質子交換膜燃料電池(Proton Exchange Membrane Fuel Cell)發電時，質子交換膜含水率對質子的傳遞有很大的影響，進而影響燃料電池的效能。而為了維持薄膜的高含水率，一般都是透過增溼器，在反應氣體通入電池之前，將其相對溼度提高。此外，氫氣相對溼度對於燃料電池性能的影響，遠大於陰極端氣體的相對溼度。
噴霧式增溼器已廣泛應用於燃料電池的增溼。而本實驗使用超音波霧化器，取代傳統的壓力式噴霧器，其好處有體積小，系統簡單，且產生粒徑約10μm。實驗透過改變進氣流量、進氣溫度、增溼器水溫，探討該增溼器在不同條件下的增溼效果。根據實驗結果，該實驗設計的增溼器，改變增溼器水溫，可以有效的控制增溼氣體溫度23~73℃。而當進氣流量15~25 slpm，能提供相對溼度接近飽和(>95%RH)的增溼效果。

The proton conductivity largely depended on the extent of hydration state of the membrane of proton exchange membrane fuel cell(PEMFC), and further affects the fuel cell performance. Typically, sufficient membrane hydration is achieved through the humidification of reactive gases prior to feeding them into the fuel cell. Further, hydrogen humidification has a larger impact on the PEMFC performance than cathode side. Injector humidification has been used to humidify reactive gases. In this study, the experiment used the ultrasonic nebulizer to replace the traditional injector. It has the advantages of small volume, simple system and small droplet production (about 10μm). The study examined the humidifier performance by changing the inlet gas flow rate, inlet gas temperature, and the water temperature in the humidifier. The experimental results showed that changing the water temperature in the humidifier can effectively control the outlet temperature between 23~73℃. The humidifier can supply the near saturated gas (>95%RH) when the inlet gas flow rate between 15~25 slpm.

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