FIBRE OPTIC SENSOR FOR ONLINE MONITORING OF OIL FILM PRESSURE IN ENGINE MAIN BEARING
The oil film pressure is one of the key parameters in journal bearings influencing the performance of the bearings. A fibre optic sensor was developed for online determination of oil film pressure in journal bearings. The sensor head is integrated in the sliding surface of the bearing providing the possibility to measure the actual oil film pressure under load without disturbing the actual tribological contact. The sensor consists of two optical fibres, one to illuminate the measurement membrane consisting of bearing material and the other to collect the reflected light. The intensity of the reflected light is detected and converted to pressure data by using the calibration data. Functionality of the sensor can be confirmed after the mounting and between the tests by measuring the spectrum of the light reflected back to the input fibre. This way the distance between membrane and sensor head can be accurately calculated. Four optical sensors were integrated in a hydrodynamic journal bearing of a W(a)rtsil(a) Vasa 4R32 LN E medium speed diesel engine with four cylinders, maximum power of 1640 kW and rotating speed on 750 rpm. Online engine tests were carried out with different loads to study the sensor operation in real operating conditions. Test drives were repeated after several hundred hours of the engine use. The results showed differences in bearing pressure depending on the position of the sensor and on the operating cycle of the cylinders. The pressure peaks of all four cylinder work cycles could be identified in the measured pressure curves and the pressure variations within the pressure curves fit well to the diesel engine’s work cycle and mass forces. The optical sensor was capable to measure the oil film pressure in journal bearing with a good sensitivity and repeatability during the tests which could be observed by comparing the results from repeated measurements and by studying the noise of the results. The distance measurements showed that the sensor heads were integrated with robust riveting joint, any movements were not observed during the long test period.
Helena Ronkainen Markku Kapulainen Ari Hokkanen Ingmar Stuns Simo Varjus Raimo Turunen Sami Nyyssoenen Jari Halme
VTT Technical Research Centre of Finland,Finland
国际会议
上海
英文
1-9
2013-05-13（万方平台首次上网日期，不代表论文的发表时间）