Patent Number: 
Section: abstract

The invention pertains to a nuclear fuel rod for a nuclear reactor. The fuel rod has a cladding. The cladding's external surface has a surface texture that includes a rib. The rib coils around the circumference of the cladding. The rib length forms a sequence of continuous rib loops uniformly spaced along an axial length of the cladding. The ratio of rib height to cladding diameter is greater than or equal to 0.0134 and less than or equal to 0.0268. The ratio of rib height to rib width is greater than or equal to 0.8 and less than or equal to 1.2. A pitch measured between adjacent rib loops is greater than or equal to 9× rib height and less than or equal to 12× rib height. The rib enhances fuel rod heat transfer in a region downstream of grid mixing vanes, where turbulence is dissipated.