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This research introduces a new, novel approach to reverse flow particulate filter regeneration enabled by rapidly pulsed electric discharges. The discharges physically dislodge particulate matter (PM) from the filter substrate and allow a very low reverse air flow to transport it to a soot handling system. The system is operable independent of filter temperature, does not expose the filter to high thermal stresses or temperatures, has no apparent upper limit for filter PM-mass level (regeneration of a filter up to 17 g/L has been demonstrated), and does not require any catalyst. The system is inherently scalable allowing application to monolithic filters of any size or shape and can be tailored to suit specific application requirements such as limits on maximum regeneration time or power consumption. For example a light duty application would require as little as 200-500W electrical power to regenerate a filter in less than ten minutes (i.e. passenger car GPF or DPF).

Stringent IC engine PM emission regulation requires development of future filter substrate materials to achieve high filtration efficiency, low filter pressure drop, low cost and highly durable solutions. Monolithic wall flow filters perform well as they achieve high filtration efficiency due to the formation of the PM cake structure while maintaining low substrate face velocities due to the large filtration area. Within the process industry, Micropore™ slotted metallic membrane filters offer both large surface areas and low filter pressure drops while maintaining the durability of metal substrates. The pore structure and pore arrangement can be readily tailored to suit specific applications. This paper characterizes a 300 μm thickness Micropore™ metallic membrane with slots of 10 μm by 400 μm in size in the context of application as an engine exhaust particulate filter. The investigation was based on single layer of Micropore™ slotted metallic membrane with size of 52 mm in diameter.

Modelling of turbochargers based on steady state operating maps for turbine and compressor rotors is widely recognized to have limitations arising from flow pulsations and heat transfer effects that are not well accounted for by interpolation and extrapolation from the mapped data. With implementation of low pressure exhaust gas recirculation systems and multi-stage boosting, the inlet conditions of centrifugal compressors vary more widely than traditional single stage compression systems. Understanding the impact of the inlet conditions on irreversibilities, and therefore efficiency complements existing works on pulse flow and heat transfer effects in informing the engine modelling community. This research experimentally explores the effect of inlet pressure and temperature on the total-total efficiency of a steady flow centrifugal compressor across a range of conditions in isolation of pulse flow effects and with negligible heat transfer.