RRFM 2009 Transactions - European Nuclear Society

More documents

Recommendations

Info

3.2 Strain limit The value of 3.65% retained by CEA for the strain limit is issued from several dynamic tensile tests performed on clad rings at several temperatures (20°C to 1100°C) and having provided values for the total elongation. These tests gave also yield strength and tensile strength values. The strain rate was about 100%.s -1 (i.e 1% for 10 ms) and was representative of the phenomena kinetics occurring during fast reactivity insertion transients. The strain limit of 3.65% is one half of the minimum value of the rupture elongation measured during all the tests. IRSN raised the following questions in concern with the choice of the strain limit: Choice of the strain limit as a function of the rupture elongation IRSN said that the choice of a rupture criterion based on the total elongation is valid for secondary loads. During the transient, the strain is imposed during the PCMI phase but not after the pellet-to-clad gap re-opening. For this latter case, CEA answered that the load is an imposed pressure. However, because of the clad strain, the pressure decreases with time. It was further showed that this loading situation is less severe than an imposed strain. IRSN agreed and considered that loads resulting from the ‘imposed strain’ type are the enveloping situation for the clad loads during the transient thus justifying the use of the total strain as a limit. Bi-axiality of the stresses IRSN examined the representativeness of the tests made on the clad rings with regard to the bi-axiality of the stresses as this point can modify the value of the rupture elongation. During the PCMI phase, the ratio between the two components of the clad deformation (ε z and ε θ ) is positive while this ratio is negative for the tests made on the clad rings. This effect is important for rods with a high burn-up for which clad and fuel pellets are “ stuck “ or when the cladding material is a zirconium alloy which anisotropy may lead to a large reduction of the rupture elongation [1]. As the CABRI core rods have a very low burn-up (about 100 MWd/t) and are made of stainless steel having an isotropic behaviour, IRSN considers that the factor 2 used to assess the clad strain limit is sufficient to account for the effects of bi-axiality. Risks of damage related to cyclic loadings IRSN considered that the damage related to cyclic loadings was not considered. Afterwards CEA provided a study coupling the primary loads (in relation with internal rod pressure) and the secondary loads (in relation with the thermal gradient in the clad thickness) for several cycles (for CABRI, one cycle corresponds to one fast transient). These load combinations were studied by Bree [2] who provided a diagram defining a zone where the couple primary loads-secondary loads does not lead to excessive strains. For CABRI, when the number of cycles increases, the couple primary-loads secondary-loads tends towards an asymptotic value that lies within the non failure zone of the Bree diagram. 4. Examination of the methodology proposed to compute the fuel rods thermomechanical behaviour The SCANAIR computer code [3] is devoted to the modelling of the complex physical phenomena occurring during fast power transients. Three modules are closely linked: - The thermal module calculates the radial conduction in the fuel and the clad, as well as clad-to-coolant heat transfer in sodium or water conditions. The coolant flow is computed thanks to a one-dimension single-phase fluid model. - The fission gas behaviour module calculates the swelling of fission gas bubbles, the grain boundary failure within the fuel and the gas flow into free volumes. - The mechanical module calculates the strain contributions to the fuel and clad deformation (thermal expansion, elastic, plastic, strain simulating the fuel expansion induced by the presence of cracks and fuel swelling due to gaseous fission product). The fuel and clad thermo-mechanical models were qualified using separate effects tests and integral tests performed in CABRI-REP-Na programme. A specific validation of the clad-towater heat transfer has been done for conditions representative of the CABRI core fuel rods 3/5 190 of 455
(flow rate, pressure and temperature). This validation is based on the comparison to experimental results of tests performed in NSRR reactor and PATRICIA CEA facility for fast transient transfers. The validation is also demonstrated for late phase film boiling by comparison to WINFRITH test results. In the SCANAIR code, the clad-to-coolant heat transfer is described by a classical heat transfer coefficient approach which is estimated by correlations. The water boiling phenomena (that increase the heat transfer in nucleate boiling and degrade it in transition boiling) and film boiling are modelled. Heat transfer correlations are often semi or completely empirical and are validated in steady state conditions. During fast transient conditions, the radial temperature profile in the coolant can be much steeper than in steady state conditions and the shape of the boiling curve is different (see Figure 1). fuel gap clad fluid Heat - flux Boiling Crisis flow (if any) Intense transient vaporization at the clad surface Transition boiling : degradation of heat t f due to vapor film thermal insulation Transient conduction in liquid Film boiling thermal conduction radiative + solid/solid conductanc e Boiling heat transfer Natural convection Tsat Tsat+20 K Tsat+300K to Tsat+650K Steady - state Clad surface temperature Fig 1: Clad-to-water heat transfer modelling in SCANAIR The maximal temperature reached during fast transient is mainly linked to the boiling crisis occurrence and the film boiling coefficient. Thus a specific critical heat flux correlation has been developed for transient conditions, leading to higher critical heat flux compared to steady condition. A specific film boiling coefficient based on the Sakurai model [4] and derived from the Bromley correlation has also been implemented. In NSRR tests, in the early stage of the film boiling regime (i.e. when the clad temperature reaches its maximum value), the experimental heat fluxes recorded are 3 to 5 times higher than the predicted values [5]. Therefore a correcting coefficient has been applied on the Sakurai correlation. 1200 1000 Outer cladding maximal temperature NSRR tests and PATRICIA_112_041 PATRICIA 112_0141 Calculation (°C) 800 600 400 200 Tmax Best Estimate Tmax conservative 0 0 200 400 600 800 1000 1200 Measurement (°C) Fig2 : Comparison of computed and measured maximal outer cladding temperature reached during NSRR and PATRICIA 112_041 tests 4/5 191 of 455
Page 2 and 3:
© 2009 European Nuclear Society Ru
Page 4 and 5:
RESEARCH REACTOR COALITIONS - SECON
Page 6 and 7:
- Eastern European Research Reactor
Page 8 and 9:
ut a comprehensive alignment of tec
Page 10 and 11:
EERRI will be launched. As noted ab
Page 12 and 13:
Nuclear material in the form of hig
Page 14 and 15:
The GTRI domestic radiological mate
Page 16 and 17:
2. State of the art For fuel plate
Page 18 and 19:
It is known since the early days of
Page 20 and 21:
End of 2008 first DU-8wt.%Mo (deple
Page 22 and 23:
References [1] D. AB. Robinson et a
Page 24 and 25:
• CNEA have been working in the f
Page 26 and 27:
O 75 Bignan.doc - DI - 1 / 10 20/02
Page 28 and 29:
O 75 Bignan.doc - DI - 3 / 10 20/02
Page 30 and 31:
O 75 Bignan.doc - DI - 5 / 10 20/02
Page 32 and 33:
O 75 Bignan.doc - DI - 7 / 10 20/02
Page 34 and 35:
O 75 Bignan.doc - DI - 9 / 10 20/02
Page 36 and 37:
THE EAST EUROPEAN RESEARCH REACTOR
Page 38 and 39:
namely Jozef Stefan Institute TRIGA
Page 40 and 41:
Information and organizational issu
Page 42 and 43:
Action Item Table 3. Description (t
Page 44 and 45:
Table 6. Materials/fuel test experi
Page 46 and 47:
In a recent development, it should
Page 48 and 49:
1. Introduction: a renewed context
Page 50 and 51:
interaction, close retention of fis
Page 52 and 53:
3.3 Reference concept and alternati
Page 54 and 55:
changes can be caused by void swell
Page 56 and 57:
For its manufacturing, an additiona
Page 58 and 59:
minor actinides (MA) considered as
Page 60 and 61:
In France, the decision to build a
Page 62 and 63:
eactors (HFR, OSIRIS and then JHR)
Page 64 and 65:
DECOMMISSIONING PROGRESS OF THE DOU
Page 66 and 67:
Page 68 and 69:
Page 70 and 71:
SECURITY OF SUPPLY FOR FISSION MEDI
Page 72 and 73:
But the worst crisis developed by e
Page 74 and 75:
IRE and COVIDEN are following close
Page 76 and 77:
Fig 1. Design of the core and refle
Page 78 and 79:
Table 3: Set of detailed fuel funct
Page 80 and 81:
For the thermal-mechanical analysis
Page 82 and 83:
Behaviour under conditions represen
Page 84 and 85:
6. References [1] - MC. Anselmet, G
Page 86 and 87:
2. Advanced nuclear fuel cycles The
Page 88 and 89:
3.3 India In addition to the ration
Page 90 and 91:
Session II Fuel Development 90 of 4
Page 92 and 93:
1. Introduction Since 1957, date of
Page 94 and 95:
A 3.1. Place a boron insert in a hi
Page 96 and 97:
Finally, a new tool was defined and
Page 98 and 99:
the end user (CEA), to define the f
Page 100 and 101:
Previous papers discussed character
Page 102 and 103:
(a) (b) (c) (d) (e) (f) (g) (h) (i)
Page 104 and 105:
The results of a third reported irr
Page 106 and 107:
In order to reproduce the heat tran
Page 108 and 109:
25 OXIDE THICKNESS 20 Kim et al pH=
Page 110 and 111:
Heavy ion irradiation of UMo7/Al fu
Page 112 and 113:
For the lowest flux values tested d
Page 114 and 115:
127 I beam 127 I beam 0 5 10 15 20
Page 116 and 117:
Weight fractions (%) U(α) UO 2 γU
Page 118 and 119:
activities to meet the need. The co
Page 120 and 121:
Heat capacity Information Thermal c
Page 122 and 123:
Decision point Activity Phase 2: Fu
Page 124 and 125:
IRIS PROGRAM: IRIS4 FIRST RESULTS F
Page 126 and 127:
The main characteristics of the IRI
Page 128 and 129:
4. In-pool plate thickness measurem
Page 130 and 131:
At that stage of IRIS4 irradiation
Page 132 and 133:
extrapolated thermal property value
Page 134 and 135:
optical microscope, acoustic emissi
Page 136 and 137:
CD WIRES AS BURNABLE POISON FOR THE
Page 138 and 139:
Figure 1. MCNP geometry model of fu
Page 140 and 141: considered carefully: (i) maintain
Page 142 and 143: discussed and validated together, k
Page 144 and 145: The as-fabrication Si contents in t
Page 146 and 147: uniform Si diffusion and consequent
Page 148 and 149: Recently, fuel relocation induced b
Page 150 and 151: characteristics of ILs obtained in
Page 152 and 153: - Type 2 (Si content ≥ 5 wt%) : c
Page 154 and 155: 4. Discussion The main contribution
Page 156 and 157: METHODS OF INCREASING THE URANIUM C
Page 158 and 159: • strength properties of Zr-1% Nb
Page 160 and 161: 4. References 1. Birzhevoy G.A., Ka
Page 162 and 163: Dispersion fuel Monolithic fuel ATR
Page 164 and 165: − because of its Newtonian charac
Page 166 and 167: Session III Back-end 166 of 455
Page 168 and 169: Fig.1. The transfer hall (left in c
Page 170 and 171: The shipment included all the SNF f
Page 172 and 173: FRESH AND SPENT NUCLEAR FUEL REPATR
Page 174 and 175: modifications, spent fuel inspectio
Page 176 and 177: The shipment cleared Romanian Custo
Page 178 and 179: steel are chosen as effective gamma
Page 180 and 181: Fig 3. Long lived nuclides radioact
Page 182 and 183: Session IV Innovative Methods in Re
Page 184 and 185: Lower Gr-reflector Al-clad Upper Gr
Page 186 and 187: All described fuel elements were ca
Page 188 and 189: ANALYSIS OF NEW SAFETY CRITERIA FOR
Page 192 and 193: The comparison between clad tempera
Page 194 and 195: VALIDATION OF PLTEMP/ANL V3.6 CODE
Page 196 and 197: ΔT p 0.0234 2 ⎪⎧ q[W/cm ] ⎪
Page 198 and 199: Table II. Hot Channel Factors for B
Page 200 and 201: for the U-8Mo fuel meat [5]. The po
Page 202 and 203: correlation of Dittus-Boelter; the
Page 204 and 205: ROLE OF RELAP/SCDAPSIM IN RESEARCH
Page 212 and 213: SEVERE REACTIVITY INJECTION ACCIDEN
Page 214 and 215: expansion and steam formation were
Page 216 and 217: 3 Conclusion Since a few years, IRS
Page 218 and 219: analysis procedure (ENAA) except vi
Page 220 and 221: References Briesmeister, J.F., 2000
Page 222 and 223: Fig. 1 A geometric diagram of NIRR-
Page 224 and 225: Fuel plate temperatures during oper
Page 226 and 227: the primary circuit in the central
Page 228 and 229: Fig. 3: Surface temperature over th
Page 230 and 231: [4] “Test Irradiations of Full Si
Page 232 and 233: The core is made of 1488 stainless
Page 234 and 235: 4. Commissioning the facility for t
Page 236 and 237: ESTABLISHMENT OF A SINGLE-CRYSTAL F
Page 238 and 239: were provided to MU and INL for thi
Page 240 and 241:
concrete covered with sheets of 1.2
Page 242 and 243:
USE OF FISSION RADIATION IN LIFE SC
Page 244 and 245:
Fig. 3. Scan of an etch track film
Page 246 and 247:
Summary The unique fission neutron
Page 248 and 249:
2. Methods 2.1 Reactor produced rad
Page 250 and 251:
3.2 Viability studies The results o
Page 252 and 253:
DESIGN OF A FLOWING-NAK EXPERIMENTA
Page 254 and 255:
4. Containment rig and sample-holde
Page 256 and 257:
7. Electrical heater The external h
Page 258 and 259:
Page 1 / 7 EVITA: a semi-open loop
Page 260 and 261:
Page 3 / 7 Fig.1: EVITA fuel Genera
Page 262 and 263:
Page 5 / 7 Challenges When operatin
Page 264 and 265:
Page 7 / 7 References: [1] M.C. Ans
Page 266 and 267:
Nuclear Research Institutes, and so
Page 268 and 269:
According to the latest IAEA inform
Page 270 and 271:
18. May Training of operating perso
Page 272 and 273:
2.1 Irradiation Facilities Brief te
Page 274 and 275:
3.1 Detection limits Although it is
Page 276 and 277:
PARTIAL DISMANTLING OF RESEARCH REA
Page 278 and 279:
• Core - liable to full scale rep
Page 280 and 281:
• Necessary individual dosimetry
Page 282 and 283:
SILICON DOPING AT FRM II H. GERSTEN
Page 284 and 285:
The resulting neutron flux density
Page 286 and 287:
4. References [1] Wagner F.M., Knes
Page 288 and 289:
The choice of fuel base and solutio
Page 290 and 291:
3.3 Increasing power beyond current
Page 292 and 293:
A COATING TO PROTECT SPENT ALUMINIU
Page 294 and 295:
The treatment consisted of simple i
Page 296 and 297:
5. Conclusions 1. Immersion of AA 1
Page 298 and 299:
KEEPING AGING RESEARCH REACTORS IN
Page 300 and 301:
inspected in presence of an expert
Page 302 and 303:
After the inspection was finished,
Page 304 and 305:
1 A STRATEGY FOR MANAGING AGEING CO
Page 306 and 307:
3 2. With the aluminium-clad HEU fu
Page 308 and 309:
5 The pool and the support structur
Page 310 and 311:
Fig.2. Reflector element of JRR-4.
Page 312 and 313:
Dimensional change (%) 0.6 0.5 0.4
Page 314 and 315:
SAFETY CONSIDERATIONS FOR CORE MANA
Page 316 and 317:
3 3. Core operation and monitoring
Page 318 and 319:
5 temperature, etc.). Effective sec
Page 320 and 321:
1436 keV, Cs 138 1369 keV, Na 24 2.
Page 322 and 323:
compared with that of the delayed n
Page 324 and 325:
AD-HOC AND PREVENTATIVE MAINTENANCE
Page 326 and 327:
Page 3 of 7 3. SAFARI-1OPERATIONAL
Page 328 and 329:
Page 5 of 7 programs for instrument
Page 330 and 331:
Page 7 of 7 DATE DESCRIPTION DATE D
Page 332 and 333:
MICROSTRUCTURAL ANALYSIS OF MTR FUE
Page 334 and 335:
In sample S3, similar zones could b
Page 336 and 337:
increased temperature, the solid st
Page 338 and 339:
Figure 8 BEI images covering Sample
Page 340 and 341:
660 °C, but since in the former me
Page 342 and 343:
support. Both Governments have eval
Page 344 and 345:
• Removal of sludge from the SNF
Page 346 and 347:
UPGRADED REACTOR SYSTEMS FOR ENHANC
Page 348 and 349:
Parameter HEU LEU a 6.0x10 -5 (°K)
Page 350 and 351:
From 1992 until 2005 the TRIGA-SSR
Page 352 and 353:
Figure9 - Dependency between reacto
Page 354 and 355:
URANIUM CONTAMINATION IN PRIMARY CI
Page 356 and 357:
1.00E+06 1.00E+05 Volume activity (
Page 358 and 359:
6. Acknowledgement This work was pe
Page 360 and 361:
2. Steady State Thermal Hydraulic A
Page 362 and 363:
in the scram, and the respective re
Page 364 and 365:
CORROSION BEHAVIOR OF ALUMINIUM ALL
Page 366 and 367:
3.2. Pitting corrosion of 1050 and
Page 368 and 369:
4. Discussions This study shown tha
Page 370 and 371:
The Steady State core was fully con
Page 372 and 373:
0.E+00 2.E+06 1.40E+07 2.E+06 1.20E
Page 374 and 375:
SYNTHESIS AND CHARACTERIZATION OF G
Page 376 and 377:
0 2 4 6 8 10 120 1,2 100 1,0 80 70
Page 378 and 379:
Element, Wt %, At %, K‐Ratio, Z,
Page 380 and 381:
U/cc, but the target uranium densit
Page 382 and 383:
Fig. 5 Macroscopic cutting view (x
Page 384 and 385:
SELF-ASSESSMENT OF APPLICATION OF T
Page 386 and 387:
2. The Code of Conduct on the Safet
Page 388 and 389:
For emergency preparedness, conside
Page 390 and 391:
inside of a compaction die by blowi
Page 392 and 393:
Fig. 4. A compacted and sintered lu
Page 394 and 395:
THE MANAGEMENT SYSTEM EVOLUTION OF
Page 396 and 397:
etween CRPq specific process and IP
Page 398 and 399:
aspect audits, mainly in relation t
Page 400 and 401:
1 2 3 4 5 6 7 8 9 A B C D E F G H F
Page 402 and 403:
MCNP5 is capable of calculating ter
Page 404 and 405:
Similar to the case of stainless st
Page 406 and 407:
LEU FUEL DISPOSITION AT WWR-M REACT
Page 408 and 409:
Tested fuel assembles are load in t
Page 410 and 411:
The PNPI experience of tests with W
Page 412 and 413:
CURRENT UTILIZATION AND LONG TERM S
Page 414 and 415:
Uusimaa hospital district decided t
Page 416 and 417:
FiR 1 has an important regional rol
Page 418 and 419:
STUDYING OF INFLUENCE OF A NEUTRON
Page 420 and 421:
Definition of crystal structure and
Page 422 and 423:
Microhardness measurement shows, th
Page 424 and 425:
THE SPENT FUEL STORAGE AT THE DALAT
Page 426 and 427:
2. Interim storage of spent fuel On
Page 428 and 429:
A rotating bridge crane of 3.6-ton
Page 430 and 431:
In order to investigate the perform
Page 432 and 433:
(a) (b) Fig. 2. (a) low and (b) hig
Page 434 and 435:
(a) (b) (c) (d) (e) (f) Fig. 5. TEM
Page 436 and 437:
Spot Al Si Mo U Zr G 90.6 7.8 0.6 0
Page 438 and 439:
volume in the material, which affec
Page 440 and 441:
THE STEREOMETRIC ANALYSIS OF GAS PO
Page 442 and 443:
of the crack of pillowing). It show
Page 444 and 445:
One gets the impression that during
Page 446 and 447:
switch from a fast to a thermal spe
Page 448 and 449:
He production to fission ratio vs t
Page 450 and 451:
INSPECTION EXPERIENCE WITH IEA-R1 S
Page 452 and 453:
camera system, received from IAEA i
Page 454:
core in the beginning 2007 (IEA-174
show all

RRFM 2009 Transactions - European Nuclear Society

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?