Patent Number: 053751531
Section: claims

1. A fuel rod for a light water reactor fuel assembly having elongated fuel rods, comprising: (a) a part length fuel rod portion containing nuclear fuel, the part length fuel rod portion having a downstream end;  (b) a reflex upper end fitting for separating at least a portion of the liquid and the vapor of two phase flow, the reflex upper end fitting disposed axially above the part length fuel rod and in contact with the downstream end of the part length fuel rod, the reflex upper end fitting comprising:  (a) a part length fuel rod;  (b) a plurality of generally substantially parallel disposed elongated fuel rods, the part length fuel rod and plurality of fuel rods arranged in spaced parallel relation;  (c) means for supporting the fuel rods and the part length fuel rod in the spaced parallel relation;  (d) a reflex upper end fitting for separating at least a portion of the liquid and the vapor of two phase flow, the reflex upper end fitting disposed axially above the part length fuel rod and in contact with the downstream end of the part length fuel rod, the reflex upper end fitting comprising a section having a diameter tapering downwardly into a reduced diameter and flaring thereafter into a second diameter terminating in a sharp break at a line around its perimeter, the tapering and flaring producing a smooth flow path for propelling fluid flowing therealong, radially inwardly and then outwardly from the downstream end of the part length fuel rod; and  (e) connecting means for connecting the reflex upper end fitting to the part length fuel rod. 2. A nuclear reactor fuel assembly comprising: