Swirl, squish and turbulence in stratified-charge engines: Laser-velocimetry measurements and implications for combustion

Conference · Thu Jan 01 00:00:00 EST 1987

OSTI ID:6374461

Fansler, T D; French, D T

Laser-Doppler velocimetry has been used to investigate the effects of piston-bowl geometry (cylindrical and reentrant) and intake-swirl ratio (4.5 and 6.5) on the structure and evolution of the turbulent flow field in a motored engine (compression ratio: 10,6, speed: 600 r/min). High-shear regions and associated turbulence production are observed just inside the bowl entrance around TDC of compression. Before TDC, these regions are created in both geometries by the opposing effects of swirl and squish. As the piston passes through TDC and the bulk squish flow reverses, the high-shear, turbulence-producing region inside the rim of the cylindrical bowl disappears, but it persists within the reentrant bowl as a direct consequence of the geometry.

• Research Organization: Engine Research Dept., General Motors Research Labs.
• OSTI ID: 6374461
• Report Number(s): CONF-870204-
• Resource Relation: Conference: Society of Automotive Engineers international congress and expo, Detroit, MI, USA, 23 Feb 1987; Other Information: 870371
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
INTERNAL COMBUSTION ENGINES
COMBUSTION CONTROL
COMBUSTION KINETICS
HYDRAULICS
VORTEX FLOW
AIR POLLUTION MONITORING
COMPRESSION RATIO
EMISSION
FLOW RATE
FUEL INJECTION SYSTEMS
FUEL-AIR RATIO
HYDROCARBONS
LASERS
OPERATION
PISTONS
SHEAR
TURBULENT FLOW
VELOCIMETERS
VELOCITY
CHEMICAL REACTION KINETICS
CONTROL
ENGINES
FLUID FLOW
FLUID MECHANICS
FUEL SYSTEMS
HEAT ENGINES
KINETICS
MEASURING INSTRUMENTS
MECHANICS
ORGANIC COMPOUNDS
REACTION KINETICS
330100* - Internal Combustion Engines