Gaseous Core Reactors and Nudear-Pumped Lasers

Gaseous Core Reactors and Nudear Pumped Lasers 

A U(95%)Fe-Heliura Circulating Gas Critical Assembly, D. M. Barton. G. A. Jarvis, J. F. Davis IIKLASL) 

During shutdown conditions the UFg is stored in a bottle inside the oven at room temperature and pressures as a solid. To charge the canister for a critical operation, the UFg lines are filled with He at 600 Torr pressure, the UFg supply bottle is valved off and the He gas is circulated for one or two hours in the UFg loop to preheat the canister and lines. The UFg in the bottle is then heated to the gas phase by turning the oven to 90°C. The He gas gtream is next valved through the UFg bottle and carries the UFg out of the bottle and around the loop. 

UFg can be removed from thh He by cOoling the bottom of the supply bottle while the oyen keeps the valves ppen. After all of the UFg is condensed from the mixture the bottle is valved off end allowed to cool. Eighty-seyen percent of the mixture is in the canister at one time. The amount of UFg transferred from the bottle to the manifold is determined by removing the supply bottle and weighing it This procedure provides the necessary inventory control for experimental measurements and fissionable material accounting. 

The axial and radial flux distributions were measured by activation of Al-U alloy wires. The radial flux is essentially flat biit the axial fission distribution falls off 

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