Accounting for Laser Extinction, Signal Attenuation, and Secondary Emission While Performing Optical Patternation in a Single Plane

摘要

An optical patternation method is described where the effects of laser extinction and signal attenuation can be corrected for, and where secondary scattering effects are reduced by probing the spray with a swept beam instead of a laser sheet. The use of the swept beam also allows the signals to be detected within the same plane as the sweep, thus eliminating the requirement to perform a tedious 3D mapping in order to correct for signal attenuation effects. Conditions are described in which the method might possibly be applied to non-spherical droplets. Measurements in a fan spray indicate that the method is consistent with PDI measurements.