The Study Of The Marine Propulsion System Alignment With Air Spring Vibration Isolation System

Ship propulsion plant of host-air vibration isolation system is an effective device tolower vibration noise and will have a positive impact in propulsion shafting. For ship safety,power plant simulation calculation, shafting elastic centering computing and axle bearingforce analysis, the research of ship propulsion shafting alignment problem has very importanttheoretical signiifcance and practical value. Based on the ship shafting centering and vibrationisolation theory and and taked advantage of shipping host air isolation system, the paper madeship propulsion shafting as the research object to research theoretical calculation of shaftingcertering and numerical simulation.In this article, through theoretical analysis and numerical simulation on the shaftingcorrection principle, calculation method, airbag vibration isolation effect were studied. Themain work includes:(1)Accordingto the theory of the ship shafting alignment and vibration isolation, throughcalculating amplitude-frequency curves of the system, the paper analyzed one layer vibrationisolation system and double layer vibration isolation system. Results show that the vibrationisolation coefifcient of double-layer vibration isolation system is lower which proves thatdouble layer vibration isolation relative single layer has good vibration isolation;(2)Based on the basic principle and properties of the airbag vibration isolator, simpliyfing theairbag vibration isolator for elastic support, simplifying the vibration isolation objects to thequality system, study mechanical properties of air isolation system, set up air vibrationisolation system of coordinate system and the movement differential equation;(3)According to the ifnite element method in ship propulsion shafting alignment, using theifnite element software to establish ifnite element model，the paper calculated and analyzednatural frequency and vibration mode shaft system of the ship shafting. The results show thatthe shafting vibration is coupled vibration form rather than a simple twist or bend，and thedisplacement response curves under impact load are studied; (4) Simulated host ship propulsion shafting of loading airbag vibration isolation system,paper numerically obtained the bearing displacement response curve of loading airbagvibration isolator before and after. Through comparison and analysis, air vibration isolatoreffectively reduce ship propulsion shafting transverse interference and bearing lateral,improve the effect of the host on the ship.