Annex 1

Reference Systems addressed within the CRP

Annex 2

Phenomena associated with natural circulation

The following lists the phenomena associated with Natural Circulation, and identifies the groups, and the group coordinators, that are collaborating to prepare descriptions of the status of codes and experiments. For the various phenomena, coordinators have been identified to work with other CRP participants in their group to prepare descriptions (roughly 25 – 30 pages for each phenomena) assimilating the status of experimental data and code assessments for each phenomenon.

These descriptions can reference more detailed reports from the involved participating institutes. In this regard, participants are encouraged to publish their work in journals and conference proceedings.

Annex 3

Integrated Research Plan

This Integrated Research Plan documents the results of the 2^nd Research Coordination Meeting on the CRP on Natural Circulation Phenomena, Modelling, and Reliability of Passive Systems that Utilize Natural Circulation held 27 August-2 September, 2005. The following Plan was agreed upon:

1. Establish the State-of-the-Art on Natural Circulation

• Action: IAEA – Publish TECDOC (11.2005)

2. Identify and Describe Reference Systems

• Action: IAEA and PSI – draft introduction for the report
• Action: AECL & PSI – examine possibility of describing NC passive systems for super-critical reactor concepts
• Action: JAEA – check if information can be supplied for SSBWR description
• Action: Purdue – provide ESBWR description when appropriate
• Action: OSU to arrange write-up for IRIS
• Action: OSU – remove experimental data and code calculations from system descriptions
• Action: OSU – provide introductory table for each system description (Basic operating data and list of passive systems for (a) core heat removal and (b) containment heat removal) and provide to CSIs for them to review
• Action: OSU – provide example section on “integrated passive system response to accident scenario addressing accident mitigation sequence / philosophy”; send to CSIs for them, if possible, to add a similar section to their system descriptions

3. Identification and characterization of phenomena (identification of related phenomena; experimental data base, and; code capabilities)

• FZR is coordinator for phenomenon 1, working with other members of the group
• BARC is coordinator for phenomenon 2, working with other members of group
• Univ. of Valencia is coordinator for phenomenon 3, working with other members of group
• Purdue is coordinator for phenomenon 4,working with other members of group
• BARC is coordinator for phenomenon 5 (assimilating results from TECDOC from previous CRP; and from NC TECDOC)
• Univ. of Pisa is coordinator for phenomenon 6, working with other members of group
• Univ. of Idaho is coordinator for phenomenon 7, working with other group members
• Action: PSI is coordinator for phenomenon 8, working with other members of the group
• Idaho State is coordinator for phenomenon 9, working with OSU and other members of the group
• OSU is coordinator for phenomenon 13 working with Purdue, PSI and other members of the group
• FZR is coordinator for phenomenon 14 (= “stratification and mixing of boron”) working with other members of the group
• Action: By Nov 15 each coordinator, working with the members of his group, will send a definition (0.5 to 1 page) of the phenomenon for which they are responsible, to IAEA.
• Action: IAEA – arrange small Consultancy Meeting to develop clear concise definitions of natural circulation and the phenomena that influence NC – in order to clearly specify the scope of the documents to be prepared by each phenomena coordinator addressing the status of experiments, models and codes.
• Action (all): Determine whether additional results of investigations of phenomena, currently restricted, can be provided – especially for “behaviour in large pools of liquid”
• Action: Each coordinator for a phenomenon, working with his group, will begin to prepare a document on the status of experiments and codes (write-up of 25-30 pages for each phenomenon - draft write-ups on phenomena by coordinators are to be presented at next RCM)
  
  
• note: for each phenomenon, the coordinator, working with his group, will assimilate the status of experiments, data and code assessment – for that phenomenon
• note: BWR in-stability has been addressed in other international cooperation. As it is a large subject area, it will therefore be addressed in this CRP in a summary way using presentations made at the 1st RCM, and possibly through a presentation on the work of Central Research Institute of the Electric Power Industry (CRIEPI, Japan) at the 3^rd RCM
• note: within the CRP, detailed information on test facilities and corresponding test results is being shared:
  • PANDA ISP-42 test series
  • Idaho State University’s work on Condensation Induced Water Hammer (CIWH)
  • OSU tests with MASLWR on primary system flow stability in integral PWR designs

4. Application to Design and Safety (Coupling of the phenomena and reference systems)

Analyses of integral system tests:

• Within the CRP, detailed information on test facilities and corresponding test results is being shared – for example:
  • PANDA ISP-42 test series
  • OSU is establishing test plan for potential stability tests at MASLWR. Discussions were held on development of the test plan.

• Action: OSU to provide design data / description for MASLWR and initial and boundary conditions (by 30 Oct) for use in setting up pre-test calculation models (e.g. at BARC, Univ. of Pisa, and perhaps CNEA Barilochi, KAERI, and others) and making pre-test predictions by end of April to send to OSU. Organizations which may make pre-test calculations will decide by end of October, and inform IAEA and PSI
• Action: CRP participants wishing to examine the ISP 42 provided by PSI should IAEA to obtain the detailed information on the test facility, the conduct of the tests and the test results; Results of analyses by CRP participants (1 or more Phases) will be presented to 3^rd RCM.

The following presentations are planned for the 3^rd RCM:

• Integral System Tests and Analyses:
  • BARC will present integral system tests
  • JAEA will present ROSA AP-600 integral system tests
  • CNEA will present CAREM tests
  • OSU will present APEX tests (if NRC allows)
  • Purdue will present PUMA experiments and code predictions for the SBWR-1200 design
  • Organizations making pre-test predictions for the integral system stability tests at MASLWR will present them
  • OSU will present results of MASLWR integral system stability tests
  • AECL will present work on passive moderator cooling experiments and analyses

• Plant Analyses:
  - Gidropress will present analyses of WWER-640 and WWER-1000 - IVS Slovakia will possibly present analyses of WWER-440 (to be determined by 6.2006) - CNEA Barilochi will present analyses of CAREM transient – loss of heat sink, and possibly stability analysis - KAERI will present SMART transient analysis - CRIEPI will be invited to present their work on BWR instability

5. Research and Development on Reliability

PSA relevant database
• Action: JRC to provide filled in example for a sample case (by end of 2005 to IAEA)
• Action: then CSIs to examine to determine if they can prepare the information – for discussion at next RCM

Improvement of Methodology for Reliability
• Continue to introduce improvements as identified by CEA (Mr. Marques) and others

Application of reliability method
• CAREM PRHRS will be the system to be addressed with the RMPS methodology: Action: IAEA to organize small Consultancy to develop plan and to identify ranges of parameters, etc. IAEA will try to organize a Fellowship(s) for CNEA analyst (or analysts) to work at the Univ. of Pisa and at Cadarache through IAEA’s Technical Cooperation programme to examine the PRHRS reliability. Initial results potentially to be presented at 3^rd RCM.