Title :
A long-range laser velocimeter
Author :
Reinath, Michael S.
Author_Institution :
NASA Ames Res. Center, Moffett Field, CA, USA
fDate :
1/1/1991 12:00:00 AM
Abstract :
A long-range laser velocimeter (LV) developed for remote operation from within the flow fields of large wind tunnels is described. Emphasis is placed on improvements in optical hardware as well as additions to data acquisition and processing techniques. The method used for data reduction of photon resolved signals is outlined in detail, and measurement accuracy is discussed. To study the performance of the LV and verify the measurement accuracy, laboratory measurements were made in the flow field of a 10-cm-diameter, 30-m/s axisymmetric jet. The measured velocity and turbulence intensity surveys are compared with measurements made with a hot-wire anemometer. Additionally, the LV was used during the flow calibration of the 80-ft×120-ft wind tunnel to measure the test-section boundary layer thickness at the maximum wind tunnel speed of 51.5 m/s. The requirements and techniques used to seed the flow are discussed, and boundary-layer surveys of mean velocity and turbulence intensity of the streamwise component and the component normal to the surface are presented. The streamwise component of mean velocity is compared with data obtained with a total pressure rake
Keywords :
boundary layer turbulence; computerised instrumentation; data acquisition; data reduction; flow visualisation; laser velocimeters; telemetering; wind tunnels; 10 cm; 120 feet; 80 feet; NASA; artificial seeding; axisymmetric jet; boundary layer thickness; data acquisition; data reduction; flow calibration; flow fields; laboratory measurements; long-range laser velocimeter; mean velocity; photon resolved signals; remote measurement; streamwise component; total pressure rake; turbulence intensity; wind tunnels; Calibration; Data acquisition; Fluid flow measurement; Hardware; Laboratories; Signal resolution; Testing; Thickness measurement; Velocity measurement; Wind speed;
Journal_Title :
Aerospace and Electronic Systems, IEEE Transactions on
