A spatially resolved physical model for transient system analysis of high temperature fuel cells

Abstract

IntroductionThe U.S. Department of Energy has devoted significant effort towards technological breakthroughs for highly efficient low emission electricity production [1e4]. Rising oil prices, the possibility of carbon taxation, and unnerving dependence on foreign energy sources stimulated the federal government's interest in clean energy sources that can meet new greenhouse gas emission targets. Fuel cells promise the dual benefits of high efficiency energy conversion and extremely low pollutant emissions, but adoption of the technology has been limited by high initial capital costs and lack of market acceptance. The challenges include poor economies of scale in manufacturing due to the relatively high materials costs and surface-area scaling characteristics, the complexity of the balance of plant and control systems, a lack of proven system durability, and operations and maintenance costs. Available online at www.sciencedirect.com journal h om epa ge: www.elsev ier.com/locate/he i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 8 ( 2 0 1 3 ) 7 9 3 5 e7 9 4 6

Dynamic model of a micro-tubular solid oxide fuel cell stack including an integrated cooling system

“…The transfer coefficient used by McLarty et al [13] is in good accordance with other values published in literature. Cui et al [32] and Zhu and Kee [33] are using a value of 0.5, while Leonide et al [34] published a value of 0.65 and García-Camprubí et al [35] is varying the parameter between 0.25 and 1.5.…”

“…The considered species are methane, carbon monoxide, carbon dioxide, hydrogen and water vapor on the anode side, as well as oxygen and nitrogen on the cathode side [13,14].…”

“…The calculation of the arrangement factor is shown in Equation (32). The mean velocity inside the air channel can be expressed using the velocity of air at the inlet of the channel and the void fraction to Table 1 Thermal conductivity, heat capacity and density of typical interconnect, coolingtube and PEN material [13,19,31]. …”

“…The total losses at the cathode due to activation, diffusion and concentration losses can be calculated using Equation (41) [13,14].…”

“…Additionally, the ohmic loss can be calculated using the area specific resistance, as illustrated in Equation (42) [13,14].…”