Injection Noise and Its Relation to Fuel Pump and Engine Noise

It is often pretended that the injection nozzles of diesel engines are substantial noise generators. This statement was investigated on a truck diesel engine with the result that the nozzles are not a substantial source of noise on the engine. The task was to find out the principles as well as the composition of the noise components radiated from the nozzles.

Further investigations in an anechoic chamber revealed the cause of the nozzle noise and showed also several possibilities for its reduction.