Effects of Fuel Injection Conditions on Driving Performance of a DME Diesel Vehicle 2003-01-3193
Since dimethyl ether (DME) is a synthetic fuel, it is possible to make it from natural gas, coal and biomass. It is a low-emission, oxygenated fuel, which does not generate soot in the exhaust. Therefore, it has recently been identified as a possible replacement for diesel fuel.
In Japan, the new short-term emissions regulations will be enforced beginning in 2003, and the long-term emissions regulations are scheduled to be enforced in 2005. In order to meet these more stringent emissions regulations, existing diesel engines would not be as widely used in the near future as they currently are. This will thus bring about a more widespread use of DME engines due to their low emissions potential. Moreover, when the modification of existing diesel engines into DME engines is available at a moderate cost, the wider use of DME engines can be expected.
This study targeted development and application of DME engine technology for diesel engine retrofit, in a used diesel vehicle. Thus, the development of a DME diesel vehicle has been achieved while minimizing the modification of the existing diesel vehicle, modifications which were mainly restricted to the fuel supply system.
Experimental results with a vehicle showed that no particulate matter (PM) was emitted, and NOx emissions could be reduced by a catalyst and EGR. This study demonstrated that the short-term regulations can be met with the proposed DME engine system. Also, satisfactory driving performance and trouble-free operation of the vehicle was observed, with stable operation of the fuel supply system on DME fuel. This work demonstrates that when the DME fuel supply infrastructure is in place, DME diesel vehicles can penetrate the market as a low emission vehicle.