Development and Validation of a Three-Dimensional Diffusion Code Based on a High Order Nodal Expansion Method for Hexagonal- Geometry

Table 1

HNHEX results for whole core 3D SNR benchmark in hexagonal-z geometry.

Code	Number of axial planes		error; (pcm)	(%)	(%)	(%)	(%)	(%)	CPU time (sec)
DIF	—	1.00989	—	—	—	—	—	—	—
HNHEX	8	1.01143	154	0.087	0.071	0.74	0.25	1.52	24.3
HNHEX	8	1.01056	67	0.075	0.061	0.51	0.23	0.83	27.1
HNHEX	18	1.01036	47	0.072	0.06	0.49	0.21	0.8	60.1
DIF3D Nodal	8	1.01150	161	−0.17	0.23	0.95	−0.30	−0.6	86.4
DIF3D Nodal	18	1.01125	136	−0.18	0.22	0.96	−0.11	−0.44	230.4
DIF3D(6)	36	1.01280	291	−0.27	0.42	0.47	−0.60	−1.72	576.0
DIF3D(24)	36	1.01118	129	−0.04	0.13	0.05	−0.64	−0.64	2304.0
AFEN	8	1.01334	345	0.24	0.05	−1.46	−0.81	−2.11	3207.6
AFEN	16	1.01134	145	0.08	−0.05	−1.29	−0.41	−0.92	7160.4

Reference.
Applying flat approximation for partially integrated axial leakage and quadratic approximation for one-dimensional axial spatially flux.
Applying quadratic approximation for partially integrated axial leakage and four-order approximation for one-dimensional axial spatially flux.