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LISTA DELLE TABELLE
Tabella 1.1 Member Organizations of the IRIS Consortium ... 7
Tabella 1.2 IRIS Schedule Objectives ... 7
Tabella 1.3 Implications of Safety-by-Design Approach ... 9
Tabella 1.4 IRIS Response to PWR Class IV Events ... 9
Tabella 1.5 Major IRIS Design Parameters ... 10
Tabella 1.6 IRIS Reactor Vessel Parameters ... 11
Tabella 1.7 IRIS’s accomodation of Core upgrades ... 17
Tabella 1.8 Refueling options for current IRIS core design ... 17
Tabella 1.9 IRIS Steam Generator Parameters (One of Eight) ... 21
Tabella 2.1 Steam Generator Degradation Definition ... 36
Tabella 2.3 Worldwide causes of steam generator tube repair ... 38
Tabella 2.4 Steam Generator Chemical Cleaning in the United States... 44
Tabella 2.5 Location of Defects Requiring Tube Plugging at Units Throughout the World (Percent of Tube Plugged) ...45
Tabella 2.6 Steam Generators Replacements in the United States ... 48
Tabella 2.7 Planned Steam Generator Replacements in the United States (1995-1999) ... 50
Tabella 2.8 Worldwide cost for unplanned steam generator outages ... 51
Tabella 2.9 Reactor with greater than 2% Tubes Plugged (1995, United States) ... 52
Tabella 2.10 Planned steam generator replacements ... 53
Tabella 2.11 Babcok&Wilcox PWR Replacement Stean Generator Experience ... 54
Tabella 2.12 Selection of NDT techniques for tube tesing ... 57
Tabella 2.13 Flaw Detection Performance by tube material and NDT technique ... 58
Tabella 3.1 Stress fields ahead of a crack tip for Mode I and Mode II... 67
Tabella 3.2 Non-zero stress and displacement components in Mode III ... 68
Tabella 3.3 Crack tip displacement fields for Mode I and Mode II... 68
Tabella 4.1 Main Design Differences between IRIS and a Conventional (U-Bend Type) SG. 97 Tabella 4.2 Effects of reduced steam pressare and increased superheating... 98
Tabella 4.3 Sensitivity effects of steam pressare, steam and feedwater temperature ... 99
Tabella 4.4 Actual IRIS Steam Generator sizing... 100
Tabella 4.5 Yield Onset and Fully Plastic Pressures for Sy,d = 213 MPa... 107
Tabella 4.6 Tube length in tension (With Axial load) t = 2.11 ... 118
Tabella 4.7 Tube length in tension (Without Axial load) t = 2.11 ... 118
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Tabella 4.9 Tube length in tension (With Axial load) t = 1.54 ... 118
Tabella 4.10 Contribution of ovality and thickness reduction on stresses ... 119
Tabella 4.11 Crack parameters for ASME III... 121
Tabella 4.12 Circumferential crack in Tube round, t = 2.11 mm... 127
Tabella 4.13 Circumferential crack in Tube round, t = 1.918 mm... 127
Tabella 4.14 Ovality contribution on crack propagation ... 134
Tabella 4.15 Tube-to-Header connection contribution on J-Integral values... 136
Tabella 4.16 Threshold Stress Intensità values for Alloy 690 and 800 ... 138
Tabella 5.1 Geometrical parameters for IRIS SG RELAP Model ... 143
Tabella 5.2 Summary of Heat structures in SG nodalization... 143
Tabella 5.3 Time sequence of events for Loss of Load/Turbine Trip... 147
Tabella 5.4 Time sequence of events for Feed Line Break... 152
Tabella 5.5 Time sequence of events for Locked Rotor ... 158
Tabella 6.1 Damping factor for SSE (Regulatory Guide 1.61)... 164
Tabella 6.2 Dynamic Equivalence of SG FEM models ... 172
