摘要 |
A fuel assembly for a nuclear reactor comprising a number of fuel rods arranged in a regular fashion in a channel box which is surrounded by water gap in a reactor core. Some of fuel rods disposed at portions facing the water gap through which no control blade is inserted or drawn out, have atomic number densities of fissionable material contained in the fuel rods. The atomic number density of each of these fuel rods is made smaller than that of the fuel rod disposed in the fuel assembly at portions other than the portions referred to above. |