Abstract
The flow between two concentric cylinders with the inner one rotating and with an imposed pressure-driven axial flow is studied experimentally. The objective of this work is to study the detailed flow field including the vortical structure. In the first, the performance of the experimental equipments was studied by comparing the mean velocity profiles with the theoretical ones. The helical vortex at high Reynolds number locates almost around the inner cylinder but not near the outer cylinder. This vortex pattern is different from that of low Reynolds number reported by Lueptow et al.
