知識貝殼
知識貝殼
所屬欄目：水輪機與水泵專業英語
This turbine is named after J. B. Francis, an American engineer, who set about to improvethe reaction type of turbines which existed in the year 1849.The original Francis turbine has been modified from time to time to improve itsefficiency, and, today, an ......（本文共 878 字 ） [閱讀本文] >>