ContributionsFollow the blue link(s) below for abstracts and full text pdfs .
Author index ►Samer Alokaily, Kathleen Feigl, Franz X. Tanner, Erich J. Windhab
Most cited recent articles ►
Articles for free download ►
Search conferences ►
Numerical Simulations of the Transport of Newtonian and Non-Newtonian Fluids via Peristaltic Motion
Appl. Rheol. 28:3 (2018) 32832 (15 pages) ►
Two geometrical models are developed to simulate fluid transport via peristaltic motion in tubes of uniform or linearly decreasing radius: A 2-D axisymmetric tubular model and a 2-D axisymmetric conical model. In both models, peristaltic motion is induced by a traveling wave along the wall of the computational domain which deforms the wall and the computational mesh. These geometrical models are coupled with a finite volume solver from the open source software package OpenFOAM which is used to simulate the peristaltic flow for different Newtonian and non-Newtonian fluids in the laboratory (or Eulerian) frame of reference. After validation of the solver with experimental data, simulations are performed in each geometrical model to determine the influence of a given set of parameters on peristaltic flow behavior and transport efficiency. The parameters that are varied include the wave speed, relative occlusion, Newtonian viscosity, and power-law index for shear-thinning non- Newtonian fluids. For both computational models, the transport efficiency is found to increase strongly with relative occlusion, to decrease as the amount of shear-thinning increases, and to be independent of wave speed. In the tubular model, transport efficiency is found to be independent of Newtonian viscosity, while in the conical model, it decreases as viscosity decreases for Reynolds numbers greater than one.► Cite this publication as follows:
Alokaily S, Feigl K, Tanner FX, Windhab EJ: Numerical Simulations of the Transport of Newtonian and Non-Newtonian Fluids via Peristaltic Motion, Appl. Rheol. 28 (2018) 32832.
Franz X. Tanner, Abdallah A. Al-Habahbeh, Kathleen A. Feigl, Samsun Nahar, Shaik A. K. Jeelani, William R. Case, Erich J. Windhab
Numerical and Experimental Investigation of a Non-Newtonian Flow in a Collapsed Elastic Tube
Appl. Rheol. 22:6 (2012) 63910 (8 pages) ►
Simulations are performed to investigate the flow of a shear-thinning, non-Newtonian fluid in a collapsed elastic tube and comparisons are made with experimental data. The fluid is modeled by means of the Bird- Carreau viscosity law. The computational domain of the deformed tube is constructed from data obtained via computer tomography imaging. Comparison of the computed velocity fields with the ultrasound Doppler velocity profile measurements show good agreement, as does the adjusted pressure drop along the tube.s axis. Analysis of the shear rates show that the shear-thinning effect of the fluid becomes relevant in the crosssections with the biggest deformation. In fact, the maximum shear rate is about a factor of thirty larger than its corresponding maximum value in the undeformed tube, and the viscosity is reduced by a factor of two. The effect of the shear-thinning behavior has also been compared with identical simulations carried out for a Newtonian fluid.► Cite this publication as follows:
Tanner FX, Al-Habahbeh AA, Feigl KA, Nahar S, Jeelani SJA, Case WR, Windhab EJ: Numerical and Experimental Investigation of a Non-Newtonian Flow in a Collapsed Elastic Tube, Appl. Rheol. 22 (2012) 63910.
K.A. Feigl, H.-C. Öttinger
Investigation of Die Entry Flows of Polymer Melts
Appl. Rheol. 6:2 (1996) 59 ►
► Cite this publication as follows:
Feigl KA, Ottinger HC: Investigation of Die Entry Flows of Polymer Melts, Appl. Rheol. 6 (1996) 59.
© Applied Rheology 2019