IIST之TRACE模型建立與實驗案例驗證

The Developments and Verifications of IIST TRACE Model

莊偉翔

指導教授 ： 施純寬 ； 王仲容

國立清華大學/原子科學院/核子工程與科學研究所/碩士(2012年)

摘要

本論文之研究是以核研所整體系統測試設施(IIST)為對象，建立其電腦模型，並利用TRACE程式執行事故案例的計算，最後將計算結果與IIST實驗數據相比較，進行案例分析與TRACE程式驗證。本文包含的實驗案例有二，一是小破口冷卻水流失案例、二是電廠全黑案例。
第一階段因壓力槽的組件不同而建立了兩種IIST TRACE模型：管路式壓力槽、3-D幾何壓力槽。透過小破口冷卻水流失案例的結果比較，表現較佳的3-D幾何壓力槽被選擇用來進行下一步的研究。第二階段同樣利用小破口冷卻水流失案例，進行了兩種熱水流模式的靈敏度分析，分別為臨界流模式與反向極限流限制模式，經過實驗數據的比對，獲得最佳化的臨界流模式雙相流加權因子、次冷態流加權因子、以及反向極限流限制模式的係數，接著再針對破口尺寸進行靈敏度分析。第三階段為電廠全黑案例的計算和分析，此案例的模型是由第一階段的模型修改而來，雖然兩者的起始條件不同，但經過初始值的調整後仍可得到適合的穩態結果，並能成功模擬出與實驗接近的暫態表現。為了解一次側壓力在暫態前期預測的壓力值偏高的原因，接著進行初始壓力值、功率曲線、暫態延遲等三項因素對於一次側壓力造成的影響。這些結果將在論文中描述。
目前IIST模型已經建立完成，並獲得多項實驗案例的比較結果和靈敏度分析，部分結果雖然有待加強，但是模型本身已經可以提供研究者在研究馬鞍山電廠的種種事故後，進行結果的驗證和比對，相信對於了解壓水式核能發電廠的各種熱水流現象有很大的幫助。

關鍵字

核研所整體系統測試設施 ； TRACE ； 小破口冷卻水流失

並列摘要

This research is focused on building up the computer models of INER Integral System Test (IIST) facility for experiment calculations by TRACE. Two experiments are included, one is the IIST Small Break Loss Of Coolant Accident (SBLOCA) the other one is Station Blackout (SBO). After doing the calculations, the results are compared to verify the TRACE code and make the experiments analysis.
First, two different IIST TRACE models which include a pipe-vessel model and a 3-D vessel component model have been built. The steady state and transient calculation results show that both TRACE models have the ability to simulate the related IIST experiments. Comparing with IIST SBLOCA experiment data, the 3-D vessel component model has shown better simulation capabilities so that it has been chosen for all further thermal hydraulic studies. Second, the sensitivity studies of multipliers in choked flow model; and two correlation constants in CCFL model are made. As a result, an appropriate set of multipliers and constants can be determined. So far, a verified IIST TRACE model with 3D vessel component, and fine-tuned choked flow model and CCFL model is established for further studies on IIST experiments in the future. Third, the SBO accident of IIST TRACE model was established. Compare with the experiment data, each of the result on steady state and transient calculations are in good agreement except the primary system pressure. In order to figure out the difference, sensitivity studies on initial pressure, power curve, power delay time are discussed. Up to now, the IIST TRACE model is built up with different kinds and verified thermal hydraulic models. Applying this model to evaluate the performance of PWR could promote the understanding of the thermal hydraulic phenomena in safety analysis.

並列關鍵字

IIST ； TRACE ； SBLOCA

參考文獻

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