System and Component Efficiency with Refrigerant R410a A. T. Setiawan 1, A. Olsson 2, H. Hager 2 1 Department of Energy Technology, Div. Of Applied Thermodynamics.
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System and Component Efficiency System and Component Efficiency with Refrigerant R410awith Refrigerant R410a
A. T. Setiawan1, A. Olsson2, H. Hager2
1Department of Energy Technology, Div. Of Applied Thermodynamics and Refrigeration, KTH, Stockholm
2SWEP International AB, Box 105, SE-261 22 Landskrona,
Sweden
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Properties of R410A
Comparison with other common refrigerants
System characteristics
Experimental test facility
Experimental heat transfer results
Comparison to other data and other refrigerants
Overview
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
R410a
Properties
50/50 mixture of R32/R125 (CH2F2 – C2HF5)
Glide : Less than 0,1°C (azeotropic)
Comparably high pressure (15 Bars at Tamb)
ODP : 0 % (HFC refrigerant)
GWP : 1730 (compared to CO2)
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
R410a
Vapor Pressure curve
0
5
10
15
20
25
30
35
40
45
-20 0 20 40 60 80
Temperature (ºC)
Vap
our
pres
sure
(ba
r)
R22 R407c R410a R134a R290
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
COP2, comparison of refrigerants (T1=40°C)
1
2
3
4
5
6
7
8
-20 -15 -10 -5 0 5 10
Evaporation temperature (°C)
CO
P 2
R410A
R134a
R407C
R290
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Pressure ratio, comparison of refrigerants (T1=40°C)
0
1
2
3
4
5
6
7
8
-20 -10 0 10 20
Evaporation temp (°C)
R410A
R134a
R407C
R290
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
R410a
Pro’s and Con’s
Pro’s Con’s
•Low specific volume, lead to smaller piping and other components•No glide (0.1K)•No ODP (Ozone Depleting Potential)•Appropriate for new systems
•High pressure, need special components•GWP (Global Warming Potential)•Not appropriate when converting old R22 systems•Low critical temperature (73ºC), limiting the condensation temperature.
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Figures of Merit Evaporation in horizontal tubes
5,1
25,0
8,04,0
".
.
fg
EDP
fg
E
h
vFOM
h
kFOM
23
41
419
43
47
54
52
52
59
54
52
54
"...
..
1401,0
fg
m
fg
h
vx
d
LQCp
h
k
Ld
Q
g
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Figures of Merit
Evaporator (examples)
0
0.5
1
1.5
2
-15 -10 -5 0 5 10 15
Temperature (ºC)
FO
M E
R407c R410a R134a Propane
O.Pelletier, 2003
0
0.5
1
1.5
2
-15 -10 -5 0 5 10 15
Temperature (ºC)
FO
M ED
P
R407c R410a R134a Propane
O.Pelletier, 2003
Boiling Heat Transfer
Evaporator Pressure Drop
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
SSP–CBE Modelling
Relative CBE size, chiller mode
Evaporator Chiller Mode: t2=2 ºC (4 ºC), dtS H=4 K, x IN=0.2, dtW =5 K, dpW =35 kPa
0
0.2
0.4
0.6
0.8
1
1.2
1.4
B15 V80 V200
NoP
/No
PR
22 R22
R134a
R410A
R407C
Condenser Chiller Mode: t1=40 ºC, dtSC=2 K, tD SH=70 ºC, dtW =5 K, dpW =35 kPa
0
0.2
0.4
0.6
0.8
1
1.2
B15 B25 B45
NoP
/No
PR
22 R22
R134a
R410A
R407C
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
SSP–CBE Modelling
Relative CBE size, heat pumpEvaporator Heat pump Mode: t2=-7 ºC (-5 ºC), dtSH=4 K, x IN=0.25, dtB=3 K, dpB=50 kPa
0
0.2
0.4
0.6
0.8
1
1.2
1.4
B15 V80 V200
No
P/N
oP
R2
2 R22
R134a
R410A
R407C
Condenser Heat pump Mode: t1=55 ºC, dtSC=2 K, tDSH=90 ºC, dtW =10 K, dpW =50 kPa
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
B15 B25 B45
No
P/N
oP
R22 R22
R134a
R410A
R407C
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Experimental Test Facility
Availability of components
Hermetic compressors available (?) up to 150 kW cooling (tandem)
Expansion valve : Limited availability
Copper tubes up to 12 mm, then steel
Sight glass, filter-dryer, valves available
Check valve, oil separator, limited
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Experimental Test Facility Tested heat exchangers
Condenser : Plate heat exchanger (CBE), 34 plates, 2.0 m2
co-current and counter-current
Evaporator : Plate heat exchanger (CBE), 34 plates, 2.0 m2
Plate heat exchanger (CBE), 32 plates, 1.0 m2
both counter-current
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Experimental Test Facility Schematic view
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Experimental Test Facility The Refrigerant loop, schematic
Filter Dryer
+ Sight Glass
SubCooler
Liquid separator
Receiver Tank
OIL separator
Bypass line (changing CBEs) emptying condenser and evaporator
Condenser
Evaporator
Bypass line (changing CBEs) pushing refrigerant into receiver tank
Parallel Scroll
Compressor
Massflow Meter
Expansion Valve
Oil Return Line
3
2
1
5 4 Normal Operation Valve 1, 2, 3 OPEN Valve 4, 5 CLOSE Changing CBEs (collecting refrigerant in Receiver Tank) Valve 1, 2, 3 CLOSE Valve 4 ,5 OPEN SubCooler acting as condenser
for refrigerant storage
LP
Safety switch (electronic)
HP Safety switch (electronic)
Oil Level Sensor
(electronic)
Oil Return Valve
Safety Valve
Capillary Line
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Evaporator test
Operational conditions
Evaporation temp : 2°C
Inlet vapor quality : 20%
TSuperheat = 4°C
Heat flux range : 8 – 15 kW/m2
TBrine = 5°C
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Evaporator test
Different CBE size
0
500
1000
1500
2000
2500
3000
7 8 9 10 11 12 13 14 15 16 17 18
Heat Flux (kW/m²)
U (
W/m
².K
)
Large CBESmall CBE
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Condenser test
Operational conditions
Condensing temp : 40°C
Compressor discharge temp : 75°C
No subcooling
Heat flux range : 9 – 18 kW/m2
TBrine = 5°C
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Condenser test
Different flow direction
0
500
1000
1500
2000
2500
3000
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
Heat Flux (kW/m²)
U (
W/m
².K
)
cocurrentcounterflow
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Evaporator test
Comparison with literature data
0
500
1000
1500
2000
2500
3000
7 8 9 10 11 12 13 14 15 16 17 18
Heat Flux (kW/m²)
U (
W/m
².K
)
Large CBE (R410a) Small CBE (R410a) comheta B (R410a)
comheta B (R134a) comheta B (R407c) comheta B (R22)
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
Condenser test
Comparison with literature data
0
500
1000
1500
2000
2500
3000
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
Heat Flux (kW/m²)
U (
W/m
².K
)
cocurrent counterflow comheta B
comheta B (R134a) comheta B (R407c) comheta B (R22)
(R410A)
Div. of Applied Thermodynamics and Refrigeration Department of Energy TechnologyRoyal Institute of Technology, Stockholm
For more information, please refer to final report.
Thank you for your attention
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