Comparison of the emissions, drivability and performance of a heavy-auty vehicle when equipped with the original diesel engine and a new natural gas version

In recent natural gas has become increasingly important as an alternative vehicle fule due to the drive to reduce pollutant emissions, especially particulate matters and nitrogen oxides, and because of concern abut tropospherical ozone formation. furthermore, problems with worldwide for energy independency make natural gas an attractive alternative to traditional fuels. All of these factors are leading countries like Iran, which have plentiful reserves of natural gas, to implement energy policies which promote the use of NG in both passenger cars and heavy-duty vehicles. This paper describes the comparison which was made between on-board emissions, performances and drivability of a Heavy-Duty vehicle when equipped with the standard Diesel engine and with a converted natural gas engine. This turnkey project was carried out by Applus + IDIADA for Tousee Khodro Car. Applus + IDIADA took responsibility for the initial mechanical modifications of the egine up to the vehicle prototype and subsequent emission, performance and drivability measurements. The particular challenge of this project was the need to balance fuel economy and applicability for the Iranian market on the one hand with the requirements of a modern combustion concept with low exhaust on the other.