Modeling Tools for Predicting the Impact of Modeling Tools for Predicting the Impact of Rolling Resistance on Energy Usage and Fuel Rolling Resistance on Energy Usage and Fuel
Efficiency for Realistic Driving CyclesEfficiency for Realistic Driving Cycles
CEC Workshop on Fuel Efficient Tires - 2002
Sacramento, CA
September 19, 2002
Kenneth J. KellySenior Engineer, Vehicle Systems Analysis Team
National Renewable Energy Laboratory
NREL MissionNREL Mission Lead the nation toward a sustainable energy future by Lead the nation toward a sustainable energy future by
developing renewable energy technologies, improving energy developing renewable energy technologies, improving energy efficiency, advancing related science and engineering, and efficiency, advancing related science and engineering, and facilitating commercializationfacilitating commercialization
Established in 1977 as Solar Energy Research Institute Established in 1977 as Solar Energy Research Institute (Achieved National Laboratory status in 1992)(Achieved National Laboratory status in 1992)
One of eleven DOE National LaboratoriesOne of eleven DOE National Laboratories
Current staff of approximately 1,000Current staff of approximately 1,000
Estimated operating budget of $200MEstimated operating budget of $200M
NREL BackgroundNREL Background
US Big 3 PartnershipUS Big 3 PartnershipHV program: 55 mpgHV program: 55 mpgPNGV: 80 mpg goal PNGV: 80 mpg goal
FreedomCARFreedomCAR
Vehicle Climate Control
Battery Thermal Management
Vehicle SystemsVehicle SystemsAnalysisAnalysis
Digital FunctionalDigital FunctionalVehicleVehicle
Advanced Vehicle Technologies Program
GMGMFordFordDaimlerChryslerDaimlerChrysler
Potential for Large Energy SavingsPotential for Large Energy Savings
Potential to Reduce Environmental ImpactsPotential to Reduce Environmental Impacts
Impact on the Existing Fleet of VehiclesImpact on the Existing Fleet of Vehicles
Cross-Platform ApplicationCross-Platform Application
Large and Important U.S. IndustryLarge and Important U.S. Industry
No Massive Infrastructure Changes RequiredNo Massive Infrastructure Changes Required
Potentially Low Incremental CostPotentially Low Incremental Cost
No Drastic Change in Consumer Behavior RequiredNo Drastic Change in Consumer Behavior Required
NREL’s Interest in Tires
Highway Energy Consumption GAP
2.7 mbpd2.7 mbpd
6.7 mbpd6.7 mbpd
Potential Energy Savings in the Transportation Sector
Total year 2005 savingsTotal year 2005 savings3.8 billion gal /year3.8 billion gal /year
Equivalent to replacing average car with: 15.7 MILLION Toyota Priuses
Introducing: NREL’s Advanced Vehicle Simulator
Introducing: NREL’s Advanced Vehicle Simulator
Available on the world wide web at:Available on the world wide web at:
(http://www.ctts.nrel.gov/analysis)
Three Main ADVISOR GUI Screens Vehicle InputVehicle Input
Simulation SetupSimulation Setup
ResultsResults
Basic Structure (database) How the Data/Models are Pulled into the GUI
BlockBlockDiagramDiagram
GUIGUI
Data FilesData Files
Basic Structure (models) In the Matlab/Simulink Environment
BlockBlockDiagramDiagram
LibrariesLibraries
BatteryBattery
EngineEngineControlControl
ADVISOR Setup Screen with Tire Menu
2cVbVaLPFR
New rolling resistance model in ADVISOR 2002 with J2452 test data supplied by Michelin
ADVISOR Rolling Resistance Block Diagram
2001 OE Fitments Size alpha beta a b c mass [kg] SMERF [N] SMERF P SMERF ZMercury Cougar P205/60R15 -0.4815 1.0051 6.82E-02 2.32E-04 1.20E-06 8.23 24.75 260 4051.5Kia Optima P205/60R15 -0.4745 0.9552 1.50E-01 4.87E-04 1.18E-06 9.51 35.98 260 4051.5Mazda 626 P205/60R15 -0.4243 0.9568 1.59E-01 3.44E-04 1.25E-06 10.55 48.63 260 4051.5
Volkswagen Eurovan P205/60R16 -0.4428 0.9036 2.11E-01 6.00E-04 2.17E-06 10.42 40.53 260 4223.1Honda Accord EX Coupe V6 P205/60R16 -0.3388 0.9375 1.01E-01 1.59E-04 9.93E-07 9.71 43.32 260 4223.1Dodge Stratus ES
Toyota Camry P205/65R15 -0.3937 0.8901 1.66E-01 3.50E-04 2.09E-06 9.71 37.41 260 4360.3Honda Accord LX & EX Sedan V6 P205/65R15 -0.3947 0.9468 1.13E-01 1.89E-04 2.24E-06 10.35 40.78 260 4360.3Hynudai XG300 P205/65R15 -0.3191 0.9076 1.23E-01 1.96E-04 1.52E-06 10.52 47.35 260 4360.3Lexus ES 300Nissan MaximaSaturn L Series
Subaru Outback P225/60R16 -0.4814 0.9463 1.47E-01 3.69E-04 2.38E-06 12.95 38.33 260 5012.7Ford Crown Victoria P225/60R16 -0.3881 0.9550 1.03E-01 1.46E-04 2.19E-06 11.08 47.21 260 5012.7Dodge Intrepid P225/60R16 -0.5888 1.0921 7.93E-02 1.18E-04 3.52E-07 15.29 55.69 260 5012.7Lincoln Town Car
Ford F150 P235/70R16 -0.4704 1.0129 8.49E-02 1.16E-04 2.64E-06 12.86 51.14 260 6180.3Mazda Tribute LX & ES P235/70R16 -0.4003 0.9315 1.39E-01 2.20E-04 1.90E-06 14.26 57.88 260 6180.3
P235/70R16 -0.4090 0.9765 1.06E-01 1.11E-04 1.52E-06 14.26 61.20 260 6180.3
Ford Explorer P235/75R15 -0.5007 0.9141 2.55E-01 4.69E-04 3.49E-06 13.30 54.08 260 6317.5Dodge Dakota P235/75R15 -0.4797 0.9464 2.08E-01 2.56E-04 3.94E-06 13.31 65.11 260 6317.5Chevy Trailblazer P235/75R15 -0.2601 0.8275 2.00E-01 2.50E-05 4.18E-06 13.80 71.30 260 6317.5Mercury MountaineerMitsubishi Montero Sport ES
Tire Sizes Currently in ADVISOR Database
ADVISOR Simulation Setup Screen with Drive Cycles
ADVISOR Results Screen
ADVISOR Results : Energy Use Figure
ADVISOR Simulation Results : Fr on the EPA’s Highway (HWFET) Cycle
ADVISOR Simulation Results : Fr on the EPA’s Urban (UDDS) Cycle
ADVISOR Simulation Results : Fr on the EPA’s Aggressive Driving (US06)Cycle
ADVISOR Simulation Results : Road-Load Energy and Fuel Economy
3.3%3.3%US06
5.9%5.9%HWFET
2.1%2.1%FTP
% change in FE% change in FE
Low RR vs med RR (30% lower Fr)Low RR vs med RR (30% lower Fr)
ADVISOR Simulation Results : Road-Load Energy and Fuel Economy
1.9%1.9%US06
3.4%3.4%HWFET
1.5%1.5%FTP
% change in FE% change in FE
Low RR vs med RR (19% lower Fr)Low RR vs med RR (19% lower Fr)
0
5
10
15
20
25
30
35
40
0 0.005 0.01 0.015 0.02 0.025
rolling resistance
Fue
l Eco
no
my (
mpg)
Car HWFET
Car City
SUV HWFET
SUV City
Parametric Sweep on rolling resistance showing the effect on fuel economy
ADVISOR is linked to optimization techniques and other tools in our Digital Functional Vehicle toolkit
OptimizationOptimizationToolsTools
ADVISOR
g(x)g(x)
ConstraintFunction
f(x)f(x)
ObjectiveFunction
Bringing it all together with Digital Functional Vehiclean integrated systems approach
NREL’s Energy-Smart Tire Vision
Adaptive Properties and Self
Regulating
• Energy Savings• Improved Performance• Improved Safety
Low Rolling Resistance
• Large Energy Savings
Long Life
• Reduced Solid Waste
• Reduced Particulate Pollution
• Energy Savings from Manufacturing and Materials
Conclusions and Additional Information
Potentially, Large Energy Savings Available from Energy Potentially, Large Energy Savings Available from Energy
Efficient TiresEfficient Tires
Government/Industry Partnership for More Detailed Analysis, Testing Government/Industry Partnership for More Detailed Analysis, Testing
and Directionand Direction
Tires Represent One of Only a Few Opportunities for Energy Savings Tires Represent One of Only a Few Opportunities for Energy Savings
in the Existing Fleet in the Existing Fleet
ADVISOR ModelADVISOR Model- Fast and Accurate Vehicle Systems ModelFast and Accurate Vehicle Systems Model- Free Free (http://www.ctts.nrel.gov/analysis)(http://www.ctts.nrel.gov/analysis)- Open Source CodeOpen Source Code- Vehicle, Component, Drive Cycle Library IncludedVehicle, Component, Drive Cycle Library Included- Conventional and Advanced Vehicle ConfigurationsConventional and Advanced Vehicle Configurations