ML18302A295

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LLC Response to NRC Request for Additional Information No. 502 (Erai No. 9546) on the NuScale Design Certification Application
ML18302A295
Person / Time
Site: NuScale
Issue date: 10/29/2018
From: Rad Z
NuScale
To:
Document Control Desk, Office of New Reactors
Shared Package
ML18302A294 List:
References
AF-1018-62329, RAIO-1018-62328
Download: ML18302A295 (16)
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Text

RAIO-1018-62328 October 29, 2018 Docket No.52-048 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738

SUBJECT:

NuScale Power, LLC Response to NRC Request for Additional Information No.

502 (eRAI No. 9546) on the NuScale Design Certification Application

REFERENCE:

U.S. Nuclear Regulatory Commission, "Request for Additional Information No.

502 (eRAI No. 9546)," dated August 31, 2018 The purpose of this letter is to provide the NuScale Power, LLC (NuScale) response to the referenced NRC Request for Additional Information (RAI).

The Enclosures to this letter contain NuScale's response to the following RAI Questions from NRC eRAI No. 9546:

  • 03.09.02-78
  • 03.09.02-79 Enclosure 1 is the proprietary version of the NuScale Response to NRC RAI No. 502 (eRAI No.

9546). NuScale requests that the proprietary version be withheld from public disclosure in accordance with the requirements of 10 CFR § 2.390. The enclosed affidavit (Enclosure 3) supports this request. Enclosure 2 is the nonproprietary version of the NuScale response.

This letter and the enclosed responses make no new regulatory commitments and no revisions to any existing regulatory commitments.

If you have any questions on this response, please contact Marty Bryan at 541-452-7172 or at mbryan@nuscalepower.com.

Sincerely,

~~

/za~k;ry W. Rad Director, Regulatory Affairs NuScale Power, LLC Distribution: Gregory Cranston, NRC, OWFN-8G9A Samuel Lee, NRC, OWFN-8G9A Marieliz Vera, NRC, OWFN-8G9A NuScale Power, LLC 1100 NE Circle Blvd. , Suite 200 Corvalis, Oregon 97330 , Office: 541.360.0500 , Fax: 541.207.3928 www.nuscalepower.com

RAIO-1018-62328 : NuScale Response to NRC Request for Additional Information eRAI No. 9546, proprietary : NuScale Response to NRC Request for Additional Information eRAI No. 9546, nonproprietary : Affidavit of Zackary W. Rad, AF-1018-62329 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvalis, Oregon 97330, Office: 541.360.0500, Fax: 541.207.3928 www.nuscalepower.com

RAIO-1018-62328 :

NuScale Response to NRC Request for Additional Information eRAI No. 9546, proprietary NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvalis, Oregon 97330, Office: 541.360.0500, Fax: 541.207.3928 www.nuscalepower.com

RAIO-1018-62328 :

NuScale Response to NRC Request for Additional Information eRAI No. 9546, nonproprietary NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvalis, Oregon 97330, Office: 541.360.0500, Fax: 541.207.3928 www.nuscalepower.com

Response to Request for Additional Information Docket No.52-048 eRAI No.: 9546 Date of RAI Issue: 08/31/2018 NRC Question No.: 03.09.02-78 10 CFR 52.47 requires the design certification applicant to include a description and analysis of the structures, systems, and components (SSCs) sufficient to permit understanding of the system designs. 10 CFR 50, Appendix A, GDC 2 requires systems, structures, and components important to safety be designed to withstand appropriate combinations of the effects of normal and accident conditions with the effects of natural phenomena including earthquake. TR-1016-51669-P, "NuScale Power Module Short-Term Transient Analysis," Rev. 0, Section 3.2.3.2, "Flow Acceleration at Break Locations" states that the acoustic elements representing the fluid inside the pipe in the ANSYS blowdown and asymmetric cavity pressurization models and the flow acceleration is applied as a body force to the acoustic element nodes on the break face.

The staff needs to ensure that the input loading is appropriately captured in the blowdown and asymmetric cavity pressurization models, and the description is insufficient for staff to reach a safety finding. Explain how the flow acceleration is converted to body force at the acoustic element nodes on the break face for liquid and steam so that the staff can understand the input loading is appropriately captured in the analysis model.

Include the requested information in the NPM Short-Term Transient Analysis Report or other appropriate documentation in the design certification application.

NuScale Response:

The flow acceleration boundary condition is generated using the NRELAP5 results and saved in a text file for each break location. The flow acceleration boundary condition is applied directly as a body load to the acoustic element break face nodes. For example, the following ANSYS NuScale Nonproprietary

commands are used to read acceleration data from the text file acc.data and apply the acceleration time history to the acoustic element nodes on the break face BreakFace_Nodes.

  • dim,ACC,TABLE,2360,,,TIME
  • tread,ACC,acc,data !Acceleration (m/s^2)

CMSEL,S,BreakFace_Nodes BF,ALL,VELO,%ACC%,0,0 ALLS

The same methods and ANSYS commands are used for the Heissdampf reactor (HDR) benchmarking cases and for the simulated breaches in NuScale pressure boundaries. The simulated HDR boundary conditions and dynamic responses are in agreement with the measured results, as shown in Appendices C, F, and G of TR-1016-51669. Agreement with the experimental results and the consistent method of applying the fluid loads between the benchmarking and design analysis calculations demonstrates that the input loading of the flow acceleration boundary condition is appropriate.

Impact on DCA:

Technical Report TR-1016-51669, NuScale Power Module Short-Term Transient Analysis, has been revised as described in the response above and as shown in the markup provided with the response to question 03.09.02-79.

NuScale Nonproprietary

Response to Request for Additional Information Docket No.52-048 eRAI No.: 9546 Date of RAI Issue: 08/31/2018 NRC Question No.: 03.09.02-79 10 CFR 52.47 requires the design certification applicant to include a description and analysis of the structures, systems, and components (SSCs) sufficient to permit understanding of the system designs. 10 CFR 50, Appendix A, GDC 2 requires systems, structures, and components important to safety be designed to withstand appropriate combinations of the effects of normal and accident conditions with the effects of natural phenomena including earthquake. TR-1016-51669-P, "NuScale Power Module Short-Term Transient Analysis," Rev. 0, Table 6-3, "Case Numbers with Valve Opening or Break Locations" contains seven cases of the axisymmetric pressurization and blowdown analysis. However, no discussion of analysis results is provided in the technical report. SRP 3.9.2 states that staff review of dynamic system analysis covers the methods of analysis, the considerations in defining the mathematical models, the descriptions of the forcing functions, the calculation scheme, the acceptance criteria, and the interpretation of analysis results. The technical report lacks interpretation of analysis results and only provides the bounding values of forces and moments in Table 6-5, "Maximum Forces and Moments at Component Interfaces" and Table 6-6, "Maximum Forces and Moments on Containment Vessel, Reactor Pressure Vessel, Riser, and Core Barrel Assembly" for all the seven pipe break and valve opening cases. The description is insufficient for staff to reach a safety finding. The applicant is requested to identify which are the dominant valve opening cases that attribute to the bounding values of forces and moments in Tables 6-5 and 6-6. Explain why they are the dominant cases. The RCS injection line terminates in the riser, break of RCS injection line will result in a pressure wave traveling internally to the risers. Provide the maximum blowdown loads in the risers due to break of the RCS injection line.

Include the requested information in the NPM Short-Term Transient Analysis Report or other appropriate documentation in the design certification application.

NuScale Nonproprietary

NuScale Response:

Technical Report TR-1016-51669, NuScale Power Module Short-Term Transient Analysis has been revised to correlate the largest forces and moments to the specific valve opening and break location cases for the reactor pressure vessel, reactor vessel internals, and the containment vessel. Tables 6-7 and 6-8 have been added to summarize this information.

Discussion has been added to Section 6.2.4 to explain the results in Tables 6-7 and 6-8.

Additional discussion of the reactor coolant system (RCS) injection line break event results has also been added to Section 6.2.4. Forces and moments in the riser region for that event are provided in Table 6-9.

Impact on DCA:

Technical Report TR-1016-51669, NuScale Power Module Short-Term Transient Analysis, has been revised as described in the response above and as shown in the markup provided in this response.

NuScale Nonproprietary

NuScale Power Module Short-Term Transient Analysis TR-1016-51669-NP Draft Rev. 10 Licensing Topical Report Table 6-5 Maximum forces and moments at component interfaces .................................... 79 Table 6-6 Maximum forces and moments on containment vessel, reactor pressure vessel, riser, and core barrel assembly ............................................................... 80 Table 6-7 Summary of largest forces for RPV, CNV and reactor internals.......................... 81 Table 6-8 Summary of largest moments for RPV, CNV and reactor internals..................... 82 Table 6-9 Force and moment for CVCS injection line break at RPV nozzle........................ 82 FIGURES Figure 2-1 Comparison of NuScale Power Module and Heissdampf reactor ....................... 19 Figure 2-2 Test schematic for Bettis hydraulic pressure pulse (Fig. 4 of Reference 7.2.6) ................................................................................................................... 20 Figure 3-1 NRELAP5 models: example nodalization schematic for Heissdampf reactor experiment .............................................................................................. 25 Figure 3-2 Schematic of the Heissdampf reactor pressure vessel and internals (Fig. 4-1 of Reference 7.2.16) ............................................................................. 26 Figure 3-3 Heissdampf reactor discharge nozzle dimensions and sensor locations (Fig. 6 of Reference 7.2.5) .................................................................................. 28 Figure 3-4 ANSYS finite element analysis model of the Heissdampf reactor pressure vessel and internals .............................................................................. 33 Figure 3-5 ANSYS nozzle end nodes ................................................................................... 35 Figure 3-6 ANSYS finite element analysis model sensor locations ...................................... 39 Figure 3-7 ANSYS finite element analysis model of Bettis hydraulic pressure pulse tests ..................................................................................................................... 44 Figure 3-8 Marviken jet impingement test schematic of test configuration (Figures 2-3 and 2-4 of Reference 7.2.25) ........................................................................ 46 Figure 3-9 NRELAP5 models: example schematics for Marviken experiment ..................... 47 Figure 4-1 Heissdampf reactor V32 depressurization propagation from the break location (at 100 ms) ............................................................................................. 52 Figure 4-2 Heissdampf reactor V32 core barrel deformations (displacement scale factor of 200) ....................................................................................................... 53 Figure 6-1 Schematic for the reactor coolant system subcooled blowdown model .............. 61 Figure 6-2 Flow acceleration boundary condition - chemical and volume control system injection pipe break ................................................................................. 64 Figure 6-3 Thrust force boundary condition - chemical and volume control system injection pipe break ............................................................................................. 65 Figure 6-4 Flow acceleration boundary condition - reactor recirculation valve inadvertent operation ........................................................................................... 66 Figure 6-5 Thrust force boundary condition - reactor recirculation valve inadvertent operation ........................................................................................... 67 Figure 6-6 Schematic for the reactor coolant system saturated blowdown model................ 68 Figure 6-7 Flow acceleration boundary condition- spray and degasification line pipe breaks .......................................................................................................... 69 Figure 6-8 Thrust force boundary condition- spray and degasification line pipe breaks .................................................................................................................. 70 Figure 6-9 Flow acceleration boundary condition- reactor safety valve and reactor vent valve operation ............................................................................................ 70

© Copyright 20186 by NuScale Power, LLC vi

NuScale Power Module Short-Term Transient Analysis TR-1016-51669-NP Draft Rev. 10 Figure 3-5 shows an example pipe break location (which is a portion of the ANSYS model provided in Figure 3-4). Solid elements that represent the pipe wall are shown as light grey nodes. The acoustic elements representing the fluid inside the pipe are shown as dark grey nodes. The flow acceleration is applied as a body force to the acoustic element nodes on the break face.

Figure 3-5 ANSYS nozzle end nodes For example, the following ANSYS commands are used to read acceleration data from the text file acc.data and apply the acceleration time history to the acoustic element nodes on the break face BreakFace_Nodes.

  • dim,ACC,TABLE,2360,,,TIME
  • tread,ACC,acc,data !Acceleration (m/s^2)

CMSEL,S,BreakFace_Nodes BF,ALL,VELO,%ACC%,0,0 ALLS

© Copyright 20186 by NuScale Power, LLC 35

NuScale Power Module Short-Term Transient Analysis TR-1016-51669-NP Draft Rev. 10 Table 6-6 Maximum forces and moments on containment vessel, reactor pressure vessel, riser, and core barrel assembly Location and Maximum Maximum Maximum Component Elevation Horizontal Vertical Moment Section ID (inches) Force, FX Force, FY MZ (lbf) (lbf) (in-lbf) 1 CNV - Elevation 37.8 ((

2 CNV - Elevation 138.5 3 CNV - Elevation 179.9 4 CNV - Elevation 328.3 5 CNV - Elevation 500.9 6 CNV - Elevation 673.0 7 CNV - Elevation 816.0 8 CNV - Elevation 834.8 9 RPV - Elevation 22.1 10 not used 11 RPV - Elevation 91.9 12 RPV - Elevation 160.6 13 RPV - Elevation 270.8 14 RPV - Elevation 352.3 15 RPV - Elevation 402.5 16 RPV - Elevation 540.1 17 RPV - Elevation 625.5 18 RPV - Elevation 671.0 19 Lower Riser - Elevation 158.3 20 Lower Riser - Elevation 236.3 21 Core Barrel - Elevation 47.3 22 Core Barrel - Elevation 142.32(a),(c),ECI Table 6-7 identifies the largest five forces, acting in any one direction, and Table 6-8 identifies the five largest moments. The valve opening or break location associated with each of the forces and moments is identified. The highest two forces and moments on the reactor internals and CNV are also listed but are much lower than for the RPV. Unlike the RPV, these components do not experience the dynamic thrust loading associated with the valve actuations and therefore have lower overall forces and moments due to only the propagating pressure waves. All of the largest forces act in the Y direction and generally, the forces in the Y direction are greater than in the X and Z directions at any location for a particular case. The exceptions for this are at the lower RPV head, the core support blocks, and in the lower riser. These three © Copyright 20186 by NuScale Power, LLC 80

NuScale Power Module Short-Term Transient Analysis TR-1016-51669-NP Draft Rev. 10 regions do not bear the load from the pressure wave traveling vertically inside the RPV and therefore experience comparable or higher lateral forces than vertical for the cases analyzed. The five largest forces result from the actuation of two RVVs and occur within the RPV, from the region just below the RPV flange up to the RPV shell adjacent to the bottom 1/3 portion of the steam generator. The scenario of two RVVs actuating at normal operating pressure and temperature conditions is beyond design basis for safety analysis; however it is analyzed for mechanical design to provide a conservative estimate of the possible blowdown loading conditions. Two RVVs actuating simultaneously provides the largest forces due to the high mass flow rates and correspondingly high fluid accelerations generated by this event. The five largest moments generated by the scenarios analyzed come from both the two-RVV case and the case where one RVV and one RRV are assumed to actuate simultaneously. The largest forces and moments act on the RPV. For the case of the simultaneous RVV and RRV actuation, two pressure waves form in different locations and travel through the RPV. This case produces the two highest-magnitude moments, localized in the vicinity of the RPV support skirt. These high moments are due to the torque applied to the RPV by the thrust load from an RVV and RRV actuating on the same side of the RPV, unopposed by any valve discharge on the other side of the vessel. The region of the RPV with the highest forces corresponds to the locations with the highest moments for these events. Table 6-7 Summary of largest forces for RPV, CNV and reactor internals Force Corresponding Interface/Support Location FY (lbf) Event Largest Forces (acting on RPV) RPV - Elevation 270.8 (( RPV - Elevation 352.3 RPV - Elevation 402.5 2 RVVs RPV Flange RPV - Elevation 160.6 }}2(a),(c) Largest Forces on Reactor Internals Core Barrel / Reflector - Elevation 141.8 (( 2 RVVs Core Barrel / Reflector - Elevation 47.3 }}2(a),(c) Largest Forces on CNV CNV Skirt (( 2 RVVs CNV - Elevation 37.8 }}2(a),(c) © Copyright 20186 by NuScale Power, LLC 81

NuScale Power Module Short-Term Transient Analysis TR-1016-51669-NP Draft Rev. 10 Table 6-8 Summary of largest moments for RPV, CNV and reactor internals Moment Corresponding Interface/Support Location MZ (in*lbf) Event Largest Moments (all acting on RPV) RPV Support Skirt (( 1 RRV + 1 RVV RPV - Elevation 540.1 RPV - Elevation 160.6 RPV Flange 2 RVVs RPV - Elevation 270.8 }}2(a),(c) Largest Moments on Reactor Internals Core Barrel / Reflector - Elevation 47.3 (( 2 RVVs Riser Transition }}2(a),(c) Largest Moments on CNV CNV - Elevation 500.9 (( 1 RVV CNV Flange }}2(a),(c) The highest force and moment for the CVCS injection line break is located at the same elevation on the RPV as the highest force for the case of two RVVs actuating simultaneously (elevation 270.8 inches), which is approximately 50 inches below the SG tube support cantilever. Table 6-9 provides the loads on reactor internals, including riser locations near to where the pressure wave originates. The forces near the riser location for this event are smaller than are experienced for the case of the double RVV actuation per Table 6-7. For the CVCS injection line break event, the forces and moments on many parts of the RPV and reactor vessel internals are close in magnitude; implying that the pressure wave imparts similar forces on the structures. The case of the pressure wave originating from the upper riser assembly is not bounding for mechanical design. Table 6-9 Forces and moments for CVCS injection line break at RPV nozzle Force Moment Interface/Support Location FY (lbf) MZ (in*lbf) Largest Force and Moment (acting on RPV) RPV - Elevation 270.8 (( }}2(a),(c) Forces and Moments on Riser Locations Lower Riser- Elevation 147.3 (( Lower Riser - Elevation 158.3 Riser Transition Upper Riser Hanger }}2(a),(c) © Copyright 20186 by NuScale Power, LLC 82

RAIO-1018-62328 : Affidavit of Zackary W. Rad, AF-1018-62329 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvalis, Oregon 97330, Office: 541.360.0500, Fax: 541.207.3928 www.nuscalepower.com

NuScale Power, LLC AFFIDAVIT of Zackary W. Rad I, Zackary W. Rad, state as follows:

1. I am the Director, Regulatory Affairs of NuScale Power, LLC (NuScale), and as such, I have been specifically delegated the function of reviewing the information described in this Affidavit that NuScale seeks to have withheld from public disclosure, and am authorized to apply for its withholding on behalf of NuScale.
2. I am knowledgeable of the criteria and procedures used by NuScale in designating information as a trade secret, privileged, or as confidential commercial or financial information. This request to withhold information from public disclosure is driven by one or more of the following:
a. The information requested to be withheld reveals distinguishing aspects of a process (or component, structure, tool, method, etc.) whose use by NuScale competitors, without a license from NuScale, would constitute a competitive economic disadvantage to NuScale.
b. The information requested to be withheld consists of supporting data, including test data, relative to a process (or component, structure, tool, method, etc.), and the application of the data secures a competitive economic advantage, as described more fully in paragraph 3 of this Affidavit.
c. Use by a competitor of the information requested to be withheld would reduce the competitor's expenditure of resources, or improve its competitive position, in the design, manufacture, shipment, installation, assurance of quality, or licensing of a similar product.
d. The information requested to be withheld reveals cost or price information, production capabilities, budget levels, or commercial strategies of NuScale.
e. The information requested to be withheld consists of patentable ideas.
3. Public disclosure of the information sought to be withheld is likely to cause substantial harm to NuScale's competitive position and foreclose or reduce the availability of profit-making opportunities. The accompanying Request for Additional Information response reveals distinguishing aspects about the method by which NuScale develops its power module short term transient analysis.

NuScale has performed significant research and evaluation to develop a basis for this method and has invested significant resources, including the expenditure of a considerable sum of money. The precise financial value of the information is difficult to quantify, but it is a key element of the design basis for a NuScale plant and, therefore, has substantial value to NuScale. If the information were disclosed to the public, NuScale's competitors would have access to the information without purchasing the right to use it or having been required to undertake a similar expenditure of resources. Such disclosure would constitute a misappropriation of NuScale's intellectual property, and would deprive NuScale of the opportunity to exercise its competitive advantage to seek an adequate return on its investment. AF-1018-62329

4. The information sought to be withheld is in the enclosed response to NRC Request for Additional Information No. 502, eRAI 9546. The enclosure contains the designation "Proprietary" at the top of each page containing proprietary information. The information considered by NuScale to be proprietary is identified within double braces, "(( }}" in the document.
5. The basis for proposing that the information be withheld is that NuScale treats the information as a trade secret, privileged, or as confidential commercial or financial information. NuScale relies upon the exemption from disclosure set forth in the Freedom of Information Act ("FOIA"), 5 USC§ 552(b)(4), as well as exemptions applicable to the NRC under 10 CFR §§ 2.390(a)(4) and 9.17(a)(4).
6. Pursuant to the provisions set forth in 10 CFR § 2.390(b )(4 ), the following is provided for consideration by the Commission in determining whether the information sought to be withheld from public disclosure should be withheld:
a. The information sought to be withheld is owned and has been held in confidence by NuScale.
b. The information is of a sort customarily held in confidence by NuScale and, to the best of my knowledge and belief, consistently has been held in confidence by NuScale.

The procedure for approval of external release of such information typically requires review by the staff manager, project manager, chief technology officer or other equivalent authority, or the manager of the cognizant marketing function (or his delegate), for technical content, competitive effect, and determination of the accuracy of the proprietary designation. Disclosures outside NuScale are limited to regulatory bodies, customers and potential customers and their agents, suppliers, licensees, and others with a legitimate need for the information, and then only in accordance with appropriate regulatory provisions or contractual agreements to maintain confidentiality.

c. The information is being transmitted to and received by the NRC in confidence.
d. No public disclosure of the information has been made, and it is not available in public sources. All disclosures to third parties, including any required transmittals to NRC, have been made, or must be made, pursuant to regulatory provisions or contractual agreements that provide for maintenance of the information in confidence.
e. Public disclosure of the information is likely to cause substantial harm to the competitive position of NuScale, taking into account the value of the information to NuScale, the amount of effort and money expended by NuScale in developing the information, and the difficulty others would have in acquiring or duplicating the information. The information sought to be withheld is part of NuScale's technology that provides NuScale with a competitive advantage over other firms in the industry.

NuScale has invested significant human and financial capital in developing this technology and NuScale believes it would be difficult for others to duplicate the technology without access to the information sought to be withheld. I declare under penalty of perjury that the foregoing is true and correct. Executed on October 29, 2018. AF-1018-62329}}

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