溫度與海水流速對陰極保護電流之影響

Abstract

台灣位於季風盛行帶上，四面環海，具有發展離岸風電之潛能，因此台灣近幾年除了其他綠色能源，也開始積極開發海上風場，裝設離岸風機用以取得風能。由於離岸風電位於海洋上，屬於嚴重腐蝕區域，離岸風機在進行設計時亦會考慮防蝕措施。台灣的離岸風電屬於新興產業，相關設計規範主要參考國外之規範。其他國家的規範訂定，應是針對該國環境進行，在經過多年實務經驗後設計出的通則。而台灣未有相關自主設計經驗，且環境與多年發展離岸風電之國家差異甚大，溫度較高且海水流速較快，可能產生更加嚴苛的腐蝕環境，參考他國規範可能有防蝕設計上的不足。因此本論文設計符合台灣海域環境之海水溫度與流速進行陰極防蝕法中的犧牲陽極情境模擬，量測其產生之保護電流量，並根據實驗結果進行擬合，建立能夠預測溫度為15 °C至35 °C且流速為0 m/s至2 m/s條件下保護電流之數學方程式，並根據實驗結果得知溫度與流速提高，皆使電流密度上升，但溫度在高溫時之影響較低溫明顯，而流速則相反。

Since Taiwan is located in a monsoon region, it has potential for developing offshore wind power. In recent years, Taiwan has actively pursued the development of offshore wind energy and has begun generating green energy by installing offshore wind turbines. Due to the highly corrosive condition of the offshore environment, corrosion protection is important. Taiwan's relevant design are mainly based on foreign regulations. However, Taiwan's environment differs from another countries, higher temperature and faster ocean flow velocity potentially creating more severe corrosion conditions than foreign. Relying on foreign standards might result in wrong corrosion protection design. In this thesis, cathodic protection using sacrificial anodes is designed according to Taiwan's ocean temperature and flow velocity, and the protective current is measured. Based on the experimental results, a fitting equation is established to predict the protective current under conditions with temperature ranging from 15 °C to 35 °C and flow velocity ranging from 0 m/s to 2 m/s. The results indicate that if temperature and flow velocity increase, the protective current density will also increase. The influence of higher temperature on protective current density is more significant than that of lower temperature, while flow velocity has the opposite effect.