Real-time observation of the change in light scattering from droplets with increasing deformity

Commercial aerodynamic particle sizing instruments generally achieve the desired particle size measurement by accelerating a sample airstream in which the particles are suspended and measuring the velocity acquired by individual particles. The accelerating flow regime can cause liquid droplets to deform and this subsequently introduces errors. In this paper, we present an apparatus that enables droplet deformation to be observed by recording the spatial light scatter intensity. The paper presents experimental data in video format showing the changes that occur in the light scattering from droplets as a function of increasing flow rate/deformation.