Liquid metal pumps for enabling heat transfer at extreme temperatures

Abstract

Thermal energy is fundamental to most power generation and many industrial processes, and because of the entropy associated with it, is the most valuable at the highest temperature. To use this heat, it must be transported and molten metals are an ideal heat transfer media because they can have high temperature stability and high heat transfer coefficients. The ability to pump a fluid is key because it enables circulation and includes the thermal and chemical constraints seen by an entire system, with the added challenge of dynamic sealing, stress, and wear. In this thesis, I report the first successful demonstration of an all ceramic mechanical pump, that was used to continuously circulate liquid tin at ~ 1200-1400°C, in an all ceramic circulation loop, for 72 hours without failure. The design of a medium temperature (600°C) liquid metal pump and an ultra-high temperature (>2000°C) is also presented. This first of a kind demonstration represents a major technological breakthrough, because it now enables heat transfer using a liquid, above 1000°C. This capability is enabling, because the notion of transferring, storing and converting heat at such extreme temperatures has been previously considered infeasible. This new ability represents a major step forward for the fields of heat transfer, energy, and chemical/materials processing and many new concepts are enabled by this approach.