本論文探討熱學遮罩由暫態至定常態過程中，其熱隱形與熱保護之效果。熱遮罩之設計以結構簡單易製造且材料為常見容易取得的天然物質為重點，為了能夠更好的滿足計算所得的各向異性熱導係數以及非均質的密度與比熱乘積，提出四層的熱遮罩。以研究暫態熱隱形性能為方向，首先比較設計之遮罩、雙層遮罩以及單純背景之間溫度分布的差異，接著定義特定參數並模擬分析取得數值，以定量比較差異大小。除了數值分析以外亦進行實驗，使用紅外線熱像儀來量測溫度分布，再將結果與模擬相互驗證。由於裝置與空氣間的熱交換以及裝置各零件之間的間隙，可以發現實驗之各區域溫度稍微低於模擬結果，且零件交接處有溫降現象；儘管有以上這些實驗誤差，但熱遮罩之效果依然存在。在進行電腦模擬時，選擇兩條量測線來定量估計設計之遮罩與雙層遮罩之性能，模擬結果顯示在暫態的大部分時間，四層遮罩相較於雙層遮罩在量測線上高低溫差較小，並且四層遮罩在量測線上平均溫度較接近無遮罩時的背景溫度，因此四層遮罩在暫態熱隱形的性能較雙層遮罩良好。最後，使用一個基於保護區平均溫度與初始溫度的差異的暫態品質因數，來評估所設計之四層遮罩在保護區的性能，而數值與實驗的結果均顯示，相比於無遮罩的情況，四層遮罩擁有相對較長的熱保護效果。

This thesis investigates the thermal cloaking and shielding performance in a thermal cloak, from transient to steady state. The thermal cloak design is relatively simple, and the materials are common natural materials. To better match the analytical requirement for anisotropic heat conductivity and inhomogeneous product of density and specific heat capacity, the proposed thermal cloak uses four layers. In order to study the transient thermal cloaking performance, the temperature distribution differences among the designed cloak, bilayer cloak and the background were first compared, by defining specific parameters and conducting computer simulation to allow a quantitative comparison. In addition to numerical analysis, experiment was carried out using an infrared camera to measure the temperature distribution, and the results were verified with the simulation. The simulation results show that during most of the transient evolution, the four-layer cloak has a lower temperature difference between the maximum and minimum value on the measuring lines than that for the bilayer cloak. Also, the average temperature on the measuring lines is closer to the background temperature without cloak for the four-layer cloak compared to the bilayer cloak. Hence, the transient performance of the four-layer cloak is better than the bilayer cloak. Finally, the performance of the designed four-layer cloak were assessed using a transient figure of merit based on the difference between the transient average temperature in the cloaked region and the initial temperature. Both numerical and experimental result demonstrate the effectiveness of cloaking area a relatively long period compared to the case without cloak.

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