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The connecting rod big-end bearing is one of the most heavily loaded components of the lubrication system of high speed combustion engines. The bearing's oil supply has to be designed consciantious in order to ensure an immaculate reliability in operation. The supply oil flow has to pass the main bearing and the rotating crankshaft before entering the connecting rod bearing. It is common knowledge that the centrifugal forces due to the crankshaft rotation influence the oil flow through the also rotating supply bore. The centrifugal forces effect a parabolic pressure profile along the supply bore. The oil pump has to ensure a certain pressure level in the main oil gallery (depending on the engine speed and the spherical positioning of the rotating bore) to overcome these centrifugal forces. If the oil pressure is lower than this certain level the bearing's oil supply will be interrupted - bearing damage is the consequence.

A modular particulate trap system for buses, trucks and other applications consiting of honeycomb traps and an electrical regeneration system has been designed and tested on a test bench and in a city bus. For regeneration, the soot is ignited at the entrance of the trap channel by electric heaters. After ignition, the soot burns self-supporting without further energy supply. Regeneration is possible over the whole engine map. The electrical energy consumption of the heaters for a city bus is in average below 100 W. The filtration efficiency of the system including regeneration is about 80 % during transient city driving. During regeneration, appr. 98 % of the accumulated hydrocarbons adsobed to the soot in the trap are burned off the initiated combustion front. Additionally, the odor of the diesel engine exhaust gas behind the trap is lowered at low engine load even during regeneration.

Diesel soot collected in a catalytically coated ceramic honeycomb trap, burns self-supporting, if the heat loss is less than the heat release due to soot oxidation. Experimental verification has been accomplished using a 4.66″ × 6″, 100 CPI trap. Ignition time and regeneration time are measured. At low speeds, a minimum ignition time of 15 s would be sufficient for the trap regeneration. An extended channel with an observation window is provided to allow examination of the regeneration. The soot is ignited at the beginning of the channel and the flame propagation is then observed. The soot burns through the channel in a match-like manner. Manganese and iron fuel additives are observed to have an effect on the mechanism of flame propagation.

Particulate emissions from diesel engines mainly consist of soot and high-boiling hydrocarbons (volatile fraction). To reduce the volatile fraction different precious metals and their combinations are tested in traps and supports especially at low loads. A sufficient catalyst's efficiency at low exhaust-gas temperatures (low load) requires a large active catalyst surface. Due to the soot in the diesel exhaust-gas, the catalyst can be covered by a soot layer reducing the catalyst's efficiency. The accumulated soot in the trap must be oxidized. Nonprecious metal catalysts are able to lower the soot ignition temperature. The reduction in ignition temperature depends on the catalyst material used. The influence of the catalyst's concentration and the use of an additional washcoat are also investigated.

Low pollution emissions of stratified-charge engines and fuel economy of Diesel engines were incorporated into a stratified-charge Diesel engine with direct fuel injection. Tests and evaluation of this engine form the basis of the investigation. The paper is divided into two main parts. The first describes particular components and parameters: combustion chamber, injection jets, combustion air spin, timing, partial carburetion during optional gasoline operation, and throttling of intake air. The second part discusses these individual topics in light of the test results.