1 / 25

Status of He-EFIT Design Pierre Richard – J. F Pignatel – G. Rimpault

Status of He-EFIT Design Pierre Richard – J. F Pignatel – G. Rimpault. Outline. Recall of the Design Approach Main Issues Addressed since the February (Bologna) Meeting Updated Table of He-EFIT Main Characteristics

doyle
Télécharger la présentation

Status of He-EFIT Design Pierre Richard – J. F Pignatel – G. Rimpault

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Status of He-EFIT Design • Pierre Richard – J. F Pignatel – G. Rimpault

  2. Outline • Recall of the Design Approach • Main Issues Addressed since the February (Bologna) Meeting • Updated Table of He-EFIT Main Characteristics • Presentation of the current core design : Core, Spallation module, Power Conversion Cycle • DHR Approach • Conclusions – Next steps

  3. He-EFIT Design Approach 1 – Spallation module design using the outcome of the PDS-XADS Project 2 - Define the Proton Beam Intensity (for a maximum proton energy of 800 MeV), the reactor power and the Keff (assuming the potential reactivity insertions and burn up swing which have to be checked later)  3 - Design the core taking into account the design objectives (MA burning, Keff considerations,…) and the core design constraints (Fuel composition, cladding composition, pressure drops,…)---------------------------------------------------------------------------------- 4 - Define the approach for the DHR and design the DHR main components (blowers, HX,…)  5 - Design the primary system 6 - Design the Balance of Plant and Containment and implementation of the plant (cooling loops, confinment building, …) Steps 2 and 3 require iteration loops with neutronics, T/H and geometry considerations  Required some time

  4. Proton beam characteristics : Energy changed from 600 MeV to 800 MeV which is currently considered as an upper limit : over 800 MeV, the radio-toxicity increase rapidly Need for higher proton beam intensity 18-22 mA instead of 10-20 mA Plant Efficiency : First Assessment made at CEA : with Tin/Tout = 400/550 °C AMEC/NNC : incentive to increase the Tcore from 150 °C to 200 °C Decision from the Lyon meeting (03/06) : Tin/Tout = 350/550 °C Plant efficiency increased to 43.3 % Fuel Characteristics : CERCER (MgO matrix) limit temperature at nominal conditions decreased from 1860 °C to 1380 °C CERMET (Mo matrix) considered as back up solution (decision from the Cadarache meeting in June) S/A Characteristics : S/A Outer width over flats reduced from 162 mm to 137 mm : target size corresponding to 19 S/A at the center of the core Evolutions since the Bologna Meeting (1/3)

  5. Core Design : Core power decreased to 400 MWth (600 MWth before) 3 zones core with different pin diameters Peaking factors : Total peaking factor changed from 1.61 to 1.839 : iteration with neutronic calculations Adaptation to He-EFIT of the objectives defined by the “Specialist Meetings” (March-June 2006) : 42 Kg MA burnt par TWhth Flat Keff versus BU Reasonably low current requirement < 20 mA Low pressure drop < 1.0 bar Clad temperature limit < 1600°C (transient), < 1200°C (nominal) Coolant speed < 50 m/s Others : Wrapper Thickness, Number of grids, … Evolutions since the Bologna Meeting (2/3)

  6. Evolutions since the Bologna Meeting (3/3) • Cross-check with FzK and modifications of the correlations for Heat Exchange Coefficients, Core Pressure Drops and Fuel Conductivities (According to DM3 recommendations) : • Rather good agreement : • Core composition f < 0.05 % • Fuel Max Temperatures T< 20 °C • Cladding Max Temperatures T< 6 °C • Pressure drops : incoherency in the Dh calculationsbut small consequences : (P) < 0.034 bar • Safety : • Pressure drop limited to 1 bar for the core and 1.5 bar for the whole primary circuit  Provisional value to be checked by appropriate transient calculations • DHR strategy - Comparison of different two approaches : “XADS-like” approach / GCFR approach

  7. Main Characteristics of the Gas-Cooled EFIT (1/3)

  8. Main Characteristics of the Gas-Cooled EFIT (2/3)

  9. Main Characteristics of the Gas-Cooled EFIT (3/3)

  10. Current Design • A three zone core has been preliminarily studied : • Zone 1 (inner) : 45 MWth, 42 sub-assemblies • Zone 2 (intermediate) : 165 MWth, 156 sub-assemblies • Zone 3 (outer) : 191 MWth, 180 sub-assemblies • The main hypothesis and/or design objectives accounted are the following : • Core heigth : 125 cm • External width over flat : 137 mm • Fuel (fuel+matrix) fraction in the diffrent zones : 11%, 21.5 % and 35 % (for respectively zone 1, 2 and 3) • Matrix volmue fraction in the fuel pellet : 50 % • - The total form factor was assumed to be the same in the three zones (1.839) Remarks : 1 - Core pressure drops are not equilibrated (too many design constraints). They are respectively 0.84, 0.74 and 1 bar in zone 1, 2 and 3  some gagging will be necessary 2- The pellet diameter in zone 1 is rather small (2.3 mm). If this induces some problem, the number of pin rows per S/A can be reduced to 11 row per S/A.

  11. Current Design – 50 MW/m3 (1/2)

  12. Current Design – 50 MW/m3 (2/2)

  13. “Cold” Window Concept (1/2)

  14. Target central part made of a bundle of horizontal W-rods (see detail A) Dext = 266 mm Proton Beam Radial pitch He flow Target lower peripheral ring also in W (assume a porosity of 50% for He flow)) Helium Axial pitch “Cold” Window Concept (2/2)

  15. Assumptions : Keeping the indirect Supercritical CO2 cycle with re-compression CO2 remains super-critical : CO2 characteristics above the Critical Point (74 bar/32 °C). This avoids the presence of water in the compressors (badly known behaviour of the components) CEA Low Heat sink Temperature considered too restrictive : 16 °C  21 °C Parametric study on the core inlet temperature : +/- 50 °C Power Conversion Cycle – AMEC-NNC Assessment

  16. Power Conversion Cycle Main Compressor Auxiliary Compressor Turbine  43.3 %

  17. Goal : Compare different strategies : Active/Passive Guard Containement/No guard Containment Background : GCFR Approach PDS-XADS (He-cooled XADS) Decay Heat Removal - Approach

  18. Schematic of DHR system (CEA initial proposal) pool Exchanger #2 Secondary loop H2 Exchanger #1 dedicated DHR loops • 3 loops of DHR • 3 pools • 1 guard containment H1 Guard containment core

  19. DHR (CEA studies)

  20. GFR STRATEGY (CEA Approach) • For the GFR 2400MWth • -The high back-up pressure strategy (25Bar) is not kept • -for GFR the intermediate back-up pressure strategy (~5 Bar) is studied • -Back Up solution :The full depressurisation (1Bar) (still not studied)

  21. PDS-XADS Basic Reactor options: • Reactor power : 80MWth • First core: classical FBR fuel U-PuO2 (35% Pu max) • Accelerator: designed for 600MeV/6mA but can be upgraded to 800MeV/10mA • Core and Target Unit designed for 600MeV/6mA • Separated target: liquid • Primary circuit: He DHR Strategy : • No Guard Containment • Full depressurization 1 Bar • Integrated SCS (but only 2 MWth to be removed by each SCS)

  22. PDS-XADS SCS Design • Integrated SCS (Electric Power 55kW)

  23. DHR for EFIT • For He-EFIT: • The PDS-XADS solution seems better • Proton beam complexity  Guard containment not keep • If the full depressurization is chosen, a strategy must bedefined : • The blowers must work 1 to 70 Bars : Requires High Power and a complex Blower Design (or 2 systems : 1-10 bars and 10/70 bars? ) OR • Blowers can work only at low pressure :  Acton for fast depressurization System systematically used (safety)  SIMPLIFICATION of procedures • System implementation : • 3 DHR loops designed for 100 % • 2 Solutions : Loops integrated on the vessel/Ex-vessel loops

  24. Conclusions (1/2) Current Design : • A three zone core has been preliminarily studied : • Zone 1 (inner) : 45 MWth, 42 sub-assemblies • Zone 2 (intermediate) : 165 MWth, 156 sub-assemblies • Zone 3 (outer) : 191 MWth, 180 sub-assemblies • The main hypothesis and/or design objectives accounted are the following : • Core height : 125 cm • External width over flat : 137 mm • Fuel (fuel+matrix) fraction in the different zones : 11%, 21.5 % and 35 % (for respectively zone 1, 2 and 3) • Matrix volume fraction in the fuel pellet : 50 % • - The total form factor was assumed to be the same in the three zones (1.839) • DHR Approach under discussion

  25. Conclusions (2/2) Next steps : • Detailed neutronic calculations : • Neutron source behaviour by the mean of MCNPX Calculations • Core neutronics by the means of MCNPX and ERANOS calculations. • Even if the current core design is not fully defined, He-EFIT main characteristics (core power, main core dimensions)are sufficiently defined to go ahead with : • Safety Approach/DHR strategy : • Pre-sizing of the DHR loop components (AREVA ??) • CATHARE/SIM-ADS modelling (CEA/FzK ???) • Remontage (AREVA)  Dissemination of the main He-EFIT design characteristics – Iteration with the partners

More Related