modelling of screw compressor capacity control
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Purdue University
Purdue e-Pubs
International Compressor EngineeringConference
School of Mechanical Engineering
1998
Modelling of Screw Compressor Capacity ControlN. StosicCity University
A. KovacevicCity University
I. K. SmithCity University
This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for
additional information.
Complete proceedings may be acquired in print and on CD-ROM directly from the Ray W. Herrick Laboratories at https://engineering.purdue.edu/
Herrick/Events/orderlit.html
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
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CuN •• on. tl<le rock
-v oo k
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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
7
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__ 7 bo r___ 10 bo r
13 bar
· • • M e a s m e n l 7 ba r
A ir Inlet I ba rAir Outlet 5-1 3 bar
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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
Shafl Spe ed 400 0 rp mAir O u l le l 5-13 ba r
\
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4.5l4.0 . '
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
c:
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as
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g .0 3 t,,.=+35 'c 4.o 4. 0 1"' J t , . .=-5 'C, t""=+35 'C l
4
E a3.ot E 3 . o ~ f" -----------------L L, j
- - - - - - -...
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9C1 lcon=+35 .o-C 0... 2
'o 2. 0 / • • • - - - - ----.-- - - - - - - - ----- 'o j 'o
•• •••·•· ............................................ 1.0 1 0 l0
1::::8 .• •· 0 · 0 l
U 0 0 i " I " • " ' < < < I U U 0 0 . : j . , . , ~ ~ , . . . , - ~ ~ r < T ' ~ ~ = = ~ n : : " ~ ~ T r T l . o' ' ' 2000 4000 6000 BOOO 0.0 o.'o 0
.2 0.4 o.'B oB l.O ' O.O 0. 2 0.4 0. 6 O.B 1.0
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Shafl Speed {rpm)
Speed 6000 rp m45003000
___________... - --·
---- Speed 6000 rp m~ 3 0 0 " ] --- 4500 ~ 4 0ii= j ---- 3000 ii=
::.» »3
.. 2001 :::, Q
,./ ~ 2ns "'., [0
u 10 0 ... ... ... .--·. u, .............. "" . ~ 1
'- ........ .....<1
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
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