Under low loads and in the case of nozzle with a central injection hole, the smoke intensity slightly rises, but the fuel economy doesn't deteriorate.

Taking Diesel 495Q as an example, methods and measures to reduce low-speed smoke intensity and fuel comsumption of diesels by rational match of both mentioned are stated.

Investigation reveals that smoke particles kinestate is decided mainly by the relative velocity between smoke cloud and particles and the smoke cloud turbulent intensity.