Browse Publications Technical Papers 2003-01-3148
2003-10-27

Determination of Residual Gas Fraction in IC Engines 2003-01-3148

The objective of this study is to achieve a general understanding of gas exchange phenomena to develop a model for predicting the residual gas content. The knowledge of the cylinder-charge composition is important for the thermodynamic analysis of the combustion process of IC engines. Therefore, the amount of fresh air and fuel as well as the residual gas fraction has to be known. The residual gas mass strongly depends on valve train parameters and operating conditions.
In this study, the residual gas fraction has been determined by using in-cylinder gas sampling from the combustion chamber of a 4-stroke SI engine. The gas sampling valve was flush-mounted to the combustion chamber walls. The gas samples were taken after the gas exchange and analysed for its CO2 concentration. In combination with the analysis of the exhaust gas composition, the calculation of the residual gas fraction is possible. The residual gas fraction of the tested engine was determined for a wide operating range including variable valve train conditions.
The prediction of the residual gas content using a thermodynamic gas exchange model correlates well with experimental results. The calculated mass flow is used for further investigations. Different phases during the gas exchange process could be identified, and additional information on the influence of different valve train parameters could be obtained.

SAE MOBILUS

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

Access SAE MOBILUS »

Preview Document Add to Cart
Members save up to 16% 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

A Further Approach to Controlled Auto- Ignition Using a Sequence of Low-Temperature Combustion-States

2010-32-0087

View Details

TECHNICAL PAPER

The Method of Measuring Air-Fuel Ratio by Radical Luminescence in High Combustion Pressure

1999-01-0507

View Details

TECHNICAL PAPER

Direct In-cylinder CO2 Measurements of Residual Gas in a GDI Engine for Model Validation and HCCI Combustion Development

2013-01-1654

View Details

X