Regeneration Rate
Regeneration cycles are planned to happen on a regular basis. Depending on the engine, its power ratings, how the engine is being driven, and the kind of DPF, these predetermined intervals may occur as frequently as once every hour or as infrequently as once every eight hours of operation. The anticipated intervals between the regeneration cycles of the equipment that truck drivers operate should be disclosed. The temperature of the exhaust gases will rise during both passive and active regeneration, so the driver may always stop the regen.
cyclic regeneration
In order to describe regeneration cycles, we will take the DPF of one engine manufacturer as a reference: This OEM utilizes spark assist for active regens but otherwise follows standard practice in the sector:
1.Passive regeneration is when regeneration takes place without the aid of a flame burn-off cycle because exhaust temperatures are high enough to allow for it. When the car is traveling down the highway with the engine running hard, this is supposed to be the main method of DPF regeneration. In this regen mode, DPF soot is oxidized (burned) to produce nitrogen, CO2, and ash leftovers using engine out NOx and exhaust heat. Typically, The typical passive cycle of regeneration is intended to happen just about once every eight hours. DPF temperatures can rise beyond 600°C (1,112°F) during this typical passive cycle.
- Passive plus: This is intended to happen when the soot accumulation reaches 125% and the DPF is starting to get constrained, which happens after an extended period of idling. Compared to the typical passive regeneration cycle, this method of passive regeneration takes place at a significantly lower temperature. Spark ignition and a little amount of diesel are required (far less than in active transient mode). To keep things as they are, it is necessary to burn off a small amount of soot about every two hours. DPF output temperatures during passive plus regeneration should not rise over 400°C (752°F).
- Active transient: This is scheduled to happen when the DPF is starting to get limited and soot levels are at 100%. An active transient burn cycle won’t start unless the car is moving faster than 20 mph (32 km/h).
- Active steady state: This can be controlled by a dash button or the engine diagnostic software. The car must be in park and traveling at a speed of 0 mph (km/h). A spark ignites the diesel once it has been injected.
Transient regeneration events will not occur when:
- Ambient temperatures are less than 20°C (68°F), transient regeneration events will not take place.
- The temperature at turbo-out surpasses 550 °C (1,022 °F) (because passive regeneration is possible)
- The coolant is not above 65 °C (150 °F)
Regeneration system (RS) warnings, which the engine ECM broadcasts on the data bus:
Once the soot content reaches 100%: The RS light shines.
A soot level of more than 125%: RS light flashes.
If the soot level is greater than 150%: 25% engine derates
If the soot level is greater than 175%: 75% of the engine derates
If the soot level is greater than 200%: engine extinguishes
The heat necessary to perform the soot burn-off is derived from the exhaust gas emitted from the engine cylinders on DPFs that do not employ spark aid during active regeneration events; an afterburn pulse of injected fuel may be used.
Regeneration System Hardware
An RS head with the following features makes up the RS hardware:
- An injector of gasoline
- A swirler plate
- An ignition plug
- Ports for cooling systems
The low-pressure injectors used in gasoline fuel injection can be used to compare the fuel injector nozzle: the fuel injector is supplied by the diesel fuel subsystem at its specified charging pressure, which is why some OEMs have significantly increased fuel subsystem charging pressures in their post-2007 products. A damaged fuel injector is typically irreparable, necessitating the replacement of the whole RS head..
The CRS spark plug is made up just of an electrode (does not self-ground). Its intended destination is a swirler plate that is situated right underneath it. The ECM controls the timing of the spark plugs. Every time the head is taken off, the gasket has to be replaced since it serves as an insulator.
