Development of natural circulation analysis methods for a sodium cooled fast reactor

Figures & data

Figure 1. Schematic of the SFR heat transport systems.

Figure 2. Outline of one-dimensional safety analysis model.

Figure 3. Improved reactor upper plenum analysis model.

Figure 4. Structure of three-dimensional method.

Figure 5. Schematics of plant dynamics test loop (PLANDTL).

Figure 6. One-dimensional modeling for water test analyses.

Table 1. Summary of the validation analysis cases for water tests.

No.	Transient events	Notes
1	Loss of off-site power	Reference
2		Flow coast-down time is shorter than the reference for 50 seconds.
3		Flow coast-down time is longer than the reference for 50 seconds.
4		Startup times DHRS is earlier than the reference for 100 seconds.
5		Startup times DHRS is later than the reference for 100 seconds.
6		Startup times DHRS is later than the reference for 300 seconds.
7	Sodium leakage in the secondary loop	Failure loop B
8		Failure loop A
9	Sodium leakage in the secondary side of PRACS	Reference (failure loop A)
10		Reference + one damper fails in PRACS B + DRACS forced circulation
11	Sodium leakage in the secondary side of DRACS	Reference
12		Reference + one damper fails in PRACS B
13	One pump stick in the primary loop	Failure loop A

Figure 7. Boundary conditions of one-dimensional method for loss of off-site power.

Figure 8. Simulation results of one-dimensional method for loss of off-site power.

Figure 9. Boundary conditions of one-dimensional method for one pump stick in the primary loop.

Figure 10. Simulation results of one-dimensional method for one pump stick in the primary loop.

Figure 11. One-dimensional model for sodium test analysis.

Figure 12. Boundary conditions of one-dimensional method for all system scram transition test.

Figure 13. Simulation results of one-dimensional method for all system scram transition test.

Figure 14. Three-dimensional model for water test analyses.

Figure 15. Simulation results of three-dimensional method for loss of off-site power.

Figure 16. Simulation results of three-dimensional method for loss of off-site power.

Figure 17. Simulation results of three-dimensional method for one pump stick in the primary loop.

Figure 18. Vertical section temperature distribution of RV upper plenum in one pump stick in the primary loop.

Figure 19. Three-dimensional fluid modeling for sodium test analysis.

Figure 20. Simulation results of three-dimensional method for all system scram transition test.

Figure 21. Temperature distributions in PLANDTL under natural circulation condition (at 3600 seconds after the trip).

Figure 22. Blind analysis results of one-dimensional method.

Figure 23. Blind analysis results of three-dimensional method.