Research On Vibration And Noise Reduction Of Marine Gearbox Under Internal Excitation

Chinese exploration and utilization of marine resource,have becomes more attention and focus on the key equipment of ships.It is clear that marine gearbox is an important and basic part of ship.At the present time,high speed,large load,light weight and smooth operation and quietness of the marine gearbox under developmental direction.Therefore,it is more important to optimize the vibration and noise reduction of the marine gearbox.In this paper,a 500kW Marine gearbox was studied to optimize its vibration and noise reduction under internal excitation.The main research as followed:By using ADAMS,a multi-body dynamics simulation software,to analyze the rigid body dynamics of the Marine gearbox transmission system,so as to obtain the excitation forces in the time-domain and frequency-domain of the bearing center position.The obtained internal excitation is taken as the load condition of the finite element model of the gearbox to conduct modal analysis and harmonic response analysis,it is necessary to obtain the vibration response of the gearbox body under the action of internal excitation.Then,in the Virtual.Lab,an acoustic simulation software,the responses velocity from vibration of gearbox has been chosen,boundary conditions in acoustic boundary element method,which is used to calculate the vibration noise of gearbox model.By using the acoustic transfer vector method(ATV),to solve the the panel acoustic contribution of gearbox,that screen out the regions with large contribution in noise,that selected as the target areas for vibration and noise reduction optimization.There are two schemes of vibration and noise reduction optimization have designed for target areas:(1)Through adding stiffeners in these areas,the stiffness of the gearbox is increased,that reduce the vibration on the surface of the gearbox and thus restrain the radiation noise of the gearbox.And also using the shape optimization function in ABAQUS software to optimize the shape of stiffeners.In order for the superficial area of stiffeners was reduced,than as much as possible to reduce the radiation noise source under the condition that the stiffness of the gearbox was not weakened.(2)By adding constraint damping to the target optimization region,the vibration energy of the gearbox surface is absorbed,so as to achieve the purpose of noise reduction.And using the topology optimization function in ABAQUS software to improve the structure of constrained damping,so that obtain the optimal effect of vibration and noise reduction with as least damping materials as possible.Finally,acoustic simulation and harmonic response verification are carried out by two optimization design schemes respectively,and the effects of those two schemes are compared and analyzed,providing reference for the subsequent research on vibration and noise reduction of marine gearbox.