Laminar flow of a shear-thickening fluid in a 90° pipe bend

The non-Newtonian fluid flow in a sharp 90 degrees curved pipe is studied numerically to obtain the pressure loss coefficient prompted by disagreement between the existing empirical correlations and results obtained by computer codes. This disagreement results from presumption of fully developed flow throughout the curvature (correlations) while the actual flow is partially developed for the Newtonian and sharp 90 degrees curved bend non-Newtonian flows, and fully developed for slightly bent 90 degrees curvature non-Newtonian flow. The Quadratic model is employed to accommodate the shear-thickening behavior of an electrostatic ash and water mixture. Numerical results are obtained for different values of Reynolds number. Finally, results for local pressure loss coefficient are compared with values obtained for the Power law rheological model. (C) 2006 The Japan Society of Fluid Mechanics and Elsevier B.V. All rights reserved.