusalem BEGIN:VEVENT UID:0-1539@aerospace.technion.ac.il DTSTART;TZID=Asia/Jerusalem:20260311T133000 DTEND;TZID=Asia/Jerusalem:20260311T143000 DTSTAMP:20260308T125523Z URL:https://aerospace.technion.ac.il/events/seminar-slot-2026-03-11/ SUMMARY:Spatially resolved heat transfer coefficients in water-sheet spray cooling at sub-saturation wall temperatures using infrared thermography DESCRIPTION:Lecturer:Charles Touitou\n Faculty:The Stephen B. Klein Faculty of Aerospace Engineering at the Technion \n Institute:Technion – Israel Institute of Technology\n Location:The seminar will be held online only v ia Zoom\n Zoom: https://technion.zoom.us/j/94050711666\n Abstract: \n\n\nS pray cooling is a high-performance thermal-management approach used when c onventional single-phase convection becomes limited by available area or m ass flow. However\, obtaining spatially resolved measurements of local hea t transfer coefficients remains challenging.\nThis work presents an experi mental method for quantifying spatially resolved local heat transfer coeff icients during water-sheet spray cooling at sub-saturation wall temperatur es. The approach combines uniform Joule heating of a 25 μm thick metallic foil with infrared thermography in a multilayer glass-adhesive-foil assem bly. A conduction-based reconstruction procedure accounting for through-th ickness thermal resistance\, lateral heat spreading\, backside convection\ , and radiation losses is used to determine the wetted-surface temperature and local convective heat flux\, enabling direct mapping of the heat tran sfer coefficient over the full spray footprint.\nThe measurement technique is first validated using a fully developed single round air jet over a wi de range of Reynolds numbers from 9\,000 to 60\,000\, and multiple imposed heat flux levels (0.76 – 2.5 kW/cm2). Measurements obtained with Consta ntan and Inconel 600 heater foils yield nearly identical Nusselt number di stributions and axisymmetric stagnation-region peaks\, demonstrating insen sitivity to heater material and heat-flux level.\nThe validated method is then applied to cooling produced by a convergent microfluidic nozzle gener ating a planar water sheet that atomizes prior to impact. The measurements are still independent on the heat flux level (7 – 54 kW/cm2) and reveal strongly non-uniform heat transfer footprints governed by water sheet spr eading and breakup dynamics. By restricting operation to sub-saturation wa ll temperatures\, the experiments isolate single-phase convective transpor t and provide benchmark datasets for spray-cooling models in the absence o f boiling.\nThe proposed technique provides a robust framework for high-re solution characterization of spray cooling performance and is broadly appl icable to thermal management systems and microfluidic cooling architecture s.Charles Touitou has been an MSc student in the Faculty of Aerospace Engi neering since 2024 and currently works as an aerodynamics engineer at Elbi t Systems.\n\nSpecial Notice: Following a situational assessment held by t he Technion Management\, and in accordance with Home Front Command guideli nes\, the following Aerospace Engineering seminar will be held online only via Zoom.\n\n \;\n\n \;\n\n\n\n Details: \n CATEGORIES:Seminars,סמינרים LOCATION:The seminar will be held online only via Zoom END:VEVENT BEGIN:VTIMEZONE TZID:Asia/Jerusalem X-LIC-LOCATION:Asia/Jerusalem BEGIN:STANDARD DTSTART:20251026T010000 TZOFFSETFROM:+0300 TZOFFSETTO:+0200 TZNAME:IST END:STANDARD END:VTIMEZONE END:VCALENDAR