1DepartmentHoushun Zhang, Yury Kalish, Marc Allain, Guangsheng Zhu, and Zhiping HanAugust 6, 2008Daimler Trucks2Program OverviewTechnical DetailsAdvanced Fuel Injection SystemCombustion OptimizationAdvanced Next Generation ControlSummaryOutlineDaimler Trucks3Program ObjectivesExplore advancements in engine combustion systems using high-efficiencyclean combustion (HECC) techniques to minimize cylinder-out emissions whileoptimizing engine fuel economyMaximize thermal efficiency with integrated engine and DPF+SCRaftertreamtent system while meeting 2010 emission regulationsEmphasis on Enabling Sub-systemTechnologies•Advanced combustion systemtechnologies•Flexible, precise fuel injection•Air and EGR system technologies•Advanced multiple input multiple outputcontrol technologiesDaimler Trucks4System Development ApproachEvaluation on truck operation for overalltechnology assessment and refinementExample Operating ConditionsOver Truck RoutesRPM 

# LOAD (%)TailpipeDPFSCRSelecting road-load operatingconditionsIntegrated AnalyticalSimulation ToolsComponent OptimizationSteady State and TransientDynamometer TestingIntegration of aftertreatmentsystemsFocus on integrated engine and DPF+SCR system,maximizing thermal efficiencywhile meeting 2010 emissionsDaimler Trucks5Production engineDemo engineCurrent project:Combustion focus•High efficiency clean combustion•Dual-mode combustion•Variable fuel injection•Basic energy recovery•Advanced controlPrevious project:Total engine systemimprovementsFuture project:complete engine system•Next gen. variable fuel injection•Multi-mode combustion•Variable breathing technologies•Advanced control•Advanced Energy recovery•Engine + DPF+SCR integration•Powertrain integrationThermal EfficiencyRoadmapDaimler Trucks6Advanced Fuel Injection SystemAdvanced fuel injection with full flexibility of injection eventswas procured and being evaluated.System combines unit injectors and an accumulator railMedium pressure rail (up to 1000 bar) to provide early / lateinjection eventsUnit injector to provide high pressure short duration maininjectionCombined rail / unit injector operation for boot shape and closepilot / post injectionsUnit injectors to act as rail pressure source (no rail pumprequired)DelphiDaimler Trucks7Variable Nozzle TechnologyIntroduced variable fuel injection technology into the program with highpotential to significantly enhance high efficiency clean combustion.Great potentials have been demonstrated analytically throughout differentspeeds and loadsSignificant fuel economy improvement, ranging from 5% to 12%Substantial NOx and soot emission reductions, ranging from 50% to90%Variable nozzles have been procured, and assembled with advanced fuelinjection system.Flow bench tests are underway, and the engine tests will follow soon.Daimler Trucks8QLCQuantLogic Corp.Micro-Variable Circular Orifice (MVCO)First phase injection with conical sprayand narrow spray angle produced byMVCO NozzleSecond phase injection with multi-jet sprayand wide spray angle produced byMVCO NozzleDaimler Trucks9BaselineOptimumAdvanced Combustion DevelopmentAutomated selectionof engine operatingparameters foroptimal emissionsreductionGenetic combustion optimizationFuel injection and piston bowloptimizationNew combustion concept explorationMulti-mode combustion with advancedfuel injection system and variablenozzle technologyReal time combustion controlIn-cylinder pressure sensorionization sensorsDaimler Trucks10Specific Combustion Optimization on PCCIrun Soot NOx gisfc Fuel economyimprovementg/kgf g/kgf g/kW-hr %base0.23 3.24 233.3 -10.12 5.27 201.1 13.820.41 7.76 223.0 4.4---------- ----- ----- -----110.33 1.98 212.9 8.712 0.19 3.72 208.1 10.8The objective is to achieve similar soot and NOx emissions to that of thebaseline case but with a ~10% fuel consumption improvement10.8% fuel economy improvementwas obtained while maintainingthe same emission level asbaseline.Engine testing is just under way and preliminary results show 5.03%BSFC improvement. More tests will be reported soon.Daimler Trucks11SetpointsSPEEDFUELBSFCNOxPMHCCOTorqueCONTROLLERModel BasedControllerEngineModelEngineActuatorsEngineSensorsPositionFeedback+-AftertreatmentModel+-+-AdaptationEmissionsModel. Hot. Cold. Transient. Altitude. Smoke control. Regeneration. AgingReal-TimeOptimizer			
	
	


	
Physicaland VirtualDaimler Trucks12Application of Transient Calibration Optimization to FTP CycleEach point marker designates onecalibration FTP set point4% Thermal Efficiency ImprovementWith Next Generation Model Based ControllerAnd 15% NOx and 25% PM ReductionSimultaneouslyDaimler Trucks13Transient Calibration Optimization (FTP Tests)Next Generation Model Based Controller breaks traditional BSFC-NOx Trade-off Curve toward more Fuel Economy ImprovementDaimler Trucks14Barriers/ChallengesTechnical challenges with variable nozzle technology are enormousNeedle lift controlHigh sensitivity to needle position – design may not be robust to tolerancesVery high precision required in manufactureCombustion mode transitionNeed robust controls methodologiesNext generation model based controlComputational power and speed in engine control unitModel integration complexity with real time engine, aftertreatment, andemission model that must be adaptive, robust, and precisionDaimler Trucks15SummaryProgram is progressing well and aggressively. It is toward meeting the programobjective with 10% thermal efficiency improvement by 2009.Identified key enabling technologies with high potential returnsAdvanced fuel injection system coupled with variable fuel injection nozzleGenetic combustion system optimizationTransient control optimizationSignificant benefits with advanced fuel injection system and variable nozzletechnology have been demonstrated. A new combustion strategy covering theentire operating range is emerging.Daimler Trucks16AcknowledgementsDepartment of Energy HeadquartersGurpreet SinghRoland GravelNational Energy Technology LaboratoryCarl MarondeJeffrey Kooser