The effect of outer cylinder rotation on Taylor-Couette flow at small aspect ratio

We present the results of a combined experimental and numerical study of Taylor-Couette flow where both inner and outer cylinders rotate. Excellent quantitative agreement has been obtained between finite-element calculations and experimental measurements for a range of aspect ratios and rotation rates. Counter-rotation was found to enhance the breaking of the reflectional symmetry about the midplane of the apparatus, corotation to suppress symmetry breaking. For the region of parameter space explored, increasing the corotation of the outer cylinder had a qualitatively similar effect to increasing the aspect ratio, and vice versa. (C) 2003 American Institute of Physics.