Kilo Temperature Loop CFD Analysis

CFD Analysis of Kilo Temperature Loop
Shri Prakash Guptab, Ananta Borgohaina, V. Shankarb, N.K.Maheshwaria, P.K. Vijayana a Reactor Engineering Division, Bhabha Atomic Research Centre, Trombay, Mumbai b Dept. of Chemical Engineering, Indian Institute of Technology, Kanpur

Abstract
Lead–Bismuth Eutectic (LBE) is increasingly getting more attraction as the coolant for advanced reactor systems. It is also the primary coolant of Compact High Temperature Reactor (CHTR), being designed at BARC. A facility Liquid Metal Loop (LML) is already in operation since 2009 for natural circulation loop of LBE up to 550 °C. Another high temperature facility called Kilo Temperature Loop (KTL) has been installed in BARC for thermal hydraulics and material
Natural circulation loop is the representative of primary heat transport system of a nuclear reactor. In a closed system without the use of pumps, circulation of fluids is generally maintained by thermal convection. This is why natural circulation is designed for the so-called Generation IV nuclear reactors, which like to employ passive safety and reliability. As a result, more and more attention has been given to natural circulation in the advanced reactor designs. A heat source and a heat sink connected by piping are the essential part of natural circulation loop. Here the heat sink is placed at higher elevation to promote natural circulation. The flow takes place due to the buoyancy force caused by density gradient resulting from temperature gradient. The natural circulation flow rate depends on the loop resistance and the temperature difference between the hot leg and the cold leg, as determined by the power level and the heat sink capacity.
Lead- Bismuth Eutectic (LBE) is a eutectic alloy of lead (44.5%) and bismuth (55.5%) [5]. LBE exhibits low melting point and high boiling point, enables us to operate the system in low pressure. LBE do not react with air or water, in contrast to sodium and NaK which ignite spontaneously in air and react explosively with water. LBE has high boiling point (1670°C) compared to sodium-based liquid metal coolants , because of this LBE is more
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