Performance Characterization of a Thermal Regeneration Unit for Exhaust Emissions Controls Systems 2011-01-2208
Diesel Particulate Filters have been successfully applied for several years to reduce Particulate Matter (PM) emissions from on-highway applications, and similar products are now also applied in off-highway markets and retrofit solutions. As soot accumulates on the filter, backpressure increases, and eventually exhaust temperatures are elevated to burn off the soot, actively or passively. Unfortunately, in many real-world instances, some duty cycles never achieve necessary temperatures, and the ability of the engine and/or catalyst to elevate exhaust temperatures can be problematic, resulting in overloaded filters that have become clogged, necessitating service attention. An autonomous heat source is developed to eliminate such risks, applying an ignition-based combustor that leverages the current diesel fuel supply, providing necessary temperatures when needed, regardless of engine operating conditions. The approach taken in the design and development of this thermal regenerator, including its performance targets applied to compete with current catalyst-based technologies, such as pressure drop, temperature dependencies, thermal power capacity and efficiency, flow and temperature uniformity, packaging, and durability. Components necessary to support the operations of the thermal regenerator are described, as well as the system's general functionality. In conclusion, the capability of the thermal regenerator is established, including extreme transient response, offering viable solutions for problematic applications, minimizing regeneration risks without compromising system performance, as evidenced with several described demonstrator vehicles.