This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Analysis of the Impact on Diesel Engine Fuel Economy and Emissions by Variable Compression Ratio Using GT-Power Simulation
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 12, 2010 by SAE International in United States
Annotation ability available
Variable compression ratio in conjunction with a control system is an effective way to improve performance and reduce emissions in a diesel engine. There are various methods that may be employed that include geometry changes and varying valve timing to change the effective compression ratio.
In this paper, a simulation study is presented that is based on a modern, multi-cylinder, fixed compression ratio diesel engine equipped with exhaust gas recirculation (EGR) and a variable geometry turbocharger (VGT). The engine is represented using the GT-Power code, and includes a predictive combustion model. The aim of the investigation is to identify the impact of variable compression ratio on fuel economy and emission reduction and whether realistic optimal conditions exist.
This paper describes how a formal design of experiments procedure is used to define the simulation conditions. Cost functions are defined with different weights for fuel consumption, NOx and soot emissions. The presentation of optimal simulation results map shows the best operating point in relation with corresponding compression ratio, EGR percentage and VGT strategy across the load range of the engine.
The results demonstrate that the variation of compression ratio with engine operating conditions can achieve fuel consumption benefits while meeting current exhaust emissions requirements.
CitationZhu, Y., Stobart, R., and Deng, J., "Analysis of the Impact on Diesel Engine Fuel Economy and Emissions by Variable Compression Ratio Using GT-Power Simulation," SAE Technical Paper 2010-01-1113, 2010, https://doi.org/10.4271/2010-01-1113.
- Liu Yongchang “Thermal Process Simulation of Internal-combustion Engine,” China Machine PRESS February 2005
- Gamma Technologies “GT-Power User Manual” July 2007
- Montgomery, D.T. Reitz, R.D. “Optimization of Heavy-Duty Diesel Engine Operating Parameters Using A Response Surface Method,” SAE Technical Paper 2000-01-1962 2000
- Drangel, H. Olofsson, E. Reinmann, R. “The Variable Compression (SVC) and the Combustion Control (SCC) - Two Ways to Improve Fuel Economy and Still Comply with World -Wide Emission Requirements,” SAE Technical Paper 2002-01-0996 2002
- Wijetunge, R.S. Hawley, J.G. Vaughan, N.D. “Application of Alternative EGR and VGT Strategies to a Diesel Engine,” SAE Technical Paper 2004-01-0899 2004
- Yang, B. Keller, P. “Analysis of Diesel Engine Emissions Reduction by Late Intake Valve Close and VGT Turbocharger Using 1-D Simulation,” SAE Technical Paper 2008-01-2444 2008
- Bai, M. Lv, J. Shao, Z. “A Study of Performance Development and Optimization of 6106 Diesel Engine,” SAE Technical 2008-01-1725 2008