ML063110167

Attachment 2 - CDI Technical Memo 06-23P (Non-Proprietary) Comparison of Hope Creek and Quad Cities Steam Dryer Loads at EPU Conditions, Revision 0, Dated September 2006

ML063110167
Person / Time
Site:	Hope Creek, Quad Cities
Issue date:	09/30/2006
From:	Continuum Dynamics
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LCR H05-01, Rev. 1, LR-N06-0418 CDI 06-23P
Download: ML063110167 (7)

Text

Attachment 2 LR-N06-0418 LCR HOS-01, Rev. I CDI Technical Memo 06-23P (Non-Proprietary)

Comparison of the Hope Creek and Quad Cities Steam Dryer Loads at EPU Conditions Revision 0, dated September 2006

This Report Does Not Contain Continuum Dynamics, Inc. Proprietary Information C.D.I. Technical Memorandum No.06-23P Comparison of the Hope Creek and Quad Cities Steam Dryer Loads at EPU Conditions Revision 0 Prepared by Continuum Dynamics, Inc.

34 Lexington Avenue Ewing, NJ 08618 September 2006

This Report Does Not Contain Continuum Dynamics, Inc. Proprietary Information Introduction Steam flow in the main steam lines can excite oscillations in main steam line standpipes by a flow induced instability over the inlet to the standpipes. These standpipes connect safety and relief valves to the main steam lines to provide pressure relief capability. Quad Cities Units 1 and 2 (QCI and QC2, respectively) appear to be the only domestic nuclear power plants where this excitation leads to large loads. In the Quad Cities units these oscillations - which originate in the main steam lines - propagate upstream into the steam dome and result in large steam dryer pressure loads at discrete frequencies. These loads for QC2 are now well documented (although the data remain proprietary) and are now reasonably understood (although prediction of amplitudes of these loads from first principles is not possible). A steam dryer load definition for the Hope Creek Nuclear Power Station (HC1) was developed by C.D.I. from subscale tests (Ref.

1), and the purpose of this note is to compare the measured steam dryer loads at QC2 (Ref. 2) with that measured/predicted for HCl at EPU conditions. This memo documents a limited comparison ofthese data.

Quad Cities Unit 2 and Hope Creek Unit I Selected PSDs Shown in Figure 1 are the Power Spectral Density functions for the measured differential pressure load on the QC2 steam dryer and the measured/predicted load for the HCI dryer at EPU conditions. Nodes 7 (HC1) and 17 (QC2) are on the centerline between MSL C and D at the intersection of the cover plate with the outer bank hood. Nodes 99 (HC1) and 133 (QC2) are on the centerline between MSL A and B at the intersection of the cover plate with the outer bank hood. ((

(3 )). It is noted in passing that the standpipe resonant frequency for HC1 was predicted to be at 120 Hz and a peak can be seen in the PDS plots for HCI at 120 Hz. ((

_(3].

Time histories of the pressure differences are shown in Figure 2 and Figure 3 to compare HCI and QC2 differential pressure loads. ((

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This Report Does Not Contain Continuum Dynamics, Inc. Proprietary Information Figure 1. Comparison of PSDs of pressure difference at EPU conditions for Hope Creek Unit 1 (scaled from subscale experiments) and Quad Cities Unit 2.

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This Report Does Not Contain Continuum Dynamics, Inc. Proprietary Information HCI: Node 7 0.4 1 0.3 ----------~-- ~- -..........-...........----

0.2------. -- - -

0.1--

0

-0.1 --

-0 .2- ... - - ........ .. .. .

-0.3

-0.4 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 Time (sec)

(3 Figure 2. Time histories of pressure difference across the dryer at nodes 7 (HC1) and 17 (QC2) at EPU conditions. [f .(3 ))

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This Report Does Not Contain Continuum Dynamics, Inc. Proprietary Information HCI: Node 99 0.6 0.4 0.2 IE5 U-4 0 0i M. -0.2

-0.4

-0.6 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 Time (sec)

((

-3*1]

Figure 3. Time histories of pressure difference across the dryer at nodes 99 (HC1) and 133 (QC2) at EPU conditions. [F -(31].

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This Report Does Not Contain Continuum Dynamics, Inc. Proprietary Information Quantitative Comparison of the Loads Tabulated below is a quantitative comparison of the two loads for HCI and QC2.

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

HC 1: Node 7 -0.42 0.39 0.12 HC1: Node 99 -0.45 0.42 0.13

((I

.(3))) This evaluation does not take credit for the fact that the HCI EPU load is conservative and has been discussed elsewhere.

References

1. Continuum Dynamics, Inc. 2006. Estimating High Frequency Flow Induced Vibration in the Main Steam Lines at Hope Creek Unit 1: A Subscale Four Line Investigation of Standpipe Behavior. C.D.I. Report No. 06-16 (Revision 1).

2. Continuum Dynamics, Inc. 2006. Bounding Methodology to Predict Full-Scale Steam Dryer Loads from In-Plant Measurements. C.D.I. Proprietary Report No.05-28P (Revision 1).

3. Continuum Dynamics, Inc. 2006. High and Low Frequency Steam Dryer Loads by Acoustic Circuit Methodology. C.D.I. Proprietary Technical Memorandum No.06-25P.

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