Rachid Maamri^1,, Fedor Ivanovitsh Abramtshuk², Alexandre Nikolaevitsh Kabanov², Mekhael Sergeevitsh Lipinsky², Yves Dubé¹, Lotfi Toubal¹, Agbossou Kodjo³

Many cities and countries today have programs to convert older, polluting diesel transit buses and trucks to run on clean, economical natural gas. Properly implemented, this is an excellent way to quickly reduce fuel costs, clean up the air and reduce noise with minimum capital costs. A poorly executed conversion program, however, can lead to higher exhaust emissions, much higher fuel consumption, unacceptable power losses, poor durability and high maintenance costs. This article gives the results of our investigation of a forced aspiration gas engine 6GCHN13/14 converted from diesel. The mathematical model of the combustion process specified for the gas engine uses a variable Wiebe combustion factor. Use of the developed characteristic maps has shown improvement of engine power indicators in comparison with that of a naturally aspirated engine, as well as a decrease in average operational emissions with the use of adjustable forced aspiration.

combustion, wiebe combustion factor, mathematical model, natural gas, engine mapping