The Design, Construction, and Preliminary Experiment of China's ADS Subcritical Experimental Assembly Venus-1

The paper presents the design objectives and structure of China's accelerator-driven subcritical system subcritical assembly Venus-1. The core of Venus-1 is a coupled core with a fast neutron zone and a thermal neutron zone. The fast neutron zone is at the center of the core and is formed by natural uranium fuel. A fast neutron spectrum field can be produced in the fast neutron zone and used for transmutation. The thermal neutron zone surrounds the fast neutron zone and is formed by low-enriched uranium fuel; it is a fission zone. Venus-1 is driven by an Am-Be or other steady neutron source (²⁵²Cf, D-D reaction or D-T reaction) to research the effect of an external neutron source with different energies on it or is driven by a D-T pulsed neutron source through the China Institute of Atomic Energy pulsed neutron generator to research the dynamic characteristic. On July 18, 2005, the first fuel element was loaded into the Venus-1 subcritical assembly, and some preliminary experiments on subcritical and neutron distribution have been performed. The final load has been determined by preliminary experiments on Venus-1. The relative neutron importance of the external source, the relative distribution of the thermal neutron flux in the fast neutron zone, and the variation of the neutron count with the addition of natural uranium fuel also have been determined by preliminary experiments on Venus-1.