Relationship between centrifugal compressor noise and the medium
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Hello, fellow sailors: I have a question I’d like to ask the experts here. One of our centrifugal refrigerant compressors makes an extremely loud noise, while another one makes only a moderate level of noise – it’s possible to work with that one without wearing earplugs. I was wondering which factor is most closely related to this noise. Thank you very much.
There are two units, one with high noise level and the other with low noise level. What are the differences in their operating parameters? What is the difference between layout and piping?
Piping systems, the condition of mechanical equipment, and processing capacity
Generally, a higher compression ratio results in a relatively higher shaft power under the same conditions. However, in your case, I suspect that there is an issue with exhaust flow or a problem with the compressor itself, which prevents it from achieving a normal compression ratio. (For reference only)
Is it due to a problem with the compressor itself, such as worn vapor seals?
Thank you, I’ll think about it more carefully
Generally speaking, centrifugal compressors generate quite a lot of noise; the noise level measured next to our air compressors exceeds 100 decibels. Based on an article I read online, here is an analysis: 1. Gas flow dynamic noise: This includes rotational and turbulent noise. When the impellers rotate at high speeds, the blades move periodically, causing the gas particles to be subjected to periodic forces. This results in pressure waves that travel at the speed of sound. This causes pneumatic noise. 2. Mechanical vibration noise: Noise generated by vibrations caused by factors such as rotor imbalance, bearing friction, and gear meshing or failure. 3. Noise generated by the interaction between the two components: The vibration caused by the rotation of the blades is transmitted through the pipes; pressure waves and vortices often occur at the bends in the pipes, leading to vibrations that increase noise levels. In particular, when the frequency of the air flow pressure waves matches the natural vibration frequency of the pipes, intense resonance occurs, resulting in a sudden increase in noise. In severe cases, this can damage the machine. 4. When a centrifugal compressor is driven by an electric motor and a gear speed-up device, poor alignment causes vibration, which in turn generates noise. In summary, the noise of centrifugal refrigeration compressors is, apart from mechanical vibration noise and resonance phenomena, mainly related to the gas pressure and flow rate, that is, to the circumferential speed of the impeller and the flow velocity of the gas.