High-resolution LDA measurements of Reynolds stress in boundary layers and wakesThe turbulent character of the boundary layer and wake associated with an airfoil has been studied at a Reynolds number of 1,000,000 and a Mach number of 0.1. To accomplish these measurements, a unique laser Doppler anemometer (LDA) has been developed that is capable of sensing two velocity components from a remote distance of 2.13 m. Using special simultaneity logic and counter-type signal processors, the geometrical features of the LDA have been exploited to provide variable spatial resolution as low as 0.2 mm. By combining the LDA with an on-line computerized data acquisition and display system, it has been possible to measure mean velocity and Reynolds stress tensor distribution at several locations along the upper surface of a 0.9-m-chord, flapped airfoil installed in the Ames 7- by 10-Foot Wind Tunnel.
Document ID
19800042797
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Orloff, K. L. (NASA Ames Research Center Moffett Field, CA, United States)
Olson, L. E. (NASA Ames Research Center Moffett Field, Calif., United States)