UPDATED ARIES-ACT POWER CORE DEFINITION AND SIC BLANKET 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 OUTLINE 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 DEFINITIONS OF THE ARIES-ACT POWER CORE COMPONENTS 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 middle 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/m2, flat-type plate for q<7 MW/m2 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) 3 Question to ARIES edge plasma experts: Do the short inboard divertor slots work for your requirement? TWO-ZONE DIVERTOR CONCEPT CAN BE APPLIED IN THE ARIES-ACT Plate Low heat flux region q’’< 7 MW/m2 Finger High heat flux region q’’> 7 MW/m2 (up to 13 MW/m2) rad. tor. pol. ARIES He-cooled W divertor design concepts: 1. Finger, diameter=~20 mm, qallow=~13 MW/m2, ~0.55 million fingers for a power plant 2. T-Tube, diameter=~15 mm, tube length= ~10 cm, qallow=~11 MW/m2 3. Plate, 20 cm(tor.) x 100 cm (pol.), qallow=~9 MW/m2, ~750 plate units for a power plant 4 4. Finger-plate two zone concept Cartridge with both slots and jets being combined Limit fingers to the zones with the highest heat flux BACKUP DESIGN OPTION OF THE ARIESACT POWER CORE 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) 5 OVERALL LAYOUT AND INTEGRATION OF THE ARIES-ACT POWER CORE The VV will be a webbed-structure cooled by He and will be run hot (~300-500 ͦ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. Cross section of the ACT power core Cutting/Re-welding or rebrazing line of access pipes The saddle coil would be attached to the front of the inner door and removed together with 6 the door during maintenance. Cutting/Re-welding or Re-brazing the coolant lines are located inside of the VV. BACKUP OPTION OF THE LOCAL WATERCOOLED SHIELD 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 7 CONFIGURATION OF THE VACUUM VESSEL AND PORTS Penetrations of access pipes 1 sector 12 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. 8 ARRANGEMENT OF THE COOLANT ACCESS PIPES CONNECTING TO RING HEADERS Other options discussed before ARIES-AT like Reference design 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 9 ARIES-ACT CAD DRAWINGS ARE AVAILABLE 10 http://aries.ucsd.edu/LIB/CAD/FIGURE/ARIES-ACT/ Schematic of the Pressure and Pressure Drops for the ARIES-ACT Blanket “Power core performance parameter (SCLL)” presented by Tillack at ARIES Group Meeting, 6 February 2012. ARIES-ACT SiC blankets 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 11 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. Configuration Definition, Dimensions and Composition of the IB Blanket Inner module 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 FW, 2.0 cm 54.5% SiC 45.5% LiPb BW, 2.0 cm 54.5% SiC 45.5% LiPb Inner module 35 cm FW Outer module Inner SW, 2.0 cm 54.5% SiC 45.5% LiPb 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 Inner and Outer Modules (6 inner and 2 outer modules per sector) Composition of the outer module: FW, 2.0 cm 55.5% SiC 44.5% LiPb BW, 2.0 cm 55.6% SiC 44.4% LiPb Inner SW, 2.0 cm 54.5% SiC 45.5% LiPb 12 Outer SW, 3.5 cm 81.3% SiC 18.7% LiPb Configuration Definition, Dimensions and Composition of the OB Blanket-I Inner module Inner module 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 FW, 2.0 cm 55.7% SiC 44.3% LiPb BW, 2.0 cm 53.8% SiC 46.2% LiPb Inner SW, 2.0 cm 51.0% SiC 49.0% LiPb Outer module 30 cm Outer module First Wall 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 Inner and Outer Modules Composition of the outer module: FW, 2.0 cm 55.3% SiC 44.7% LiPb BW, 2.0 cm 55.3% SiC 44.7% LiPb Inner SW, 2.0 cm 51.0% SiC 49.0% LiPb (10 inner and 2 outer modules per sector) Outer SW, 3.0 cm 75.6% SiC 24.4% LiPb 13 Configuration Definition, Dimensions and Composition of the OB Blanket-II Inner module Inner module 45 cm 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 FW, 2.4 cm 63.3% SiC 36.7% LiPb BW, 2.4 cm 63.0% SiC 37.0% LiPb 30 cm Inner SW, 2.4 cm 60.3% SiC 39.7% LiPb 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 Inner and Outer Modules (10 inner and 2 outer modules per sector) Composition of the outer module: FW, 2.4 cm 63.8% SiC 36.2% LiPb BW, 2.4 cm 63.6% SiC 36.4% LiPb Inner FW, 2.4 cm 60.3% SiC 39.7% LiPb 14 Outer BW, 3.9 cm 83.9% SiC 16.1% LiPb Primary Stress of the IB Blanket First wall First wall Stress distribution of the outer module (Deformed shape scaled by 50 times) Design limits: ~100 MPa for the primary stress The local primary stress occurs at the corners of the inner duct (~103 MPa) for a 2 cm thick side (splitting from the total allowable stresses of 190 wall, and the stress at the most region is < 60 MPa) MPa. Maximum local stress is located at the 4 corners 15 of ribs. The stress in most regions of the FW, BW and SWs is less than ~50 MPa. Primary Stress Results of the OB Blanket-I First wall Primary stress of the OB-I First wall (Deformed displacement is scaled by 30) Total deformation=0.7 mm 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. 16 Primary Stress of the OB Blanket-II Back wall First wall First wall Pressure stress distribution of the OB-II 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. 17 Temperature Profiles of the IB for Thermal Stress* surface central coolant 1 back coolant 2 1000 1100 1050 FW coolant 1 central coolant 2 back wall FW coolant 2 back coolant 1 950 1000 900 950 850 900 850 800 800 bottom middle top 750 750 700 700 0 20 40 60 80 Node number 100 120 0.0 1.0 2.0 3.0 4.0 5.0 Axial distance (m) 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. 18 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 2012. Thermal Stress Analysis in the Bottom Section of the Inboard Blanket 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 Thermal stress distribution 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 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) 19 Thermal Stress Analysis in the Top Section of the Inboard Blanket Max. thermal stress =~118 MPa Pressure stress<~24 MPa Total stresses=~142 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 Max. pressure stress=~42 MPa Thermal stress <52 MPa Total stresses=~94 MPa Thermal stress distribution 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 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 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: http://aries.ucsd.edu/LIB/CAD/FIGURE/ARIES-ACT/ 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.