ML092460495

CDI Report No. 09-23NP, Rev. 0, Acoustic and Low Frequency Hydrodynamic Loads at CLTP Power Level to 120% OLTP Power Level on Browns Ferry Nuclear Unit 1 Steam Dryer to 250 Hz, Enclosure 6

ML092460495
Person / Time
Site:	Browns Ferry
Issue date:	08/31/2009
From:	Teske M Continuum Dynamics
To:	Office of Nuclear Reactor Regulation, Tennessee Valley Authority
References
00077408, TAC MD5262, TS-431 CDI Report No. 09-23NP, Rev 0
Download: ML092460495 (30)

Text

ENCLOSURE6 TENNESSEE VALLEY AUTHORITY BROWNS FERRY NUCLEAR PLANT (BFN)

UNIT 1 TECHNICAL SPECIFICATIONS (TS) CHANGE TS-431 EXTENDED POWER UPRATE (EPU)

CDI REPORT NO. 09-23NP, "ACOUSTIC AND LOW FREQUENCY HYDRODYNAMIC LOADS AT CLTP POWER LEVEL TO 120% OLTP POWER LEVEL ON BROWNS FERRY NUCLEAR UNIT I STEAM DRYER TO 250 HZ," REVISION 0 (NON-PROPRIETARY VERSION)

Attached is the non-proprietary version of CDI Report No. 09-23NP, "Acoustic and Low Frequency Hydrodynamic Loads at CLTP Power Level to 120% OLTP Power Level on Browns Ferry Nuclear Unit 1 Steam Dryer to 250 Hz."

This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information C.D.I. Report No. 09-23NP Acoustic and Low Frequency Hydrodynamic Loads at CLTP Power Level to 120%

OLTP Power Level on Browns Ferry Nuclear Unit 1 Steam Dryer to 250 Hz Revision 0 Prepared by Continuum Dynamics, Inc.

34 Lexington Avenue Ewing, NJ 08618 Prepared under Purchase Order No. 00077408 for TVA / Browns Ferry Nuclear Plant Nuclear Plant Road, P. 0. Box 2000 PAB-2M Decatur, AL 35609 Approved by Alan J. Bilanin Prepared by Milton E. Teske August 2009

This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information Executive Summary Measured strain gage time-history data in the four main steam lines at Browns Ferry Nuclear Unit 1 (BFN1) were processed by a dynamic model of the steam delivery system to predict loads on the full-scale steam dryer. These measured data were first converted to pressures, then positioned on the four main steam lines and used to extract acoustic sources in the system. A validated acoustic circuit methodology was used to predict the fluctuating pressures anticipated across components of the steam dryer in the reactor vessel. The acoustic circuit methodology included a low frequency hydrodynamic contribution, in addition to an acoustic contribution at all frequencies. This pressure loading was then provided for structural analysis to assess the structural adequacy of the steam dryer in BFN 1.

This effort provides BFN I with a dryer dynamic load definition that comes directly from measured BFN1 full-scale data and the application of a validated acoustic circuit methodology, at a power level where data were acquired.

This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information Table of Contents Section Page Executive Sum mary .................................................................. i T able of Contents ..................................................................... ii

1. Introdu ction ............................................................................ 1

2. Modeling Considerations .......................................................... 2 2.1 H elmholtz Analysis ........................................................... 2 2.2 Acoustic Circuit Analysis .................................................... 3 2.3 Low Frequency Contribution ................................................ 4

3. Input Pressure D ata .......................................... ................. 5 4 . R esu lts ................................................................................. 13

5. Uncertainty A nalysis ............................................................... 20

6. Bump-Up Factors for 120% OLTP Power ....................................... 22

7. Conclusions ........................................................................... 24

8. R eferences ............................................................................. 25 ii

This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information

1. Introduction In Spring 2005 Exelon installed new stream dryers into Quad Cities Unit 2 (QC2) and Quad Cities Unit 1. This replacement design, developed by General Electric, sought to improve dryer performance and overcome structural inadequacies identified on the original dryers, which had been in place for the last 30 years. As a means for confirming the adequacy of the steam dryer, the QC2 replacement dryer was instrumented with pressure sensors at 27 locations. These pressures formed the set of data used to validate the predictions of an acoustic circuit methodology under development by Continuum Dynamics, Inc. (C.D.I.) for several years [1].

One of the results of this benchmark exercise [2] confirmed the predictive ability of the acoustic circuit methodology for pressure loading across the dryer, with the inclusion of a low frequency hydrodynamic load. This methodology, validated against the Exelon full-scale data and identified as the Modified Bounding Pressure model, is used in the effort discussed herein.

This report applies this validated methodology to the Browns Ferry Nuclear Unit 1 (BFN1) steam dryer and main steam line geometry. Strain gage data obtained from the four main steam lines were used to predict pressure levels on the BFN1 full-scale dryer at Current Licensed Thermal Power (CLTP). In addition, bump-up factors, obtained from subscale test data

[3], were used to modify the CLTP strain gage data to predict the pressure levels on the BFNI full-scale dryer at 120% of Original Licensed Thermal Power (OLTP).

This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information

2. Modeling Considerations The acoustic circuit analysis of the BFN1 steam supply system is broken into two distinct analyses: a Helmholtz solution within the steam dome and an acoustic circuit analysis in the main steam lines. This section of the report highlights the two approaches taken here. These analyses are then coupled for an integrated solution.

2.1 Helmholtz Analysis A cross-section of the steam dome (and steam dryer) is shown below in Figure 2.1, with BFNl dimensions as shown [4]. The complex three-dimensional geometry is rendered onto a uniformly-spaced rectangular grid (with mesh spacing of approximately 1.5 inches to accommodate frequency from 0 to 250 Hz in full scale), and a solution, over the frequency range of interest, is obtained for the Helmholtz equation alp a2p a 2 p2 W2 2 S-+ z +--P =V2P+-a2 P=o where P is the pressure at a grid point, (o is frequency, and a is acoustic speed in steam.

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f g Figure2.1. Cross-sectional description of the steam dome and dryer, with the BFN1 dimensions of a' = 16.0 in, b = 16.0 in, c' = 24.0 in, c = 14.5 in, d = 17.5 in, e =

15.5 in, f= 74.0 in, g = 163.0 in, i = 97.5 in, j = 189.0 in, k = 121.0 in, and R =

125.7 in (dimensions deduced from [4] to within 1.5 inches).

2

This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information This equation is solved for incremental frequencies from 0 to 250 Hz (full scale), subject to the boundary conditions dP dn normal to all solid surfaces (the steam dome wall and interior and exterior surfaces of the dryer),

dP ico dn a normal to the nominal water level surface, and unit pressure applied to one inlet to a main steam line and zero applied to the other three.

2.2 Acoustic Circuit Analysis The Helmholtz solution within the steam dome is coupled to an acoustic circuit solution in the main steam lines. Pulsation in a single-phase compressible medium, where acoustic wavelengths are long compared to transverse dimensions (directions perpendicular to the primary flow directions), lend themselves to application of the acoustic circuit methodology. If the analysis is restricted to frequencies below 250 Hz, acoustic wavelengths are approximately 8 feet in length and wavelengths are therefore long compared to most components of interest, such as branch junctions.

Acoustic circuit analysis divides the main steam lines into elements which are each characterized, as sketched in Figure 2.2, by a length L, a cross-sectional area A, a fluid mean density p, a fluid mean flow velocity U, and a fluid mean acoustic speed a.

- A - element cross-sectional area 0 L -

I Xn Figure 2.2. Schematic of an element in the acoustic circuit analysis, with length L and cross-sectional area A.

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information Application of acoustic circuit methodology generates solutions for the fluctuating pressure Pn and velocity un in the nth element of the form Pn = [AneikinXn +Bneik2nXn eimt Un =-2I ((0+7Unk 1 n )AneiklnXn + (°+Unk2 n)Bneik2nXn ]ec"t where harmonic time dependence of the form ei"'t has been assumed. The wave numbers k1 n and k2, are the two complex roots of the equation 2 .+fn Un 1 0 2

k -2 (+ +Unk, ) _(o 2 +Unkn =0 Dna a where f, is the pipe friction factor for element n, Dn is the hydrodynamic diameter for element n, and i = 4-. A, and B, are complex constants which are a function of frequency and are determined by satisfying continuity of pressure and mass conservation at element junctions.

The solution for pressure and velocity in the main steam lines is coupled to the Helmholtz solution in the steam dome, to predict the pressure loading on the steam dryer.

The main steam line piping geometry is summarized in Table 2.1.

Table 2.1. Main steam line lengths at BFN1. Main steam line diameter is 26 inch (ID = 24.0 in).

Main Steam Line Length to First Length to Second Strain Gage Strain Gage Measurement (ft) Measurement (ft)

A 9.5 34.5 B 9.5 34.5 C 10.0 34.5 D 9.5 34.5 2.3 Low Frequency Contribution

[(3 (3)))

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information

3. Input Pressure Data Strain gages were mounted on the four main steam lines of BFN 1. Two data sets were examined in this analysis. The first data set recorded tlhe strain at Current Licensed Thermal Power (100% power level or CLTP), and the second data set recorded the strain at near-zero voltage on the strain gages (EIC noise) at CLTP. The data were provided in the following files:

Data File Name Power Level Voltage 20070608155619 100% 10.0 V 20070608155258 100% 0.01 V (EIC)

The strain gage signals were converted to pressures by the use of the conversion factors provided in [5] and summarized in Table 3.1. Exclusion frequencies were used to remove extraneous signals, as also identified in [5] and subsequent emails, and summarized in Table 3.2.

The electrical noise was removed by applying the function PS(()= PSN(o)I I )SN P"N(0)

(O) 1 where Ps(co) is the CLTP signal PSN(CO) corrected for electrical noise PN(CO), computed as a function of frequency (o, and IPN(O)/PsN(O)l can be no larger than 1.0. These signals were further processed by the coherence factor and mean filtering as described in [2]. Coherence at CLTP is shown in Figure 3.1.

The resulting main steam line pressure signals may be represented in two ways, by their minimum and maximum pressure levels, and by their PSDs. Table 3.3 provides the pressure level information, after removal of EIC and exclusion filtering, while Figures 3.2 to 3.5 compare the frequency content at the eight measurement locations. The frequency content around 218 Hz has been removed from the signals plotted here, in anticipation of the use of inserts in the blank standpipes on main steam lines A and D [3] to mitigate this load.

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information Table 3.1. Conversion factors from strain to pressure [5]. Channels are averaged to give the average strain.

Strain to Pressure Channel Channel Channel Channel (psid/kstrain) Number Number Number Number MSL A Upper 2.997 1 2 3 4 MSL A Lower 3.027 5 6 7 8 MSL B Upper 3.034 9 10 11 12 MSL B Lower 2.993 13 14 15 16 MSL C Upper 2.912 17 18 19 20 MSL C Lower 2.962 21 22 23 24 MSL D Upper 2.959 25 26 27 28 MSL D Lower 3.007 29 30 31 32 Table 3.2. Exclusion frequencies for BFN1 strain gage data, as suggested in [5] and subsequent emails. VFD = variable frequency drive. Recirc = recirculation pumps.

Frequency Interval (Hz) Exclusion Cause 0-2 Mean 59.8 - 60.2 Line Noise 119.9 - 120.1 Line Noise 179.8 - 180.2 Line Noise 239.9 - 240.1 Line Noise 51.3-51.7 VFD (Ix) 127.0 - 128.5 Recirc Pumps A, B Speed (5x) 217.9 - 219.6 Standpipe Excitation Table 3.3. Main steam line (MSL) pressure levels in BFN1.

Minimum Maximum RMS Pressure (psid) Pressure (psid) Pressure (psid)

MSL A Upper -1.82 1.95 0.43 MSL A Lower -1.90 2.11 0.46 MSL B Upper -1.92 2.34 0.47 MSL B Lower -2.06 2.19 0.51 MSL C Upper -2.17 2.42 0.53 MSL C Lower -2.62 2.39 0.58 MSL D Upper -2.08 2.09 0.51 MSL D Lower -1.93 2.25 0.46 6

This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information BFNI: MSL A 1

0.8 C.)

0.6 0

0 0.4 0.2 0

0 50 100 150 200 250 Frequency (Hz)

BFNI: MSL B 1

0.8 0

C.)

0.6 0

0 0 0.4 0.2 0

0 50 100 150 200 250 Frequency (Hz)

Figure 3. Ia. Coherence between the upper and lower strain gage readings at BFN 1: main steam line A (top); main steam line B (bottom).

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information BFNI: MSL C 1

0.8 0D 0.6 0.4 0.2 0

0 50 100 150 200 250 Frequency (Hz)

BFNI: MSL D 1

0.8 0

0.6 0

0 0 0.4 C,)

0.2 0

0 50 100 150 200 250 Frequency (Hz)

Figure 3. lb. Coherence between the upper and lower strain gage readings at BFNI: main steam line C (top); main steam line D 8

This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information BFNI: MSL A Upper 0.1 0.01 N

Cl, 0.001 0.0001 10-5 10.6 0 50 100 1"50 200 250 Frequency (Hz)

BFNI: MSL A Lower 0.1 0.01 N

Cl 0.001

-o4 0.0001 10.5 10-6 0 50 100 150 200 250 Frequency (Hz)

Figure'3.2. PSD comparison of pressure measurements on main steam line A at strain gage locations upper (top) and lower (bottom).

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information BFNI: MSL B Upper 0.1 0.01 N

0.001 0.0001 105 10-6 0 50 100 150 200 250 Frequency (Hz)

BFNI: MSL B Lower 0.1 0.01 N

tCl 0.001

-e*

0.0001 10-5 10-6 0 50 100 150 200 250 Frequency (Hz)

Figure 3.3. PSD comparison of pressure measurements on main steam line B at strain gage locations upper (top) and lowe 10

This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information BFNI: MSL C Upper 0.1 0.01 N

0.001 0.0001 10.5 10.6 0 50 100 150 200 250 Frequency (Hz)

BFNI: MSL C Lower 0.1 0.01 Nq 0.001 0.0001 105 10-6 0 50 100 150 200 250 Frequency (Hz)

Figure 3.4. PSD comparison of pressure measurements on main steam line C at strain gage locations upper (top) and lower (bottom).

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information BFNI: MSL D Upper 0.1 0.01 N

0.001 0.0001 10.5 10.6 0 50 100 150 200 250 Frequency (Hz)

BFNI: MSL D Lower 0.1 N 0.01 0.001 CI) 0.0001 10.5 10.6 0 50 100 150 200 250 Frequency (Hz)

Figure 3.5. PSD comparison of pressure measurements on main steam line D at strain gage locations upper (top) and lower (bottom).

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information

4. Results The measured main steam line pressure data were used to drive the validated acoustic circuit methodology for the BFN1 steam dome coupled to the main steam lines to make a pressure load prediction on the BFN1 dryer. A low resolution load, developed at the nodal locations identified in Figures 4.1 to 4.4, produces the maximum differential and RMS pressure levels across the dryer as shown in Figure 4.5. PSDs of the peak loads on either side of the dryer are shown in Figure 4.6.

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information Figure 4.1. Bottom plates pressure node locations (low resolution), with pressures acting downward in the notation defined here.

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information 47 Figure 4.2. Top plates pressure node locations (low resolution), with pressures acting downward in the notation defined here.

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information Figure 4.3. Vertical plates: Pressures acting left to right on panels 6-11, 22-27, 38-43, and 50-54; acting right to left on panels 64-69, 80-85, and 94-99 (low resolution).

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information 7 69-99 g- 1  ;,37 A-S63 79 -

/96 I

119 77 93~

• '*~2'

- 5 C- 97 xýL 83 2541 1 67'

'101

'3, 6 194 20 I I U 100 2 62 4 2

---

----- 76 34 Figure 4.4. Skirt plates: Pressure acting outward on the outer dryer 0'/180' surfaces and the skirt (low resolution).

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information

((I (3)]

Figure 4.5. Predicted loads on the low resolution grid identified in Figures 4.1 to 4.4, as developed by the Modified Bounding Pressure model, to 250 Hz. Low-numbered nodes are on the C-D side of the dryer, while high-numbered nodes are on the A-B side of the dryer.

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information (3)))1 Figure 4.6. PSD of the maximum pressure loads predicted on the C-D side of the BFN1 dryer (top) and A-B side of the BFN1 dryer (bottom).

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information

5. Uncertainty Analysis The analysis of potential uncertainty occurring at BFN 1 consists of several contributions, including the uncertainty from collecting data on the main steam lines at locations other than the locations on Quad Cities Unit 2 (QC2) and the uncertainty in the Modified Bounding Pressure model. QC2 dryer data at Original Licensed Thermal Power (OLTP) conditions were used to generate an uncertainty analysis of the Acoustic Circuit Methodology (ACM) [2] for BFN1.

The approach taken for bias and uncertainty is similar to that used by Vermont Yankee for power uprate [6]. In this analysis, six "averaged pressures" are examined on the instrumented replacement dryer at QC2: averaging pressure sensors P1, P2, and P3; P4, P5, and P6; P7, P8, and P9; P1O, P11, and P12; P18 and P20; and P19 and P21. These pressure sensors were all on the outer bank hoods of the dryer, and the groups are comprised of sensors located vertically above or below each other.

Bias is computed by taking the difference between the measured and predicted RMS pressure values for the six "averaged pressures", and dividing the mean of this difference by the mean of the predicted RMS. RMS is computed by integrating the PSD across the frequency range of interest and taking the square root I I (RMSmcasured

- RMSpredicted)

BIAS = N (5.1) 1N-E M predicted where RMSineasured is the RMS of the measured data and RMSpredicted is the RMS of the predicted data. Summations are over the number of "averaged pressures", or N = 6.

Uncertainty is defined as the fraction computed by the standard deviation 1 Z (VRMSmeasured - R-MSpredicted )2 UNCERTAINTY - 1 (5.2)

N RMS predicted ACM bias and uncertainty results are compiled for specified frequency ranges of interest, as directed by [7, 8] and summarized in Table 5.1. Other random uncertainties, specific to BFN1, are summarized in Table 5.2 and are typically combined with the ACM results by SRSS methods to determine an overall uncertainty for BFN 1.

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information Table 5.1. BFN1 bias and uncertainty for specified frequency intervals. A negative bias indicates that the ACM overpredicts the QC2 data in that interval.

Er (3)))1 Table 5.2. Bias and uncertainty contributions to total uncertainty for BFN I plant data.

Er (3)))1 21

This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information

6. Bump-Up Factors for 120% OLTP Power Subscale testing [3] provides the data with which to develop bump-up factors that relate unsteady main steam line pressures at CLTP conditions to those anticipated at 120% OLTP power. This bump-up factor, for each strain gage location, is applied to full-scale CLTP strain gage data collected on the main steam lines to obtain an estimate of the full-scale 120% OLTP power strain gage data near the standpipe/valve excitation frequency expected. A velocity-squared bump-up factor is used when removed from the excitation frequency. The 120% OLTP power strain gage data is then used to estimate steam dryer stresses at this power level, using the acoustic circuit model for dryer loads and a finite element model of the dryer for stress predictions.

The selected subscale.tests are identified in Table 6.1.

The bump-up factor is calculated as a function of frequency (averaging the two CLTP data results and the two 120% OLTP data results), converted from subscale to full scale, with the equation Bump-Up Factor IPSD 20 (6.1)

- PSDCLTP and involves dividing the 120% OLTP PSD at each frequency by the CLTP PSD at that frequency, and taking the square root. This equation is used for each of the eight strain gage locations in the frequency interval from 100 Hz to 120 Hz, thereby encompassing the anticipated standpipe/valve excitation frequency interval. Outside this interval, a velocity-squared bump-up factor of 1.35, based on anticipated and actual in-plant flow rate at BFN 1, is used. The resulting bump-up factors are plotted in Figure 6. 1.

The bump-up factor at each strain gage location is used to multiply the strain gage readings at that location in the plant at CLTP conditions, on a frequency-by-frequency basis, to obtain the estimated main steam line strain gage readings at that location in the plant at 120%

OLTP power. The subsequent dryer loads developed from the acoustic circuit model would be provided to a finite element model of the dryer for stress predictions at 120% OLTP power.

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information Table 6.1. Summary of one-eighth scale tests used to develop bump-up factors.

BFNl File Names [31 CLTP bl-f491-123 bl-f491-124 120% Power bl-f491-127 bl-f491-128 (3)]

Figure 6.1. Bump-up factors developed from BFN1 subscale data for 120% OLTP power. The eight locations are shown by the eight pressure transducer identifiers.

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information.

7. Conclusions The C.D.I. acoustic circuit analysis, using full-scale measured data for BFNI:

a) ((

(3)))

b) Predicts that the loads on dryer components are largest for components nearest the main steam line inlets and decrease inward into the reactor vessel.

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8. References

1. Continuum Dynamics, Inc. 2005. Methodology to Determine Unsteady Pressure Loading on Components in Reactor Steam Domes (Rev. 6). C.D.I. Report No. 04-09 (C.D.I. Proprietary).

2. Continuum Dynamics, Inc. 2007. Bounding Methodology to Predict Full Scale Steam Dryer Loads from In-Plant Measurements, with the Inclusion of a Low Frequency Hydrodynamic Contribution (Rev. 0). C.D.I. Report No. 07-09 (C.D.I. Proprietary).

3. Continuum Dynamics, Inc. 2008. Flow-Induced Vibration in the Main Steam Lines at Browns Ferry Nuclear Units 1 and 2, With and Without Acoustic Side Branches, and Resulting Steam Dryer Loads (Rev. 0). C.D.I. Report No. 08-14 (C.D.I. Proprietary).

4. Browns Ferry Unit 1 Drawings. 2006. Files: 729E229-1.tif, 729E229-2.tif, and 729E229-3.tif. BFNI Email from G. Nelson dated 07 March 2006.

5. Structural Integrity Associates, Inc. 2007.. Browns Ferry Unit 1 Main Steam Line 100%

CLTP Strain Data Transmission. SIA Letter Report No. KKF-07-012.

6. Communication from Enrico Betti. 2006. Excerpts from Entergy Calculation VYC-3001 (Rev. 3), EPU Steam Dryer Acceptance Criteria, Attachment I: VYNPS Steam Dryer Load Uncertainty (Proprietary).

7. NRC Request for Additional Information on the Hope Creek Generating Station, Extended Power Uprate. 2007. TAC No. MD3002. RAI No. 14.67.

8. NRC Request for Additional Information on the Browns Ferry Generating Station, Extended Power Uprate. 2009. RAI No. 204/168.

9. Structural Integrity Associates, Inc. 2007. Evaluation of Browns Ferry Unit 1 Strain Gage Uncertainty and Pressure Conversion Factors (Rev. 0). SIA Calculation Package No. BFN-12Q-302.

10. Continuum Dynamics, Inc. 2005. Vermont Yankee Instrument Position Uncertainty. Letter Report Dated 01 August 2005.

11. Exelon Nuclear Generating LLC. 2005. An Assessment of the Effects of Uncertainty in the Application of Acoustic Circuit Model Predictions to the Calculation of Stresses in the Replacement Quad Cities Units 1 and 2 Steam Dryers (Revision 0). Document No. AM-21005-008.

12. Continuum Dynamics, Inc. 2007. Finite Element Modeling Bias and Uncertainty Estimates Derived from the Hope Creek Unit 2 Dryer Shaker Test (Rev. 0). C.D.I. Report No. 07-27 (C.D.I. Proprietary).

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This Document Does Not Contain Continuum Dynamics, Inc. Proprietary Information

13. NRC Request for Additional Information on the Hope Creek Generating Station, Extended Power Uprate. 2007. RAI No. 14.79.

14. NRC Request for Additional Information on the Hope Creek Generating Station, Extended Power Uprate. 2007. RAI No. 14.110.

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