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Annual Report

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The Target Complex loop TC-1 was originally conceived as part of an accelerator-driven system (ADS) pilot plant that was designed and developed by the Institute of Physics and Power Engineering (IPPE) and Experimental and Development Organization (EDO) “Gidropress” in Obninsk, Russia, under the International Science and Technology Center Project #559 in 1998. It was to be used as the target in a 1 MWth ADS experiment run off of the LANSCE proton accelerator at Los Alamos National Laboratory (LANL). When the U.S. transmutation program changed priorities from accelerator-driven systems towards nuclear fission reactors, the TC-1 loop was brought to UNLV to be developed as an academic research tool.

Liquid lead-bismuth eutectic (LBE) is employed as a spallation target, as well as a heat transfer fluid or coolant, in the TC-1 loop. The TC-1 loop can play a role as a testing facility in the U.S. to support research in heavy liquid metal coolant for the nuclear industry. During a thermal and engineering test of the TC-1 loop in 2005 at UNLV, it was observed that the existing control algorithm led to a very slow convergence to the target temperature setting, and also showed unstable oscillatory behavior. The existing algorithm was not robust enough to handle the complicated heating system of the TC-1 loop, where nine heating zones or elements are compacted in one tight container. This interaction and coupling between each heating zone, as well as a heat disturbance from a low efficiency electromagnetic (EM) pump, caused the overall temperature control system to be complex and nonlinear.

The primary objective of this task was to study and modify the coupling effect between heating zones and the existing control algorithm to achieve precise temperature control in the TC-1 loop system. Safety concerns, the alarm system, and a user-friendly design became the secondary objective.


Accelerator-driven systems; Automatic control; Electromagnetic pumps; Eutectic alloys; Monitoring and Controlling and Scram Protection System (MCSPS); Temperature control


Controls and Control Theory | Nuclear Engineering | Oil, Gas, and Energy