A Comparative Evaluation of the Performance of a Gasoline and CNG Fuelled Retrofitted Spark Ignition Car Engine.

M.U. Aslam, H.H. Masjuki, M.A. Kalam, H. Abdesselam, T.M.I. Mahlia and M.A. Amalina

Department of Mechanical Engineering

University of Malaya, 50603, Kuala Lumpur, Malaysia.

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Manuscript received May 18, 2005

Revised June 17, 2005




This paper presents experimental results obtained from running a 1.5 litre, 4-cylinder, retrofitted spark ignition engine. The basic intent of the present work is to compare experimentally the potential of using CNG (compressed natural gas) with respect to gasoline at different loading conditions. The engine was converted to computer integrated bi-fueling system from a gasoline engine and was operated separately either with gasoline or CNG using an electronically controlled solenoid actuated valve system. A PC based data acquisition and control system was used for controlling all the operation. A comparative analysis of the performance and emissions has been made with respect to gasoline and CNG. Based on the experimental results, it is transparent that CNG shows low power, low brake specific fuel consumptions, higher efficiency and lower emissions of CO, CO2, HC but more NOx compare to gasoline. For wide spread adoption of CNG vehicles it is recommended to develop lighter CNG storage tank and extensive networks of CNG supply stations through out the country.


Keywords: Air pollution, alternative fuel, retrofitted engine, engine performance and energy security.




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