Fig. 1. Arbitrary triangular prism in (x, y)

Fig. 2. Equilateral triangular prism in (x′, y′)

Fig. 3. Mesh generation of unstructured geometry (a) Heat pipe reactor, (b) Space reactor

Fig. 4. Diagram of the radial core layout of ACMIR

Fig. 5. Diagram of mesh generation of radial core

Fig. 6. Radial power distribution of fuel assembly

Fig. 7. Raidal layout of heat pipe core

Fig. 8. Radial modeling (a) and mesh generation (b) of heat pipe core

Fig. 9. Radial power distribution of fuel assembly