Refrigeration Compressor
description
Transcript of Refrigeration Compressor
Refrigeration Compressors
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN
A Trane Air Conditioning Clinic
© American Standard Inc. 2000
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Vapor-Compression Refrigeration
expansionexpansiondevicedevice
condensercondenser
compressorcompressor
evaporatorevaporator
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
expansionexpansiondevicedevice
A
F condensercondenser
pres
sure
pres
sure
Refrigeration Cycle
B
CE D
compressorcompressor
enthalpyenthalpy
evaporatorevaporator
period one
Compressor Types
Refrigeration Compressors
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
scrollreciprocating
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
helical-rotary
centrifugal
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Reciprocating Compressor
pistonpistonrefrigerantrefrigerantvaporvapor
cylindercylinder
dischargedischargevalvevalve
rodrod
suctionsuctionvalvevalve
intake stroke
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Reciprocating Compressor
suctionsuctionvalvevalve
dischargedischargevalvevalve
compressionstroke
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Reciprocating Compressor
dischargedischargevalvevalve
suctionsuctionvalvevalve
dischargedischargeopeningopening
headspaceheadspace
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Reciprocating Compressor
suction suction openingopening
motormotor
pistonpiston
cylindercylinder
crankshaftcrankshaft
rodrod
dischargedischargeopeningopening
headspaceheadspace
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Scroll Compressor
stationarystationaryscrollscroll
drivendrivenscrollscroll
intakeintake
dischargedischarge
intakeintake
dischargedischargeportport
motormotorshaftshaft
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Scroll Compressor
journaljournalbearingbearing
motormotorshaftshaft
drivendrivenscrollscroll
directiondirectionof rotationof rotation
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Scroll Compressor
dischargedischargeportport
intakeintake
intakeintake
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Scroll Compressor
intakeintakephasephase
compressioncompressionphasephase
dischargedischargephasephase
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Scroll Compressor
motormotor
scrollsscrolls
domedome
suctionsuctionopeningopening
dischargedischargeopeningopening
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Helical-Rotary (Screw) Compressor
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Helical-Rotary Compressor
male rotormale rotor
female rotorfemale rotor
housinghousing
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Helical-Rotary Compressor
pocket of refrigerant vaporpocket of refrigerant vapor
intakeintakeportport
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Helical-Rotary Compressor
meshing pointmeshing pointdischargedischarge
portport
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Helical-Rotary Compressor
motormotorrotorsrotors
slide valveslide valve
suctionsuctionopeningopening
dischargedischargeopeningopening
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Centrifugal Compressor
impellerimpeller
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Centrifugal Compressor
volutevolute
diffuserdiffuserpassagespassages
radial radial impeller impeller passagespassages
bladesblades impellerimpeller
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Centrifugal Compressorrefrigerant refrigerant enters enters diffuserdiffuser
path through compressorpath through compressor
velo
city
velo
city
stat
ic pr
essu
rest
atic
pres
sure
refrigerantrefrigerant enters impellerenters impeller
refrigerant refrigerant enters voluteenters volute
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Centrifugal Compressor
motormotor
impellerimpellersuctionsuction
inletinletvanesvanes
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Open Compressor
compressorcompressorcrankshaftcrankshaft
housinghousing
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Hermetic Compressor
motormotor
housinghousing
compressorcompressorpistonpiston
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Semihermetic Compressor
compressorcompressorcrankshaftcrankshaft
motormotor
housinghousing
pistonpiston
period two
Compressor Capacity Control
Refrigeration Compressors
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Methods of Compressor Unloading
Reciprocating Scroll Helical-Rotary Centrifugal
Cylinder Unloaders
Cycle On and Off
Slide Valve
Inlet Vanes
Variable Speed
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Cylinder Unloaders
unloaderunloadervalvevalve
refrigerantrefrigerantvaporvapor
dischargedischarge
unloaderunloadersolenoid valvesolenoid valve
controllercontroller
cylindercylinderpistonpiston
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Cylinder Unloaders
unloaderunloadervalvevalve
refrigerantrefrigerantvaporvapor
unloaderunloadersolenoid valvesolenoid valve
controllercontroller
dischargedischarge
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Capacity Versus Suction Temperature
suction temperaturesuction temperature
capa
city
capa
city
50°F50°F[10°C][10°C]
40°F40°F[4.4°C][4.4°C]
20°F20°F[-6.7°C][-6.7°C]
30°F30°F[-1.1°C][-1.1°C]
40 tons40 tons[140.7 kW][140.7 kW]
20 tons20 tons[70.3 kW][70.3 kW]
0 tons0 tons[0 kW][0 kW]
6 cylinders6 cylinders
4 cylinders4 cylinders
2 cylinders2 cylinders
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Compressor Unloading
suction temperaturesuction temperature
capa
city
capa
city
50°F50°F[10°C][10°C]
40°F40°F[4.4°C][4.4°C]
20°F20°F[-6.7°C][-6.7°C]
30°F30°F[-1.1°C][-1.1°C]
40 tons40 tons[140.7 kW][140.7 kW]
20 tons20 tons[70.3 kW][70.3 kW]
0 tons0 tons[0 kW][0 kW]
6 cylinders6 cylinders
AB
DC
EF
4 cylinders4 cylinders
2 cylinders2 cylinders
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Alternating Cylinders On and Off
suction temperaturesuction temperature
capa
city
capa
city
50°F50°F[10°C][10°C]
40°F40°F[4.4°C][4.4°C]
20°F20°F[-6.7°C][-6.7°C]
30°F30°F[-1.1°C][-1.1°C]
40 tons40 tons[140.7 kW][140.7 kW]
20 tons20 tons[70.3 kW][70.3 kW]
0 tons0 tons[0 kW][0 kW]
25 tons25 tons[88 kW][88 kW]
6 cylinders6 cylinders
AB
DC
4 cylinders4 cylinders
2 cylinders2 cylinders
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Cycling On and Off
onon ononoffoff offoff
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Cycling Scroll Compressors
nominalnominalcapacitycapacity
10 tons10 tons[35 kW][35 kW]
20 tons20 tons[70 kW][70 kW]
30 tons30 tons[105 kW][105 kW]
40 tons40 tons[140 kW][140 kW]
# of# ofcylinderscylinders
activeactive
22
44
66
88
# of# ofcompressorscompressors
activeactive
11
22
33
44
stepstep
11
22
33
44
reciprocatingreciprocating scrollscroll
nominalnominalcapacitycapacity
10 tons10 tons[35 kW][35 kW]
20 tons20 tons[70 kW][70 kW]
30 tons30 tons[105 kW][105 kW]
40 tons40 tons[140 kW][140 kW]
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Cycling Scroll Compressors
suction temperaturesuction temperature
capa
city
capa
city
50°F50°F[10°C][10°C]
40°F40°F[4.4°C][4.4°C]
20°F20°F[-6.7°C][-6.7°C]
30°F30°F[-1.1°C][-1.1°C]
40 tons40 tons[140.7 kW][140.7 kW]
20 tons20 tons[70.3 kW][70.3 kW]
0 tons0 tons[0 kW][0 kW]
3 compressors3 compressors
2 compressors2 compressors
1 compressor1 compressor
4 compressors4 compressorsA
B
DC
EF
HG
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Slide Valve
discharge discharge portport
slide valveslide valve
housinghousing
rotorsrotors
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Slide Valve
slide valve(closed)
slide valve
(open)
valvevalveopeningopening
to suctionto suction
full load part load
dischargedischargeportport
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Inlet Vanes
inlet vanesinlet vanes
impellerimpeller
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Inlet Vanes
2525
7575
1010 1414
6363
pres
sure
diff
eren
cepr
essu
re d
iffer
ence
capacitycapacity
surgesurge 9090
3636
5151
A
unloading lineunloading line
vane positionvane position(degrees)(degrees)
CB
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Variable Speed
variable-speedvariable-speeddrivedrive
period three
The Compressor in a System
Refrigeration Compressors
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
System-Level Control
direct expansion (DX)
chilled water
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Constant-Volume DX System
DX coolingDX coolingcoilcoil
thermostatthermostat
supplysupplyfanfan
compressor compressor capacity capacity
controllercontroller
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
supplysupplyfanfan
thermostatthermostat
VAVVAVboxbox
Variable-Air-Volume DX System
DX coolingDX coolingcoilcoil
sensorsensor
compressor compressor capacity capacity
controllercontroller
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Chilled-Water System
pumppump
coilcoilsupplysupply
fanfan
thermostatthermostat
evaporatorevaporatorcompressor compressor capacity controllercapacity controller
modulatingmodulatingwater valvewater valve
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Preventing Evaporator Freeze-Up
suction temperaturesuction temperature
capa
city
capa
city
50°F50°F[10°C][10°C]
40°F40°F[4.4°C][4.4°C]
20°F20°F[-6.7°C][-6.7°C]
30°F30°F[-1.1°C][-1.1°C]
40 tons40 tons[140.7 kW][140.7 kW]
20 tons20 tons[70.3 kW][70.3 kW]
0 tons0 tons[0 kW][0 kW]
3 compressors3 compressors
2 compressors2 compressors
1 compressor1 compressor
4 compressors4 compressorsA
B
DC
EF
HG
freeze-upfreeze-upoccursoccurs
I
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Sensing Suction Temperature
expansionexpansionvalvevalve
evaporatorevaporator
condensercondenser
compressorcompressorsuctionsuction
lineline
sensorsensor
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Hot Gas Bypass to Evaporator Inlet
evaporatorevaporator
condensercondenser
compressorcompressor
hot gas hot gas bypass valvebypass valve
expansion valveexpansion valve
distributordistributor
suction linesuction line
liquid lineliquid line
oil return lineoil return line
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Hot Gas Bypass to Suction Line
evaporatorevaporator
condensercondenser
compressorcompressor
hot gas hot gas bypass valvebypass valve
suction linesuction line
liquid lineliquid line
liquid injection valveliquid injection valve
solenoidsolenoidvalvevalve
period four
Review
Refrigeration Compressors
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Review—Period One
scroll
reciprocating
helical-rotarycentrifugal
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Review—Period Two
Reciprocating Scroll Helical-Rotary Centrifugal
Cylinder Unloaders
Cycle On and Off
Slide Valve
Inlet Vanes
Variable-Speed
Air Conditioning Clinic TRG-TRC004-ENAir Conditioning Clinic TRG-TRC004-EN© American Standard Inc. 2000
Review—Period Three
System-level control Constant-volume DX system
Control by sensing space temperature
VAV DX system Control by sensing supply air temperature
Chilled-water system Control by sensing temperature of water leaving evaporator
Preventing evaporator freeze-up Sensing suction temperature Hot gas bypass