ML20210Q859
| ML20210Q859 | |
| Person / Time | |
|---|---|
| Issue date: | 08/27/1997 |
| From: | Denning R NRC (Affiliation Not Assigned) |
| To: | Gupa V HOLTEC INTERNATIONAL |
| References | |
| REF-PT21-97 TAC-M99304, NUDOCS 9709020186 | |
| Download: ML20210Q859 (3) | |
Text
__
{
August 27, 1997 Mr. Vikram Gupa Quality Assurance Manager Holtec Intemational 555 Lincoln Drive West Marlton, New Jersey 08053
SUBJECT:
REQUEST FOR ADDITIONAL INFORMATION REGARDING HOLTEC PART 21 NOTIFICATION ON THE ANSYS COMPUTER CODE (TAC M99304)
Dear Mr. Gupa:
In your letter dated June 27,1997, Holtec Intemational submitted some information regarding the ANSYS computer code. The staff has reviewed this information and has identified the i
need for further information as discussed in the enclosed request for additionalinformation.
1 Please provide your response to the request so that we may continue our review of your submittal.
Please address any question you may have on this matter to Tom Greene of my staff. Mr.
Greene may be reached by phone (301) 415-1175.
Sincerely.
Original signed b Ror'ert L. Denning,yActing Chief Events Assessment and Generic Communication Branch Division of Reactor Program Management Office of Nuclear Reactor Regulation
Enclosure:
As stated D F o!>,,
cc: Y. Kim R. Rothman G. Bagchi L d I'OIMl G. Lainas B. $ heron etcpM.M *l J. Roe Distribution:
- Central File PDP PECB R/F
/(
C 1 fl ~ 3 $
DRPM R/F DOCUMENT NAME: G:\\ TAG \\LETHOT T3 receive a copy of this document. Indicate in the box:
"C" = Copy without enclosures "E" = Copy with enclosures "N" = No copy 0FFICE PECB l
c.
(A)SC:PECB l p (A)f:ff,11T l l
l NAME TGreene r4 CPetronerp RD(rficy U DATE 08/.u:/97t#
08/w/97 08/)d97 08/ /97 08/ /97 0FFICIAL RECORD COPY I.ll,I,I,I!I !IUll. I.I 9709020186 970827 97'/ Y
- .EC E
_ [
PT21 Nb b
l' REQUEST FOR ADDITIONAL INFORMATION ON THE N0LTEC PART 21 NOTIFICATION ON THE ANSYS COMPlfTER CODE Civil Enaineerina and Geosciences Branch Division of Enaineeriqq 1.
In Reference 1 you indicated that the ANSYS computer code is not suitable for sImulatir.g complex nonlinear transient problems (i.e.,
i d namic modeling of spent fuel racks)ANSYS code and developed your ow You further indicated that for t is reason, you stopped the use the code DYNARACK, over the past ten years for dynamic analysis of free-l standing underwater structures.
You are requested to provide *the l
l following:
a)
What are the...;deling techniques tdopted in the ANSYS and DYNARACK codes and what are the differences between the two modeling techniques? Provide detailed technical discussion, b)
Provide an explanation of: (1) why the modeling technique of DYNARACK guarantees a stable, convergent, accurate solution for free-standing rack structures and (2) why the modeling technique of ANSYS does not do the same, c)
Are there any analytical evaluations and experimental tests that support your technical conclusions discussed in Part b) above?
If there are, provide the references.
d)
Are your conclusionL on the ANSYS modeling technique applicable for both single-and multi-rack analyses?
If they are only applicable to a multi-rack analysis, explain how the ANSYS technique works for a tiegle-rack analysis, e)
Provide any other technical concerns about the ANSYS computer code in addition to the mc aling technique discussed above for a three-dimensional, nonlinear, transient free-standing rack analysis.
2.
In Reference 1, you indicated that the deficiencies of the ANSYS computer code were detected when the ANSYS code was being used for a-classified Department of Defense / Department of Energy (DoD/ doe) project-You are requested to provide the following information.
Please do not discuss any classified information.
a)
Indicate whether analysis was single-and/or multi-rack analysis, b)
Describe in detail the physical model including dimensions, the applied loading conditions, the boundary conditions, the material-properties of the model and how you used the ANSYS computer code in the analysis.
1
's
?.
i 2
c)
We assume that you used the DYNARACK code to complete the project or t.t least to confirm the ANSYS analysis results, after you found l
that the ANSYS code suffered from convergence and stability problems.
Provide a summary of the complete analysis results (i.e., stresses, displacements, hydrodynamic pressure distribution, locations of the maximum responses, etc.) in a tabular form for the single-and/or multi-rack analyses using the DYNARACK and the ANSYS codes.
E i
Reference:
1.
Letter, dated June 27, 1997, from V. Gupta of HOLTEC to T. Greene of PECB/NRC, " Request for a Technical Review of a Draft information Notice Regarding Erroneous Results from ANSYS 5.0A and ANSYS 5.1 Computer Codes."
i r
i 1
l 1
l s
h r*+wT 7
myw4-7-7
-1g--
--?
3rN -,
a wt
-e-$
w--y g m 4
pre----+eney-%
9--Td?
ewy
- 'm*
h-'efr>W7*
w'