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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.

Current and future emission levels on Particulate Matter (PM) will require diesel engines to use Diesel Particulate Filters (DPF). One of the challenges of using a DPF is the requirement to generate high temperature exhaust flow (typically 550 - 650 degrees C) to enable filter regeneration, especially at cold temperatures and transient conditions. Maintaining constant temperature and low emissions during regeneration presents a number of controls challenges. This is especially true for burner systems which have complex air, fuel, and ignition systems. This paper outlines the controls and diagnostics of a burner system. Details of the burner system component modeling, thermal modeling of combustion, combustion flame detection, and system control and diagnostics are also illustrated. Application data is presented to demonstrate performance and robustness of the system at different engine conditions.

A student design team at Colorado State University (CSU) has developed an innovative snowmobile to compete in the Clean Snowmobile Challenge 2002 competition. The team selected a 600cc two-stroke cycle engine (Arctic Cat ZRT600) due to its favorable power/weight ratio. In order to reduce emissions, the team adapted the engine to operate with direct in-cylinder fuel injection, using the Orbital Combustion Process (OCP) air-assisted fuel injection system. This conversion required that the team design and cast new heads for the engine. The direct-injection system reduced carbon monoxide (CO) emissions by 70% and total hydrocarbon (THC) emissions by 90%. An oxidation catalyst was placed in the engine's silencer to oxidize the remaining CO and hydrocarbons. The combination of direct injection and oxidation catalyst reduced both CO and THC by over 99%. In order to reduce noise, the team switched from the use of three expansion chambers (i.e.