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]

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Topics• Off-Road Characteristics

– Equipment– Engines– Fuel Systems

• EPA’s Exhaust Regulations – Impact on Air-Fuel Ratio Settings

• Summary of Existing E-20 Studies

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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

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Topics (cont.)

• Illustrative Example – Handheld Engines

• Fuel Specification Issues

• Additional Technical Slides/Discussion

Off-Road Characteristics

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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

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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

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Engines (cont.)• Various Engine “Control” Technologies

– Mostly open loop with no feedback– Few closed loop

• Various Emissions Reduction Strategies/Technologies

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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

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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

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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

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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

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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

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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

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E-20 Implications on Engine Durability

Cylinder head gasket burned

Lost seal

Exhaust leak out

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Cylinder head gasket burned

Lost seal


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Cylinder Bore scoring

Deposits


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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

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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.

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Carburetor welch plug epoxy attacked by E20 in 17 wks. Fuel containment seal.

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Fuel Cap gasket swelled & warped by E20 in 1 wk. Fuel containment seal & tank venting.

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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.

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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

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Publication SAE 920164

• Concluded that ethanol has an adverse effect on evaporative permeation emissions from current fuel tanks and hoses

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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

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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

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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

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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

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Technology Categories - Fuel Delivery Systems

• Carburetion– Float type– Diaphragm type– Single vs. multi-circuit

• Fuel Injection– Open loop– Closed loop

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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)

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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

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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

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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

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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

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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.

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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.

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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

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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

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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

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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)

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2005 Diversity - SnowmobilesCategory Recreation Vehicle - Snowmobile

Emission Classes -


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

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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

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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

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2005 Diversity - MarineCategory Marine

Emission Classes -


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

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2005 Diversity – Large SICategory LSI

Emission Classes -


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

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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

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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.

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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)

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...