Centrifugal Compressors and Surge

Have you ever heard a 12,000-hp, 9000-rpm, multistage centrifugal compressor go into surge The periodic, deep-throated roar emitted by the surging compressor is just plain scary. Machines, quite obviously, are not intended to make such sounds. But what causes surge  

Another question What happens to the amperage load on a motor-driven centrifugal compressor when the molecular weight of the gas increases 1 ask this question in the following context  

We ought to be able to answer this question with Robert Mayer s equation—also called the Second Law of Thermodynamics (see Chap. 34), which states that motor amperage (or electrical work) is proportional to 

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Tj = suction temperature, a constant = discharge pressure, a constant Pj = suction pressure, a constant K = ratio of the specific heats, C / 

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Spillback bypasses the compressor discharge gas, back to the compressor suction. This is a relatively energy-inefficient way to increase the evaporator temperature. Spillback is discussed in Chap. 28, Centrifugal Compressors and Surge. ... 

Chapter 35 Centrifugal Compressors and Surge 429 35.1.3 Aerodynamic Stall... 

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