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<?xml-stylesheet type="text/xsl" href="https://communities.bentley.com/cfs-file/__key/system/syndication/rss.xsl" media="screen"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/" xmlns:wfw="http://wellformedweb.org/CommentAPI/"><channel><title>How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/products/hydraulics___hydrology/f/haestad-hydraulics-and-hydrology-forum/228522/how-to-size-a-centrifugal-pump-in-sewercad</link><description>Hi there. 
 I come from the pumping industry in Australia and trialing the use of SewerCAD at the moment, we use steady-state modeling via excel sheets and also some of the other modeling tools available in the market. 
 I have gone through the exercises</description><dc:language>en-US</dc:language><generator>Telligent Community 12</generator><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/707802?ContentTypeID=1</link><pubDate>Thu, 21 Apr 2022 23:38:49 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:442220f0-1160-4b49-bd69-e75e7fe74d9c</guid><dc:creator>Tom Walski</dc:creator><description>&lt;p&gt;Thanks Gary. I agree. WaterCAD (WaterGEMS) . It has more tools than SewerCAD for things like system head curves, combination pump curves and energy costing. You just need to separate out the portion of the system from the wet well to the final discharge point.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/707710?ContentTypeID=1</link><pubDate>Thu, 21 Apr 2022 11:55:23 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:2aa4eb9a-22ce-47ad-b5da-082ac2d04140</guid><dc:creator>Gary Adams</dc:creator><description>&lt;p&gt;For the benefit of other forum viewers, you can use WaterCad to do exactly what you describe above.&lt;/p&gt;
&lt;p&gt;I have used WaterCad to successfully design many sanitary pumping stations.&amp;nbsp; It&amp;#39;s a great tool and easy to use.&amp;nbsp; Once you have a library of pump curves it&amp;#39;s almost a trivial exercise to see which pump works the best for a given configuration.&lt;/p&gt;
&lt;p&gt;WaterCad is also useful for designing and modeling manifolded wastewater pumping stations (which are essentially vastly simplified water distribution systems).&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/707682?ContentTypeID=1</link><pubDate>Thu, 21 Apr 2022 09:36:28 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:12a89149-9533-4c45-8323-d8c495053122</guid><dc:creator>Imran Saheer</dc:creator><description>&lt;p&gt;Thank you Yashodhan for your time and effort to clarify this issue, this is what I like about Bentley, a fantastic team to respond to whenever you needed the most.&amp;nbsp;&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/706957?ContentTypeID=1</link><pubDate>Mon, 18 Apr 2022 06:26:47 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:513cffe2-aa27-42fa-ad5a-fa651730100c</guid><dc:creator>Yashodhan Joshi</dc:creator><description>&lt;p&gt;Hi Imran,&lt;/p&gt;
&lt;p&gt;I checked your model but it doesn&amp;#39;t have any pump curve defined. If your intention was to determine the pump curve see the following steps I followed. I have sent you the modified model via private message.&lt;/p&gt;
&lt;p&gt;1. Using the information from the earlier article you went through (&lt;a href="/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/16879/estimating-a-pump-curve-for-a-model" rel="noopener noreferrer" target="_blank"&gt;Estimating Pump Curve&lt;/a&gt;) I setup the model in such a way that I could estimate the head required. See the scenario &amp;quot;Without Pump&amp;quot; in the shared model. With the difference in HGL at J-1 and J-2 being 13.68 m and flow required as 10 L/s (as per your minimum required) I could setup Test Pump Curve-1.&lt;/p&gt;
&lt;p&gt;2. I ran this model with pump in scenario &amp;quot;With Pump @13.68 m head / 10 L/s&amp;quot;. In this scenario I checked the System Head Curve as per the article shared by Tom. The system head curve gave me value of head as approximately 18.75 m and flow of 5.2 L/s (which is what is actually calculated).&lt;/p&gt;
&lt;p&gt;3. With these values I setup Test Pump Curve-2 and ran the scenario &amp;quot;With Pump@ 16.75 m head / 5.2 L/s&amp;quot;.&lt;/p&gt;
&lt;p&gt;You can refine the pump curve like this iteratively. What the system head curve shows are the required values. In your case, you require 10 L/s as flow due to scouring requirement, so you can change the pump curves accordingly.&lt;/p&gt;
&lt;p&gt;I have leveraged the &lt;a href="/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/4508/scenario-and-alternative-management" rel="noopener noreferrer" target="_blank"&gt;Scenarios and Alternatives&lt;/a&gt; functionality in our products here.&lt;/p&gt;
&lt;p&gt;Also, since you are new to SewerCAD, I would also recommend you go through the below article which points to various learning resources;&lt;/p&gt;
&lt;p&gt;&lt;a href="/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/10563/learning-resource-guide-for-new-users-of-sewercad" rel="noopener noreferrer" target="_blank"&gt;Learning Resource Guide for New Users of SewerCAD&lt;/a&gt;&lt;/p&gt;
&lt;p&gt;Let me know if this helps.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/706940?ContentTypeID=1</link><pubDate>Mon, 18 Apr 2022 04:53:08 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:38a589c1-2fa5-470a-9157-14c4cf58fad3</guid><dc:creator>Imran Saheer</dc:creator><description>&lt;p&gt;Hi Yashodhan,&lt;/p&gt;
&lt;p&gt;thanks for your response, please see below.&amp;nbsp;&lt;/p&gt;
&lt;p&gt;Hope I have packaged it correctly.&amp;nbsp;&lt;/p&gt;
&lt;p&gt;Cheers.&lt;/p&gt;
&lt;p&gt;Imran&lt;/p&gt;
&lt;p&gt;&lt;a href="https://communities.bentley.com/cfs-file/__key/communityserver-discussions-components-files/5925/TestPSsystemhead.stswpkg.zip"&gt;communities.bentley.com/.../TestPSsystemhead.stswpkg.zip&lt;/a&gt;&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/706938?ContentTypeID=1</link><pubDate>Mon, 18 Apr 2022 04:26:07 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:4aee6534-af4a-4499-a7c5-d0bbdd5b9b80</guid><dc:creator>Yashodhan Joshi</dc:creator><description>&lt;p&gt;Hello Imran,&lt;/p&gt;
&lt;p&gt;I can see that you have only shared the &amp;quot;TestPSystemhead.stsw&amp;quot; file. We would also need the &amp;quot;&lt;span&gt;TestPSystemhead.stsw.sqlite&amp;#39; file to open the model. The best option is to go to File &amp;gt; Save as Package and &lt;a href="/help/w/be_communities_help/32255/sharing-hydraulic-model-files-on-the-openflows-hydraulics-hydrology-forum" rel="noopener noreferrer" target="_blank"&gt;share&lt;/a&gt; it with us.&lt;/span&gt;&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/706924?ContentTypeID=1</link><pubDate>Mon, 18 Apr 2022 02:21:57 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:0a54ef1c-8362-4cef-9f71-90852e7c3b2a</guid><dc:creator>Imran Saheer</dc:creator><description>&lt;p&gt;Hi Tom, thanks for your help so far, and I have gone through the wiki you have provided, and&amp;nbsp;understanding it relating to SewerCAD seems to be a bit hard for me especially as I have recently started with SewerCAD,&lt;/p&gt;
&lt;p&gt;I have quickly mocked up a model and have attached it here (this is not relevant to my initial info provided earlier), can you please have a look and let me know how would you find out the head needs to be if the required flow is to be around 10L/s?&amp;nbsp;&lt;/p&gt;
&lt;p&gt;&lt;em&gt;the catchment has a 500 population with 180L/d as the average per capita and I have used 5 as the factor for peak wet flows. That comes closer to 5.2L/s flow into the pumping station, but due to the scouring requirement on the forcemain the pumped flow rate has to be a min of 10L/s,&lt;/em&gt;&lt;/p&gt;
&lt;p&gt;How would you change the model to get the required head without including a pump curve?&lt;/p&gt;
&lt;p&gt;Sorry about my queries as I am trying to get to the bottom of it with your help,&lt;/p&gt;
&lt;p&gt;appreciate your help.&amp;nbsp;&lt;/p&gt;
&lt;p&gt;Cheers.&lt;/p&gt;
&lt;p&gt;&amp;nbsp;&lt;a href="https://communities.bentley.com/cfs-file/__key/communityserver-discussions-components-files/5925/TestPSsystemhead.stsw"&gt;communities.bentley.com/.../TestPSsystemhead.stsw&lt;/a&gt;&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/706913?ContentTypeID=1</link><pubDate>Mon, 18 Apr 2022 01:16:42 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:a8c0999e-c77d-4991-8f28-67b309dd0df9</guid><dc:creator>Tom Walski</dc:creator><description>&lt;p&gt;The wiki below should answer your questions.&lt;/p&gt;
&lt;p&gt;&lt;a href="/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/24627/understanding-system-head-curves-in-watergems-watercad-and-sewercad"&gt;https://communities.bentley.com/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/24627/understanding-system-head-curves-in-watergems-watercad-and-sewercad&lt;/a&gt;&lt;/p&gt;
&lt;p&gt;If you want to find the head manually, you can remove the pump from the model and put an inflow at the pump discharge point equal to the design flow. The model will tell you the head needed. Subtract the head inside the wet well and that remaining head is the head the pump needs to add.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/706910?ContentTypeID=1</link><pubDate>Mon, 18 Apr 2022 00:32:45 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:df943056-052a-4791-9422-cd4d159c5ef5</guid><dc:creator>Imran Saheer</dc:creator><description>&lt;p&gt;Hi Tom,&amp;nbsp;&lt;/p&gt;
&lt;p&gt;if I have candidate pumps available I know how to create a system head curve, my question is regarding the first step, how do we know the required system head if the flow is known (I can do this in various other ways but I would like to know how this is modeled in SewerCAD).&lt;/p&gt;
&lt;p&gt;So once the required duty point is known we can obtain the most suitable pump in the market / based on client specifications. I have been trying to work out how to model a system when you don&amp;#39;t have a pump selection and find that duty point if flow is known (as I have explained in my initial post).&lt;/p&gt;
&lt;p&gt;Cheers.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/706898?ContentTypeID=1</link><pubDate>Sun, 17 Apr 2022 15:39:07 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:82a101e7-1157-4620-9a83-0a6dcc68dca6</guid><dc:creator>Tom Walski</dc:creator><description>&lt;p&gt;For step 3, make sure the calc option is set to GVF-Convex.&amp;nbsp;Create a pump definition (Components) for&amp;nbsp;one of your candidate pumps into the pump definition for this model scenario. Run the model to make sure the results are reasonable. Right click on the pump and pick System Head Curve. Pick the compute button in the system head curve dialog.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/706897?ContentTypeID=1</link><pubDate>Sun, 17 Apr 2022 14:12:26 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:698eb371-1197-4ea3-a272-9ef7f06680ad</guid><dc:creator>Imran Saheer</dc:creator><description>&lt;p&gt;Correct, we normally go with Flygt N type impellers, and we ensure the riser and rising main all sized to max particle size comes through the impellers. To our specs, the riser has to be min 80mm in dia. and the rising main (force main) to be of min 100mm in ID.&amp;nbsp;&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/706896?ContentTypeID=1</link><pubDate>Sun, 17 Apr 2022 14:09:00 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:c45cb215-e7b8-4890-b209-3a4de5bc8782</guid><dc:creator>Imran Saheer</dc:creator><description>&lt;p&gt;Hi Tom,&amp;nbsp;&lt;/p&gt;
&lt;p&gt;appreciate your response to this,&amp;nbsp;&lt;/p&gt;
&lt;p&gt;I am quite familiar with everything except item #3, I am not sure how to model this in SewerCAD without giving the pump curve, if you or someone could explain this that would be beneficial.&amp;nbsp;&lt;br /&gt;Thanks in advance&amp;nbsp;&lt;/p&gt;
&lt;p&gt;Imran&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/706895?ContentTypeID=1</link><pubDate>Sun, 17 Apr 2022 12:36:16 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:93931f03-1105-4ac1-b74a-1a197a0444d2</guid><dc:creator>Tom Walski</dc:creator><description>&lt;p&gt;There are other considerations of course such as whether to use a submersible or dry pit. For a small station like this, a submersible is typical.&lt;/p&gt;
&lt;p&gt;Then there is type of impeller. A closed, multi-vane impeller is usually the most efficient. However, it is the most likely to clog with solids and rags. Depending on the type of solids you expect, you may want to favor an open impeller with fewer vanes for wastewater.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: How to size a centrifugal pump in SewerCAD?</title><link>https://communities.bentley.com/thread/706894?ContentTypeID=1</link><pubDate>Sun, 17 Apr 2022 12:27:56 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:85deea4e-4d52-46e1-abc9-3287be73cf70</guid><dc:creator>Tom Walski</dc:creator><description>&lt;p&gt;The overall steps work like this.&lt;/p&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;ol&gt;
&lt;li&gt;Pick a design flow for the pump. The value should be a little higher than the peak inflow. The inflow will vary over time and will rarely high the peak.&lt;/li&gt;
&lt;/ol&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;ol start="2"&gt;
&lt;li&gt;Size the force main such that the velocity is greater than 2 ft/s and less than 8 ft/s when the pump is on.&lt;/li&gt;
&lt;/ol&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;ol start="3"&gt;
&lt;li&gt;Generate the system head curve for the pump. Generate the system head curve. You need to use the GVF-Convex solver for this. This calculation will show you the head you need to provide at you design flow rate.&lt;/li&gt;
&lt;/ol&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;ol start="4"&gt;
&lt;li&gt;Now pick several alternative pumps which produce that flow at that head. Run each through the model (use scenario manager). Determine the operating point of reach pump and see what the pump efficiency is at that operating point.&lt;/li&gt;
&lt;/ol&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;ol start="5"&gt;
&lt;li&gt;Check the operation by running an extended period simulation to see how the pump will cycle, not just at peak time but on normal days. If it is cycling too frequently, you may need to upsize the wet well or downsize if the cycle is too slow.&lt;/li&gt;
&lt;/ol&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;ol start="6"&gt;
&lt;li&gt;Those steps should get you a reasonable pump. However, to do a really want to pick the best pump use WaterGEMS&amp;rsquo; scenario energy costing tool to determine the present worth of energy cost. The biggest component of life cycle cost is usually energy and sometimes the least expensive pump is the most costly to run.&lt;/li&gt;
&lt;/ol&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>