On the physics of viscoplastic fluid flow in non-circular tubes |
| |
Institution: | 1. Department of Mathematics, Gaziantep University, Gaziantep, Turkey;2. Departments of Applied Mathematics and Mechanical Engineering, Botswana International University of Science and Technology, Palapye, Botswana\n;3. CICES, Universidad de Santiago de Chile, Santiago, Chile;1. Laboratoire Physique et Chimie Théoriques (LPCT, UMR CNRS UL 7019), Institut Jean Barriol, Université de Lorraine, Rue Victor Demange, 57500 Saint-Avold, France;2. Laboratoire d''Acoustique de l''Université du Mans - UMR CNRS 6613 Avenue Olivier Messiaen 72085 Le Mans cedex 09, France |
| |
Abstract: | Flow of Bingham plastics through straight, long tubes is studied by means of a versatile analytical method that allows extending the study to a large range of tube geometries. The equation of motion is solved for general non-circular cross-sections obtained via a continuous and one-to-one mapping called the shape factor method. In particular the velocity field and associated plug and stagnant zones in tubes with equilateral triangular and square cross-section are explored. Shear stress normal to equal velocity lines, energy dissipation distribution and rate of flow are determined. Shear-thinning and shear-thickening effects on the flow, which cannot be accounted for with the Bingham model, are investigated using the Hershey-Bulkley constitutive formulation an extension of the Bingham model. The existence and the extent of undeformed regions in the flow field in a tube with equilateral triangular cross-section are predicted in the presence of shear-thinning and shear-thickening as a specific example. The mathematical flexibility of the analytical method allows the formulation of general results related to viscoplastic fluid flow with implications related to the design and optimization of physical systems for viscoplastic material transport and processing. |
| |
Keywords: | Viscoplastic Bingham Hershey-Bulkley Non-circular tube Plug and stagnant zones |
本文献已被 ScienceDirect 等数据库收录! |
|