Powertrain Selection for Fuel Economy and Acceleration Performance

Developing vehicles that achieve optimum fuel economy and acceleration performance is critical to the success of any automotive company, yet many practicing engineers have not received formal training on the broad range of factors which influence vehicle performance. This seminar provides this fundamental understanding through the development of mathematical models that describe the relevant physics and through the hands-on application of automotive test equipment. Attendees will also be introduced to software used to predict vehicle performance.

The course begins with a discussion of the road load forces that act on the automobile (aerodynamic, rolling resistance, and gravitational) followed by a review of pertinent engine characteristics. This background information is then used to show how appropriate gear ratios for a vehicle transmission are selected and to develop models for predicting acceleration performance and fuel economy. The models form the basis for the computer software used to predict vehicle performance. Participants will also use an in-vehicle accelerometer, GPS fifth-wheel, and an OBDII scanner to measure vehicle performance.

What Will You Learn

By attending this seminar, you will be able to:
  • Explain the basic operation of the components in an automotive powertrain
  • Calculate road loads on a motor vehicle
  • Select appropriate gear ratios for a given engine/chassis combination
  • Predict the effect of gear selection, body design, and weight on the fuel economy of a vehicle
  • Explain and utilize the mathematical models for predicting the acceleration of an automobile
  • Explain and utilize the mathematical models for predicting the fuel economy of an automobile
  • Use computer software for predicting vehicle fuel economy and performance

Is This Course For You

As this seminar is designed for automotive engineers involved in the design and development of automotive powertrains (with special value for entry-level engineers and others seeking to develop a fundamental understanding), attendees should have a degree in mechanical engineering or a related field, be able to apply Newton's second law of motion, and be familiar with spreadsheets and simple computer programming concepts.

Materials Provided

This data is not available at this time

Course Requirements

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  • Course Introduction/Powertrain Configuration
    • Powertrain layout: front-wheel drive, rear-wheel drive, four-wheel drive
    • Powertrain components: engine, clutch/torque converter, transmission, drive shaft, differential, tires
  • Road Load Forces and Power
    • Vehicle freebody diagram
    • Aerodynamic forces
    • Rolling resistance forces
    • Gravity forces
  • Vehicle Coastdown Test
    • Theory behind coastdown test
    • GPS fifth-wheel
    • SAE Recommended Practice J1263
  • Vehicle Tractive Effort
    • Characterization of internal combustion engines
    • Characterization of pneumatic tires
  • Drivetrain Selection
    • Vehicle design criteria
    • Selection of top gear ratio
    • Selection of low gear ratio
    • Selection of intermediate gear ratios
  • Analysis of Power and Torque Flow in Drivetrain Components
    • Clutches
    • Standard & planetary gear sets
    • Axles and differentials
    • Manual transmissions
    • Automatic transmissions
    • Torque Converters
  • Acceleration Performance Prediction
    • Vehicle acceleration modeling
    • Effects of drivetrain component selection
  • Road Load and Acceleration Power Testing Laboratory
    • In-vehicle accelerometer
    • GPS fifth-wheel
    • SAE Recommended Practice J1491
  • Fuel Economy Prediction
    • Vehicle fuel economy modeling
    • EPA driving cycles
    • CAFE standards
    • Effects of drivetrain component selection
    • SAE recommended practice J1256
    • Emissions prediction
  • Demonstration of Vehicle Performance Software
    • DOE Advisor
    • Commercial packages
    • Effects of drivetrain component selection