Fig. 1. Design diagram of kilopower heat pipe reactor

Fig. 2. Model framework of TAPIRS-D program

Fig. 3. Relationship curve between the reactivity value of control drum and the turning angle

Fig. 4. Diagram of radial partitioning of the core

Fig. 5. Diagram of the standard heat pipe "flat front" startup model

Fig. 6. Heat transfer model of heat pipe in normal operation (a) Heat pipe one-dimensional thermal resistance network model, (b) Improved two-dimensional thermal resistance network model

Fig. 7. Diagram of KRUSTY core layout (a) Cross-sectional view of reactor, (b) Physical view of reactor

Fig. 8. Structure diagram of self-passed arterial sodium heat pipe

Fig. 9. Diagram of KRUSTY core modeling

Fig. 10. Validation results for KRUSTY start-up condition

Fig. 11. Verification results of load reduction condition (a) Core fission power transients, (b) Fuel assembly temperature transients

Fig. 12. Validation results for load increase conditions (a) Core fission power transients, (b) Fuel assembly temperature transients

Fig. 13. Validate results of heat pipe failure accident (a) Core fission power transients, (b) Fuel assembly temperature transients

Fig. 14. Parametric response of Stirling thermoelectric conversion under negative reactivity introduction accident(a) Core fission power transients, (b) Fuel assembly temperature transients

Fig. 15. Validate results of positive reactivity introduction (a) Core fission power transients, (b) Fuel assembly temperature transients

Fig. 16. Validation results for loss of heat sink accident (a) Core fission power transients, (b) Fuel assembly temperature transients