LAMINAR-FLOW AND HEAT-TRANSFER TO PSEUDOPLASTIC FLUIDS IN PIPES

Experimental investigation of heat transfer to pseudoplastic fluids under constant heat flux condition was carried out. Experimental data for thermally developing heat transfer to the laminar flow of highly viscous fluids (K from 1.6-13.7 Pa s(n)) in 0.0 1 6 and 0.021 m diameter pipes were collected. The experimental local heat transfer coefficients are also compared with the predictions of a computer code based on the equations of continuity, momentum and energy. The theoretical model incorporates effects such as variable viscosity, natural convection and viscous dissipation. The numerical predictions fit the experimental data excellently. Results show that the difference of the radial temperature is very large in heat transfer to highly viscous fluids.