abrasive material 磨蝕物質(zhì)；研磨材料acidy water 酸性水a(chǎn)cross 穿過；橫穿aggressive 有腐蝕性；侵略性的；好斗的air valve 空氣閥axial bearing 止推軸承axial force 軸向力Bánki-Michell turbine 雙擊式水輪機bearing housing 軸承箱；軸承體behave 表現(xiàn)；運轉(zhuǎn)...[繼續(xù)閱讀]

    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...[繼續(xù)閱讀]

    This is an annular spiral-shaped casing forming the circumference of the turbine. Oneend of it is connected to the penstock to receive the water under pressure from it, and thiswater is admitted uniformly all over the circumference of the runner. The cros...[繼續(xù)閱讀]

    This is a ring with a number of fin-shaped stay vanes welded between two annular rings,as shown in Fig.4.2. The inlet dimensions of the stay vanes are equal to the dimensions of theopening on the inner face of the scroll case. Stay vanes are also termed a...[繼續(xù)閱讀]

    The guide vanes mechanism (Fig.4.3) serves three functions:① To receive water from the stay vanes and direct it at proper angles on the runnervanes so that the shock at the entry of the runner is minimum.② To govern the turbine by controlling the quantity...[繼續(xù)閱讀]

    This is the heart of the turbine. The runner is located between the guide vanes and thedraft tube. Water enters the runner over the entire periphery, imparts most of its energy whiletraveling over the runner vanes and then enters the draft tube.The direct...[繼續(xù)閱讀]

    It is located at the outer of the runner. One end of it is at the runner outlet and the otherend in the tail race. The draft tube serves the following functions:① It carries the water, discharging from the runner, to the tail race.② It creates a negative ...[繼續(xù)閱讀]

    This is a cylindrical box-like structure provided on the top surface of the runner, asshown in Fig.4.7.Fig.4.7 Head cover of a Francis turbineIts functions are ① to prevent any water leaking through the gap between the guidevanes and the runner from findi...[繼續(xù)閱讀]

    This is located at the bottom of the turbine guide vanes between the stay vane ring andthe draft tube, as shown in Fig.4.8. It has an upper annular ring with an external diameterequal to the internal diameter of the stay vanes ring and a lower annular por...[繼續(xù)閱讀]

    The shaft disposition of most of the modern Francis turbines is vertical so that thegenerator can be kept above the highest tail water level. The danger due to flooding can thusbe avoided and the turbine can be kept at another level decided by its design ...[繼續(xù)閱讀]