Vibration And Noise Analysis And Layout Optimization Of Small Ship Distributed Power Plant

As the power plant of the ship,the steam turbine generator set is also the main source of vibration and noise of the ship.When the ship is sailing at low speed,structural noise plays a major role in the sound radiation of the whole ship,and it needs to be strictly controlled.Reducing the vibration of the ship’s power plant is an indispensable important content to reduce the vibration and noise of the ship.The steam turbine generator set used in the traditional ship power plant works at a low speed,the power density of the unit is low,the low frequency vibration is difficult to control,and the vibration energy is large.It is one of the main vibration noise sources of the ship.At the same time,due to the high power of the unit,the size It is too large,and it is more difficult to maintain the cabin later.Compared with the traditional large-scale steam turbine generator set,the small radial turbine generator set has many advantages such as small overall size,light weight,simple manufacturing process and method,low vibration,low noise,long life,etc.Multiple small high-speed radial turbine generator sets are used and distributed.By optimizing the layout,the overall vibration of the steam turbine unit can be significantly reduced.In this paper,based on the typical excitation(unbalanced excitation,airflow excitation,electromagnetic excitation)mechanism of the turbo-generator set,the vibration characteristics of the two turbo-generator sets under the coupling excitation are studied.Based on the finite element analysis theory,two types of turbo-generator sets are established.Simplified shafting model,analyze the first two modes of the two turbo-generator shafts rigid support and elastic support,and carry out the simulation of the vibration characteristics of the two turbo-generator shafts under the combined action of unbalanced excitation,airflow excitation and electromagnetic excitation analysis.Based on the calculation results of the shafting vibration characteristics of the two turbo-generator sets under the coupling excitation,combined with the intake parameters of the turbo-generator set structure,two simplified models of power systems with different powers were established and meshed.The finite element software was used to simulate and calculate the vibration response of the power system coupling mechanism,explore the vibration reduction effect of the small distributed power device,and verify the vibration reduction advantages of high-speed small turbo-generator sets.Finally,while keeping other conditions unchanged,by changing the layout position of the small high-speed turbo-generator set,using several more typical distribution methods,through finite element software to calculate the vibration noise of the power system under different distribution schemes,we get The optimal layout of distributed small power plant.