Patent Number: 044540930
Section: summary

TECHNICAL FIELD The present invention relates to a fuel assembly for a boiling water reactor, the fuel assembly comprising a plurality of vertical fuel rods which are furnished with a fuel channel device and arranged to form a plurality of groups of fuel rods, the groups along a vertical stretch constituting a predominant portion of the length of the fuel rods being each surrounded by a corresponding wall system, the wall systems being constructed in such a way as to prevent, to a substantial extent, a horizontal water transfer between the groups of fuel rods. BACKGROUND ART Fuel assemblies of the kind mentioned above are known, for example, from the U.S. Pat. No. 3,164,530 and the U.K. patent application No. 2,054,247 A. With fuel asssemblies of this kind, it is necessary to ensure that sprinkling water is evenly supplied to all groups of fuel rods in the assembly upon an emergency cooling, even if the location of the fuel assembly in relation to the nozzles of the sprinkling system results in a considerable variation from group to group of the amount of sprinkling water supplied directly from the nozzles. A fuel assembly according to the invention is particularly advantageous in such cases where a fuel assembly of the design described in the introduction, that is, a fuel assembly with a plurality of subassemblies or groups, is used in a reactor having a sprinkling system for emergency cooling of the core is constructed fuel assemblies not divided into subassemblies. DISCLOSURE OF THE INVENTION According to the invention, a fuel assembly comprises a fuel channel having a portion, located above the fuel rods, the horizontal projection of which surrounds all the fuel rods in the fuel assembly, the fuel channel portion being provided with a substantially horizontal water distribution channel extending along the inner side of the fuel channel portion, said distribution channel is arranged to receive emergency cooling water supplied to the fuel assembly from a location vertically above at least one of the fuel rod subassemblies and to supply received emergency cooling water to at least one of the other fuel rod subassemblies.