Modelling of Screw Compressor Capacity Control

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Purdue University

Purdue e-Pubs

International Compressor EngineeringConference

School of Mechanical Engineering

Modelling of Screw Compressor Capacity ControlN. StosicCity University

A. KovacevicCity University

I. K. SmithCity University

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Stosic, N.; Kovacevic, A.; and Smith, I. K., "Modelling of Screw Compressor Capacity Control" (1998). International Compressor

Engineering Conference. Paper 1307.http://docs.lib.purdue.edu/icec/1307

CuN •• on. tl<le rock

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E-F" L.ine F-G Circle G-H LnH- J Troc:hoicl J- t< Tn:u:lloidK-A Cir-cle A-1!11 ?grcboiiCIB-C Un•

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Fig . 1: 5/6 and 6/7-127.5 mm Ra ck

G eneate d 'N' Screw Com pre sso r Ro tors

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c.. 40

0.. 30

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· • • M e a s m e n l 7 ba r

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... ..0 1000 2000 30 00 4 000 5000 6 000 7 0 0 0

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Fig. 2: Air Com pre sso r Perform an ces

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• • • Measurements 7 bar

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0.0 0.1 0.2 0.3 0.4 0.5 0.8 0.7 0.6 0.9 1.0Re altive lnle Pressu re

as a Functi on of Shaft Rotational Speed

Fig . 3: Air Com pre ss or P erform ances

as a Funct io n of Sucti on Throttling

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0.0 0.2 0.4 0.6 0.6 I. 0Relative Inlel Volume

Fig. 5: Refrigeration Capacity and COP

as a Function of Shaft Rotational SpeedFig. 6: Refrigeration Capacity and COP Fig. 7: Refrigeration Capacity and COP

as a Function of Inlet Volumeas a Function of Suction Throttling

Modelling of Screw Compressor Capacity Control

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