Presentation on theme: "Minnesota E-20 Fuel Waiver Test Program Technical Presentation Dr. Ranajit (Ron) Sahu, Consultant Phone: (626) 382 0001"— Presentation transcript:
Minnesota E-20 Fuel Waiver Test Program Technical Presentation Dr. Ranajit (Ron) Sahu, Consultant Phone: (626)
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
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 Summary EQUIPMENT/ ENGINE TYPE CURRENT EFFECTIVE REGULATIONS FUTURE ADOPTED STANDARDS ANTICIPATED FUTURE REGULATIONS Small Spark Ignition Lawn & Garden Other ExhaustRevised Exhaust / New Evaporative 40 CFR Part 90 Large Spark-Ignition Engines Exhaust / Evaporative 40 CFR Part Marine EnginesExhaust / Evaporative 40 CFR Part , 2007Inboard / Stern-drive Recreational / Vehicles Snowmobiles ATV’s Off-Road Motorcycles Exhaust / Evaporative 40 CFR Part , 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 CO % Exhaust Gas Temperature - Degrees 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
20 Engine Durability Implications with E-20 Head bolts discolored due to heat and carbon build up from exhaust gas blowing past bolt
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 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] CategoryNon-Road SI (Handheld and Ground Supported) Emission ClassesI-A, I-B, I, II, III, IV, V Displacement (cc) Useful Life hrs Engine Cycle2S, 4S Fuel Introduction 2SCarbureted, EFI, SFI 4SCarbureted, EFI, SFI ControlOpen Loop, O2S/ECM Valve Location 2SPiston Port (most), Reed 4SSide Valve, Overhead Valve Emissions ReductionPhase 1, Phase 2 2SEM, EM/TWC, OC, OC-2, TWC, TWC/OC 4SEM, 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
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 TechnologyProduct Type (current and future)BlowerChainsaw Trimmer/ Brushcutter Pro ConsumerFarmerProFarmer 2S w/catY YY Y StratifiedYY NN YN Stratified w/cat NY NN Compression Wave Y 4SY NN YN 2S w/tuned exhaustYY
44 Test Parameters To Be Measured Startability Multipositional 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
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)