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Christ no offense, but don't take wikipedia as gospel. It is often changed by people who don't know what they are talking about or change the facts to meet their misconceptions.
For example, the last thing any engine manufacture wants to do is generate any form of nitrous oxides before flowing out of the cylinder. If there is NO2 being formed even more NOx is being formed. Secondly the main thing that plugs up a DPF is carbon soot and the only thing that is really effective at burning it out is lots of heat and O2. Finally sulfur doesn't interfere with regeneration. Sulfur leads to increased soot emissions which will exacerbate the plugging problem however the big problem with sulfur is that it poisons the catalyst that is used to reduce NOx into NO2.
When a regeneration cycle takes place in a modern diesel with a DPF, a small amount of fuel is injected during the power stroke late in the cycle. This is done so that not all of the fuel burns and that which is has little power extracted from it. Its sole purpose is to heat the exhaust as much as possible (Note that diesels normally have extremely low hydro carbon emissions). The fuel that isn't burned hits a dual purpose catalyst that is supposed to burn of the remaining hydrocarbons and also convert NOx to NO2. It also raises the exhaust temps further before getting to the DPF. Any O2 left in the exhaust will then burn off the carbon in the DPF (Also note to enrich the amount of O2 in the exhaust during regeneration cycles EGR is reduced which increases NOx levels produced and thus emitted).
My car was built before common rail injection and can't do a regeneration cycle. The only thing that can get my DPF clean is sustained hard driving. Also the thing that tends to plug it up the most is efficient driving around town.
Normally in the summer my car doesn't plug up at speeds above 45mph and does regenerate the DPF at speeds above 60mph. However in winter with the cooler intake air combined with the lower btu content of winter diesel fuel my car doesn't plug at 70mph. The only thing I can do to start regenerating it is to floor it up long steep hills at 80+.
Finally my car driving in 1st at 4000 rpm is going to generate about 5 to 7 psi of boost. This is going to force so much excess air into my cylinders that my exhaust temperatures will drop below what they would be driving my car around in drive. It will also burn more fuel, wear out my engine, and create more CO2 not to mention cost me a lot more money. don't take wikipedia as gospel. It is often changed by people who don't know what they are talking about or twist the facts to match their misconceptions.
For example, the last thing any engine manufacture wants to do is generate any form of nitrous oxides before flowing out of the cylinder. If there is NO2 being formed even more NOx is being formed. Secondly the main thing that plugs up a DPF is carbon soot and the only thing that is really effective at burning it out is lots of heat and O2. Finally sulfur doesn't interfere with regeneration. Sulfur leads to increased soot emissions which will exacerbate the plugging problem however the big problem with sulfur is that it poisons the catalyst that is used to reduce NOx into NO2.
When a regeneration cycle takes place in a modern diesel with a DPF, a small amount of fuel is injected during the power stroke late in the cycle. This is done so that not all of the fuel burns and that which is has little power extracted from it. Its sole purpose is to heat the exhaust as much as possible (Note that diesels normally have extremely low hydro carbon emissions). The fuel that isn't burned hits a dual purpose catalyst that is supposed to burn of the remaining hydrocarbons and also convert NOx to NO2. It also raises the exhaust temps further before getting to the DPF. Any O2 left in the exhaust will then burn off the carbon in the DPF (Also note to enrich the amount of O2 in the exhaust during regeneration cycles EGR is reduced which increases NOx levels produced and thus emitted).
My car was built before common rail injection and can't do a regeneration cycle. The only thing that can get my DPF clean is sustained hard driving. Also the thing that tends to plug it up the most is efficient driving around town.
Normally in the summer my car doesn't plug up at speeds above 45mph and does regenerate the DPF at speeds above 60mph. However in winter with the cooler intake air combined with the lower btu content of winter diesel fuel my car doesn't plug at 70mph. The only thing I can do to start regenerating it is to floor it up long steep hills at 80+.
Combustion in a diesel is quite different than a gasoline engine. Unless over fueled or smothered by excessive EGR, atomized fuel droplets fly through compressed heated air surrounded by a boundary layer of mixture that is near optimum for combustion. They continue until they burn themselves out of existence. This is why a diesel can run air fuel mixtures of 20 to well over 100 to 1 and gas engines can't. Assuming you have about 15% excess air in both cases, using the same amount of fuel in a diesel with higher air to fuel ratios drops your exhaust gas temperatures in comparison to a lower ratio.
Finally my car driving in 1st at 4000 rpm is going to generate about 5 to 7 psi of boost. This is going to force so much excess air into my cylinders that my exhaust temperatures will drop below what they would be driving my car around in drive. It will also burn more fuel, wear out my engine, and create more CO2 not to mention cost me a lot more money.
Not going to happen...
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