This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
DETERMINATION OF TRUE ENGINE FRICTION
Annotation ability available
Sector:
Language:
English
Abstract
RELIABLE predictions of the improvements in efficiency that can be obtained by raising the compression ratio of spark-ignition engines are of obvious value in the long-range planning of both the automotive and petroleum industries.
New equipment and techniques were developed to measure indicated power by obtaining accurate pressure-volume measurements in each cylinder, thus permitting true friction to be determined as the difference between the indicated power of all cylinders and the simultaneously measured brake power. Tests were conducted on a 4-cylinder engine at compression ratios of 7/1 and 12/1.
Results demonstrate the inaccuracies of the conventional “motoring test” method of measuring friction, reveal the effect of changes in compression ratio on true friction, yield conclusive evidence that the potential gains in thermal efficiency from increased compression ratios are greater on both an indicated and brake basis than earlier studies indicated; and establish empirical thermodynamic relationships which provide a convenient and accurate means of predicting these potential gains in efficiency.
Recommended Content
Journal Article | Development of Fatigue Durability Analysis Techniques for Engine Piston using CAE |
Technical Paper | Oil Pressure Signatures for Engine Lubrication System Monitoring |
Technical Paper | Engine Piston Design - Art or Science? |
Authors
Citation
Gish, R., McCullough, J., Retzloff, J., and Mueller, H., "DETERMINATION OF TRUE ENGINE FRICTION," SAE Technical Paper 580063, 1958, https://doi.org/10.4271/580063.Also In
References
- Automobile Engineer Vol. 27 1937 57 58 “Degree of Error in Relation to Motor Testing,” McLeod. M. K.
- Erwin Wesley General Motors Research.
- “Internal-Combustion Engines,” Lichty. L. C. Sixth Edition 99 McGraw-Hill New York 1951
- SAE Transactions Vol. 63 1955 420 428 “Tractor Engine Design Requirements for Best Fuel Utilization,” Mueller H. T. and Gish. R. E.
- “Internal Combustion Engines,” Taylor C. F. and Taylor E. S. 47 by International Textbook Co. 1948