Patent Number: 
Section: claims

1. An apparatus for delivering cooled fuel salt into a reactor core comprising:an exterior wall;an interior wall surrounding the reactor core and spaced apart from the exterior wall such that a plenum is formed between the exterior wall and the interior wall, the interior wall separating the reactor core from the plenum, the interior wall provided with a plurality of perforations penetrating the interior wall and permitting flow of nuclear fuel salt between the reactor core and the plenum;a top wall connecting the exterior wall and the interior wall; anda plenum inlet defined at least partially by the exterior wall and positioned opposite the top wall for receiving cooled nuclear fuel salt into the plenum, wherein the plenum has a tapered shape proximate the top wall, the plenum having a radial thickness that is greater at the plenum inlet than adjacent the top wall, and wherein the tapered shape of the plenum begins at a height above the plenum inlet. 2. The apparatus of claim 1, wherein the plurality of perforations are arranged into at least two horizontal rows of perforations. 3. The apparatus of claim 1, wherein at least one of the perforations in the plurality of perforations is a cylindrical hole through the interior wall having a central axis that is not parallel with a horizontal plane that is defined by the top wall. 4. The apparatus of claim 1, wherein at least one of the perforations in the plurality of perforations is a frustoconically shaped hole through the interior wall. 5. The apparatus of claim 1, wherein at least one of the perforations in the plurality of perforations is a frustoconically shaped hole through the interior wall having a central axis that is not parallel with a horizontal plane that is defined by the top wall. 6. The apparatus of claim 1, wherein the exterior wall tapers inwardly towards the interior wall proximate the top wall. 7. The apparatus of claim 1, wherein the plurality of perforations are spaced at different levels within the interior wall. 8. The apparatus of claim 7, wherein more perforations of the plurality of perforations are disposed proximate the plenum inlet than the top wall. 9. The apparatus of claim 1, wherein a base end of both of the exterior wall and the interior wall opposite of the top wall are positioned along a same horizontal plane that is parallel to the top wall.