Centrifugal compressor discharge temperature

Figure 12-61D. Centrifugal compressor surge control schematic diagram shows instrumentation required when primary flow-measuring device is located in centrifugal compressor discharge line. Symbols T = temperature P = pressure A = differential across compressor outlet to inlet. See Reference 89 for a detailed discussion. (Used by permission White, M. H. Chemical Engineering, p. 54, Dec. 25,1972. McGraw-Hill, Inc. All rights reserved.)...

Compressor horsepower is directly proportional to gas inlet temperature. Therefore, it makes sense to cool gas at compressor inlet or between stages. Another reason to cool gas between stages is due to the temperature limitation for the compressor. For centrifugal compressor, this temperature limitation is about 350 F. [I] For certain service, such as compression of oxygen, chlorine, and acetylene, the discharge temperature is limited to 200 F- For horizontal split compressor, thermal stress of bolt joint may limit the discharge temperature. [5]... 

Head coefficient, 156 Head equation, adiabatic, 3 t Head equation, poly tropic, I Head, centrifugal, 156 Head, reciprocating, 58 Heat run test (dry), 413 Helical compressor, 5, 7 adiabatic efficiency, Itil applicalion mnge, 7. ly asymmetric profile, 96 bearings, 116 capacity control, 95 casings, 114 circular profile, 95 cooling, I i 1 discharge temperature (dry), I 17... 

Figure 14-40. Basic simple gas-turbine consists of three principal pieces of equipment (1) compressor that raises pressure of atmospheric air and discharges it to (2) combustion chamber or furnace where the burning of fuel raises air temperature before it enters (3) turbine through which the heated gas expands and does work on the turbine blades. Major part of turbine output goes to drive compressor remainder is available power to drive shaft-connected mechanical equipment such as centrifugal compressor or other. (Used by permission Rowley, L. N. and B. G. A. Skrotzki. Gas Turbines, Power, p. 79, Oct. 1946. McGraw-Hill, Inc. All rights reserved.)...

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. ... 

How about the compressor discharge pressure What is this controlled by Answer—the condenser. The compressor discharge pressure has nothing whatsoever to do with the compressor. And this statement is true regardless of whether the compressor is a reciprocating or centrifugal machine, or fixed- or variable-speed. It is the condenser temperature that determines the compressor discharge pressure. 

The centrifugal compressor is a machine that converts the momentum of gas into a pressure head. The compressor pressure ratio (PD/P,) varies inversely with mass flow (W). For a compressor running at constant speed (co), constant inlet temperature (Tj), and constant molecular weight, the discharge pressure may be plotted against mass flow (Curve I in... 

A desuperheater conlrol-syslem can be used to re late the temperature in a centrifugal compressor. Such a system can be used to meet the maximum discharge-temperature of the compressor. 

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