Condition monitoring firm CM Technologies (CMT) reports that it has added a fuel injection acoustic emission sensor to collect data for its PREMET X range of two- and four-stroke diesel engine performance indicators.
The new device allows engineers to monitor the acoustic signature of a diesel engine’s fuel injection system to detect any problems with fuel injectors, nozzles, and pumps. Clogged or worn nozzles, leaking injectors, and damaged fuel pumps can affect fuel atomisation and timing, leading to poor engine performance, increased fuel consumption, increased emissions and potentially engine failure.
“Atomisation and fuel injection timing are the most important variables in the combustion process, correlating directly with the amount of fuel consumed and carbon emitted,” said Matthias Winkler, Managing Director, CMT.
“By monitoring fuel injection frequencies in the in the 300kHz to 700kHz range, we can get invaluable insight about problems with fuel injection and combustion. If not detected in time, less than perfect atomisation can lead to excess fuel consumption, after burning or critical component damage.”
Unlike accelerometer-based sensors, which need to be mounted internally and can be affected by mechanical load, high temperatures and pressures, the acoustic emissions sensor is based on non-contact EMAT (Electromagnetic acoustic transducer) technology that requires no access to internal components. It incorporates a built-in amplifier and a signal conditioning module to monitor frequencies in the 200-700kHz range and can measure through coated surfaces, unaffected by pollutants, oxidation or surface roughness.
Depending on where the sensor is placed, different aspects of the fuel injection process can be monitored. For example, if the sensor is placed on the cylinder head the injection and exhaust valve timing can be monitored, while the performance of each nozzle can be recorded by placing the sensor on the relevant tie rod. For trending of historical data measurements should be taken regularly from the same place.
