Temperature Measurements and Surface Visualization in Microchannel Flows Using Infrared Thermography

Significant developments in detailed quantitative microscale fluid flow visualization have been made in recent years. However, spatially resolved surface temperature measurements in microchannels have received far less attention. This paper introduces quantitative and qualitative surface temperature measurement in microscale flows using infrared (IR) thermography. This technique is applicable for channel dimensions of up to 10 μm. In order to determine temperatures accurately, careful attention toward proper choice of windows, elimination of specular reflections from channel walls, and estimation of local emissivity changes is warranted. These concerns are addressed in the paper, and preliminary results of detailed temperature distribution in a single-phase mini-channel flow are presented.