Advanced Lean Burn Micro- CHP Genset - ARPA-E · 2020. 9. 3. · Advanced Lean Burn Micro-CHP...
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Advanced Lean Burn Micro- CHP Genset MAHLE Powertrain (lead) Oak Ridge National Laboratory Intellichoice Energy Louthan Engineering Kohler Company ExxonMobil Research & Engineering Michael Bunce – Principal Investigator [email protected] Louthan Engineering
Transcript of Advanced Lean Burn Micro- CHP Genset - ARPA-E · 2020. 9. 3. · Advanced Lean Burn Micro-CHP...
Advanced Lean Burn Micro-CHP Genset
MAHLE Powertrain (lead)
Oak Ridge National Laboratory
Intellichoice Energy
Louthan Engineering
Kohler Company
ExxonMobil Research & Engineering
Michael Bunce – Principal [email protected]
Louthan Engineering
Project Team
Technology: Proposal
NG-fueled single-cylinder internal combustion engine operating ultra-lean
Prototype engine incorporating MAHLE Jet Ignition® (MJI) system
Incorporates MAHLE lightweight and low friction engine components
Downsped engine to reduce mechanical friction
– Apply low temperature aftertreatment to meet emissions requirements
– Extract heat from exhaust and coolant to provide heat to process water
– Use highly efficient power conversion technologies
Technology: Jet Ignition Benefits of ultra-lean operation
– Favorable thermal
properties of lean charge
– Knock reduction
– Low NOx emissions
MJI: pre-chamber-based
combustion system producing
high ignition energy radical jets
– Amplifies the ignition
energy from the spark
Enables stable ultra-lean
operation
– > 42% BTE in gasoline
passenger car
applications
– < 100ppm engine-out NOx
Technical Progress
Combustion System
– Developed 1D/3D efficiency model with empirical data input from multiple sources
– Model indicates target indicated thermal efficiency of 45% is achievable
– Developed MJI pre-chamber geometry variants
– Identified target FMEP
Engine Design
– Completed prototype single-cylinder design
Design centered around Jet Ignition combustion system
– Targeted subsystems for low friction and long life
Incorporated numerous MAHLE low friction engine components and best practices
Technical Progress
Aftertreatment
– Established anticipated emissions scenarios
– Identified aftertreatment strategies
– Performed bench-scale testing to evaluate strategies
– Best performance: MOC + LNT
Tailpipe NOx, VOC should be below program targets
CO should meet targets
Significant challenge remains for meeting GHG target
– Developed controls parameters for regen cycles
Heat Recovery
– Completed coolant system diagram
– Established system heat analysis
Multiple operating modes
Analysis informs HX component spec
Power Conversion
– Completed system electronics diagram
– Identified power electronics components
Power conversion expected to achieve 95% eff
Bearing-less alternator design
SiC DC-to-AC conversion components
Technical Progress
Lessons Learned
Combustion System
Model validity decreases when attempting to capture ultra-lean low heat loss conditions
– Heat transfer models
– Fuel chemical kinetics models for CNG
Engine Design
Single cylinder engine friction data of this size class is not widely available, therefore empirical friction modelling is challenging
“Infinite life” durability predictions are well established for some engine components and subsystems, not well developed for others makes comprehensive “infinite engine life” predictions challenging
– Cyclic fatigue predictions well established
– Component wear predictions are not wear over 80,000 hours
Typical durability testing = 2500-5000 hours
Lessons Learned
Aftertreatment
Low temperature CH4 conversion is challenging using state-of-the-industry catalysts
Anticipated ultra-lean engine exhaust NOx concentrations of 15-20 ppm are still too high to meet program targets
– Commercially available urea dosing systems are unable to reliably deliver the extremely low flowrates required for a small engine with ultra-low NOx emissions
– Low NOx concentrations create opportunities for other non-urea NOx control strategies such as lean NOx traps and passive SCR
Power Conversion
Challenges identifying subsystem suppliers willing to support development/prototype efforts, primarily budgetary
Need to maintain communication concerning subsystem interaction / interface
Next Steps2017 activities mainly focus on procurement, testing, and system integration
Engine
Procure engine components and complete engine build
Test engine to establish baseline lean limit, efficiency, and emissions
Evaluate engine durability
Lubricants
Develop lubricant formulations for long engine life, low friction, and catalyst health
Perform lubricant testing on-engine
Aftertreatment
Scale up selected catalysts for lab-scale testing
Test regen cycle control routine on-engine
Deliver final aftertreatment hardware
Next Steps2017 activities mainly focus on procurement, testing, and system integration
Heat Recovery
Procure and build heat exchangers
Heat exchanger bench testing
Deliver final heat exchanger hardware
Power Electronics
Procure and deliver power conversion components
System
Integrate all subsystems and test complete system performance
Tech-to-Market
Evaluate partner commercial interests in system / concepts at each milestone
Continue developing Techno-economic analysis
