This class begins with the basics of hydraulics theory as it applies to water distribution modeling, then takes students through more advanced topics such as: working with multiple scenarios and alternatives; model calibration; pump selection; energy and cost studies; extended-period simulation; fire flow analysis; identifying critical links or shortfalls within a water system; and finally pipe renewal planning. Students will become familiar with WaterCAD and use the software to reinforce concepts with case studies. As WaterCAD and WaterGEMS capabilities are the same throughout this course, users will gain an understanding of both software applications. Live training courses are very interactive. Students will continually engage with the instructor to ensure a successful learning outcome that includes a course assessment. Instructor: Martin Pflanz
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Water Distribution Design and Modeling Fundamentals
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SIG Workshop: Bentley Hydraulics & Hydrology
Join technology expert Martin Pflanz for this complimentary, one-hour Bentley Hydraulics & Hydrology Special Interest Group (SIG) virtual workshop. You can expect a full agenda of discussion and demonstration designed to keep you informed and working optimally: Hear the latest in hydraulic and hydrology technology and software functionality Learn how to best apply capabilities to your projects and workflows Network with industry colleagues and connect with Bentley experts This SIG session is live, interactive, and addresses topics important to your success. Learn, engage, and connect! Registration link for Session #1 (9 AM US Eastern time)
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SIG Workshop: Bentley Hydraulics & Hydrology
Join technology expert Martin Pflanz for this complimentary, one-hour Bentley Hydraulics & Hydrology Special Interest Group (SIG) virtual workshop. You can expect a full agenda of discussion and demonstration designed to keep you informed and working optimally: Hear the latest in hydraulic and hydrology technology and software functionality Learn how to best apply capabilities to your projects and workflows Network with industry colleagues and connect with Bentley experts This SIG session is live, interactive, and addresses topics important to your success. Learn, engage, and connect! Registration link for Session #2 (7 PM US Eastern time)
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Sewer System Design and Modeling Fundamentals
This training class includes discussions and hands-on workshops on collection system hydraulics, new system design, master planning, capacity analysis, and rehabilitation, for wastewater collection systems. In addition to instruction on how the models work, students complete hands-on exercises using SewerGEMS or SewerCAD software. Both steady-state and extended-period simulations (through time) are presented in this course, as well as gravity and pressure system components. Attendees learn to customize plan and profile sheets and tabular reports. Exercises apply SewerGEMS and SewerCAD tools to leverage existing GIS and database information to build models and populate loadings. Instructor: Kristen Dietrich
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Training: Transient Analysis and Design
This transient analysis training teaches the student how to understand the causes of hydraulic transients and water hammer, and learn how to protect systems against them. Through this course, you will gain the knowledge necessary to recognize the types of systems prone to transients and to proactively manage the associated risks. Hands-on exercises and real-world examples will enrich your learning experience with a convenient balance of strong transient flow theory and the application of a robust software tool. Live training courses are very interactive. Students will continually engage with the instructor to ensure a successful learning outcome that includes a course assessment. Instructor: Jesse Dringoli
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Training: Water Distribution Design and Modeling Fundamentals
This class begins with the basics of hydraulics theory as it applies to water distribution modeling, then takes students through more advanced topics such as: working with multiple scenarios and alternatives; model calibration; pump selection; energy and cost studies; extended-period simulation; fire flow analysis; identifying critical links or shortfalls within a water system; and finally pipe renewal planning. Students will become familiar with WaterCAD and use the software to reinforce concepts with case studies. As WaterCAD and WaterGEMS capabilities are the same throughout this course, users will gain an understanding of both software applications. Live training courses are very interactive. Students will continually engage with the instructor to ensure a successful learning outcome that includes a course assessment. Instructor: Bahtigul Varol
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Forum Post: RE: initial pressure less than vapor pressure - previously proposed resolutions unsuccessful
Hello Vanessa, It sounds like you are having trouble with the Initial Conditions in HAMMER. This could be due to a number of different problems. It could be something simple or something complex, but it is difficult to tell without seeing the model. To help you with this, it would be best to take a look at a copy of your model. Please see below for how to send it: communities.bentley.com/.../32255.sharing-hydraulic-model-files-on-the-haestad-forum
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Wiki Page: Cumulative patch sets for Hydraulics and Hydrology products
Applies To Product(s): WaterCAD, WaterGEMS, HAMMER, SewerCAD, SewerGEMS, StormCAD, CivilStorm, PondPack Version(s): 08.11.XX.XX Area: Installation Original Author: Mark Pachlhofer, Bentley Technical Support Group Background Cumulative patch sets for Haestad | Hydraulics and Hydrology products provide fixes to previously reported software problems. See above for a list of applicable Haestad products. As the name implies, these patches are cumulative, including all available fixes for the respective version (see further below for how to find the list.) Patches contain mostly .DLL files which automatically replace other .DLL files in the installation folder for a particular Haestad product that contained the reported issue. Where can I download cumulative patch sets? Currently, cumulative patch sets can be requested by contacting Bentley Technical Support, if the latest patch is not in the Fulfillment Center (more on downloading here ). Why doesn't the version number change after installing a patch? Currently, the cumulative patch sets replace individual patched files (mostly .DLL files) in the product’s installation folder for issues reported by users for that particular version of the product. This is different from Bentley products that use “priority builds” - a full installation file that includes the patched issue, with a new build number. There is value in uniquely identifying patched versions (especially when managing large deployments, where it is important for all users to be on the same "update") but there is also value in the ease-of use for patch sets (quicker installation, no compatibility concerns). As a compromise, current patch sets will update the date seen in the product’s “About ” window to show the date of the patch that was created. This way, a user can check if they have a patch (and if other colleagues in their company have are on the same patch) by looking at this date. Where can I find a list of fixes included in a cumulative patch set? A list of the fixes included with the patch set is currently deployed to the product’s installation folder, "C:\Program Files (x86)\Bentley\ " on a 64-bit computer and "C:\Program Files\Bentley\ " on a 32-bit computer. The file is a text file named similar with this convention: " _PathLog.txt" (e.g. WaterGEMS_PatchLog.txt). See Also Downloading Haestad / Hydraulics and Hydrology Software What is the installation order for the product files that I have downloaded? How can I find out when a new version or patch is released for a Hydraulics and Hydrology product?
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Forum Post: RE: Comparison hydrographs- Civil Storm and another two models (using SCS method)
Hi Jesse, Thank you very much for the reply. Yes, once I deleted IA value, hydrographs are matching.
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Wiki Page: Why Pressure(calculated residual) field is N/A?
Product(s): Bentley WaterGEMS, WaterCAD Version(s): 08.11.XX.XX Area: Output and Reporting Problem Why Pressure (calculated residual) field is N/A? Background Residual pressure field is available for fire flow analysis, but that is shown as N/A for the hydraulic analysis, flushing, water quality analysis etc. Solution Residual pressure is nothing but the calculated pressure at any node. Pressure (calculated residual) field is basically used for fire flow analysis only to understand how much residual pressure is there at that junction or hydrant. Apart from fire flow analysis Pressure (calculated residual) field is calculated as N/A for all other types of calculations. See Also
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Wiki Page: [Deleted] When trying to open a new or existing project I get this error: System.NullReferenceException: Object reference not set to an instance (Solution 500000068126)
Applies To Product(s): Bentley WaterCAD Version(s): N\A Environment: N\A Area: Output and Reporting Subarea: N\A Original Author: Bentley Technical Support Group Problem Cannot open new project or existing project without getting an internal error below. System.NullReferenceException: Object reference not set to an instance of an object. at _com_ptr_t _com_IIID ADODB::Connection15 , & _GUID_00000515_0000_0010_8000_00aa006d2ea4> >._QueryInterface struct IUnknown *>(_com_ptr_t _com_IIID ADODB::Connection15\,\ & _GUID_00000515_0000_0010_8000_00aa006d2ea4> >* , IUnknown* p) at _com_ptr_t _com_IIID ADODB::Connection15 , & _GUID_00000515_0000_0010_8000_00aa006d2ea4> >.{ctor} struct IUnknown>(_com_ptr_t _com_IIID ADODB::Connection15\,\ & _GUID_00000515_0000_0010_8000_00aa006d2ea4> >* , IUnknown* p) at Haestad.Domain.DaoInterop.AdoXLibrary.CloseAdoConnection(IntPtr connection) at Haestad.Domain.DataObjects.Dao.DaoDataConnectionBase.VerifyAutoNum berColumns() at Haestad.Domain.DataObjects.Dao.DaoDataConnectionBase.UpdateCaches( CompactOperationContext context) at Haestad.Domain.DataObjects.Dao.DaoDataConnectionBase.Compact(Compa ctOperationContext context) at Haestad.Domain.DataObjects.Dao.DaoDataConnectionBase.OpenImpl(Boolean checkSchemaVersion, Boolean initializeActiveDomainDataSetTypeId) at Haestad.Domain.DataObjects.Dao.DaoDataConnectionBase.Open() at Haestad.Domain.ModelingObjects.DataSourceBase.Open() at Haestad.Framework.Application.DomainDatabaseFile.OpenDataSource(IM essageQuestionHandler aimsgHandler, IProgressIndicator aiprogressIndicator) at Haestad.Framework.Application.DomainDatabaseFile.OpenDataSource(String astringPathTransaction, IMessageQuestionHandler aimsgHandler, IProgressIndicator aiprogressIndicator) at Haestad.Framework.Application.DomainDatabaseFileWithResults.Create AndOpenDataSource(String astringPathNominal, String astringPathTransaction, IMessageQuestionHandler aimsgHandler, IProgressIndicator aiprogressIndicator) at Haestad.Framework.Application.DomainDatabaseFile.CreateAndOpenProj ectStore(String astringPathNominal, IMessageQuestionHandler aimsgHandler, IProgressIndicator aiprogressIndicator) at Haestad.Framework.Application.ProjectFileBase.Create(ProjectProperties app) at Haestad.Framework.Application.DomainDatabaseFile.Create(ProjectPro perties app) at Haestad.Framework.Application.ProjectBase.Create(ProjectProperties app) at Haestad.Framework.Application.DomainProjectBase.Create(ProjectProperties app) at Haestad.Drawing.Domain.GraphicalDomainProjectBase.Create(ProjectPr operties app) at Haestad.Framework.Application.ProjectManagerBase.CreateUntitledPro ject(ProjectProperties app) at Haestad.Framework.Application.HaestadParentFormModel.NewUntitledPr oject(ProjectProperties app) at Haestad.Framework.Windows.Forms.Forms.HaestadParentForm.NewUntitle dFile(ProjectProperties app) at Haestad.Framework.Windows.Forms.Application.HaestadParentFormUIMod elBase.NewUntitledProject(ProjectProperties app) at Haestad.Drawing.Control.Forms.GraphicalDrawingParentForm.FileNew() at Haestad.Framework.Windows.Forms.Forms.WelcomeForm.buttonCreateNewP roject_Click(Object sender, EventArgs e) at System.Windows.Forms.Control.OnClick(EventArgs e) at System.Windows.Forms.Button.OnClick(EventArgs e) at System.Windows.Forms.Button.WndProc(Message & m) at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message & m) at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message & m) at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) Solution Please try re-registering msado15.dll and msadox.dll (under c:\program files\common files\system\ado). To register the program, go to start menu > run command line and type in CMD. This should bring up the DOS commad line. Then type in cd.. and repeat it until you see just the C:\ command prompt. Then type in the following command. C:\Program Files\Common Files\System\ado>regsvr32 msado15.dll C:\Program Files\Common Files\System\ado>regsvr32 msadox.dll
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Wiki Page: Using The Network Navigator
Applies To Product(s): WaterCAD, WaterGEMS, HAMMER Version(s): 10.00.xx.xx, 08.xx.xx.xx Area: Modeling Original Author: Shahzab Bukhari, Bentley Technical Support Group Overview The Network Navigator consists of a toolbar and a table that lists the Label and ID of each of the elements contained within the current selection. Predefined queries can help you select certain queries with an ease without spending too much time. To open the Network Navigator in CONNECT Edition, go to the Analysis tab and choose Navigator. In the V8i releases, click the View menu and select Network Navigator, or click the Network Navigator button on the View toolbar. Physical Overview of Network Navigator Predefined Queries The Network Navigator provides access to a number of predefined queries grouped categorically, accessed by clicking the [>] button. Categories and the queries contained therein include Network Network queries include "All Elements" queries for each element type, allowing you to display all elements of any type in the Network Navigator. Network Review Network Review Queries include the following: Nodes In Close Proximity - Identifies nodes within a specific tolerance. Crossing Pipes - Identifies pipes that intersect one another with no junction at the intersection. Orphaned Nodes - Identifies nodes that are not connected to a pipe in the model. Orphaned Isolation Valves - Identifies isolation valves that are not connected to a pipe in the model. Dead End Nodes - Identifies nodes that are only connected to one pipe. Dead End Junctions - Identifies junctions that are only connected to one pipe. Pipe Split Candidates - Identifies nodes near a pipe that may be intended to be nodes along the pipe. The tolerance value can be set for the maximum distance from the pipe where the node should be considered as a pipe split candidate. Pipes Missing Nodes - Identifies which pipes are missing either one or both end nodes. Duplicate Pipes - Identifies instances in the model where a pipe shares both end nodes with another pipe. Network Trace Network Trace Queries include the following: Find Connected - Locates all the connected elements to the selected element in the network. Find Adjacent Nodes - Locates all node elements connected upstream or downstream of the selected element or elements. Find Adjacent Links - Locates all link elements connected upstream or downstream of the selected element or elements. Find Disconnected - Locates all the disconnected elements in the network by reporting all the elements not connected to the selected element. Find Shortest Path - Select a Start Node and a Stop Node. The query reports the shortest path between the two nodes based upon the shortest number of edges. Trace Upstream - Locates all the elements connected upstream of the selected downstream element. Trace Downstream - Locates all the elements connected downstream of the selected upstream element. Isolate - Select an element that needs to be serviced. Run the query to locate the nearest isolation valves. In order to service the element, this will identify where shut off points and isolation valves are located. Find Initially Isolated Elements - Locates elements that are not connected or cannot be reached from any boundary condition. Input Input Queries include a number of queries that allow you to find elements that satisfy various conditions based on input data specified for them. Input queries include : Duplicate Labels - Locates duplicate labels according to parameters set by the user. See Using the Duplicate Labels Query for more information. Elements With SCADA Data - Locates elements that are have SCADA data associated with them. Inactive Elements - Locates elements that have been set to Inactive. Pipes with Check Valves - Locates pipes that have the Has Check Valve? input attribute set to True. Controlled Elements - Locates all elements that are referenced in a control Action. Controlled Pumps - Locates all pumps that are referenced in a control Action. Controlled Valves - Locates all valves that are referenced in a control Action. Controlled Pipes - Locates all pipes that are referenced in a control Action. Controlling Elements - Locates all elements that are referenced in a control Condition. Initially Off Pumps - Locates all pumps whose Status (Initial) input attribute is set to Off. Initially Closed Control Valves - Locates all control valves whose Status (Initial) input attribute is set to Closed. Initially Inactive Control Valves - Locates all control valves whose Status (Initial) input attribute is set to Inactive. Initially Closed Pipes - Locates all pipes whose Status (Initial) input attribute is set to Closed. Fire Flow Nodes - Locates nodes included in the group of elements specified in the Fire Flow Alternative's Fire Flow Nodes field. Constituent Source Nodes - Locates all nodes whose Is Constituent Source? input attribute is set to True. Nodes with Non-Zero Initial Constituent Concentration - Locates all nodes whose Concentration (Initial) input attribute value is something other than zero. Tanks with Local Bulk Reaction Rate Coefficient - Locates all tanks whose Specify Local Bulk Rate? input attribute is set to True. Pipes with Local Reaction Rate Coefficients - Locates all pipes whose Specify Local Bulk Reaction Rate? input attribute is set to True. Pipes with Hyperlinks - Locates all pipes that have one or more associated hyperlinks. Nodes with Hyperlinks - Locates all nodes that have one or more associated hyperlinks. Results Results Queries include a number of queries that allow you to find elements that satisfy various conditions based on output results calculated for them. Results queries include: Negative Pressures - Locates all nodes that have negative calculated pressure results. Pumps Operating Out of Range - Locates all pumps whose Pump Exceeds Operating Range? result attribute displays True. Pumps Cannot Deliver Flow or Head - Locates all pumps whose Cannot Deliver Flow or Head? result attribute displays True. Valves Cannot Deliver Flow or Head - Locates all valves whose Cannot Deliver Flow or Head? result attribute displays True. Empty Tanks - Locates all tanks whose Status (Calculated) result attribute displays Empty. Full Tanks - Locates all tanks whose Status (Calculated) result attribute displays Full. Off Pumps - Locates all pumps whose Status (Calculated) result attribute displays Off. Closed Control Valves - Locates all control valves whose Status (Calculated) result attribute displays Closed. Inactive Control Valves - Locates all control valves whose Status (Calculated) result attribute displays Inactive. Closed Pipes - Locates all pipes whose Status (Calculated) result attribute displays Closed. Failed Fire Flow Constraints - Locates all elements whose Satisfies Fire Flow Constraints? result attribute displays False. See Also Product TechNotes and FAQs Haestad Methods Product Tech Notes And FAQs [[General WaterGEMS V8 FAQ|General WaterGEMS V8 FAQ]] Hydraulics and Hydrology Forum External Links Bentley SELECTservices Bentley LEARN Server
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Wiki Page: Surge mitigation for systems with intermediate high points experiencing negative pressure
Applies To Product(s): HAMMER Version(s): 08.11.XX.XX, 10.00.XX.XX Area: Modeling Original Author: Jesse Dringoli, Bentley Technical Support Group Problem Description When computing a transient simulation with an emergency pump shutdown, no matter what surge protection I try to put in place, it does not seem to help with negative pressures. Reason Take a close look at the profile of your system. If you're pumping over a hill and the boundary conditions on either end of the system are lower, than it may not be possible to maintain a positive pressure, so long as the pump(s) remain off. Basically when the pump turns off and the HGL drops, even if you had multiple tanks along the pipeline, they may help protect the system at first, but will eventually drain out and cause the HGL to drop to low levels. This can cause vapor pocket formation. When vapor pockets collapse, they can cause severe pressure spikes (or "upsurges"). If you only have air valves as protection, it's important to note that they can only limit the pressure from dropping below zero in the immediate vicinity of the air valve. Pressure can still become subatmospheric some distance to either side of the air valve. There are a number of factors that come into play, including the physical topology and angle of the surge wave as it approaches the air valve location. In some cases, other protective measures may be necessary, such as a tank or pump flywheel (increased inertia). Another factor to consider is what happens when air is released back out of the air valves. If a controlled air release does not occur (such as with a triple acting air valve or smaller outflow orifice diameter with a double acting air valve) then the adjacent water columns can rejoin too quickly, causing a severe upsurge, which can reflect and combine with other waves, causing severe a downsurge. The best way to visualize and understand if this is happening is to animate a profile path of the area in question. In your transient solver Calculation Options, make sure you have selected "True" for "Generate Animation data", then open the Profile of "Hydraulic Grade and Air/Vapor Volume" for a profile covering the area of interest. Click the play button at the top or move the time bar to animate the transient simulation and get a better understanding of exactly what's happening. You may notice an air or vapor pocket forming (top graph) and later collapsing with subsequent severe surges forming, reflecting and interacting with each other. You may need to consider how long the pumps will be off and size the surge protection device(s) based on that. You can use the "variable speed" transient pump type to simulate the pump turning off and then back on, or consider two runs (one for shutdown and the other for start up). For example, if the pump is shut down for 10 minutes the surge protection device would need to mitigate the transient wave for at least that long. In the case of a surge tank (hydropneumatic tank) the tank will need to be sized appropriately for the water to supply the demands and dampen the transient wave for at least the minimum time the pump is off. There may be concerns with how fast any trapped air is released upon startup.
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Wiki Page: What are the limitations of importing/exporting EPANET files?
Applies To Product(s): WaterCAD, WaterGEMS Version(s): 10.00.xx.xx, 08.11.xx.xx Area: Layout and Data Input Original Author: Terry Foster, Bentley Technical Support Group When we do an import/export with EPANET files the only data that will be retained or unaltered is the data that is supported in both EPANET INP format and WaterGEMS or WaterCAD. Items in WaterGEMS and WaterCAD that are not supported in EPANET: VSPs VSPBs Fire Flow Flushing Pressure Dependent Demands Variable reporting time steps Demand/Roughness Adjustments Continuous patterns Elements like Hydropneumatic tanks, air valves, etc. Top-filling options for a tank All HAMMER properties User data Energy costs All presentation settings Isolating valves/criticality All ModelBuilder, LoadBuilder, Darwin, TRex and Skelebrator settings Spot-elevations Isolation Valves Pump curves (EPANET exporter generates a CURVE. However such curves are always imported back - during round-trips - as multi-point pump definition. So if the original pump-definition was a 1-point or 3-point curve the round-trip may not come back to the exact original pump definition type.) Unit Demands Selection Sets Queries Graphs Data from extensions (Calibrator/Designer/Capital-cost) Customer meters Tap/Laterals One other thing that happens when importing EPANET files is that two extra pipes are added for every directed node. They are labeled as something similar to "was added during EPANET import". So when the WaterGEMS or WaterCAD model thus created is exported back to EPANET those extra pipes are removed and the original directed node is rebuilt without the extra pipes. Pumps and Valves Pumps and valves are seen as link elements in EPANET, whereas WaterCAD and WaterGEMS see them as nodes. Therefore on export to EPANET, a new link element must be created to use as the pump/valve. To do that, two overlapping junctions are created to connect to it. The link in EPANET will have the same name as the pump/valve did in WaterCAD or WaterGEMS. In EPANET, an icon will display for the pump and valve, but when trying to double-click on it, the junction could be selected by mistake. For Example, take a look the following valve in WaterGEMS/WaterCAD: Here's what it looks like after exporting to and opening in EPANET: When hovering the mouse over, it may look as if it's a junction: However if you click and drag, you'll see its actually two junctions overlapping (at the original location of the valve in WaterGEMS/WaterCAD) with the PRV link element between them: See Also Should the EPANET solver and the WaterGEMS solver give the same results for a model? What are the difference between WaterGEMS/CAD and EPANET?
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Wiki Page: Troubleshooting Network Unbalanced or Cannot solve network hydraulic equations
Applies To Product(s): Bentley WaterGEMS, Bentley WaterCAD Version(s): 10.00.xx.xx, 08.11.xx.xx Area: Modeling Original Author: Scott Kampa, Bentley Technical Support Group Error or Warning Message How can a user fix the WaterGEMS or WaterCAD error message "Network Unbalanced" or "Cannot solve network hydraulic equations". A "Reverse flow detected" may be encountered as well. Explanation The "Network Unbalanced" and "Cannot solve network hydraulic equations" user notification means that the program could not converge on a balanced solution within the maximum number of trials. The difference between these is that the "Network unbalanced" message can occur for individual time steps, while the "Cannot solve network hydraulic equations" does not specify a time step where the issue occurs. Between calculation iterations, the program checks the relative change in flow, which has a default value of 0.001. If the relative flow change is below the "Accuracy" value designated in the calculation options, the time step is balanced or is said to have converged. If the relative flow change is greater than the Accuracy value, the program will try another iteration. If the program reaches the maximum number of trials without finding a solution, the "Network Unbalanced" user notification is generated. How to Avoid The first thing to do is to check to make sure your entire network is connected properly. Perform a validation (Analysis > Validate) on the model to see if there is information on possible issues in the model. If there are messages that are related to specific elements, double-click on it or right-click and choose "Zoom To", which will select the element in the drawing pane. Check the properties and setup of the element to see if there are issues related to data entry or orientation. If the element is a node, you can click and drag the element to make sure it is connected to all the pipes it is supposed to be connected to. Nodes that are not connected to pipes can occur if you used ModelBuilder to create the model. If your junctions are not connected properly you can use the Batch Pipe Split tool , which will allow you to connect the junctions to the pipes they are supposed to be connected to by splitting them. The Network Navigator tool can help you locate topological issues. (check the "See also" for two links on this) If there are not validation issues, make sure the setup of elements are accurate. Pay close attention to logical controls, valve settings, and valve status, empty or full tanks, and near zero flows as these are common causes of the issue. If you have a check valve on the pipe directly downstream of a pump, consider removing the check valve. In WaterGEMS and WaterCAD, a pump will not allow reverse flow. A check valve on the downstream pipe is redundant and can sometimes impact the model calculations. If you have a significant portion of your model with zero flow (such as the case when modeling "static" conditions), the numerical solver will have a hard time converging on a balanced solution. The reason is because the relative flow change between trials will typically be large in this case, since the numbers that it is dealing with are very close to zero. Check the link in the "See Also" section below for more on this. If you have multiple fixed or variable speed pumps (VSP) discharging into the same pressure zone, this can also cause numerical instability. If the real system includes some manual operation of the pumps in this case, consider matching that in the model by using time based controls or a pattern (is variable speed pump = true, type = pattern). If you have GPV's check the "Flow Demanded" from the calculation summary (Analysis > Calculation Summary) at the time step of the red user notification. If the flow going to that GPV is not enough to provide the flow demanded examine the GPV headloss curve to make sure the maximum value of the curve is large enough to cover that flow. For example, if the flow demanded is 850 gpm check the largest value on the curve is at least 851 gpm. Confirm that tanks have the proper elevation data, including any top-fill tanks that may be in the model. If the model setup is accurate, you can find additional steps to help with this issue below. Intra-Trial Status Messages For EPS simulations you might find more clues to solving your problem by either: 1. (if you have V8i SELECTseries 5 or greater) - Click the time step in question in the Calculation Summary, then click the Intra-Trial details tab. This identifies elements that are changing status between trials 2. (if you have V8i SELECTseries 4 or earlier) - Open the .RPC file. This file contains a log of the trials that the program runs through when it is trying to converge on a solution. In order to open this file browse to the folder where your model is saved; that is where the .RPC file will be. You can open this file in a text editor, such as Notepad. Look down the trial list until you start to see the trials where there are elements that are constantly changing status (for valves a status change may be going from "active" to "closed" or vice versa and for pumps it could be going from "On" to "Off") over consecutive trials. The elements that have a constantly toggling status could be a clue to where your problem lies. If this happens often for certain elements then your model may be to tightly constrained or controlled and you should attempt to simplify the model where possible. If you are seeing many valves oscillating status in a particularly challenging timestep, this is an indication that their configuration should be checked, to ensure that they are correct and not accidentally "fighting against each other" due to the assumed settings. You might be able to adjust the configuration of those valves (in some cases with a conservative assumption) to make the model more simple and stable. In other words, try to address the root of the problem instead of tweaking the options to get it to work. This should be better in the long run if you can identify (with help from the intra-trial status messages) some changes that stabilize the model. For example this article talks about challenges like this that can occur with PRVs in parallel. Of course in some cases you may need to adjust the calculation options, in which case it does make sense to be extra cautious. Calculation Options Several advanced calculation options are available to help with convergence in challenging situations where the model data input and topology has been checked. First, you can try increasing the number of trials. To do this, go to Analysis > Calculation Options. Under the "Steady State/EPS Solver" section, double-click on the active calculation option to view the properties. Find the property field "Trials" and set this to a higher value, such as 400. In many instances, this is enough to allow the program to find a viable solution. Note that the program will not necessarily run all 400 trials, but will only use the number of trials it takes to come up with a viable solution. Other options to try changing 1. Engine Compatibility. The latest solver is "WaterGEMS 2.00.12". If you are using an older solver, using the latest may help as well. 2.. Convergence Check Frequency. This option sets the number of solution trials that pass during the hydraulic balancing before the status of pump, check vlaves, flow controls valves, and pipes connected to tanks are once again updated. 3. Convergence Check Cut Off. This option is the number of solution trials after which periodic status checks on pumps, check valves, flow control valves, and pipes connected to tanks are discontinued. 4. Dampening Limit. This is the accuracy valve at which solution dampening and status checks on PRVs and PSVs should begin. Change the value so that it is 10 times the accuracy. So if you have an accuracy of 0.001, set Damping Limit to 0.01. If that doesn't work, you can also try to increase the Accuracy field (also in Calculation Options properties) to a higher value, such as 0.01. This will mean that the relative flow change between iterations can be higher, which may allow the program to find a solution. You do not want the accuracy value to be too high though, or it may compromise the results. If you are using linear interpolation, you can try setting this to False, as shown in the screenshot below. This can help in cases where the pump is part of the issue. Note that these options are only available for the "WaterGEMS 2.00.12" solver. More information on these can be found at the following support solution: Engine Compatibility modes and Calculation Options . See Also "Network Unbalanced" problems with zero flow/ static conditions Engine Compatibility modes and Calculation Options Using The Network Navigator Using Network Navigator's Powerful Queries
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Wiki Page: Why doesn't my load use type field show up in the "population density type" field
Applies To Product(s): WaterGEMS, SewerGEMS, CivilStorm, StormCAD, SewerCAD, HAMMER, WaterCAD Version(s): 08.11.XX.XX Area: Layout and Data Input Original Author: Jesse Dringoli, Bentley Technical Support Group Problem Why doesn't my load use type field show up in the "population density type" field in Loadbuilder? Why doesn't my land use type field show up in the "land type field" field in Loadbuilder? Problem ID#: 48669 Solution LoadBuilder expects the Land Use Type field to be a text field (not a numeric field). Some LandUse shapefiles just use a numeric code. If this is the case, you will need to convert your land/load use type field to a text data type.
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Wiki Page: No Profile name Exists: WaterGEMS. Will create Profile with default settings in WaterGEMS for AutoCAD
Applies To Product(s): WaterGEMS, WaterCAD Version(s): 08.11.xx.xx Area: Installation Original Author: Jesse Dringoli, Bentley Technical Support Group Problem When opening the WaterGEMS for AutoCAD shortcut, the following errors are encountered: "No Profile name Exists: WaterGEMS. Will create Profile with default settings" "Cannot find the specified drawing file. Please verify that the file exists." "Arquivos.scr" Can't find file." Solution This may be due to a problem with the target path in the shortcut. Special characters or extra spaces in the translation of "C:\Program files\ ..." may be cause the path to be unrecognized. To resolve this, first delete both the desktop and start menu shortcuts, then run the "Integrate WaterGEMS with AutoCAD...." shortcut, under the WaterGEMS start menu folder. If the same error is still encountered, wait until AutoCAD opens, then go to OPTIONS, the "profile" tab and set the "WaterGEMS V8i" profile to current.
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Wiki Page: How can I find water deceleration in a pipeline with a check valve?
Applies To Product(s): Bentley HAMMER Version(s): 08.11.xx.xx Area: Output and Reporting Original Author: Jesse Dringoli, Bentley Technical Support Group Problem How can I find water deceleration in a pipeline with a check valve? Solution First, run the Initial Condition analysis and record the velocity in the pipe downstream of the check valve. Let's assume it is 4 ft/second. Next, run the transient simulation and open the Transient Results Viewer. Plot a time history graph of flow in the pipe downstream of the check valve and measure the time from when the pump turns off until the flow curve crosses the x-axis (i.e. when flow reaches zero). Let's assume it is 2 seconds. So the deceleration of the water column is 4 ft/second / 2 seconds = 2 ft/s^2. This is an average deceleration rate, which is typically what valve manufacturers provide. See Also Finding Water Deceleration in Pipeline - Check Valve Slam Analysis Reverse Velocity vs. Deceleration curves for a check valve
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Wiki Page: How can you change the appearance of the profile in the Transient Results Viewer?
Applies To Product(s): HAMMER Version(s): 10.00.xx.xx, 08.11.xx.xx Area: Modeling Original Author: Scott Kampa, Bentley Technical Support Group Problem How can you change the appearance of the profile in the Transient Results Viewer? Solution After computing the model, open a profile in the Transient Results Viewer. Then go to the Settings button and chose Profile Options. After making the changes, select "Apply" and "OK". The appearance of the profile will then be changed to match the new settings. Next, select the Settings button again and chose "Save as Default Profile Settings." Be sure to save the project as well, or the default settings will not take. Now when opening a new or existing model, and then opening a profile, you can apply the settings by going to the Settings button and choosing "Apply Default Settings." The profile will then change to display the defaults set up earlier. The new profile settings will not automatically be displayed. Only after selecting "Apply Default Settings" will make the change. However, after saving the project, it should remain with these settings thereafter. Note that there is a file that should be updated with you save the default settings. If you browse to C:\Users\(user name)\AppData\Local\Bentley\HAMMER\10 (or 8)\TransientResultsViewerProfileSettings.xml, you should see that the file is updated to the date that you saved the file.
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Forum Post: Inlet Control for Storm Drains in StormCAD
I'm having some trouble figuring out if StormCAD runs an inlet control calculation for each pipe. I have a pipe that should be under well under capacity and would think it would be inlet control. But StormCAD reports an HGL well below the soffit of the pipe. The new version allows to indicate the pipe is a culvert and then it will run an inlet control calculation, but not sure if this is the best way to do it or the most accurate. When I use this it results in a much higher HGL at the US inlet, which I believe... I simply want to run an orifice calc to determine the HGL required to push it through the opening. I have see nowhere that I can set a default to check the inlet control on pipes. And if I have to use the culvert equation, what HW condition is most suitable?
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