LR-N17-0186, Response to Request for Additional Information Regarding License Amendment Request for Measurement Uncertainty Recapture Power Uprate

From kanterella
(Redirected from ML17353A926)
Jump to navigation Jump to search

Response to Request for Additional Information Regarding License Amendment Request for Measurement Uncertainty Recapture Power Uprate
ML17353A926
Person / Time
Site: Hope Creek PSEG icon.png
Issue date: 12/19/2017
From: Carr E
Public Service Enterprise Group
To:
Document Control Desk, Office of Nuclear Reactor Regulation
Shared Package
ML17353A925 List:
References
CAC MF9930, LAR H17-03, LR-N17-0186
Download: ML17353A926 (58)
v • d • e


Text

Enlcosure 3 Contains Proprietary Information to be Withheld from Public Disclosure Pursuant to 10 CFR 2.390 PSEG Nuclear LLC P.O. Box 236, Hancocks Bridge, NJ 08038-0236 PSEG N-uclearLLC 10 CFR 50. 90 OEC 19 2017 LR-N17-0186 LAR H17-03 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Hope Creek Generating Station Renewed Facility Operating License No. NPF-57 NRC Docket No. 50-354

Subject:

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR MEASUREMENT UNCERTAINTY L RECAPTURE POWER UPRATE (CAC NO. MF9930)

References 1. PSEG letter to NRC, "License Amendment Request for Measurement Uncertainty Recapture (MUR) Power Uprate," dated July 7, 2017 (ADAMS Accession No. ML17188A260)

2. NRC e-mail to PSEG, "Final Request for Additional Information - Steam Dryer Analysis for Hope Creek MUR," dated December 14, 2017 (ADAMS Accession No ML17348A997)

In the Reference 1 letter, PSEG Nuclear LLC (PSEG) submitted a license amendment request for Hope Creek Generating Station (HCGS). The proposed amendment will increase the rated thermal power (RTP) level from 3840 megawatts thermal (MWt) to 3902 MWt, and make Technical Specification (TS) changes as necessary to support operation at the uprated power level.

In Reference 2, the U.S. Nuclear Regulatory Commission staff requested PSEG to submit the document COl Technical Note (TN)16-23P to support the NRC review of Reference 1.

This letter provides a non-proprietary version of the requested document in Enclosure 1 and a proprietary version in Enclosure 3.

Enclosure 3 Contains Proprietary Information to be Withheld from Public Disclosure Pursuant to 10 CFR 2 . 390 Page 2 10 CFR 50.90 LR*N17-0186 Enclosure 3 contains proprietary information as defined by 10 CFR 2.390. Continuum Dynamics, Inc. (CD I), as the owner of the proprietary information, has executed an affidavit (provided in Enclosure 2) identifying that the proprietary information has been handled and classified as proprietary, is customarily held in confidence, and has been withheld from public disclosure. CDI requests that the proprietary information in Enclosure 3 be withheld from public disclosure, in accordance with the requirements of 10 CFR 2.390(a)(4).

PSEG has determined that the information provided in this submittal does not alter the conclusions reached in the 10 CFR 50.92 no significant hazards determination previously submitted. In addition, the information provided in this submittal does not affect the bases for concluding that neither an environmental impact statement nor an environmental assessment needs to be prepared in connection with the proposed amendment.

No new regulatory commitments are established by this submittal. If you have any questions or require additional information, please do not hesitate to contact Mr. Brian Thomas at (856) 339-2022.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on /;)_/fc-f //7-*

' (Date)

Respectfully, C::-*----2------*--*****

Eric Carr Site Vice President Hope Creek Generating Station

Enclosure 3 Contains Proprietary Information to be Withheld from Public Disclosure Pursuant to 10 CFR 2.390 DEC 19 2017 Page 3 10 CFR 50.90 LR-N17-0186 Attachment

1. Response to EMIB Request for Additional Information Regarding MUR Power Uprate Enclosures
1. COl Technical Note (TN) 16-23NP, Stress Evaluation of Hope Creek Unit 1 Steam Dryer at MUR Conditions Using Perforated Plate Damping - Non-Proprietary
2. COl Affidavit supporting the withholding of information in Enclosure 3 from public disclosure
3. COl Technical Note (TN)16-23P, Stress Evaluation of Hope Creek Unit 1 Steam Dryer at MUR Conditions Using Perforated Plate Damping - Proprietary cc: Mr. D. Dorman, Administrator, Region I, NRC Ms. L. Regner, Project Manager, NRC NRC Senior Resident Inspector, Hope Creek Mr. P. Mulligan, Chief, NJBNE Mr. L. Marabella, Corporate Commitment Tracking Coordinator Mr. T. MacEwen, Hope Creek Commitment Tracking Coordinator LAR H17-03 LR-N17-0186 Response to EMIB Request for Additional Information Regarding MUR Power Uprate

Attachment 1 LAR H17-03 LR-N17-0186 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST FOR MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE PSEG NUCLEAR LLC (PSEG)

HOPE CREEK GENERATING STATION (HOPE CREEK)

DOCKET NO. 50-354 By letter dated July 07, 2017 (Agencywide Documents Access and Management System Accession No. ML17188A260), PSEG Nuclear LLC (the licensee) submitted a License Amendment request for Hope Creek Generating Station (Hope Creek). The amendment would revise the Renewed Facility Operating Licenses (RFOLs) and Technical Specifications (TSs) to implement a measurement uncertainty recapture (MUR) power uprate. Specifically, the amendments would authorize an increase in the maximum licensed thermal power level from 3, 840 megawatts thermal (MWt) to 3, 902 MWt, which is an increase of approximately

1. 61 percent above the current thermal power, or an increase of 19 percent above the original licensed thermal power (3293 MWt. ).

To complete its review, the Nuclear Regulatory Commission (NRC) staff requests the following additional information.

EMIB-01 In enclosure 1 to LAR H17 -03, Section 3. 4. 2 on Adverse Flow Effects, the licensee references steam dryer stress analysis document, but this document was not provided to the NRC. The steam dryer analysis reveals the low margin due to an Acoustic Circuit Model (ACM) code error discovered in 2015. The licensee is requested to provide the document, CDI Technical Note (TN)16-23P, "Steam Dryer Analysis" on the docket for NRC review and to allow the NRC staff to reach a safety conclusion regarding the continued structural integrity of the steam dryer and verify the margin for high cycle fatigue stresses due to adverse flow effects.

'" **Pd'§PONSE:

Non-proprietary and proprietary versions of CDI Technical Note (TN)16-23P are provided in Enclosures 1 and 3 of this letter respectively.

1 of 1 LAR H17-03 LR-N17-0186 CDI Technical Note (TN) 16-23NP, Stress Evaluation of Hope Creek Unit 1 Steam Dryer at MUR Conditions Using Perforated Plate Damping Non-Proprietary This is the non-proprietary version of Enclosure 3 of this letter which has the proprietary information removed. Portions of the document that have been removed are indicated by white space inside open and closed brackets as shown here (( (3l)).

This document does not contain Continuum Dynamics, Inc. Proprietary Information Executive Summary The stresses on the Hope Creek steam dryer are calculated at MUR conditions with the effect of perforated plate damping (PPD) taken into account. ((

(3)))

The current stress evaluation does not include the effect known as ((

(3))); a stress evaluation with this effect is given in [2]. Exce pt for the inclusion of PPD and the evaluation at MUR rather th an CLTP conditions, the stress as sessment is identical to that reported in [3]. These stre ss predictions account for all the end-to-end biases and uncertainties in the loads m odel [4] and fi nite element analysis [5]. To account for frequency uncertainties in the fini te element model, the stresses are also computed for loads that are shifted in the frequency dom ain between 10% in 2.5% increm ents. From this assessm ent the limiting stress ratios obtaine d at CLTP and MUR, with and without PPD in the HC1 steam dryer are as follows:

Minimum Stress Ratio Minimum Stress Ratio Load PPD No Freq. Shifting with Freq. Shifting SR-P SR-a SR-P SR-a CLTP None 1.33 1.12 1.27 1.07 MUR None 1.33 1.08 1.26 1.04 CLTP 42.5% 1.33 1.14 1.27 1.08 MUR 42.5% 1.33 1.10 1.26 1.05 The minimum alternating stress ratio increases from SR-a=1.04 to SR-a=1.05 when PPD is applied. At other locations w ith SR-a<2, stress reductions of up to 2.6% are observed; when considering the loca tions with SR-a<5, stress reductions of up to 23% are noted. These reductions are consistent with those at other pl ants, but do not occur at the lim iting location for the HC1 dryer. The limiting location is the same both with and without PPD and lies on the weld connecting the backing bar to the middle hood. All stress ratios meet the ASME code allowable.

ii

This document does not contain Continuum Dynamics, Inc. Proprietary Information Table of Contents Section Page Executive Summary ........................................................................................................................ ii Table of Contents ........................................................................................................................... iii Nomenclature ................................................................................................................................. iv

1. Introduction & Approach Overview ........................................................................................... 1 1.1 Perforated Plate Damping Model.......................................................................................... 2
2. Stresses at MUR Using PPD ....................................................................................................... 5 2.1 General Stress Distribution and High Stress Locations ........................................................ 5 2.2 Load Combinations and Allowable Stress Intensities ........................................................ 14 2.3 Frequency Content and Sensitivity to Frequency Shift of the Stress Signals ..................... 29
3. Comparison of Stresses With and Without PPD....................................................................... 39
4. Conclusions ............................................................................................................................... 44
5. References ................................................................................................................................. 45 iii

This document does not contain Continuum Dynamics, Inc. Proprietary Information Nomenclature ACM acoustic circuit model ASME American Society of Mechanical Engineers B&PV Boiler and Pressure Vessel CDI Continuum Dynamics, Inc.

CLTP current licensed thermal power EPU extended power uprate fsw weld factor HC1 Hope Creek Unit 1 MASR minimum alternating stress ratio MSL main steam line MUR measurement uncertainty recovery NRC Nuclear Regulatory Commission Pb bending stress intensity Pm membrane stress intensity PPD perforated plate damping PSD power spectral density RMS root mean square RPS reduced point set Sa service limit for alternating stress intensity Salt alternating stress intensity Sm service limit for membrane stress intensity SR-a alternating stress ratio SR-P peak stress ratio USR upper support ring

(( (3)))

WF weld factor 1D one-dimensional iv

This document does not contain Continuum Dynamics, Inc. Proprietary Information

1. Introduction & Approach Overview The steam dryer loads d ue to acoustic pressu re fluctuations in the m ain steam lines (MSLs) are potentially damaging and the cyclic stresses from these loads can produce fatigue cracking if loads are sufficiently high. The industry has ad dressed this problem with physical modifications to the dryers, as well as a program to define st eam dryer loads and their resulting stresses. The present report evaluates the stress es for the H ope Creek Unit 1 (HC1) n uclear plant steam dryer at the planned Measurem ent Uncertainty Reco very (MUR) condition, which corresponds to a power increase relative to CLTP of, at most, 1.72%.

The present stress analysis complements and differs from prior stress assessments of the HC1 dryer by accounting for the effect of perforated plate damping (PPD), which has been included in the stress analysis for other plants (e.g., [6] & [7]), but not for the HC1 dryer. In [3], an identical stress analysis was carried out for CLTP c onditions that o mitted PPD and yielded a m inimum alternating stress ratio (MASR) of 1.07. Scaling this result to MUR conditions estim ates a MASR of 1.04, which while above the ASME lim it of 1.0, warrants consideration of alternate methods that account for known dissipation mechanisms. The hope is to increase margin and/or restrict high stress locations to sites or welds that can be readily inspected. In [2] ((

(3))).

PPD arises when a perforated plate experien ces vibration along its norm al direction while simultaneously subject to steady state flow through the perforation holes. In steam dryers this situation arises for the plates imm ediately ahead (inlet) and aft (ex it) of the vane bank assemblies. The force is proportional to the product of the mean velocity through the perforation holes and n ormal plate velocity. It therefore ac ts as a resistive force and increas es with the approach velocity and inverse of o pen area ratio. Since the use of PPD was perm itted under previous steam dryer assessm ents for power upr ates [6, 7] its use is reason able for th e comparatively smaller HC1 MUR uprate. Note that the contributions of perforated plate damping were also quantified by experim ent [8] and only 42.5% of the theoretical P PD is used which is also well below the levels observed in experiment. PPD mainly affects the response of the perforated plates and parts to which they are attached such as the hood supports and vane bank support. For the HC1 unit at CLTP, th e limiting MASR locations involve the hood and hood supports; hence P PD is expected to alleviate stresses on those parts. Other high stress locations occurring on the drain channel/skirt welds are located further away from the perforated plates and any changes in stress at these locatio ns are expected to be s mall. These welds are readily accessible for in spection and have not experienced dam age to date, despite 8+ years of operation at CLTP.

The load combination considered here corresponds to normal operation (the Level A Service Condition) and includes fluctuatin g pressure loads developed fr om HC1 m ain steam line data ,

and weight. Level B service conditions, which in clude seismic loads, are not included in this evaluation. The fluctuating pressure loads, indu ced by the flowing steam , are predicted at the 1

This document does not contain Continuum Dynamics, Inc. Proprietary Information CLTP condition using a separate acoustic circuit analysis of the steam dome and m ain steam lines [9]. MUR stress es are estimated by simple scaling of the flow-indu ced CLTP stresses by velocity squared or, in this case, 1.0172 2=1.035. A potential for resona nces exists at both CLTP and MUR conditions and so the bias and uncertainty for a resonant peak have been applied to the loads over the 116-120 Hz frequency interval over which a putative resonance would emerge.

The stress analysis is carried ou t in the frequency domain, which confers a num ber of useful computational advantages over a tim e-accurate transient analysis including the ability to assess the effects of frequency scaling in the loads without the need for addition al finite elem ent calculations. For additional deta ils of this approach as well as of the HC1 finite elem ent model, the manner in which the acoustic loads are applied to the dryer, the post-processing of the results to obtain stress intensities and s tress ratios suitably adjusted at weld s to estab lish compliance with the AS ME B&PV Code (Section III, sub section NG) [10], the reader is referred to [3].

Except for the application of PPD and scaling to MUR conditions the stress evaluation is performed in the sam e manner as in [3]. Add itional details of PPD ap plied to the HC1 steam dryer are provided below.

Section 2 summarizes the stress results using PPD by tabulating the highest m aximum and alternating stress intensities and p resenting contour plots of these st resses to ind icate which points on the dryer experience sign ificant stress concentration a nd/or modal response (Section 2.1). Comparisons of the stresses against allowable values, accounting for stress type (maximum and alternating) and location (on or away from a weld) are also provided in terms of stress ratios in Section 2.2. Section 2.3 exam ines the spectr al content of select nodes and the dom inant frequency distribution over the dryer. Section 3 compares the stresses with and without PPD. It is shown that while at some locations near the perforated plates the stress are reduced by more than 20%, the lim iting stress locations only change by about 1%. The lim iting maximum and alternating stress ratios at MU R are estimated as SR-P=1.26 and SR-a=1.05. The overall stress distributions and their frequency content with and without PPD are found to be similar.

1.1 Perforated Plate Damping Model

((

(1)

(2)

(3)

(3)

))

2

This document does not contain Continuum Dynamics, Inc. Proprietary Information

((

(3)

))

3

This document does not contain Continuum Dynamics, Inc. Proprietary Information

((

(3)

))

Figure 1. ((

(3)

))

Table 1. Damping properties of perforated plates.

((

(3)

))

4

This document does not contain Continuum Dynamics, Inc. Proprietary Information

2. Stresses at MUR Using PPD The present section rep orts the stresses obtained when PPD is used. Results are presented both at nominal conditions (no frequency shift) and with frequency shift included. As done in

[3], frequency shifts are perfor med at 2.5% increm ents. The eff ects of frequency shifts can be conservatively accounted for by identifying the maximum stress (Section 2.1) or minimum stress ratio (Section 2.2) at every node , where the m inimum is taken over all the frequency shifts considered (including the nom inal or 0% shift ca se). The stress tables also report the dom inant frequencies in the stress response estim ated by identifying the Fourier coefficient with the biggest amplitude. When frequency shifting is performed the pre-shift frequency is reported; so, for example, a reported 50 Hz frequency with +10% frequency shift corresponds to a stress response peak at 55 Hz.

The tabulated stresses and stress ratios are ob tained using a ' blanking' procedure that is designed to prevent reporting a large num ber of high stress nodes from essentially the sam e location on the structure. Details of the blanking process are given in S ection 5 of [3]. Here i t suffices to note that a no de appearing in the stress table actually represents the limiting stress or stress ratio within a 10 inch ne ighborhood and its 3 mirror images across the x- and y- symmetry planes.

2.1 General Stress Distribution and High Stress Locations The maximum stress intensities obtained by post-processing the ANSYS stress histories for MUR at nominal frequency and with f requency shift operating conditions are listed in Table 2.

Contour plots of the stress intensities over th e steam dryer structure are shown in Figure 2 (maximum stress over all nine frequency shifts including nominal). The fi gures are oriented to emphasize the high stress regions. Note that these stress intensities do not account for weld factors but do include end-to-end bias and uncertain ty. Further, it should be noted that since the allowable stresses vary with locatio n, stress intensities do not necessarily correspond to regions of primary structural concern. Instead, structural evaluation is more accurately made in terms of the stress ratios which compare the computed stresses to allowable levels with due account made for stress type and weld factors. Comparisons on the basis of stre ss ratios are made in Section 2.2.

The general stress state in term s of stress inte nsities and lo w stress r atio locations is ver y similar to the ones reported previously for CLTP without PPD [3]. For the peak stresses, Pm and Pm+Pb, many of the nodes are dom inated by the st atic component which does not change with the acoustic loads. The m aximum stress intensities in most areas are low (less than 500 psi, or 5% of the most conservative critical stress ). For the m embrane stresses (Pm ) the high stress regions tend to occur at: (i) the inner hoods; (ii) the outermost portion of the inner hood near the connection to the closure plate; (iii) the weld joining the skirt and the upper support ring near the supports; and (iv) the central base plate/vane bank junction. For most locations the stress is dominated by static stresses as evidenced by the sm all alternating stresses in the rightm ost columns in the table. The closure plates and re gions in the vicinity of where they connect to adjacent hoods or vane banks, experience high stre sses since they restrain any deflection of th e adjacent vane banks.

5

This document does not contain Continuum Dynamics, Inc. Proprietary Information The membrane + bending stress (P m+Pb) distributions show a pronounced m odal response pattern, notably over the drain channels. Howeve r, except for the drain channel/skirt welds the highest stress locations are still dom inated by the static component as confirmed by comparing the Pm+Pb and Salt colum ns in Table 2. Stre ss concentrations are visible near the hood supports, at the bottoms of the hoods, near the tops of the closure plates and along the skirt/drain channel welds.

The highest alternating stress without freque ncy shifting is 6243 psi occurring on the weld joining the middle hood and backing bar. This increases to 6566 psi when frequency shifting is included with the lim iting shift being +2.5%. Th e highest alternating st ress intensity at a non-weld location is 6444 psi on the inner hood (with frequency shiftin g). The alternating stress intensity contour plots in Figure 2d-e essentially record the modes excited by this signal, which here are seen to primarily involve the inner and middle hoods which, though not directly exposed to the main MSL pressure fluctuations (like the outer hoods are) are of th inner construction and therefore exhibit a significant response.

6

This document does not contain Continuum Dynamics, Inc. Proprietary Information Table 2a. Locations with highest predicted stress intensities at MUR and PPD - no frequency shift.

Stress Location Location (in) Stress Intensities (psi) Dom.

Category Weld x y z node Pm Pm+Pb Salt Freq. (Hz)

Pm Hood No 109 27.6 95.3 44886 6764 9587 1310 46.7

" Backing Bar/Hood Support/Mid Cover Plate Yes 0 38.4 7.5 79684 5068 5126 2779 48.7

" Inner Side Panel/Vane Bank/Mid Cover Plate Yes 118.8 14.4 7.5 85994 4593 6335 868 46.9

" Hood Support/Mid Cover Plate/Backing Bar Yes 59.5 38.4 7.5 86958 4523 4722 2512 47.7

" Skirt/Skirt Ext Yes 118.7 5.9 2 91960 4459 6526 1053 47.7 Pm+Pb Skirt/Cap Strip/Skirt Ext Yes 118.8 0.6 2 88325 2579 10505 1671 46.8

" Hood No 109 27.6 95.3 44886 6764 9587 1310 46.7

" Backing Bar/Hood Yes 29.1 69.9 8.5 87919 732 6673 6243 49.0

" Drain Channel/Bottom Skirt Yes 118.2 12 94.2 90843 1761 6666 4001 31.7

" Drain Channel/Bottom Skirt Yes 73.8 93.1 94.2 90834 2216 6502 4226 47.3 Salt Backing Bar/Hood Yes 29.1 69.9 8.5 87919 732 6673 6243 49.0

" Hood No 30.2 68.9 35.2 37937 1242 5583 5297 49.0

" Backing Bar/Hood Yes 29.5 38.4 8.5 85224 681 5532 5200 47.7

" Hood No 28.4 67.3 52.2 37238 1430 5502 5194 49.0

" Hood No 24.2 64.9 69 37916 1330 5486 5157 49.0 7

This document does not contain Continuum Dynamics, Inc. Proprietary Information Table 2b. Locations with highest predicted stress intensities taken over all frequency shifts at MUR and PPD.

Stress Location Weld Location (in) Stress Intensities (psi) % Freq. Dom.

Category x y z node Pm Pm+Pb Salt Shift Freq. (Hz)

Pm Hood No 109 27.6 95.3 44886 6842 9587 1377 10 48.7

" Hood Support/Mid Cover Plate/Backing Bar Yes 0 38.4 7.5 86960 5368 5418 3169 10 48.6

" Hood Support/Vane Bank/Mid Cover Plate Yes 0 22.9 7.5 93159 5264 5299 3949 10 36.8

" KT1444/Hood Yes 109.8 38.4 9.5 92106 5027 5028 2549 10 48.6

" Skirt/Skirt Ext Yes 118.7 5.9 2 91960 4919 7152 1498 5 48.7 Pm+Pb Skirt/Cap Strip/Skirt Ext Yes 118.8 0.6 2 88325 2951 11048 1996 2.5 22.4

" Hood No 109 27.6 95.3 44886 6842 9587 1377 0 48.7

" Bottom Skirt/Drain Channel Yes 73.8 93.1 94.2 93833 2319 8247 5988 10 28.4

" Drain Pipe/Skirt Yes 88.2 79.6 20.5 91083 2718 7665 2284 10 48.7

" Bottom Skirt/Drain Channel Yes 118.2 12 94.2 93758 2266 7416 4925 5 47.3 Salt Backing Bar/Hood Yes 29.1 69.9 8.5 87919 923 6983 6566 2.5 47.7

" Hood No 83.4 35.9 50.9 40188 3727 6843 6444 10 48.7

" Backing Bar/Hood Yes 30 38.4 8.5 88060 1258 6630 6194 2.5 48.6

" Hood Support/Hood Yes 0 36.1 49.6 80664 2793 6558 6148 10 36.8

" Bottom Skirt/Drain Channel Yes 73.8 93.1 94.2 93833 2319 8247 5988 10 28.4 8

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 2a. Contour plot of m aximum membrane stress intensity, Pm , for MUR with frequency shifts. The recorded stress at a node is the maximum value taken over all frequency shifts. The maximum stress intensity is 6,842 psi.

9

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 2b. Contour plot of m aximum membrane+bending stress intensity, Pm +Pb, for MUR with frequency shifts. The recorded stress at a node is the m aximum value taken over all frequency shifts. The maximum stress intensity is 11,048 psi. First view.

10

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 2c. Contour plot of maximum membrane+bending stress intensity, Pm+Pb, for MUR with frequency shifts. This second view from beneath reveals high stress and modal response of the hood/hood support junctions.

11

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 2d. Contour plot of alternating stress intensity, S alt, for MUR with frequency shifts. The recorded stress at a nod e is the m aximum value taken over all frequency shifts. The m aximum alternating stress intensity is 6,566 psi. First view.

12

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 2e. Contour plot of alternating stress intensity, S alt, for MUR with frequency shifts. This second view from beneath reve als more of the high stress regions on the hood/hood support junctions.

13

This document does not contain Continuum Dynamics, Inc. Proprietary Information 2.2 Load Combinations and Allowable Stress Intensities The stress ratios com puted for MUR at nom inal frequency (no freque ncy shift) and with frequency shifting are listed in Table 3 and Ta ble 4 respectively. The stress ratios are grouped according to type (SR-P for m aximum membrane and m embrane+bending stress, SR-a for alternating stress) and location (away from welds or on a weld). At nom inal frequency shift the minimum peak stress ratio, SR-P=1.33, and occurs at the junction of the skirt and USR. At this condition, the dryer stress state is effectively govern ed by the weight-induced static stress field.

This is clear from Table 3b where the correspo nding alternating stress ra tio is SR-a=4.11. The limiting peak stress ratio SR-P=1.26, occurs with th e -2.5% shift and occurs at the sam e location as with no frequency shift. In [3], the limiting peak stress ratio also occurred at this location with SR-P=1.27 at CLTP, and had the same dominant 22.4 Hz frequency.

The minimum alternating stress ratio at any frequency shift, SR-a=1.05, occurs on the weld joining the bottom of the middle hood and backing bar. A similar stress state occurs on the inner hood/backing bar weld with SR-a=1.11. The third and fifth lowest alternating stress ratios occur on the inner hood/hood support junction. The fourth lowest alternating stress ratio is SR-a=1.15 and occurs at the bo ttom of the drain channel/sk irt weld. These f ive locations comprise three distinct weld configurations: (a) hood/back ing bar weld; (b) hood/hood support weld and (c) drain channel/skirt weld. All of the f irst 21 limiting alternating stress ratio locations with SR-a1.71 fall into one of these three categories. These are depicted in Figure 3f-h which identifies the 21 lim iting nodes listed in Table 4c and al so displays all nodes with SR-a<4 without blanking. The limiting alternating stress ratios with and without frequency shifts (SR-a=1.10 and 1.05 respectively) differ by less than 5%. Tabl e 4d shows the rem aining RPS locations with alternating stress ratios below 2.0 which introduces two new distin ct weld configurations each having limiting SR-a=1.74. These are: (d) the weld connecting the inner hood and outer plenum plate (also referred to as the closure plate) (location 23); and (e) the junction between the inner vane bank/hood support/inner base plate (location 22). Virtually all locations are characterized by a dom inant frequency occurri ng at either at 36.8 Hz or in the narrow range 47.7-48.7 Hz.

These signals are prominent in the acoustic loads.

These observations closely follow those in [3] without PPD; further comparisons between the results with and without PPD are presented in Section 4.

14

This document does not contain Continuum Dynamics, Inc. Proprietary Information Table 3a. Limiting non-weld locations at MUR with no frequency sh ift. Stress ratios are grouped according to stress type (maximum

- SR-P; or alternating - SR-a)..

Stress Location Location (in.) node Stress Intensity (psi) Stress Ratio Dom.

Ratio x y z Pm Pm+Pb Salt SRP SRa Freq. (Hz)

SRP 1. Outer portion of inner hood (top near 109 27.6 95.3 44886 6764 9587 1310 2.5 9.44 46.7 closure plate)

SRa 1. Middle Hood 30.2 68.9 35.2 37937 1242 5583 5297 4.54 2.33 49.0

" 2. Middle Hood 28.4 67.3 52.2 37238 1430 5502 5194 4.61 2.38 49.0

" 3. Middle Hood 24.2 64.9 69 37916 1330 5486 5157 4.62 2.40 49.0

" 4. Middle Hood 29.6 69.7 20.3 37971 910 5082 4804 4.99 2.57 49.0

" 5. Middle Hood 27.6 62 84.6 37967 983 5001 4678 5.07 2.64 49.0

" 6. Middle Hood 34.2 64.9 68.8 37263 1135 4975 4675 5.10 2.64 49.0

" 7. Middle Hood 18.8 68.9 35.9 37299 1294 4767 4489 5.32 2.75 48.2

" 8. Inner Hood 30.4 33.5 68.2 42011 1127 4768 4472 5.32 2.76 47.7 Table 3b. Limiting peak stress ratios, SR-P, on welds at MUR with no frequency shift.

Location Location (in.) Stress Intensity (psi) Stress Ratio Dom.

x y z node Pm Pm+Pb Salt SRP SRa Freq. (Hz)

1. Skirt/Cap Strip/Skirt Ext 118.8 0.6 2 88325 2579 10505 1671 1.33 4.11 46.8
2. Closure Plate/Hood 108.4 27.9 94.9 85409 5961 8753 2263 1.56 3.03 47.7
3. Backing Bar/Hood Support/Mid Cover Plate 0 38.4 7.5 79684 5068 5126 2779 1.83 2.47 48.7
4. Inner Side Panel/Vane Bank/Mid Cover Plate 118.8 14.4 7.5 85994 4593 6335 868 2.02 7.92 46.9
5. Hood Support/Mid Cover Plate/Backing Bar 59.5 38.4 7.5 86958 4523 4722 2512 2.05 2.73 47.7
6. Backing Bar/Hood 29.1 69.9 8.5 87919 732 6673 6243 2.09 1.10 49.0
7. Drain Channel/Bottom Skirt 118.2 12 94.2 90843 1761 6666 4001 2.09 1.72 31.7 15

This document does not contain Continuum Dynamics, Inc. Proprietary Information Table 3c. Limiting alternating stress ratios, SR-a, on welds at MUR with no frequency shift.

Location Location (in.) Stress Intensity (psi) Stress Ratio Dom.

x y z node Pm Pm+Pb Salt SRP SRa Freq. (Hz)

1. Backing Bar/Middle Hood 29.1 69.9 8.5 87919 732 6673 6243 2.09 1.10 49.0
2. Backing Bar/Inner Hood 29.5 38.4 8.5 85224 681 5532 5200 2.52 1.32 47.7
3. Backing Bar/Middle Hood 16.5 69.9 8.5 87922 1106 5222 4887 2.67 1.41 49.0
4. Drain Channel/Bottom of Skirt 73.8 93.1 94.2 90834 2216 6502 4226 2.14 1.63 47.3
5. Backing Bar/Inner Hood 42.3 38.4 8.5 85227 1323 4560 4217 3.06 1.63 47.7
6. Hood Support/Inner Hood(a) 0 36.1 49.6 88022 1788 4275 4054 3.26 1.69 47.7
7. Hood Support/Middle Hood(a) 0 68.7 38.4 87904 1558 4243 4031 3.29 1.70 45.3
8. Drain Channel/Bottom of Skirt 118.2 12 94.2 90843 1761 6666 4001 2.09 1.72 31.7
9. Backing Bar/Middle Hood 42.1 69.9 8.5 87826 1244 4210 3979 3.31 1.73 49.0
10. Hood Support/Middle Hood (a) 0 67.1 53.3 87900 1741 4272 3921 3.26 1.75 45.0
11. Backing Bar/Inner Hood 17.2 38.4 8.5 88057 1306 4176 3851 3.34 1.78 47.7
12. Backing Bar/Inner Hood 81.5 38.4 8.5 85461 582 4051 3707 3.44 1.85 47.7
13. Hood Support/Inner Hood(a) 0 37.2 38.4 80716 1589 4028 3707 3.46 1.85 41.5
14. Hood Support/Middle Hood(a) 0 65 68.1 87896 1422 4171 3702 3.34 1.86 45.3
15. Hood Support/Middle Hood(a) 0 34.7 60.8 80662 1588 3708 3440 3.76 2.00 41.5 Note: (a) Full penetration weld so that weld factor, WF=1.4.

16

This document does not contain Continuum Dynamics, Inc. Proprietary Information Table 4a. Limiting non-weld locations at MUR with frequency sh ifts. Stress ratios are grouped a ccording to stress type (maximum -

SR-P; or alternating - SR-a). Locations are depicted in Figure 3a-b.

Stress Location Location (in.) node Stress Intensity (psi) Stress Ratio % Freq. Dom.

Ratio x y z Pm Pm+Pb Salt SRP SRa Shift Freq. (Hz)

SRP 1. Outer portion of inner hood (top near 109 27.6 95.3 44886 6842 9587 1377 2.47 8.98 10 48.7 closure plate)

" 2. Bottom of inner hood 110.8 38.4 10.2 41448 4875 4906 2882 3.47 4.29 10 48.2

" 3. Midheight of inner hood 83.4 35.9 50.9 40188 3727 6843 6444 3.70 1.92 10 48.7 SRa 1. Inner hood 83.4 35.9 50.9 40188 3727 6843 6444 3.70 1.92 10 48.7

" 2. Middle Hood 25.6 68.9 35.1 37926 1612 5908 5598 4.29 2.21 2.5 47.5

" 3. Middle Hood 28.4 67.3 52.2 37238 1735 5853 5532 4.33 2.24 2.5 47.5

" 4. Middle Hood 24.2 64.9 69 37916 1516 5936 5498 4.27 2.25 2.5 47.5

" 5. Inner Hood 84 37.2 37.7 40185 3291 5550 5262 4.57 2.35 10 48.7

" 6. Inner Hood 30.4 33.5 68.2 42011 1723 5542 5222 4.57 2.37 2.5 48.6

" 7. Inner Hood 93.6 36 50.8 40554 3013 5436 5166 4.66 2.39 10 48.7

" 8. Inner Hood 28.6 37.4 36.1 41834 1796 5456 5159 4.65 2.40 2.5 48.6

" 9. Inner Hood 73.2 36 50.4 40518 2845 5387 5063 4.71 2.44 10 48.7 17

This document does not contain Continuum Dynamics, Inc. Proprietary Information Table 4b. Limiting peak stress ratios, SR-P, on welds at MUR with frequency shifts. Locations are depicted in Figure 3c-e.

Location Location (in.) Stress Intensity (psi) Stress Ratio % Freq. Dom.

x y z node Pm Pm+Pb Salt SRP SRa Shift Freq. (Hz)

1. Skirt/Cap Strip/Skirt Ext 118.8 0.6 2 88325 2951 11048 1996 1.26 3.44 2.5 22.4
2. Closure Plate/Inner Hood 108.4 27.9 94.9 85409 6161 9041 2474 1.51 2.78 2.5 46.8
3. Bottom Skirt/Drain Channel 73.8 93.1 94.2 93833 2319 8247 5988 1.69 1.15 10 28.4
4. Inner Hood Support/Mid Cover Plate/Backing Bar 0 38.4 7.5 86960 5368 5418 3169 1.73 2.17 10 48.6
5. Inner Hood Support/Vane Bank/Mid Cover Plate 0 22.9 7.5 93159 5264 5299 3949 1.77 1.74 10 36.8
6. Drain Pipe/Skirt 88.2 79.6 20.5 91083 2718 7665 2284 1.82 3.01 10 48.7
7. KT1444/Inner Hood 109.8 38.4 9.5 92106 5027 5028 2549 1.85 2.69 10 48.6
8. Bottom Skirt/Drain Channel 118.2 12 94.2 93758 2266 7416 4925 1.88 1.39 5 47.3
9. Side Vane Bank/Mid Cover Plate 118.8 14.4 7.5 86577 4888 6763 1198 1.90 5.74 5 46.3
10. Middle Side Panel/Top Cover/Top Perf. Plate/ 108.4 45.9 95.9 85891 4706 5397 1526 1.98 4.50 10 36.8 Closure Plate 18

This document does not contain Continuum Dynamics, Inc. Proprietary Information Table 4c. Limiting 21 alternating stress ratios, SR-a, on welds at MUR with frequency shifts. Locations are depicted in Figure 3f-h.

Location Location (in.) Stress Intensity (psi) Stress Ratio % Freq. Dom.

x y z node Pm Pm+Pb Salt SRP SRa Shift Freq. (Hz)

1. Backing Bar/Middle Hood 29.1 69.9 8.5 87919 923 6983 6566 2.00 1.05 2.5 47.7
2. Backing Bar/Inner Hood 30 38.4 8.5 88060 1258 6630 6194 2.10 1.11 2.5 48.6
3. Hood Support/Inner Hood(a) 0 36.1 49.6 80664 2793 6558 6148 2.13 1.12 10 36.8
4. Drain Channel/Bottom of Skirt 73.8 93.1 94.2 93833 2319 8247 5988 1.69 1.15 10 28.4
5. Hood Support/Inner Hood(a) 0 37.2 38.4 88025 2613 6510 5978 2.14 1.15 10 36.8
6. Hood Support/Inner Hood(a) 0 34.7 60.8 88019 2545 6161 5744 2.26 1.20 10 36.8
7. Drain Channel/Bottom of Skirt 118.2 12 94.2 82775 2636 6037 5677 2.31 1.21 10 47.7
8. Backing Bar/Inner Hood 81.9 38.4 8.5 85261 1367 5470 5131 2.55 1.34 10 48.7
9. Backing Bar/Middle Hood 16.5 69.9 8.5 87922 1408 5401 4997 2.58 1.37 2.5 47.7
10. Hood Support/Middle Hood(a) 0 68.3 42.2 87903 2143 5420 4917 2.57 1.40 5 47.7
11. Hood Support/Inner Hood(a) 59.5 36.1 49.6 88043 2131 5250 4909 2.66 1.40 10 36.8
12. Hood Support/Middle Hood(a) 0 67.1 53.3 87900 2342 5115 4705 2.73 1.46 7.5 41.8
13. Backing Bar/Inner Hood 17.2 38.4 8.5 88057 1584 4968 4609 2.81 1.49 2.5 48.6
14. Backing Bar/Inner Hood 42.7 38.4 8.5 88063 1891 4952 4605 2.82 1.49 2.5 48.6
15. Hood Support/Inner Hood(a) 59.5 37.2 38.4 88046 2061 4906 4573 2.84 1.50 10 36.8
16. Hood Support/Middle Hood(a) 0 65.6 64.4 87897 2017 4893 4534 2.85 1.51 5 47.7
17. Hood Support/Inner Hood(a) 0 37.9 27.2 88028 2022 4905 4515 2.84 1.52 10 36.8
18. Hood Support/Inner Hood(a) 0 32.9 71.9 88016 1927 4690 4429 2.97 1.55 10 36.8
19. Hood Support/Inner Hood(a) 59.5 34.7 60.8 88040 2006 4690 4319 2.97 1.59 10 36.8
20. Backing Bar/Middle Hood 42.1 69.9 8.5 87826 1637 4384 4152 3.18 1.65 2.5 47.7
21. Backing Bar/Inner Hood 94.8 38.4 8.5 85455 2734 4351 4012 3.20 1.71 10 48.6 Note: (a) Full penetration weld so that weld factor, WF=1.4.

19

This document does not contain Continuum Dynamics, Inc. Proprietary Information Table 4d. Re maining nodes on w elds with al ternating stress ratios, S R-a, on welds belo w 2.0 at MUR conditions with frequency shifts. Locations are depicted in Figure 3f-h.

Location Location (in.) Stress Intensity (psi) Stress Ratio % Freq. Dom.

x y z node Pm Pm+Pb Salt SRP SRa Shift Freq. (Hz)

22. Hood Support/Vane Bank/Mid Cover Plate 0 22.9 7.5 93159 5264 5299 3949 1.77 1.74 10 36.8
23. Outlet Plenum/Inner Hood 108.4 35.9 51.5 85304 1737 4285 3938 3.25 1.74 10 48.7
24. Hood Support/Middle Hood (a) 0 69.2 31 87906 1718 4240 3855 3.29 1.78 5 47.7
25. Backing Bar/Inner Hood 68.6 38.4 8.5 85256 3216 4014 3786 2.89 1.81 10 48.7
26. Hood Support/Inner Hood(a) 59.5 37.9 27.2 88049 1827 4005 3776 3.48 1.82 10 36.8
27. Hood Support/Middle Hood(a) 54.5 67.1 53.3 87806 1211 3919 3548 3.56 1.94 10 46.8
28. Hood Support/Middle Hood(a) 0 69.7 19.7 87909 1119 3653 3460 3.82 1.99 2.5 47.7 Note: (a) Full penetration weld so that weld factor, WF=1.4.

20

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 3a. Locations of m inimum stress ratios, SR-P 4, associated with m aximum stress intensities at non-welds for MUR with frequenc y shifts. The recorded stress ratio is the minimum value taken over all frequency shifts. The number refer to the enumerated location for SR-P values at non-welds in Table 4a. This view shows location 1 and 3.

21

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 3b. Locations of m inimum stress ratios, SR-P 4, associated with m aximum stress intensities at non-welds for MUR operation with frequency shifts. The recorded stress ratio is the minimum value taken over all f requency shifts. Numbers refer to the enum erated locations for SR-a values at non-welds in Table 4a. This view shows location 2.

22

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 3c. Locations of m inimum alternating stress ratios, SR-a 3, at non-welds for MUR operation with frequency shifts. The recorded st ress ratio at a node is the m inimum value taken over all frequency shifts. Numbers refer to the enumerated locations for SR-P values at welds in in Table 4a. All locations 1-9 are shown.

23

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 3d. Locations of m inimum stress ratios, SR-P 4, associated with m aximum stress intensities at welds for MUR with frequency shifts. The recorded stress ratio at a node is the minimum value taken over all frequency shifts. Numbers refer to the en umerated locations for SR-P values at welds in in Table 4b. This view shows locations 1-3, 7, 9 and 10.

24

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 3e. Locations of m inimum stress ratios, SR-P 4, associated with m aximum stress intensities at welds for MUR with frequency shifts. The recorded stress ratio at a node is the minimum value taken over all frequency shifts. Numbers refer to the en umerated locations for SR-P values at welds in in Table 4b. This view shows locations 1, and 3-8.

25

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 3f. Locations of m inimum alternating stress ratios, SR-a4, at welds f or MUR with frequency shifts. The recorded stress ratio at a node is th e minimum value taken over all frequency shifts. Numbers refer to the enum erated locations for SR-a values at we lds in Table 4c-d. Locations 1-20 and 22-28 are shown 26

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 3g. **Locations of mini mum alternating stress ratios, SR-a 4, at welds f or MUR with frequency shifts. The recorded stress ratio at a node is th e minimum value taken over all frequency shifts. Numbers refer to the enum erated locations for SR-a values at we lds in Table 4c-d. Second view showing locations 1, 2, 4, 5, 9, 10, 13, 14, 17, 20-22, 24 and 28.

27

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 3h. Locations of minimum alternating stress ratios, SR-a4, at welds for with frequency shifts. The recorded stress ratio at a node is th e minimum value taken over all frequency shifts.

Numbers refer to the en umerated locations for SR-a values at welds in Table 4c-d. Third view showing location 23.

28

This document does not contain Continuum Dynamics, Inc. Proprietary Information 2.3 Frequency Content and Sensitivity to Frequency Shift of the Stress Signals The spectral content in the stress respons e is exam ined by presenting the P SD and accumulative PSDs of selected no des and stress com ponents. Th e accumulative PSDs are computed directly from the Fourier coefficients as where is th e complex stress h armonic at frequ ency, k. Accum ulative PSD plots are useful for determ ining the frequency com ponents and frequency ranges that m ake the largest contributions to th e fluctuating stress. Un like PSD plots, no bi nning or smoothing of frequency components is needed to obtain smooth curves. Steep step-like rises in () indicate the presence of a strong com ponent at a discre te frequency whereas gr adual increases in the curve imply significant content over a broader frequency range. From Parsivals theorem, equality between (N) (where N is the total number of frequency components) and the RMS of the stress signal in the time domain is established.

The accumulative PSD and PSDs are exam ined at five nod es each one representative of a weld configuration (a)-(e) as described in Section 5.2. These nodes are listed in Table 5.

Table 5. List of nodes selected for plotting stress PSDs in Figure 4.

Location Entry in Node SRa. Dom. Freq. PSDs Table 4c, d Backing Bar/Middle Hood 1 87919 1.05 47.7 Figure 4a Hood Support/Inner Hood 3 80664 1.12 36.8 Figure 4b Bottom Skirt/Drain Channel 4 93833 1.15 28.4 Figure 4c Hood Support/Vane 22 93159 1.74 36.8 Figure 4d Bank/Mid Cover Plate Closure Plate/Inner Hood 23 85304 1.74 48.7 Figure 4e In each case, since there are six stress com ponents and up to three different section lo cations for shells (the top, mid and botto m surfaces), there are a total of 18 stress h istories per component. Moreover, at junctions there are at least two components that m eet at the junction.

The particular stress component that is plotted is chosen as follows. Fi rst, the component and section location (top/mid/bottom) is taken as the one that has the hi ghest alternating stress. This narrows the selection to six components. Of these, the component having the highest Root Mean Square (RMS) is selected.

The accumulative PSD and PSD curves are p resented in Figure 4. The stress response at the limiting node (87919) is characterize d by a single distinct peak about 47.7 Hz. This peak does not shift significantly with frequency shift, which is indicative of a structural mode being excited by a relatively broad acoustic peak. For the second location (80664) two peaks are present at 29

This document does not contain Continuum Dynamics, Inc. Proprietary Information approximately 37 Hz and 48 Hz; frequency shif ting amplifies the f ormer peak to becom e dominant. The third location has a m uch richer spectrum reflecting the fact th at the skirt contains many modes in the 0-200 Hz range. The fourth location (node 85304) is similar to the first location in that it contain s a s ingle dominant peak, here at app roximately 52 Hz which corresponds to a structural m ode that is excited when the 48.7 Hz peak in the lo ad is shifted upward by +10%. Finally, the fi fth node 93159 exhibits two peaks, again involving prim arily the signal peaks at 36.8 Hz and 47.7-48.7 Hz.

From Table 4c-d it is evident that these are two peak frequencies dominate most of the stress response. The prevalence of these frequencies can also be visualized by plotting the dom inant frequency over the dryer surface. Thus, for each finite element node the frequency associated with the largest stress harmonic (at any frequency shift) is recorded . As in Table 4 and Table 5, the pre-shift frequency is used. A contour m ap of this dominant frequency is shown in Figure 5 and provides a qualitative view of which dryer co mponents appear most responsive to particular frequencies. Low frequency responses in the range 30-50 Hz dom inate the inner and m iddle hoods, vane bank side plates, hood supports, and a large portion of the skirt. Over the 50-150 Hz range only the outer hoods exhi bit a significant response, though these stresses are m uch lower than those at frequencies below 50 Hz.

Overall, the frequency responses and dominant frequency distributions are very similar to the ones in [3], which is exp ected since the applied signals are essentially identical (the scaling used to infer MUR f rom CLTP does not alte r the f requency content other than the velocity square scaling of the am plitudes) and the PPD influence is limited to the v icinity of the perf orated plates.

30

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 4a. Accumulative PSD and PSD curves of the zz stress response at node 87919 at MUR operation.

31

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 4b. Accumulative PSD and PSD curves of the xx stress response at node 80664 at MUR operation 32

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 4c. Accumulative PSD and PSD curves of the xx stress response at node 93833 at MUR operation.

33

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 4d. Accumulative PSD and PSD curves of the yy stress response at node 93159 at MUR operation.

34

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 4e. Accumulative PSD and PSD curves of the xx stress response at node 85304 at MUR operation.

35

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 5a. Contour m ap showing the dominant frequencies (i.e., the frequency with the largest stress harmonic). This shows locations with dominant frequencies in the range 30-50 Hz.

36

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 5b. Contour m ap showing the dom inant frequencies (i.e., the fre quency with the largest stress harmonic). This second view shows locat ions with dominant frequencies in the range 30-50 Hz exposing more of the inner and middle hood structures.

37

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 5c. Contour m ap showing the dominant frequencies (i.e., the frequency with the largest stress harmonic). This plot shows locations with dominant frequencies in the range 50-150 Hz.

38

This document does not contain Continuum Dynamics, Inc. Proprietary Information

3. Comparison of Stresses With and Without PPD In order to assess the relative significance of PPD upon the steam dryer response, the results obtained here at MUR conditions with PPD are compared against those acquired without PPD.

The latter results are obtained using the real tim e stress e valuation capability in the harm onic stress analysis software which allo ws the s tresses to b e calculated at selected locations on the dryer. Here the limiting locations identified at MUR with PPD are rep rocessed using the sam e MUR signals, but the FEA model without VIL (i.e., as used in CDI Report 15-06, [3]).

Table 6 compares the stress ratios obtained with and without PPD at MUR operation. The limiting location experiences a 1.2% stress reduction which increases the stress ratio from 1.04 to 1.05. Stress reductions in the vicinity of perf orated plates are genera lly in the 1-2% range; further away at the drain channels the changes are smaller as expected.

Overall, the reductions in stre ss at the lim iting locations are smaller than des ired. The influence of PPD on st ress near the perforated plates depends on several factors including :

relative thicknesses of the affected parts, mode shapes, frequency (higher frequency m odes are less affected by PPD), and how well an acoustic m ode couples into the structure. Modes that involve significant perforated plate m otion generally experience th e strongest reduction, particularly if the modal mass contribution from the perforated pl ates is a significant fraction of the total modal mass for that mode. Estimating the relative contribution of PPD to a particular node near the perforated plat es is generally not possible a priori other than: (i) the expectation that nodes far away from the perforated plates s hould experience a negligib le change in stress; and (ii) past experience with PPD dam ping for nodes near the perforated plates indicates stress reductions in the approxim ate range of 0 to 10%. Outlie rs with larg er stress reductions are possible as are stress increases in some cases, typically ones where the st resses are displacement rather than force driven.

Figure 6 shows the stress changes due to PPD for all nodes on the dr yer with SR-a<5 (at MUR) excluding the p erforated plates themselves. This plot concurs w ith prior experience i n using PPD. Up to 23% stress reduction is obser ved for isolated locations; however, for SR-a<3 the largest reduction is 3.7%. Som e stress in creases are observed re flecting the expected behavior when a stress is displa cement driven, meaning that the stress results mainly from the response induced by more distant loads than from local loads (e.g., the global dryer response due to loads on the outer hoods). The distribution of the stress change over the dryer is depicted in Figure 7 which shows that, as expected, the m ain stress reductions occur on the perforated plates and attached structures. The view from underneath the dryer (Figure 7b) reveals that the bottoms of the hood supports do experience reductions of appr oximately 3% in some cases, but not in the limiting locations. For exam ple, the m iddle hood/cover plate/backing bar junction (entry 10, node 87903) experiences a stress reduction of 2.6% . However, SR-a= 1.40 so this reduction is not at the location where it is most needed.

In a summary sense, the overall PPD effect is within expectations, albeit somewhat weaker than experienced at some other plants. While the stresses at the limiting locations are reduced, these locations continue to be limiting.

39

This document does not contain Continuum Dynamics, Inc. Proprietary Information Table 6. Comparison of stress ratios computed at MUR with and without PPD Location node No PPD With PPD RPPD (1)

SRP SRa SRP SRa  %

1. Backing Bar/Middle Hood 87919 1.98 1.04 2.00 1.05 1.2
2. Backing Bar/Inner Hood 88060 2.09 1.10 2.10 1.11 0.7
3. Hood Support/Inner Hood 80664 2.12 1.11 2.13 1.12 0.5
4. Drain Channel/ Bottom of Skirt 93833 1.69 1.15 1.69 1.15 0.1
5. Hood Support/Inner Hood 88025 2.14 1.14 2.14 1.15 0.8
6. Hood Support/Inner Hood 88019 2.24 1.19 2.26 1.20 0.9
7. Drain Channel/Bottom of Skirt 82775 2.32 1.21 2.31 1.21 0.3
8. Backing Bar/Inner Hood 85261 2.55 1.34 2.55 1.34 0.3
9. Backing Bar/Middle Hood 87922 2.55 1.36 2.58 1.37 0.4
10. Hood Support/Middle Hood 87903 2.51 1.36 2.57 1.40 2.6
11. Hood Support/Inner Hood 88043 2.65 1.40 2.66 1.40 0.2
12. Hood Support/Middle Hood 87900 2.69 1.44 2.73 1.46 1.5
13. Backing Bar/Inner Hood 88057 2.79 1.48 2.81 1.49 0.6
14. Backing Bar/Inner Hood 88063 2.79 1.48 2.82 1.49 0.8
15. Hood Support/Inner Hood 88046 2.83 1.50 2.84 1.50 0.2
16. Hood Support/Middle Hood 87897 2.78 1.48 2.85 1.51 2.0
17. Hood Support/Inner Hood 88028 2.84 1.52 2.84 1.52 0.1
18. Hood Support/Inner Hood 88016 2.94 1.53 2.97 1.55 1.0
19. Hood Support/Inner Hood 88040 2.96 1.58 2.97 1.59 0.3
20. Backing Bar/Middle Hood 87826 3.17 1.65 3.18 1.65 0.0
21. Backing Bar/Inner Hood 85455 3.20 1.71 3.20 1.71 0.2
22. Hood Support/Vane Bank/Mid 93159 1.77 1.74 1.77 1.74 0.1 Cover Plate
23. Outlet Plenum/Inner Hood 85304 3.24 1.74 3.25 1.74 0.1
24. Middle Hood Support/Hood 87906 3.21 1.74 3.29 1.78 2.2
25. Backing Bar/Inner Hood 85256 2.88 1.81 2.89 1.81 0.1
26. Hood Support/Inner Hood 88049 3.48 1.82 3.48 1.82 0.2
27. Hood Support/Middle Hood 87806 3.49 1.90 3.56 1.94 2.1
28. Hood Support/Middle Hood 87909 3.80 1.97 3.82 1.99 0.8
1. RPPD is the change in stress achieved with PPD.

40

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 6. Stress reduction due to PPD at all points with SR-a <5. Perforated plate s themselves are excluded from this list.

41

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 7a. Distribution of stress reduction on HC1 dryer due to PPD.

42

This document does not contain Continuum Dynamics, Inc. Proprietary Information Figure 7b. Distribution of st ress reduction on HC1 dryer due to P PD (second view from underneath the dryer).

43

This document does not contain Continuum Dynamics, Inc. Proprietary Information

4. Conclusions A harmonic steam dryer stress analysis with perforated plate damping accounted for has been used to calculate high stress locations and stress ratios fo r the HC1 steam dryer at MU R conditions using plant m easurement data. The loads obtained in a separate acoustic circuit model [9], including end-to-end bias and uncertain ty [4, 9], were applied to a finite elem ent model of t he steam dryer consisting m ainly of the ANSYS Shell 63 elem ents and brick continuum elements. The resulting stress hist ories were analyzed to obtain alternating and maximum stresses at all nodes for com parison against allowable levels . These results are tabulated in Table 4 of this re port and compared against the corresponding predictions without PPD in Table 6. The minimum alternating stress ratio (SR-a) at any frequency shift is 1.05. The most limiting maximum stress intensity stress ratio (SR-P) is 1.25. These results account for all end-to-end biases and uncertainties and meet the ASME code requirements.

On the basis of these MUR plant loads, the dyna mic analysis of the steam dryer shows that the combined acoustic, hydrodynamic, and gravit y loads produce the following m inimum stress ratios:

Frequency Shift Minimum Stress Ratio Max. Stress, Alternating Stress, SR-P SR-a

-10% 1.35 1.33

-7.5% 1.34 1.52

-5% 1.35 1.40

-2.5% 1.26 1.11 0% (nominal) 1.33 1.10

+2.5% 1.31 1.05

+5% 1.31 1.22

+7.5% 1.28 1.17

+10% 1.27 1.12 All shifts 1.26 - 1.35 1.05 - 1.52 The limiting stress locations with SR-a<2 are s imilar to those obtained without PPD. While stress reductions of up to 23% are observed at some significant stress locations (SR-a<5) near the perforated plates and up to 2.6 % for locations with SR-a<1.40, the limiting stress location only sees a stress reduction of 1.2% or a n alternating stress ratio increase from SR-a= 1.04 without PPD to SR-a=1.05 with PPD. He nce this location on the middle hood/backing bar weld remains the limiting location.

44

This document does not contain Continuum Dynamics, Inc. Proprietary Information

5. References
1. Continuum Dynamics, Inc. (2016) Basis for Modeling Vibration-Induced Loading in Steam Dryers. C.D.I. Technical Note No.16-16P (Proprietary), Rev. 0, Oct.
2. Continuum Dynamics, Inc. (2016) Stress Evaluation of Hope Creek Unit 1 Steam Dryer at CLTP and MUR Conditions Using 42.5% VIL. C.D.I. Report No.16-09P (Proprietary), Rev. 0, Oct.
3. Continuum Dynamics, Inc. (2015) Stress Re-Evaluation of Hope Creek Unit 1 Steam Dryer at 115% CLTP. C.D.I. Report No.15-06P (Proprietary), Rev. 0, Oct.
4. Continuum Dynamics, Inc. (2015) Design Record File DRF-PSEG-352.
5. Continuum Dynamics, Inc. (2007) Finite Element Modeling Bias and Uncertainty Estimates Derived From the Hope Creek Unit 2 Dryer Shaker Test, Revision 0. CDI Report No.07-27P.
6. Continuum Dynamics, Inc. (2014) Stress Re-Evaluation of Nine Mile Point Unit 2 Steam Dryer at 115% CLTP. C.D.I. Report No.14-08P (Proprietary), July.
7. Continuum Dynamics, Inc. (2009) Stress Assessment of Browns Ferry Nuclear Unit 1 Steam Dryer to 120% OLTP Power Level, Rev. 0. C.D.I. Report No.09-25P (Proprietary), August.
8. Continuum Dynamics, Inc. (2007) Dynamics of BWR Steam Dryer Components. C.D.I.

Report No.07-11P.

9. Continuum Dynamics, Inc. (2007) Methodology to Predict Full Scale Steam Dryer Loads from In-Plant Measurements, with the Inclusion of a Low Frequency Hydrodynamic Contribution. C.D.I. Report No.07-09P (Proprietary).
10. ASME (2007) Boiler and Pressure Vessel Code,Section III, Subsection NG.
11. de Santo, D.F., Added Mass and Hydrodynamic Damping of Perforated Plates Vibrating In Water. Journal of Pressure Vessel Technology, 1981. 103: p. 175-182.
12. Idel'chik, I E. and E. Fried, Flow Resistance, a Design Guide for Engineers. 1989, Washington D.C.: Taylor & Francis. pg. 260.

45 LAR H17-03 LR-N17-0186 CDI Affidavit supporting the withholding of information in Enclosure 3 from public disclosure

bJlt" Continuum Dynamics, Inc.

(609) 538-0444 (609) 538-0464 fax 34 Lexington Avenue Ewing, NJ 08618-2302 AFFIDAVIT RE: CDI Teclmical Note No.16-23P "Stress Evaluation of Hope Creek Unit 1 Steam Dryer at MUR Conditions Using Perforated Plate Damping," Revision 0 I, Alan J. Bilanin, being duly sworn, depose and state as follows:

1. I hold the position of President and Senior Associate of Continuum Dynamics, Inc. (hereinafter refened to as CDI), and I am authorized to make the request for withholding from Public Record the Information contained in the document described in Paragraph 2. This Affidavit is submitted to the Nuclear Regulato1y Commission (NRC) pursuant to 10 CFR 2.390(a)(4) based on the fact that the attached information consists of trade secret(s) of CDI and that the NRC will receive the Information from CDI under privilege and in confidence.
2. The Information sought to be withheld, as transmitted to PSEG Nuclear LLC as attachment to CDI Letter No. 17077 dated 13 December 2017, CDI Technical Note No.16-23P "Stress Evaluation of Hope Creek Unit 1 Steam Dryer at MUR Conditions Using Perforated Plate Damping," Revision 0. The proprietary information is identified by its enclosure within pairs of double square bra ckets ("(( ))"). In each case, the supe rscript not ation (J) refers to Paragraph 3 of this affidavit that provides the basis for the proprietary detem1ination.
3. The Information summarizes:

(a) a process or method, including supporting data and analysis, where prevention of its use by CDI's competitors without license from CDI constitutes a competitive advantage over other companies; (b) Information which, if used by a competitor, would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing of a similar product; (c) Infonnation which discloses patentable subject matter for which it may be desirable to obtain patent protection.

The information sought to be withheld is considered to be proprietary for the reasons set forth in paragraphs 3(a), 3(b) and 3(c) above.

4. The Information has been held in confidence by CDI, its owner. The Information has consistently been held in confidence by CDI and no public disclosure has been made and it is not available to the public. All disclosures to third parties, which have been limited, have been made pm*suant to the terms and conditions contained in CDI's Nondisclosme Secrecy Agreement which must be fully executed prior to disclosure.
5. The Information is a type customarily held in c onfidence by CDI and.there is a rational basis therefore . The I11formation is a type, which CDI considers trade secret and is held in confidence by CDI be cause it constitutes a source of competitive advantage in the competition and performance of such work in the industry. Public disclosure of the Information is likely to cause substantial hann to CDI's competitive po sitio n and foreclose or reduce the availability of profit-making oppottunities.

I de clare under penalty of perjury that the foregoing affidavit and the matters stated therein are true and correct to be the best of my knowledge, information and belief.

Executed on this 13th day of December 2017.

Alan ]; Hilanin BJ Continuum Dynam Subscribed and sworn before me this day: 13 December 2017

  • r--c]u_ Aj v/14?t..t. t-S enP. B U¢ierst e , NotaryPublic EILEEN P BURMEISTER 10t22011690

. NOTARYPUS LI Ny lfJira 2022

Retrieved from "https://kanterella.com/w/index.php?title=LR-N17-0186,_Response_to_Request_for_Additional_Information_Regarding_License_Amendment_Request_for_Measurement_Uncertainty_Recapture_Power_Uprate&oldid=2621551"