A nuclear fuel assembly including: a plurality of elongated nuclear fuel rods having an extended axial length; at least a lowermost grid supporting said fuel rods in an organized array and having unoccupied spaces defined therein adapted to allow flow of fluid coolant therethrough and past said fuel rods when said fuel assembly is installed in a nuclear reactor; a plurality of guide thimbles extending along said fuel rods through and supporting said grid; a bottom nozzle disposed below said grid, below lower ends of said fuel rods, supporting said guide thimbles and having openings therethrough to allow the flow of fluid coolant into said fuel assembly, the bottom nozzle comprising: a substantially horizontal plate, orthogonal to the axis of the fuel rods, having an upper face directed substantially toward the lowermost grid and a lower face on the underside of said horizontal plate with said openings extending therethrough for the flow of coolant, characterized in that at least some of said openings in at least one of either the upper face or the lower face having a funnel-like first appendage (96, 92) respectively extending above the upper face or below the lower face, as the case may be, around at least some of the openings in the one of the upper face or the lower face with an opening at the first appendage's substantially highest extent, in the case of the upper face or lowest extent, in the case of the lower face, having a larger diameter than a diameter of the opening (90, 100) in the one of the upper face or the lower face, an internal wall of the first appendage substantially gradually decreasing in diameter from the opening at the first appendage's substantially highest extent in the case of the upper face or substantially lowest extent in the case of the lower face, until the wall of the first appendage transitions to the opening in the upper face or lower face, as the case may be and wherein a lip of at least some of the openings at the first appendage's substantially highest extent in the case of the upper face or lowest extent in the case of the lower face, have a scalloped contour. a plurality of elongated nuclear fuel rods having an extended axial length; at least a lowermost grid supporting said fuel rods in an organized array and having unoccupied spaces defined therein adapted to allow flow of fluid coolant therethrough and past said fuel rods when said fuel assembly is installed in a nuclear reactor; a plurality of guide thimbles extending along said fuel rods through and supporting said grid; a bottom nozzle disposed below said grid, below lower ends of said fuel rods, supporting said guide thimbles and having openings therethrough to allow the flow of fluid coolant into said fuel assembly, the bottom nozzle comprising: a substantially horizontal plate, orthogonal to the axis of the fuel rods, having an upper face directed substantially toward the lowermost grid and a lower face on the underside of said horizontal plate with said openings extending therethrough for the flow of coolant, characterized in that at least some of said openings in at least one of either the upper face or the lower face having a funnel-like first appendage (96, 92) respectively extending above the upper face or below the lower face, as the case may be, around at least some of the openings in the one of the upper face or the lower face with an opening at the first appendage's substantially highest extent, in the case of the upper face or lowest extent, in the case of the lower face, having a larger diameter than a diameter of the opening (90, 100) in the one of the upper face or the lower face, an internal wall of the first appendage substantially gradually decreasing in diameter from the opening at the first appendage's substantially highest extent in the case of the upper face or substantially lowest extent in the case of the lower face, until the wall of the first appendage transitions to the opening in the upper face or lower face, as the case may be and wherein a lip of at least some of the openings at the first appendage's substantially highest extent in the case of the upper face or lowest extent in the case of the lower face, have a scalloped contour. a substantially horizontal plate, orthogonal to the axis of the fuel rods, having an upper face directed substantially toward the lowermost grid and a lower face on the underside of said horizontal plate with said openings extending therethrough for the flow of coolant, characterized in that at least some of said openings in at least one of either the upper face or the lower face having a funnel-like first appendage (96, 92) respectively extending above the upper face or below the lower face, as the case may be, around at least some of the openings in the one of the upper face or the lower face with an opening at the first appendage's substantially highest extent, in the case of the upper face or lowest extent, in the case of the lower face, having a larger diameter than a diameter of the opening (90, 100) in the one of the upper face or the lower face, an internal wall of the first appendage substantially gradually decreasing in diameter from the opening at the first appendage's substantially highest extent in the case of the upper face or substantially lowest extent in the case of the lower face, until the wall of the first appendage transitions to the opening in the upper face or lower face, as the case may be and wherein a lip of at least some of the openings at the first appendage's substantially highest extent in the case of the upper face or lowest extent in the case of the lower face, have a scalloped contour.