ML20040D892

Response to Question on Effect of Spacer Grid Design on DNBR Prediction,Waterford Steam Electric Station,Unit 3.

ML20040D892
Person / Time
Site:	Waterford
Issue date:	01/31/1982
From:	ABB COMBUSTION ENGINEERING NUCLEAR FUEL (FORMERLY
To:
Shared Package
ML19297F297	List: ML20040D886 ML20040D892
References
NUDOCS 8202020357
Download: ML20040D892 (4)

Text

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b Encl. (1) to C.CE 7459 l

RESPONSE to

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QUESTION on EFFECT of SPACER GRID DESIGN on DNBR PREDICTI.ON WATERFORD STEAM ELECTRIC STATION UNIT NO. 3 JANUARY,1982 h ts N NolN NG N

I LEGAL NOTICE THIS REPORT WAS PREPARED AS AN ACCOUNT OF WORK SPONSORED BY COMBUSTION ENGINEERING, INC. NEITHER COMBUSTION ENGINEERING NOR ANY PERSON ACTING ON ITS BEHALF:

A. MAKES ANY WARRANTY OR REPRESENTATION, EXPRESS OR IMPLIED INCLUDING THE WARRANTIES OF FITNESS FOR A PART!CULAR PURPOSE OR MERCHANTA81UTY, WITH RESPECT TO THE ACCURACY, COMPLETENESS, OR USEFULNESS OF THE INFORMATiON CONTAINED IN THIS REPORT, OR THAT THE USE OF ANY INFORMATION, APPARATUS, METHOD, OR PROCESS DISCLOSED IN THIS REPORT MAY NOT INFRINGE PRIVATELY OWNED RIGHTS;OR

8. ASSUMES ANY UA81UTIES WITH RESPECT TO THE USE OF,OR FOR DAMAGES RESULTING FROM THE USE OF, ANY INFORMATION, APPARATUS, METHOD OR PROCESS OlSCLOSED IN THIS REPORT.

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- . Non-Proprietary Enclosure R:sponse to Question on Effect to C-CE-7458 of Spacer Grid Design on DNBR

= Prediction i

Question:

Demonstrate that the final spacer grid design has a negligible effect on MDNBRs predicted by the Waterford 3 FSAR Thermal Margin model, e

1 Response : l t

- Co:nparative Simplified TORC (S-TORC) analyses were performed utilizing both the FSAR and Design models. The FSAR S-TORC model contains one Inconel while the spacer grid and 10 standard grids with loss coefficients of { Design model -

dependent loss coefficients. At nominal conditions, these Reynolds number dependent relationships , yield loss coefficients of:

K (Inconel grid) =

K (HID-1 grid) =,

The FSAR S-TORC model was used to iterate on power to a MDNBR of 1.190.

This heat flux was then inserted into the comparable design S-TORC model to calculate a MDNBR. As can be seen from Table i the new spacer grid design with revised loss coefficients has a negligible effect on MDNBR.

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Response to Question on Effect Non-Proprietary' Enclosure of Spacer Grid Design on DNBR to C-CE-7458 -

Prediction

- TABLE 1: Comparison of FSAR and Design S-TORC MDNBRs

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Inlet femp. System Pressure Core Average Core Average Axial Power TORC Model MDNBR Quality 0F psia Heat Flux Shape 9 MDNBR Mass Velocit{es lb/hr-ft2x10 Btu /h; -f t2 .

553 2250 2.6394 Bottom

• FSAR 100% of Design Peaked Design , ,'

Core Flow Symmetric ** FSAR Cosine Design Top ** FSAR Peaked Design 1750 2.0951 Bottom

• FSAR 80% of Design Peaked Design Core Flow l

Symmetric ** FSAR ,

Cosine Design -

Top ** FSAR

__ _ Peaked Design

,r o i

• MDNBR occurring in lower half of core

• =MDNBR occurring in upper half of core i

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