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A Protocol for Real-time 3D Single Particle Tracking
Published on: January 3, 2018
Phase-doppler interferometry with probe-to-droplet size ratios less than unity. I. Trajectory errors.
P A Strakey1, D G Talley, S V Sankar
1US Air Force Research Laboratory, AFRLyPRSA, 10 East Saturn Boulevard, Edwards Air Force Base, California 93524, USA. peter_strakey@ple.af.mil
Applied Optics
|March 20, 2008
Summary
Phase-Doppler interferometry effectively measures droplet size and velocity by minimizing trajectory errors. This technique uses a validation scheme and scattered light intensity for accurate probe volume characterization and mass flux measurements.
Area of Science:
- Fluid Dynamics
- Optical Measurement Techniques
- Particle Characterization
Background:
- Phase-Doppler interferometry (PDI) is a common technique for measuring droplet size and velocity.
- Trajectory-dependent scattering errors can affect the accuracy of PDI measurements.
- Accurate characterization of the probe volume is crucial for reliable results.
Purpose of the Study:
- To develop and validate a method for eliminating trajectory-dependent scattering errors in PDI.
- To quantitatively assess trajectory errors using optical models.
- To establish a robust method for determining probe volume cross-sectional area for mass flux measurements.
Main Methods:
- Coupling PDI with a phase-ratio and intensity-validation scheme.
- Utilizing ray-tracing and geometric-optics models for error analysis.
- Performing stochastic trajectory calculations to demonstrate error types and magnitudes.
- Conducting measurements with monodispersed water droplet streams and glass beads.
Main Results:
- The phase-ratio and intensity-validation scheme effectively eliminates trajectory-dependent scattering errors.
- Model calculations accurately predicted trajectory errors.
- Scattered-light intensity provides a robust method for determining probe cross-sectional area.
- Measurements validated the model calculations and characterized the probe volume.
Conclusions:
- The validated PDI technique with the proposed scheme offers accurate droplet size and velocity measurements.
- The method enhances the reliability of PDI by mitigating trajectory errors.
- Accurate probe volume determination using scattered-light intensity is critical for precise mass flux calculations.
