摘要
本論文研究的對象為核四廠版本PCTRAN-ABWR程式，針對緊緊急爐心冷卻系統(ECCS) 大幅修改，增進模擬程式的多樣性及功能，並在保持原有程式架構前提下擴建系統功能。藉由緊急爐心冷卻系統(ECCS)擴充，我們在維持原有PCTRAN-ABWR程式架構與功能下找出最佳的程式修改方向，也成功地改進熱交換器理論模式及流程流量壓降理論模式，並使用封閉通道壓降模式成功地模擬HPCF流量與流程壓降模式，可作為日後PCTRAN-ABWR程式改進之先導範本。 緊急爐心冷卻系統(ECCS)包括三個子系統—反應爐爐心隔離冷卻系統(RCIC)、高壓爐心灌水系統(HPCF)、及餘熱移除系統(RHR)。本論文改進重點包括 (1) 擴充三個完全獨立分區之緊急爐心冷卻系統(ECCS)設備 (2) 擴充緊急爐心冷卻系統(ECCS)多種運轉模式之運轉與連鎖(Interlock)邏輯 (3) 釐清緊急爐心冷卻系統(ECCS)取水量、注水量及熱焓改變量對於圍阻體乾井、濕井、反應爐之影響 (4) 改進緊急爐心冷卻系統(ECCS)流程壓降模式 (5) 改進餘熱移除系統(RHR)系統熱交換器模式。 改進後之系統模式驗證工作以模擬器驗證資料[1]與LOCA事故分析報告[2]為基礎，藉由數個核電廠事故案例驗證流程流量與壓降計算模式、熱交換器模組運算模式及動作邏輯；此外藉由喪失全部飼水事故探討不同分區電源失效所造成ECCS系統失效的影響。
並列摘要
The thesis focuses on the improvements and modifications of the PCTRAN-ABWR, a simulation code for the Lungmen Nuclear Power Plant, about the Emergency Core Cooling system (ECCS). The methodology to modify the PCTRAN-ABWR code and to improve its process flow and pressure model and the heat exchanger model can be examples for future modifications. The ECCS system includes of three subsystems, the Reactor Core Isolation Cooling subsystem, High Pressure Core Flooder subsystem and Residual Heat Removal subsystem. The approaches of the thesis are as followings: (1)Three independent divisions of ECCS are established. (2)The essential operation modes and interlock logics of ECCS system are improved. (3)The Thermal-Hydraulic relationships among the ECCS, the reactor core model and the containment are clarified. (4)The models for the process flow and pressure drop of ECCS are improved. (5)The RHR heat exchanger model is improved. As benchmarks of the ECCS modifications, the TRACG Benchmark Transient Analysis for the LUNGMEN Simulator Validation Project [1] and the SAFER/GESTR-Loss of Coolant Accident Analysis [2] are utilized. The discussions on the cases of LOCA and the impacts due to the delay of SCRAM time and the failure of the ECCS on the case of loss of all feedwater flow can be examples for future analysis.