Statistical bias in LDA measurements
Abstract
Mean velocity measurements with LDA in a turbulent flame have indicated a statistical bias in this flow involving strong density gradients.Derivation of seeded flow equations explains the difference between the various expressions commonly used to statistically average LDA data. The actual velocity can always be obtained using both the time-between-counts data and the instantaneous velocity data. With some restrictions constant and homogeneous injection rate of seeding particles, only one count per Doppler burst, constant scattering efficiency of each particle - the information available on LDA counters can give the Favre average velocity and the gas density.
- Publication:
-
Dantec Information (ISSN 0900-5579
- Pub Date:
- February 1987
- Bibcode:
- 1987dant.rept....7D
- Keywords:
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- Bias;
- Laser Anemometers;
- Laser Doppler Velocimeters;
- Velocity Measurement;
- Flame Propagation;
- Gas Density;
- Statistics;
- Temperature Gradients;
- Turbulent Flow;
- Instrumentation and Photography