2007年 8月 - oak.chosun.ac.kr

Microsoft Word - 001.docCharacteristics in Refrigeration using NH3 and HFC-134a
2007 8

.
2007 4

- i -
2.2 (NH3, R717) 7
2.3 HFC-134a 10
2.4 12
2.4.1 12
2.4.2 14
5.2 31
5.3 35
5.4 39
5.5 COP 43
: Cooling Water Temperature of Condenser []
: Chilled Water Temperature of Evaporator []
: Enthalpy [ ]
Table 2 Recommended properties for an alternative refrigerant 6
Table 3 The effect of the refrigerants on the environment 9
Table 4 Equipment specification of refrigereration
system for experimental 21
- v -
List of Figures
Fig. 1 P-h Diagrams of the theoretical and actual refrigeration cycles. 15
Fig. 2 The schematic diagrams of refrigeration system. 20
Fig. 3 The relations of suction mass flow rate and
superheat temperature at each condensing pressure. 28
Fig. 4 The relations of suction pressure and superheat temperature at
each condensing pressure. 30
Fig. 5 The relations of cooling water mass flow rate and
Fig. 6 The relations of cooling water outlet temperature and superheat
temperature at each condensing pressure. 34
Fig. 7 The relations of condenser heat capacity and
Fig. 8 The relations of power and superheat temperature at
Fig. 9 The relations of chilled water outlet temperature and superheat
temperature at each condensing pressure. 40
Fig. 10 The relations of evaporator heat capacity and
Fig. 11 The relations of COP and superheat temperature at
- vii -
ABSTRACT
Characteristics in Refrigeration using NH3 and HFC-134a
Nowadays CFC refrigerants has been restricted because it cause
destruction of an ozone layer and global warming. In this aspect of
environmental problem, the best solution is to use the natural refrigerant in
the world such as ammonia of mineral compounds and propane, propylene
of hydrocarbon. The natural refrigerants easy and cheap to obtain as well
as environmental.
Therefore, this experiment apply the NH3 and HFC-134a to the study of
performance characteristic though the superheat control and compare the
energy efficiency of two refrigerants from the high performance.
The result of performance characteristic test according to condensing
pressure and superheat temperature is as following.
1. As the mass flow rate, NH3 has steady than HFC-134a in condensing
pressure and superheat temperature. Also NH3 was operated double the
Jae-Geun Kim
Graduate School of Education, Chosun University
- viii -
decreased.
As the result, NH3 will apply to a small size refrigerating system than
HFC-134a.
2. As the condensing pressure was raised, the COP was decreased due to
increase of compression rate and power.
3. The COP of the was refrigerant NH3 was higher than HFC-134a, in case
of NH3, the most suitable operating when the superheat temperature 1
at each condensing pressure.
4. If NH3 applies to the HFC-134a refrigerating system in the field of
industry, it is posible to have economic profit and to solve the
environment problem.
Therefore, the NH3 is suitable as the alternative refrigerant of the
HFC-134a.
- 1 -
20 , CFC
.
CFC
. 1)
,
,
. 2)

,
.
NH3, , ,
, ,
. NH3
. 3)
NH3
.
.
NH3 . 4)
HFC-134a ,
(Cl) (H)
(Ozone Depletion Potential, ODP) 0 1994
, , ,
- 2 -
.
, ,
, ,
HFC-134a .
NH3 HFC-134a
NH3
HFC-134a .

,
,
.
Table 1 .
,
,

.
.

.

(COP)
(ODP) 0 ,
(GWP) .
CFC .
CFC

.5,6) Table 2 .
- 4 -
2.1.1.1

2.1.1.3

,

- 5 -
Table Table Table Table 1 1 1 1 Characteristics Characteristics Characteristics Characteristics of of of of refrigerantrefrigerantrefrigerantrefrigerant
Refrigerant
ASHRAE SAFETY GROUP B2 A3 A1 A1/A1
TC/TE
40/0
TC/TE
40/-20
Psat(bar)
The theoretical refrigeration cycle and saturated properties are based on
the NIST REFPROP ver.6.0.
- 6 -
Table Table Table Table 2 2 2 2 The The The The effect effect effect effect of of of of the the the the refrigerants refrigerants refrigerants refrigerants on on on on the the the the environmentenvironmentenvironmentenvironment
Refrigerant ODP GWP
2.2 (NH3, R717)
, ,
.

,
.
, CFC/HCFC
. 7)

, , , .
TWA(Time weight average concentration)
STEL(Short term exposure limit) , TWA 8, STEL
15 . TWA STEL
. 8,9)

.
1:1 . Table 3 134a
.
.
.

.
- 8 -
.
.
- 9 -
Table Table Table Table 3 3 3 3 General General General General data data data data of of of of Ammonia Ammonia Ammonia Ammonia compared compared compared compared with with with with HFC-134aHFC-134aHFC-134aHFC-134a
Characteristics Ammonia HFC-134a HCFC-22
Molecular Weight (/kmol) 17.03 102.031 86.48
Ozone depletion potential 0 0 0
Global warming potential(100 year) 0 1300 1700
Normal boiling point at 1.013 bar () -33.3 -26.06 -40.6
Critical pressure (bar) 113.3 40.65 49.9
Critical temperature () 132.3 101.08 96.2
Enthalpy of evaporation at 0 (kJ/) 1261.7 198.6 204.9
Specific heat of sat. liq. at 0 (kJ/K) 4.62 0.98 1.17
Specific heat of sat. vap. at 0 (kJ/K) 2.66 0.8518 0.74
Thermal conductivity of sat. liq.
at 0 (W/m K) 0.520 0.0796 0.096
Thermal conductivity of sat. vap.
at 0 (W/m K) 0.022 0.0134 0.010
Dynamic viscosity of sat. liq.
at 0 (10-6Pas) 175.8 201.9 210.1
Dynamic viscosity of sat. vap.
at 0 (10-6Pas) 9.09 12.41 11.8
Density of sat. liq. at 0 (/) 638.6 1206.0 1281.8
Density of sat. vap. at 0 (/) 0.289 32.249 0.047
Flammable or explosive? Yes No No
Toxic/irritating decomposition No No Yes
Approximate relative price 0.2 - -
2.3 HFC-134a(CH2F-CF33, 134a)
(Cl) CFC HCFC
, (Cl) (H)
(Ozone Depletion Potential, ODP) 0
(R-12) HFC-134a , 1989
.
HFC-134a HCFC-22, CFC-12
, ,
HCFC-22 CFC-12 HCFC-22
.
HFC-134a Table 3
NH3 HFC-134a . HFC-134a

(GWP)
. HFC-134a .

(ODP) 0
.
.
.

ASME Code .
- 11 -

.
.
- 12 -
. (1)
. (2),
. (3)
.
P-h Fig. 1 ,
.
( Wc )
.
( Qc )
- 13 -
, Cp , cw , θ1,θ2
, K , F , Δtm .
3→4 : h3 h4 , s3<s4
.
( Qe )
KFΔtm (4c)
, Cp , ew , θ3,θ4
, K , F , Δtm .
h1-h4 (RE : Refrigerating Effect) ,
(Coefficient of Performance) .
COP (5)
Qe
Wc
- 14 -
2.4.2

. Fig. 1 P-h ,
.
A→B :

,
.
D→E :
.
E→F :
,
.
G→H :

. ,
,
H→I :
. ,
,
- 15 -
I→J :
. hJ = hI
hJ > hI .
J→K : .
K→L :
.
L→M :
.
M→A :
.
- 16 -
Fig. Fig. Fig. Fig. 1 1 1 1 P-h P-h P-h P-h Diagrams Diagrams Diagrams Diagrams of of of of the the the the theoretical theoretical theoretical theoretical and and and and actual actual actual actual refrigeration refrigeration refrigeration refrigeration cycles.cycles.cycles.cycles.
AAAA BBBB
Photo.1 Fig. 2
.
HFC-134a
Table-4 , , , ,
.
, ,
, . ,
,
. , ,
. 10)

, KS
.
, , , , ,
, ( ±0.1, ±0.1kPa, ±0.1%,
±0.1%) .
,
.
8, 4 Shell & Tube Type
, .
1kW 3-way
.

- 18 -

PID
11,12)
.

,
. ,
13)
.
- 19 -
Photo. Photo. Photo. Photo. 1 1 1 1 Photograph Photograph Photograph Photograph of of of of the the the the experimental experimental experimental experimental apparatusapparatusapparatusapparatus
- 20 -
Fig. Fig. Fig. Fig. 2 2 2 2 The The The The schematic schematic schematic schematic diagrams diagrams diagrams diagrams of of of of refrigeration refrigeration refrigeration refrigeration system.system.system.system.
1 : Compressor 2 : Oil separator 1 : Compressor 2 : Oil separator 1 : Compressor 2 : Oil separator 1 : Compressor 2 : Oil separator 3 : Condenser 3 : Condenser 3 : Condenser 3 : Condenser
4 : Receiver 5 : Expansion valve 4 : Receiver 5 : Expansion valve 4 : Receiver 5 : Expansion valve 4 : Receiver 5 : Expansion valve 6 : Evaporator6 : Evaporator6 : Evaporator6 : Evaporator
7 : Constant temperature bath 7 : Constant temperature bath 7 : Constant temperature bath 7 : Constant temperature bath 8, 9 : Circulation pump 8, 9 : Circulation pump 8, 9 : Circulation pump 8, 9 : Circulation pump
P : Pressure sensor T : TemperatP : Pressure sensor T : TemperatP : Pressure sensor T : TemperatP : Pressure sensor T : Temperature sensorure sensorure sensorure sensor
PCV : Pressure control valve SHV : SuperheatPCV : Pressure control valve SHV : SuperheatPCV : Pressure control valve SHV : SuperheatPCV : Pressure control valve SHV : Superheat controllercontrollercontrollercontroller
F : Mass flow meter PM : Power mF : Mass flow meter PM : Power mF : Mass flow meter PM : Power mF : Mass flow meter PM : Power metereteretereter
: Refrigerant :: Refrigerant :: Refrigerant :: Refrigerant : Cooling & Chilled waterCooling & Chilled waterCooling & Chilled waterCooling & Chilled water
SHVSHVSHVSHV
Digital control systemDigital control systemDigital control systemDigital control system
ControllerControllerControllerController
PLCPLCPLCPLC
SHVSHVSHVSHV
Digital control systemDigital control systemDigital control systemDigital control system
ControllerControllerControllerController
PLCPLCPLCPLC
- 21 -
EquipmentEquipmentEquipmentEquipment MODEL MODEL MODEL MODEL & & & & TYPETYPETYPETYPE specificationspecificationspecificationspecification
CompressorCompressorCompressorCompressor Screw Screw Screw Screw / / / / OpenOpenOpenOpen 118 118 118 118 /h/h/h/h
Main Main Main Main motermotermotermoter TEFCTEFCTEFCTEFC 15 15 15 15 kWkWkWkW
Oil Oil Oil Oil coolercoolercoolercooler Shell Shell Shell Shell and and and and TubeTubeTubeTube 7.0 7.0 7.0 7.0
CondenserCondenserCondenserCondenser Shell Shell Shell Shell and and and and TubeTubeTubeTube 8.0 8.0 8.0 8.0
Evaporator Evaporator Evaporator Evaporator withwithwithwith
knock knock knock knock out out out out drumdrumdrumdrum Shell Shell Shell Shell and and and and TubeTubeTubeTube 4.0 4.0 4.0 4.0
Bath Bath Bath Bath tanktanktanktank RectangleRectangleRectangleRectangle 1 1 1 1
- 22 -
, ,
18/
, 24
.

.
400mmHg 10
. Solkatronic
Chemical 99.999% ISO VG
46 .
.
Table 5 .

. 1500 kPa 1600 kPa 50 kPa
.

.
- 23 -

.
0~5 1
30
.
, .
System
Computer Digital
.
(Hook meter) (R,S,T)
, Tester
. Digital Analog
Tester Analog Digital
.
, 1
.

.
Oval Type
.
.

- 24 -
, , T-Type
Thermo Couple . Data
Acquisition System 2 Computer
.
Computer 3 .
- 25 -
Table Table Table Table 5 5 5 5 Experimental Experimental Experimental Experimental conditionconditionconditioncondition
Parameter Experimental condition
Cooling & Chilled water Demineralized
, ,
, , ,
COP
.
Fig. 3 .
NH3 HFC-134a HFC-134a
, NH3
.
NH3 1
, 0 ,

14,15)
.
HFC-134a 0 2
1500 kPa 1550 kPa ,
,
.

.

.
- 27 -
HFC-134a NH3 ,
NH3 HFC-134a HFC-134a
NH3
0000 1111 2222 3333 4444 5555
Degree of superheat ()Degree of superheat ()Degree of superheat ()Degree of superheat ()
m r( k g / h )
m r( k g / h )
m r( k g / h )
m r( k g / h )
R717:1500(kPa)R717:1500(kPa)R717:1500(kPa)R717:1500(kPa) R717:1550(kPa)R717:1550(kPa)R717:1550(kPa)R717:1550(kPa) R717:1600(kPa)R717:1600(kPa)R717:1600(kPa)R717:1600(kPa)
134a:1500(kPa)134a:1500(kPa)134a:1500(kPa)134a:1500(kPa) 134a:1550(kPa)134a:1550(kPa)134a:1550(kPa)134a:1550(kPa) 134a:1600(kPa)134a:1600(kPa)134a:1600(kPa)134a:1600(kPa)
Fig. Fig. Fig. Fig. 3 3 3 3 The The The The relation relation relation relation of of of of suction suction suction suction mass mass mass mass flow flow flow flow rate rate rate rate and and and and superheat superheat superheat superheat temperature temperature temperature temperature at at at at
each each each each condensing condensing condensing condensing pressurepressurepressurepressure
- 29 -
NH3 HFC-134a

.
, NH3 1
0 17,18) .
5 1500 kPa ~ 1600 kPa
. HFC-134a
.

. 4 1500 kPa ~ 1600 kPa
.

.
NH3
,
HFC-134a
.
- 30 -
5555
6666
7777
8888
0000 1111 2222 3333 4444 5555
PP PP ss ss (b
a r)
Fig. Fig. Fig. Fig. 4 4 4 4 The The The The relation relation relation relation of of of of suction suction suction suction pressure pressure pressure pressure and and and and superheat superheat superheat superheat temperature temperature temperature temperature at at at at each each each each
condensing condensing condensing condensing pressurepressurepressurepressure
- 31 -
Fig. 5 .
NH3 HFC-134a
,
.
NH3 1
0~2
, 0
14,15)
. HFC-134a

.
NH3 HFC-134a
, HFC-134a
.
HFC-134a NH3 ,
NH3 HFC-134a .
- 32 -
0000
1000100010001000
2000200020002000
3000300030003000
4000400040004000
5000500050005000
6000600060006000
7000700070007000
8000800080008000
0000 1111 2222 3333 4444 5555
mm mm c w
R717:1500(kPa)R717:1500(kPa)R717:1500(kPa)R717:1500(kPa) R717:1550(kPa)R717:1550(kPa)R717:1550(kPa)R717:1550(kPa) R717:1600(kPa)R717:1600(kPa)R717:1600(kPa)R717:1600(kPa) 134a:1500(kPa)134a:1500(kPa)134a:1500(kPa)134a:1500(kPa) 134a:1550(kPa)134a:1550(kPa)134a:1550(kPa)134a:1550(kPa) 134a:1600(kPa)134a:1600(kPa)134a:1600(kPa)134a:1600(kPa)
Fig. Fig. Fig. Fig. 5 5 5 5 The The The The relations relations relations relations of of of of cooling cooling cooling cooling water water water water mass mass mass mass flow flow flow flow rate rate rate rate and and and and superheat superheat superheat superheat
temperature temperature temperature temperature at at at at each each each each condensing condensing condensing condensing pressure pressure pressure pressure
- 33 -
NH3 HFC-134a
.

NH3 HFC-134a
NH3 1 1500 kPa
HFC-134a 1500 kPa .

1

.
- 34 -
30303030
35353535
40404040
45454545
0000 1111 2222 3333 4444 5555
T c w (
) T c w (
) T c w (
) T c w (
R717:1500(kPa)R717:1500(kPa)R717:1500(kPa)R717:1500(kPa) R717:1550(kPa)R717:1550(kPa)R717:1550(kPa)R717:1550(kPa) R717:1600(kPa)R717:1600(kPa)R717:1600(kPa)R717:1600(kPa) 134a:1500(kPa)134a:1500(kPa)134a:1500(kPa)134a:1500(kPa) 134a:1550(kPa)134a:1550(kPa)134a:1550(kPa)134a:1550(kPa) 134a1600(kPa)134a1600(kPa)134a1600(kPa)134a1600(kPa)
Fig. Fig. Fig. Fig. 6 6 6 6 The The The The relations relations relations relations of of of of cooling cooling cooling cooling water water water water outlet outlet outlet outlet temperature temperature temperature temperature and and and and superheat superheat superheat superheat
- 35 -
NH3 HFC-134a
.
.
NH3 HFC-134a 20kW
. NH3
0 14,15)
1
HFC-134a 0
.

.
,
.
, ,

.
.
0000 1111 2222 3333 4444 5555
Q c (k W )
Q c (k W )
Q c (k W )
Q c (k W )
Fig. Fig. Fig. Fig. 7 7 7 7 The The The The relations relations relations relations of of of of condenser condenser condenser condenser heat heat heat heat capacity capacity capacity capacity and and and and superheat superheat superheat superheat temperature temperature temperature temperature
at at at at each each each each condensing condensing condensing condensing pressure pressure pressure pressure
- 37 -
.
NH3 HFC-134a
0 .

,
.
.
0000 1111 2222 3333 4444 5555
P o w e r( k W )
P o w e r( k W )
P o w e r( k W )
P o w e r( k W )
R717:1500(kPa)R717:1500(kPa)R717:1500(kPa)R717:1500(kPa) R717:1550(kPa)R717:1550(kPa)R717:1550(kPa)R717:1550(kPa) R717:1600(kPa)R717:1600(kPa)R717:1600(kPa)R717:1600(kPa) 134a:15009kPa134a:15009kPa134a:15009kPa134a:15009kPa 134a:1550(kPa)134a:1550(kPa)134a:1550(kPa)134a:1550(kPa) 134a:1600(kPa)134a:1600(kPa)134a:1600(kPa)134a:1600(kPa)
Fig. Fig. Fig. Fig. 8 8 8 8 The The The The relations relations relations relations of of of of power power power power and and and and superheat superheat superheat superheat temperature temperature temperature temperature at at at at each each each each
condensing condensing condensing condensing pressure pressure pressure pressure
- 39 -
Fig.9 .

.
NH3 1
.
HFC-134a 0 ,
4~5 1500 kPa
1600 kPa .
NH3 HFC-134a

.
,
.
.
- 40 -
22222222
23232323
24242424
25252525
26262626
0000 1111 2222 3333 4444 5555
T c h (
) T c h (
) T c h (
) T c h (
Fig. Fig. Fig. Fig. 9 9 9 9 The The The The relations relations relations relations of of of of chilled chilled chilled chilled water water water water outler outler outler outler temperature temperature temperature temperature and and and and superheat superheat superheat superheat
- 41 -

.
NH3 1
HFC-134a 0
.

.
,
.

.
0000 1111 2222 3333 4444 5555
Q e (k W )
Q e (k W )
Q e (k W )
Q e (k W )
Fig. Fig. Fig. Fig. 10 10 10 10 The The The The relations relations relations relations of of of of evaporator evaporator evaporator evaporator heat heat heat heat capacity capacity capacity capacity and and and and superheat superheat superheat superheat
temperaturetemperaturetemperaturetemperature at at at at each each each each condensing condensing condensing condensing pressure pressure pressure pressure
- 43 -
COP .
,
.
,
. NH3 0 1 14,15)

NH3 .
, NH3 HFC-134a
COP . NH3
HFC-134a COP . NH3
COP .
- 44 -
1111
2222
3333
4444
5555
0000 1111 2222 3333 4444 5555
C O P
C O P
C O P
C O P
Fig. Fig. Fig. Fig. 11 11 11 11 The The The The relations relations relations relations of of of of COP COP COP COP and and and and superheat superheat superheat superheat temperature temperature temperature temperature at at at at each each each each
condensing condensing condensing condensing pressure pressure pressure pressure
- 45 -
6
HFC-134a NH3
.
1. NH3 HFC-134a
, NH3 HFC-134a 2
1/4 . , NH3
HFC-134a .
2.
COP .
3. COP NH3 HFC-134a .
NH3 ,
. NH3 , 1
.
4. NH3
HFC-134a ,
,
, HFC-134a .
- 46 -

1) Stoecker, W, F., Refrigeration and Air conditioning, 2nd ed., New York:
McGraw-Hill, 1982, pp296-307.
2) Nonaka, M. et al., Performance and reliability of room Air conditioner
using R410A, The Int. Symp. on HCFC Alternative Refrigerants, 1998,
pp111-116.
3) Han, J. S. Youn, J. G. and Won, S. P.. "A study on performance
characteristic of new alternative refrigerant replacing HFC-134a". The
Society of Air conditioning and Refrigerating Engineers of Korea.
Proceedings of the SAREK '99 Summer Annual Conference() :
pp219-224, 1999.
4) Mclinden, M.. Klein, S.. lemmin, E.. and Peskin, A.. NIST Thermodynamic
and Transport Properties of Refrigerants and Refrigerant Mixtures(REFP.)
Version 6.0 : National Institute of Standards and Technology, 1998.
5) Altunin, V. V. et al.. Thermophysical Properties of Freons, Methane
Series, Part 2, National Standard Reference Data Service of the USSR :
A Series of Property Tables., Vol. 9 : Hemisphere Pub. Corp., 1987,
pp70.
6) Bullard, C.W. and Radermacher, R.. "New Technologies for Air
conditioning and Refrigeration" Annu. Rev. Energy Environ. 19 :
pp113-152, 1994.
7) , , Vol. 3, 2001, pp.1.2-23.
8) FuKushima, M., T. Kaminura and N. Watanabe. Preprint of the 30th High
Pressure Conference of Japan, 1989, pp350.
- 47 -
9) JSME. "Thermophysical Properties of Fluids, Japan Soc. of Mech. Enger."
JSME Data Book : 326, 1982.
10) Yun, J. I.. Refrigerating Engineering, Seoul : Munundang, 1998,
pp29-30.
11) Higuchi, K.. Electronic expansion valve and control, Refrigeration, Vol.
61, 1986, pp45-52.
13) ASHRAE, Refrigeration systems and application." ASHRAE handbook,
1994.
14) W., Front. G., S. Dzakowic. An extension of the method of predicting
incipient boiling on commercially finished surfaces : ASME/AIChe Heat
Transfer Conference, paper 67-ht-61, 1967, pp.1-8.
15) A.E. Bergles and W.M. Rohsenow. "The determination of
forced-convection surface-boiling heat tranfer." Journal of Heat
Transfer 86C : 365~372, 1964.
- 48 -

.
3 12
.
, , ,
, .

, , ,
, .
, ,
, , ,
.

,
, ,
.

,
, .
.
2007 8
- 49 -

20048212
: : : Jae-Geun kim
@ 202-1803
E-MAIL: [email protected]
: The Study on Comparison of Performance Characteristics
in Refrigeration using NH3 and HFC-134a

.
- -
1. DB ,
,
2. .
, .
3. , , .
4. 5 , 3
.
5. 1
.
6.

7.
.

2.3 HFC-134a(CHF-CF3, 134a)
2.4
2.4.1
2.4.2
5.1
5.2
5.3
5.5 (COP)

2007年 8月 - oak.chosun.ac.kr

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