Published online by Cambridge University Press: 20 April 2006
The properties of steady cellular flows between a rotating cylinder and a stationary outer one of square cross-section have been investigated experimentally. Results for the primary-flow selection process, which involves four-cell and six-cell states, are intricate but bear a reassuring qualitative resemblance to those obtained previously for the standard Taylor–Couette model. In addition, the existence of anomalous modes disconnected from the primary flow has been demonstrated and their dependence upon the length of the flow domain studied. The phenomena are found to be in accord with the abstract theoretical framework that has been successfully used to interpret previous experimental observations on steady-flow problems with multiple solutions.