The Design And Research Of Noise Reduction Of Ventilation Noise Of Self-Ventilated Low-Voltage Asynchronous Electric Motor

With the development of society and the advancement of industry,under the background of environmental protection,the problem of noise pollution caused by electric motors used in various fields is becoming more and more serious.With the development and advancement of industrial technology,motor noise indicators have become one of the standards for measuring the quality of motors.In order to improve the efficiency and design quality of the motor and improve the competitiveness of the company in the vast market,reducing the motor noise effectively has become an area in which international and domestic related industries are competing to enter.In this paper,a self-fan-cooled low-voltage motor of company is mainly studied to reduce its ventilation noise and develop a noise reduction optimization scheme.The specific work of this paper is divided into the following aspects:(1)Firstly,motor radial centrifugal fan and hood model are established.The UG NX10.0 3D model software from Siemens is used to study and establish the equivalent model and optimized model of the prototype fan and hood.The geometry topology optimization and improvement of the radial centrifugal fan and the motor hood were studied.The meshing strategy of the equivalent model is to study the method steps for setting the boundary conditions for the simulation.(2)Secondly,flow field and sound field of radial centrifugal fan are analyzed and researched.The ANSYS software FLUENT module was used to simulate the flow field.Four kinds of turbulence models are used to simulate the flow field constant value of the fan.The wind pressure,tubulence energy and vorticity cloud map are used to analyze the turbulence model and analyze the noise generation mechanism.The unsteady value simulation of the sound field is carried out by the initial solution of the numerical simulation of the flow field.The FLUNT module of ANSYS software is used to simulate the sound field.The LES(Large Eddy Simulation)is combined with the FW-H in the Acoustic noise module.The equation(Ffowcs-Williams & Hawkings)acoustic comparison method performs noise prediction and simulation of the sound field.By setting the rotational speed under different working conditions,the noise monitoring points at different positions are analyzed,and the noise spectrum map is obtained by fast Fourier transform(FFT),and the distribution characteristics and variation laws of noise are analyzed.(3)In the end,design and testing ventilation noise reduction of fan and wind cover are optimized.According to the mechanism of ventilation noise,two optimization design schemes of fan blade perforation and wind cover with circular hole are proposed respectively,and compared with the simulation data of the ventilation noise field of the prototype fan and wind cover,and the 3D printing of the perforated fan and the enterprise workshop test are carried out.The actual noise value is obtained,the reliability and effectiveness of the optimization scheme are verified,and the characteristics and engineering applicability of the optimization scheme are summarized.