End effects in low aspect ratio Taylor–Couette flow

Abstract

Taylor–Couette flow with a low aspect ratio cylinder suffers from end effects due to the finite-span of the gap between the cylinder sides and the secondary flow in the region below the inner cylinder. We experimentally explore these end effects by varying the cylinder aspect ratio between 6.67 and 40 for a range of wall gap widths and bottom gap heights. For these geometries, end effects (i.e. non-ideal Taylor–Couette flow) can be substantial due to both features of the finite-span and the bottom secondary flow. In some cases, the finite-span effects extended between 20% and 30% of the way into the Taylor–Couette flow region, and the secondary flow at the bottom accounted for nearly half of the total measured torque. By taking these effects into consideration, our high aspect ratio results agreed well with those obtained by Taylor (Taylor 1936 Proc. R. Soc. Lond. A 157 , 546–564. (doi: 10.1098/rspa.1936.0215 )) at considerably higher aspect ratios. This article is part of the theme issue ‘Taylor–Couette and related flows on the centennial of Taylor’s seminal Philosophical Transactions paper (part 1)’.

Taylor–Couette and related flows on the centennial of Taylor’s seminalPhilosophical Transactionspaper: part 2

“…Part 1 of this two-part theme issue explored contemporary topics related to Taylor-Couette flow including turbulent, convective and two-phase flows as well as extensions to magnetohydrodynamic, ferrofluidic and viscoelastic flows and flow geometries that are closely related to the Taylor-Couette problem [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Part 2 of this theme issue continues with review articles and research articles having their origin in Taylor's 1923 paper.…”