Convective laminar flow of food additives solutions in circular entrance region

This is an investigation of non isothermal and non-Newtonian laminar flow in the entrance region of short tubes. The flow is steady, incompressible and tube wall has constant temperature with heating and cooling. Experimental work was conducted using water solutions of Xanthan and Guar gums which exhibited pseudoplastic behavior. Experiments lie in the ranges: 2×10−04 < Gz−1 < 10−02, 300 < Pr < 1000, 30 < Re < 400 and 30.9 < L/D < 135.8. Results were reported as non-dimensional correlations allows practical calculations of Nusselt, Graetz and Stanton. The Stanton number was modified in this work for the potency of Reynolds and one demonstrated a good correlation to distinguish the heating and cooling conditions. The results for the Nusselt number are compatible with the literature.