Experimental investigation on convective heat transfer of non-Newtonian flows of Xanthan gum solutions in microtubes

Convective heat transfer of thermally developing flows of non-Newtonian Xanthan gum solutions, a potential candidate for cooling and heating applications, was experimentally investigated in a microtube. Xanthan gum solutions of different concentrations (0.1, 0.5, 1 and 4 g/L), whose properties matched with the Carreau-Yasuda model, were tested at different fixed flow rates at constant uniform heat flux. The results revealed that the heat flux was effective at more downstream locations, and the enhancements were attained at low concentrations (c = 0.1 g/L) and low flow rates. Therefore, at the same flow rate, Xanthan gum solutions are not very good candidates for enhancement of convective heat transfer unless they are used at both low concentrations and low flow rates.