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Operational Diesel Particulate Filter (DPF) technology traps and oxidizes soot particulate, lowering particulate emissions. Additionally they trap other non combustible material which is deposited as ash within the filter. The trapping of this material leads to increased backpressure on the engine, giving an increase in fuel consumption, and requires periodic servicing to remove. This work demonstrates the emission effects of this increase in backpressure and develops a method of realistically accelerating this ash deposition mechanism yielding a bench test for the study of this phenomenon.

The tightening legislation in the on-road heavy-duty diesel area means that pollution control systems will soon be widely introduced on such engines. A number of different aftertreatment systems are currently being considered to meet the incoming legislation, including Diesel Particulate Filters (DPF), Diesel Oxidation Catalysts (DOC) and Selective Catalytic Reduction (SCR) systems. Relatively little is known about the interactions between lubricant-derived species and such aftertreatment systems. This paper describes the results of an experimental program carried out to investigate these interactions within DPF, DOC and SCR systems on a state-of-the-art 9 litre engine. The influence of lubricant composition and lube oil ash level was investigated on the different catalyst systems. In order to reduce costs and to speed up testing, test oil was dosed into the fuel. Tests without dosing lubricant into the fuel were also run.

Battery cell operating characteristics were determined for a unique load profile planned for the Motorola Iridium™ spacecraft. The Iridium™ mission requires that the battery be on line at all times and operated for extended periods with a short duration, high rate, charge/discharge duty cycle. The effort reported here reflects a repetitive duty cycle of 1.3 milliseconds discharge and 2.9 milliseconds charge, with discharge rates in the range 2.0 C to 3.0 C and charge rates in the range 0.9 C to 1.4 C. Cell transient characteristics were determined for candidate cell types including nickel-hydrogen individual pressure vessel (IPV), nickel-hydrogen common pressure vessel (CPV), Super nickel-cadmium, and fiber nickel-cadmium (FNC). Experimental approach, cell performance data, derived transient characteristics, and cell electrical models are presented.