This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Intake Valve Throttling (IVT) - A Sonic Throttling Intake Valve Engine
Annotation ability available
Sector:
Event:
Mid-Year Meeting
Language:
English
Abstract
A spark ignition engine concept employing sonic throttling intake valves has demonstrated that the rapid, turbulent combustion process so produced permits extremely lean part-load operation. Light load mixture ratios in excess of 20:1 are possible without incurring the consequences of cyclic variations in cylinder pressure development and torque. A resulting improvement in fuel consumption is achieved.
The impetus for throttling the engine by means of the intake valves originated in the hypothesis that increasing the intensity of the small scale turbulence within the combustion chamber would effect an acceleration of combustion propagation rates during the initial period immediately after ignition. Throttling the engine by means of the intake valves results in sonic inflow velocity throughout the idle, road load, and acceleration operating ranges up to approximately two-thirds load. The mechanical means of operating engines on this principle have been demonstrated on both single and multicylinder engines. An extensive test program has established the operating characteristics of this method with respect to thermal efficiency and controllability. Preliminary vehicle tests have demonstrated stable operation at these lean mixture ratios.
Recommended Content
Authors
Topic
Citation
Stivender, D., "Intake Valve Throttling (IVT) - A Sonic Throttling Intake Valve Engine," SAE Technical Paper 680399, 1968, https://doi.org/10.4271/680399.Also In
References
- Patterson D. J. “Cylinder Pressure Variations, A Fundamental Combustion Problem.” SAE Transactions 75 1967 660129
- Clarke J. S. “Initiation and Some Controlling Parameters of Combustion in the Automobile Engine.” SAE Transactions 70 1962
- Willis D. A. Mayer W. E. Birnie C. Jr. “Mapping of Air Flow Patterns in Engines with Induction Swirl.” SAE Transactions 75 1967 660093
- Taylor C. F. Taylor E. S. “The Internal Combustion Engine.” Scranton, Pa. International Textbook Co. 1956
- Townsend A. A. “The Structure of Turbulent Shear Flow.” London Cambridge University Press 1956
- Spindt R. S. “Air-Fuel Ratios from Exhaust Gas Analysis.” SAE Transactions 74 1966 650507
- Hinze J. O. “Turbulence.” New York McGraw-Hill 1959
- Hottel H. C. Williams G. C. Levine R. S. “The Influence of Isotropic Turbulence on Flame Propagation.” Fourth Symposium (International) on Combustion Cambridge Mass. September 1952
- Schelkin K. I. Troshin Ya K. “Gasodinamika goreniya,” Izdatel'stvo Akademii Nauk SSSR Moscow 1963 “Gasdynamics of Combustion.” NASA TT F-231 October 1964
- Mickelsen W. R. Emstein N. E. “Propagation of a Free Flame in a Turbulent Gas Stream.” NACA Report No. 1286 1956
- Karlovitz V. Denniston D. Wells F. Journal of Chemical Physics 19 5 1951
- Bowditch F. W. “Some Effects of Turbulence on Combustion.” Fourth Symposium (International) on Combustion Cambridge, Mass. September 1952