A Simulation of The Influence of The Thermal Properties of Rocks to The Excavated Holes with Heat using Finite Element Method

[[abstract]]由於用核廢料所產生之長期衰變熱會對我們的環境造成影響，各國未來對於用過核燃料的處理方式傾向以深層地質處置(deep geological disposal)法作為最終處置。衰變熱會隨時間增加而衰減，衰變時間長逹幾萬年之久，這期間處置母岩及處置孔的溫度場會因此直接受到衰變熱與熱傳導的作用而產生變化。 本研究主要探討核廢料深層處置之岩盤熱特性對受熱開挖孔之影響，且以瑞典KBS-3V 處置孔為設計規範分析5組材料，應用美國洛薩拉摩國家實驗室 (Los Alamos National Laboratory) Zyvoloski 等研究員於1988 年所發展之有限元素程式FEHM程式模擬岩體熱傳導係數及不同網格節點數之單孔與雙孔網格間其溫度之變化。[[abstract]]Due to the long-term decay heat of the nuclear waste material which will cause the influence on our environment all the countries tend to permanently dispose the nuclear waste by using Deep Geological Disposal method One of the most distinguished characteristics of the nuclear waste is that the decay heat will be released and decayed for a long period which can be last for several ten thousand years As the surface of the disposal hole is the direct contact area with the canister containing the nuclear waste the decay heat released from the canister can be conducted to the surrounding host rock Hence the temperature in the field will be changed in the period The major purpose of this research is to study the influence of the thermal properties of rocks to the excavated holes with heat from nuclear waste in deep geological disposal In this research the design code of Swedish KBS-3V and five materials were used A Finite Element program FEHM originally developed by Zyvoloski et al in 1998 in Los Alamos National Laboratory was employed in this thesis The numerical analysis includes the simulation of the temperature variation with various rock heat conduction coefficients and various nodal numbers of finite element meshes in the simulation of single and double hole