Study of velocities and turbulence intensities measured in firing and motored engines

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:7203044

Hall, M J

Laser Doppler velocimetry was used to make cycle-resolved velocity and turbulence measurements under motoring and firing conditions in a ported two-stroke homogeneous charge S.I. engine, and motoring measurements in a valved engine. Turbulence intensities in the valved engine were found to be less than in the ported engine due to lower intake velocities and longer decay times. The effect of the intake velocity of TDC turbulence intensity was measured. Velocity and turbulence measurements were made at three engine speeds for three different intake flow rates in the ported engine. The goal was to determine whether intake velocity or engine speed plays a greater role in determining the magnitude of the TDC turbulence intensity. The TDC turbulence intensities were found to be relatively insensitive to the intake velocity at constant engine speed, and tended to scale more strongly with engine speed for a given mass flow rate. For the combustion measurements, the engine was operated at speeds of 600, 1200, and 2400 rpm on stoichiometric and lean propane-air mixtures. Velocity measurements were made in swirling and non-swirling flows. The measurements were made ahead, through, and behind the flame in an effort to determine the effect of the combustion on engine turbulence. The turbulence intensities and swirl velocities were found to scale approximately linearly with engine speed.

• Research Organization: Princeton Univ., NJ (USA)
• OSTI ID: 7203044
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
CHEMICAL REACTION KINETICS
COMBUSTION KINETICS
ENGINES
FLUID FLOW
FUEL INJECTION SYSTEMS
FUEL SYSTEMS
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
KINETICS
MEASURING METHODS
REACTION KINETICS
THERMODYNAMIC CYCLES
TURBULENCE
VELOCITY
VORTEX FLOW