Abstract: Disclosed are multiple stage rotating coalescer devices comprising a first stage and a second stage. The first stage may include a rotating coalescing element comprising coalescing media. The second stage is positioned either upstream or downstream or the first stage. The second stage may include one of: (i) a rotating cone stack separator, or (ii) a separate rotating coalescing element comprising coalescing media.

Abstract: Disclosed are multiple stage rotating coalescer devices comprising a first stage and a second stage. The first stage may include a rotating coalescing element comprising coalescing media. The second stage is positioned either upstream or downstream or the first stage. The second stage may include one of: (i) a rotating cone stack separator, or (ii) a separate rotating coalescing element comprising coalescing media.

Abstract: A filter is provided by pleated filter media having a plurality of pleats defined by wall segments extending axially along an axial direction along an axis and extending transversely along a transverse direction between first and second sets of pleat tips at first and second sets of axially extending bend lines. The pleated filter media spans laterally along a lateral span along a lateral direction, with the wall segments being spaced from each other by lateral gaps. The pleats have a pleat depth along the transverse direction along the wall segments between the first and second sets of pleat tips. The pleat depth varies as the pleated filter media spans laterally along the lateral direction.

Abstract: A filter assembly has a plurality of filter elements extending longitudinally in a housing interior volume and shaped to increase filter media area by reducing unused space in the interior volume as compared to filter elements having a cylindrical shape.

Abstract: A filter has multiple pleated filter elements having axially extending channels having a transverse pleat channel height and a lateral channel width. The pleated filter elements have different channel heights.

Abstract: A protection and operation system and method is provided for a high voltage power supply of an electrostatic precipitator by protecting the power supply from overload when current demand becomes too high, including due to electrode contamination, including during arcing conduction, including plasma conduction.

Abstract: In an internal combustion engine electrostatic crankcase ventilation system, an EDC, electrostatic droplet collector, assembly includes a replaceable electrode assembly.

Abstract: A multistage space-efficient electrostatic collector cleans a gas flowing therethrough along a gas flow path having a first stage provided by a first corona discharge zone along the gas flow path, and a second stage provided by a second corona discharge zone along the gas flow path and spaced along the gas flow path from the first corona discharge zone. A method is provided for increasing residence time within the corona discharge zone of gas flowing through an electrostatic collector.

Abstract: An electrostatic precipitator has a collector electrode collecting particulate ionized in an electric field created by a high voltage corona discharge electrode pulse energized by a pulsed high voltage power supply. The corona discharge electrode is pulsed between a baseline voltage and a peak pulse voltage.

Abstract: A corona discharge electrode assembly is provided for an electrostatic precipitator, including for a diesel engine electrostatic crankcase ventilation system for blowby gas, having a collector electrode spaced from a discharge electrode by a gap to facilitate corona discharge therebetween. The corona discharge electrode assembly includes a drum having strips, louvers or spikes providing corona discharge tips.