放射性核種傳輸之數值模擬驗證與應用

Numerical simulation of radionuclide transport of verification and application

林子誠(Tzu-Cheng Lin)

指導教授 ： 陳瑞昇

國立中央大學/地球科學學院/應用地質研究所/碩士(2015年)

摘要

國際上高放射性廢棄物最終處置設施多位於深層地層，以阻絕放射性污染物進入人類生活圈，放射性核種傳輸數值模式常被使用作為處置設施功能安全評估工作之重要安全分析模式工具，幫助我們更清楚了解放射性核種的傳輸現象。在現有的解析模式中已發展可完整考慮在穩態均流場條件下之多核種衰變鏈傳輸解析解，因此將可以提供放射性核種傳輸數值模式之重要驗證參考依據，而數值模式則對處理非穩態、非均質、非等向地質環境之複雜流場較有彈性。本研究使用HYDROGEOCHEM 4.5s作為模擬在地下環境之放射性核種傳輸安全分析工具，並與前述解析解進行案例比較驗證，兩者在同時考慮源項衰變、吸附相污染物的衰變與多物種衰變鏈等影響皆有相當吻合結果，並進一步假設忽略吸附相衰變對核種傳輸結果的影響進行模擬探討，研究結果顯示不考慮吸附相衰變會高估母核種的濃度，並且低估子核種的濃度。未來在功能安全評估實務應用上，可以結合放射性核種傳輸解析解與數值模擬之優點以提升安全分析之可靠度。

關鍵字

核種傳輸 ； 多物種衰變鏈 ； 源衰變 ； HYDROGEOCHEM4.5s

並列摘要

International final disposal of nuclear waste chooses the deep formation to block the radioactive contaminants from entering the human living area. Therefore radionuclide transport numerical model often used as an important tool for safety analysis performance assessment of disposal facilities. Existing analytical solutions has been developed that can consider under steady-state flow field of multi-species decay chain transmission. Therefore it can provide important method of radionuclide transport numerical model to verification. In this study, we use HYDROGEOCHEM 4.5s as a performance assessment tool to simulate radioactive nuclides underground transportation and verification with the aforementioned analytical solution. Consider includes the source decay, the adsorption phase decay of pollutants and the multi-species decay chain. The result of verification is quite consistent.

並列關鍵字

nuclide transport ； decay chain ； source decay ； HYDROGEOCHEM4.5s

參考文獻

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