Parametric analyses of AMTEC multitube cells and recommendation for revised cell design

The OSC-derived procedure for analyzing multitube AMTEC cells described in the preceding paper was used to determine the effects of various design parameters on the cells’ performance. Particular attention was paid to the length, diameter, and wall thickness of the standoff that connects the evaporator at the bottom of the wick with the plenum at the bottom of the BASE tubes. Those standoff dimensions have a pronounced effect on the cell’s performance and the adequacy of its temperature margin (to ensure that the high-pressure sodium does not condense in the BASE tube, causing shorting of the multitube cell). The paper displays parametric trade-off curves between those variables, and also presents the computed results of varying the plenum cover thickness, the cell wall thickness and reflectivity, the condenser temperature and reflectivity, and the cell heat input and voltage output. Those parametric studies culminate in an OSC recommendation for a revised multitube AMTEC cell design.