Design Of Integrated Silent Oil Source And Vibration And Noise Control Research

The underwater hydraulic power source is the core component of the hydraulic power system of marine equipment,and its vibration and noise level is an important parameter index reflecting the comprehensive performance of marine equipment.The vibration noise generated when the oil source is working is the main noise source of the underwater hydraulic power system.The excessive vibration noise will not only cause great physical and mental harm to the staff who have been in the noise environment for a long time,but also interfere with the normal operation of other instruments and equipment.In severe cases,the device may even fail.Therefore,controlling the vibration and noise of the oil source is of great significance to the underwater hydraulic power system and even the entire marine equipment.Based on the two working conditions of the integrated silent oil source on land and water and the requirements for vibration reduction and noise reduction,this paper designs the principle structure of the integrated silent oil source,and takes the designed oil source scheme as the research object,and analyzes the vibration and noise characteristics of the integrated silent oil source.The research mainly includes the following:Through the full investigation of the research related to the vibration reduction and noise reduction of underwater hydraulic power source products and hydraulic systems at home and abroad,combined with the analysis of the characteristics of both water and land conditions,the parameter performance indicators and design ideas of the integrated silent oil source are summarized.The generation mechanism of oil source vibration noise is analyzed,the difference between oil source vibration noise under different working conditions is compared,and the mechanical noise and fluid noise are the main sources of oil source noise,indicating that the underwater working condition oil source vibration and noise situation is more complicated,and the integrated silent oil source scheme design that can work silently under land and water conditions is completed.In view of the pump-pipeline,an important source of vibration and noise caused by the integrated silent oil source,this paper has carried out a detailed study on it.Firstly,by comparing the tooth structure difference and flow pulsation mathematical model between the conventional involute external gear pump and the screw rotor pump,it is shown that the screw rotor pump theoretically eliminates the flow pulsation and oil trapping phenomenon,and can greatly reduce the work of the hydraulic pump.noise.Secondly,the influence of pipeline connection mode,pipeline inlet fluid parameters,pipeline structural parameters and pipeline material on the vibration characteristics of pipeline is studied by controlling single variable of fluid-structure interaction simulation.The results show that the pipeline connection method with short length and less bending number,large pipeline inner diameter and thick wall pipeline,and structural steel material pipeline with high stiffness have higher modal natural frequency and better resistance to stress and strain.,It has excellent resistance to vibration and deformation,and has obvious effects on improving the overall sound and vibration performance of the oil source.However,the change of fluid parameters has little effect on the vibration characteristics of the oil source pipeline.According to the vibration characteristics of the oil accumulator under different working conditions,the modal simulation analysis is carried out in this paper.The results show that the difference between the dry and wet modes is large,and the natural frequency changes are particularly obvious.Compared with the dry mode,the wet mode frequency decreases more greatly,indicating that the additional mass effect of the internal and external fluids cannot be ignored when analyzing the modes of the oil accumulator under different working conditions.The influence of water depth pressure and compensation pressure on the vibration characteristics of the oil accumulator was studied by changing the pressure in the internal and external fluid domains.The results show that the increase of water depth pressure and compensation pressure will cause the oil accumulator mode shape to change sequentially and the modal frequency to decrease.When the water depth pressure is 10 MPa and the compensation pressure is 0.3MPa,the modal natural frequency of the oil accumulator has entered the motor excitation frequency range,indicating that the oil source may have resonance.Subsequently,the structure of the oil accumulator was improved,and the effects of the wall thickness of the coaming plate,the rib method,the aspect ratio and the installation method on the vibration reduction effect of the oil accumulator were studied.The ratio can reduce the amplitude of the vibration mode and increase the natural frequency,which can make the natural frequency of the oil accumulator separate from the excitation frequency of the motor to a certain extent and avoid resonance.Although the natural frequency of the oil accumulator cannot be significantly increased by adding a hoop to fix it in the onshore working condition,it can greatly limit the vibration amplitude,thereby suppressing the vibration of the oil source.