Particle & Particle Systems Characterization, Vol.25, No.2, 168-175, 2008
Particle size classification of glass particles using aerodynamic jet vectoring
An experimental demonstration of a new, non-contact particle characterization technique called Aerodynamic Vectoring Particle Sorting (AVPS) is presented. AVPS uses secondary blowing and suction control flows-flows that are a fraction of the jet flow rate-to sharply change the direction of a planar, particle-laden jet. As the jet is vectored, particles present in the flow experience a resultant drag force, dependent upon their size, that balances inertia. Since this balance determines the particle's trajectory, vectoring the flow leads to a separation of particles downstream. This simple, low-pressure-drop sorting technique classifies particles with less risk of damage or contamination than currently available sorting devices. Particles from 10-40 mu m and 2.5 times the density of water have been sorted to an accuracy of 1.5 mu m. Sorting of heavy particles such as these is accomplished at very low speeds, reducing the tendency of damage to the particles. Lighter particles are sorted at higher speeds. Particles from 5-40 mu m and 0.6 times the density of water were sorted to an accuracy of 6.6 mu m. AVPS is also shown to be capable of concentrating aerosols. Our measurements indicate that an air sample containing water-like particles can be concentrated by a factor of 10 using AVPS.