熱電除濕器由於具有無噪音、體積精小且無釋放有害氣體污染環境等優點，已被廣泛應用於消費性產品、各式醫療器材及精密儀器。本文針對熱電除濕裝置作熱傳分析，在一定的電功率下以及相同的熱端散熱器下，針對了密閉箱體內部的冷端鰭片做熱質傳的改善。
為了促進除濕效率，首先以自然對流狀況下之推理求得冷端鰭片的最佳化間距，再由實驗來測試冷凝現象時的質傳對除濕效率之影響。由結果顯示質傳所產生之效應可以忽略，而自然對流求得之最佳化間距仍然可以適用於冷端鰭片之吸熱制冷。
此外，在最佳間距的鰭片下試著改變各種參數，如鰭片尺寸、表面材質、位置，以期找出可增加除濕效率的最佳方法。實驗的結果顯示在密閉箱體內部的空氣溫度與鰭片置放位置有較大關連，而冷端鳍片溫度是影響除濕速率最大因素 。當鰭片模組置於箱體上方時，箱體內部溫度比置於側面低5℃；除濕速率越快，但必須避免鰭片表面溫度低於結冰溫度。

Thermoelectric dehumidifier has the advantage, of being quietness, compactness, and free from releasing harmful gases, it is thus widely used in commercial products, medical facilities, and precision instruments. The heat transfer analysis for a thermoelectric dehumidifier is performed in this study. The efforts were focused on improving the heat and mass transfers of cold –end fins inside a cabinet under the same input power and the same hot-end condition.
In order to improve the dehumidification rate, the optimal fin-gap based on the reasoning of pure free convection was calculated and used for testing specimens. Experiments were then conducted to examine the effect of mass transfer during the cooling and condensation processes. Results indicated the effect of mass transfer is negligible and the optimal fin-gap obtained from free convection is still applicable to cold-end fins.
Other tests were also conducted to investigate the effects such as fin geometry, fin-surface condition, the location of fin array inside the cabinet, in order to achieve the best dehumidification rate. The experimental results indicated the internal air temperature of cabinet is most related to the location where thermoelectric module is installed and the dehumidification rate is tightly related to cold-fin temperature. In our testing cases, the internal air temperature can be 5℃ lower when the thermoelectric module is placed on the upper surface instead of side surface, and the dehumidification rate is found faster whenever the cold-end fin is colder. However, the fin temperature should be kept from falling below its freezing point.

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