Design and analysis of HYPER

KAERI (Korea Atomic Energy Research Institute) has been developing an accelerator driven transmutation system called HYPER (hybrid power extraction reactor). It is designed to transmute long-lived TRU and fission products such as Tc-99 and I-129. HYPER is a 1000 MWth system with keff = 0.98 which requires 17 mA proton beam for an operation at EOC (end of cycle). Pb-Bi is used as the coolant and target material at the same time. HYPER core has 186 ductless hexagonal fuel assemblies. The fuel blanket is divided into three TRU (transuranic elements) enrichment zones to flatten the radial power distribution. The core height of HYPER was compromised at 150 cm, and the power density was determined such that the average coolant speed could be about 1.64 m/s. The inlet and exit coolant temperatures are 340 and 490 oC, respectively, in the core. The cylindrical beam tube and spherical window is adopted as the basic window design of HYPER. We have also introduced an Lead-Bismuth eutectic injection tube to maximize the allowable proton beam current. A metallic alloy of U-TRU-Zr is considered as the HYPER fuel, in which pure lead is used as the bonding material. As a result, a large gas plenum is placed above the active core. TRU transmutation rate is 282 kg/yr. In the case of a FP transmutation, 28.0 kg of Tc-99 and 7.0 kg of I-129 are incinerated per year. The MACSIS-H (metal fuel performance analysis code for simulating the in-reactor behavior under steady-state conditions-HYPER) for an metallic fuel was developed as the steady-state performance computer code. The MATRA (multichannel analyzer for transient and steady-state in rod array) code was used to perform the thermal-hydraulic analysis of HYPER core