"Solid oxide fuel cells (SOFC) offer high electrical efficiency of power generation, multifuel operation and internal reforming capabilities among other benefits. However, flow maldistribution of gas reactants among cells of the fuel cell stack and uneven utilization of the active cell area is one of the reasons for the performance loss in the scale-up process or even a stack failure at high electric load, high fuel utilization conditions. Efficient and uniform supply of reactants and removal of products was previously studied using computational fluid dynamics (CFD) methods. These methods, although accurate, require significant computing power, computing time and offer limited optimization capabilities. The flow networks modeling approach offers accuracy sufficient for the engineering design together with the accelerated optimization capabilities. It shows accuracy sufficient for engineering design optimization. In the proposed model, design oriented mass and flow distribution model of the SOFC stack, stack manifolds and flow channels are simulated as a network of differential hydraulic resistances. In order to simulate hydraulic network operation under electric load conditions, differential model of the SOFC cell (DCM) will be implemented and combined with the hydraulic networks model. In the DCM model, principal geometrical parameters of the cell will be implemented (electrolyte/electrode thickness, electrode porosity) together electrochemical performance characteristics, including polarization characteristics. The modeling results will explain physical mechanisms of flow distribution in the SOFC stack. They will also allow optimization of combined manifold and flow channels geometry under both no-load and electric load operation."