An LDA probe with optimized measuring volume was obtained based on repeated adjustments of a preconfigured LDA system with a calibrated spinning disc. A retriggerable pulse-width-and-time-delay module was used to trigger and freeze favorable Doppler bursts. After a repeated beam-steering procedure and a fringe-pattern analysis, we found that the variation of fringe spacing throughout the measuring volume was reduced from 3% to 0.28%, such that the adjusted probe gave more accurate measurements. To verify this applicability in velocity calibration, the fringe spacing of the adjusted LDA measuring volume was treated as a velocity coefficient, and its mean and measurement uncertainty was experimentally estimated. Analysis shows that the expanded uncertainty of the coefficient was 0.10% at the 95% level of confidence for both the components of the LDA. The results demonstrated that the adjusted LDA system was qualified to perform accurate flow measurement.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Mechanical Engineering
- Electrical and Electronic Engineering