由於支撐現代生活能源所需的石化能源逐漸耗盡，並且對環境造成如空氣污染以及溫室效應等衝擊。尋找替代性能源是刻不容緩的議題。固態氧化物燃料電池(Solid oxide fuel cell)工作溫度大約在攝氏八百度到一千度之間，比起其他燃料電池，有著高機械強度、寬廣的燃料選擇、以及可合併氣渦輪機提升效率等優點。

　　本文提出一個SOFC/GT複合系統，以甲烷為燃料，系統中包含一外部重整器，以及一後燃器。後燃器將殘餘的甲烷、氫氣、以及一氧化碳完全燃燒之後， 提供重整以及將空氣、燃料預熱所需的熱。我們以熱力學以及電化學反應建立系統之數學模型，計算系統運作下每一元件作功、所須熱量的情形、以及各元件的進出口狀況。藉由改變重整器之溫度與壓力，以及SOFC堆中之溫度、壓力、氫氣使用率等來分析系統表現的不同，以及系統各元件進出口狀態的改變。最後加入可用能之分析，釐清隨著參數的改變系統各元件可用能損失的情形。

　Because the exhausting of petrolic energy which supporting modern life and using petrolic energy has done the environment great damages such as air pollutions and greenhouse effect, it is of great urgency to find an alternative energy solution. The solid oxide fuel cell (SOFC)has a working temperature about 800°C to 1000°C. Comparing to other types of fuel cells, SOFC does have many advantages like high mechanism strength, wide range of fuel selections, and the likelihood of combining a gas turbine to increase system efficiency.

　In this lecture we suggest a SOFC/GT combine system, which uses methane as fuel and includes an external reformer and an afterburner. After the complete combustion of residues of methane, hydrogen, and carbon monoxide, the afterburner would provide the heat that needed by the reforming of the methane and the preheating of the fuel and the air. We use knowledge of thermodynamics and electric chemical processes to build a mathematical model of the system, and calculate the work done, the heat needed, and inlet/outlet states of each component when system is working. By changing reformer`s pressure and temperature and SOFC stack’s pressure, temperature, and utilization rate of hydrogen, we analyze the differences of system performances and all system components` inlet/outlet states. Finally we bring out availability analysis to clarify availability looses in all system components as changing system parameters.

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