U PDATED ARIES-ACT P OWER C ORE D EFINITION AND S I C B LANKET X.R. Wang, M. S. Tillack, S. Malang F. Najmabadi and L.A. El-Guebaly ARIES-Pathways Project.

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Presentation transcript:

U PDATED ARIES-ACT P OWER C ORE D EFINITION AND S I C B LANKET X.R. Wang, M. S. Tillack, S. Malang F. Najmabadi and L.A. El-Guebaly ARIES-Pathways Project Meeting Gaithersburg, MD May 30-June 1, 2012

O UTLINE  Updates on the overall layout and integration of the ARIES-ACT power core configuration Definition of the power core components based on new radial builds  blankets, divertors, structural ring, VV and LT shield Locations of the control coils and saddle coil Layout of the LiPb and He access pipes connecting to the sector and ring headers Size and location of the vacuum pumping ducts  Updates on the SCLL blanket design and optimization Internal details, such as the parameters, dimensions of the IB and the OB blankets Primary and thermal stresses of the last iteration  Summary 2

D EFINITIONS OF THE ARIES-ACT P OWER C ORE C OMPONENTS 3  Inboard blanket straight from bottom to top and LiPb running behind and above the upper divertor manifold feeding the LiPb to the IB blanket from bottom behind the divertor structure  Outboard blanket-I and II 4 cm stabilizing shells attached to the OB-II at the top & bottom, and 1 cm kink shell in the middl e LiPb manifolds at the bottom  Top and bottom divertor target and structure shorter inboard divertor slots (comparing to ARIES-AT) Helium cooled two zone W divertor design concept Finger for q>7 MW/m 2, flat-type plate for q<7 MW/m 2  Structural ring a closed ring in poloidal direction will provide enough mechanical strength to support the blankets and divertors all the inboard/outboard blankets upper and lower divertor are attached to the structural ring by bolts or mechanical keys to form a closed unit (replacement unit) the replacement unit is supported at bottom through the VV and LW shield the entire unit is free expansion in all directions Replacement unit (1/16) Question to ARIES edge plasma experts: Do the short inboard divertor slots work for your requirement? Question to ARIES edge plasma experts: Do the short inboard divertor slots work for your requirement?

T WO -Z ONE D IVERTOR C ONCEPT C AN B E A PPLIED IN THE ARIES-ACT 4 Plate Finger q’’< 7 MW/m 2 q’’> 7 MW/m 2 (up to 13 MW/m 2 ) ARIES He-cooled W divertor design concepts: 1.Finger, diameter=~20 mm, q allow =~13 MW/m 2, ~ 0.55 million fingers for a power plant 2.T-Tube, diameter=~15 mm, tube length= ~10 cm, q allow =~11 MW/m 2 3.Plate, 20 cm(tor.) x 100 cm (pol.), q allow =~9 MW/m 2, ~750 plate units for a power plant 4.Finger-plate two zone concept Cartridge with both slots and jets being combined Limit fingers to the zones with the highest heat flux High heat flux region Low heat flux region pol. tor. rad.

B ACKUP D ESIGN O PTION OF THE ARIES- ACT P OWER C ORE 5 Inboard blanket straight from bottom to top divertor region, but no LiPb running behind and above the upper diveror being tapered from 35 cm to 20 cm at the bottom divertor region  Top and bottom divertor regions slightly longer inboard divertor slots (comparing to the reference design) an additional helium-cool steel shielding required at the upper divertor region (between structural ring and divertor structure)  Structural ring being tapered from 20 cm to 15 cm at the inboard divertor region 1/16 Replacement unit (backup design option)

O VERALL L AYOUT AND I NTEGRATION OF THE ARIES-ACT P OWER C ORE 6  The VV will be a webbed-structure cooled by He and will be run hot (~ ͦ C) to minimize tritium migration to the VV. In the CAD drawings: ~5 cm at inboard ~10 cm at top, bottom and outboard ~10 cm for the port walls  Low temperature shield is cooled by water and run at room temperature.  The size and locations of pumping ducts will be the same as the ARIES-AT.  Control coils are supported by the structural ring and be capable of removing to upper during the maintenance.  There is only ~5 cm space for local shield between outboard TF legs and port side walls, therefore, an inner door on the VV will be required for protecting the coils, and the door can be cooled by helium.  The saddle coil would be attached to the front of the inner door and removed together with the door during maintenance.  Cutting/Re-welding or Re-brazing the coolant lines are located inside of the VV. Cutting/Re-welding or re- brazing line of access pipes Cross section of the ACT power core

B ACKUP O PTION OF THE L OCAL W ATER - COOLED S HIELD 7  There is only one door at the end of the maintenance port.  The saddle coils are attached to the back of the structural ring and needs to be removed through the port before removing the control coils during the maintenance.  The TF coils have to be enlarged in order to increase the space between the outboard TF legs and the port side walls. ~5 cm space for local shield

C ONFIGURATION OF THE V ACUUM V ESSEL AND P ORTS 8 1 sector12 sectors  The VV will be designed as the webbed-structure cooled by the helium, including the VV, port and the outer door (Farrokh’s talk).  The geometry definition is based on maintenance requirements, integration of the overall power core and primary stress iterations. Penetrations of access pipes

A RRANGEMENT OF THE C OOLANT A CCESS P IPES C ONNECTING TO R ING H EADERS 9 Reference design Other options discussed before  There are 7 concentric assess pipes with cold coolant in the annular and hot in the center 3 LiPb access pipes for the blankets 2 He access pipes for the upper and lower divertors 2 He access pipes for the structural ring ARIES-AT like

ARIES-ACT CAD D RAWINGS A RE A VAILABLE 10

Schematic of the Pressure and Pressure Drops for the ARIES-ACT Blanket  The results indicate that the pressure and pressure drops of the ARIES-AT blanket were underestimated (~1 MPa at the inlet and 0.75 MPa at the exit).  The configurations, parameters and dimensions of the IB&OB blankets need to be designed to accommodate the pressure of ~2 MPa and meet the stress limits ( ~190 MPa for the combined primary and thermal stresses )  Design iterations and optimizations have been performed based on primary stress limits and the volume fraction of the SiC. 11 ARIES-ACT SiC blankets “ Power core performance parameter (SCLL)” presented by Tillack at ARIES Group Meeting, 6 February 2012.

Total number of the modules per sector=8 (6 inner modules and 2 outer modules) The fluid thickness in the FW, SW and BW annular=10 mm (4 mm for the ARIES-AT) The number of the sub-ducts=18 (21 for the ARIES-AT) Wall thickness of the outer and inner ducts= 5 mm Thickness of the front and back ribs=4 mm (2 mm for the ARIES-AT) Thickness of the ribs at the two sides with pressure balance= 2 mm Diameter of the curvature for the FW and BW, 35 cm Configuration Definition, Dimensions and Composition of the IB Blanket Inner module Outer module Increase the number of the ribs from 4 to 10 Increase the rib thickness from 2 mm to 4 mm at the outer side Increase the thickness of the outer SW from 5 to 20 mm FW, 2.0 cm 54.5% SiC 45.5% LiPb BW, 2.0 cm 54.5% SiC 45.5% LiPb Inner SW, 2.0 cm 54.5% SiC 45.5% LiPb Inner SW, 2.0 cm 54.5% SiC 45.5% LiPb BW, 2.0 cm 55.6% SiC 44.4% LiPb FW, 2.0 cm 55.5% SiC 44.5% LiPb Outer SW, 3.5 cm 81.3% SiC 18.7% LiPb FW Inner module Inner and Outer Modules (6 inner and 2 outer modules per sector) Outer module 35 cm 12 Composition of the outer module:

Configuration Definition, Dimensions and Composition of the OB Blanket-I Total number of the module for each OB blanket sector=12 (10 inner modules and 2 outer modules) Total number of the sub-ducts=18 (23 for the Old OB-I, 4 in the front, 13 at the back and 6 at the sides) The wall thickness of the outer/inner ducts=5 mm The fluid thickness in the annular= 10 mm (4 mm for the Old OB-I) Rib thickness in the front and back=4 mm (2mm for the Old OB-I) Rib thickness on both sides=2 mm Diameter of the curvature for the FW and BW=30 cm Inner module Outer module Increase the thickness of the outer SW from 5 to ~15 mm Increase the numbers of the rib from 2 to 5 Increase the thickness of the outer SW ribs from 2 to 4 mm FW, 2.0 cm 55.7% SiC 44.3% LiPb Inner SW, 2.0 cm 51.0% SiC 49.0% LiPb BW, 2.0 cm 53.8% SiC 46.2% LiPb FW, 2.0 cm 55.3% SiC 44.7% LiPb Inner SW, 2.0 cm 51.0% SiC 49.0% LiPb Outer SW, 3.0 cm 75.6% SiC 24.4% LiPb BW, 2.0 cm 55.3% SiC 44.7% LiPb Inner and Outer Modules (10 inner and 2 outer modules per sector) First Wall Inner module Outer module 30 cm 13 Composition of the outer module:

Configuration Definition, Dimensions and Composition of the OB Blanket-II Total number of the module for each blanket sector=12 (10 inner modules and 2 outer modules) Total number of the sub-ducts=24 (20 for the Old OB-II) The wall thickness of the outer/inner ducts=7 mm Rib thickness at 4 corners=6 mm (4 mm for the Old OB-II) Rib thickness on both sides=2 mm The fluid thickness at the annular=10 mm (8 mm for the Old OB-II) Diameter of the curvature for the FW and back wall=45 cm Inner module Outer module Increase the thickness of the outer SW from 5 to 22 mm Increase the thickness of the rib at the outer SW from 2 to 6 mm Increase the numbers of the rib at the outer SW from 5 to 9 FW, 2.4 cm 63.8% SiC 36.2% LiPb Inner FW, 2.4 cm 60.3% SiC 39.7% LiPb Outer BW, 3.9 cm 83.9% SiC 16.1% LiPb BW, 2.4 cm 63.6% SiC 36.4% LiPb FW, 2.4 cm 63.3% SiC 36.7% LiPb Inner SW, 2.4 cm 60.3% SiC 39.7% LiPb BW, 2.4 cm 63.0% SiC 37.0% LiPb Inner and Outer Modules (10 inner and 2 outer modules per sector) 45 cm 14 Composition of the outer module: Inner module 30 cm

Design limits: ~100 MPa for the primary stress (splitting from the total allowable stresses of 190 MPa) Primary Stress of the IB Blanket  Maximum local stress is located at the 4 corners of ribs.  The stress in most regions of the FW, BW and SWs is less than ~50 MPa. First wall 15 First wall Stress distribution of the outer module (Deformed shape scaled by 50 times)  The local primary stress occurs at the corners of the inner duct (~103 MPa) for a 2 cm thick side wall, and the stress at the most region is < 60 MPa.

Maximum local stress is located at the corners of ribs and it is ~71 MPa. The stress in most regions of the FW, BW and SWs is less than ~55 MPa. ( Deformed displacement is scaled by 30) Total deformation=0.7 mm Primary Stress Results of the OB Blanket-I First wall First wal l Primary stress of the OB-I 16

 Maximum local stress is located at the 4 corners of the inner duct, it is ~80 MPa.  The stress in most regions of the FW, BW and SWs is less than ~53 MPa.  Maximum total deformation is ~0.8 mm. Pressure stress distribution of the OB-II Primary Stress of the OB Blanket-II First wall Back wall First wall 17

Temperature Profiles of the IB for Thermal Stress*  Max. temperature of the SiC is ~960 ͦ C(allowable SiC temperature <1000 ͦ C ) and max. LiPb temperature is ~1100 ͦ C.  Front-to-back module temperature differences are modest, ~100 ͦ C at the bottom and ~130 ͦ C at the top.  Thermal stresses at both bottom and top sections will be calculated. * “ Power core performance parameter (SCLL)” presented by Tillack at ARIES Group Meeting, 6 February

Thermal Stress Analysis in the Bottom Section of the Inboard Blanket B.Cs: 1.Free expansion, and allowing for free bending 2.Free expansion, bending suppressed at the bottom plane Pressure load: 1.95 MPa at annular ducts and 1.65 MPa at the center duct Thermal stress distribution Max. thermal stress =~91 MPa Pressure stress<~50 MPa Total stresses=~141 MPa Thermal stress <60 MPa Max. pressure stress=~88 MPa Total stresses=~148 MPa 19  Max. combined primary and thermal stresses are ~141 MPa for the B.C 1, and ~178 MPa for the B.C. 2 (allowable stress=190 MPa)

Thermal Stress Analysis in the Top Section of the Inboard Blanket B.Cs: 1.Free expansion, and allowing for free bending 2.Free expansion, bending suppressed Pressure load: 0.95 MPa at the annualr ducts and 0.85 MPa at the center duct Thermal stress distribution  Max. combined primary and thermal stresses are ~142 MPa for the B.C 1, and ~182 MPa for the B.C. 2 (allowable stress=190 MPa) 20 Max. thermal stress =~118 MPa Pressure stress<~24 MPa Total stresses=~142 MPa Max. pressure stress=~42 MPa Thermal stress <52 MPa Total stresses=~94 MPa Max. thermal stress =~118 MPa Pressure stress<~24 MPa Total stresses=~142 MPa Max. pressure stress=~42 MPa Thermal stress <52 MPa Total stresses=~94 MPa

SUMMARY  The overall power configuration and integration of the ARIES-ACT power core have been updated to new radial builds. The working CAD drawings are now available at ARIES web site:  The parameters of the SiC/LiPb blankets, including the size of the module, the numbers of the modules per sector, FW curvatures, wall thickness, rib thickness and rib spacing have been re-defined and optimized based on the primary stresses and the SiC volume fraction.  Thermal stress analysis of the inboard blanket has been performed and the results indicate that the stress limits are satisfied.