Effect of wall alignment in a very short rotating annulus

This paper reports numerical results of the study of effects of cylinders wall alignment in a small aspect ratio Taylor–Couette system. The investigation concerns bifurcations of steady vortical structures when the cylindrical walls defining the gap are not perfectly parallel. The imperfection is introduced by opening the outer fixed cylinder with a certain angle with regard to the vertical to form a tapered very short liquid column and keeping the inner rotating cylinder wall vertical. The numerical results obtained for the velocity components have revealed that bifurcation from a particular mode to another one occurs at a range of specific values of the inclination angle of the outer cylinder. The band width of the angle at which bifurcation occurred depended on the Reynolds number Re and was found to become narrower as Re increased. It is shown that geometrically broken symmetry can yield flow symmetry for specific combinations of geometrical and dynamical parameters.