1、13thAnnual OSAR Conference,3/2024An Update on the Examination of In-Use Measurement Variation with PEMS at Low NOXLevelsChristopher Sharp13thAnnual International OSAR ConferenceMarch 14,2024113thAnnual OSAR Conference,3/2024Background Low NOXlevels(MY 2027 and beyond)will present new challenges to P
2、EMS Lower levels 50 mg/hp-hr 2B-MAW analysis method PEMS equipment have evolved(and improved)since original Measurement Allowance in 2006 Objective:Update assessment of PEMS Measurement error and variations Provide information for update of PEMS Accuracy Margins Use a Monte Carlo Model based approac
3、h213thAnnual OSAR Conference,3/2024EPA Stage 3RW Low NOXDemonstration Engine2017 Cummins X15 EngineAdvanced Low NOXAftertreatment(Dual SCR-Dual Dosing)Additional Engine Hardware(Cylinder Deactivation)Development Targets:FTP/RMC NOX0.02 g/hp-hr at 435k milesLowest feasible LLC and in-use NOXNo advers
4、e GHG impactEaton CDA HardwareSAE Papers2021-01-05892023-01-03573EPA UpdatesChanged zCSF to DOC+DPFImproved downstream DEF mixingHeated Doser(Forvia)500 hp/1850 lb-ftEfficiency Series13thAnnual OSAR Conference,3/2024Real-World Duty Cycles Each of these cycles is a real working route that was driven
5、with multiple actual Class 7 and Class 8 trucks Cycles represented a wide variety of different kinds of vehicle operations Recorded Vehicle Data was used to develop speed/load profiles that could be translated for Laboratory use4CARB Southern NTE RouteWVU Grocery Delivery RouteWVU EU-ISC RouteWVU Dr
6、ayage Route7.50.71.51.10.43.30.150.060.0480.0460.0470.0290.0330.0230.0350.0290.0460.0220.000.020.040.060.080.100.120.140.160.180.20024681012Bin 1-IdleBin2-LowBin 3-Mid-HighBin 2/3 NOX,g/hp-hrBin 1 NOX,g/hr2031-StdSNTEmACESDrayageEU-ISCGrocery800k Miles13thAnnual OSAR Conference,3/2024Cycle Translati