An Experimental Study of Heat-Transport Characteristics of Oscillatory Flow in a Minichannel

The axial-heat-transport characteristics of oscillatory flow of water in mini-tubes were investigated to provide possible next-generation electronics cooling in thermal management devices. The mini-tubes were made of SUS304 with inner diameters of 0.3, 0.5, and 0.8 mm, which were smaller than those of reported in the literature. The oscillation frequency of the liquid column ranged from 0.38 to 12.5 Hz and its tidal displacement ranged from 25 to 100 mm. The effective thermal diffusivity was defined to evaluate heat transport rate for each experimental conditions and to compare with existing analytical-model results. The measured effective thermal diffusivities divided by the square of tidal displacement and angular frequency drew “tuning-curves” in the graph, which are similar to the curve drawn by the analytical-model. Regarding the magnitudes of the diffusivities, although the agreement between the measured diffusivities and calculated diffusivities are fairly good, the measured values are roughly twice higher than the prediction results at the frequencies of about 3 Hz and the lower.