THEORETICAL AND EXPERIMENTAL-STUDY OF DEVELOPMENT OF 2-DIMENSIONAL STEADY AND UNSTEADY WAKES WITHIN CURVED CHANNELS

Development of steady and periodic unsteady wake flows downstream of s tationary and rotating cylindrical rods within a curved channel under zero longitudinal pressure gradient is theoretically and experimentall y investigated. Wake quantities such as the mean velocity and turbulen t fluctuations in longitudinal and lateral directions, as well as the turbulent shear stress, are measured. For the nondimensionalized veloc ity defect, affine profiles are observed throughout the pow regime. Ba sed on these observations and using the transformed equations of motio n and continuity, a theoretical frame work is established that general ly describes the two-dimensional curvilinear wake flow. To confirm the theory, development of steady and periodic unsteady wakes in the abov e curved channel are experimentally investigated. The detailed compari son between the measurement and the theory indicates that the complex steady and unsteady wake flows are very well predicted.