About AAQR

Aims and Scope

Articles online
For contributors
Call for Papers
Guideline for the
Special Issue Proposal
Subscription
Information

Advertising

Contact Us
 
Search for  in   Search  Advanced search  

 

Volume 12, No. 6, December 2012, Pages 1289-1297 PDF(672 KB)  
doi: 10.4209/aaqr.2011.09.0142   

Pollutant Emission Reduction and Engine Performance Improvement by Using a Semi-Direct Injection Spark Ignition Engine Fuelled by LPG

Yuh-Yih Wu, Bo-Chiuan Chen, Anh-Trung Tran

Department of Vehicle Engineering, National Taipei University of Technology, No. 1, Sec. 3, Jhongsiao E. Rd., Taipei 10608, Taiwan

 

Abstract

 

Reducing motorcycle exhaust emissions to improve air quality is important in Asia, due to the large number of motorcycles. This study describes and proposes a lean-burn system for reducing pollutant emissions and improving motorcycle engine performance. The lean-burn system, called semi-direct injection (SDI), is comprised of high-swirl charge, injection during intake-valve opening, and liquefied petroleum gas (LPG) injection. A conventional motorcycle engine with port fuel injection (PFI) and spark ignition (SI) was retrofitted by designing a new intake port with a controllable plate to enhance the swirl of intake flow. The swirl ratio was increased to 3.4, enhancing the turbulence of air flow inside the combustion chamber, and the lean limit was extended to 1.7 of relative air/fuel ratio (lambda). The engine was tested at a low-load region which includes most operating points of the ECE-40 driving cycle. A complete engine performance map was produced and a comparison was undertaken between the new design and regular gasoline engines. The results show that brake-specific energy consumption (BSEC) decreased by 19.2%. Brake-specific exhaust emissions of CO2, NOx and CO were decreased by 27%, 47% and 94%, respectively. HC emissions were increased by 4.5%.

 

 

Keywords: Motorcycle; SI engine; Lean burn; LPG.

 

 

Copyright © 2009-2014 AAQR All right reserved.