Minnesota E-20 Fuel Waiver Test Program Technical Presentation Dr. Ranajit (Ron) Sahu, Consultant...
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Transcript of Minnesota E-20 Fuel Waiver Test Program Technical Presentation Dr. Ranajit (Ron) Sahu, Consultant...
Minnesota E-20 Fuel Waiver Test Program
Technical Presentation
Dr. Ranajit (Ron) Sahu, ConsultantPhone: (626) 382 [email protected]
2
Topics• Off-Road Characteristics
– Equipment– Engines– Fuel Systems
• EPA’s Exhaust Regulations – Impact on Air-Fuel Ratio Settings
• Summary of Existing E-20 Studies
3
Topics (cont.)• General Testing Issues to Meet Waiver Criteria
– Creating technology categories to respond to diversity
• Existing and newly regulated products• Engine technologies/materials/components
– Statistically valid data– Pass/Fail criteria
• Testing Evaluations/Criteria– Impact on exhaust and evaporative emissions– Impact on materials compatibility– Impact on drivability/functionality
4
Topics (cont.)
• Illustrative Example – Handheld Engines
• Fuel Specification Issues
• Additional Technical Slides/Discussion
Off-Road Characteristics
6
Equipment• Diversity
– Components, materials, and uses
• Key design issues differ by category– Lawn and garden vs. snow vs. marine etc.
• Seasonal use
• Consumers– Minnesotans own and rely on millions of off-road
engines, vehicles and equipment– Exposed to potential hazards if engine/equipment
operates outside of normal expected conditions
7
Engines
• Air or Water Cooled
• Operator in Close Proximity to Hot Engine/Exhaust System
• 2-Stroke and 4-Stroke – With Variations
• Various Fuel Introduction Technologies– Mostly carbureted with variations– Some fuel injected
8
Engines (cont.)• Various Engine “Control” Technologies
– Mostly open loop with no feedback– Few closed loop
• Various Emissions Reduction Strategies/Technologies
9
Fuel Systems
• Wide variety of tank and hose materials
• Different evaporative control strategies – Permeation, tank venting, etc.
• Multi-positional operational requirements
• Storage-stability issues due to seasonal usage
• Safety constraints
• EPA evaporative/permeation regulations
EPA’s Exhaust Regulations: Impact on Air-Fuel Ratio Settings
11
Regulations SummaryEQUIPMENT/ENGINE TYPE
CURRENTEFFECTIVE
REGULATIONS
FUTUREADOPTED
STANDARDS
ANTICIPATED FUTURE
REGULATIONS
Small Spark Ignition• Lawn & Garden • Other
Exhaust Revised Exhaust / New Evaporative
40 CFR Part 90
Large Spark-Ignition Engines
Exhaust / Evaporative Exhaust/Evaporative
40 CFR Part 1048 2007
Marine Engines Exhaust / Evaporative Exhaust / Evaporative Exhaust / Evaporative
40 CFR Part 91 2006, 2007 Inboard / Stern-drive
Recreational / Vehicles
• Snowmobiles• ATV’s• Off-Road
Motorcycles
Exhaust / Evaporative Exhaust / Evaporative
40 CFR Part 1051 2006, 2007, 2008, 2010, 2012
12
Impact
• EPA’s exhaust emission regulations have resulted in enleanment of the engine’s air-fuel calibration to functional limits
• Fuel management systems cannot effectively manage E0 through E20 fuels interchangeably
• Modification of existing fuel management systems to operate on E-20 would require tampering with an emission control device and thus violate Federal Law
13
Acceptable Operating Range
Limit for Emission Compliance
Limit for Acceptable Operation
Operation on Neat Gasoline
Operation on E10 Gasoline
Operation on E20
Gasoline
Lean Air:Fuel Ratio Rich
14
Exhaust Gas Temperature vs. Fuel Change
1100
1150
1200
1250
1300
1350
0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00
CO %
Exh
au
st
Ga
s T
em
pe
ratu
re -
De
gre
es
F
Change in CO for fuel change from certification to E22 -
Engine M44
CaRFG PH2 Fuel
E22 Fuel
Summary of Existing E20 Experience and Studies
16
E-20’s Impact on Current, Exhaust- Emission Compliant Small Engines
• Exhaust temperatures up 100°F
• Peak cylinder pressures higher
• Combustion deposits
• Cylinder head gasket burned & failed
• Exhaust valve burned
• Cylinder bore scored– 25 hours light duty emissions testing– Lost cylinder compression– Lost 20% power
17
E-20 Implications on Engine Durability
Cylinder head gasket burned
Lost seal
Exhaust leak out
18
Cylinder head gasket burned
Lost seal
E-20 Implications on Engine Durability
19
Cylinder Bore scoring
Deposits
E-20 Implications on Engine Durability
20
Engine Durability Implications with E-20
Head bolts discolored due to heat and carbon build up from exhaust
gas blowing past bolt.
1 7654
1
32 8
21
Engine material compatibility Implications with E-20
Carburetor bowl mounting screw gasket attacked by E20 in few hours. Fuel containment seal.
Bowl gasket swelled & lost seal.
22
Engine material compatibility Implications with E-20
Carburetor welch plug epoxy attacked by E20 in 17 wks. Fuel containment seal.
23
Engine material compatibility Implications with E-20
Fuel Cap gasket swelled & warped by E20 in 1 wk. Fuel containment seal & tank venting.
24
Brazilian Experience• During 1970s and 1980s, blends ranging from E14 – E24
used in Brazilian fuel supply (pre-emission compliant products)
• OPEI Member Experience (2-Stroke engines)– Lean air fuel ratio delivery resulting in
• higher engine temperatures• engine seizures• Poor acceleration performance• Cold start problems
– Phase-separation due to water uptake leading to water in carburetor
– Formation of deposits blocking carburetor nozzles– Corrosion of engine parts, crankcase, bearings, crankshaft, etc.– Had to develop unique products with different carburetor
settings, fuel system materials, etc.
25
Orbital 2002 and 2004; NREL 2002
• E20 requires resizing/recalibration of existing open loop engines (i.e., changed A/F ratio) to prevent – enleanment, resulting in temperature increase, and engine
malfunctions– detrimental impacts on safety
• Detrimental impacts of phase-separation due to presence of water in E-20 – potential engine stall – esp. at cold temperatures
• Poor (Cold) Start performance (esp. important for hand-start engines)
• Hot and Cold performance degraded
26
Publication SAE 920164
• Concluded that ethanol has an adverse effect on evaporative permeation emissions from current fuel tanks and hoses
27
Summary of E-20 Studies
• Causes corrosion of metals and resulting impacts on engine components
• Distorts elastomers and causes resulting impacts on fuel system components
• Causes loss of lubricity due to “cylinder wall wash”• Loosens deposits in existing equipment – leading to
plugged fuel filters etc.• Damage to painted parts• Adverse impact on exhaust and evaporative emissions
and on engine/equipment performance
General Testing Issues to Meet Waiver Criteria
29
Waiver Issues and Test Criteria
1. Exhaust emissions
2. Evaporative emissions
3. Materials compatibility
4. Drivability/Operational Performance and “Tampering” Risk
• EPA must determine whether and when new fuels could cause “failures” in each of these categories
• Data must be derived from unmodified engines, vehicles, and equipment that are EPA-certified, as applicable
• Waiver applicant must evaluate carbureted-engine configurations with their existing air:fuel ratios set for EPA certification fuels
30
Testing - Product Categories
• Since emissions regulations are changing, off-road engines/equipment groups to be tested should include mix of:– Existing, pre-compliant equipment– Existing, EPA compliant equipment
• New• In-use
– Future, prototypical new equipment designed to meet EPA evaporative and exhaust regulations anticipated before 2015
31
Testing - Representativeness Via Technology Categories
• Need to identify and test “representative” mix of engines/equipment
• Must test different “Technology Categories”, based on
• Engine combustion cycle (2 Stroke and 4 Stroke)• Fuel delivery / control systems• Exhaust emission controls/strategies• Evaporative emissions controls/strategies• Equipment use profile
32
Technology Categories - Fuel Delivery Systems
• Carburetion– Float type– Diaphragm type– Single vs. multi-circuit
• Fuel Injection– Open loop– Closed loop
33
Technology Categories – Exhaust Emissions Controls / Strategies
• Various Engine Designs and Modifications– 2 Cycle vs. 4 Cycle– Side vs. overhead valve configurations– Ignition timing changes– Air/Fuel preparation and delivery systems
• Stratification• Compression wave technology
• Catalysts• Hybrids (2/4 Strokes)
34
Illustration of 2005 Exhaust Diversity – EPA Non-Road Small SI Engines
[Additional Illustrations at End of Presentation]
Category Non-Road SI (Handheld and Ground Supported)
Emission Classes I-A, I-B, I, II, III, IV, V
Displacement (cc) 20 - 1000
Useful Life 50-1000 hrs
Engine Cycle 2S, 4S
Fuel Introduction
2S Carbureted, EFI, SFI
4S Carbureted, EFI, SFI
Control Open Loop, O2S/ECM
Valve Location
2S Piston Port (most), Reed
4S Side Valve, Overhead Valve
Emissions Reduction Phase 1, Phase 2
2S EM, EM/TWC, OC, OC-2, TWC, TWC/OC
4S EM, ECM, ECM/O2S, EM/TWC, TWC
35
Technology Categories – Evaporative Materials
• Permeation from– Fuel Tanks made of:
• Metal• HDPE• Barrier Treated HDPE (fluorinated, sulfonated)• Selar• Nylons (various grades)• Coextruded (various types)• Other materials
– Fuel Hoses made of:• NBR• FKM• Other materials
• Venting Emissions from– Uncontrolled venting systems– Carbon Canisters
36
Testing – Statistically Valid Data
• EPA will consider the data’s statistical validity and how well the program represents the product universe– How many different products should be tested?– How many replicate products and repeat
measurements?– How will test data quality be controlled?– Which data points provide statistically significant
results? Which are outliers?– Which statistical tests should be used? etc.
• Statistical expertise helpful in designing the test program and analysis of the results
Testing Evaluations/Criteria
38
Testing – Pass/Fail Criteria
• How will pass/fail criteria be established?– Comparison with EPA standards and
procedures• exhaust emissions• evaporative emissions
– Criteria need to be developed for:• materials compatibility tests• drivability/operability tests
39
Testing Exhaust and Evaporative Emissions
• Goal – Evaluate E-20’s impacts on compliance with emissions standards:– Criteria pollutants (NOx, HC, CO, PMx)
• Test Protocols– EPA exhaust emission test protocols– EPA evaporative emission test protocols– EPA durability/aging provisions
• Pass/Fail criteria – compliance with EPA compliance levels
• Air toxics– e.g, aldehydes, etc.
40
Testing Materials Compatibility• Goal – Assess Short and Long Term E-20 compatibility with
– Metals• Zinc, brass, cast iron, lead, aluminum, magnesium, nickel, etc.
– Non-metallics• NBR, polyurethane, nylons, Viton, Teflon, nitrile, mylar, silicon sealants, felt, etc.
– Adhesives used for labels and decals
• Test Protocols – Need to be developed for various test types below:– Coupon tests– Engine/equipment soak tests under non-operational conditions– Durability tests under nominal operating conditions
• Laboratory (bench) tests• Field tests
– Durability tests under off-nominal operating conditions
• Pass/Fail Criteria – Need to be developed for tests above.
41
Testing “Drivability”• Goal - How does E-20 impact normal operation or
expected normal operation? Specifically, tests should examine– Cold start ability (in all applicable ambient environments)– Load pickup– Acceleration– Hot restartability– Vapor lock – Maximum power operation– Fuel switching: from E-20 to Baseline fuel and vice versa– Impact on safe equipment operation
• Test Protocols – Need to be developed• Pass/Fail Criteria – Need to be developed
Illustrative Example: Handheld Engines
43
Test Categories
Engine/Control Technology Product Type
(current and future) Blower ChainsawTrimmer/
Brushcutter
Pro Pro Consumer Farmer Pro Farmer
2S w/cat Y Y Y Y
Stratified Y Y N N Y N
Stratified w/cat N Y N N
Compression Wave Y
4S Y N N Y N
2S w/tuned exhaust Y Y
44
Test Parameters To Be Measured• Startability• Multipositional stability (@idle, @WOT)• Acceleration• Emissions (new and deteriorated)
– Exhaust– Evaporative/Permeation (Tanks, Lines)
• Power and Torque• Fuel consumption• Plug Seat Temperatures• Exhaust Temperatures• Materials Compatibility Indicators
– Crankshaft assembly (Corrosion)– Cylinder (Corrosion)– Carburetor components (Corrosion/Distortion)– Fuel tanks / Fuel lines / Seals (Distortion)
• Safety Feature Performance
Fuel Specification Issues
46
Testing – Fuel Specifications
• The exact composition of E20 needs to be defined across all appropriate parameter ranges (e.g., ethanol content)
• The exact choices for baseline fuels need to be defined
Additional Technical Slides (future discussion)
48
2005 Diversity - SnowmobilesCategory Recreation Vehicle - Snowmobile
Emission Classes -
Displacement (cc) 120 - 1500
Useful Life 400 hrs // 5 yrs // 8000 km
Engine Cycle 2S, 4S
Fuel Introduction
2S Carb, TBI, Indirect Inj
4S Carb, TBI, Indirect Inj, Port Fuel Inj., EC
Control Open Loop
Valve Location
2S Reed (most), Piston Ported
4S OHV
Emissions Reduction
2S EM
4S EM
49
2005 Diversity – ATV’sCategory Recreational Vehicle - ATV
Emission Classes
Displacement (cc) 50-800
Useful Life 1000 hrs, 10000 km, or 5 years
Engine Cycle 2S, 4S
Fuel Introduction
2S Carb
4S Carb, Inj
Control Open Loop
Valve Location
2S Reed, Piston Ported
4S OHV
Emissions Reduction
2S EM
4S EM
50
2005 Diversity – Off Road MC’sCategory Recreational Vehicle – Off Road Motorcycle
Emission Classes
Displacement (cc) 50-650
Useful Life Earlier of 10000 km or 5 yrs
Engine Cycle 2S, 4S
Fuel Introduction
2S Carb
4S Carb
Control Open Loop
Valve Location
2S Reed Valve, Piston Port
4S OHV
Emissions Reduction
2S EM
4S EM
51
2005 Diversity - MarineCategory Marine
Emission Classes -
Displacement (cc) 60 - 3600
Useful Life PWC/Outboard – 350 hrs/10 yrs, Inboard/Stern Drive – 480 hrs/10 yrs
Engine Cycle 2S, 4S
Fuel Introduction
2S Carb, DI, DI/EC, Indirect Inj/EC, TBI, MPI
4S Carb, Carb/EC, DI, MPI, MPI/EC, Indirect Inj.
Control
Valve Location
2S Reed, PP
4S OHV
Emissions Reduction
2S EM, DFI, Cat, ECM/DFI
4S EM, ECM, SFI, MFI, Cat
52
2005 Diversity – Large SICategory LSI
Emission Classes -
Displacement (cc) 1000 - 6000
Useful Life 7 yrs / 5000 hrs
Engine Cycle 4S
Fuel Introduction
2S n/a
4S Carb, TBI, MPI
Control Open loop, closed loop
Valve Location
2S n/a
4S OHV
Emissions Reduction
2S n/a
4S EM, TWC
53
Specific Test Issues For Fuel Specification
• What is the specification for E-20?– Ethanol should meet ASTM 4806– Fuel as a whole should meet ASTM 4814– Additional denatured ethanol standards (presumably
like CA) need to be met (per RFA)– Specific denaturant specs need to be met
(presumably like CA, per RFA)– Additives should be specified: ignition improvers,
detergents, corrosion inhibitors, anti-foaming agents, demulsifiers, lubricity additives, biocides, etc.
– Finally, certain additional specs (RVP?, distillation curve?, octane?) may need to be met
54
Fuels – Baseline Testing
• What Baseline fuel(s) should be used?– Seasonal/regional baseline fuel blends?– Emissions and emission control systems tests
need to use EPA certification fuels.– For determination of “drivability” and
operability differences, tests need to use E10 as baseline fuel.
55
Fuel Test Specifications• Fuel Characteristics (all Baseline fuels and E-20)
– Ethanol concentration– RVP, boiling curve, Drivability Index– Mixability of oil in fuel– Gum formation– Water content, Corrosion– Octane (RON, MON)– Storability– Autoignition temperature, flash point– Flammability limits– All properties per ASTM 4806 and ASTM 4814– All additional specifications per CARB (and MN, if applicable)