本研究以三維逆向計算流體力學方法配合超定的實驗溫度數據及最小平方法來預測對於管式熱交換器置於固態氧化物燃料電池之簡化熱箱內，加熱之矩形管的熱傳率、石蠟的吸收熱、適當的流動模型和三維自然對流熱傳特性。透過測試不同的流動模型可以發現，在無相變化材料時使用零方程式模型其溫度之均方根誤差最小，且與經驗公式所求得之結果最貼切；當在第二根圓管中填入相變化材料時，採用標準壁函數之標準k-ε模型於所有模型中具有最佳的準確度。
結果顯示，降低兩圓柱擺放之角度能夠使空腔內之溫度趨於對稱，避免空腔近壁處出現高溫。改變圓柱壁間距與圓柱離加熱器距離雖會影響空腔內的流動現象，然而僅在特定情況下才能使腔內溫度分布對稱，以達到降低空腔近壁處溫度之效果。加入相變化材料僅可些微降低腔內溫度約1 K左右，然由於相變化材料擺放之位置離加熱器較遠且與熱源無直接接觸，導致傳熱效率不佳，相變化材料無法達到其熔點，故吸熱效果不如預期。因此本研究不推薦僅透過對流將熱傳遞至相變化材料來達到降低空腔溫度的效果。

This research examines a small-scale hot box model with two cylinder tubes and a rectangular heater. Temperature data is collected using 10 K-type thermocouples. After conducting grid independence analysis for mesh generation, Computational Fluid Dynamics (CFD) is utilized to obtain numerical results. The unknown heat source is determined via the least squares method. The study then selects an appropriate turbulence model based on comparing the root mean square error (RMSE) between numerical and experimental results. .The effect on temperature contour and streamline resulted from 4 different parameters are discussed.
A zero-equation model is found suitable for cases without Phase Change Material (PCM), while the standard k-ε model is more appropriate for cases involving PCM. Increasing the inclination angle of two horizontal tubes can increase the convective heat transfer coefficient ((h_hu ) ̅) by up to 25%, but may lead to higher temperatures near the walls. Reducing the distance between the walls of two tubes can slightly increase (h_hd ) ̅, but may also raise wall temperatures. The distance from the tubes to the rectangular heater has minimal effect on h but can lower near-wall temperatures. The addition of PCM can reduce cavity temperatures by only 0.5 to 2 K, as heat transfer is predominantly limited to convection.

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