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构建一个以天然气为燃料的SOFC-CHP系统,推导SOFC传热传质及电化学方程,建立各个组件的数学模型,编写计算程序,对发电功率为1kW的家用SOFC-CHP系统在设计工况下进行性能模拟并探讨不同系统参数对性能的影响。计算结果表明:在设计工况下,系统热电联供效率远高于电池单独发电的效率;此外,随着燃料入口流量的增大,系统发电功率存在一个最大值,燃料利用率与发电效率不断减小,系统热电联供效率不断增大,SOFC的温度梯度分布则越来越平缓;同时发现降低过量空气系数可以提高该CHP系统的性能。 相似文献
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固体氧化物燃料电池(SOFC)是一种高效低污染的新型能源。建立了以天然气为燃料的固体氧化物燃料电池和燃气轮机(GT)联合发电系统的计算模型,并对具体系统进行计算。结果表明:SOFC与GT组戍的联合发电系统,发电效率可达68%(LHV);加上利用的余热,整个系统的能量利用率可以超过80%。文中还分析了SOFC的工作压力、电流密度等参数对系统性能的影响,提高工作压力,可以增加电池发电量,提高系统的发电效率;而电流密度的增大将使SOFC及整个系统的发电量降低。 相似文献
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为延长固体氧化物燃料电池(SOFC)的寿命、提高系统性能,以5 kW平板式SOFC系统为研究对象,在满足功率需求和温度约束的条件下,探究其通过寻优最佳的操作参数组合以实现最高的系统效率。首先采用模块化建模方法,基于工作机理建立SOFC独立发电系统的模型。其次,基于所建立的系统模型,通过定义4个操作参数,并结合系统的热电约束,形成SOFC系统效率优化问题。针对该优化问题,提出一种结合元启发式优化算法的两级优化方案,即将操作参数按照对SOFC系统的影响分为两级,对第一级操作参数进行离散取值,对第二级操作参数采用麻雀搜索算法进行优化。结果表明,所提优化方案可获得全局最优操作点,使SOFC系统满足功率需求和温度约束条件且系统效率达到最优。 相似文献
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固体氧化物燃料电池(SOFC)/燃气轮机(GT)混合系统以其高效、低污染排放的优点受到各国尤其是西方发达国家的重视,被认为是解决21世纪能源与环境问题的关键技术之一.计算机仿真方法是目前研究SOFC/GT混合系统的主要方法之一.本文利用Aspen Custom Modeler 仿真平台对一回热器空气再热式SOFC/GT系统进行了仿真分析,给出了设计工况下混合循环各部件节点的状态参数值,分别就压比、燃料电池电流密度和燃料利用率对系统发电效率的影响进行了仿真分析.仿真结果表明,系统总发电效率随压比的关系曲线呈抛物线型,随着压比的增大,系统的发电效率先增大后减小.系统总发电效率与电流密度成反比关系,而与燃料利用率成正比;燃料电池的发电效率与电流密度和燃料利用率均成反比. 相似文献
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基于顶层循环的SOFC/MGT混合发电系统,提出了CO2准零排放SOFC/MGT混合发电新系统:经电池堆阳极产物分离出氢气后采用纯氧燃烧,用冷凝的办法除去水蒸气,从而捕获CO2气体。阴极产物与分离得到的氢气则在另外的后燃室燃烧。结合案例分析了该混合发电新系统的性能,研究了CO2液化温度对系统的影响。与其它CO2准零排放发电系统相比,本研究提出的CO2准零排放SOFC/MGT混合发电新系统具有更高发电效率。研究结果将为CO2准零排放发电系统的研究提供有益参考。 相似文献
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Siyu Chen Houcheng Zhang Fu Wang He Miao Jiapei Zhao Chunfei Zhang Jinliang Yuan 《International Journal of Hydrogen Energy》2021,46(42):22062-22078
Apart from electricity, solid oxide fuel cell (SOFC) generates a great deal of high-grade exhaust heat, which must be immediately removed to guarantee SOFC's normal operation. To harvest the exhaust heat and improve the overall energy conversion efficiency, a new hybrid system model based upon a SOFC, a vacuum thermionic generator (VTIG) and a thermoelectric generator (TEG) is first proposed. Considering the main thermodynamic-electrochemical irreversible effects, the performance indicators assessing the whole system performance are mathematically derived. In comparison with the performance of sole SOFC, the effectiveness and feasibility of the presented system are verified. Numerical calculation examples illustrate that maximum achievable power density (MAPD) and its corresponding efficiency, exergetic efficiency and exergy destruction rate are, respectively, 26.8%, 9.8%, 9.8% and 8.8% larger than that of the stand-alone SOFC. Exhaustive sensitivity analyses are further conducted to investigate the impacts of various parameters on the tri-generation system performance. Results indicate that the grain size and average pore diameter of electrodes in SOFC and the thermoelectric element number in TEG can be optimized to maximize the hybrid system power density. 相似文献
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An energy analysis of three typical solid oxide fuel cell (SOFC) power systems fed by methane is carried out with detailed thermodynamic model. Simple SOFC system, hybrid SOFC‐gas turbine (GT) power system, and SOFC‐GT‐steam turbine (ST) power system are compared. The influences of air ratio and operative pressure on the performance of SOFC power systems are investigated. The net system electric efficiency and cogeneration efficiency of these power systems are given by the calculation model. The results show that internal reforming SOFC power system can achieve an electrical efficiency of more than 49% and a system cogeneration efficiency including waste heat recovery of 77%. For SOFC‐GT system, the electrical efficiency and cogeneration efficiency are 61% and 80%, respectively. Although SOFC‐GT‐ST system is more complicated and has high investment costs, the electrical efficiency of it is close to that of SOFC‐GT system. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Salha Faleh Sghaier Tahar Khir Ammar Ben Brahim 《International Journal of Hydrogen Energy》2018,43(6):3542-3554
A parametric study is conducted on a hybrid SOFC-GT cycle as part of a national program aiming to improve the efficiency of the actual gas turbine power plants and to better undertake the future investigations. The proposed power plant is mainly constituted by a Gas Turbine cycle, a SOFC system, and an ammonia water absorption refrigerating system. An external pre-reformer is installed before the SOFC. Heat recovery systems are adopted to valorize the waste heat at the SOFC and GT exhausts. The gas from the SOFC exhaust is also used as additional supply for the combustion chamber. An extraction is performed on the gas Turbine in order to feed the SOFC cycle by thermal heat flux at medium pressure.The equations governing the electrochemical processes, the energy and the exergy balances of the power plant components are established. Numerical simulation using EES software is performed. The influences of key operating parameters, such as humidity, pre-reforming fraction, extraction fraction from the Gas Turbine and fuel utilization on the performances of the SOFC-GT hybrid system are analyzed. Obtained results show that the integration of the SOFC enhances significantly the hybrid overall cycle efficiency. The increase of the ambient temperature and humidity reduces the system efficiencies. The utilization factor has a negative effect on the SOFC temperature and voltage. That leads to a decrease in the power plant performances. While the pre-reforming fraction, has a positive effect on the indicated parameters. 相似文献
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This paper mainly studied the solid oxide fuel cell (SOFC)–micro gas turbine (MGT) hybrid power system. The key parameters that greatly influence the overall system performance have been studied and optimized. The thermodynamic potential of improving the hybrid system performance by integrating SOFC with the advanced thermal cycle system is analyzed. The optimization rules of main parameters of SOFC‐MGT hybrid power system with the turbine inlet temperature (TIT) of MGT as a constraint condition are revealed. The research results show that TIT is a key parameter that limits the electrical efficiency of hybrid power system. With the increase of the cell number, both the power generation efficiency of the hybrid cycle power system and TIT increase. Regarding the hybrid system with the fixed cell number, in order to get a higher electrical efficiency, the operating temperature of SOFC should be enhanced as far as possible. However, the higher operating temperature will result in the higher TIT. Increasing of fuel utilization factor is an effective measure to improve the performance of hybrid system. At the same time, TIT increases slightly. Both the electrical efficiency of hybrid power system and TIT reduce with the increase of the ratio of steam to carbon. The achievements obtained from this paper will provide valuable information for further study on SOFC‐MGT hybrid power system with high efficiency. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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For a solid oxide fuel cell (SOFC) and micro gas turbine (MGT) hybrid system, optimal control of load changes requires optimal dynamic scheduling of set points for the system's controllers. Thus, this paper proposes an improved iterative particle swarm optimization (PSO) algorithm to optimize the operating parameters under various loads. This method combines the iteration method and the PSO algorithm together, which can execute the discrete PSO iteratively until the control profile would converge to an optimal one. In MATLAB environment, the simulation results show that the SOFC/MGT hybrid model with the optimized parameters can effectively track the output power with high efficiency. Hence, the improved iterative PSO algorithm can be helpful for system analysis, optimization design, and real‐time control of the SOFC/MGT hybrid system. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Solid oxide fuel cell (SOFC) is an energy conversion device that produces electricity directly from fossil fuels through electrochemical reactions. Intermediate and low temperature SOFCs (IT/LT, 300–800 °C SOFCs) are the main strains of the world SOFC R&D now. The exhaust gas of SOFC has high value in use. So SOFC is often integrated into a hybrid system with other power systems. Research shows that the electrical efficiency and the total efficiency of a hybrid system can be about 60% and 80% higher than an independent one. In this paper, the performance of intermediate temperature SOFC hybrid system was analyzed. Based on presenting a steady-state mathematical model of ITSOFC, the steady-state model of each designed system was presented. Results show that a hybrid system can achieve high efficiency. The results of this research can be useful in design and application for polygenerations integrated by SOFCs. 相似文献
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Haoxiang Lai Nor Farida Harun David Tucker Thomas A. Adams 《International Journal of Hydrogen Energy》2021,46(7):5612-5629
This study compares two SOFC/GT (solid oxide fuel cell with gas turbine) hybrid systems to that of two standalone SOFC systems via eco-technoeconomic analyses that account for long-term degradation effects. Four cases were examined: 1) standalone SOFC plant without a steam bottoming cycle; 2) standalone SOFC plant with a steam bottoming cycle; 3) SOFC/GT hybrid plant without a steam bottoming cycle; and 4) SOFC/GT with a steam bottoming cycle. This study employed a real-time 1D SOFC model with an empirical degradation calculation integrated with steady-state balance-of-plant models. Simulations used Matlab Simulink R2017a, Aspen Plus V10, and Python 3.7.4 with a pseudo steady-state approach. The results showed that, with some trade-offs, the SOFC/GT hybrid plant with the steam bottoming cycle is the best option, with an overall efficiency of 44.6% LHV, an LCOE (levelized cost of electricity) of $US 77/MWh, and a CCA (cost of CO2 avoided) of -$US 49.3/tonneCO2e. The sensitivity analysis also indicated that SOFC/GT hybrid plants were less sensitive to SOFC price compared to standalone SOFC plants. The sensitivity analysis indicated that using a larger gas turbine and replacing the SOFC stack less frequently was the better design choice for the SOFC/GT hybrid plant. 相似文献
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Study on zero CO2 emission atmospheric pressure SOFC hybrid power system integrated with OTM 下载免费PDF全文
In order to further reduce the energy consumption of CO2 capture from the traditional SOFC hybrid power system, based on the principle of energy cascade utilization and system integration, a zero CO2 emission atmospheric pressure solid oxide fuel cell (SOFC) hybrid power system integrated with oxygen ion transport membrane (OTM) is proposed. The oxygen is produced by the OTM for the oxy‐fuel combustion afterburner of SOFC. With the Aspen‐plus software, the models of the overall SOFC hybrid power systems with or without CO2 capture are developed. The thermal performance of new system is investigated and compared with other systems. The effects of the fuel utilization factor of SOFC and the pressure ratio between two sides of OTM membrane on the overall system performance are analyzed and optimized. The research results show that the efficiency of the zero CO2 emission atmospheric pressure SOFC hybrid power system integrated with OTM is around 58.36%, only 2.48% lower than that of the system without CO2 capture (60.84%) but 0.96% higher than that of the zero CO2 emission atmospheric pressure SOFC hybrid system integrated with the cryogenic air separation unit. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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《International Journal of Hydrogen Energy》2022,47(64):27690-27702
In order to improve the power generation efficiency of fuel cell systems employing liquid fuels, a hybrid system consisting of solid oxide fuel cell (SOFC) and proton exchange membrane fuel cell (PEMFC) is proposed. Utilize the high temperature heat generated by SOFC to reform as much methanol as possible to improve the overall energy efficiency of the system. When SOFC has a stable output of 100 kW, the amount of hydrogen after reforming is changed by changing the methanol flow rate. Three hybrid systems are proposed to compare and select the best system process suitable for different situations. The results show that the combined combustion system has the highest power generation, which can reach 350 kW and the total electrical efficiency is 57%. When the power of the tail gas preheating system is 160 kW, the electrical efficiency can reach 75%. The PEM water preheating system has the most balanced performance, with the electric power of 300 kW and the efficiency of 66%. 相似文献