Noise Mechanism Analysis And Noise Reduction Of Refrigerator Compressor

The compressor is the power source of Refrigerator, at the same time is also the mainsource of noise. With the improvement of people’s living standards, refrigerators andother appliances are becoming more and more high quality requirements, not onlyincluding energy saving, efficiency, noise and vibration levels are becoming more andmore attention. Therefore, low noise and high efficiency compressor can certainlyachieve greater competitiveness in the market.Based on the analysis of noise generation and vibration transmission path of thepiston compressor, respectively, to study the compressor slider-crank mechanismdisturbing noise、electromagnetic noise、bearing noise and exhaust noise, it wasconcluded that the inlet noise was the main source of compressor noise, and the noiseamplitude at frequency of630Hz and630Hz is bigger. These laid the foundation forfurther research of compressor noise.A further research for the intake silencer acoustic performance and fluidcharacteristics had been done. By acoustic finite element simulation analysis，calculatedthe transmission loss. Then, in order to find the optimal combination of differentstructural parameters, a number of effects were studied, including the number ofexpansions; the positions of rigid baffle in the chamber; the position of extended tube;the length of extended tube; Calculating the resistance characteristics, main factorsaffecting the pressure loss were obtained. Finally, the comprehensive performance ofmuffler was improved.Based on the test technique of standing wave tube with double microphones, a foursensor method was developed to measure the transmission loss. The transition of thetapered pipe was used to solve the size inconformity between muffler aperture andstanding wave tube diameter, then get rid of the influence of the tapered pipe, thetransmission loss of muffler itself was obtained. The experimental results and numericalsimulation results have good consistency; On the one hand, verified the feasibility ofsimulation analysis, and also indicated improved performance of muffler afterimprovements.Experimental modal analysis was carried out on the compressor and extracted thefirst seven order modal parameters of the compressor housing. The compressor aremainly high frequency modal frequencies, which focus on3000Hz, explaining thereasons for the bigger compressor noise in the3150Hz band. The weak link in compressor vibration is mainly in the upper shell and the lower shell weld, and thevibration about4000Hz of compressor will excite the vibration at the top of thecompressor. The results provide reference for the optimization of the compressor shell.