Thermal modeling and efficiency of a dual-stage sodium heat engine [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 333.79 Energy
• Thông tin xuất bản: Washington, D.C. : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Energy Efficiency and Renewable Energy ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2018
• Mô tả vật lý: Size: p. 603-609 : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 255721
• Chủ đề: 1. 14 solar energy; 2. 30 direct energy conversion; 3. 42 engineering; 4. Alkali-metal thermal electric converter (amtec); 5. Beta"-alumina solid-electrolyte (base); 6. Thermally regenerative electrochemical system (tres); 7. Thermo- electro-chemical conversion

Tóm tắt

In this paper, a thermal design of an axisymmetric dual-stage sodium thermal electrochemical converter (Na-TEC) is presented, where a reduced-order finite-element model is used in conjunction with a Na-TEC thermodynamic model to determine the total parasitic heat loss of this dual-stage design. A number of simplifications are applied in the reduced-order model to decrease the computational time while maintaining acceptable accuracy. These include the use of effective thermal conductivities to account for complex corrugated geometries and apparent surface emissivities to accommodate the effect of radiation shields. Furthermore, a simplified analytical model is developed to account for conduction bypass through the Na-TEC liquid-return path. An iterative procedure between the finite-element and thermodynamic models is described in detail, and the thermal performance of the design proposed herein is analyzed. According to this analysis, a maximum efficiency of 29% and a maximum power output of 125 W can be achieved.