Improved Tank in Series Model for the Planar Solid Oxide Fuel Cell

Abstract

Models of different complexity are required in the iterative process of designing a solid oxide fuel cell (SOFC). Models having less complexity and computational dexterity are the ideal ones at the early stages. This work presents the development of an improved tank in series reactor model of the SOFC operating in cocurrent, countercurrent, and cross-current flow directions. The model, which accounts for the charge balances in the electrodes and electrolyte in addition to the component balances and the energy balances, is used for simulating the potentiostatic operation of the cell. The simulation results from the TSR model indicate the influence of flow direction on the steady state and dynamic performances of the cell. Among different flow directions, the coflow case is the most favorable for the planar SOFC, with improved performance. In response to a voltage step increase, the coflow case provides the most uniform transient behavior at different points of the cell. Despite the coflow direction, in which temperature dominates the slow dynamics of the local current density, in the low temperature regions of the counterflow and cross-flow cases, the slow dynamics of the current density tends to be characterized by the initial undershoot followed by a slower transient response that is due to the combined effects of the diffusion resistance within the porous electrode, hydrogen accumulation toward the fuel outlets, and the influence of the PEN temperature.

Solid oxide fuel cell reactor analysis and optimisation through a novel multi-scale modelling strategy

“…Even though the model is 0D at the compartment scale, it becomes a 1D, 2D and 3D model at the channel, cell and stack scales, respectively, as shown in Figure 1. The governing conservation and constitutive equations are taken from Hosseini et al (2010) and Danilov et al (2011b) and adapted for a single compartment. The model parameters and operating conditions are the same as those used in Hosseini et al (2010).…”

“…The governing conservation and constitutive equations are taken from Hosseini et al (2010) and Danilov et al (2011b) and adapted for a single compartment. The model parameters and operating conditions are the same as those used in Hosseini et al (2010). The model equations and the simulation parameters are summarised in Tables A1 and A2.…”

“…Extensive simulation and sensitivity analysis of the SOFC compartment model is outside the scope of this study because many other works have been published at this scale. The essential model used in this research was validated by Hosseini et al (2010) and Danilov et al (2011b).…”

A tank in series model for alkaline fuel cell in cogeneration of hydrogen peroxide and electricity

“…At steady state, the rate of mass transfer in Eqs. (10) and (11) is balanced by the rate of electrochemical reaction.…”

“…In earlier studies we reported a dynamic TSR model for a PEMFC [9] and planar SOFC [10]. These improved TSR models include species and energy balances in gas channels and liquid electrolyte phase together with charge balance equations defined at the electrode-electrolyte interfaces.…”