| A newly designed particle separator, named the Aerodynamic Module (ADM) has been investigated. Its operation is such that most of the gas leaves through annular gaps while the dust, by virtue of inertia, remains inside and is concentrated in a small fraction of the original which flows to a hopper.; The Magnus force and Saffman force were considered but are too small to be significant factors in collecting fine particles. Inertia and aerodynamic drag are the main factors.; The ADM was tested with corn starch and coal ash from a baghouse hopper after a multicyclone. The particle size distribution was measured at inlet and outlet, and total and fractional collection efficiencies were obtained. FLUENT code computations were done assuming spherical particles with specific gravity of 2.0. Static pressure was measured at the inlet and outlet, and this pressure drop agreed with the predicted one, which justifies the appropriateness of the turbulence modeling. Particle loadings up to 6 gr/ft{dollar}sp3{dollar} in air at standard conditions and up 3 min duration time were used. Total particle collection efficiencies of 90% for corn starch and 70% for coal fly ash were measured at inlet velocities of 80 ft/s (2700 cfm) and 6 in. water pressure drop.; The cascade impactor measurements showed 50% collection efficiency for 1 to 3 micron particles. However the CFD computations showed a cut size (50% collection) of 5.5 micron for 2550 cfm and for 4000 cfm the cut size decreased to 4.2 micron. Collection efficiency increased with increasing size to near 100% up to 20 micron, and then decreased due to bounce of large particles at the vanes with smaller diameter. Different hopper pressure setting, different gap between the vanes and three other types of vane geometries were simulated. The performance of the prototype design gave the best collection efficiency. |
