由於微型熱電致冷晶片擁有冷卻微處理器與其他小型裝置的潛力，而市售常見的熱電致冷晶片則被認為能應用在低溫的廢熱回收上。
因此，為了瞭解熱電致冷晶片的冷卻能力與發電性能，本文先藉由三維數值模擬的方式，分析三種不同尺寸的致冷晶片的冷卻能力，並探討尺度效應與湯姆生效應對於微型致冷晶片的影響。晶片兩端溫差分別設定為0與10K，在晶片內部熱電單元的截面積與長度比例固定的情況下，將其熱電單元的長度由500降至100 μm，因此可得到三種不同尺寸的晶片：內部分別包含8、20與40對的熱電對。模擬結果顯示，當晶片內部熱電單元長度下降、也就是熱電對的數目增加時，晶片的冷卻功率會有明顯的提昇。此外，考慮湯姆生效應（Thomson effect）的影響後，晶片的冷卻功率會提昇約5至7%。
接著，藉由實驗的方式，以不同的鰭片流道、加熱溫度、水流量與晶片串聯數目等操作參數，分析市售常見的熱電致冷晶片應用在廢熱回收上的發電性能。實驗結果顯示，兩種水冷鰭片的內部流道與水流量對於晶片的影響並不大；加熱溫度對於晶片的影響則較為顯著：較高的熱源溫度能夠增加晶片兩端的溫差，使得晶片的輸出功率較大。又由於低水流量的能耗較小，因此建議操作條件為較低的水流量與較高的熱源溫度。此外，晶片串聯數目越多，也能提供較大的輸出功率。然而由於派提爾效應（Peltier effect）以及每片晶片內部材料的不均勻性的影響，晶片多片串聯後，並不能以線性疊加的方式去預測其輸出功率。最後，也在相同的條件下，比較熱電致冷晶片與熱電發電晶片的發電性能，結果發現致冷晶片會比發電晶片更適合應用在溫度低於150 oC的廢熱回收上。

Miniature thermoelectric cooling module (TECM) has been considered as a promising device to achieve effective cooling in microprocessors and other small-scale equipments. Moreover, commercially available TECMs are useful devices to recover low-temperature waste-heat recovery for power generation.
To understand the performances of miniature TECMs, three different modules are analyzed through a three-dimensional numerical simulation. Particular attention is paid to the influence of scaling effect and Thomson effect on the cooling performance. Two different temperature differences of 0 and 10K between the top and the bottom copper interconnectors are taken into account. In addition, three different modules, consisting of 8, 20 and 40 pairs of thermoelectric (TE) element, are investigated where a length of the element decreases from 500 to 100μm with the condition of fixed ratio of cross-sectional area to length. It is observed that when the number of pairs of TE element in a module is increased from 8 to 40, the cooling power of the module grows drastically. The obtained results also suggest that the cooling power of a TECM with Thomson effect can be improved by a factor of 5-7%, and the higher the number of pairs of thermoelectric (TE) element, the better the improvement of the Thomson effect on the cooling power.
Then, to understand the characteristics of power generation from the commercially available TECMs, the performances of the modules at various flow patterns, heating temperatures, flow rates of water and numbers of modules in series are studied experimentally. The results show that the effects of flow pattern of two heat sinks and water flow rate on the performance are not significant, but the heat source plays an important role. Therefore, a lower water flow rate is suggested to save power, whereas a higher hot-side temperature which leads to a larger temperature difference is recommended to give a better performance of the module. Increasing number of modules in series can also provide higher output power. However, the performance of the modules in series cannot be simply predicted using linear superposition due to the Peltier effect and the non-uniformity of every module. The feature of a thermoelectric generator (TEG) is also examined and compared with the TECMs. It is found that TECM is a better choice for power generation from recovering waste heat if the temperature of a system is below 150oC.

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