recent progress in hccb design analysis ying, alice with contributions from m. narula, r. hunt, s....
TRANSCRIPT
Recent Progress in HCCB Design Analysis
Ying, Alice
With contributions fromM. Narula, R. Hunt, S. Park, M. Youssef, W.
Zhang
TBM Meeting February 14-15, 2007
UCLA
Summary
• Efforts were carried out in the following areas:– Continued thermo-fluid design analysis for
Helium coolant manifold designs (Narula)– Progress in the integrated design analysis
approach– Input to FMEA – Nuclear optimization of the HCBB TBM with
varying Li-6 enrichment and plan for 3-D analysis (Youssef- 10 minutes)
Basic Configuration and Partnership Scheme for HCCB remain the same as Aug. 2006
HCCB Joint PartnershipHCCB Joint Partnership
The proposed US HCCB sub-module will occupy 1/3 of an ITER horizontal half-port
US HCCB TBM sub-module (710 389 510 mm)
RAFS FW with He coolant channels
He purge gas pipe
Be pebbles
Ceramic breeder pebbles
Cooling plate
Engineering Design Analysis Emphasizes Integrated Engineering Design Analysis Emphasizes Integrated Computer Aided Engineering (CAE) ApproachComputer Aided Engineering (CAE) Approach
• Preliminary effort focuses on Thermo-fluid and Structural Thermo-mechanical coupling
• EM and pebble bed thermomechanics integration as the next step
SCTPre
SCTsolver
SCTpost
FLDUTIL
SC/Tetra
ANSYS
.MDL file format input to SC/Tetra preprocessor
.cdb file format to input geometry and temperature load for ANSYS
Thermo-fluid Analysis
Velocity, Temperature, and Pressure in fluid domain
Temperature in solid domain
Primary and Thermal Stress Analysis
Stress and Strain in the solid domain
Transient and steady state thermal stress Analysis
CAD model CADthru
Fix CAD model
.MDL model
Example
Code choices for EM: ANSYS/OPERACode choices for pebble bed thermomechanics: ANSYS/MARC
Elements in SC/T mesh : 3 million (first order tetrahederons and prisms)
Elements in ANSYS mesh: 0.25 million (second order tetrahederons, etc.)
In ANSYS only the solid domain is meshed with second order elements (SOLID 186). The mid-node temperature loads are interpolated during data transfer
Data Transfer Between Various Physics Simulation Codes
Nodal/Element Based Data Interpolation
SOLID186 - 3-D 20-Node Structural Solid
first order tetrahederons
High order element (accuracy) can not be applied in a full simulation model
16-channels model
first order tetrahederons remain with reduced number of elements
ANSYS Structural
mesh
CFD SC/Tetra mesh
3-channels model
Higher order elements used with mid-node temperature interpreted
Stress and deformation calculations were performed to guide manifold design
Deformation + un-deformed edges and temperature distribution
first order tetrahedral elements used in the structure to restrict the number of computational nodes below 0.5 million
Temperature (Body force load) and pressure surface loads as well as nodal information imported from SC/Tetra CFD code to ANSYS structural code
BC: Two edges at the back clamped
• Outlet coolant duct deformed significantly
• shape and wall thickness need to be redesigned
Von Mises stress and displacement
He Pressure applied to the coolant channels
Plots of Von Mises stress & displacement
Plot of stress & displacement at mid-plane of side wall coolant channelsFW Outlet 1/2
FW helium distributor 1/4
Plots of Von Mises Stress and Displacement on First and Side Walls
FWSide Wall
Zorigin
0.55
0.51
0.010.14
0.49
0.29 0.04 0.030.44
0.498
Slice show of Von Mises Stress distribution at different Z cutting planes (High stress magnitudes located at
manifold plane)Maximum stress at FW Ferritic steel structural surface: 230 MPaYield strength (Y)at 550oC ~ 340 MPa
p < 1.5 Sm and p + t < 3 Sm (Sm = 1/3 Y)
Breeding units (4)
FW cooling manifold assembly
Breeding zone cooling plate manifold assembly
Cap (2)
FW
structural
panel
Exploded view of the HCCB sub-module A completely assembled
breeding unit to be inserted into the structural box
The HCCB is based on Edge-on configurationThe HCCB is based on Edge-on configuration
• Hot isostatic pressing (HIP) technology to join square tubes to form the FW structural panel, and fabrication of other elements such as internal cooling plates.
• Electron-beam, laser welding, and possibly other techniques to join manifolds to the first-wall structural panel and internal cooling plates.
Be pebbles filled into places
through Upper Cap
Manufacturing Process for breeder unit cooling plate is under evaluation (similar cooling plate being used in HCPB, HCLL,
etc. concepts)
2 Mirrored Sections made through investment casting
SC2-S
Holes in top cover used for filling with breeder pebbles
Breeder cover plates welded onto coolant channel parts
SC2-C
SC2-U
Casted Channel section HIPed to bent plates
Poloidal height = 590 mm
Radial depth= 362 mm
Plate thickness = 6mm
Breeding zone width = 11 to 18 mm
Weld caps length= 4 x(11+18+362x2) = 3012 mm
Side weld length = 2x 2x(18+ 590)=2432 mm Weld length per BU= 5444mm
Hip length per BU= 185256 mm
64 channels Hip length= 64 x2 x (362+362+23)= 92628 mm
Input to FMEA: Example
Index
Component TBM-BZ-distributor plate welds
OP. ST. No
Failure Mode Loss of leak tightness
Causes Defects in manufacturing;Abnormal operating conditions (e.g.: vibrations and/or thermal-mechanical stress not foreseen by design);Fatigue
Preventative Actions on Causes
Test and inspection during manufacturing & assembly
Consequences • Generation of bypass line between two BZ cooling paths;
• Generation of flow unbalance among the coolant channels and leading to inadequate cooling for one or more BUs;
• Increase of local temperatures due to inadequate cooling;
• Cause of coolant leak into TBM Box due to loss of leak tightness of BU Back-Cap Weld or Be Enclosure Plate-Weld;
• Consequences as for the "TBM-BU-Back-Cap-Weld - Loss-of Leak Tightness" or "TBM-Be Enclosure Plate-Weld-Loss-of Leak Tightness" could follow
Frequency 44108.3 mm x 5 x10-8 /h.m = 2.2 e-6/h Section A cover weld to front of Section A distributor plates
Breeding zone manifold formed by 4 radially dividing “plates” and 2 ducts with grooves
Example List of Failure Modes with Components
Component Failure Mode Component Failure Mode
TBM-FSW Rupture TBM-FSW-CapWeld-Front Loss of leak tightness- He purge
Plate Deformation TBM-FSW-CapWeld-Rear Loss of leak tightness- He Coolant
Break in internal hipping joint
TBM-Upper Cap Be filling tubes
Loss of leak tightness
TBM-FSW-CoolCh Partial or complete plugging TBM-BU Insert/Be Enclosure plate
Plate deformation
TBM-FSW-Be Detachment of Be layer from FSW
TBM-BU-Upper/Lower-Caps-Weld
Loss of leak tightness
TBM-Cap Rupture TBM-BZ-front distributor closure plate-Weld
Rupture/Loss of leak tightness
Plate Deformation TBM FW Manifold cover plate
Rupture/Loss of leak tightness
Break in internal hipping joint
TBM-FW coolant supply and return channel blocks
Rupture/Loss of leak tightness
TBM-Cap-CoolCh Partial or complete plugging TBM-BZ helium coolant supply ducts-Weld
Loss of leak tightness
Figure 15 View of majority of manifold systems upon assembly
FW manifold total weld length (Figs: 11-14)= 14177.2 mm
Breeding unit manifold total weld Length (Figs: 5-10)= 44108.3 mm
BU caps + side walls (Fig. 4) = 4 x5444= 21776mm
BU/FSW (Fig. 3) = 3980 mm
Cap/FSW (Fig. 2) = 6600 mm
Hip length
FW (Fig. 1) = 270528 mm
BU (Fig. 4) = 4 x 185256 mm = 741024 mm
Total weld length = 90641.5 mm
Total hip length = 1011552 mm
Longitudinal failure rate = 5 x10-8 /h.m (high end)
Failure rate for welds = 4.5 x10-6/h
Hipping failure rate use failure rate for straight pipe= 1 x10-9 /h.m
Failure rate from hipping = 1x10-6/h
Draft Qualification program for HCCBDraft Qualification program for HCCB
Qualification Program Activity Assumed Milestone
Development of HCCB TSD (Technical Specification Document)
1st Draft during preliminary design review Dec. 2008
2nd Draft during bid package document complete Sep. 2009
Final during HCCB final design review Dec. 2012
Development of Structural Design Criteria
Draft during preliminary design review Dec. 2008
Final during fabrication contract award Mar. 2010
Tests and In-Service Inspections (Projected tasks and dates)
Small-scale FW helium flow design verification tests Dec. 2007
HCCB 1/3 scale helium flow and FW heat flux testing Oct. 2010
Prototype fabrication starts (full scale) Apr. 2011
Prototype qualification tests start Mar. 2012
Safety and Regulatory Support
Input to RPrS due Mar. 2007
Input to RFS due Jun. 2013
HCCB ITER Sub-module
HCCB sub-module final design review Dec. 2012
HCCB Sub-module fabrication starts Dec. 2012
HCCB sub-module acceptance tests start Sep. 2013
HCCB Sub-module delivered to Host Party Jul. 2014
Near-term tasks1. Perform structural analysis (primary + thermal stress) to validate breeding zone manifold design
2. Develop flow distribution schemes for three sub-modules
FW manifold
Breeding zone manifold
Flexible support (4)
Key-way (3)
US sub-module
He coolant pipes (3): Inlet, outlet, by-pass
Common Back Wall Manifold Assembly