| Now, refrigerator has been necessary in normal living. Noise reduction is very important to people's environment. Therefore, refrigerator compressor of high-efficiency and low-noise has profound significance for energy conservation and environmental noise reduction. There are some relations between energy conservation and noise reduction for compressors. Many methods of noise reduction can influence coefficient of performance (COP) of compressors, and improving efficiency maybe cause noise increase or transformation of frequency spectrum.This paper discusses the effect elements about compressor's COP or causing noise, and how to improve COP or reduce noise. Some researches are introduced about reducing noise.The inner acoustic field is calculated by finite element methods when reduce the volume of lubricating oil. The analytical results are consistent to the experimental data. We can get that the oil influence the distribution of inner acoustic field in some range frequencies evidently.The oil affect inner acoustic field, in result, it affects the acoustic fluid-structure interaction and indirectly affect the noise through shell. The eigenfrequencies of acoustic mode will move down by the oil volume decrease. The eigenfrequencies of shell mode will move up by the constraint adding. Reducing structural noise radiation is an effective method, which can reduce noise but structure almost no change. This paper also discusses the effect of geometrical parameter of three-dimensional shell (i.e. circumferential direction parameter, fillet between the surfaces, geometrical asymmetry structure), which change shell mode. And using methods of adding rib, change radius of curvature or geometrical asymmetry for shell, calculate field point sound press distribution on inner sound source through shell.Based on results, the geometrical asymmetry shell has obvious effect about reducing noise in large range of frequencies, and change radius of curvature can increase eigenfrequency obviously. |
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