目錄一、水輪機(jī)選型及參數(shù)計(jì)算1.已知參數(shù)………………………12.水輪機(jī)型號(hào)選擇………………13.水輪機(jī)基本參數(shù)計(jì)算…………1二、水輪機(jī)運(yùn)轉(zhuǎn)特性曲線的繪制1.等效率曲線的繪制……………32.等吸出高度線繪制……………43.出力限制線繪制………………5三、蝸殼設(shè)計(jì)1.蝸殼型式及基本參數(shù)的選擇…………………62.進(jìn)口斷面計(jì)算…………………63.圓斷面計(jì)算……………………74.橢圓形斷面計(jì)算………………8四、尾水管設(shè)計(jì)1.尾水管形式的選擇……………92.尾水管高度的確定……………93.尾水管各部分尺寸的計(jì)算……………………9蝸殼平面圖…………10蝸殼單線圖…………11尾水管圖……………12

二、水輪機(jī)運(yùn)轉(zhuǎn)特性曲線的繪制1.等效率曲線的繪制原型水輪機(jī)效率水輪機(jī)出力由附表9（12頁(yè)）查出并計(jì)算出P得到下表H=68mn=69.97r/minH=71.2mn=68.38r/minH=73mn=67.53r/minH=84.5mn=62.77r/minPPPP0.820.8440.6373123.20.6479588.250.6583916.60.68109331.20.840.8640.6779608.740.6886566.370.6991191.610.73120151.50.860.8840.7388745.70.7395082.740.7398711.370.78131352.90.880.9040.7896969.510.77102561.80.77106475.90.84144657.30.90.9240.86109280.50.85115722.40.85120138.70.951672200.90.9241.11141048.11.1149758.41.09154060.20.951672200.880.9041.17145454.31.17155840.71.16160405.21.13194598.50.860.8841.22148314.71.22158905.41.22164969.71.17197029.30.840.8641.261497121.26160402.41.26166523.81.25205738.90.820.8441.3150889.11.31162907.21.31169124.21.29207407.72.等吸出高度線繪制由附表9（12頁(yè)）查出相關(guān)數(shù)據(jù)。根據(jù)各工況點(diǎn)的Hs、P，繪出各水頭下的Hs=f（P）曲線。PH=84.5n=62.770.10.890.9140.8610.14149740.6-0.780.110.90.9240.9710.985170741.3-1.6250.120.880.9091.0311.83177378.4-2.470.130.8850.9091.112.675190481-3.3150.140.8720.8961.1513.52196291.2-4.16H=73n=67.530.10.8940.9180.848.76117954.40.60.110.920.9440.969.49138623-0.130.120.920.9441.0410.22150174.9-0.860.130.8910.9151.1310.95158158.2-1.590.140.8720.8961.1811.68161726.8-2.32H=68n=69.970.10.8910.9150.838.16104441.11.20.110.920.9440.958.84123329.70.520.120.920.9441.049.52135013.6-0.160.130.8950.9191.1310.2142812.5-0.840.140.8730.8971.1910.88146795.1-1.523.出力限制線繪制求出與和相對(duì)應(yīng)的水輪機(jī)出力、，將點(diǎn)（，）、點(diǎn)（、）連成一條斜線，此線即為水輪機(jī)出力限制線。ηQPH=730.9091.1616.13H=680.9141.14714.5

三、蝸殼設(shè)計(jì)1.蝸殼型式及基本參數(shù)的選擇本電站水頭在40m以上，故選用金屬蝸殼，包角選為345°。取，查表得蝸殼流速系數(shù)K=0.87取，，計(jì)算得到，，得，取0.2，計(jì)算得h=0.83m2.進(jìn)口斷面計(jì)算進(jìn)口斷面流量（/s）進(jìn)口斷面流速（m/s）進(jìn)口斷面面積（）進(jìn)口斷面半徑（m）查表得D=7.75，K=0.15（m）進(jìn)口斷面中心距（m）進(jìn)口斷面外徑（m）蝸殼系數(shù)蝸殼常數(shù)3.圓斷面計(jì)算rb13450.724.035.7930.692.2592532.9788.8693.097.0110.123300.694.035.5410.692.2028052.898.3543.016.929.92733150.664.035.2890.692.1448722.8017.8462.926.839.75343000.634.035.0380.692.085332.717.3462.836.749.57552850.594.034.7860.692.0240372.6186.8532.756.659.39462700.564.034.5340.691.9608292.5236.3672.666.559.2172550.534.034.2820.691.8955142.4275.8892.566.469.02282400.54.034.030.691.8278682.3285.4192.476.368.82992250.474.033.7780.691.7576192.2264.9572.386.268.632102100.444.033.5260.691.6844442.1224.5032.286.158.43111950.414.033.2740.691.6079412.0144.0572.186.048.223121800.384.033.0230.691.5276131.9033.622.085.938.008131650.344.032.7710.691.4428181.7873.1921.975.827.787141500.314.032.5190.691.3527191.6652.7731.865.77.556151350.284.032.2670.691.2561751.5372.3641.755.577.315161200.254.032.0150.691.1515641.4021.9641.635.437.06171050.224.031.7630.691.0364481.2551.5761.55.296.7918900.194.031.5110.690.9068351.0941.1981.375.126.4984.橢圓形斷面計(jì)算當(dāng)計(jì)算圓形斷面半徑時(shí)，蝸殼的圓形斷面不能與座環(huán)蝶形邊相切，須由圓斷面過(guò)渡到橢面斷面。圓斷面計(jì)算中，當(dāng)=90時(shí)，，即=90時(shí)，蝸殼形狀已經(jīng)是橢圓形，即應(yīng)按橢圓斷面計(jì)算。橢圓短半徑：與圓的同等面積：橢圓斷面長(zhǎng)半徑,橢圓斷面中心距橢圓斷面外徑計(jì)算結(jié)果如下表1900.18751.3535.96351.401471.294914.90486.30632750.15631.2164.85581.333221.06744.62725.96053600.1251.0683.7981.261460.82824.33545.59694450.09380.9072.79441.185240.574144.02555.21075300.06250.7221.85141.103130.300423.69154.79466150.03130.4950.98011.01284-0.00053.32434.3372蝸殼圖繪制于10、11頁(yè)四、尾水管設(shè)計(jì)1.尾水管形式的選擇大中型反擊式水輪機(jī)組如采用直錐型尾水管，會(huì)帶來(lái)大量的挖深，考慮綜合考慮經(jīng)濟(jì)性等因素，故本方案采用彎肘形尾水管。2.尾水管高度的確定根據(jù)3.尾水管各部分尺寸的計(jì)算查《水電站機(jī)電設(shè)計(jì)手冊(cè)》表2-17得2.64.52.721.351.350.6751.821.22肘管類型