NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Turbulent flame propagation and combustion in spark ignition enginesPressure measurements synchronized with high-speed motion-picture records of flame propagation have been made in a transparent-piston engine. The data show that the initial expansion speed of the flame front is close to that of a laminar flame. As the flame expands, its speed rapidly accelerates to a quasi-steady value comparable with that of the turbulent velocity fluctuations in the unburned gas. During the quasi-steady propagation phase, a significant fraction of the gas behind the visible front is unburned. Final burnout of the charge may be approximated by an exponential decay in time. The data have been analyzed in a model-independent way to obtain a set of empirical equations for calculating mass burning rates in spark-ignition engines. The burning equations contain three parameters: the laminar burning speed, a characteristic speed (uT), and a characteristic length (lT). The laminar burning speed is known from laboratory measurements. Tentative correlations relating uT and lT to engine geometry and operating variables have been derived from the engine data.
Document ID
19830066938
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Beretta, G. P.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Rashidi, M.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Keck, J. C.
(MIT Cambridge, MA, United States)
Date Acquired
August 11, 2013
Publication Date
October 1, 1983
Publication Information
Publication: Combustion and Flame
Volume: 52
ISSN: 0010-2180
Subject Category
Inorganic And Physical Chemistry
Accession Number
83A48156
Funding Number(s)
CONTRACT_GRANT: NSG-3245
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available