Analysis of Physical Performance of Two-Row Hexagonal Fuel Assembly for SCWR

A new hexagonal fuel assembly（FA） design which has two rows of fuel rods between the hexagonal moderator channels is proposed for the thermal supercritical water cooled reactor（SCWR）.The two-row hexagonal fuel assembly concept is first and foremost considered for the performance of uniform moderation and sufficient moderation,and with the respect of structural performance and thermal-hydraulic performance.The physical performance of the two-row hexagonal FA with acceptable configuration is investigated.The results show clearly that a better balance between uniform moderation and sufficient moderation can be obtained in the two-row hexagonal fuel assembly.The design objective of the local power peaking factor less than 1.10 can be achieved under the condition of using the same enrichment fuel and containing no burnable poison.