城市给水工程给水管网设计二方案.docx

城市给水工程给水管网设计二方案1.1管网定线12居民区给水管网系统设计计算1 .3工业区给水管网系统设计计算1.1 管网定线B市分为三个区，其中，I区的房屋层数平均为6层，11区的房屋层数平均为7层，III区的房屋层数平均为8层。并且口、IU区地区的地势较高，所以“、UI区对水压的要求较高，属于高压区；其它地区属于低压区。所以本方案的居民区供水采用并联分区给水系统。各区由同一泵站供给，高压泵将水输送给高压区，低压泵将水输送给低压区，共设置四条输水管，高压泵连两条，低压泵连两条，这样供水比较可靠，而且管理方便。工业区依然另设水源取水，采用树状管网集中供应（同方案一）。1.2 居民区给水管网系统设计计算图LI居民区给水管网示意水厂1的设计规模、居民区用水规律、是否设置水塔的讨论和清水池有效容积的计算这四个步骤同方案一。(1)管网的设计流量管网分为高压区和低压区两个区域，总的设计流量仍以最高日最高时的流量作为设计流量，Qh=2981.3LSo高压区为II、IlI区供水，低压区为I区供水，n、III区共有人口55万人，I区有人口10万人，则高压区供水量约是低压区的1.5倍，所以：高压区供水量：=2522.64L/s低压区供水量：=458.66L/s（2）沿线流量和节点流量的确定表1.1高压区管段长度表管段编号图上距离cm实际长度m配水长度m17.878039029.898049037.979079048.3830415518.41840184069.999099079.494047086.464032097.5750750107.1710710119.99904951211.911901190139.9990990144.7470470156.5650650167.8780390177.2720720186.56506501914.6146014602011.71570785219.4940940227.97907902310.510505252411.511501150252.7270270266.6660660279.29209202810.7107053520755表1.2低压区管段长度表管段编号图上距离cm实际长度m配水长度m2910.11010505309.19104553110.91090545续表1.2管段编号图上距离cm实际长度m配水长度m329.2920920338.28204103412.3123012303513.213201320361.1510255377.2720720384.2420210398.78704354011.611605807585引入长度比流量q,则高压区：q=Ql÷>2522.64÷20755=0.121541.(s.m)(5-1)低压区：q=Q2÷L=458.66÷7585=0.0605L(s.m)(5-2)由此可以算出各个管段的沿线流量:表1.3高压区管段沿线流量管段编号实际长度m配水长度m管段沿线流量1./s178039047.40298049059.56379079096.02483041550.44518401840223.646990990120.33794047057.13864032038.89975075091.161071071086.301199049560.161211901190144.6413990990120.331447047057.131565065079.001678039047.401772072087.511865065079.001914601460177.45续表1.3管段编号实际长度m配水长度m管段沿线流量1./s20157078591.4121940940114.252279079096.0223105052563.812411501150139.782527027032.822666066080.2227920920111.8228107053561.03207552522.64表14低压区管段沿线流量表管段编号实际长度m配水长度m管段沿线流量1./s29101050530.543091045527.5131109054532.963292092051.633382041024.79341230123074.38351320132079.823651025511.423772072043.543842021012.703987043526.3040116058031.077585458.66由于流量变化的管段难以确定管径和水头损失，所以将管段的沿线流量转化为节点流量（以流出节点为正，流入节点为负），则:表1.5高压区节点流节点编号节点设计流量L/s123.702101.49351.004131.275261.57量表节点编 号节点设计流量L/s12117.2913112.7314148.8915127.6216101.79节点编 号节点设计流量L/s6157.10758.648111.479221.82续表1.5节点编 号节点设计流量L/s1786.3018112.4319177.152080.2210171.3811156.79累计2522.64节点编 号节点设计流量L/s2131.752256.842326.152461.3825126.68节点编号节点设计流量L/s2658.662720.862852.462923.89累计458.66表1.6 低压区节点流量表(3)管段水力计算首先，进行管网初分配,即利用最大时用水量对管网进行流量分配，初步确定管段的计算流量，确定管段的管径。将初步确定好的管径、节点流量输入平差软件进行平差，这时管段的流量将会按照管网的水力特性进行分配，其数值并不等于初分配时的流量。具体数据如下表：表1.7高压区管段水力计算结果编号长度直径流量流速单位水总损失头损失mmmLPSm/sm/kmm178030023.700.340.610.48298035069.330.722.102.06379030051.860.792.982.354830450124.330.781.821.515184035049.050.511.102.02699040073.650.591.221.2179403009.950.140.120.118640500180.320.922.171.399750500198.731.012.591.9410710700341.140.901.400.991199060068.590.240.150.15121190600211.340.761.241.481399040032.090.260.260.26续表1.7编号长度直径流量流速单位水头损失总损失mmmLPSm/sm/kmm14470700207.130.540.540.2515650600162.250.570.730.4716780900511.130.800.850.6617720500173.10.882.011.451186501000751.740.961.050.68191460500111.910.570.901.3120157030023.630.330.610.9621940900472.270.740.740.7022790600150.270.530.640.5123105013001096.140.830.580.6124115013001324.721.000.830.952527013001238.420.930.730.20266601000733.090.930.990.65279201000392.910.500.310.29281070500103.850.530.780.8343240013001261.320.950.761.8244240013001261.320.950.761.82表1.8低压区管段水力计算结果长度直径流量流速单位水头损失总损失编号mmmLPSm/sm/kmm29101030044.360