A Study On Shafting Vibration Of Large Ship In Regular Wave

All the time since shafting alignment and vibration research are seldomconsidered the influence of ship deformation, research and most of shipdeformation is also out of the ship structure strength check purpose. With theincreasingly large ships, sailing in the ocean when the relative deformation is moreand more apparent, and the wave is the main dynamic load of ship navigation, hulldeformation under the action of waves is dynamic, so the influence which produces tothe centering of shafting and vibration can not be ignored.This paper takes a8530TEU container ship as the research object, thecalculation of hull was in different heights and different phase of the waveload, by loading the appropriate constraint and wave load, calculate the deformationof ship hull in waves, analyzes the bearing displacement effect on shafting alignment,and then studies the bearing support stiffness change and the influence law of shaftingvibration characteristics, the main works can be seen as follow:(1)For Calculating dynamic wave pressure under different phase with AQWA,and transforming it into pressure file which is available for the ANSYS directlyread.Using APDL achieve the target that the underwater unit can beupdated automatically, making an accurate description of wave loads act on ship hull.(2)For analysising the load distribution of container ship, calculating deforma-tion of ship in wave load. The calculation results shows, the same conditions with thepassage of the hull deformation phase wave changes with sinusoidal function changes(3)Studying on the changes of waves under the action of ship deformation afterthe shafting alignment, compared with the linear correction, the ship under wave loadlarge state after deformation in the school after the change, the tail shaft bearingforce is very large, and the emergence of individual positions on the shaft from thebottom surface of the bearing; alone each bearing with the wave phase change thereaction force is a sinusoidal wave,and the phase and synchronous. The stiffnesscalculation of bearing lubrication oil film, the preparation of a matlab program to calculate the oil film stiffness.(4)Analysising the variation regularity of shafting vibration of ship hulldeformation, found that compared to the straight shaft, shaft bending naturalfrequency is lower, and with the increase of frequency number, reduce the moreobvious; the ship shafting and ship aft stern tube bearing bearing, intermediatebearing stiffness of the shaft dynamic frequency have a certain influence.