Performance evaluation and parametric analysis of AMTEC/TEG hybrid system

• Published in: Energy conversion and management Vol. 154; pp. 118 - 126
• Main Authors: Wu, Shuang-Ying, Zhang, Yi-Chen, Yang, Han, Xiao, Lan
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 15.12.2017; Elsevier Science Ltd
• Subjects: Alkali metal thermal electric converter (AMTEC); Alkali metals; AMTEC (converter); AMTEC/TEG hybrid system; electric generators; Electrodes; Energy balance; equations; evaporation; geometry; Heat transfer; Hybrid systems; Mathematical models; Operating temperature; Parameters; Parametric analysis; Parametric statistics; Performance evaluation; Studies; temperature; Temperature effects; Thermoelectric conversion; Thermoelectric generator (TEG); Thermoelectric generators; Thermoelectricity; Thermoelectric conversion; Thermoelectric generator (TEG); Parametric analysis; Alkali metal thermal electric converter (AMTEC); AMTEC/TEG hybrid system
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2017.10.046

•Developed a general mathematical model of AMTEC/TEG hybrid system with particular emphasis on the energy balance.•Employing the geometric and load parameters to characterize the feature of AMTEC/TEG hybrid system.•Different parameters present quite discrepant effects on the performance.•The selection of parameter values is of great importance for the application of hybrid system. A general mathematical model of the AMTEC/TEG hybrid system consisting of alkali metal thermal electric converter (AMTEC) and thermoelectric generator (TEG) has been developed, in which the load parameters and main geometric parameters were considered. Instead of specifying some parameters, the evaporating temperature and condensing temperature of the AMTEC as well as the operating temperature of the TEG subsystem were determined by solving energy balance equations. Results show that electrode current density has a quite noticeable influence on both AMTEC subsystem and TEG subsystem. The maximum conversion efficiencies for AMTEC and AMTEC/TEG are 27.42% and 31.33%, respectively. Besides, it is interesting to note that the optimal value of the ratio of thermoelectric module area to electrode area is always near 0.2 regardless of the ratio of evaporator heat transfer area to electrode area. The length of thermoelectric arms l and the ratio of the thermoelectric couple area to the total area of the thermoelectric module b are critical factors, b ≥ 0.55 and l ≤ 11 mm should be satisfied to obtain a compact and low-cost system.