Numerical Simulation Of Refrigerating Compressor Acoustic Characteristics And Research Of Noise Reduction

Refrigerator plays a very important role in people's daily life along with the development of society economy. Therefore, it is very important to reduce the noise of refrigerator for improving environment of person's work and living. A lot of research works on noise reduction of refrigerator reciprocating compressor, which mainly focus on suction muffler and shell optimization, are conducted in this paper, and then some satisfactory research results are obtained.Based on analysis in noise sources identification and transfer path of refrigerator compressor, the reasons of noise creation and methods of noise reduction and current research situation on compressor noise control are summarized. At he same time, muffler styles and evaluation of acoustic performance and analysis methods of acoustic characteristic are introduced detail by detail.A finite element method (FEM) was suggested to simulate the inner field of muffler, by which the transmission loss (TL) could be calculated, since the complicated pressure-distribution couldn't be predicted by plane wave theory. And a number of effects are studied, including the positions of rigid baffle in the chamber and the positions of extended tube and the positions of inlet tube. According to the analysis results, we can find that the positions of baffle affect the acoustic attenuation of muffler in the higher frequency region obviously;the positions of extended tube on baffle affect the frequency in which the noise reduction is the maximum at the low frequency region besides acoustic performance of muffler at high frequency region;the positions of inlet pipe affect the number of frequencies in which the noise-reduction is the minimum at the high frequency region, and make for improvement of the acoustic performance when close to bottom of muffler.It is an important method that reduces shell's sound radiation which can eliminate compressor noise. A number of effects, that is, the sound radiation of shell is affected by different parameters, are studied. According to the research results, we can derive some conclusions, including: the sound power is the minimum when pump and shell are connected by support spring;radial force can bring maximum sound radiation, and sound power is the minimum when axial force is applied;the sound radiation can decrease along with thickness of shell increased as well as damp of shell;large radius of blend make for noise reduction of compressor.A numerical analysis method was suggested to simulate the sound radiation of compressor's shell based on Fluid Structural interaction (FSI), by which the distribution of pressure could be calculated considering the influence of lubrication oil. Sound radiation of shell is influenced evidently ranged from 1000Hz to 2000Hz since the presence of lubrication oil. The frequency which the radiation value is the maximum has moved to high frequency when the height of oil rises, and the peak value also has increased gradually, on the contrary sound radiation has a little change at other frequencies region.