Multidimensional computations of premixed charge engine combustion

Thesis/Dissertation · Tue Dec 31 23:00:00 EST 1985

OSTI ID:6875658

Abraham, J

This study examines controlling physical processes in premixed charge engine combustion and reviews status of turbulent combustion modeling in general and engine combustion modeling in particular. A species conversion submodel for premixed charge engine combustion is developed. The model assumes that species concentrations approach their local thermodynamic equilibrium values with a characteristic conversion time that is a combustion of a turbulent mixing time and a chemical conversion time in laminar flames. The model is assessed, as a first step, by making comparisons of computed and measured mean engine cylinder pressures for a range of operating conditions. Computed and measured cylinder pressures agree well in trends and magnitudes during entire duration of combustion. The model is then subjected to a more severe test by comparing computed and measured local and instantaneous turbulence intensities and bulk velocities in an engine cylinder with combustion. The model reproduces adequately bulk velocities and turbulence intensities in unburned gas. The structure of turbulent flames in engines is then examined from the theoretical viewpoint. Nondimensional parameters defining known combustion regimes are reviewed and numerical values of these parameters are estimated.

• Research Organization: Princeton Univ., NJ (USA)
• OSTI ID: 6875658
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800 -- Combustion
Pyrolysis
& High-Temperature Chemistry
CHEMICAL REACTION KINETICS
COMBUSTION KINETICS
DISPERSIONS
ENGINES
FLAMES
FUELS
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
KINETICS
MATHEMATICAL MODELS
MIXTURES
REACTION KINETICS
TURBULENCE