A study on time-periodic finite-gap Taylor-Couette flows

We investigate the flow between two concentric cylinders whose angular velo cities are periodic in time. We derive an approximate expression of the bas e flow which includes the finite gap between the cylinders. We measure the time dependence in a period of the axial velocity for co-rotating cylinders by ultrasound Doppler velocimetry. Fire then consider the quasi-static lin ear stability analysis of this flow for low and intermediate frequencies. T he quasi-static finite-gap results are in close agreement with experimental data. (C) Academie des Sciences/Elsevier, Paris.