Overview of USHPRR Fuel Irradiation Testing for Base Fuel Qualification

Transcription

1 Overview of USHPRR Fuel Irradiation Testing for Base Fuel Qualification February N.E. Woolstenhulme

2 Irradiation Testing As a fuel development program, nearly everything takes places within the framework of irradiation testing campaigns. Arena for developing fabrication processes Provide specimens for fresh fuel characterization, irradiation, and post irradiation examination (PIE) Overall irradiation program method, provide scientific, engineering-scale, and end-use fuel performance bases: Start small, end big Mini-Plates (MP): Length ~10 cm Full Size Plates (FSP): Lengths from ~30 cm to ~125 cm Element Tests (ET): Multiple plates in one assembly, length ~125 cm MP FSP ET 2

3 Intro Out of pile fabrication studies and Mini-Plate-1 (MP-1) irradiation downselection of the base-fuel process/product specifications MP-2 and Full-Size Plate-1 (FSP-1) campaigns populate data for qualification FSP-1 also forerunner to Element Test-1 (ET-1) driver fuel demonstration in ATR 3

4 Intro Summary of the three base fuel qualification campaigns MP-2: Irradiate larger quantities of small specimens Substantial exploration of design and environment variables Statistical replication in establishing irradiation performance FSP-1: ET-1: Irradiate moderate quantities of larger specimens Focused exploration of design and environment variables Specimens purposed to reveal the effect of plate size Small quantities of end-use fuel assemblies (e.g. driver fuel) Focused PIE data, confirmation that fuel behavior is maintained in the enduse design application 4

5 Intro MP-1 design is nearly complete, based heavily on integrating program needs into one experiment which will enable fab process downselection Presented in greater detail previously by Irina Glagolenko MP-2 design effort underway Strong focus on specimen and data statistics FSP-1 design is approaching completion Rigorous test planning, gathering data to demonstrate fuel performance criteria Careful flowdown of fuel performance and hardware requirements Meticulous design of experiment conditions and hardware 5

6 MP-2 MP-2 conceptual design recently commenced Will only irradiate the downselected fuel design Like MP-1, targeting ~100 specimens total Focused on strong statistics in fuel performance data Designed to fill in the gaps Will show fuel performance as function of burnup, power, thickness Courtesy of N. Lybeck and I. Glagolenko 6

7 FSP-1 Irradiation conditions address NRC HPRR operating envelope for qualification Full Burn (FB): At high fission rates and full burnup Highest burnup in High Power Research Reactor (HPRR) design environment Thick Meat (TM): Fuel swelling from U-Mo thickness and medium burnup Highest fuel meat thickness and burnup combination in the HPRR design environment FSP-1 also go/no-go for ET-1 insertion (ET-1 will be ATR driver fuel) Intermediate Power (IP): ~125 cm fuel length at ATR normal-cycle power and burnup Highest heat flux for ATR driver fuel at normal-cycle power 7

8 FSP-1 FSP-1 design: Combine salient aspects into one single irradiation Variety of irradiation conditions Exclusive use of 19.75% enriched specimens Made possible by the Advanced Test Reactor (ATR) North East Flux Trap (NEFT) More geometry Lobe power control Lobe power and specimen self shielding used to control power Specimen shuffling used to achieve various burnup 8

9 ET-1 ET-1 consists of 2 ATR driver fuel elements Analogous to the Oak-Ridge Research Reactor (ORR) driver fuel irradiations from historic U 3 Si 2 qualification ORR (and similar reactors) no longer available, ATR is only option Not expressly purposed as an ATR lead test assembly, normal power cycles only, not ATR high-power cycles ET-1 design full-leu (all 19 plates) in ATR driver fuel ET 9

10 DDE s Base Fuel Design Demonstration Elements (DDE s) address each of three NRCregulated HPRR s (MITR, MURR, NBSR) Not for base fuel qualification DDE s support licensing of a specific HPRR designs Focused on representing actual geometry and irradiation conditions Cannot be performed in NRC-regulated HPRR s DDE design challenge is to simulate MITR, MURR, and NBSR conditions in other test reactors (ATR and Belgian Reactor 2 (BR2)) Designs are conceptual only at this point MITR MURR NBSR 10

11 DDE-MITR DDE for Massachusetts Institute of Technology Reactor (DDE-MITR) Best option going forward is full-size element, with LEU meat, in the NEFT Will likely need shielding to control power

12 DDE-MURR DDE for University of Missouri Research Reactor (DDE- MURR) Full LEU element in Belgium Reactor 2 (BR2) 200mm H position Representative fission rates and densities achievable ATR NEFT is backup option if BR2 is not operating in 2020 s DDE-MURR MURR CD35

13 DDE-NBSR DDE for National Bureau of Standard Reactor (DDE-NBSR) Three rows of three full-size plates each in ATR center flux trap NBSR power shape (D 2 O moderated) simulated with local hafnium absorbers

14 Questions? 14