Light-water reactor fuel assembly (alternatives), a light-water reactor, and a fuel element of fuel assembly

A fuel assembly for a light water nuclear reactor with a square shape in the plan view, the fuel assembly comprising:

• a frame defining a square coordinate grid of positions;
• a first plurality of fuel elements that are arranged in the rows and columns of the square coordinate grid in cross-section, each of the first plurality of fuel elements has a four-lobed profile forming spiral ribs, and comprises an alloy of fissile material;
• and
• a second plurality of fuel elements that are arranged in the rows and columns of the square coordinate grid in cross-section and encircle the first plurality of fuel elements;
• wherein the first plurality of fuel elements includes a plurality of primary first fuel elements that are arranged in the rows and columns in a midsection of the square coordinate grid, as well as a plurality of secondary first fuel elements that are arranged in rows and columns of the square coordinate grid that surround the plurality of primary first fuel elements;
• wherein each of the plurality of primary first fuel elements has a larger width across corners than that of each secondary first fuel element.