2010 · 13 citations · 8 references
EngineeringMechanical EngineeringHeat TransferThermal AnalysisTransport PhenomenaCooling SystemsEvaporative CoolingHeat ConductionHeat FlowHeat Transfer In FluidsHeat Transfer ModelingAnnular Flow RegimesDryout OnsetDryout PhenomenaHeat Transfer CoefficientsHeat Transfer In Annular FlowHeat Transfer In ChannelsMass FluxTwo-phase Flow Regimes
Heat transfer to an evaporating refrigerant and/or dielectric liquid in a microgap channel can provide very high heat transfer coefficients and volumetric cooling rates. Recent studies at Maryland have established the dominance of the annular flow regime in such microgap channels and related the observed high-quality peak of an M-shaped heat transfer coefficient curve to the onset of local dryout. The present study utilizes infrared thermography to locate such nascent dryout regions and operating conditions. Data obtained with a 210 micron microgap channel, operated with a mass flux of 195.2 kg/m2-s and heat fluxes of 10.3 to 26 W/cm2 are presented and discussed.
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