ILA Phase Doppler Anemometry Systems

The ILA R&D PDA System is easy to use and can simultaneously measure the velocity and the side of particles in fluid dynamics applications. No laser is included in the PDA Receiving Optic itself. An additoinal LDV probe is therefore required for operation. Since particle size determination does not require a calibration factor, the accuracy is maintained and the LDV Probe does not need to be recalibrated.

Features:

• Simultaneous measurement of velocity and particle size
• Photo-detectors integrated in receiving optic
• Simple setup and alignment
• High measuring accuracy
• High long term stability
• Manual positioning system for angle/laser beam alignment (optional)
• Automatic traversing (optional)
• Robust transport suitacase (optional)

The PDA Receiving Optic and the LDV Probe are arranged at a fixed angle to each oterh (see example measuring setup in Fig 2), on which the phase to diameter factors for the particle size determination depend. This has a direct impact on the measurement accuracy. The lgiht scattered by the particles inside the measuring valume is collected forwards, under the fixed angle, by the receiving lens of the PDA Receiving Optic. For the calculation of the particle sizes, a factor must be known. This factory depends on the focal lens of the tranmistting and receiving optics, the laser frequency, the angle of intersection of the laser beams and the refractive index of the particles.