水电站建筑物有压引水水力计算.doc

《水电站建筑物》课程设计有压引水系统水力计算设计计算书姓名专业学号指导教师时间目录第一部分设计课题·······································31.设计内容····································32.设计目的····································3第二部分设计资料及规定································41.设计资料······································42.设计规定······································5第三部分调压井稳定断面计算····························61.引水系统水头损失······························62.引水道有效断面································83.稳定断面计算···································8第四部分调压井水位波动计算····························101.最高涌波水位··································102.最低涌波水位··································13第五部分调节保证计算··································151.水锤计算······································152.转速相对升高值································19第六部分附录···········································211.附图·········································212.参考文献······································21第一部分设计课题1.1课程设计内容对某水电站有压引水系统水力计算1.2课程设计目的通过课程设计进一步巩固所学的理论知识，使理论与工程实际紧密结合。提高学生分析问题和解决实际问题的能力，计算能力和绘图能力。第二部分设计资料及规定2.1设计资料某电站是MT河梯级电站的第四级。坝址以上控制流域面积2362，数年平均流量44.9，由于河流坡降较大，电站采用跨河修建基础拱桥，在桥上再建双曲拱坝的形式，坝高(涉及基础拱桥)54.8m。水库为日调节，校核洪水位1097.35m，相应尾水位1041.32m；正常蓄水位1092.0m，相应尾水位1028.5m；死水位1082.0m，最低尾水位1026.6m。总库容，。装机容量，保证出力，数年平均发电量。该电站引水系统由进水口、隧洞、调压井及压力管道四部分组成，电站平面布置及纵断面图如图所示（指导书图1，图2）隧洞断面采用直径为5.5m的圆形，隧洞末端设一锥形管段，直径由5.5m渐变至5.0m，锥管段长5.0m，下接压力钢管。隧洞底坡取0.005,全长500.3m，其中进水口部分长25.7m,进口转弯段长25.595m,锥管段长为5m。水轮机型号为HL211—LJ—225，阀门从全开到全关的时间为7s，其中有效关闭时间。机组额定转速，飞轮力矩。蜗壳长度，尾水管长度。转轮出口直径。经核算，当上游为正常蓄水位，下游为正常尾水位，三台机满发电，糙率n取平均值，则通过水轮机的流量为96.9，当上游为死水位，下游为正常尾水位，三台机满发，饮水道糙率区最小值，压力管道糙率取最大值，则通过水轮机的流量为102。当上游为校核洪水位,下游为相应尾水位，电站丢弃两台机时，若丢荷幅度为30000—0KW,则流量为63.6—0；丢荷幅度为45000—15000KW,则流量变幅为96.5—31.0。当上游为死水位，下游为正常尾水位时，若增荷幅度为30000—45000KW,则流量变化为68.5—102.5；若丢荷幅度为30000—0KW,则流量变化为67.5—0。采用联合供水方式，两个卜形分岔管布置，主管直径5m，支管直径3.4m,分岔角。从调压井中心至蝴蝶阀中心，全长102.32m。如图4-4可知，压力管道可按钢板、混凝土、围岩联合作用进行结构计算，围岩单位弹性抗力系数为。取压力管道经济流速为，按流量96.9进行计算，压力管道经济直径为5m，蜗壳进口直径为3.4m，故设5m及3.4m两种管径，其中3号压力管道由直径5m过渡到3.4m锥管段长3.789m。三条压力管道中以3号压力管道最长，从隧洞末端到蝴蝶阀中心，全长113.3m。计算时考虑不同的工况，隧洞糙率n分别取0.016，0