Dynamic Analysis of Planar Solid Oxide Fuel Cell Models With Different Assumptions of Temperature Layers

2008 ◽  
Vol 6 (1) ◽  
Author(s):  
Handa Xi ◽  
Jing Sun
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Model Performance ◽  
System Optimization ◽  
Solid Oxide ◽  
High Fidelity ◽  
Oxide Fuel ◽  
Baseline Model ◽  
Trade Off ◽  
The Impact

As solid oxide fuel cell (SOFC) technology is rapidly evolving, high-fidelity mathematical models based on physical principles have become essential tools for SOFC system design and analysis. While several SOFC models have been developed by different groups using different modeling assumptions, little analysis of the effects of these assumptions on model performance can be found in literature. Meanwhile, to support system optimization and control design activities, a trade-off often has to be made between high fidelity and low complexity. This trade-off can be influenced by the number of temperature layers assumed in the energy balance to represent the SOFC structure. In this paper, we investigate the impact of the temperature layer assumption on the performance of the dynamic planar SOFC model. Four models of co-flow planar SOFCs are derived using the finite volume discretization approach along with different assumptions in the number of temperature layers. The model with four temperature layers is used as the baseline model, and the other models aimed at reducing the complexity of the baseline model are developed and compared through simulations as well as linear analysis. We show that the model with as few as two temperature layers—the solid structure and air bulk flow—is able to capture the dynamics of SOFCs, while assuming only one temperature layer results in significantly large modeling error.

Solid Oxide Fuel Cell System and the Economical Feasibility

2006 ◽  
Vol 3 (3) ◽  
pp. 242-253 ◽  
Author(s):  
Erkko Fontell ◽  
Tho Phan ◽  
Timo Kivisaari ◽  
Kimmo Keränen
Keyword(s):  
Fuel Cell ◽  
Natural Gas ◽  
Solid Oxide Fuel Cell ◽  
Cell System ◽  
Solid Oxide ◽  
Maintenance Cost ◽  
Oxide Fuel ◽  
Market Conditions ◽  
The Impact ◽  
Economical Feasibility

In the paper, a solid oxide fuel cell (SOFC) system is briefly described and its economical feasibility in three different applications is analyzed. In the feasibility analysis, the SOFC system is part of commercial applications where energy is used for power and heat generation. In the economical analysis, the three applications have different load profiles which are studied separately at different geographical locations with associated local energy market conditions. The price for natural gas and electricity varies by location, leading to a different feasibility condition for stationary fuel cell application as well as for other distributed generation equipment. In the study, the spark spread of natural gas and electricity is used as a base variable for the analysis. The feasibility is analyzed in the case of an electricity-only application as well as with two combined heat and power applications, where an economical value is assigned to the produced and consumed heat. The impact on economical competitiveness of possible incentives for the generated fuel cell power is estimated. A sensitivity analysis with different fuel cell-units’ electrical efficiency, maintenance cost, and payback period is presented. Finally, the maximum allowed investment cost levels for the SOFC system at different locations and market conditions is presented.

The impact of sulfur on the performance of a solid oxide fuel cell (SOFC) system operated with hydrocarboneous fuel gas

2009 ◽  
Vol 189 (2) ◽  
pp. 1127-1131 ◽  
Author(s):  
Florian P. Nagel ◽  
Tilman J. Schildhauer ◽  
Josef Sfeir ◽  
Alexander Schuler ◽  
Serge M.A. Biollaz
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Fuel Gas ◽  
The Impact

Modelling the impact of creep on the probability of failure of a solid oxide fuel cell stack

2014 ◽  
Vol 34 (11) ◽  
pp. 2695-2704 ◽  
Author(s):  
Fabio Greco ◽  
Henrik Lund Frandsen ◽  
Arata Nakajo ◽  
Mads Find Madsen ◽  
Jan Van herle
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Probability Of Failure ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Fuel Cell Stack ◽  
The Impact

scholarly journals Performance of a Natural Gas Solid Oxide Fuel Cell System With and Without Carbon Capture

2020 ◽  
Vol 143 (4) ◽  
Author(s):  
Arun K. S. Iyengar ◽  
Brian J. Koeppel ◽  
Dale L. Keairns ◽  
Mark C. Woods ◽  
Gregory A. Hackett ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Natural Gas ◽  
Solid Oxide Fuel Cell ◽  
Co2 Capture ◽  
System Performance ◽  
Carbon Capture ◽  
System Optimization ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Utility Scale

Abstract The fuel cell program at the United States Department of Energy (DOE) National Energy Technology Laboratory (NETL) is focused on the development of low-cost, highly efficient, and reliable fossil-fuel-based solid oxide fuel cell (SOFC) power systems that can generate environmentally friendly electric power with at least 90% carbon capture. NETL’s SOFC technology development roadmap is aligned with near-term market opportunities in the distributed generation sector to validate and advance the technology while paving the way for utility-scale natural gas (NG)- and coal-derived synthesis gas-fueled applications via progressively larger system demonstrations. The present study represents a part of a series of system evaluations being carried out at NETL to aid in prioritizing technological advances along research pathways to the realization of utility-scale SOFC systems, a transformational goal of the fuel cell program. In particular, the system performance of utility-scale NG fuel cell (NGFC) systems with and without carbon dioxide (CO2) capture is presented. The NGFC system analyzed features an external auto-thermal reformer (ATR) feeding the fuel to the SOFC system consisting of planar anode-supported SOFC with separated anode and cathode off-gas streams. In systems with CO2 capture, an air separation unit (ASU) is used to provide the oxygen for the ATR and for the combustion of unutilized fuel in the SOFC anode exhaust along with a CO2 purification unit to provide a nearly pure CO2 stream suitable for transport for usage in enhanced oil recovery (EOR) operations or for storage in underground saline formations. Remaining thermal energy in the exhaust gases is recovered in a bottoming steam Rankine cycle while supplying any process heat requirements. A reduced order model (ROM) developed at the Pacific Northwest National Laboratory (PNNL) is used to predict the SOFC performance. The ROM, while being computationally effective for system studies, provides other detailed information about the state of the stack, such as the internal temperature gradient, generally not available from simple performance models often used to represent the SOFC. Such additional information can be important in system optimization studies to preclude operation under off-design conditions that can adversely impact overall system reliability. The NGFC system performance was analyzed by varying salient system parameters, including the percent of internal (to the SOFC module) NG reformation—ranging from 0 to 100%—fuel utilization, and current density. The impact of advances in underlying SOFC technology on electrical performance was also explored.

scholarly journals The impact of NiO on microstructure and electrical property of solid oxide fuel cell anode

2005 ◽  
Vol 6B (11) ◽  
pp. 1124-1129 ◽  
Author(s):  
Yan Li ◽  
Zhong-yang Luo ◽  
Chun-jiang Yu ◽  
Dan Luo ◽  
Zhu-an Xu ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Electrical Property ◽  
Solid Oxide Fuel Cell ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Cell Anode ◽  
Fuel Cell Anode ◽  
The Impact

Hardware-Based Simulation of a Fuel Cell Turbine Hybrid Response to Imposed Fuel Cell Load Transients

2006 ◽  
Author(s):  
Thomas P. Smith ◽  
Comas L. Haynes ◽  
William J. Wepfer ◽  
David Tucker ◽  
Eric A. Liese
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Gas Turbine ◽  
Pressure Vessels ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Electrical Load ◽  
Fuel Cell Stack ◽  
Thermal Transients ◽  
The Impact

Electrical load transients imposed on the cell stack of a solid oxide fuel cell/gas turbine hybrid power system are studied using the Hybrid Performance (HyPer) project. The hardware simulation facility is located at the U.S. Department of Energy, National Energy Technology Laboratory (NETL). A computational fuel cell model capable of operating in real time is integrated with operating gas turbine hardware. The thermal output of a modeled 350 kW solid oxide fuel cell stack is replicated in the facility by a natural gas fired burner in a direct fired hybrid configuration. Pressure vessels are used to represent a fuel cell stack's cathode flow and post combustion volume and flow impedance. This hardware is used to simulate the fuel cell stack and is incorporated with a modified turbine, compressor, and 120 kW generator on a single shaft. For this study, a simulation was started with a simulated current demand of 307 A on the fuel cell at approximately 0.75 V and an actual 45 kW electrical load on the gas turbine. An open loop response, allowing the turbine rotational speed to respond to thermal transients, was successfully evaluated for a 5% current reduction on the fuel cell followed by a 5% current increase. The impact of the fuel cell load change on system process variables is presented. The test results demonstrate the capabilities of the hardware-in-the-loop simulation approach in evaluating hybrid fuel cell turbine dynamics and performance.

Cfd Analysis of Heat Transfer in a Microtubular Solid Oxide Fuel Cell Stack

2014 ◽  
Vol 35 (3) ◽  
pp. 293-304 ◽  
Author(s):  
Paulina Pianko-Oprych ◽  
Ekaterina Kasilova, ◽  
Zdzisław Jaworski
Keyword(s):  
Heat Transfer ◽  
Fuel Cells ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Heat Losses ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Reaction Heat ◽  
Flux Profile ◽  
The Impact

Abstract The aim of this work was to achieve a deeper understanding of the heat transfer in a microtubular Solid Oxide Fuel Cell (mSOFC) stack based on the results obtained by means of a Computational Fluid Dynamics tool. Stack performance predictions were based on simulations for a 16 anodesupported mSOFCs sub-stack, which was a component of the overall stack containing 64 fuel cells. The emphasis of the paper was put on steady-state modelling, which enabled identification of heat transfer between the fuel cells and air flow cooling the stack and estimation of the influence of stack heat losses. Analysis of processes for different heat losses and the impact of the mSOFC reaction heat flux profile on the temperature distribution in the mSOFC stack were carried out. Both radiative and convective heat transfer were taken into account in the analysis. Two different levels of the inlet air velocity and three different values of the heat losses were considered. Good agreement of the CFD model results with experimental data allowed to predict the operation trends, which will be a reliable tool for optimisation of the working setup and ensure sufficient cooling of the mSOFC stack.

Dynamic Simulation of a Solid Oxide Fuel Cell System for Micro Combined Heat and Power Application

2013 ◽  
Vol 336-338 ◽  
pp. 695-699 ◽  
Author(s):  
Ying Wei Kang ◽  
Wei Huang ◽  
Yang Xue ◽  
Guang Yi Cao ◽  
Heng Yong Tu
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Thermal Inertia ◽  
System Optimization ◽  
Combined Heat And Power ◽  
Cell System ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Dynamic Simulations ◽  
Chp System

In the past decade, developing solid oxide fuel cell (SOFC) systems for micro combined heat and power applications (micro-CHP, 1-10 kWe) is one of the hot spots in the world energy field. To meet the requirements for system optimization and control design of SOFC micro-CHP systems, in this paper a dynamic model of an SOFC micro-CHP system is developed, based on which dynamic simulations are also carried out. Simulation results show that the present model can reflect the behavior of the SOFC micro-CHP system quite well; the influence of one component on another is an important factor to determine system dynamic behavior; as the system comprises many components and concerns different physical and chemical processes, it has dynamic processes with several kinds of time scales; for the air preheating need, the heat-exchange area of air pre-heater is quite big, which leads to its big thermal inertia, and causes the dynamic process lasting for several ten thousands of seconds.

Comparison of Dynamic Planar SOFC Models With Different Assumptions of Temperature Layers in Energy Balance

2006 ◽  
Author(s):  
Handa Xi ◽  
Jing Sun
Keyword(s):  
Energy Balance ◽  
Model Performance ◽  
System Optimization ◽  
Low Complexity ◽  
High Fidelity ◽  
Baseline Model ◽  
Trade Off ◽  
Depth Analysis ◽  
Design Activities ◽  
Finite Volume Approach

As Solid Oxide Fuel Cell (SOFC) technology is quickly developing and continuously evolving, high-fidelity mathematical models based on physical principles become essential tools for SOFC system design and analysis. Different modeling assumptions, however, are used by different groups, while in-depth analysis of influence of these assumptions on model performance can not be found in literature. Meanwhile, to support system optimization and control design activities, a trade-off often has to be made between high fidelity and low complexity. One factor that could define this trade-off is the number of temperature layers assumed to represent the SOFC structure. In this paper, we investigate different models for co-flow planar SOFCs that are derived using the finite volume approach with different assumptions of temperature layers in energy balance. The model with four temperature layers is used as the baseline model, and the other models aimed at reducing the complexity of the baseline model are developed and compared through simulations for different steady state and transient scenarios. Simulation results show that the model with as few as two temperature layers—solid structure and air flow—is able to capture the dynamics of SOFCs, while assuming only one temperature layer results in substantially different dynamic characteristics.

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