Originally posted by repsa
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Tässä on esimerkiksi jonkun volvon regenerointi. Tuossa hehkut killittää päällä tämän tästä ja egr:ää pidetään myös raollaan. Samoin kaasuläppää kuristetaan ajoittain. EGR venttiilin asennossa näkyy myös piikkejä ja luulen että se johtuu siitä että kun mennään moottorijarrulle niin tällöin egr läväytetään auki jolloin saadaan lämmöt pysymään paremmin ylhäällä.
Tuosta onkin kirjoitettu esim tässä:
Strategies for Achieving pre DPF Regeneration Temperatures using in Cylinder Post Injection on a Common Rail Diesel Engine with EGR, DOC and Intake Throttle 2010-36-0306
A DPF (Diesel Particulate Filter) is a device designed to remove diesel particulate matter or soot from the exhaust gas of a diesel engine. Wall-flow diesel particulate filters usually remove 85% or more of the soot. In addition to collecting the particulate, a method must exist to clean the filter. Wall-flow filters are designed to burn off the accumulated particulate at regular intervals, and this can be achieved through engine modifications such as in-cylinder post injections, throttling of the intake air, and using the EGR valve during overrun all to achieve 630degC at the DPF.
A DPF (Diesel Particulate Filter) is a device designed to remove diesel particulate matter or soot from the exhaust gas of a diesel engine. Wall-flow diesel particulate filters usually remove 85% or more of the soot. In addition to collecting the particulate, a method must exist to clean the filter. Wall-flow filters are designed to burn off the accumulated particulate at regular intervals, and this can be achieved through engine modifications such as in-cylinder post injections, throttling of the intake air, and using the EGR valve during overrun all to achieve 630degC at the DPF.

Koko lappu: https://sci-hub.se/10.4271/2010-36-0306
Myös tämä herra on loggaillut VAGgilaista pikinytkyä ja todennut että regeneroinnin aika egr on raollaan ja itseasiassa todennut että oli polttoa tai ei niin egr on raollaan samalla tavalla.
Finally, I tested my 1.6TDI CAYC all day long with forced regenerations while driving and while stationary. The conclusion is very simple, DPF regeneration has nothing to do and does not influence in any way the normal management of the engine. The only difference is that, in regeneration mode the injector has up to 3 additional injections, named post-injections. They are "post" because they happen right after the power stroke occurs, exactly on exhaust phase. The fuel injected as a gas cloud goes right into CAT where it burns. (note: at any car, when you start the stationary regeneration you will see smoke coming out of exhaust, because the CAT is cold (only ~200 celsius degrees) and the after burn is incomplete, thus the smoke. like starting a diesel without plugs in the winter).
Considering the conditions for DPF regeneration when stationary (no load, 1500-2000rpm at VAG Euro5 at least) the EGR is partially open, having measured 250mg/stroke of air. (with EGR off it should be around 450mg/stroke)
Also, considering the conditions for DPF regeneration while driving, the procedure say to run the car in 4th,5th or 6th gear at 2000-3000rpm. I tested in 4th gear at 95km/h @ around 2600rpm. Therefore, the engine has minimum load, it goes under constant circumstances, the EGR is also partially open. (500-600mg/stroke)
It is logically as well. It would be dumb for EGR to remain closed, because it would produce NOx while cleaning DPF. Absolute non-sense.
As a result, the answer is clear for the question: the EGR is partially open during DPF regeneration. Actually, it works similar as if the engine is not in regeneration state.
Considering the conditions for DPF regeneration when stationary (no load, 1500-2000rpm at VAG Euro5 at least) the EGR is partially open, having measured 250mg/stroke of air. (with EGR off it should be around 450mg/stroke)
Also, considering the conditions for DPF regeneration while driving, the procedure say to run the car in 4th,5th or 6th gear at 2000-3000rpm. I tested in 4th gear at 95km/h @ around 2600rpm. Therefore, the engine has minimum load, it goes under constant circumstances, the EGR is also partially open. (500-600mg/stroke)
It is logically as well. It would be dumb for EGR to remain closed, because it would produce NOx while cleaning DPF. Absolute non-sense.
As a result, the answer is clear for the question: the EGR is partially open during DPF regeneration. Actually, it works similar as if the engine is not in regeneration state.
Kaasuläpän sulkemiskartan moottorijarrutuksessa regeneroinnissa löysin jo tuolta mutta EGR osuus on vielä pimennossa.

Näköjään EDC17CP45 ja EDC17CP46 toimintakuvaukset näyttävät olevan hyvin samakaltaiset. Tuossa boschin dokkarissa on vaan noin 10000 sivua niin sieltä ei ole kovin helppo löytää niitä asioita mitkä kiinnostavat. Saattaa kuitenkin olla että tuolta jostain löytyy se haluttu asia.




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