US 5,513,233 A · Nuclear reactor

Abstract

Improved operability and economy of a nuclear reactor can be obtained by attaining a mixing of the flows of coolant in the lower plenum of the fuel assemblies of the nuclear reactor, a high flow stability of the two-phase flow in the fuel assemblies and a small pressure loss in the core. To achieve this, there is provided a coolant guide tube 60 that communicates with the inside of the fuel support piece 12 inserted in the control rod guide tube and the passage 16, wherein there is formed a coolant guide passage 61 along which coolant descends in the area outside of the coolant guide tube in the fuel assemblies from opening 79. The coolant guide passage along which the coolant descends from the opening is formed in an area outside of the coolant guide tube in the fuel support piece.

Claims14

Dependent claims

A boiling water nuclear reactor in which coolant is supplied to fuel assemblies in a pressure vessel from a lower plenum below the fuel assemblies comprising:

means for improving flow stability of a two-phase flow of said coolant in said fuel assemblies of said boiling water nuclear reactor by providing an increased path length of said coolant flow, said flow stability means including a first passage connected to a coolant entrance of said lower plenum for effecting downward flow of said coolant, and a second passage communicating with said first passage for effecting upward flow of said coolant from the first passage, whereby said coolant is supplied to said fuel assemblies from said second passage and enabling flow stability of the two-phase flow of said coolant in said fuel assemblies.

Dependencies are inferred from the claim text.

Nuclear reactor

Life of this patent

Nuclear reactor

Life of this patent

Abstract

Claims14