PERFORMANCE RELATED EXHAUST EMISSIONS FROM HEAVY-DUTY DIESEL-ENGINES

Exhaust emissions from heavy duty diesel engines were measured on a engine test bed over transient and steady state cycles. The engines covered the range found in UK diesel vehicles, from 4 litres naturally aspirated to 14-1 turbocharged/intercooled and were tested in a mechanical condition to represent a well maintained engine in service. Emissions and operational variables were recorded each second throughout the tests. The results have been analysed to show how rates of emission vary with operating conditions, the effects of different engine types, the relationships between pollutants and to see how well the engines complied with emission control standards. Combined with information on the operating characteristics of commercial vehicles, the data provide a basis for estimating emissions on a local or regional scale.