ML20045D112
| ML20045D112 | |
| Person / Time | |
|---|---|
| Site: | 05200003 |
| Issue date: | 04/16/1993 |
| From: | Catton I Advisory Committee on Reactor Safeguards |
| To: | Advisory Committee on Reactor Safeguards |
| References | |
| ACRS-2869, NUDOCS 9306250342 | |
| Download: ML20045D112 (55) | |
Text
CERTIFIED BY:
E DATE ISSUED: 4/5/93 "Ivan Cdtton - 4/16/93 Odu 4%9 0
ADVISORY COMMITTEE ON REACTOR SAFEGUARDS
[W [kf3 THERMAL HYDRAULIC PHENOMENA SUBCOMMITTEE MEETING:
REVIEW OF RELAPS/ MOD 3 CODE ISSUES RELATED TO AP600 MODELING MARCH 4-5, 1993 IDAHO FALLS, IDAHO PURPOSE:
The purpose of the meeting was to review the status of the PWR version of the NRC-RES RELAP5/ MOD 3 (R/5) code, with emphasis on discussion of the RES analytical programs in support of the NRC's certification effort for the Westinghouse AP600 passive plant design.
ATTENDEES:
Principal meeting attendees included the following:
ACBS NRC-RES I.
Catton, Chairman B.
Sheron P.
Davis, Member L.
Shotkin T. Kress, Member D.
Bessette R.
Seale, Member N. Lauben E. Wilkins, Member D.
Solberg "V.J." Dhir, Consultant V.
3chrock, Consultant INEL D. Ward, Consultant G.
Johnsen W.
Wulff, Consultant R. Wagner N.
Zuber, Consultant M. Modro C.
Slater Penn. State V.
Berta A.
Baratta R.
Beelman A listing of attendeen who signed the meeting roster is attached to the Office Copy of these Minutes.
l Meetina Hichlichts. Aareements, and Reauests Openino Comments-I. Catton. Chairman Dr. Catton noted that the principal purpose of the meeting is to identify the thermal hydraulic (T/H) phenomena of importance to the modeling of AP600 safety analyses.
The Subcommittee also wants to determine the status of the development Efort for the RES R/5 code.
' During the meeting, numerous action items were generated, as were requests made for copies of reports, Papers, etc.
A complete set of all Action Items / Follow-up matters resulting from this meeting are listed at the back of thes; Minutes.
4 9 /[ O O O j DESIGNATED ORIGIEAL hp 93(%250342 930416 8
9 PDR Certified 37
s T/H Phen. Sub. Mtg.
2 March 4-5, 1993 Dr. Wilkins noted for the record that he has been declared in conflict of interest with the company that operates the INEL i;
h (EG&G). Due to this, his participation will be limited to aiding L
the Subcommittee's information gathering efforts.
He will not participate in the Committee's decision-making effort concerning the subject matter of this meeting.
The Consultants made the following comments (RES responses also noted):
e Dr.Dhir noted the following issues of concern regarding the R/5 code:
- Ability to model condensation with and without natural circulation present
- Capability of drag models given low flow conditions
- Accuracy of heat transfer models in the presence of noncondensables
- Capability to properly model stratified flow in both the horizontal and vertical directions
- Ability to predict CHF at low flow / low power conditions Dr. Sheron said that RES will try to respond to the above issues, but noted that it would have been helpful to have received notice of them in advance of the meeting.
- Messrs Davis and Zuber commented on the limitations noted in the R/5 documentation and the fact that this documentation is out-of-date (draft, issued in 1990).
Dr. Sheron said that resource constraints have prevented fixing some of the known code deficiencies;. Mr. Solberg acknowledged the problem with the. timeliness of the documentation. RES is in the process of an update.
A revised code manual will be issued by.the end of this year. Mr. Schrock urged RES to scrutinize the references cited in the manual, as many appear to be incorrect.
)
Status of AP600 & SBWR T/H Research Programs - L. Shotkin NRC-RES Dr.
L.
Shotkin discussed the following:
(1) the T/H issues identified by NRC for the AP600 and SBWR and the status of associated research; (2) an update on RES's confirmatory research programs, (3) the status of newly-formed T/H Review Group, and (4) an overview of the AP600/SBWR research programs.
For the abcVe items, the following key NRC staff actions were noted:
e Initiation of modeling improvements to RES codes (R/5, RAMONA - see below).
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e e-T/H Phen. Sub. Mtg.
3 March 4-5, 1993 e Development of NRC Implementation Plan for review of AP600 i
and SBWR vendor testing programs.
e Evaluation of need for separate effects testing of T/H phenomena associated with AP600 surge line/ hot-leg performed
- l (see below).
o Coupling of T/H codes with containment analysis code (CONTAIN) to model RCS/ containment interactions for accident events.
[ Note: Dr. Sheron noted that W is not planning to couple its T/H codes with models of containment interactions.
He suggested that the Subcommittee explore this matter with H.]
e RAMONA is being modified to allow modeling of flow instabilities in the SBWR plant. This work should be complete by the beginning of 1994.
e The RES test programs (ROSA-V integral system test program and the SBWR reduced-scale low pressure loop) are being conducted to evaluate the potential for system interactions.
e Coupling of the CONTAIN code with RELAP5 to allow modeling of t.he heat removal processes ansociated with the AP600 and SBWR passive containment designs.
s e The ROSA-V test program is proceeding.
The final cost proposal is due from the Japanese contractor (Sumatomo Heavy i
Industries) by March 15, 1993. A major design improvement was made to the Primary Residual Heat Removal (PRHR) component.
RES plans to award a contract, in the June, 1993 timeframe, for construction of a small (low-pressure) test loop for conduct of confirmatory testing in support of the SBWR design certification review.
Figures 1 provide an overview of RES's AP600 and SBWR research programs.
Dr. Catton asked RES to contact P. Boehnert and advise as to when a meeting of the T/H Phenomena Subcommittee. would be timely, vis-a-vis the SRM requirement that the ACRS review the ROSA-V test program prior to initiation of testing.
RES is to provide the Subcommittee a copy of the scaling report being compiled for the ROSA-V test facility when it is available
(~
April 1, 1993).
e The Commission has approved the mission and membership of the independent T/H Review Group.
Five Members compose this Group: V.
- Ransom, G.
- Bankoff, J.
- Mahaffy, Y.
Hassan, and D.
Chapin.
RES plans to involve the-Group in the CSAU process for use of RELAP5 on AP600 modeling.
In response to questions, Dr. Sheron said that the Review Group's meetings will be open to ACRS representatives.
e 4-
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h T/H Phen. Sub. Mtg.
4 March 4-5, 1993 Code Develooment and Assessment Process for ALWR Modelina -
N.
Lauben. NRC-RES The RES code development and assessment proceF9 for use of RELAPS to model the AP600 and SBWR plants was ditnfund by N.
Lauben (RES).
Mr. Lauben noted that this process nAll be performed, consistent with the CSAU methodology.
However, given that the code is being modified while undergoing the CSAU method, RES has modified the CSAU approach being used here as well (Figures 3-4).
Mr. Lauben indicated that RES plans to complete this process by the end of 1993.
The expected cost is ~ $ 4-5M.
Dr. Catton said that RES needs to determine if multi-dimensional effects are important to the modeling of the AP600, and, if they are, how they are to be dealt with.
Mr. Schrock expressed concern that the integrity of the CSAU process may be corrupted by the pressures of schedule and cost constraints.
Dr.
Sheron acknowledged this concern and indicated that RES would do the best job possible here.
RELAP5 Documentation and Peer Review - D.
Bessette. NRC-RES D. Bessette described the details of the RELAP5 code documentation and the associated peer review of same.
There will be six Volumes of documentation for RELAP5. Volumes I-V have been issued in draf t form; Volume VI (code numerics) is scheduled to be issued in June, 1993.
Peer reviews have been conducted on Volumes III IV
(" Developmental Assessment" and "Models and Correlations").. Peer reviews are now underway for Volumes V (" User Guidelines") and VI.
Figure 5 provides the details.
Dr. Catton requested copies of the above-noted peer review reports from RES when they are available.
There was extensive discussion centering on the fact that the above peer reviews were limited to comments on the adequacy of the documentation and not its content.
It was decided that the Subcommittee consultants would review the R/5 documentation, particularly Volumes III & IV, and provide a written report to Dr.
Catton.
These reports are to provide specific problems / concerns found with the code.
Mr.
Boehnert will consolidate the Consultants' reports for transmittal to RES.
Another meeting of the Subcommittee will be scheduled to discusa the disposition of these issues.
Revised Numberina Scheme for RELAP5 - R. Wagner. INEL INEL has instituted a revised numbering scheme for the R/S code.
i From now on, all future releases of the MOD 3 version of the code will be numbered consecutively.
The current released version has been designated RELAP5/ MOD 3.1.
Future versions will be designated
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5 March 4-5, 1993
" MOD 3.2",
and so on.
In response to Subcommittee questions, Dr.
Shotkin said that this change was made, in part, in response t o criticism received from the ACRS during a meeting held last December.
Identification of Kev Phenomena and Code Models for Analysis of AP600 Plant Desian - M. Modro. INEL Mr. Modro detailed the process that INEL used to identify the key phenomena and code models needed for successful analysis of the AP600 design using R/5.
This process was accomplished by use of the first portion of the CSAU method (Figure 6).
Key points noted in this discussion included:
e INEL has determined that the most challenging event for modeling of the AP600 design (CSAU Step 1) is a SBLOCA; specifically, a break in the Direct Vessel Injection line.
Dr. Zuber requested that INEL provide a detailed rationale for use of this case,.when the Subcommittee reviews the ROSA test program.
e The ranking of the phenomena for modeling AP600 (CSAU Step
- 3) was based on such activities as: available H test data, c
AP600 plant calculations, evaluations of the ROSA early facility, and reviews of the H OSU and SPES test facilities.
Phe.nomena were assigned rankings of "High",
" Medium", and
" Low".
" Low" ranked phenomena will be evaluated on a group basis.
" Medium" phenomena will be evaluated on a case-by-case l
basis; "High" ranked phenomena will be evaluated l
individually.
e Model improvements identified to date for RELAPS (CSAU Step 4) are listed on Figure 7.
INEL also established an i
assessment matrix to ensure that the components, systems, and j
behavior unique to AP600 will be evaluated.
Figures 8-11 detail this matrix.
Dr. Catton indicated that modeling of thermal stratification will be a key challenge.
The Chairman indicated that the Subcommittee will query H regarding the validation of their thermal stratification model.
There was detailed discussion of the expected fluid flow into the Core Makeup Tank.
The Subcommittee had been led to believe that given a LOCA, one should expect a steam jet to vent into the top of the CMT.
INEL representatives indicated that their modeling leads to the conclusion that this fluid will be water it. stead of steam.
If this is correct, the challenge to the code will be lessened for the modeling of this case.
AP600 Surae Line Offtake Model - A.
Baratta (NRC/Penn. Stalg1 I
4 T/H Phen. Sub. Mtg.
6 March 4-5, 1993
{-
Dr.
A.
Baratta discuused his activities associated with
[
determination of the ability of the R/5 code to model the flow seen j
at the junction of the AP600 pressurizer surge line and the hot leg 1
(Figure 12).
Two issues were investigated: the adequacy of the i
data base for evaluation of the R/5 code model, and, whether the existing models in the code need improvement.
i The issues pertaining to this issue and the two-phase flow regime transitions of interest were discussed.
Dr.
Baratta showed experimental data for the condition of high (generally > 0.8) gas i
off-take ratios (defined as flow out of the off-take/ flow into the mainline); essentially all of the liquid entrainment is independent i
of the orientation of either the off-take or mainline pipes.
f Further, Dr. Baratta said that calculations performed by the NRC l
with R/5 show results consistent with the above behavior.
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Drs. Catton and Zuber strongly suggested that RES perform R/5 i
calculations and compare the above results with test data to ensure -
the fidelity of the of f-take model.
Dr. Baratta indicated that the need for such a comparison is rendered moot due to the fact that one will always see high gas off-take ratios.
Dr. Catton objected i
to the logic evident in this response, noting that such logic has
{
served RES poorly in the past.
l Imorovements to R/5 for Modelina of Passive _wM Designs -
D.
Solbero (RES) /C. Slater (INEL)
[
Messrs. D. Solberg and C. Slater discussed the improvements made to i -
R/5 to support analyses of the AP600 and SBWR passive plant-designs.
At this time, two Phases of improvements have been 4
i effected.
Phase 1 was completed in February, 1993.
Phase 2 is.now I
underway and should be complete by October 1, 1993.
MOD 3.1 will be released in December of this year.
MOD 3.2 will be released following incorporation of the Phase 2 improvement effort.
Mr.
Solberg also noted that RES will be receiving ~ $500K/ year, for the next four years, from overseas members of the CAMP. program, which i
will be dedicated solely to the R/5 code maintenance effort.
Mr. C. Slater recounted the details of the difficulties encountered with the initial version of MOD 3, and the actions taken to correct the problems found.
Specific problems were found with various aspects of the condensation model and deficiencies were discovered in the time smoothing models.
Detailed discussion ensued concerning the specifics of the condensation model errors.
Dr.
Shotkin indicated that the fixes to the model errors noted above 2
i are temporary; the permanent fixes are part of the Phase 2 j
improvement effort.
Given this, the discussion was terminated.
i 4
R/S Model Imorovements for Passive Plant Calculations (First Tier)
- G. Johnsen (INEL) i-5 m-
e T/H Phen. Sub. Mtg.
7 March 4-5, 1993 Prior to Mr. Johnsen's presentation, Mr. R. Shumway (INEL) briefly.
reviewed the details of the' new wall condensation model incorporated into MOD 3 (Figure 13).
The Subcommittee expressed strong disapproval of this model, noting that it violates basic physical principles.
In subsequent discussion, Dr.
Sheron committed to providing the Subcommittee a' discussion of the rationale employed for the use of such models as those discussed above, vis-a-vis the problems encountered in assembling a complex systems code such a R/5.
Mr. Johnsen also committed to provide the detailed rationale for the use of the wall condensation model noted above.
Mr.
Johnsen noted that the passive plant designs share the following characteristics:
use of intentional RCS depressurization, large in-containment emergency cooling sources, and, the containment is integral to long-term decay heat removal.
As such, the behavior of these designs given an accident challenges the code models, which are, by and large, unproven (e.g.
long 3
transients, sharp interfaces, condensation with noncondensables present).
The following improvements were initially identified for R/5:
- Thermal stratification model e Boron transport
- Containment behavior e Condensation with and without noncondensables e Level tracking e Energy balance at a break Key points noted during the discussion of these improvements were:
- INEL initially believed that a thermal stratification model would be needed to successfully model the CMT behavior.
Subsequent investigation now leads the developers to question the need for such a model (Figure 14).
e The Subcommittee urged Mr.
Johnsen to evaluate the condensation model used in the code.
Mr. Johnsen indicated that they would be doing this;
- further, he. committed to providing the Subcommittee information on the validation of-the condensation model now in the code.
e The use of a second-order Gudenov correlation corrected a problem associated with numerical diffusion and allows tracking of a sharp borated water front (Figure 15).
Mr.
Schrock requested a copy of the INEL report that details the use of this correlation in the code.
T/H Phen. Sub. Mtg.
8 March 4-5, 1993 I
e R/5 has been linked to the CONTAIN code to allow modeling of the closely coupled behavior of the i 3 and containment.
Parallel virtual macnine software is being used to speed the-calculations of the coupled codes.
e A fix was incorporated into the code to - enhance the calculation of energy transfer at an abrupt area change (e.g.
pipe break - Figure 16).
e The containment condensing system used in AP600 requires a condensation model that accounts for the presence of air.
INEL incorporated an adaptation of the model of Vierow and Schrock for this purpose.
Mr. Schrock noted for the' record that he is in conflict of interest regarding his work for GE on this matter and refrained from advising the Subcommittee on this issue.
R/5 Model Improvements for Passive Plant Calculations (Second Tier)
- V.
Berta (INEL)
Mr. Berta discussed the second round (tier) of improvements slated.
for R/5 to enhance the modeling of the passive plants.
The specific improvements detailed were:
o Downcomer nodalization model e ADS and sparger condensation model e Steam separator model
- Spherical accumulator model e Computational improvement for long transients Figures 17-24 provide the details.
Regarding the first item, Dr. Zuber said that INEL cannot solve this problem with the use of nodalization; one must tackle the.
physics involved.
Mr Berta indicated that the pressures of.
schedule preclude use of a first-principles approach.
Dr. Catton suggested that INEL develop an empirical correlation. For the last item, Messrs. Catton and Schrock indicated that INEL needs to employ a quasi-steady state solution scheme.
Modelina of AP 600 PRHR/IRWST - G. Johnsen Mr. Johnsen discussed the problems being encountered with the modeling of the thermal hydraulics of the primary residual' heat removal system and in-containment refueling water storage tank
-(Figure 25).
He noted that the modeling'of this system presents many challenges including the following:
recirculation of'IRWST coolant in the vicinity of the PRHR tube bank, partial uncovery of PRHR tubes, nodalization of IRWST, and faulty donoring of air into IRWST (R/5 code problem).
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. T'/H Phen. Sub. Mtg.
9 March 4-5, 1993 Figure 26 shows the PRHR/IRWST nodalization diagram used in R/5.
There was extensive discussion regarding the details of the model.
Dr. Catton said that INEL would be better served to use a plume rise model (empirically based) rather than the finite difference model now employed in the code.
Dr. Shotkin indicated that H is planning a set of separate effects tests focusing on the T/H behavior of the PRHR.
He suggested that the Subcommittee investigate this program, as RES has concerns regarding the scaling rationale to be used by H here.
Mr. Johnsen indicated that the central problem being encountered in t
the modeling of this system is the inability of the code to model the thermal layer that is expected to be set up across the top of the pool when the PRHR is in use.
Mr. Schrock indicated that lumped-parameter models are available to capture this phenomenon; he (Schrock) committed to sending INEL some detailed information on this matter.
R/5 Ability to Model Horizontal Countercurrent Flow - G. Johnsen l
In response to concerns expressed by the Subcommittee on this item, Mr. Johnsen discussed the ability of R/5 to model the phenomenon of l
horizontal countercurrent flow.
He showed results of code calculations that he maintained demonstrate that the code has the capability to satisfactorily model this phenomenon (Figures 27-29).
Extensive Subcommittee discussion followed that centered on R/5's modeling capability in this matter. Drs. Catton and Zuber observed that the code appears to do a good job for the modeling of the hydrodynamics.
However, both also noted that modeling regime used in the stratified flow model will not allow for proper characterization of the heat transfer.
Dr. Catton asked if INEL l
has determined if modeling of the heat transfer for the case of stratified. flow in the RCS piping during long transients is important. Mr. Beelman (INEL) indicated that they will investigate this point via sensitivity studies.
Testino and Modelina of SGTR - M. Modro Mr. Modro briefly discussed the testing approach used to simulate a steam generator tube rupture (s) accident.
Figure 30 shows a schematic of the simulation approach to be used on ROSA.
Mr. Schrock noted that his principle concern with this matter is that R/5 does not, in his opinion, have a credible critical flow model that can treat the phenomenon of flashing in pipes.
Discussion ensued.
Mr. Johnsen indicated that INEL believes that j
the R/S critical flow model can address flashing in pipes, but conceded that the relevant documentation may not have been as complete as necessary.
He committed to investigate this matter.
I
T/H Phen. Sub. Mtg.
10 March 4-5, 1993 Additional discussion centered on the question of relating the key flow parameters for the experiment (ROSA) and the plant model.
Messrs. Shotkin and Modro indicated that RES will perform studies to relate these key modeling parameters.
AP600 Comoonent Modelino Issues - M. Modro Conti. 'ing an earlier discussion, Mr. Modro discussed the modeling approach being utilized in R/5 for the following AP600 components:
- ADS e Steam generator cold side plenum o Pressurizer e Downcomer Figures 31-35 provide the details of the INEL presentation.
Comments noted by the Subcommittee included the following:
o Concerning the modeling of the T/H phenomena seen at the steam generator outlet plenum, Mr. Schrock said that the model shown (Figure 33) will not provide a correct evaluation of the momentum flux.
e Concerning the nodalization of the downcomer, Dr. Catton indicated that if multi-dimensional effects are important, the current model in R/5 will'not work.
Mr. Modro indicated that INEL understands the limitations of this model, and they intend to use the COMMIX code as ' a benchmark.
Further discussion led to the admission by INEL that they had to'make j
use of ad-hoc correlations here, given the limitations of the available data.
Status of NRC-RES ROSA and SBWR Exoerimental Test Procrams -
D.
Bessette (RES) j i
The status of the RES test programs planned at the Japanese ROSA test facility (simulation of AP600 design), and the proposed SBWR small-scale test loop were described by Mr.
D. Bessette.
i For the ROSA program the following points were noted:
e NRC signed a letter contract with JAERI for use of ROSA on November 27, 1992.
The final contract is scheduled for signing on March 31, 1993.
Testing is scheduled to.begin early-1994.
e The scaling bases for ROSA include: 1/30 volume scale, full-height / full-pressure, and preservation of both piping pressure drops and component volumes.
Figure 34 lists the major ROSA AP600 components.
Mr.
Schrock urged INEL to perform a l
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T/H Phen. Sub. Mtg.
11 March 4-5, 1993 thorough analysis of the heat losses associated with ROSA, and the impact of these losses on the test results.
e Figures 35A-36 list the instrumentation planned for the ROSA tests.
There was some Subcommittee discussion that centered on the specifications to be applied to this instrumentation.
The Subcommittee advised RES/INEL to ensure that the specifications for the instrumentation are adequate to provide sufficient data quality, and that the test data are not compromised by cost constraints.
INEL indicated that they have had discussions with the Japanese on this matter.
Dr.
Catton said the Subcommittee would explore this issue in detail during a future Subcommittee meeting.
Mr. Schrack suggested that INEL consider installation of a Stores lens for visual observations of T/H phenomena.
e Facility characterization, or shakedown, tests are planned (Figure 37).
The actual test matrix is given on Figure 38.
e There was discussion on the details of the IRWST configuration and associated test instrumentation.
The Subcommittee noted that INEL must fully characterize the tank temperatures in order to ensure validation of the R/5 modeling.
The aspect ratios of the ROSA tank vary greatly from those of the prototypic plant.
Dr. Shotkin said that RES is studying the feasibility of installing additional instrumentation in the IRWST, but financial constraints may limit this effort.
Dr. Catton indicated that RES should not allow this test data to be compromised due to purported budget constraints.
Regarding the status of the proposed RES SBWR test facility, Mr.
Bessette noted that RES is now evaluating contract proposals.
As such, he is precluded from public discussion on the specifics of this matter.
He noted that the objective of the program is to obtain confirmatory test data from a
scaled facility that reproduces the major T/H phenomena of interest in a SBWR at low-l pressure conditions.
A contract to construct the facility should be awarded in June, 1993.
Testing should begin in August of next year.
Figures 39-40 provide some infonnation on the test program.
Prior to adjournment, Dr. Catton requested written reports from the Subcommittee Consultants.
[ Note:
see below for details of Consultants' report requests.]
The meeting was adjourned at 11:55 am, March 5, 1993.
FUTURE SUBCOMMITTEE ACTIONS ON THIS MATTER AND ITEMS FOR FOLLOW-UP j
Future Subcommittee Actions:
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T/H Phen. Sub. Mtg.
12 March 4-5, 1993 The ACRS Consultants present at the meeting will prepare a report that contains the following:
(1) identification of the critical thermal hydraulic issues of concern relative to AP600 safety analyses; (2) comments on their review of Volume IV of the RELAP5/ MOD 3 (R/5) Code Manual, and (3) general comments on'the development status of RELAP5.
For item (2), any problems / concerns identified should be specific in nature, and the problem items should be listed in descending order of priority in order to aid both RES's evaluation of their relative importance, and' establishment of a priority for their resolution-given resource constraints.
In all cases, the criticism should be constructive.
These reports should be provided to P.
Boehnert within 4-6 weeks.
Following receipt of these reports, and their transmittal to RBS for evaluation, another meeting of the T/H Phenomena Subcommittee will be scheduled to discuss the disposition of these issues.
Issues identified during this meeting as deserving further discussion in this regard included (in no particular priority) the following:
The need for a critical flow model in R/5 for the calculation of the phenomenon associated with fluid flashing i
occurring in long pipes.
1
- Further discussion of the surge line off-take model, with emphasis on assessment of this model against relevant test data expected to be generated by Westinghouse.
The basis (es) for the wall condensation model used in R/5.
A description of the data base used for code validation is also needed.
Modeling of the expected thermal stratification in the IRWST pool model (use of finite difference versus lumped parameter model).
Determination of the need for improvement in the heat transfer package included in the horizontal countercurrent flow model.
Confirmation that upon initial operation of the CMT, re-circulation leads to an insurge of RCS water that acts as a r
buffer to the (colder) tank water prior to the arrival of steam from the pressurizer.
- Development of the case for fidelity of the steam generator tube rupture model used in support of the ROSA-V tests.
Follow-uo Items:
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r T/H Phen. Sub. Mtg.
13 March 4.5, 1993
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1.
RES is _ to contact the ACRS Office (via P.
Boehnert) with suggested dates as to when a meeting _of the T/H Phenomena-
- Subcommittee should be scheduled in order to ensure the Committee's timely review of RES's AP600 confirmatory integral system test program being conducted at the Japanese. ROSA-V facility.
Issues identified during this meeting by the Subcommittee for discussion at the proposed ROSA meeting included:
- The detailed rationale associated with selection of the DVI line break SBLOCA as the most challenging transient event.
- Specifications and costs associated with the test facility instrumentation vis-a-vis ensuring adequate data quality.
2.
RES solicited the advice of the Subcommittee regarding the related issues of freezing the RELAP code as a prerequisite in performing a CSAU analysis and allowing error correction af ter the code has been " frozen".
- 3. The following topics were identified by RES and the Subcommittee -
in relation to the Subcommittee's upcoming overall review of Westinghouse's analytical program associated with the AP600 design certification effort:
The coupling of the T/H interactions between the RCS and containment, given the need to maintain long-term core cooling i
for an accident situation.
Validation of the model used to calculate thermal stratification.
- Details of the Core Make-up Tank tests (see item in 1 above-dealing with the expected insurge of RCS fluid prior to the arrival of steam from the pressurizer).
Examination of the scaling rationale associated with the separate effects test program H is conducting to evaluate T/H phenomena associated with the primary residual heat removal system.
Investigation of the adequacy of the instrumentation associated with the H ADS and CMT tests.
4.
The Subcommittee requested a
copy of the following documentation:
An INEL proprietary letter report that discusses.the operating experience of the Humboldt Bay and Dodewaard (Netherlands) reactors relative to the thermal hydraulic design parameters for the SBWR.
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T/H Phen. Sub. Mtg.
14 March 4-5, 1993
- The scaling report being conducted ~for the ROSA-V test facility (to be available in - one month's time).
t
- A " Scoping Analysis Report" issued in September, 1992 that supported selection of the SB LOCA for the CSAU analysis (scenario selection) associated with the use of RELAP5 for AP600 analyses.
ORNL/NRC Letter Report 92-20 that summarizes the comments received from the RES Peer Review of Volume IV (Models and Correlations) of the RELAPS/ MOD 3 (R/5) Code Manual.
- The report that summarizes the comments received from RES's
-.i Peer Review of Volume VI (Numerics) of the R/5 Code Manual (to be available in June, 1993), and a copy of' Volume VI itself when it is issued (September, 1993).
An EG&G report that details the use of.a second-order accurate Godunov method to solve the advective transport equation for tracking of boron distribution.
[ Note: A copy of this report was provided to P. Boehnert for distribution.to the Subcommittee.)
BACKGROUND MATERIAL PROVIDED TO THE SUBCOMMrrrEM FOR THIS MEETING:
1.
"RELAPS/ MOD 3 Code Manual" : Volume I - Code Structure, System Models, and Solution Methods (Draft);
Volume III - Developmental Assessment Problems (Draft),
- and, Volume IV Models and Correlations (Draft), June 1990 2.
NUREG/CR-5535, Vol.
4:
"RELAPS/ MOD 3 Code Manual Users Guidelines", January, 1992 3.
Memorandum, G.
- Rhee, NRC-RES, to P.
Boehnert, ACRS, dated December 23, 1992, transmitting ROSA Facility Modification Design Requirements Additional details on this meeting can be - obtained from a transcript of this meeting located in the NRC Public Document Room, 2120 L St. N.W., Washington, DC 20037.
This transcript can also be purchased from Ann Riley & Assoc.,
Ltd.,
1612 K.
St.
N.W.,
Washington, DC, (202) 293-3950
D.
AP600 RESEARCH PROGRAM 4~ ~
DEVELOP CSAU-STYLE APPROACH FOR CODE IMPROVEMENT AND ASSESSMENT.
PERFORM PLANT CALCULATIONS FOR DBA USING RELAP5/CONTAIN CODE.
PERFORM LBLOCA ANALYSES USING TRAC-PF1.
1 RUN ROSA /AP600 FULL-HEIGHT FULL-PR$5SURE TEST PROGRAM FOR SBLOCA, SGTR, AND MSLB.
IDENTIFY IMPORTANT MODELING REQUIREMENTS FOR AP600 AND INSTALL IN RELAP5.
ASSESS RELAPS AGAINST TEST DATA SEPARATE EFFECTS:
W:
PRHR W:
CMT W:
PCCS (CONTAIN)
INTEGRAL EFFECTS:
W:
SPES W:
OSU NRC:
ROSA-V
^
pu.T
E.
SBWR RESEARCH PROGRAM PERFORM PLANT CALCULATIONS FOR DBA.
CHOOSE CONTRACTOR FOR SCALED LOW-PRESSURE LOOP; TEST GDCS SYSTEM WITH CORRECT SBWR GEOMETRY; COMPARE WITH PREVIOUS GIST TESTS.
PROVID5 CAPABILITY TO LINK CONTAINMENT (CONTAIN) AND VESSEL (RELAP) CALCULATIONS.
IDENTIFY IMPORTANT MODELING REQUIREMENTS FOR SBWR AND INSTALL IN CODE (RELAPS).
IMPROVE RAMONA-4 CODE AND INSTALL SBWR MODELING TO INVESTIGATE SBWR STABILITY.
ASSESS CODES AGAINST TEST DATA.
SEPARATE EFFECTS:
GE:
MIT/ BERKELEY CONDENSATION GE:
PANTHERS (IC, PCCS)
INTEGRAL EFFECTS:
GE:
GIRAFFE (RPV, IC, PCCS, S/P, DRY-WELL)
GE:
GIST (RPV, GDCS, S/P, DRY-WELL)
NRC:
SCALED LOW-PRESSURE LOOP (RPV, GDCS, S/P, DRY-WELL, IC, PCCS)
GE:
PANDA (IC, PCCS, S/P, DRY-WELL)
/'"*i
J S
6 I
N _1 1
set 1JrO4Nr5 218. sect NPpl C powet Scenerm W NO C00C CAP. 6 l'
1A r
Desene Safety Evolueteen Criteria E stettise I
Assessm ent +HRene Paenemonal Maerts y
4 teentsfy Code
- p Requivemente I 4A New No Selector Esportment uodify Code YES 1'
U BB l'
SA 3C Perform New Emperementel
-Nosaltsellen Defsne NPP E neersmenta Data Base si rwwr 2 AN sE U 8D U
eP MO N &
Perterm Deve6ee er 1t Devotee er PARA &CTDt3 Assessment h Modify Emp.
M Mod #fy Ptent -
Calculations Docks Deces v ea I
r vedeie De. monici,e,,pe___ P e rte,,r,m i
Pie Aneive.s lI Are it.e Scene,.ee. nd i,,.\\ NO
~
- /
eds. the input,
- /
PIRT. Date Bese e
Do. m.nionen Ase. eiey YES l'
_ mas.e,c,,7 N<=sm.er, N
A
.co c 4
=;',y c
10 a(Isrtasvrv yw e
-- -re,
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'I CALCLLATOS j
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,e of A merie.,m CSAU Application to ALWRs 1
O) t, F/4. 3a
ALWR CODE DEVELOPMENT / ASSESSMENT STEPS 2)
HPP SELECTION - PUT FIRST TO AVOID ITERATION.
1)
SCENARIO SELECTION - SBLOCA WILL BE THE FOCUS OF BOTH DESIGNS.
OTHER SCENARIOS WILL BE CONSIDERED DURING ITERATIONS.
lA) DEFINE SAFETY EVALUATION CRITERIA - CONSULT CHAPTER 15 AND PRE CSAU EXPERIENCE.
3)
PHENOMENA RANKING - EXPERT ADVICE WILL AUGMENT THIS STEP.
4)
IDENTIFY CODE REQUIREMENTS - EXPERT ADVICE WILL AUGMENT THIS ST 4A) SELECT OR MODIFY CODE.
7)
ESTABLISH ASSESSMENT MATRIX - CURRENT FOCUS ON NEW COMPONENTS, SYSTEMS, AND UNIQUE SYSTEM INTERACTIONS.
LITTLE CURRENT DATA EXISTS.
8)
ASSESSMENT - ORIGINAL CSAU FOCUSSED ON DEFINING NPP NODALIZATIO COMPARISON OF CALCULATIONS TO EXISTING DATA. CURRENT PROCESS IS GREATLY EXPANDED TO INCLUDE DEVELOPMENT OF DATA BASE AND ALL ASSESSMENT AND PLANT TYP?CALITY ANALYSES.
5)
UPDATE DOCtMENTATION - DOCUMENTATION SHOULD BE UPDATED AT EACH STEP.
l THIS STEP ASSURES THAT ADEQUATE DOCUMENTATION EXISTS PRIOR TO UNCERTAINTY EVALUATION.
6)
DECISION NODE - IS INFORMATION GOOD EN0 UGH TO DO UNCERTAINTY ANALYSIS FOR PARTICULAR TRANSIENT CHOSEN 7 9-14)
REMAINING STEPS - BIAS, SENSITIVITY, AND UNCERTAINTY t MLYSIS ARE RELATIVELY UNCHANGED.
ps
RELAP PEER REVIEW
~
VOLUME 1 CODE STRUCTURE, MODELS, SOLUTION METHODS VOLUME 2 PROGRAMMERS GUIDE
/ VOLUME 3 DEVELOPMENTAL ASSESSMENT JUNE 1990
[ VOLUME 4 MODELS AND CORRELATIONS
/
REVIEWED BY:
PETER GRIFFITH, MIT
/
-3 YASSIN HASSAN, TEXAS A&M
~
GERALD LELLOUCHE, S LEVY MARINO DI MARZ0, MARYLAND
// v p g
MARK WENDEL, ORNL REFERENCE ORNL/NRC/LTR-92-20 sf#
VOLUME 5 USER GUIDELINES JANUARY 1992 BEING REVIEWED BY CSNI PWG2 - TO BE DISCUSSED AT NEXT MEETING IN JUNE, 1993 V0L ME 6 NUMERI Q 1992 REVIEWED BY:
MICHAEL 00 STER, NC STATE JOHN MAHAFFEY, PENN STATE PAUL WILLIAMS, ORNL DUE JUNE, 1993 REVIEW 0F VOLUMES 3 AND 4 FOCUSED ON THE DOCUMENTATION AND NOT THE DEVELOPMENTAL ASSESSMENT OR THE CODE ITSELF lF/As]
k CSAU Application to ALWRs 1
Steps 1 Through.8 c
2 Select NPP
> l Select Scenarios}4-- -
lI 1A Define, Safety '
Evaluation Critoria 7
Establish i
3 Assessment 4--lRank Phenomenal Matrix y
4 i
identify Code 3r Requirements
^
Ne>w T
4A NO Selector Experiment Modify Code YES II 8A II 88
'II 8C j
Perform New Experimental Define NPP m
Experiments Data Base Nodalization
-l 8E I I 80 II Perform Develop or-1r Develop r I
Assessment c Modify Exp. <'O Modify P'
-! Calculations Decks ~
Deck II 8G 5
Perform
> Update Documentation 4 Plant Analyses lf Are the Code, the input, PIRT, Data Base, NO Scenarios, and the Documentation Adequate?
YES II CCNM W79
AP600 CSAU Step 4 Model improvements in Process for RELAPS
- Thermal stratification e Boron transport
/
e Containment behavior (CONTAIN link) g/
e Condensation with noncondensable
N e Level tracking
'\\
e Sparger condensation
's e Spherical accumulators (Accelerated computation Feb.1991 Applicability of R5 for AP600 Analyses Feb.1991 AP600 SBLOCA Scoping Calculations Sept.1991 R5 Enhancement Needs June 1992 FIN L2537 m.....
i:
. EXPERIMENTAL DAT STATUS
+
SYSTEM PIIENOMENA OF CONCERN-MOlini TO BE ASSESSED TESTS PRESSURE f
~
( p f.
H Literature Required (SET)
(SET)
SET IET PCCS L
G TE COOLING
[e ch/jg,[/d
- INTERNAL HEAT
- CONDENSATION WITH 90 e
IDW TRANSFER NONCONDENSABLES
,y
- EXTERNAL HEAT
- EVAPORATIONWITH eO e
LOW 7
TRANSFER NONCONDENSABLES f) /
/ /"I((fgL c
PRIIR RESIDUAL HEAT REMOVAL T
<[d #
CAPABILITY
//
- WIT 11 COVERED TUBES
- TUBE BUNDLE HEAT e
e O' HIGH
/c JJ TRANSFER AND TWO-DIMENSIONAL FLOW IN A TANK g
- WIni PARTIALLY-
- LIQUID / VAPOR e
e HIGH COVERED TUBES PARTITION OF HEAT TRANSFER CMT CMT DRAINING RATE
- EFFECTS OF
- CONDENSATION O
e O
HIGH CONDENSATION
,c
/
- TIIERMALTf.
, N )
s
- TEMPERATURE PROFILE O
O HIGH TIFICATION)L
- LIQUID CARRYOVER
- Ll ID ENIKAINMENT O
e O
HIGH FROM COLD LEGS.
e DATA AVAILABLENOW 8
- HIGH PRESSURE - UNTIL 4T11 i
O DATA NOT AVAILABMYET 4- -
STAGE ADS
~f gp LOW PRESSURE-LONG-TERM (W/Ifi'/x'/ urn,eg/
j, ia COOuNO
[ C (', nw !
~
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m sess _ 1 m.e e>
e p..,w
t N
EXPERIMENTAL DATA STATUS l
SYSTEM PHENOMENA OF CONCERN MODELTO BE TESTS PRESSURE g4 d,_ len;, f p;
/
ASSGGSED _ $
}y Literature Required
]_ /, /
W
- v,.-/ /. /,-
f;,f /.,-
f_ z/
(SET)
(SET)
SET IET ADS SPARGER DISCHARGE FLOW REGIME /
O e
HIGH/ LOW INTO IRWST INTERFACIAL HEAT TRANSFER DEPRESSURIZATION DUE CRITICAL FLOW AT O
O LOW TO DISCHARGE OF 4TH LOW PRESSURES STAGE ADS
_L,o
_ /C.,
CONTAINMENr/ CONDENSATEDRAINING CONDENSATE O
O LOW SUMP INTO SUMP TRACKING PRIMARY REFILL LIQUID LEVEL O
O LOW THROUGH BREAK AND TRACKING SUMP CHECK VALVES REACTIVITY BORON TRANSPORT FROM BORON TRACKING O
HIGH CONIROL CMTS AND ACCUMS CORE BORON REACTIVTTY, POINT KINETICS O
HIGH PRESSURE WAVES, COLD WATERINSERTION ECC INJECTION FLOW DISTRIBUTION, INTERFACIAL DRAC 9
O HIGH/ LOW INTO DOWNCOMERLOW PATTERNS, CCFL, INTERFACIAL HEATTRANSFER HEATTRANSFER,
'IHERMAL STRATIFICA-TION & MIXING b
l i
ASSESSMENTTABLE Page 2 of 4
EXPERIMENTAL DATA STATUS SYSTEM PHENOMENA OFCONCERN MODELTO BE TESTS PRESSURE ASSESSED
_W Literature Required GET)
OET)
SET IET SAFETY HIGH PRESSURE INTEGRAL I?REGRATED CODE O
O HIGH SYSTEM SYSTEM PERFORMANCE PERFORMANCE j
INTERACTIONS (SBLOCA, SLB, SGTR, AND BEYOND DBA EVENTS f
SUCH AS MULTIPLE FAILURE SCENARIOS) l l
- INTERACTION OF O
SAFETY AND NON.
SAFETY SYSTEMS (CVCS AFFECTING CMT)
{
- CMTRECIRCULATION
- INTERACTION OFCMT AND PRESSURIZER LEVELS (MANOMETER EFFECT)
- ADSIRWSTTIMING/ DELAYS
- ACCUMULA'IDR NITROGEN DISCHARGE AFFECTING SYSTEM DEPRESSURIZATION
- CMTRECIRCULATION
- ASYMME'IRICBEIIAVIOR
- ECCL FLOW RATE & BYPASS
- PRHRIRWSTINERACTION
%i
- PRHR NA'IURAL Qk CIRCULATION l
- DOWNCOMER 2D EFFECTS.
ASSESSMENTTABLE Page 3 of 4 1
r.
EXPERIMENTAL DATA STATUS SYSTEM PIIENOMENA OF CONCERN P10 DEL 1D BE TESTS PRESSURE ASSESSED M(
Literature Requirtxi (SET)
(SET)
SET IET SAFETY LOW PRESSUREINTEGRAL INTEGRA~mD CODE O
LOW SYSTEM SYSTEM PERFORMANCE PERFORMANCE INTERACTIONS. 4TH STAGE ADS AFFECTING IRWST FLOW
- ADS DISCHARGE AFFECTING IRWST
- SMALL, GRAVITY DRIVEN FLOWS
- INTERACTION OF SAFETY AND NON-SAFETY SYSTEMS (NORMAL RHR AFFECTING IRWST)
I Q Q,\\
r ASSESSMENTTABLE Page 4 of 4 1
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Downcomer Nodalization
. Improvement:
h j. Calculation of downcomer condensation in the AP600 in which cool liquid flows into a downcomer filled with hot steam.
- Observation:
Unrealistic phenomena calculated in the AP600
,/ downcomer; attributed to incorrect condensation.
- Status:
Subsequent to identification of improvement, user nodalization studies led to a nodalization scheme that eliminated the calculation of unrealistic phenomena.
Improvement in this area is not planned currently because of higher priority tasks.
j m
ans+mmas
ADS and Sparger Condensation Improvement:
Condensation modeling of steam flow through the AP600 ADS valves and SBWR safety / relief valves and release through the g
spargers into the IRWST and suppression pool, respectively.
Observation:
Plausible condensation phenomena is being calculated in the IRWST. However, the behavior is known to be influenced by node size and the optimum noding is not yet established.
dtatus:
A literature search is underway (with some success) to locate
,{
applicable models and correlations. The selection process will be l
development and comparison with data. based on the ranges of e 3
mnm h
O
F ADS and Sparger Condensation
~
(cont'd)
.. Status (contd):
- q Candidate models and correlations will be put into a test version
) of RELA.P5/ MOD 3 for purposes of comparing calculations with jI data. These comparisons will be the basis for assessing code t
performance for steam condensation in a liquid pool. F,nal-i selection will be limited to no more than two models/ correlations.
s g
O
Steam Separator Improvement:
A more mechanistic steam separator model to replace the idealized j model currently in the code.
. Observation:
) The current model (for PWR SG separators) is not mechanistic
/ and does not represent SBWR separator performance.
. Status:
-The mechanistic model of the GE centrifugal separator, which was
,j)'[
developed for the TRAC-BWR code, has been recommended and U
4 approved for placement in RELAPS/ MOD 3. Also, the simple steam dryer model, developed for TRAC-BWR, will be placed in RELAP5/ MOD 3.
< The current separator model is considered adequate for PWRsg for_ steam _line break endas. For these conditions, the PWR separator g
model developed at MIT is recommended to be added as an option to the current separator model.
1 These improvements are scheduled for FY-93 funding.
N as*wman L5'9,;y,f$ e/b/
k c'
?
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Spherical Accumulator
. Improvement:
s Extend code capability to include the unique modeling requirements
[{ for spherical accumulator tanks.
. Observation:
The momentum equation and the heat and mass transfer correlations must be modified to use the volume, flow area, and surface area of a spherical tank geometry (which are dependent on a variable tank cross-sectional area).
. Status:
[ This improvement has been added to the code. Included are:
a.
An input option to define cylindrical or spherical geometry.
b.
A function to calculate volume and flow area for a spherical tank.
-c.
A generalization of the acceleration terms in the fluid momentum 1
equation to handle a tank of variable cross-section.
d.
Heat and mass transfer correlations for a spherical tank.
m s + o m eo7 m
Computational improvements for Long Transients improvement:
a Reduce the run time of the code sufficiently to allow calculation of long transients of up to 3-day duration.
- Observation:
Run time reduction of at least a factor of ten is desired to make 3-day transient calculations feasibls.
- Status:
Interest in code run time reduction has been expressed by the NRC, Bettis Atomic Power Laboratory, and Westinghouse Savannah River Company (WSRC). A proposal has been prepared to reduce the code run time by an estimated factor of ten.
The proposal is based on improvements in the areas of:
a.
Time step advancement b.
Solution efficiency c.
Parallel processing s>,
?
Computational Improvements for Long Transients (cont'd)
. Status (contd):
,_ Sponsor objectives:
NRC Capability of long (3 days) calculation of ALWR transients.
Bettis Capability of using current and future generation computer structure (parallel processing) in conjunction with a faster running code with 3D graphics display in an input preprocessor and in an,mproved NPA.
i
/
WSRC Capability of RELAP5/ MOD 3 to drive reactor simulators p-c' in real time for operator training.
c0054n42SG409 w
k
k 4.
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- Status (contd):
Specific improvements are proposed as follows:
~
Time step advancement 1.
Increased implicitness Objective: run a.t increased
-to improve robustness of time steps.
the code.-
2.
Time step control function:
i a.
time step size b.
automate degree of implicitness o
Solution efficiency 1.
Domain decomposition Addition of-new direct solvers 2.
Addition of iterative solver (use(user options) 3.
r option) 1 Parallel processing 1.
Addition of parallel processing capability a
for any number of processors.
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+ = Measured and Calculated Downcomer Coolant Flow Rates as a Function of Coolant Inventory - BETHSY Test 4.1a-TC ~ 20.0 o--a DETIISY Data p o o RELAP Calculation 10.0 Data Uncertainty ~ 10.4 kg/s I i j,e 4y 12.0 - / j [ v e o ,.o-- o.0 . \\ A 'f '4.0 N . S 0, ,o, o,o 100.0 90.0 00.0 -70.0 60.0 -50.0 40.0 30.0 N % Primary ' Mass inventory-Q1.@
l r ~~~ N Secondary Simulated} ,/ l Tube Sheet Cold Side Hot Side y SCHEMATIC DESCRIPTION OF EXPERIMENTAL SIMULATION OF THE STEAM GENERATOR TUBE RUPTURE l & f& P v w d i
~ = NODALIZATION OF THE:AP600 AUTOMATIC DEPRESSURIZATION SYSTEM (ADS) t r Oj Currently, there is insufficient data to construct a representative. model. I O /The approach to nodalization will be to limit UD to 8 in order to accommodate line losses and form losses in calculating back-pressure, choking, and delta-P.'s. 1 Ds 7lj e L 1 x I d _____.___.-_2.__mm____.___._._.u__._____.______m_.__.,__.__a____m__ 2-- -- + w n e . = v-r- w
NODALIZATION OF THE AP600 DELTA-75 STEAM GENERATOR A e,8 see i ses2 see sxH s,s 5 580 0 There are no significant design differences ps%, y between this U-tube SG and those previously a s-1 modeled which call for deviation from standard i s,o R,,, " SG modeling practices. "'"Os ,,oQ f ] iii_ i O Since the tubes are about 12 foot longer than l_l4 _L y those in a Model F SG, four more nodes are "7 -P" 4 used to model them. l- ~ ,i s O The inlet and oulet plena are each modeled as a single pipe volume because the plena are virtually the same as in previously modeled SGs. No new phenomena are anticipated in the outlet-plenum (due to the two pump y connnections) that would require deviation from standard modeling practices. x (Sk e 4 m
The RELAP5 Branch Component is used to. model the steam generator outlet plenum: ~ j2 j1 v3 j3 Sv2 The volume velocity used in the momentum flux term (1/2 ap Sx )in the momentum equation is given by: V = 1/2Vv,in + 1/2Vv,out y 3 3 where Vv,, in = Vj (apvA)j2+ (apvA)j3 N _y 1' -(ExpA)v, out w ki 9,/.
.---.-_i--..---.--...a---..-----..,---.--___-.._----.-__.-_.-------m
.u ..s + n, .s m.u. ,.,w w w > en,~-- r--,,-ww- +-,r* a- -s, r m
NODALIZATION OF THE. AP600 PRESSURIZER o The pressurizer nodalization conforms to est " = ,os standard nodalization schemes (i.e., Surry), g,_, g gL which are predicated upon tracking pressurizer pressure and level. t_ O Nodalization sensitivity studies are needed to N quantify mixture levei_ tracking. S i 4: - mmlm__ l. m_m__m_m_._____...:- _ _.. _ __ _ ' _ _ _ _. _ _ _ ~
e 4 NODALIZATION OF THE AP600 DOWNCOMER cced leg 2e to4d leg t o 80 105 2 0, O The downcomer nodalization is such that the e m l~* "I~ 2 ~ code can predict the following): 102 106 ' 1[ 30 - CMT recirculation from the downcomer (see - ~ >- - ~ '- related diagram) .c., - temperature profile around the downcomer Q during ECC injection (colder below the DVI ,5., ,g., ,g, nozzles) i ,,0 cp m ,,0 i ,0,., ,0,-, ,0,., - boron transport in the downcomer 1 ,0,4. ,0 - 0,4 10,-S ** 102-5 tot, 10s-$ +-107 5 105,"* 102 4 101 4 10& s 'g-4 07-6 105-T"* 102-F 101-7 108-7 N07 7 103 8** 102 4 101 3 10&g N07 8 = tk
~ INSTRUMENTATION i 220.NEW CHANNELS CMT ABSOLUTE PRESSURE 1 X2 DP 5 FLUID TEMPERATURE 24 WALL TEMPERATURE 13 PAIRS PRZR PBL DP 2 i X2 FLUID TEMPERATURE 3 WALL TEMPERATURE 1 FLOW 1 CL PBL ABSOLUTE PRESSURE 1 X2 DP 3 FLUID TEMPERATURE 3 y WALL TEMPERATURE 1 FLOW 1 r-DENSITOMETER 1 CMT HEADERS DP 1 X2 FLUID TEMPERATURE 1 CMT DISCHARGE DP 1 X2 FLUID TEMPERATURE 2 FLOW 1 ACCUMULATOR AND ABSOLUTE PRESSURE 1 (AS INSTALLED) DISCHARGE LINE DP 1 (AS INSTALLED) X2 FLUID TEMPERATURE 3 (AS INSTALLED) NITROGEN 1 WALL-TEMPERATURE 1 FLOW 1 (AS INSTALLED) j IRWST DISCHARGE-DP 1 FLUID TEMPERATURE 1 FLOW 1 19 ; 5 fM h
~ INSTRUMENTATION (CONT'D) DVI LINE DP 1 X2 FLUID TEMPERATURE 1 FLOW 1 ] PRHR DP 5 FLUID TEMPERATURE 11 FLOW 1 WALL TEMPERATURE 7 IRWST DP 2 FLUID TEMPERATURE 11 ADS 1, 2. 3 ABSOLUTE PRESSURE 1 DP-2 FLUID TEMPERATURE 2 WALL TEMPERATURE 1 r-DENSITOMETER 1 ADS 4 DP 3 X2 CATCH TANK FLUID TEMPERATURE 2 PRESSURIZER ABSOLUTE PRESSURE 2 (AS INSTALLED) DP 9 FLUID TEMPERATURE 6 WALL TEMPERATURE 6 PRZR SURGE LINE ABSOLUTE PRESSURE 1 X2 DP 2 FLUID TEMPERATURE 1 WALL TEMPERATURE 1 r-DENSITOMETER 1 i LOOP SEAL DP 2 X2 FLUID TEMPERATURE 1 WALL TEMPERATURE 1 FLOW 1 (AS INSTALLED) //.3/f
^ FACILIT!' CHARACTERIZATION 1. CMT DRAIN / RECIRCULATION TESTS (VIA PRESSURIZER AND. COLD LEG PRESSURE BALANCE LINES) 2. ACCUMULATOR BLOWDOWN 3. IRWST INJECTION (O PSIG) f PRESSURIZER DRAIN 5. HEAT LOSS CHARACTERIZATION ghai
- 6. -
PRHR TEST. L 7. ADS -STAGE 1 BLOWDOWN (FROM 1000- PSI) ADS STAGE 1+2 BLOWDOWN (FROM 700 PSI)
- 9. _ ADS-STAGE 1+2+3 BLOWDOWN (FROM 400 PSI)
- 10. ADS-SINGLE STAGE 4 BLOWDOWN (FROM 100 PSI)
M No 3,cep' a,e fm,Av.lakn' Yl ,,,j ue Ay g) %8 a
TEST MATRIX 1. N0 BREAK, INADVERTENT ADS STAGE 1 VALVE OPENING, SINGLE 4TH STAGE FAILURE 2 1/2-INCH BREAK 3. 1-INCH COLD LEG BREAK 4. 1-INCH COLD LEG BREAK CVCS, NRHR SFW ON 5. 2-INCH COLD LEG BREAK 6. 4-INCH COLD LEG BREAK 7. DEGB DIRECT VESSEL INJECTION LINE 8. 2-INCH COLD LEG PRESSURE BALANCE LINE BREAK i 9. DEGB COLD LEG PRESSURE BALANCE LINE BREAK
- 10. ONE SGTR
- 11. THREE SGTR j
- 12. MAIN STEAM LINE BREAK
? THE INTEGRAL SBWR-FACILITY-SHOULD HAVE VESSEL-WITH ELECTRICALLY -HEATED __ CORE CONTAINMENT CONSISTING OF DRYWELL.AND WETWELL I GRAVITY-DRIVEN COOLING SYSTEM-(GDCS) PASSIVE CONTAINMENT COOLING SYSTEM (PCCS) ISOLATION -CONDENSER SYSTEM (ICS) VALVES AND PIPING u INSTRUMENTATION AND CONTROLS RELEVANT NON-SAFETY SYSTEMS (FOR ASSESSING INTERACTIONS WITH SAFETY SYSTEMS 1 i I fn.sg;.! 7-
~ IMPORTANT ISSUES 1. VESSEL INVENTORY GDCS PERFORMANCE EVALUATION DRAINING CHARACTERISTICS OF GDCS POOLS GDCS LINE BREAK OR VALVE FAILURE AUTOMATIC DEPRESSURIZATION SYSTEM (ADS) VENTING CAPABILITY ABILITY TO MAINTAIN SAFETY INJECTION UNDER SMALL PRESSURE DIFFERENCES DECAY HEAT REMOVAL UNDER NATURAL CIRCULATION CONDITION AT. LOW PRESSURES 2. CONTAINMENT INTEGRITY PCCS PERFORMANCE EVALUATION PERFORMANCE DEGRADATION DUE TO NON-CONDENSIBLES PASSIVE VENTING 0F NON-CONDENSIBLES 3. SYSTEM INTERACTIONS INTERACTION BETWEEN GDCS AND NON-SAFETY CONTROL R0D DRIVE (CRD) WATER INJECTION INTO VESSEL INTERACTION BETWEEN GDCS AND NON-SAFETY REACTOR WATER CLEANUP AND SHUTDOWN COOLING SYSTEM INTERACTION BETWEEN PCCS AND NON-SAFETY DRYWELL SPRAY (f W. h .}}