5X5 핵연료 봉다발에서 지지격자 가공 상태에 따른 압력손실 실험

In Korea Atomic Energy Research Institute(KAERI), it holds a patent right in the U.S.A, Korea, and Japan about development of fuel rod spacer grid for high performance of Pressurized Water Reactor(PWR). We performed experiments about hydraulic characteristics of the developed spacer grid. There were 4 types of spacer grid such as Plain Spacer Grid, Chamfering/Coining, spacer grid with mixing vane without Chamfering/Coining treatment(Mixing Vane), spacer grid with spot welding and chamfering/coining treatment(Mixing Vane_SC), and spacer grid with line welding in Mixing Vane_SC(Mixing Vane_LC). We compared pressure drop coefficient and found the pressure drop coefficient is greatly affected by chamfering/coining treatment and wasn"t affected by welding procedure.