Experimental characterization of Digitized Heat Transfer in circular microchannels

Digitized Heat Transfer (DHT) is a relatively new and promising form of thermal management that uses discrete droplets to remove excess heat. In this investigation, DHT is studied using infrared thermography to measure the heat transfer to a digitized flow in a microchannel that is subject to a constant heat flux. Results show that heat transfer, characterized by Nusselt number (Nu), exhibits an initial power law decay followed by periodic oscillations whose period is dependent on droplet aspect ratio. The overall magnitude of Nu is found to have a positive correlation with Reynolds number (Re). Using two scaling constants given by equation and equation, the experimental Nu curves for various flows are scaled and approximately collapsed to a single curve. In the future, these simplified Nu curves will be helpful in analyzing and designing potential DHT thermal solutions.