The power measurement of main propulsion system on the new vessels can classify the direct method which was acquired from the shaft system using strain gauge. And the indirect method which converted and summed from all of cylinders combustion pressure...
The power measurement of main propulsion system on the new vessels can classify the direct method which was acquired from the shaft system using strain gauge. And the indirect method which converted and summed from all of cylinders combustion pressure using mechanical or electrical pickup device during the sea trial. This power is fluctuated by external factors which was influenced by various sea motions with long time interval and by internal factors which was influenced by varying torques of torsional vibration and bending moment, due to mis-aligned shaft and whirling vibration with short time interval. In this paper, the statistical analysis method fur the shaft power measurement using strain gauge in marine vessels are introduced and identified. Three actual models are used for the direct coupled system between low speed two stroke diesel engine and propeller, the coupled system via reduction gear between four stroke medium speed diesel engine and propeller.