Ricardo cleans up with bus engines
Page 16
If you've noticed an error in this article please click here to report it so we can fix it.
• Ricardo Consulting Engineers of Sussex has won a contract to develop a clean bus engine with exhaust emissions for the Scandinavian market.
The contract has been awarded by the Co-Nordic Natural Gas Bus Project (CNNGBP) a consortium of bus companies, governments, gas companies, and engine manufacturers.
The engine chosen for development is Scania's 11-litre, six-cylinder diesel DSE, which will be converted by Ricardo's with co-operation from Scania to run on natural gas. The demonstration engine will use Ricardo's patented "Nebula" bowl-in-piston combustion chamber.
Natural gas fuels tend to be difficult to mix with air and slow to burn, so the engine will have a sophisticated Ricardodeveloped electronic control system to manage the combustion process.
It will be charge-cooled, with exhaust gas recirculation (EGR) into the intake air that may also be cooled. A threeway catalytic conveter will be fitted into the exhaust system.
As the engine will run on the spark-ignition principle the diesel injectors will be replaced by spark plugs and the intake air will be mixed with the fuel in the intake manifold.