temperaturwechselpruefgeraet for the investigation of the core fuel elements

摘要

1,231,490. Fuel elements. COMMISSARIAT A L'ENERGIE ATOMIQUE. 16 Dec., 1968 [5 Jan., 1968], No. 59712/68. Heading G6C. Apparatus for the study of thermal cycling of fuel elements comprises a gas-tight container 1 in which a gas pressure can be maintained, a carrier 7 in which a fuel element 9 is placed, a heating coil 13 wound on a sleeve 15 in which the carrier 7 is slidably fitted, and a heat insulation system between the sleeve 15 and the inner wall of the container 1. The gas, e.g. CO 2 , is introduced into the container 1 through a pipe 17. The heat insulation system is made up on the one hand of a stationary portion formed by a stainless steel sheet 19 helically wound on a support 21 rigidly fixed to the container 1 and, on the other hand, by a movable portion formed of a stainless steel sheet 25 helically wound on a support 27 provided with a drive shaft 29 by means of which it is moved longitudinally (or rotated). Windows 23, 35 are provided in the sheets 19, 25, respectively. When the windows 23, 35 are opposite one another heat flow by convection is freely established, but this is suppressed when the movable portion is shifted longitudinally (or rotated) so that the windows are no longer opposite one another. The container 1 is cooled either by natural convection in air by means of fins 37 or by water circulation within an outer casing 39.