FRICTION AND HEAT AND MASS-TRANSFER FOR TURBULENT PSEUDOPLASTIC NON-NEWTONIAN FLUID-FLOWS IN ROUGH PIPES

Friction factor and heat and mass transfer coefficient correlations ar e developed for turbulent pseudoplastic (purely viscous or inelastic) non-Newtonian fluids flowing through rough pipes. A correlation for fr iction factor which is applicable in the region of transition from the smooth to the fully-rough regime is proposed. It is obtained by addin g the two correlations for the limiting situations, i.e. smooth pipes and fully-rough pipes. The predictions of the proposed correlation are compared with published experimental data and other previous correlat ions. A model for heat and mass transfer is developed on the basis of the Levich three-zone model. It is found that the proposed model is ca pable of predicting satisfactorily heat and mass transfer coefficients for Newtonian and pseudoplastic non-Newtonian fluid flow in rough pip es.