| 摘要 |
978,375. Nuclear reactors. EUROPEAN ATOMIC ENERGY COMMUNITY (EURATOM). Feb. 26,1963 [March 1, 1962], No. 7729/63. Heading G6C. Movement of the fuel elements 4 with fluid flow along the vertical coolant channel 1 of a fluid cooled nuclear reactor, which flow is upwards in the direction of the arrows f is prevented by means of a stepped plug 8 sitting in a portion of the channel 1 of enlarged cross-section, the area of the bottom surface of the plug being slightly less than that of the cross-section of the channel 1 while the area of the top surface is greater, a by-pass 10 extending from the bottom of the channel 1 near the cooling fluid entry conduit 2 to the top of the channel 1 above the top surface of the plug 8. The by-pass 10 enables the pressure in the channel 1 below the fuel elements to be exerted on the top surface of the plug 8 and, since the area of this surface is greater than the cross-sectional area of the channel 1, the fuel elements 4 remain in position, a finger 9 at the bottom end of the plug 8 engaging the top fuel element 4. Stop means (not shown) are provided in the channel 1 below the fuel elements 4 to limit their downward movement when they are not supported by the flow of cooling fluid. |
