This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
A New Method for Monitoring Thermal Energy Utilisation of Vehicle Engines
Annotation ability available
Sector:
Language:
English
Abstract
Proposals for a new method for measuring the fuel efficiency of engines in situ in vehicles are based on a new electronic instrument, the Ergometer, which measures the cumulative work energy delivered by an engine over a complex journey.
Engine thermal efficiency varies widely with load, speed, steady and transient operations. Measurement of EJATE, or Elapsed Journey Average Thermal Efficiency, derived from work and fuel measurements, gives clearer information on the state of development of a given vehicle's power train to meet economical driving conditions. Such information is considerably more revealing than conventional vehicle fuel consumption measurements.
The Ergometer can be fitted to individual vehicles, or to engine test beds. Most attractively it can be fitted to rolling road dynamometers where the EJATE of any vehicle can be easily measured.
The paper describes some EJATE test measurements undertaken for five journeys on one vehicle as well as the basic principle and construction of the *Ergometer work measuring instrument.
Authors
Citation
Merritt, D., Waide, M., and Nuttal, P., "A New Method for Monitoring Thermal Energy Utilisation of Vehicle Engines," SAE Technical Paper 931140, 1993, https://doi.org/10.4271/931140.Also In
References
- Leggett J Global Warming The Greenpeace Report 1990 Oxford University Press 0192177818
- Radermacher K The BMW Eta Engine Concept Proc. Inst. Mech. Engrs. 196 1982 95
- EPA Urban Dynamometer Driving Schedule for Light Duty Vehicles and Light Duty Trucks 40 1 July 1986
- Merritt D Dr