Hydraulics - All Forums - SWMM 5 or SWMM or EPASWMM and SWMM5 in ICM_SWMM2024-03-28T21:26:55Zhttps://swmm2000.com/forum/topics/feed/category/HydraulicsContinuity error related to pumping and inclusion of on-site pumping measurements to simulationshttps://swmm2000.com/forum/topics/continuity-error-related-to-pumping-and-inclusion-of-on-site-pump2019-02-05T01:50:06.000Z2019-02-05T01:50:06.000ZClaudio Consuegra Martínezhttps://swmm2000.com/members/ClaudioConsuegraMartinez<div><p>Hi all,</p><p>I am reaching out hoping someone can enlighten me with two questions. Thank you all in advance!</p><p>I am currently working at simulating the complete sewer system of a municipality. The system is roughly composed of 100 km of pipes, 13 lifting pump stations (34 pumps) and 1,600 junctions. I am working with PCSWMM (I apologize as I am not using SWMM per se) to set up my DWFs and flow patterns, run and calibrate the model (I have 7 points for calibration purposes). I have likewise set up the calibration for wet conditions and results are fair enough for both cases. Up to hear nothing is out of extraordinary, however, at first, I set the outlet offset of the upstream pipes to the pumping stations to 0 m as no information was known in advance.</p><p>My new model, same conditions as above, includes the offset of the upstream pipes for each pumping station. When I changed this and runt, my model again, the continuity error went from ~ 3% to 7%. I checked my status report and it seems to me that all my instabilities are related to the pumping setup and are located on the junctions right after my pumping stations. I have set the pumping sequences as follows: wet well à pump (Type III) à discharge header à force main à discharge junction. I am not sure why but the vast majority of instabilities are located at the discharge header, <em><u>any ideas of why this is occurring and how to solve it</u></em>? Please note that I have set a pressure head at the discharge header between 70 m to 100 m to account for pressurized flow.</p><p>Part of my troubleshooting has been i) choosing a smaller time step (as small as 2%), ii) dropping the inertial terms of my momentum equation, iii) changing the start-up and shutoff depths for my pumps (Type III) to increase the range over which they work, iv) and letting the time step to be automatically adjusted by 100%. So far, I am getting the best results when using option iii), i.e. by setting my shutoff depth as small as 0.001 m resulting in a continuity error around ~4% (a gain of 3%). Perhaps I am being fussy regarding the continuity error but I really want it to be as small as possible.</p><p>My second question is related to how I am using pumping measurements within my model. Data is available regarding the maximum flow each pump can generate while working alone or in parallel (i.e. pump 1 alone, pump 2 alone and pump 1 and 2 working simultaneously). What I have decided to do, starting at my base model working fine right before including the offset of my upstream pipes, is to set the pump’s maximum flow as the maximum allowable flow in the force main, and to crop my pump curve at the maximum measured flow (sometimes pumps are as old as 25 years or more). I do get the model to reproduce the flows measured on-site, but I am half sure and half not that by doing this I am perhaps inducing an error on how my pumps work (since the flow for a type III pump is a function of the head difference between the inlet and outlet nodes). <em><u>Would you proceed with the modeling this same way?</u></em> Your comments are appreciated!</p><p>Looking forward to hearing ideas and I hope everything is explained in a clear manner.</p><p>Regards,<br/>Claudio</p><p> </p><p> </p></div>Turbulence in simulation resulthttps://swmm2000.com/forum/topics/turbulence-in-simulation-result2015-02-10T16:44:23.000Z2015-02-10T16:44:23.000ZMingkai Zhanghttps://swmm2000.com/members/MingkaiZhang<div><p><span class="font-size-5">Hi, everyone, </span></p><p><span class="font-size-5">I use dynamic wave to simulate a piece of pipe network, and I set up the outfall boundary to time series which I measured several months ago. The outfall boundary is surcharged when it rains. But after the simulation, I find the total inflow of the node nearby the outfall is violent turbulence. I wonder why it is caused and how can it be solved ? </span></p><p><span class="font-size-5"><a href="http://storage.ning.com/topology/rest/1.0/file/get/3284346505?profile=original" target="_self"><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284346505?profile=original" width="703" class="align-full"/></a></span></p><p></p><p><span class="font-size-5">figure 1 the depth of the node nearby the outfall, which is approach the measured value</span><br/><a href="http://storage.ning.com/topology/rest/1.0/file/get/3284346810?profile=original" target="_self"><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284346810?profile=original" width="657" class="align-full"/></a></p><p></p><p></p><p><span class="font-size-5">figure 2 the total inflow of the node in the node nearby the outfall, which is violent turbulence. <a href="http://storage.ning.com/topology/rest/1.0/file/get/3284347086?profile=original" target="_self"><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284347086?profile=original" width="681" class="align-full"/></a></span></p><p></p><p><span class="font-size-5">figure 3 the outfall boundary I set up, which is actual observed value. </span></p><p></p><p><span class="font-size-5">anyone can help ? </span></p><p><span class="font-size-5">thanks a lot . </span></p></div>Problems with SSA version of SWMM computing peak inlet flowshttps://swmm2000.com/forum/topics/problems-with-ssa-version-of-swmm-computing-peak-inlet-flows2014-09-22T23:36:09.000Z2014-09-22T23:36:09.000ZRobert L. Porterhttps://swmm2000.com/members/RobertLPorter<div><p>I am using Autodesk SSA version of SWMM. I am getting unreasonable results that are too high when the inlet is completely submerged by a flow that is say 5 times the inlet capacity. The program appears to calculate the flow in the upstream link based on the depth at the inlet based on an iterative calculation. The peak flow is obviously too high. This flow then continues downstream and makes all the downstream flows too high. However, when I check the Total Inflow on the Time Series Plot, the Total Inflow to the inlet looks about right. Can anyone help me on this? I have also joined the AUTODESK blog and asked the same question. Our company is modeling an entire drainage system for a small town in Colorado.</p></div>Piezometric Head of the Nodes in SWMM 5.https://swmm2000.com/forum/topics/piezometric-head-of-the-nodes-in-swmm-52014-05-05T18:41:59.000Z2014-05-05T18:41:59.000Zkrishnendu pritam debhttps://swmm2000.com/members/krishnendupritamdeb<div><p>How do I get the piezometric head ( pressure + elevation head) of the nodes in the result of SWMM 5? Is there options for this or something has to be implemented in the source code of SWMM5 ? Please throw some light in this regard.</p></div>Flow on LID outputs?https://swmm2000.com/forum/topics/flow-on-lid-outputs2014-04-25T15:28:58.000Z2014-04-25T15:28:58.000ZMenna Yassinhttps://swmm2000.com/members/MennaYassin<div><p>Hello,</p><p>This might be a simple question for some of you but I am still learning the software....</p><p>I am trying to model flow on an LID surface and wanted to ask about the outputs I can get from the software and how I can get it. Is it possible to get the dq at different time intervals? can I get the elevation of water along the x and y axis of the LID surface at a specific time step? Is there a print out or output report that has these detailed information?</p><p></p><p>Thank you for your help!!!</p><p></p></div>Leaping Weir Example in SWMM 5 and InfoSWMM, Alternativehttps://swmm2000.com/forum/topics/6651140:DiscussionEntry:103722013-07-19T18:57:56.000Z2013-07-19T18:57:56.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><div dir="ltr" style="text-align: left;"><b style="font-size: 13px;">Leaping Weir Example in SWMM 5 and InfoSWMM, Alternative</b><br />
<br />
This is an example SWMM 5 model that can be imported into InfoSWMM or H2OMap SWMM using the Exchange/Import Command.   The low flow falls over the berm of the leaping weir into a rectangular open channel but the the "falls" is governed by an OULET Depth/Discharge Type in SWMM 5.  The flow increases in the OUTLET until a depth of 1 feet is reached where the weir starts to operate.  The OUTLET increases in flow from zero to 1 feet but still flows at a reduced rate when the weir starts to operate.  The weir stops flowing when the depth goes below 1 foot on the berm.<br />
<br />
<br />
<table align="center" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;">
<tbody>
<tr>
<td style="text-align: center;"><a href="http://4.bp.blogspot.com/-_WRRkKgYCsg/UemHPqPR44I/AAAAAAAAB8w/AIUeQQtoIvY/s1600/LeapingWeir_2ndWay.png" style="margin-left: auto; margin-right: auto;"><img border="0" height="376" src="http://4.bp.blogspot.com/-_WRRkKgYCsg/UemHPqPR44I/AAAAAAAAB8w/AIUeQQtoIvY/s640/LeapingWeir_2ndWay.png" width="640" /></a></td>
</tr>
<tr>
<td class="tr-caption" style="text-align: center;">Leaping Weir With Low Flow Depth/Discharge OUTLET</td>
</tr>
</tbody>
</table>
</div>
</div>Channel Parameters Sensitivityhttps://swmm2000.com/forum/topics/channel-parameters-sensitivity2013-06-18T02:36:10.000Z2013-06-18T02:36:10.000Zsusantha shameerahttps://swmm2000.com/members/susanthashameera<div><p></p><p>I have develop a event based model to analyze the sensitivity of the channel parameters (Bed and Bank Roughness coefficient, Bed width, Maximum Depth) and the sensitivity of the intermittent storage areas. According to the results, sensitivity values are lesser than 10%. I mean when I change the channel parameters one at a time, plus 50% or minus 50%, model outflow hydrograph peak and the hydrograph shape variation is less than 10%. I used daily resolution rainfall data series. I want to know why there is no significant change when I change those parameters. <a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3284339816?profile=original"></a></p><p></p><p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3284339816?profile=original">N2.ini</a><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3284340246?profile=original">N2.inp</a><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3284340525?profile=original">N2.out</a><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3284340592?profile=original">N2.rpt</a></p><p></p><p>I have attached the model files here.</p><p>Thank you</p></div>How is mass balance calculate in the SWMM when there is system loss (internal outflow)https://swmm2000.com/forum/topics/how-is-mass-balance-calculate-in-the-swmm-when-there-is-system2013-06-13T09:56:49.000Z2013-06-13T09:56:49.000Zsusantha shameerahttps://swmm2000.com/members/susanthashameera<div><p> I used simple schematic to check the mass balance of the model. When I change the channel bed width, outflow hydro-graph peak was reduced but no time lag of the peak. I have found there is a system loss by internal outflow and due to that, I couldn't maintained the mass balance of the event. Can any one let me know how can I change the bed width while keeping the mass balance for the same input rain fall.</p><p>Thank you</p><p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3284339781?profile=original">Capture.JPG</a><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3284339691?profile=original">Capture2.JPG</a></p></div>ponded area in autodesk storm and sanitary system 2012https://swmm2000.com/forum/topics/ponded-area-in-autodesk-storm-and-sanitary-system-20122013-01-16T21:22:27.000Z2013-01-16T21:22:27.000Zyaserthttps://swmm2000.com/members/yasert<div><p>Dear all,</p><p>Have any one worked with autodesk storm and sanitary system 2012?</p><p>I have a question about ponded area in that.</p><p>Does ponded area have a significant effect on calculation process?</p><p>How can I estimate ponded area accurately?</p><p>What will happen if the ponded area would be equal to zero?</p><p>Thanks in advance.</p><p>Yasert</p></div>Various Images from Starts with a Bang re Math and the Environmenthttps://swmm2000.com/forum/topics/various-images-from-starts-with-a-bang-re-math-and-the-environmen2012-11-29T13:26:22.000Z2012-11-29T13:26:22.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><p>Various Images from <a href="http://scienceblogs.com/startswithabang" target="_blank">Starts with a Bang</a>re Math and the Environment</p>
<p></p>
<p>ght now, on Earth, the difference between high and low-tides affects the ocean height by a substantial amount. The Moon (and to a lesser, about 30% effect, the Sun) gravitationally pulls on the Earth slightly more strongly in the direction closest to it, and slightly less strongly in the direction farthest from it.</p>
<div id="attachment_26390" class="wp-caption aligncenter"><a href="http://scienceblogs.com/startswithabang/files/2012/11/tide_force_diagram.gif"><img class="size-full wp-image-26390" title="tide_force_diagram" src="http://scienceblogs.com/startswithabang/files/2012/11/tide_force_diagram.gif" alt="" width="600" height="532" /></a>
<p class="wp-caption-text">Image credit: Department of Oceanography, Naval Postgraduate School.</p>
</div>
<p>This causes the liquid part of the Earth — the oceans — to form two bulges, which are responsible for the high-and-low tides as the Earth rotates. This is why there are two high tides and two low tides each day; each point on the Earth needs to pass through both high points and both low points to make a complete rotation about its axis.</p>
<div id="attachment_26391" class="wp-caption aligncenter"><a href="http://scienceblogs.com/startswithabang/files/2012/11/tumblr_mdo4yt2x2X1r3si8so1_1280.png"><img class="size-medium wp-image-26391" title="tumblr_mdo4yt2x2X1r3si8so1_1280" src="http://scienceblogs.com/startswithabang/files/2012/11/tumblr_mdo4yt2x2X1r3si8so1_1280-600x267.png" alt="" width="600" height="267" /></a>
<p class="wp-caption-text"><span>Image credit: Exploring the Cosmos, via <a class="smarterwiki-linkify" href="http://exploringthecosmos.tumblr.com/">http://exploringthecosmos.tumblr.com/</a>.</span></p>
</div>
<p>With the Moon at our current, 30-Earth-diameter distance, this means that the difference between high tide and low tide can be anywhere from about 5-to-8 feet (1.5 to 2.4 meters), depending on where the Sun, Moon and Earth are relative to one another. (Yes, there are other slight variations to do with latitude etc., but I’m ignoring those.)</p>
<div id="attachment_26392" class="wp-caption aligncenter"><a href="http://scienceblogs.com/startswithabang/files/2012/11/Tide.Bridgeport.png"><img class="size-medium wp-image-26392" title="Tide.Bridgeport" src="http://scienceblogs.com/startswithabang/files/2012/11/Tide.Bridgeport-600x294.png" alt="" width="600" height="294" /></a>
<p class="wp-caption-text">Image credit: Wikipedia user NickyMcLean.</p>
</div>
<p>But if the Moon were just half-the-distance it is to us now?</p>
<p>You might think that the difference between high and low tide would be twice as large. Or, you might remember that Newton’s Law of Gravitation is an inverse-square-law force, and so you might think the tides would be <em>four</em> times as large.</p>
<p>The way tidal forces work, it turns out, means that the tides would be <strong>eight times</strong> as large as they are now, or that each day, the difference between high and low tides would be about <strong>52 feet</strong>, or <strong>16 meters</strong>.</p>
<div id="attachment_26393" class="wp-caption aligncenter"><a href="http://scienceblogs.com/startswithabang/files/2012/11/30980362-tidal-wave.jpeg"><img class="size-medium wp-image-26393" title="30980362-tidal-wave" src="http://scienceblogs.com/startswithabang/files/2012/11/30980362-tidal-wave-600x472.jpg" alt="" width="600" height="472" /></a>
<p class="wp-caption-text">Image credit: user SandyMaiden of allvoices.com.</p>
</div>
<p>In other words, every high tide would bring catastrophic worldwide tidal waves to coastal cities everywhere.</p>
<p>And if the Moon were only one-fourth the distance it is right now, those waves would be <strong>400-footers</strong> instead of 50-footers.</p>
<p>At that point — just under one-fourth the distance — the Moon would pass through geostationary orbit, and would always appear at the same point in the Earth’s sky.</p>
<div id="attachment_26395" class="wp-caption aligncenter"><a href="http://scienceblogs.com/startswithabang/files/2012/11/Geostationary_Sat_fig1.gif"><img class="size-full wp-image-26395" title="Geostationary_Sat_fig1" src="http://scienceblogs.com/startswithabang/files/2012/11/Geostationary_Sat_fig1.gif" alt="" width="600" height="375" /></a>
<p class="wp-caption-text">Image credit: National Space Agency of Japan (NASDA).</p>
</div>
<p>Any closer than that, and the Moon would actually appear to <strong>rise in the West</strong> and <strong>set in the East</strong>, because it would be orbiting the Earth faster than the Earth itself could spin!</p>
</div>Example FM SWMM 5 model with and without Surcharge Depthhttps://swmm2000.com/forum/topics/example-fm-swmm-5-model-with-and-without-surcharge-depth2012-11-10T01:57:49.000Z2012-11-10T01:57:49.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><div class="gmail_quote">
<p><b>Subject:</b>   Example FM SWMM 5 model with and without Surcharge Depth</p>
<p> </p>
<p>You need to use the surcharge depth for a Force Main in SWMM 5 to allow the engine to find the right point on the pump curve and pump up the rising main.  If you do not use a surcharge depth then the flow MAY be very small in the rising main due to a small head difference.  Of course the flow in the force main depends on the pump curve you have entered but having the right downstream head of depth for the link matter as well.  The attached model was created in SWMM 5.0.022 </p>
<p> </p>
<div class="p_embed p_image_embed">
<p><a href="http://getfile7.posterous.com/getfile/files.posterous.com/swmm5/YIuA7cJbxwlQkaRu6bVZrulIEvDe6tSlmq9ib7YBiCBEDeZcq9CblFA9GS2f/image001.png.scaled.1000.jpg"><img alt="Image001" height="539" src="http://getfile7.posterous.com/getfile/files.posterous.com/swmm5/YIuA7cJbxwlQkaRu6bVZrulIEvDe6tSlmq9ib7YBiCBEDeZcq9CblFA9GS2f/image001.png.scaled.1000.jpg" width="1000" /></a></p>
</div>
</div>
<p></p>
<div class="p_embed p_file_embed">
<p><a href="http://swmm5.posterous.com/example-fm-swmm-5-model-with-and-without-surc"><img alt="" src="http://posterous.com/images/filetypes/unknown.png" /></a></p>
<div class="p_embed_description">
<p><strong>fm_storage.inp</strong> <a href="http://getfile1.posterous.com/getfile/files.posterous.com/swmm5/jwbKSHCmfmCfckoDqHfeSKdzjz8HEDsZsjX4pGLiP0jcRDJhnjxKgQqDQpfU/fm_storage.inp">Download this file</a></p>
</div>
</div>
</div>Lead and Lag Pump Options in SWMM 5https://swmm2000.com/forum/topics/lead-and-lag-pump-options-in-swmm-52012-11-10T01:53:47.000Z2012-11-10T01:53:47.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><div><b>Introduction</b>: If you have a <a class="zem_slink" href="http://en.wikipedia.org/wiki/Lead" title="Lead" rel="wikipedia">lead</a> and lag pump connecting the same upstream and downstream nodes the <a class="zem_slink" href="http://en.wikipedia.org/wiki/Normality_%28behavior%29" title="Normality (behavior)" rel="wikipedia">normal behavior</a> for the two pumps is to have the the lead pump turn on first followed by the lag pump. The turn on and turn off depths for the pumps determine when the pumps turn of. The pump will work as a simple lead and lag pump based on a wet well elevation without any <a class="zem_slink" href="http://en.wikipedia.org/wiki/Real-time_computing" title="Real-time computing" rel="wikipedia">real time</a> controls.</div>
<div> </div>
<div>
<p style="text-align: left;"><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284339933?profile=original" alt="" /></p>
<p style="text-align: left;"><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340085?profile=original" alt="" /></p>
<p> </p>
</div>
<div>
<p style="text-align: left;"><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340562?profile=original" alt="" /></p>
<p style="text-align: left;"><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340445?profile=original" alt="" /></p>
<p style="text-align: left;">If you want to add real time controls (RTC) to the lead and lag pumps you can add more sophisticated controls. For example, if you wanted to turn on and off the lead pump at successive time steps then you can add these RTC rules</p>
<p style="text-align: left;">; New Real Time Control (RTC) Rules</p>
<p style="text-align: left;">RULE RULE-1</p>
<p style="text-align: left;">IF PUMP LEAD_PUMP STATUS = ON</p>
<p style="text-align: left;">AND PUMP LAG_PUMP STATUS = ON</p>
<p style="text-align: left;">THEN PUMP LEAD_PUMP STATUS = OFF</p>
<p style="text-align: left;">PRIORITY 1.000000</p>
<p style="text-align: left;">RULE RULE-2</p>
<p style="text-align: left;">IF PUMP LEAD_PUMP STATUS = OFF</p>
<p style="text-align: left;">AND PUMP LAG_PUMP STATUS = ON</p>
<p style="text-align: left;">THEN PUMP LEAD_PUMP STATUS = ON</p>
<p style="text-align: left;">PRIORITY 1.000000</p>
<p style="text-align: left;">RULE RULE-3</p>
<p style="text-align: left;">IF PUMP LEAD_PUMP STATUS = OFF</p>
<p style="text-align: left;">AND PUMP LAG_PUMP STATUS = ON</p>
<p style="text-align: left;">THEN PUMP LEAD_PUMP STATUS = ON</p>
<p style="text-align: left;">PRIORITY 1.000000</p>
<div> </div>
<div><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340809?profile=original" alt="" /></div>
<p> </p>
</div>
<p>If you want to add a pattern of 2 time steps and 1 time step off for both pumps then you can add this RTC new rule to control the lag pump:</p>
<div> </div>
<div>
<div>RULE RULE-4</div>
<div>IF PUMP LEAD_PUMP STATUS = OFF</div>
<div>AND PUMP LAG_PUMP STATUS = ON</div>
<div>THEN PUMP LAG_PUMP STATUS = OFF</div>
<div>PRIORITY 1.000000</div>
<div> </div>
<div>
<p style="text-align: left;"><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284341074?profile=original" alt="" /></p>
</div>
<div class="zemanta-pixie" style="margin-top: 10px; height: 15px;"><a class="zemanta-pixie-a" href="http://reblog.zemanta.com/zemified/c1aa7e8d-53f1-4abf-9263-ba2c993ac3dd/" title="Reblog this post [with Zemanta]"><img class="zemanta-pixie-img" src="http://img.zemanta.com/reblog_e.png?x-id=c1aa7e8d-53f1-4abf-9263-ba2c993ac3dd" alt="Reblog this post [with Zemanta]" style="border: none; float: right;" /></a></div>
</div>
</div>SWMM 5 Leaping Weir Examplehttps://swmm2000.com/forum/topics/6651140:DiscussionEntry:98022012-11-10T01:36:26.000Z2012-11-10T01:36:26.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><div class="gmail_quote">
<p><b>Subject:</b>  SWMM 5 Leaping Weir Example</p>
<p> </p>
<p>The attached example shows one way how SWMM 5 RTC Rules can be used to have the low flow go down a leaping weir orifice and the high flow go over the weir to the downstream section of the sewer. </p>
<p> </p>
<div class="p_embed p_image_embed">
<p><a href="http://getfile6.posterous.com/getfile/files.posterous.com/swmm5/ICmSU7kgyn6l7LlrK8xDN8YglnGCaEs261cj3163ddlBbXBWPJ7mMNDdEshn/image001.png.scaled.1000.jpg"><img alt="Image001" height="533" src="http://getfile6.posterous.com/getfile/files.posterous.com/swmm5/ICmSU7kgyn6l7LlrK8xDN8YglnGCaEs261cj3163ddlBbXBWPJ7mMNDdEshn/image001.png.scaled.1000.jpg" width="1000" /></a></p>
</div>
</div>
<p> </p>
<div class="p_embed p_image_embed"></div>
<div class="p_embed p_file_embed">
<p><a href="http://swmm5.posterous.com/swmm-5-leaping-weir-example"><img alt="" src="http://posterous.com/images/filetypes/unknown.png" /></a></p>
<div class="p_embed_description">
<p><strong>leaping_weir.INP</strong> <a href="http://getfile9.posterous.com/getfile/files.posterous.com/swmm5/S9VBbGMZZFYyR1RbSToBRt8KeSkzf5PNF1sgIeDbKgwxVtq3DmdG4bQ0ws3I/leaping_weir.inp">Download this file</a></p>
</div>
</div>
</div>How are Flooded Time, Surcharged Time and Flooded Volume Calculated in SWMM 5?https://swmm2000.com/forum/topics/how-are-flooded-time-surcharged-time-and-flooded-volume-calculate2012-11-04T17:59:00.000Z2012-11-04T17:59:00.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><div dir="ltr" style="text-align: left;">
<div class="posterous_autopost"><b><span style="font-family: Georgia,serif;">How are Flooded Time, Surcharged Time and Flooded Volume Calculated in SWMM 5?</span></b><br />
<div class="gmail_quote"><br />
<span style="font-family: Georgia,serif;">The time, volume and flooded rate shown in the SWMM 5 Report File Node Flooding Summary (Figure 2) are calculated as follows (Figure 1):</span><br />
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<div style="margin-left: .5in;"><br />
<span style="font-family: Georgia,serif;">For All Nodes NOT Outfalls ( this includes Junctions, Storage Nodes, Dividers)</span></div>
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<div style="margin-left: 1.0in;"><br />
<span style="font-family: Georgia,serif;">If the <span style="color: #c00000;">New Volume is greater than the Full Volume</span> of the or there is Overflow then at each time step the Time Flooded is increased</span></div>
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<div style="margin-left: 1.0in;"><br />
<span style="font-family: Georgia,serif;">If the New Volume is greater than the Full Volume of the or there is Overflow then at each time step the <span style="color: #c00000;">Volume Flooded is increased by the Overflow * Time Step</span></span></div>
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<div style="margin-left: 1.0in;"><br />
<span style="font-family: Georgia,serif;">If the New Volume is greater than the Full Volume of the or there is Overflow AND Surface Ponding is Used then the Ponded Volume is New Volume – Full Volume</span></div>
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<span style="font-family: Georgia,serif;">If the Node Depth Plus the Node Invert Elevation is above the Node Crown Elevation then at each time step the time surcharged is increased.</span><br />
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<td class="tr-caption" style="text-align: center;"><span style="font-family: Georgia, serif; font-size: small; text-align: left;">Figure 1.  Levels of Surcharged and Flooding in SWMM 5.</span></td>
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<td style="text-align: center;"><img alt="Image001" height="363" src="http://getfile1.posterous.com/getfile/files.posterous.com/swmm5/MmYPgAUahuVpz25WoAOwAfkHQZHuKCbCYB16AVGBrffZ6TEEjdCIG3GQUv3k/image001.png" style="margin-left: auto; margin-right: auto;" width="574" /></td>
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<td class="tr-caption" style="text-align: center;"><span style="font-family: Georgia, serif; font-size: small; text-align: left;">Figure 2.  SWMM 5 Node Flooding Summary</span></td>
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</div>How do Weirs Work in SWMM 5?https://swmm2000.com/forum/topics/how-do-weirs-work-in-swmm-52012-11-03T14:26:50.000Z2012-11-03T14:26:50.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><div dir="ltr" style="text-align: left;">
<div class="posterous_autopost"><br />
<b><span style="font-family: Georgia,serif;">How do V-notch weirs work in SWMM 5?</span></b><br />
<div class="gmail_quote"><br />
<span style="font-family: Georgia,serif;">The height of a V-Notch weir is the Height Value in the SWMM 5 Weir Property Dialog (Figure 1) </span><br />
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<span style="font-family: Georgia,serif;">The Length in the Dialog for a V-Notch is the Top Width of Triangular Shaped V-Notch Weir. </span><br />
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<span style="font-family: Georgia,serif;">The slope of the sides of the V-Notch Weir is Square Root (1 + Top Width / Height / 2 * Top Width / Height / 2)</span><br />
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<span style="font-family: Georgia,serif;">The full area is the Height * Height * Side Slope</span><br />
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<span style="font-family: Georgia,serif;">The hydraulic radius is the Height / ( 2 * Height * Side Slope)</span><br />
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<span style="font-family: Georgia,serif;">The two values Height and Length for a SWMM 5 V-Notch Weir determines the area, hydraulic radius and side slope of the weir.</span><br />
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<td style="text-align: center;"><img alt="Image002" height="368" src="http://getfile2.posterous.com/getfile/files.posterous.com/swmm5/rnl2wYy43yWEHl9Mp15FrpEg9RhoV40ztFpQdnM93pomHuVahEcyhfu3dFGn/image002.png" style="margin-left: auto; margin-right: auto;" width="462" /></td>
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<td class="tr-caption" style="text-align: center;"><b style="font-size: medium; text-align: left;"><span style="font-family: Georgia,serif;">Figure 1.</span></b><span style="font-family: Georgia,serif; font-size: small; text-align: left;">   Parameters for a V-Notch Weir in SWMM 5</span></td>
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</div>Spatial Step in a SWMM 5 Linkhttps://swmm2000.com/forum/topics/spatial-step-in-a-swmm-5-link2012-10-31T17:26:57.000Z2012-10-31T17:26:57.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><div dir="ltr" style="text-align: left;"><br />
<a class="zem_slink" href="http://en.wikipedia.org/wiki/Storm_Water_Management_Model" rel="wikipedia" title="Storm Water Management Model">SWMM</a> 3,4,5 uses a spatial step equal to the length of the <a class="zem_slink" href="http://en.wikipedia.org/wiki/Link" rel="wikipedia" title="Link">link.</a> Or, in terms of the 1D St. Venant Equation for the calculation of flow used in SWMM 5:<br />
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<img src="http://storage.ning.com/topology/rest/1.0/file/get/3284339976?profile=original" style="height: 95px; width: 395px;" /><br />
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In which <img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340228?profile=original" style="height: 25px; width: 26px;" />is the length of the conduit.<br />
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The program will calculate the <a class="zem_slink" href="http://en.wikipedia.org/wiki/Cross-sectional_data" rel="wikipedia" title="Cross-sectional data">cross sectional</a> area, <a class="zem_slink" href="http://en.wikipedia.org/wiki/Manning_formula" rel="wikipedia" title="Manning formula">hydraulic radius</a> top width and depth at the upstream, midpoint and downstream sections of the link. The link solution is pivoted on the midpoint <a class="zem_slink" href="http://en.wikipedia.org/wiki/Area" rel="wikipedia" title="Area">cross sectional area</a> in the dominant dynamic wave terms <img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340296?profile=original" style="height: 41px; width: 93px;" />and <img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340581?profile=original" style="height: 27px; width: 90px;" /><br />
<br />
and the non-linear term in the dynamic <a class="zem_slink" href="http://en.wikipedia.org/wiki/Wave_equation" rel="wikipedia" title="Wave equation">wave equation</a> <img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340728?profile=original" style="height: 62px; width: 46px;" />uses the <a class="zem_slink" href="http://en.wikipedia.org/wiki/Upstream_and_downstream_%28DNA%29" rel="wikipedia" title="Upstream and downstream (DNA)">upstream and downstream</a> link cross sectional areas. In the <a class="zem_slink" href="http://en.wikipedia.org/wiki/Finite_difference" rel="wikipedia" title="Finite difference">finite difference equation</a> in SWMM 5 the pipe shown below would have one length but use the cross sectional information from the upstream, midpoint and downstream points of the link.<br />
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The bend in the pipe would be modeled using the "other" category of losses<br />
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<img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340915?profile=original" style="height: 68px; width: 85px;" /><br />
<img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340941?profile=original" /><br />
<div class="zemanta-pixie" style="height: 15px; margin-top: 10px;"><br />
<a class="zemanta-pixie-a" href="http://reblog.zemanta.com/zemified/03aa95aa-1f0c-4c69-b56d-cd411839291e/" title="Zemified by Zemanta"><img alt="Zemanta Pixie" class="zemanta-pixie-img" src="http://img.zemanta.com/reblog_e.png?x-id=03aa95aa-1f0c-4c69-b56d-cd411839291e" style="float: right;" /></a></div>
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</div>SWMM 5 Control Rules for Pumpshttps://swmm2000.com/forum/topics/swmm-5-control-rules-for-pumps2012-10-10T01:43:18.000Z2012-10-10T01:43:18.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><div dir="ltr" style="text-align: left;">
<div class="posterous_autopost"><br />
<b>Subject:</b>  SWMM 5 Control Rules for Pumps<br />
<div class="gmail_quote"><br />
If you want to define the setting for a pump between the Pump On and Pump Off depths then an IF statement based on the Pump flow will work better as in this example, which changes the setting for the pump between a depth of 18 and 20 meters.   The IF statement based on flow will ensure the rule only applies when the Pump Control depth is moving from the Pump On depth to the Pump Off depth and NOT between the Pump Off and Pump On depth.  Figure 1 shows how the Pump Flow is related to the Pump Setting.<br />
<br />
<b>RULE CONTROL_Rule2</b><br />
<b>IF PUMP PUMP1 FLOW > 0.000000</b><br />
<b>AND NODE WELL HEAD > 18.000000</b><br />
<b>AND NODE WELL HEAD < 20.000000</b><br />
<b>THEN PUMP PUMP1 SETTING = 0.700000</b><br />
<b>PRIORITY 2.000000</b><br />
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<td class="tr-caption" style="text-align: center;"><b style="font-size: medium; text-align: left;">Figure 1</b><span style="font-size: small; text-align: left;">   Pump Flow is related to the Pump Setting</span></td>
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</div>Lambda Calculus and Link Variables in the InfoSWMM, H2OMAP SWMM and SWMM 5 Dynamic Wave Solutionhttps://swmm2000.com/forum/topics/lambda-calculus-and-link-variables-in-the-infoswmm-h2omap-swmm-an2012-10-06T12:06:35.000Z2012-10-06T12:06:35.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><div dir="ltr" style="text-align: left;">
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<span style="font-family: georgia, palatino;"><b>Subject:</b>  <b>Lambda Calculus and Link Variables in the InfoSWMM, H2OMAP SWMM and SWMM 5 Dynamic Wave Solution</b></span></div>
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<div style="font-size: medium; margin: 0px;"><span style="font-family: georgia, palatino;">SWMM 5 uses the method of Successive under-relaxation to solve the <b>Node Continuity Equation</b> and the <b>Link Momentum/Continuity Equation</b> for a time step.  The dynamic wave solution in dynwave.c will use up to 8 iterations to reach convergence before moving onto the next time step.  The differences between the link flows and node depths are typically small (in a non pumping system) and normally converge within a few iterations unless you are using too large a time step.  The number of iterations is a minimum of two with the 1<sup>st</sup> iteration NOT using the under-relaxation parameter omega. The solution method can be term successive approximation, fixed iteration or Picard Iteration, <em><i>fixed</i></em>-<em><i>point combinatory, iterated function and </i></em><b>Lambda Calculus</b>. In <a href="http://en.wikipedia.org/wiki/Computer_science" title="Computer science">computer science</a>, iterated functions occur as a special case of <a href="http://en.wikipedia.org/wiki/Recursion_(computer_science)" title="Recursion (computer science)">recursive functions</a>, which in turn anchor the study of such broad topics as <a href="http://en.wikipedia.org/wiki/Lambda_calculus" title="Lambda calculus">lambda calculus</a>, or narrower ones, such as the <a href="http://en.wikipedia.org/wiki/Denotational_semantics" title="Denotational semantics">denotational</a> semantics  of computer programs (<a href="http://en.wikipedia.org/wiki/Iterated_function">http://en.wikipedia.org/wiki/Iterated_function</a>). </span></div>
<div style="font-size: medium; margin: 0px;"><span style="font-family: georgia, palatino;"> </span></div>
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<span style="font-family: georgia, palatino;">In the SWMM 5 application of this various named iteration process there are three main concepts for starting, iterating and stopping the iteration process during one time step:</span></div>
<div style="font-size: medium; margin: 0px;"><span style="font-family: georgia, palatino;"> </span></div>
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<span style="font-family: georgia, palatino;">·         The 1<sup>st</sup> guess of the new node depth or link flow is the current link flow (Figure 3) and the new estimated node depths and link flows are used at each iteration to estimate the new time step depth or flow.  For example, in the node depth (H) equation dH/dt = dQ/A the value of dQ or the change in flow and the value of A or Area is updated at each iteration based on the last iteration’s value of all node depths and link flows.  </span></div>
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<div style="font-size: medium; margin: 0px;"><span style="font-family: georgia, palatino;">·         A bound or a bracket on each node depth or link flow iteration value is used by averaging the last iteration value with the new iteration value.  This places a boundary on how fast a node depth or link flow can change per iteration – it is always ½ of the change during the iteration (Figure 1).  </span></div>
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<span style="font-family: georgia, palatino;">·         The Stopping Tolerance (Figure 2) determines how many iterations it takes to reach convergence and move out of the iteration process for this time step to the next time step.</span></div>
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<td style="text-align: center;"><span style="font-family: georgia, palatino;"><img alt="Image005" height="184" src="http://getfile1.posterous.com/getfile/files.posterous.com/swmm5/ZsTRBlQxXONuCDWMlrZ3oHqrfRIEPmxiL7gupPstjDDMbZKyfsRYynpwAJK3/image005.png" style="margin-left: auto; margin-right: auto;" width="504" /></span></td>
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<td class="tr-caption" style="text-align: center;"><span style="font-family: georgia, palatino;"><b style="font-family: Georgia, 'Times New Roman', serif; font-size: medium; text-align: left;">Figure 1.</b><span style="font-size: small; text-align: left;">  Under relaxation with an omega value of ½ is done on iterations 2 through a possible 8 in SWMM 5. This is </span><b style="font-family: Georgia, 'Times New Roman', serif; font-size: medium; text-align: left;">not</b><span style="font-size: small; text-align: left;"> done for iteration 1.</span></span></td>
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<td style="text-align: center;"><span style="font-family: georgia, palatino;"><img alt="Image008" height="184" src="http://getfile1.posterous.com/getfile/files.posterous.com/swmm5/S8pY30kKXEhiTSk8ZoRC5GQDzqrKRA1kl6pRxDV0ruAskWpgNxyg2s3x3ver/image008.png" style="margin-left: auto; margin-right: auto;" width="505" /></span></td>
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<td class="tr-caption" style="text-align: center;"><span style="font-family: georgia, palatino;"><b style="font-family: Georgia, 'Times New Roman', serif; font-size: medium; text-align: left;">Figure 2.</b><span style="font-size: small; text-align: left;">  if the change in the Node Depth is less than the stopping tolerance in SWMM 5 the node is considered converged.  The stopping tolerance has a default value of 0.005 feet in SWMM 5.0.022. </span></span></td>
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<td style="text-align: center;"><span style="font-family: georgia, palatino;"><img alt="Image002" src="http://getfile0.posterous.com/getfile/files.posterous.com/swmm5/27l83SZeudhXUIlyjJ9x1z5PesrBjg07gigfSlgwR7ndmGjAJQdMHXdodbkk/image002.png.scaled.1000.jpg" style="margin-left: auto; margin-right: auto;" /></span></td>
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<td class="tr-caption" style="text-align: center;"><span style="font-family: georgia, palatino;"><b style="font-family: Georgia, 'Times New Roman', serif; font-size: medium; text-align: left;">Figure 3.</b><span style="font-size: small; text-align: left;">  The differences between the link flows and node depths are typically small (in a non pumping system) and normally converge within a few iterations unless you are using too large a time step.  The number of iterations is a minimum of two with the 1</span><sup style="font-family: Georgia, 'Times New Roman', serif; text-align: left;">st</sup><span style="font-size: small; text-align: left;"> iteration NOT using the under-relaxation parameter omega.</span></span></td>
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<span style="font-family: georgia, palatino;"><a href="http://getfile0.posterous.com/getfile/files.posterous.com/swmm5/27l83SZeudhXUIlyjJ9x1z5PesrBjg07gigfSlgwR7ndmGjAJQdMHXdodbkk/image002.png.scaled.1000.jpg"></a></span></div>
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<span style="font-family: georgia, palatino;"><b>St. Venant equation</b> – this is the link attribute data used when the St. Venant Equation is used inSWMM 5, H2OMAP SWMM and InfoSWMM.  Simulated Parameters from the upstream, midpoint and downstream sections of the link are used.</span></div>
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<td style="text-align: center;"><span style="font-family: georgia, palatino;"><img alt="Image004" height="557.565789473684" src="http://posterous.com/getfile/files.posterous.com/swmm5/D12vxbz3sC1zLxUQnSQ5KYTC4xZwGKEsy9ZSufORE8ClgNt5RJgYJfRitIP6/image004.png" style="margin-left: auto; margin-right: auto;" width="600" /></span></td>
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<td class="tr-caption" style="text-align: center;"><span style="font-family: georgia, palatino;"><b style="font-family: Georgia, 'Times New Roman', serif; font-size: medium; text-align: left;">Figure 4.</b><span style="font-size: small; text-align: left;">  Variables Used in the St Venant Equation if used in SWMM 5.</span></span></td>
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<span style="font-family: georgia, palatino;"><a href="http://posterous.com/getfile/files.posterous.com/swmm5/D12vxbz3sC1zLxUQnSQ5KYTC4xZwGKEsy9ZSufORE8ClgNt5RJgYJfRitIP6/image004.png"></a></span></div>
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<span style="font-family: georgia, palatino;"><b>Normal Flow Equation</b> – this is the link attribute data used when the Normal Flow Equation is used in H2OMAP SWMM. Only simulated parameters from the upstream end of the link are used if the normal flow equation is used for the time step.  The normal flow equation is used if the flow is supercritical or the water surface slope is less than the bed slope of the link.</span></div>
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<td style="text-align: center;"><span style="font-family: georgia, palatino;"><img alt="Image006" height="552.631578947368" src="http://posterous.com/getfile/files.posterous.com/swmm5/c3x3607uh3DggE6uzejjDsSSNhE6QN06y7spWzUks5hhXNhASEqQPvkhwQJj/image006.png" style="margin-left: auto; margin-right: auto;" width="600" /></span></td>
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<td class="tr-caption" style="text-align: center;"><span style="font-family: georgia, palatino;"><b style="font-family: Georgia, 'Times New Roman', serif; font-size: medium; text-align: left;">Figure 5.</b><span style="font-size: small; text-align: left;">  Variables Used in the Normal Flow Equation if used in SWMM 5.</span></span></td>
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<span style="font-family: georgia, palatino;"><a href="http://posterous.com/getfile/files.posterous.com/swmm5/c3x3607uh3DggE6uzejjDsSSNhE6QN06y7spWzUks5hhXNhASEqQPvkhwQJj/image006.png"></a></span></div>
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</div>Pumpshttps://swmm2000.com/forum/topics/pumps2012-09-03T22:21:12.000Z2012-09-03T22:21:12.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><div dir="ltr" style="text-align: left;">
<div class="posterous_autopost"><br />
<b><span style="font-family: Georgia,serif;">Subject:</span></b><span style="font-family: Georgia,serif;">   Reasons A Pump H-Q Curve may be Different than the Design Curve</span><br />
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<span style="font-family: Georgia,serif;">From Allan R. Budris and <a href="http://www.waterworld.com/articles/print/volume-27/issue-6/departments/pump-tips-techniques/how-to-avoid-replacement-pumps-not-meeting-expectations.html" target="_blank">Water World</a></span><br />
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<strong><span style="font-family: Georgia,serif; font-size: 11.0pt;">Actual system H-Q curve not known:</span></strong></div>
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<span style="font-family: Georgia,serif; font-size: 11.0pt;">The actual current system H-Q curve may be different than the original system design. Once a plant is commissioned and the plant is put in service, the system head begins to change. In the short term, levels change in the tanks and wells, valves open and close, and filter screens become clogged. As maintenance occurs, pipe schedules are changed, equipment is changed and new equipment is added into the system. In the long term, equipment loses efficiency, scale forms on the internal pipe walls and the plant undergoes expansion and contraction. Even when new, the original calculated system curve may differ from the actual system performance due to the assumptions used in the calculation, such as 10 year old pipe. Any pump change should, therefore, start with the development (confirmation) of the true current pumping system “Head-Capacity” curve, as detailed in the writer’s January 2009 Column on: “Creating an Accurate Pumping System Head-Capacity Curve...“ A field test of the pump total developed head at one or more measured flow rates can help determine the actual (current) pump and system H-Q curves. By developing the true system head-capacity curve, an accurate determination of the current and new pump operating conditions can be established.</span></div>
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<span style="font-family: Georgia,serif; font-size: 11.0pt;">Additional references on aging pumps</span></div>
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<span style="font-family: Georgia,serif; font-size: 11.0pt;"><a href="http://www.baltimoreaircoil.com/english/resource-library/file/552" target="_blank">Cooling Pumps and Towers</a></span></div>
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<span style="font-family: Georgia,serif; font-size: 11.0pt;"><a href="http://www.pumped101.com/pm%20part%201.pdf" target="_blank">Two Steps to a Longer Pump Life</a></span></div>
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<span style="font-family: Georgia,serif; font-size: 11.0pt;"><a href="http://203.158.253.140/media/e-Book/Engineer/Hydraulic%20and%20Pneumatic/Hydraulic%20Design%20Handbook/0071449590_ar010.pdf" target="_blank">Pump System Hydraulic Design</a></span></div>
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<span style="font-family: Georgia,serif; font-size: 11.0pt;">From Pump System Hydraulic Design <b>10.2.4 Determination of Pump Operating Points—Single Pump</b></span></div>
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<span style="font-family: Georgia,serif; font-size: 11.0pt;">The system curve is superimposed over the pump curve; (Fig. 10.6). The pump operating points occur at the intersections of the system curves with the pump curves. It should be observed that the operating point will change with time. As the piping ages and becomes rougher, the system curve will become steeper, and the intersecting point with the pump curve will move to the left. Also, as the impeller wears, the pump curve moves downward. Thus, over a period of time, the output capacity of a pump can decrease significantly. See Fig. 10.7. for a visual depiction of these combined effects</span></div>
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</div>pump behaviorhttps://swmm2000.com/forum/topics/pump-behavior2012-08-08T06:32:51.000Z2012-08-08T06:32:51.000ZHugh Williamshttps://swmm2000.com/members/HughWilliams<div><p>Hi</p><p>I've set up a pretty straight forward model that involves a storage node with a pump deilvering to a force main which discharges to a gravity main. Gravity main has an orifice at the end to deliver about 60l/s. Pump cut in at 2.1 depth cutout at 1.5. Preliminary numbers on the pump done manually suggest a duty of about <a rel="nofollow" href="mailto:110l/s@10m">110l/s@10m</a>. Baseflow into the storage node is set at 67l/s ie pump should cycle and therefore the gravity main should empy also. The results however dont show this as the gravity line fills but never empties.</p><p> </p><p>Help please!</p><p> </p><p> </p><p> </p><p> </p></div>What are the Types of Force Mains (FM) in SWMM 5?https://swmm2000.com/forum/topics/what-are-the-types-of-force-mains-fm-in-swmm-52012-07-21T14:14:04.000Z2012-07-21T14:14:04.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><p><b><font face="Georgia, serif">Subject:</font></b><font face="Georgia, serif">   What are the Types of Force Mains (FM) in SWMM 5?</font></p>
<p><b><font face="Georgia, serif"> </font></b></p>
<p><font face="Georgia, serif">There are five ways to model a force main in SWMM 5 for the combination of full and partial flow in the force main (Figure 1):</font></p>
<p><font face="Georgia, serif"> </font></p>
<p><font face="Georgia, serif"><font>1.<font face="'Times New Roman'">       </font></font></font><font face="Georgia, serif">Full Flow using Darcy-Weisbach for the friction loss</font></p>
<p><font face="Georgia, serif"><font>2.<font face="'Times New Roman'">      </font></font></font><font face="Georgia, serif">Full Flow using Hazen-Williams for the friction loss</font></p>
<p><font face="Georgia, serif"><font>3.<font face="'Times New Roman'">      </font></font></font><font face="Georgia, serif">Full Flow using Manning’s n for the friction loss</font></p>
<p><font face="Georgia, serif"><font>4.<font face="'Times New Roman'">      </font></font></font><font face="Georgia, serif">Partial Flow uses Manning’s n for the friction loss for Force Main Equation options</font></p>
<p><font face="Georgia, serif"> </font></p>
<p><font face="Georgia, serif">If you use Darcy-Weisbach or Hazen-Williams then<b> </b>an equivalent Manning's n for a force main that results in the same normal flow value for a force main flowing full under fully turbulent conditions is calculated internally in SWMM 5 in forcemain.c</font></p>
<p><font face="Georgia, serif"> </font></p>
<p><font face="Symbol"><font>·<font face="'Times New Roman'">         </font></font></font><font face="Georgia, serif">Equivalent n for H-W is 1.067 / Hazen-Williams Coefficient  * (Full Depth / Bed Slope) ^ 0.04</font></p>
<p><font face="Georgia, serif"> </font></p>
<p><font face="Symbol"><font>·<font face="'Times New Roman'">         </font></font></font><font face="Georgia, serif">Equivalent n for D-W is (<b>Darcy-Weisbach friction factor</b>/185) * (Full Depth) ^ 1/6</font></p>
<p><font face="Georgia, serif"> </font></p>
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<td class="tr-caption"><b><font face="Georgia, serif">Figure 1.</font></b><font face="Georgia, serif">  Types of Full and Partially Full Force Mains in SWMM 5</font></td>
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</div>Types of Stormwater Inlets from HEC-12 and HEC-22https://swmm2000.com/forum/topics/types-of-stormwater-inlets-from-hec-12-and-hec-222012-07-15T16:49:49.000Z2012-07-15T16:49:49.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><div class="gmail_quote">
<p><font face="Verdana, sans-serif">Note:  Types of Stormwater Inlets from HEC-12 and HEC-22</font></p>
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<p><font face="Verdana, sans-serif">Stormwater Inlets consist of four main types (</font><font face="Verdana, sans-serif"><a href="http://onlinemanuals.txdot.gov/txdotmanuals/hyd/storm_drain_inlets.htm" target="_blank">http://onlinemanuals.txdot.gov/txdotmanuals/hyd/storm_drain_inlets.htm</a>) with most common shown in Figure 1.</font></p>
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<p><font face="Verdana, sans-serif">1.<font face="'Times New Roman'">   </font></font><font face="Verdana, sans-serif">Curb opening inlets either at a sag or continuous on the street,</font></p>
<p><font face="Verdana, sans-serif">2.<font face="'Times New Roman'">   </font></font><font face="Verdana, sans-serif">Grate Inlets either at a sag or in combination with a Curb opening</font></p>
<p><font face="Verdana, sans-serif">3.<font face="'Times New Roman'">   </font></font><font face="Verdana, sans-serif">Slotted Drains in parking lots which can be simulated as curb opening inlets and</font></p>
<p><font face="Verdana, sans-serif">4.<font face="'Times New Roman'">   </font></font><font face="Verdana, sans-serif">Combination inlets either at a sag or continuous on the street which combine a curb opening inlet and a grate inlet for the stormwater runoff</font></p>
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<p><font face="Verdana, sans-serif">A sag inlet is the end of the line for the runoff because the flow and its debris load have no other place to go as described in the <a href="http://www.fhwa.dot.gov/engineering/hydraulics/pubs/10009/10009.pdf" target="_blank">HEC-22</a> and <a href="http://www.fhwa.dot.gov/bridge/hec12.pdf" target="_blank">HEC-12</a> manuals and a continuous grade inlet is designed to capture the entire runoff flow but if the flow is too large or the inlet is clogged the bypassed flow can travel past the inlet and flow on down the street to a new inlet.   The interception of a sag inlet is ultimately 100 percent but the amount of interception by a continous inlet is variable and is governed by the width of the opening, the grade of the street, the splash over velocity and the amount of side and flontal flow in a grated or combination inlet which is governed by the width and the length of the grate.  Any flow in a continous opening inlet that is not captured ends up as bypass flow and travels down the downstream link or conduit (Figure’s 2, 3, 4, 5 and 6).</font></p>
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<p><b><font face="Verdana, sans-serif">Figure 1.</font></b><font face="Verdana, sans-serif">  Common Types of Stormwater Inlets on Streets</font></p>
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<p><img alt="Image003" height="563" src="http://getfile6.posterous.com/getfile/files.posterous.com/swmm5/4NiUbxCF7ximDMWc08th3hpwXHX0DvA6HAKkvPZQbkpRqaH9MZ021DHQUKhI/image003.gif" width="500" /></p>
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<p><b><font face="Verdana, sans-serif">Figure 2.</font></b><font face="Verdana, sans-serif" size="3">  Continuous Grate Inlet(1) and Sag Curb Opening Inlet(4)</font> </p>
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<p><b><font face="Verdana, sans-serif">Figure 3.</font></b><font face="Verdana, sans-serif" size="3">  Curb Opening Inlets(2)</font></p>
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<p><b><font face="Verdana, sans-serif">Figure 4.</font></b><font face="Verdana, sans-serif" size="3">  Continuous Curb Opening Inlet(2)</font></p>
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<p><b><font face="Verdana, sans-serif">Figure 5:</font></b><font face="Verdana, sans-serif" size="3"> Grate Inlets and Combination Inlets (1, 3 and 5)</font> </p>
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<p><b><font face="Verdana, sans-serif">Figure 6:</font></b><font face="Verdana, sans-serif" size="3"> Grate Inlets and Combination Inlets (1, 3 and 5)</font> </p>
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</div>How is the St Venant Equation Solved for in the Dynamic Wave Solution of SWMM 5?https://swmm2000.com/forum/topics/how-is-the-st-venant-equation-solved-for-in-the-dynamic-wave-solu2012-05-26T22:12:09.000Z2012-05-26T22:12:09.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><p><b><font>Subject:   </font></b><font>How is the St Venant Equation Solved for in the Dynamic Wave Solution of SWMM 5?</font></p>
<p><b><font> </font></b></p>
<p><font>An explanation of the four St. Venant Terms in SWMM 5 and how they change for Gravity Mains and Force Mains. The HGL is the water surface elevation in the upstream and downstream nodes of the link. The HGL for a full link goes from the pipe crown elevation up to the rim elevation of the node + the surcharge depth of the node.  The four terms are:</font></p>
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<p><b><font>dq2</font></b><font><font> </font></font><font>= Time Step * Awtd * (Head Downstream – Head Upstream) / Link Length or</font></p>
<p><b><font>dq2</font></b><font><font> </font></font><font>= Time Step * Awtd * (<b>HGL</b>) / Link Length</font></p>
<p><b><font>Qnew</font></b><font><font> </font></font><font>= (Qold – dq2 + dq3 + dq4) / ( 1 + dq1)</font></p>
<p><font>when the force main is full dq3 and dq4 are zero and</font></p>
<p><b><font>Qnew</font></b><font><font> </font></font><font>= (Qold – dq2) / ( 1 + dq1)</font></p>
<p><font>The<font> </font><b>dq4</b><font> </font>term in dynamic.c uses the area upstream (<b>a1</b>) and area downstream (<b>a2</b>), the midpoint velocity, the sigma factor (a function of the link Froude number), the link length and the time step or</font></p>
<p><b><font>dq4<font> </font></font></b><font>= Time Step * Velocity * Velocity * (a2 – a1) / Link Length * Sigma</font></p>
<p><font>the dq3 term in dynamic.c uses the current midpoint area (a function of the midpoint depth), the sigma factor and the midpoint velocity</font></p>
<p><b><font>dq3</font></b><font><font> </font></font><font>= 2 * Velocity * ( Amid(current iteration) – Amid (last time step) * Sigma</font></p>
<p><b><font>dq1</font></b><font><font> </font></font><font>= Time Step * RoughFactor / Rwtd^1.333 * |Velocity|</font></p>
<p><font>The weighted area (<b>Awtd</b>) is used in the dq2 term of the St. Venant equation:</font></p>
<p><b><font>dq2</font></b><font><font> </font></font><font>= Time Step * Awtd * (Head Downstream – Head Upstream) / Link Length</font></p>
<p><font> </font></p>
<p><font>The four terms change at each iteration and time step to determine the new flow (Figure 1) based on the two equations:</font></p>
<p><font> </font></p>
<p><font>Denom = 1 + dq1 + dq5</font></p>
<p><font>Q = [Qold – dq2 + dq3 + dq4] / Denom</font></p>
<p><font> </font></p>
<p><font>If you look at a table of the values you will see that the terms add up to zero when the flow is constant and to delta Q or the change in Q when the flow is NOT constant (Figure 2).</font></p>
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<p><b><font>Figure 1.</font></b><font>  The four terms define the new flow at each iteration in the dynamic wave solution of SWMM5</font></p>
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<p><b><font>Figure 2. </font></b><font>  The magnitude of the four terms determine the flow at the new iteration and ultimately the new Time Step.  If the flow is constant then the value of the term is constant.</font></p>
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<p><a href="http://getfile8.posterous.com/getfile/files.posterous.com/swmm5/xUnVRbilgzRWW0TD9GrdO3BefaHlaLyzC4aqs3J7QIGvboLPes4fBZgoeZJE/image001.png.scaled.1000.jpg"><img alt="Image001" height="541" src="http://getfile8.posterous.com/getfile/files.posterous.com/swmm5/xUnVRbilgzRWW0TD9GrdO3BefaHlaLyzC4aqs3J7QIGvboLPes4fBZgoeZJE/image001.png.scaled.1000.jpg" width="1000" /></a></p>
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</div>Forced mainhttps://swmm2000.com/forum/topics/forced-main2012-04-30T07:51:18.000Z2012-04-30T07:51:18.000ZVasenjkahttps://swmm2000.com/members/Vasenjka<div><p>Hello!</p><p></p><p>I am trying to model system:</p><p></p><p>Storage unit (el 100.00), pump, and then forced main and then some outlet (el 104.00) where pipeline connects on gravity sewer system. Slope is always adverse so I am using Dynamic wave.</p><p></p><p>I started with storage unit, then with pump and then with nodes-forced main-nodes etc until node-force main-outlet. But, it doesn't work, node after pump has inflow, but force main after that node and everything after it doesn't have any inflow.</p><p></p><p>Do you know where I am missing something?</p><p></p><p>Thanks!</p><p></p><p></p></div>Usage of control ruleshttps://swmm2000.com/forum/topics/usage-of-control-rules2011-10-10T10:22:59.000Z2011-10-10T10:22:59.000ZUpakahttps://swmm2000.com/members/Upaka<div><p>Hi,</p><p>This is about the control rules.</p><p>I am trying to simulate a network with the help of control rules.</p><p>Total simulation period is 2 hrs and 30 minutes, however, I'm running the simulation part by part. Eg 0 to 15 minutes, 15 to 30 minutes, 30 to 45 minutes and so on.</p><p>I wanted to input the state of the storage tanks, nodes, conduits of the previous simulation to the next simulation. </p><p>As an example, the depth of the tank1 at 15 minutes from 0 to 15 minutes simulation should be input to the 15 to 30 minutes simulation. This is to keep the mass balance.</p><p> </p><p>I think the depths can be input using the following control rule. But, I am not sure. If these are incorrect, please let me know the correct rules too.</p><p> </p><p>IF SIMULATION CLOCKTIME = 00:15:00</p><p>THEN Tank1 DEPTH = 0.4</p><p>AND Tank2 DEPTH = 0.5</p><p>AND Node1 DEPTH = 0.3</p><p>AND Conduit1 DEPTH = 0.15</p><p> </p><p>However, I wanted to input the pollutant concentration levels at these locations.</p><p>There are 5 different pollution constituents and if the above control rules are correct, please reveal me the control rules to feed the pollution concentration levels.</p><p> </p><p>The second question is;</p><p>What will be the maximum number of control rules that I can insert to the simulation. I mean is there a maximum number of control rules that we can use?</p><p> </p><p>Thanks a lot. </p></div>Parallel Pumpshttps://swmm2000.com/forum/topics/parallel-pumps2011-06-10T13:19:32.000Z2011-06-10T13:19:32.000ZPriscilla Screenhttps://swmm2000.com/members/PriscillaScreen<div>Do you know if SWMM5 has a parallel pump tool like the Water does? Do we have to draw in the lag pump or is there a button we can asign it to the lead pump?</div>SWMM Hydraulic modellinghttps://swmm2000.com/forum/topics/swmm-hydraulic-modelling2010-03-23T09:46:50.000Z2010-03-23T09:46:50.000ZUpakahttps://swmm2000.com/members/Upaka<div>Hi,<div>Does anyone have the mathematical explanation for solving St. Venant Equations in SWMM?<div>I was able to find the SWMM Runoff Algorithm but couldn't the Dynamic wave routing.</div><div>Thanks a lot.</div><div>Upaka</div></div></div>SWMM 5 Hydraulic Graphshttps://swmm2000.com/forum/topics/swmm-5-hydraulic-graphs2010-01-23T01:01:17.000Z2010-01-23T01:01:17.000ZRobert Dickinsonhttps://swmm2000.com/members/doonePlace<div><b>Possible Hydraulic Graphical Variables in SWMM 5</b>
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</div>Dynamic Wave A and R calculation slider in SWMM 5.0.013https://swmm2000.com/forum/topics/6651140:DiscussionEntry:86922008-04-20T23:50:20.000Z2008-04-20T23:50:20.000ZHydraulicshttps://swmm2000.com/members/Hydraulics<div><font face="Verdana" size="3"><b>Purpose:</b> The purpose of this note is to explain a significant dynamic wave routing difference between EPA SWMM 5.0.013 and EPA SWMM 5.0.011 and before. A few people have detected a difference. The previous solution(s) would use only the midpoint area (Amid) and hydraulic radius (Rmid) in the dynamic wave solution. The new solution will use a slider or linear combination of the midpoint area (Amid) and hydraulic radius (Rmid) and the upstream cross sectional area (A1) and hydraulic radius (R1). The slider is based on the Froude number in the link. The change involves the A and R link spacing in the two dominant terms of the St. Venant Equation:</font> <br/><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340505?profile=original"/><br/><br/><font face="Verdana" size="3">The new method is a linear combination or slider that weights the value of A and R in the St. Venant Equation based on the value of rho (<img style="WIDTH: 19px; HEIGHT: 17px" height="32" src="http://storage.ning.com/topology/rest/1.0/file/get/3284340634?profile=original" width="83"/></font><font face="Verdana" size="3">), or</font> <br/><br/><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340780?profile=original"/><br/><br/><font face="Verdana" size="3">where, Rho (<img style="WIDTH: 19px; HEIGHT: 17px" height="32" src="http://storage.ning.com/topology/rest/1.0/file/get/3284340634?profile=original" width="83"/></font><font face="Verdana" size="3">) is a function of the Froude number. The effect of this addition is that as the Froude number increases from 0.5 to 1.0 and beyond the area and hydraulic radius used as the pivot point in the St. Venant equation moves from the midpoint of the link to the upstream end of the link. When the Froude number is above 1.0 the St. Venant and Normal Flow equation both use the same cross sectional area and hydraulic radius which makes for a more stable model.</font><br/><br/><font face="Verdana" size="3">Just for reference, the equation for Qnorm or the Manning's Equation flow is</font> <br/><br/><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340937?profile=original"/><br/><br/><font face="Verdana" size="3">The equations for the calculation of Rho (<img style="WIDTH: 19px; HEIGHT: 17px" height="32" src="http://storage.ning.com/topology/rest/1.0/file/get/3284340634?profile=original" width="83"/></font><font face="Verdana" size="3">) as a function of the Froude Number (Fr) are:</font> <br/><br/><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284341079?profile=original"/><br/><br/><font face="Verdana" size="3">If ALL of the follow conditions are true Rho (<img style="WIDTH: 19px; HEIGHT: 17px" height="32" src="http://storage.ning.com/topology/rest/1.0/file/get/3284340634?profile=original" width="83"/></font><font face="Verdana" size="3">) is calculated:</font><br/><ul><li><font face="Verdana" size="3">the pipe is not full,</font></li><li><font face="Verdana" size="3">h1 >= h2, and</font></li><li><font face="Verdana" size="3">qLast > 0.</font></li></ul><p><font face="Verdana" size="3">where,</font><br/><font face="Verdana" size="3">h1 is the head at the upstream end of the link,</font><br/><font face="Verdana" size="3">h2 is the head at the downstream end of the link and</font><br/><font face="Verdana" size="3">qLast is the last flow value in the link. </font><br/><br/><font face="Verdana" size="3">If any of these conditions are true then rho = 1.0 and the value of A and R are the values Amid and Rmid, respectively.<br/>The next graph shows the relationship between Rho and the Froude Number.</font> <br/><br/><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284341829?profile=original"/><br/><br/><font face="Verdana" size="3">The value of Awtd and Rwtd move from the midpoint of the link to the upstream end of the link as the Froude number increases from 0.5 to 1.0.</font> </p><p><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284340780?profile=original"/> <br/><img src="http://storage.ning.com/topology/rest/1.0/file/get/3284342128?profile=original"/><br/> <br/><font face="sans-serif" size="2"> </font><br/><font face="Verdana" size="3"><b>Conclusion:</b> This change should make the solution more stable because there is no longer an oscillation between the St. Venant Equation A and R and the Normal Flow Equation A and R.</font><br/><br/><br/></p></div>