overview of ornl’s combustion portfolio relevant to fluid ... · ornl is managed by ut -battelle,...
TRANSCRIPT
ORNL is managed by UT-Battelle, LLC for the US Department of Energy
Overview of ORNL’s Combustion Portfolio Relevant to Fluid PowerJim Szybist*
October 24, 2019
CCEFP Summit, University of Wisconsin
*Presenting for the numerous staff member at ORNL whose work is included in this presentation
22
Acknowledgements• DOE Vehicle Technologies Office• DOE Bioenergy Technologies Office• Fuels, Engines, Emissions Research Center (FEERC) colleagues
– Jun Qu, Mike Kass, Brian Kaul, Eric Nafziger, Derek Splitter, Brian West, Robert Wagner, and more…
33
Main Campus and Spallation Neutron Source (inset)
44
ORNL is DOE’s largest multi-program science and energy lab
3,200researchguests
annually
Nation’s largest
materials research portfolio
$1.8B budget
Nation’s most diverse
energy portfolio
Forefrontscientific
computing facilities
World-class
research reactor
$750M modernization
investment
4,750employees
World’s most intense
neutronsource Managing
major DOE projects: US ITER, exascale
computing
2,203journal articles
published in CY15 185
inventiondisclosures
in FY16
83patents issuedin FY16
55
ORNL Sustainable Transportation Program (STP)Pursuing a diversity of technologies to reduce environmental impact while establishing predictable, reliable, and secure personal mobility and freight movement
ACCELERATING ELECTRIFICATION• Wireless power transfer• Advanced power electronics and
electric motors• Next generation battery materials
and manufacturing• Fuel cells
IMPROVING VEHICLE EFFICIENCY• Advanced engine and emissions
controls• Hybrid powertrains and vehicle
systems integration• Lightweight and propulsion
materials• Advanced lubricants
DEVELOPING SUSTAINABLE FUELS• Co-development of fuel and engine
technologies• Alternative fuel GHG analysis• Critical data for the introduction of
new fuels
ENABLING INTELLIGENT SYSTEMS AND OPERATIONS• Predictive data for decision making• Data sciences and cyber security• fueleconomy.gov• Congestion management• Efficient operation of commercial vehicles
REVOLUTIONIZING MANUFACTURING• Additive manufacturing for
components to full vehicles• More efficient processes
66
Examples of significant ORNL contributions to transportation
Material Science & Technology• CF8C-plus steel, Al alloys, and ceramics used in
millions of engines• Leading development of affordable carbon fiber• Diagnostics in support of emissions controls
Data, Analysis, Modeling• NAS and congressional testimony
• Transportation Energy Databook
• Freight analysis framework (DOT)
• “Billion Ton” biomass study
• Logistics modeling (DOD)
• FuelEconomy.gov
Fuel Supply and Emissions Certification
• Data cited in EPA 15 ppm sulfur diesel fuel rule
• Data cited by EPA in 15% ethanol waiver decision
• NMOG correlation codified in CARB LEV III and EPA Tier 3 rule
Vehicle Propulsion Systems• Innovative emissions diagnostics enables clean
diesel engine
• 15+ years of high efficiency combustion research
• Go-to laboratory for demonstrating DOE program engine efficiency goals
• Development and benchmarking of HEV components
77
Laboratory Capabilities Relevant to Fluid Power
• Lubricants (Jun Qu)• Combustion• Alternative Fuels
88
Laboratory Capabilities Relevant to Fluid Power
• Lubricants (Jun Qu)• Combustion• Alternative Fuels
99
Background: Environmentally friendly lubricants desired for hydropower and hydraulics
• EPA-approved base oils of Environmentally Acceptable Lubricants (EALs) include – Water-based (only for limited light-duty components) and – Oil-based, e.g., vegetable oils, synthetic esters, polyalkylene glycols (PAGs).
• Lack of eco-friendly, effective anti-wear (AW) additives– Conventional AW and EP additives, such as ZDDPs, are not allowed in EALs due to
their toxicity. – Traditional ashless (metal-free) additives, such as TPPT, have lower toxicity but their
wear protection is somewhat inferior.
ZDDP TPPT
The idea: developing eco-friendly ionic liquids as novel anti-wear and friction-reducing additives.
1010
Background: Ionic liquids for lubrication
Ionic liquids (ILs) are ‘room temperature molten salts’, composed of cations & anions, instead of
neutral molecules.
NR
N NR
+ N++
R1
R2 R3
R4 P
+R1
R2 R3
R4
Tetraalkyl-ammonium
Tetraalkyl-phosphonium
1-alkyl-3-methyl-imidazolium
N-alkyl-pyridinium
1
2
3
4 5
(R1,2,3,4 = alkyl)
NR
N NR
+ N++
R1
R2 R3
R4 P
+R1
R2 R3
R4
Tetraalkyl-ammonium
Tetraalkyl-phosphonium
1-alkyl-3-methyl-imidazolium
N-alkyl-pyridinium
1
2
3
4 5
(R1,2,3,4 = alkyl)
[PF6]- [BF4]-
[CF3CO2]-, [NO3]-[CH3CO2]-
[BR1R2R3R4]-
[CF3SO3]-[(CF3SO2)2N]-
Br-, Cl-, I-
[Al2Cl7]-, [AlCl4]-[(C2F5SO2)2N]- (BETI)
(Tf2N)[PF6]- [BF4]-
[CF3CO2]-, [NO3]-[CH3CO2]-
[BR1R2R3R4]-
[CF3SO3]-[(CF3SO2)2N]-
Br-, Cl-, I-
[Al2Cl7]-, [AlCl4]-[(C2F5SO2)2N]-[(C2F5SO2)2N]- (BETI)
(Tf2N)
[P(O)2(OR)2]− (phosphate)[P(O)2(R)2]− (phosphinate)
Common Cations
Common Anions
• ILs as neat lubricants or base stocks– High thermal stability (up to 500 oC)– High viscosity index (120-370)– Low EHL friction w/ low pressure-viscosity coefficient– Wear protection by tribo-film formation– Technical problem: Many earlier ILs corrosive
• ORNL developed the 1st group of non-corrosive ILs in 2006 (U.S. patent #7,754,664)
• ILs as oil additives for engine/gear lubrication– Potential multi-functions: AW/EP, FM, etc.– Ashless low sludge– Allow the use of lower viscosity oils– Advantage: cost effective and easier market penetration– Technical problem: most ILs insoluble in oils (<<1%)
• ORNL invented 1st group of oil-soluble ILs in 2010 (U.S. patent #9,957,460, 2014 R&D 100 Award)
• ILs as eco-friendly lubricant additives for hydropower/hydraulics
– Problem: many ILs as toxic as traditional ZDDP• ORNL invented the 1st group of eco-friendly ILs in
2019 (ORNL Invention Disclosure)
1111
ORNL’s Eco-Friendly, Anti-Friction/Wear Ionic Liquids for Hydropower/Hydraulic LubricationBackground: Environmentally Acceptable Lubricants (EALs) are highly desired, but conventional additives are either toxic or ineffective.
Approach: Develop eco-friendly ionic liquids as EAL additives• Good solubility in EALs• Superior lubricating
performance• Low or no toxicity in aquatic
environments: o EPA chronic toxicity test
using Ceriodaphnia dubia
Technical contact: Jun Qu (865-576-9304, [email protected])
Test lubricants: PAG (Polyalkylene glycol) PAG+ 5% additive
(ZDDP or IL)Diluted to 10 ppm in water
(0.5 ppm ZDDP or IL)
PAG OSP Mineral0
1
2
3
4
5
Wea
r Vol
ume
(105 µ
m3 )
No additive+ 0.5% ZDDP+ 0.5% IL-1
Tribology
Neat PAG+ ZDDP+ IL-1
Toxicity
Survival rate Reproduction rate
0 0 0 0 0 0
1616
Laboratory Capabilities Relevant to Fluid Power
• Lubricants• Combustion• Alternative Fuels
1717
Primarily Automotive Focused, but Wide Range of Engine Sizes and Combustion Approaches• Eight engine dynamometer laboratories at ORNL
– Most with double-ended dynamometers– Includes single and multi-cylinder engines
• Research includes spark ignition, compression ignition, and numerous advanced compression ignition strategies
• Research includes a variety of engine sizes– Engines for unmanned aerial vehicles (UAVs), < 100 cc/cylinder– Automotive SI engines, 400-600 cc/cylinder– MD and HD diesel engines, up to 2,500 cc/cylinder– Scaled-down version of marine diesel engine, 4,000 cc/cylinder
• Extensive fuels research– Co-Optima initiative to co-develop biofuels and new combustion strategies– Liquid and gaseous fuels research (natural gas and propane)
• Extensive emission controls research
EGR
Plenum
Intake
Exhaust
Plenum
1818
Exxon-Mobil is Funding Lubricant Research on Custom 1/10 Scale Engine for Marine Diesel
In part, lubricant research is motivated in fuel uncertainty for marine industry…
1919
The engines used to power these vessels are equally large. Two noteworthy features are their high efficiencies (50%) and that they are directly coupled to the propeller.
Configuration Turbocharged crosshead 2-stroke inline diesel, 6 to 14 cylinders
Bore 0.96m (3.14 ft)Stroke 2.5m (8.4 ft)Speed 22 – 102 RPMBMEP 1.96MPa @ full loadPower 5720 kW/cylinderFuel consumption 160 g per cylinder per cycle
(up to 250 tons/day)Crankshaft weight
300 tons (14 cylinder version)
Piston weight 5.5 tons
Wärtsilä RT-flex96C
20
*BP (British Petroleum). 2018. BP Statistical Review of World Energy, 67th Edition.**DNV GL. 2018. “Current Price Development Oil and Gas.” Accessed December 2018. https://www.dnvgl.com/maritime/lng/current-
price-development-oil-and-gas.html.
Large marine vessels are fueled using a range of distillate and residual fuels for use in diesel-type engines.
Marine fuel typeEstimated quantity consumed (million
tonnes/year)*
Estimated cost**
($$/metric ton) ($$/gallon)HFO (residual fuel) 230 460 1.72MGO (distillate fuel) 10 700 2.62MDO (MGO/HFO blend) 65 ~700 ~2.62
Residual Fuel Oils Distillate FuelsHigh sulfur/asphaltene content contributes to high BC and SOxemissions
Lower sulfur content, produce significantly lower high BC and SOxemissions than HFO
High viscosity requires heat energy to achieve proper flow characteristics Does not require additional heat
High levels of ash, cat fines, and water require onboard processing and storage No waste generation
Highly variable chemistry may cause incompatibilities and stratification
More consistent fuel chemistry
Deep sea use Higher cost precludes deep sea use
This Photoby Unknow
n Author is licensed under C
C BY-SA
Ships typically hold between 15,000 and 18,000 containers. Each container is roughly the size of a tractor trailer rig.
2121
Sulfur emissions from marine vessels are being regulated globally and in coastal zones known as Emission Control Areas (ECAs)
This Photo by Unknow
n Author is licensed under CC
BY-NC
Sulfur reductions are being met by:• Reducing sulfur content of HFO• Switching to low sulfur fuel
when operating in ECAs• Emission control technologies
Key regulatory agencies are:• The International Maritime Organization (IMO)• US EPA• California Air Resources Board (CARB)Sulfur is regulated by regulating the fuel sulfur content and not emissions as is typically done
Perc
ent s
ulfu
r in
fuel
22
IMO 2020 Sulfur cap will mandate the development of new marine lubricants to cope with changes to fuel lubricity and slow speed operation.
• HFO contains up to 3.5% sulfur and requires heating to flow.
• In order to comply with the low sulfur ruling, some fuel suppliers are expected to blend in higher levels of distillates.
• 40,000 ships burn 250-300 tonnes of fuel/day – Same order of magnitude as US on-road diesel consumption– This global increase in diesel demand will potentially raise the cost of diesel fuel.
• However, many refineries state that they can meet the low sulfur specifications through additional processing of crude.
• Lots of unknowns at the moment.
2323
Laboratory Capabilities Relevant to Fluid Power
• Lubricants• Combustion• Alternative Fuels
2424
Additionally, Emissions Regulations for Nonroad Diesel Engines May Become More Stringent in Future• Historically nonroad diesel engine emission regulations have lagged highway regulations
– Highway engines reduced NOx emissions to 0.2 g/bhp-h in 2007– Proposed California rule will reduce that to 0.02 g/bhp-h in future
• Non-road engines > 56 kW– NOx Currently at 0.4 g/kW-h (0.3 g/bhp-h)– Further reductions increases need for lean NOx emission controls
• Alternatives to diesel engines for on-highway to meet NO– Cummins producing 12 L, 400 hp engine using natural gas– Stoichiometric fueling allows the use of a 3-way catalyst– Peak efficiency of some SI engine now exceeds 40%
• Propane and natural gas are both alternatives with substantial price benefits and simplify emissions controls
– Stoichiometric combustion with 3-way catalyst
*screenshot from www.cngnow.com on 10/21/19
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
1970 1980 1990 2000 2010 2020
2018
$/ D
iese
l Gal
lon
Equi
vale
nt
Diesel Price (2018 $/DGE)
Propane Price (2018 $/DGE)
*Data from the Transportation Energy Data Book**Reflects refinery sale price, does not include
transportation and sales tax
2525
High Efficiency SI Research Using is a Strength of ORNL Combustion Program• Pressure-Temperature (PT) Autoignition Framework
– Bringing kinetics to applied understanding
• Fuel/lubricant interactions on LSPI propensity
• Custom long-stroke engine for high efficiency
• Fuel reforming for thermochemical recuperation and EGR limit extension
26
Octane Index (OI) Allows Fuel Quality Expectations to be Set for both SI and ACI Combustion Strategies
• Relative ranking of fuels change with operating condition– Research octane number (RON) and motor octane number (MON) are
different because they represent different engine conditions
• OI, pioneered by Kalghatgi, uses a variable K to account for changing operating conditions (SAE 2001-01-3584, 2005-01-0239)
– OI = RON – K*(RON – MON)
RON MON
Fuel 1 98 98
Fuel 2 95 85
Fuel 3 93 87
Fuel 4 97 91
Fuel 5 92 82
Which Fuel is Best? It Depends.
Fuel Ranking
RON Condition
s
MON Conditions AKI K = -0.5 K = -1 K = -2
Best Fuel 1 Fuel 1 Fuel 1 Fuel 2 Fuel 2 Fuel 2
Fuel 4 Fuel 4 Fuel 4 Fuel 4 Fuel 4 Fuel 5
Fuel 2 Fuel 3 Fuel 2 Fuel 1 Fuel 5 Fuel 4
Fuel 3 Fuel 2 Fuel 3 Fuel 5 Fuel 3 Fuel 3
Worst Fuel 5 Fuel 5 Fuel 5 Fuel 3 Fuel 1 Fuel 1
ACI Ranking K = 2
Least Reactive Fuel 1
Fuel 4
Fuel 3
Fuel 2
Most Reactive Fuel 5
High Reactivity Allows ACI to be Achieved More
Readily
27
300 400 500 600 700 800 900 10000
10
20
30
40
50
Beyond RON
Beyond MON
Pin = 0.5 bar Pin = 0.75 bar Pin = 1.0 bar Pin = 1.25 bar Pin = 1.5 bar Pin = 2.0 bar
Pres
sure
[ ba
r ]
Temperature [ K ]300 400 500 600 700 800 900 10000
10
20
30
40
50
Beyond MON
Pres
sure
[ ba
r ]
Temperature [ K ]
Pin = 0.5 bar Pin = 0.75 bar Pin = 1.0 bar Pin = 1.25 bar Pin = 1.5 bar Pin = 2.0 bar HCCI Trace
300 400 500 600 700 800 900 10000
10
20
30
40
50
Beyond MON
Pres
sure
[ ba
r ]
Temperature [ K ]
Pin = 0.5 bar Pin = 0.75 bar Pin = 1.0 bar Pin = 1.25 bar Pin = 1.5 bar Pin = 2.0 bar HCCI Trace
98 RON, 12 S
300 400 500 600 700 800 900 10000
10
20
30
40
50
Beyond RON
Beyond MON
Pres
sure
[ ba
r ]
Temperature [ K ]
Pin = 0.5 bar Pin = 0.75 bar Pin = 1.0 bar Pin = 1.25 bar Pin = 1.5 bar Pin = 2.0 bar HCCI Trace
98 RON, 1 S
1000 2000 3000 4000 5000200
400
600
800
1000
1200
1400
1600
1800
2000
BMEP
[ kP
a ]
Speed [ RPM ]
15
18
21
24
27
30
33
36
39
Brake Efficiency [%]
1000 2000 3000 4000 5000200
400
600
800
1000
1200
1400
1600
1800
2000
BMEP
[ kP
a ]
Speed [ RPM ]
15
18
21
24
27
30
33
36
39
Brake Efficiency [%]
Operating Condition Determines Pressure-Temperature Trajectory, Dictating Autoignition Kinetics
27
28
600 700 800 900 10000
10
20
30
40
50Beyond RON
Beyond MON
Pres
sure
[ ba
r ]
Temperature [ K ]
RON 98, S = 1 RON 98, S = 11
Comparing Constant Ignition Delay for Different Fuels Enable a Better Understanding of RON, MON, and OI
For Naturally Aspirated Engine at WOT, Fuels
are Similar
Under boost, High S fuel is
Better
8ms ID Contours
Under MON Conditions, Low S fuel is Better
Beyond MON Conditions – Unclear
Which Fuel More Reactive
2929
Long-Stroke Engine Geometry shows path to high BTE, λ=1
• Honda high S/B ratio research engine (SAE 2015-01-1263)– Enabled high EGR without detrimental effect on combustion duration– High rc used (~17:1 geometric, ~12.4:1 effective) miller cycle
• Can become air/mivc limited at increased loads– 91 RON pump gasoline used with high boost (trapped mass)
3030
Actual Design “Combines” Two Engines• Rod/block pinch issue
– Compromise was reduce rod/stroke ratio
• Cylinder head from LNF – Surman “camless” valve system– Late IVC possible
• Block is billet Aluminum– Short block modeled after drag
racing engine
• Crank and rod are custom billet steel (300M)
• Internally balanced – First order balance from opposite bob
weight
3131
Engine Uses Sturman Valves with Custom Block
3232
Using Propane as Fuel, Very Fast Combustion and Projected BTE = 40% for Stoichiometric SI
• GTE > 46% and conservative correlations used to project 40% BTE
• High S/B configuration significantly reduces combustion duration because of high turbulence
4 6 8 10 12 14 16 18 20 2236384042444648 30
323436384042444626
2830323436384042
propane 9.2:1=rc, S/B=1 propane, 13.3:1=rc, S/B=1 propane, 13.3:1=rc, S/B=1.5 propane, 16.8:1=rc, S/B=1.5 propane, 16.8:1=rc, S/B=1.5, LIVC + EGR
η gr
oss
(%)
IMEPg (bar)
η ne
t (%
)
η br
ake
(%)
4 6 8 10 12 14 16 18 20 225
10
15
20
25 94
96
98
10012
16
20
24
28
propane 9.2:1=rc, S/B=1 propane, 13.3:1=rc, S/B=1 propane, 13.3:1=rc, S/B=1.5 propane, 16.8:1=rc, S/B=1.5
CA50
(°CA
)
IMEPg (bar)
η co
mbu
sito
n ( %
)
CA2
- CA
85 (°
CA)
3333
Summary• ORNL has a diverse range of expertise that can be applied to s
science and engineering challenges, included fluid power• Developing a next-generation ionic lubricants that provide
superior performance and are environmentally acceptable• Wide range of experience and expertise with engines,
combustion strategies, and alternative fuels– Facilities cover a wide size range of engines and combustion type– Marine fuel change may increase demand and cost of diesel fuel in
the near future– ORNL capabilities can help design and identify high efficiency
operation with alternative fuels