Performance of laser Doppler velocimeter with polydisperse seed particles in high speed flows
Abstract
The flowfield behind an oblique shock wave, where the LDV measured velocities are seed particle size dependent, was used to investigate the effects of LDV system parameters on the range of detectable polydisperse seed particles. The parameters included frequency shifting, laser power, scattered signal amplification level, and number of required fringe crossings. The results showed that with polydisperse seed particles ranging from 0.1 to 4.0 microns available in the flow, the average diameter of the detected particles could change from 0.2 to 3.0 microns by changing different LDV system parameters. The effects of this shift in the range of detectable particles on the frequency response of LDV was discussed.
- Publication:
-
26th AIAA Aerospace Sciences Meeting
- Pub Date:
- January 1988
- Bibcode:
- 1988aiaa.meetX....S
- Keywords:
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- Flow Distribution;
- Laser Doppler Velocimeters;
- Particle Size Distribution;
- Seeds;
- Shock Waves;
- Two Phase Flow;
- Differential Equations;
- Nonlinear Equations;
- Photometers;
- Signal To Noise Ratios;
- Instrumentation and Photography