1998-10-19

Measurement and Modeling of the Flow-Field in a DI Diesel Engine: Effects of Piston Bowl Shape and Engine Speed 982587

The flow-field of an automotive DI Diesel engine is characterized by experiments in a motored engine using Laser Doppler Velocimetry and by CFD simulations. Only one cylinder is active and a specific swirling intake duct is used. Various bowls with different shapes are investigated: fiat or W-shaped bowls, with or without re-entrant. The influence of engine speed is also studied.
The mean velocity and turbulence evolutions are measured with back-scatter LDV experiments using an optical access in an extended piston.
The simulations are performed using the KMB code, a modified version of KIVA-II. Along with the detailed flow-field description, integral quantities characterizing the flow are derived.
The comparison between LDV data and CFD results is shown to be satisfactory. The effects of geometry and engine speed on spatial profiles and temporal evolution of mean and turbulent velocities are correctly reproduced. This investigation has allowed a better understanding of the piston bowl shape effects on the combustion chamber flow. Among these effects, the role of the re-entrant in the W-shaped bowls is shown to increase both swirl number and turbulence level around TDC.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Refinement of a 0D Turbulence Model to Predict Tumble and Turbulent Intensity in SI Engines. Part I: 3D Analyses

2018-01-0850

View Details

TECHNICAL PAPER

Conjugate Heat Transfer in CI Engine CFD Simulations

2008-01-0973

View Details

TECHNICAL PAPER

Fuel Spray Trajectory and Dispersion in a D.I. Diesel Combustion Chamber

890462

View Details

X