Numerical Analysis of Segmented Thermoelectric Generator Applied in Heat Pipe Cooled Nuclear Reactor

The power system of heat pipe cooled nuclear reactor can be divided into dynamic conversion system and static conversion system. Thermoelectric generator (TEG) is a typical static conversion device, which can directly convert heat energy into electric energy. The combination of heat pipe cooled nuclear reactor and TEGs can bring many advantages, such as compact structure, high inherent safety, no auxiliary mechanical equipment and low noise. However, the maximum core temperature could exceed 1 000 K, and ordinary thermoelectric generators can not operate in such high temperature. To solve this problem, the use of segmented thermoelectric generator (STEG) in the power system of heat pipe cooled nuclear reactor is a method worthy of research. STEG can play an important role in the heat pipe cooled nuclear reactor. But there is not enough literature to study the application of STEG in heat pipe cooled nuclear reactor. STEG usually splices two or three thermoelectric materials with the highest power generation efficiency in different temperature ranges. In this way, STEG can obtain a high thermoelectric conversion efficiency in a wide temperature range (usually above 600 K). Therefore, a kind of STEG for heat pipe cooled nuclear reactor was designed. In this paper, a conceptual design of a heat pipe cooled nuclear reactor with STEGs was proposed. The single STEG and single channel model were explored by COMSOL software. A three-dimensional finite element model of STEG’s performance in heat pipe cooled nuclear reactor was established. STEG was designed to compose of bismuth telluride and skutterudite, and its geometric structure and performances were optimized. Numerical simulation was carried out under steady-state conditions to determine the optimal STEG’s geometry. Then, the optimized STEG was connected with the heat pipe to form a single channel model for simulation to explore its performances. When the temperature difference reaches 550 K, the maximum STEGs’ output power reaches 0.374 W, and the maximum ...