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In the present study, a numerical simulation and experimental studies of an alkali-metal thermoelectric energy converter (AMTEC) system were carried out. The present, unique AMTEC model consists of an evaporator, a b-alumina solid electrolyte (BASE) tube, a condenser, and an artery cable wick. The key points for operation of the present AMTEC were 1100 K in the evaporator and 600 K in the condenser. A numerical model based on sodium-saturated porous wicks was developed and shown to be able to simulate the AMTEC system. The simulation results show that the AMTEC system can generate up to 100 W with a given design. The AMTEC system developed in the present work and used in the practical investigations could generate an electromotive force of 7 V. Artery wick and evaporator wick structures were simulated for the optimum design. Both sodium-saturated wicks were affected by numerous variables, such as the input heat power, cooling temperature, sodium mass flow rate, and capillary-driven fluid flow. Based on an effective thermal conductivity model, the presented simulation could successfully predict the system performance. Based on the numerical simulation, the AMTEC system operates with efficiency near 10% to 15%. In the case of an improved BASE design, the system could reach efficiency of over 30%. The system was designed for 0.6 V power, 25 A current, and 100 W power input. In addition, in this study, the temperature effects in each part of the AMTEC system were analyzed using a heat transfer model in porous media to apply to the computational fluid dynamics at a predetermined temperature condition for the design of a 100-W AMTEC prototype. It was found that a current density of 0.5 A/cm 2 to 0.9 A/cm 2 for the BASE is suitable when the temperatures of the evaporator section and condenser section are 1100 K and 600 K, respectively.

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