本文將太陽能光電及史特林引擎與固態氧化物燃料電池系統結合，藉由熱電共生以有效提升發電廠之發電量及總效率，同時提升燃料利用率，且根據環境條件變化能夠在不同模式下運作。太陽能光電的應用使得此系統可於日間透過甲烷重組反應製造氫氣並儲存，夜間無日照時則以固態氧化物燃料電池與史特林引擎利用氫氣進行發電。
本文可分為兩部分。第一部分透過計算流體力學方法分析逆向流螺旋板式熱交換器於紊流中的特性，結果顯示在螺旋板式熱交換器中，紊流的效應更勝於流道曲率，而局部對流熱傳係數之變化趨勢與場協同原理分析結果一致。當螺旋圈數增加或雷諾數下降時，傳熱效能與尤拉數皆隨之增加，本文亦提出紐塞數經驗公式，可作為在工業上設計螺旋板式熱交換器時之參考依據。其性能評估結果可應用於複合發電系統達到熱回收之目的。
第二部分則應用有限時間熱力學建立太陽能光電/固態氧化物燃料電池/史特林引擎複合系統之數學模型，探討電堆燃料利用率、氮氣含量、日照强度與熱交換器螺旋圈數對於輸出功率、儲熱量、效率與熱電比之效應，並提出不同最佳化目標對應之系統參數組合。由結果可知，當系統操作於PV-SOFC-SE與SOFC-SE模式下時，分別可得到最高的輸出功率與效率，且此系統於長期運轉下，可作為分散式發電系統供應社區電力與熱能需求。

For the purpose of improving the power generation and overall efficiency of power plants, cogeneration is an effective approach. In this dissertation, a hybrid power generation system is proposed integrating the Stirling engine and photovoltaics into SOFC system. The energy utilization can be enhanced as well. This hybrid system is designed to be able to operate at three modes according to environmental conditions. The application of photovoltaics allows the system to produce hydrogen from methane at daytime and generate electricity using SOFC and Stirling engine when no solar irradiance is received.
This dissertation is divided into two parts. In Part I, the CFD analysis of countercurrent SPHE for turbulent flow is performed. The evidence shows that the turbulence is dominant over the curvature of channel in SPHE. The variation of local convective heat transfer is derived with a consistent result provided by field synergy principle. The heat transfer effectiveness and Euler number increase with increasing number of turns of spiral and decreasing Reynolds numbers. A new Nusselt number correlation of SPHE is also proposed. The performance evaluation of SPHE can be adopted in Part II for building the hybrid system.
In Part II, a mathematical model of hybrid power generation system combining solid oxide fuel cell, Stirling engine, and photovoltaics is established. The effects of stack fuel utilization, nitrogen/hydrogen ratio, solar irradiance, and number of turns of SPHE on output power, heat storage, efficiency, and HPR value of system are investigated. The combinations of system parameters for different optimization targets are given as well. The results show that the highest power output and efficiency are achieved at PV-SOFC-SE and SOFC-SE modes, respectively. The 24-hour operation shows that the proposed hybrid system is capable of supporting the power and heat demand in a community for decentralized applications.

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