I M T Sloan Automotive Laboratory Massachusetts Institute
I M T Sloan Automotive Laboratory Massachusetts Institute of Technology Cambridge, MA, USA Sloan Automotive Laboratory 31-153 Massachusetts Institute of Technology 77 Massachusetts Avenue Cambridge, MA 02139-4307 Phone: (617) 253-4529 Fax: (617) 253-9453 http://engine.mit.edu December, 2004 I M T Sloan Automotive Laboratory Massachusetts Institute of Technology Cambridge, MA, USA Founded 1929 by Professor C.F. Taylor, with a grant from A. P. Sloan Established as a major laboratory for automotive research Extensive industrial and government funding Research areas: Internal combustion engine Fundamental combustion studies Engine/fuel interactions Engine and fuels technology assessment Objective: Contribute to future developments in automotive technology through fundamental and applied research on propulsion technology and fuels I
M T Sloan Automotive Laboratory Faculty and Staff Professor Wai K. Cheng, Associate Director Combustion, diagnostics, engine design Professor William H. Green, Jr. (Chem. Eng.) Combustion chemistry, fuels Professor John B. Heywood, Director Engine combustion, performance and emissions; engine design Professor James C. Keck (Emeritus) Combustion, thermodynamics, kinetics Dr. Tian Tian Analysis, lubrication, engine dynamics Dr. Victor W. Wong, Manager Lubrication, engine design and operating characteristics About 25 graduate students are involved in the research projects I M T Sloan Automotive Laboratory Facilities 12 Test Cells: Single cylinder Spark-Ignition engines Single cylinder HCCI engine with VVT Multi-cylinder Spark-Ignition engines Heavy Duty Multi-cylinder Diesel engine Optical-access engines with transparent cylinders for combustion and lubrication measurements Rapid compression machine I M
T Sloan Automotive Laboratory Facilities: Special Equipment LIF imaging systems Fluorescence-based lubricant film diagnostic High-speed digital video camera (1000 frames/s) Particulate Spectrometer Gas chromatograph Fourier transform infrared analyzer Laser Phase Doppler anemometer Fast-response FID Hydrocarbon and NOx analyzers I M T Current/Recent Research Projects Engine and Fuels Research Consortium (DaimlerChrysler, Delphi, Ford, GM, Saudi Aramco) Lubrication Consortium (Dana, Mahle, PSA, Renault, Volvo Truck) Homogeneous-Charge-Compression-Ignition (HCCI) Engine (DOE) Control-Auto-Ignition (CAI) Engine (Ford)
Plasmatron Enabled SI Engine Concepts (Ford, Arvin Meritor) Engine starting strategies (DaimlerChrysler) Robust Retarded Combustion (Nissan) Clean Diesel Fuels (DOE) Oil Aeration Study (Ford) Heavy Duty Natural Gas Engine Friction Reduction (DOE) Heavy Duty Diesel Engine Wear Reduction (DOD) High Speed Engine Lubrication (Ferrari) Assessment of Future Powertrain, Vehicle, and Fuels Technology (V. Kann Rasmussen Foundation, Energy Choices Consortium) I M T Industrial Consortium Operation
Multi-sponsor, multi-year program Pre-competitive research agenda Regular meetings (every 4 months) to set program agenda and discuss research findings Periodic visits to sponsor companies for discussion with staff Direct technology transfer through exchange of personal and use of facilities and computer codes I M T Engine and Fuels Research Consortium 1982 - present Current Focus: SI Engines Members: DaimlerChrysler Corp.,Delphi Corp., Ford Motor Co., General Motors Corp., Saudi Aramco Current Research Program Strategies to reduce engine start up emissions Fast catalyst light-off strategies Fundamental study of particulate matters formation Catalyst behavior: effects of sulfur and age on effectiveness I M T Industrial Consortium on Lubrication in IC Engines 1989 - present
Current Focus: Piston/liner tribology Members: Dana Corp., Mahle Corp., Peugeot SA, Renault, Volvo Truck Current Research Program Characterization of lubricant behavior between piston and liner and its impacts on engine wear, friction and lubricant requirements Quantitative 2D LIF visualization of oil film dynamics in the piston/liner interface Modeling of oil transport/consumption and ring friction Application to ring designs (geometry and tension) Research High Lights Drivers for Emissions Research 1975 1 1981 0.1 1994 US 1994 TLEV 1997 TLEV NOx (g/mile) NMOG (g/mile) 1 1975 1977 1977 1981 1994 TLEV 1997- 2003 ULEV
0.1 1997- 2003 ULEV 0.01 2004 SULEV2 2004 SULEV2 1975 1980 1985 1990 1995 2000 2005 2010 Starting year of implementation 0.01 1975 1980 1985 1990 1995 2000 2005 2010 Starting year of implementation Least square fit: Factor of 10 reduction in both HC and NOx every 15 years 1st peak Integrated HC emissions: 16 mg 2nd peak 55 mg Total: 71 mg (SULEV: FTP total is < 110 mg) Engine start up behavior 2.4 L, 4-cylinder engine Engine starts with Cyl#2 piston in mid stroke of compression Firing order 1-3-4-2 First fuel pulse ~90 mg/cylinder First firing: Cyl#2
First cycle in-cylinder results (SAE 2002-01-2805) First Cycle In-cylinder 4.5 R300 ( 40C, MAP 0.92 bar ) R600 ( 40C, MAP 0.8 bar ) 4 80C R900 ( 40C, MAP 0.7 bar ) R300 ( 60C, MAP 0.92 bar ) 3.5 R600 ( 60C, MAP 0.8 bar ) R900 ( 60C, MAP 0.7 bar ) 3 R300 ( 80C, MAP 0.92 bar ) 60C R600 ( 80C, MAP 0.8 bar ) R900 ( 80C, MAP 0.7bar ) 2.5 R200 ( 20C, Zetec Engine ) R200 ( 0C, Zetec Engine ) 2 40C 1.5 RPM Tcoolant 20C
1 0.5 0C 0 0 50 100 Lean Limit of consistent firing 150 200 250 Injected Fuel Mass (mg) 300 350 First cycle fuel delivery efficiency results (SAE 2002-01-2805) R300 ( 40C, MAP 0.92 bar ) R600 ( 40C, MAP 0.8 bar ) R900 ( 40C, MAP 0.7 bar ) 1 R300 ( 60C, MAP 0.92 bar ) Delivery Efficiency f 0.9 R600 ( 60C, MAP 0.8 bar ) 80C R900 ( 60C, MAP 0.7 bar )
200 250 300 Effect of delaying IVO on 1st cycle fuel delivery INCOMING MIXTURE INCREASINGLY LEAN AS PISTON DRAWS IN CHARGE 1.2 1.1 1.0 INTAKE FLOW LEAN 0.9 0.8 RICH 0.7 0.6 0.5 -20 -10 0 10 20 Intake Valve Opening (CAD from TDC Exhaust) Injected mass: PISTON DISPLACES MORE LEAN
CHARGE AS IVC DELAYED PISTON 132.9 mg 199.3 mg 265.7 mg Pressure(bar) or HC mole fraction (%) Fuel equivalence Ratio ( ) (SAE 2004-01-1852) 35 HC 30 25 20 15 Pressure In-cylinder HC value for calculation 10 5 0 0 500 1000 Crank angle
1500 2000 Exhaust port/runner oxidation with retard spark timing 60 HC Emissions (g-HC/kg-fuel) 50 40 Cylinder Exit [Quenching] Port Exit [FFID: 7-cm from EV Runner [FFID: 37-cm from EV Exhaust Tank 120-cm from EV 30 20 10 0 15 0 -15 Spark Timing ( BTDC) 3.0 bar n-imep, 1500 RPM, = 1.0, 20C Secondary air injection 3.0 bar NIMEP, 1500 RPM, 20 C 1.4 HC/HCref 1.2
exhaust = 0.85 Sp = 15 BTDC 1.0 0.8 0.6 = 0.85 = 1.0 = 1.1 0.4 0.2 0.5 Sp = -15BTDC Sp = 0 BTDC 1.0 1.5 Exhaust=1.4 2.0 2.5 hs )catalyst (m Re f. value 3.0 3.5 4.0 Ref value: at condition of 15oBTDC spark and = 1
1 NO/NO inlet 0.8 Catalyst performance 4K miles aged 50K miles aged 0.6 150K miles aged 0.4 (SAE 2003-01-1874) 0.2 0 CO/CO inlet 1 0.8 4K miles aged 50K miles aged 150K miles aged 0.6 7 ppm fuel S 1600 rpm 0.5 bar Pintake Space vel. - 4.4x104/hr modulation - 2 Hz - = 0.025 0.4
0.2 0 HC/HC inlet 1 4K miles aged 0.8 50K miles aged 0.6 150K miles aged 0.4 0.2 0 0 0.2 0.4 0.6 0.8 Fraction of cumulative catalyst volume 1 Time-resolved NO profiles along catalyst (SAE 2003-01-1874) Aged 4k-miles; 4.4x104/hr space vel.; l modulation: 1Hz, = 0.03 500 0% cumulative catalyst vol. NO (ppm) 250
Time (s) 6 8 10 2 1 O storage capacity (g) 2 Normalized O2 Storage Fuel Sulfur Effect on Oxygen Storage Capacity: Age effect and fuel S effect are separable 1 Slope: 0.8 10% decrease 0.6 0 in O2 storage capacity with every 150 ppm increase in fuel S 100 200 300 400 Fuel sulfur (ppm)
500 7ppmS 33ppmS 266ppmS 500ppmS Power law: O2 storage age- 0.84 10 100 Catalyst age (k-miles) Plasmatron Fuel Reformer Developed at the MIT Plasma Science and Fusion Center Ideal Partial Oxidation Reaction: Cn H m n m n plasmatron O2 3.773N 2 nCO H 2 3.773N 2 2 2 2 Fuel Air 1 1 Plasmatron Products of the Ideal Reaction Species Mole Fraction 1st Stage 2 Reactor
Air 2 Nozzle 3 Section Fuel Air 3 24nd Stage Reactor Flow Direction H2 25% CO 26% N2 49% Effect of Plasmatron gas on lean operation (1500 rpm, 3.5 bar NIMEP, SAE2003-01-0630) Overall Net Indicated Efficiency (%) 33% 32% Synth. Plas. gas = 10% 31% Synth. Plas. gas = 20% 30% Synth. Plas. gas = 30%
1 0 56 NIMEP SI cycles with late IVC and late EVC 58 First HCCI cycle(60); early IVC Last SI cycle(59); early EVC 60 62 64 Cycle number 66 68 70 Relationship between IMEP and CA-50 5 4.5 4 IMEP(bar) 3.5
3 2.5 2 Gross Net Pumping 1.5 1 0.5 0 10 12 14 16 10 20 22 24 CA-50 location (o after TDC compression) 26 28 Nimep (bar) EVC (ATDC-i) IVC (ATDC-i) Valve timing scheduling in mode transition IVC closer to BDC, increase of compression and trapped charge mass
5 0 Nimep (bar) SI/HCCI/SI Transitions SI HCCI SI Cycle# Start with SI mode Transition into CAI mode in cycle# 60 Transition back to SI mode in cycle# 136 Transition into CAI mode in cycle# 177 HCCI Open loop control: Modulation period at 30 cycles 1500 rpm; modulation period of 30 cycles=2.4 sec IMEP(bar),fuel mass per cycle(mg) 6 GIMEP 5 4 3 2 Fuel mass x 10 NIMEP 1 0 -1 0
PMEP 50 100 150 200 Cycle no. 250 300 Open loop control: Modulation period at 14 cycles 1500 rpm; modulation period of 14 cycles=1.12 sec IMEP(bar),fuel mass per cycle(mg) 6 GIMEP 5 4 3 2 Fuel mass x 10 NIMEP 1 0 PMEP -1 0 50 100 150 200
4 120 3.5 110 3 T RPM RPM 1.1 1700 1600 1 100 2.5 2 0 0.9 100 200 300 400 500 600 700 800 900 1000 Engine Cycle 1500 1400 1300 LIF Oil Distribution Image No load (1 N.m) - Coolant 50 C - Oil 50 C Expansion stroke 7 mm 20 mm Fluorescence intensity profile
Ring Pack Geometry crown land skirt Top Ring Up-Scraping Effect (1) 1700 rpm - No load (1 N.m), Coolant 50 C - Oil 50 C Compression stroke Late compression stroke Ring Twist + Piston Tilt Anti-Thrust Side Transport on the land: INERTIA INERTIA Early Upward Stroke Exhaust & Compression Stroke Exhaust stroke INERTIA Compression stroke 1200 rpm - No load (1 N.m) - Coolant 50 C - Oil 50 C Transport on the land in CIRCUMFERENTIAL DIRECTION 1200 rpm - No load (1 N.m) - Coolant 50 C - Oil 50 C Compression stroke t=0s 3 mm
t=1s (10 cycles) t=2s (20 cycles) 6 mm Circumferential Oil Flow Oil Transport through the Ring Gaps and Mist generation Top Ring Scraper Ring Break up into mist by high velocity gas flow (liquid entrainment) Liquid oil Ring Land 1 PCV 3. gas ~ 2 Qoil Qgas h oil 2 h gas . oil Ring Land 2 Width of the gas flow B. Thirouard Oil dragged from the piston may be entrained into mist. Oil mist is carried by gas flow going to crankcase or back to the combustion Chamber.
Ring Pack simulation code structure GAS FLOW and RING DYNAMICS PISTON SECONDARY MOTION RING - LINER LUBRICATION OIL TRANSPORT and OIL CONSUMPTION Ring/Groove Interface Gas Flows asperity contact Major Elements of the Existing Ring Pack Models RING oil Through gaps Through groove GROOVE area in direct asperity contact oil squeezing pgas oil  Rail/Expander Interaction Forces and pressures from the Expander/Spacer
CG  Ring/Liner Interface Mixed Lubrication Three Lubrication Modes Outlet conditions Flow continuity Through waviness Through bore Dynamics of the Rings Oil Consumption Analysis Package Fundamental Models RINGPACK-OC FRICTION-OFT TLOCR TPOCR PISTON2nd Individual Oil Transport Processes and models Zone Analysis Ring/Liner Scraping Redistribution Ring/groove Pumping out Gas flow dragging Piston lands Gas flow driven Inertia driven Vaporization
On liner On piston Gap Gap position Mist Research highlights: Integration of modeling and the Experiments on production and single-cylinder engines Transient oil consumption and Mechanism Modeling Measurements from the Production Engine 1000 4200 rpm; 0 % - WOT 900 60 Blow-By [l/min], Air Flow[l/s] 800 Oil Cons. 700 Blow-By 600 Air flow 400 300 10 40 500
Recent clinical trials that served as a basis for the approval of two new medications for IPF differed regarding their inclusion criteria. The ASCEND study enrolled patients without a surgical biopsy only if they showed a definite UIP pattern on...
"Shand tucthiney m?" le ollds mind Theybooure He, he s whit Pereg lenigabo Jodind alllld ashanthe ainofevids tre lin--p asto oun Let s be the previously produced character. The probability that c is the next character to be produced equals...
Chapter 1 Introduction: Themes in the Study of Life ... Replacing bulb will fix problem Test of prediction Test of prediction Test falsifies hypothesis Test does not falsify hypothesis Prediction: Replacing batteries will fix problem Forming and Testing Hypotheses Observations...
Grade 8 Classroom Video Debrief Discuss observations from the video Role play how you, as the coach, would debrief with this teacher. Grade 9 Classroom Video Materials DI- Professional Learning Series Insert pic of session outline for day on Questioning...
The Law of Conservation of Mass: The total mass of the reactants must equal the total mass of the products Total mass of reactants = Total mass of products ... H2, N2, F2, Cl2, Br2, I2 and O2 (Remember "HOFBrINCl")...
Spine. Leaf. TCP/IP. Receiver masks packet reordering due to . multipathing. below transport layer. Sender breaks data into . flowcells. Set up multiple paths. This kind of fine-grained load balancing scheme can cause packet reordering at the receiver side, therefore,...