Volvo EPA2007 D13F - Exhaust Aftertreatment System; Exhaust Gas Recirculation; Particulate Matter

ENGINECOMPONENTANDLOCATION107
EGRCooler
TheEGRvalveisconnectedtotheEGRcoolerbythecoolerinletpipe.Using
enginecoolant,theEGRcoolerlowersthetemperatureofthegascomingfromthe
EGRvalve.Thecoolercontainsaseriesofvanesthatincreasecoolingefciencyby
swirlingthehotgasbeforeitentersthemixer.
EGRVenturiSystem
OnleavingtheEGRcooler,thegasowsthroughaventuriequippedwithtwo
pressuresensors.Theventurichangesthespeedanddensityoftheow.Thesensors
reportthepressuredifferencetotheEECU.
EGRCoolerOutletPipe
TheEGRcooleroutletpipecarriestheexhaustgasfromtheventuritothemixer.
Relativelyshort,thetubepassesoverthevalvecover,behindandintothemixeratthe
frontendoftheinletmanifoldontheconventionalchassisengine.
RelativelymuchlongerontheLCF,thetubepassesfromtheventuriaroundthefront
ofthevalvecoverandreachesbacktothemixerattherearendoftheinletmanifold.
AtemperaturesensormonitorsexhausttemperaturesendingthedatatotheEECU.
Excessivelyhightemperature,orabnormallyhightemperatureformorethan30
minutesduringanhour,causestheEECUtolimitenginepowertopreventengine
damage.
EGRMixer
TheEGRmixeristhemeetingpointforcooled,recirculatingexhaustgasandoutside
airfromtheCAC.Fromhere,thecombinedgasespassintotheinletmanifoldand
ontothecombustionchamber.