Power-Law Fluid Flow Passing Two Square Cylinders in Tandem Arrangement

Abstract

Two-dimensional laminar flow of a power-law fluid passing two square cylinders in a tandem arrangement is numerically investigated in the ranges of 1< Re< 200 and 1 ≤ G ≤ 9. The fluid viscosity power-law index lies in the range 0.5 ≤ n ≤ 1.8, which covers shear-thinning, Newtonian and shear-thickening fluids. A finite volume code based on the SIMPLEC algorithm with nonstaggered grid is used. In order to discretize the convective and diffusive terms, the third order QUICK and the second-order central difference scheme are used, respectively. The influence of the power-law index, Reynolds number and gap ratio on the drag coefficient, Strouhal number and streamlines are investigated, and the results are compared with other studies in the literature to validate the methodology. The effect of the time integration scheme on accuracy and computational time is also analyzed. In the ranges of Reynolds number and power-law index studied here, vortex shedding is known to occur for square cylinders in tandem. This study represents the first systematic investigation of this phenomenon for non-Newtonian fluids in the open literature. In comparison to Newtonian fluids, it is found that the onset of leading edge separation occurs at lower Reynolds number for shear-thinning fluids and is delayed to larger values for shear-thickening fluids.

Unconfined Unsteady Laminar Flow of a Power-Law Fluid across a Square Cylinder

“…In the same figure results from Franke et al [13], Sen et al [14], Ehsan et al [15], and Zhao [16] Figure 5C it is seen that the large computational domain allows some minor frequencies (superharmonics) to appear, whereas these minor frequencies disappear in the narrow computational domain. After the above comparisons results for the nonNewtonian fluids are presented.…”

“…In the same figure results from Franke et al [13], Sen et al [14], Ehsan et al [15], and Zhao [16] are included for comparison. In the same figure results from the present work are included for the cases H/D = 50,000 and H/D = 20.…”

The Efficiency of Clinical Laboratories: The case of Iran

“…Today, according to new diagnostic methods, laboratories are one of the most important parts of the health system and account for approximately 1.7% of the total hospital costs. Laboratories are a very sensitive and important work environment due to the variety of work and the variety of specialists in different elds, so they need more attention and evaluation (1,2).…”