Development of Doppler Global Velocimeter (DGV)
Abstract
A two component Doppler Global Velocimeter (DGV) and a two component Point Doppler Velocimeter (PDV) are described. Velocity measurements for both systems to quantify accuracy are presented. Results are presented for velocity distribution over the surface of a rotating wheel and fully developed turbulent pipe flow. Accuracy of PDV wheel velocity data is +1% of full scale, while linearity of a single channel is on the order of +0.5%. Overall accuracy of wheel data matches cell calibration repeatability. PD pipe flow data show consistent turbulence intensities, and mean velocities agree with pitot probe data. However, a mean velocity offset error is observed. DGV system accuracy has also been investigated; this system uses four 8 bit Hitachi CCD cameras, and a Matrox Genesis frame grabber board for image acquisition. For rotating wheel results, RMS noise levels are on the order of +/- 1 m/sec, while total velocity range errors are between +/- 1-2 m/sec. RMS noise is dominated by camera resolution. Pipe flow mean velocity measurements show reasonable agreement with centerline pitot probe data. The observed zero velocity offset has been corrected through use of a reference tab, to record zero velocity signals.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1998
- Accession Number
- ADA346449
Entities
People
- John Kuhlman
Organizations
- West Virginia University