Design Optimization of High-Power, Liquid Anode AMTEC.

A high power, liquid-anode, Alkali Metal Thermal-To-Electric Conversion (AMTEC) unit design is developed and optimized. Optimized parameters include: number of BASE elements; spacing between BASE elements and their arrangement in rows and columns; electrode’s surface area per BASE element; and number and diameter of the orifices in the internal radiation heat shield. The effects of these parameters on the size, mass and performance of the AMTEC unit when operating at BASE and condenser temperatures of 1123 K and 670 K, respectively, are discussed. The specific power of the Na AMTEC unit is maximum at a WRh1.5 electrode’s surface area of 140.8 cm2 per BASE element. A total number of 128 BASE elements, electrically connected in series, deliver the nominal power of 5.6 kWe which is 84% of the peak power (6.7 kWe). The BASE elements are arranged in 4 rows of 32 elements each, resulting in a nearly square footprint, minimum mass and parasitic heat losses, and maximum specific power and efficiency. At the nominal operating current of ∼100 A, the radiation and conduction parasitic heat losses amount to only 7% of the total heat input. The optimized AMTEC unit design measures 594 mm × 410 mm × 115 mm, weighs 44.3 kg, and has an efficiency of 27.6% at the nominal power of 5.6 kWe (a specific power of 125 We/kg). For a 100-kWe power system with a nuclear reactor core exit temperature of ∼1180 K, 18 of these units would provide excellent redundancy and reliability in energy conversion. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]