The effect of compression ratio on the CNG-diesel engine

Lim, Pei Li (2004) The effect of compression ratio on the CNG-diesel engine. [USQ Project]


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The objective of this study is to investigate the effects of different compression ratio
on the performance of a diesel engine operating on a dual fuel system using
Compressed Natural Gas (CNG) as the main fuel. The original diesel engine is a fourstroke,
Ford diesel engine with a compression ratio of 22.9:1. In order to
accommodate CNG in diesel engine, the compression ratio has to be reduced to
prevent knock. Therefore, Computational Fluid Dynamics (CFD) method using
FLUENT simulation software is used for this purpose. The engine performance will
be investigated in terms of the mixing quality of CNG and air before injection of
diesel fuel, temperature and pressure distribution, and stream function of the mixture
during the compression stroke. Based on the simulation results, the optimum
compression ratio chosen to operate the CNG-diesel engine without knock is 16.6:1.
At this compression ratio, the engine can operate until the normal operating load
condition where the wall temperature is 373 K before the engine was knocking.

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Item Type: USQ Project
Refereed: No
Item Status: Live Archive
Faculty/School / Institute/Centre: Historic - Faculty of Engineering and Surveying - Department of Mechanical and Mechatronic Engineering (Up to 30 Jun 2013)
Date Deposited: 11 Oct 2007 00:14
Last Modified: 02 Jul 2013 22:30
Uncontrolled Keywords: diesel engine, compression ratio, compressed natural gas (CNG), computational fluid dynamics (CFD), FLUENT
Fields of Research (2008): 09 Engineering > 0913 Mechanical Engineering > 091399 Mechanical Engineering not elsewhere classified
09 Engineering > 0902 Automotive Engineering > 090201 Automotive Combustion and Fuel Engineering (incl. Alternative/Renewable Fuels)
Fields of Research (2020): 40 ENGINEERING > 4017 Mechanical engineering > 401799 Mechanical engineering not elsewhere classified
40 ENGINEERING > 4002 Automotive engineering > 400201 Automotive combustion and fuel engineering

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