Upload
eustacia-flowers
View
213
Download
0
Embed Size (px)
Citation preview
Transient and equilibrium cycle characteristics on Paks uprated power units with 2nd generation of Gadolinia fuel
Imre NemesPaks NPP Ltd.
Hungary
General status of Paks Units
Non-standard cycles because of incident on Unit 2 2003
Recovery works has finished on Unit 2, unit in operation since 1 January
All units in normal order
108 % ( 1485 MWth, 500 MWe ) evaluated on Unit 4 in 2006 on Unit 1 in 2007
Power uprate in rest of units in next year (2008 )
Actually used fuel
Fixed FA-s : 3.82 wt%, 12.3 mm pitch
Followers : 3.82 wt%, 12.2 mm pitch, 2 mm shroud, Hf layer
90 ( 78+12 ) on 1375 MW units ( 4-year application of fixed assemblies
102 (90+12 ) on 1485 MW units ( poorer fuel cycle economy )
More economic fuel and cycle required
New fuel and cycle - Paks specific requirements
• Economic fuel cycle • High enough reserve in limiting parameters
– Uprated power on units – 1485 MWth, 500 MWe
– Much less reserve in local limits – Limits are untouched :
• Max. assembly power 6.58 – 0.37 MW • Max. pin power 57 - 5.7 kW • Max. linear heat rate 325 – 39 W/cm• Max. subchanel outlet temp. 326 – 7.5 C
– Highly welcome, if parameter is monoton decreasing during cycle
• Moderate increase of max. burnup desired
Gd-2n fuel (for Paks)
Geometry :
Gd-2 fuel
Avg. enr. 4.2 %
Shroud : 1.5 mm
for followers
as well
Some features of this fuel
1.07
1.12
1.17
1.22
1.27
0 5000 10000 15000
Burnup (MWd/tU)
K-i
nf
Gd-3-3.35%
Prof-3.8
1.02
1.03
1.04
1.05
1.06
1.07
1.08
1.09
1.1
0 5000 10000 15000 20000 25000 30000 35000 40000
Burnup (MWd/tU)
kk
-ma
xK-inf vs. burnup curves for Gd-2n and
3.82 % enriched fuel
Max. normalised pin power as a function of burnup for Gd-2n fuel
Method to provide 60 degree core symmetry
SECTOR 1
SECTOR 2
Assembly with odd orientation
Assembly with even orientation
Equilibrium cycle features / 1
Max. calculated burnups :
Assembly 48.9 / 49.5 MWd/kgU
Pin 52.7 MWd/kgU
Pellet 60.1 / 60.6 MWd/kgU
FUEL DESCRIPTION 1ST C. 2ND C. 3RD C. 4TH C. 5TH C. Cycle 31 P 4.20 W 78 12.19 72 25.13 78 37.05 72 44.77 12 46.23Q 4.20 F 6 14.62 12 26.90 6 38.08 12 47.40 0 0.00Y 1.60 F 1 9.39 0 0.00 0 0.00 0 0.00 0 0.00
Cycle 32 P 4.20 W 72 11.98 78 25.32 72 36.93 78 45.03 12 46.64Q 4.20 F 12 14.37 6 26.62 12 38.79 6 44.62 0 0.00Y 1.60 F 0 0.00 1 17.87 0 0.00 0 0.00 0 0.00
Present and expected burnups
Assembly Pin Pellet
Previous limit (MWd/kgU) 49.00 55 64
Actual limit (MWd/kgU) 50.50 56.70 66.00
4.2 % Gd-fuel ,
transient and equilibrium cycles
Max. burnup (MWd/kgU) Assembly Pin Pellet
Calculated maximum 49.5 52.7 60.6
Engineering factor 2.90 5.1 7
Calculated + eng. Factor 52.40 57.80 67.60
Calculated + eng. Factor+reserve 54.00 60 70
Related to previous 1.10 1.09 1.09
Related to new limit 1.07 1.06 1.06
Equilibrium cycle features / 2
1
19.177
2
335.46
3
225.94
4
447.67
5
226.96
6
224.43
7
226.01
8
226.28
9
113.38
10
444.82
11
227.00
12
338.87
13
337.98
14
224.30
15
446.16
16
336.04
17
224.54
18
111.09
19
442.47
20
338.56
21
114.11
22
338.78
23
335.83
24
114.32
25
447.09
26
112.90
27
443.78
28
446.21
29
336.33
30
337.15
31
446.89
32
336.57
33
114.26
34
110.28
35
224.77
36
337.55
37
446.79
38
224.62
39
223.59
40
111.60
41
546.02
42
447.37
43
114.29
44
335.35
45
223.38
46
111.86
47
442.53
48
337.91
49
336.43
50
226.48
51
111.20
52
441.63
53
225.78
54
112.61
55
19.842
56
546.44
57
110.99
58
443.67
59
442.67
Time= 325.00 eff.day
Power= 1485.000 MW
Tin.= 267.000 C
Mod.Flow= 29816.0 t/h
Cb= -0.112 g/kg
Reactivity= 0.0002 %
h6 pos.= 237.000 cm
2 -Ass.pos.
3 -AssAge 38.9 -AssBu[MWd/kgU]
AssAge:
4.78: 5.05
4.51: 4.78
4.24: 4.51
3.97: 4.24
3.70: 3.97
3.43: 3.70
3.16: 3.43
2.88: 3.16
2.61: 2.88
2.34: 2.61
2.07: 2.34
1.80: 2.07
1.53: 1.80
1.26: 1.53
0.99: 1.26
Results of C-PORCA Calculations
Unit=4 Cycle=31
code info:/4/31/GD23/rudas/eoc/-/-
parameters: value: sec: ass.pos: pinpos: layer:
Ass.Pow-max[MW]: 5.510 1 24
Ass.Bu-max[MWd/kgU]: 48.86 1 4
PinPow-max[kW]: 46.18 1 9 16
PinBu-max[MWd/kgU]: 52.71 1 41 35
Tsub-max[C]: 316.5 1 9 43
Nlin-max[W/cm]: 157.7 1 25 71 35
Nlin-limit[W/cm]: 195.2 1 25 71 35
LocPinBu-max[MWd/kgU]: 60.10 1 41 35 16
1
217.48
2
336.30
3
226.40
4
338.42
5
337.98
6
223.39
7
225.97
8
336.51
9
113.10
10
443.53
11
227.18
12
447.21
13
225.99
14
224.50
15
447.25
16
336.10
17
224.46
18
110.96
19
441.91
20
338.78
21
226.17
22
336.54
23
337.43
24
114.06
25
337.97
26
112.80
27
443.29
28
227.36
29
335.58
30
337.27
31
446.32
32
447.21
33
113.98
34
110.15
35
227.45
36
335.11
37
445.79
38
223.94
39
224.18
40
111.37
41
546.54
42
446.67
43
114.14
44
446.15
45
224.80
46
111.70
47
443.71
48
338.54
49
336.37
50
114.06
51
111.39
52
443.80
53
223.30
54
112.89
55
110.19
56
546.75
57
111.00
58
443.66
59
442.47
Time= 325.00 eff.day
Power= 1485.000 MW
Tin.= 267.000 C
Mod.Flow= 29816.0 t/h
Cb= -0.136 g/kg
Reactivity= 0.0002 %
h6 pos.= 237.000 cm
2 -Ass.pos.
4 -AssAge 47.2 -AssBu[MWd/kgU]
AssAge:
4.78: 5.05
4.51: 4.78
4.24: 4.51
3.97: 4.24
3.70: 3.97
3.43: 3.70
3.16: 3.43
2.88: 3.16
2.61: 2.88
2.34: 2.61
2.07: 2.34
1.80: 2.07
1.53: 1.80
1.26: 1.53
0.99: 1.26
Results of C-PORCA Calculations
Unit=4 Cycle=32
code info:/4/32/GD23/rudas/eoc/-/-
parameters: value: sec: ass.pos: pinpos: layer:
Ass.Pow-max[MW]: 5.469 1 43
Ass.Bu-max[MWd/kgU]: 47.25 1 15
PinPow-max[kW]: 45.79 1 43 23
PinBu-max[MWd/kgU]: 52.65 1 56 71
Tsub-max[C]: 316.2 1 43 57
Nlin-max[W/cm]: 155.9 1 15 71 35
Nlin-limit[W/cm]: 192.8 1 15 71 35
LocPinBu-max[MWd/kgU]: 59.84 1 56 71 17
Boron letdown during eq.
cycle
Cycle Data Calculated by C-PORCA Unit=4 Cycle=31
cb_c [g/kg]
teff [FPD]3103002902802702602502402302202102001901801701601501401301201101009080706050403020100
cb_c
[g/
kg]
6
5
4
3
2
1
0
Cycle Data Calculated by C-PORCA Unit=4 Cycle=32
Cycle Lenght= 315.0 eff. day
cb_c [g/kg]
teff [FPD]3103002902802702602502402302202102001901801701601501401301201101009080706050403020100
cb_c
[g/
kg]
6
5
4
3
2
1
0
Max. pin power
during eq. cycle
Cycle Data Calculated by C-PORCA Unit=4 Cycle=31
Pin.p_max [kW]
teff [FPD]3103002902802702602502402302202102001901801701601501401301201101009080706050403020100
Pin.
p_m
ax [
kW]
48
47
46
Cycle Data Calculated by C-PORCA Unit=4 Cycle=32
Cycle Lenght= 315.0 eff. day
Pin.p_max [kW]
teff [FPD]3103002902802702602502402302202102001901801701601501401301201101009080706050403020100
Pin.
p_m
ax [
kW]
48
47
46
Max. linear heat rate during eq.
cycle
Cycle Data Calculated by C-PORCA Unit=4 Cycle=31
Lhr_max [W/cm] Lhr_lim [W/cm]
teff [FPD]3103002902802702602502402302202102001901801701601501401301201101009080706050403020100
Lhr
_lim
[W
/cm
]
285
280
275
270
265
260
255
250
245
240
235
230
225
220
215
210
205
200
Cycle Data Calculated by C-PORCA Unit=4 Cycle=32
Cycle Lenght= 315.0 eff. day
Lhr_max [W/cm] Lhr_lim [W/cm]
teff [FPD]3103002902802702602502402302202102001901801701601501401301201101009080706050403020100
Lhr
_lim
[W
/cm
]
260
255
250
245
240
235
230
225
220
215
210
Max. subchanel
outlet temp. during eq.
cycle
Cycle Data Calculated by C-PORCA Unit=4 Cycle=31
t_sub_max [C]
teff [FPD]3103002902802702602502402302202102001901801701601501401301201101009080706050403020100
t_su
b_m
ax [
C]
321
320
319
318
317
316
315
314
Cycle Data Calculated by C-PORCA Unit=4 Cycle=32
Cycle Lenght= 315.0 eff. day
t_sub_max [C]
teff [FPD]3103002902802702602502402302202102001901801701601501401301201101009080706050403020100
t_su
b_m
ax [
C]
321
320
319
318
317
316
315
314
(quasy) LTA program
• Goal : test fuel assembly outlet temperature ( measured vs. predicted )
• Finalise the model of outlet temperature measurement taking into accout coolant mixing features in assembly head
• Measure importance of follower containing Gd burnable poisson, compare to predicted
• Tool : 18 quasy LTA to Unit 4 of Paks , 12 fixed, 6 follower assemblies
Core arraengement
for LTA program
Gd fuel on positions :
18, 55 ( fixed )
33 (followers )
1
10980.879
2
10111.214
3
10111.081
4
10131.138
5
10111.167
6
10110.994
7
10130.980
8
10111.021
9
10111.197
10
10130.592
11
10111.222
12
10111.202
13
10111.039
14
10111.007
15
10111.128
16
10111.131
17
10111.124
18
10141.033
19
10110.353
20
10111.079
21
10111.194
22
10111.127
23
10111.112
24
10111.291
25
10111.008
26
10111.176
27
10110.747
28
10111.200
29
10111.007
30
10130.979
31
10110.966
32
10110.993
33
10151.255
34
10110.913
35
10111.164
36
10111.125
37
10110.988
38
10110.988
39
10111.285
40
10110.902
41
10110.343
42
10111.131
43
10111.297
44
10111.019
45
10111.320
46
10111.063
47
10110.399
48
10111.038
49
10111.035
50
10131.243
51
10111.038
52
10110.424
53
10111.297
54
10111.172
55
10140.914
56
10110.346
57
10111.004
58
10110.487
59
10110.327
Time= 0.00 eff.day
Power= 1485.000 MW
Tin.= 267.000 C
Mod.Flow= 29816.0 t/h
Cb= 7.283 g/kg
Reactivity= 0.0008 %
h6 pos.= 212.000 cm
2 -Ass.pos.
1011 -AssType 1.2 -Kq
AssType:
2.4 %-tk-Zr-1.22-F
3.82%-tn-Zr-1.23-W
3.82%-tk-Zr-1.22-F-Hf
4.2 %-tn-Zr-1.23-W-HU-Gd
4.2 %-tk-Zr-1.23-F-Hf-HU_Gd
Results of C-PORCA Calculations
Unit=4 Cycle=23
code info:/4/23/GD23/boros/0&0/-/-
parameters: value: sec: ass.pos: pinpos: layer:
Ass.Pow-max[MW]: 5.616 1 45
Ass.Bu-max[MWd/kgU]: 39.10 1 56
PinPow-max[kW]: 48.20 1 33 3
PinBu-max[MWd/kgU]: 41.50 1 56 71
Tsub-max[C]: 317.4 1 45 245
Nlin-max[W/cm]: 253.1 1 33 3 19
Nlin-limit[W/cm]: 286.0 1 33 3 19
LocPinBu-max[MWd/kgU]: 48.23 1 56 104 17Cycle 23 FUEL DESCRIPTION 1ST C. 2ND C. 3RD C. 4TH C. 5TH C. K 3.82 W 78 12.76 90 25.79 90 37.85 42 40.90 0 0.00 M 3.82 F 6 14.20 12 26.73 12 33.48 0 0.00 0 0.00 P 4.20 W 12 10.73 0 0.00 0 0.00 0 0.00 0 0.00 Q 4.20 F 6 14.33 0 0.00 0 0.00 0 0.00 0 0.00 X 2.40 F 0 0.00 1 22.49 0 0.00 0 0.00 0 0.00
Conclusions
• Gd – 2n fuel is seemed to satisfy Paks specific requirements
• Equilibrium cycle is determined • Limiting parameters show relatively low
value and monoton decreasing feature• Max burnup is 6-7 % higher then the
present one
• Reload for application of quasy LTA-s is prepared
Calculation codes
• Methodical calculations and CCS libraries : HELIOS 1.9
• Core calculations : C-PORCA 6.2– Number of axial layers : 41 for old 42
for new fuel