Applies To Product(s): SewerCAD, SewerGEMS Version(s): 08.11.XX.XX, 10.XX.XX.XX Area: Modeling Original Author: Jesse Dringoli, Bentley Technical Support Group Problem In a model with high points that need to be accounted for with air valves (see Modeling Force Mains With Air Valves [TN] ) one or more of the following problems may be encountered: 1) Pressure results indicate the user notification "network unbalanced" 2) "system disconnected" user notifications are seen 3) The error "Unable to solve network hydraulics equations" occurs 4) Negative pressures 5) Generally strange or unexpected results seen (such as in profile view) Solution When using air valves in WaterCAD, WaterGEMS or SewerCAD (or SewerGEMS with the GVF Convex solver), and the property "treat as junction?" is set to "false", it is important to understand that additional complexity is introduced into the model. To summarize the information in this article, the presence of such air valves allow an upstream pump to "see" the high point and add enough head to overcome it, preventing otherwise negative pressures. Behind the scenes, these open air valves are essentially treated as a Pressure Sustaining Valve (PSV) with HGL setting equal to the air valve elevation. So, the model must calculate the approach head loss/drop across the element, which can be viewed in profiles as part-full flow just downstream of the air valve location. Since this loss/drop is calculated dynamically, if there are multiple open air valves, it can introduce instability as they attempt to achieve a balanced condition. Start simple - no air valves considered The first step in troubleshooting a challenging model with multiple air valves at high points would be to set all of the air valves' "Treat as Junction?" property to "true", then run the model to see which high points experience negative pressures. You may want to run several different model conditions that you will be studying (different steady state periods, control arrangements, peak vs average loads, etc) to ensure that you find the air valves that will be open during at least one of those modeling cases. Check basic data input in steady state Equally important, you should check that all of your data input is correct. With the air valves set to be treated as junctions, if your results are stable, you should be able to check some of the basic results (even if high points experience negative pressure) to ensure that everything is entered correctly. Do this with a steady state simulation to start. For example make sure that the pumps you expect to be on are turning on. If they are not, check their control range. It should be within the minimum and maximum elevation of the upstream tank/wetwell (and not equal to). If messages are encountered about a pump not being able to deliver head or flow, look at the profile view, pump operating point, pump curve and profile of the hydraulic grade line. Think about if the pump curve is correct or sized appropriately given what you see. If an unexpected headloss is seen in profile view, check the properties of the pipe and confirm the diameter, roughness, etc are set correctly. Also, if you are using check valves in pipes ("Has Check valve?" = "True") consider removing those for the sake of simplicity. This is because check valve also introduce complexity in the calculations and can "fight" against the air valves. The pump element already has a built in check valve, so pipe check valves can be redundant. Furthermore, ensure that your air valve nodes are added on the main line (in series with the pipes and junctions) and not at a tee with a lateral pipe. Once the basic input and steady state results are confirmed, try running an EPS to check if controls and varying loads/demands are working. If the model fails midway (for example "cannot solve network hydraulic equations"), try backing off the simulation duration incrementally until the model runs. This can help narrow down the time when the failure is occurring. Try graphing the "percent full" attribute of all tanks (Edit > Select by Element > Tank, right click > graph). If you see a tank about to become full or empty, this could potentially cause problems. In this case, check the tank in question and confirm that the related pump control is set correctly. Also check if the pump (or pumps) are able to keep up with the tank inflow. For example you might find that when the pump(s) are on, they cannot keep up with the upstream wetwell inflow and cause the wetwell to overflow. In this case, you may need to check the pump definition of the downstream system (which effects the operating point and thus pump outflow). Incrementally activate air valves as needed Once the basic data input has been checked, start enabling air valves one at a time. Start at the upstream end and work your way downstream for example, focusing on the high points that you anticipate would likely be open, setting the "Treat as Junction?" property to "false". Some care may be necessary here. For example if you have two high points, you may need to assess if only one of them would be open (pressure otherwise below zero). Try one at a time, compute the model in steady state, then check the results in a profile view of that area (for example between the upstream pump and downstream wetwell). You may find that due to part-full downstream flow (again, see this article for more on that), a nearby downstream air valve may also need to be set to "false" to prevent negative pressures. Add additional Air Valves as Needed Note that you may sometimes find that additional air valves may need to be inserted in the model. For example if you have a high point that consists of a few junctions all around the same, high elevation and the air valve is at the upstream side, the next-downstream junction may experience negative pressure. In this case, it may be that the air valve should be placed at the downstream side of the hill, so the HGL on the upstream side of the hill remains positive. For an illustration, see "Example 2" at the bottom of this article. Running EPS, Problems When Pump is Off After your steady state run is acceptable, continue on with an EPS (if you need to model one). If problems are noticed, they can be due to different conditions from a different combinations of pumps being on or off, or from differences in loading/demand compared to the steady state. Or, there could be problems with pump controls which may need to be checked. See Example 1 further below for an illustration of an example model with air valves, with good results with the pumps on and off. If the profile still does not look right when the pump is off, you can place an imaginary wetwell on a short branch with a tiny diameter pipe at an Elevation (Initial) equal to the air valve elevation. This wetwell (which will not contribute significant flow) can eliminate the disconnected system message and correctly represent the fluid in the upstream pipe when the pump is off. Please note that the wetwell will need to be connected to the upstream side of the air valve. When the upstream pump is off, you may still see negative pressures downstream of the high point, which may be interpreted as part-full flow (the pipe may drain out). An Alternative Approach - Gravity Conduits If you've used the above suggestions and are still running into problems, consider the possibility of using conduits and manholes instead of pressure pipes/junctions and air valves, for sections of the network that always experience part-full flow. Meaning, if there is an air valve that always remains open (pressure of zero in the model) with part-full flow in the downstream pipe, consider morphing the air valve into a manhole, with conduits going downstream to the wetwell. In the manhole properties, select the option for a bolted cover to allow for surcharging if needed. Or, use the Transition element instead of the manhole (as it represents an enclosed change from one pipe to another). Of course, this approach may not make sense in cases where an air valve is not always open (where in some conditions it is, and in others the pressure is positive.) Example 1 Model with air valves configured, pumps on: Same model, time step when pumps are off: Example 2 Air valve on upstream side of high point, negative pressure issue just downstream: Same network, air valve on downstream side of high point - better results: Downstream profile more accurate by adding additional air valves: See Also Modeling Force Mains With Air Valves (WaterCAD and WaterGEMS Modeling Force Mains with Air Valves (SewerCAD / GVF Convex Solver)
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Wiki Page: Troubleshooting Air Valves at High Points with the GVF Convex (SewerCAD) Solver
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Wiki Page: What does the "Unified length" / "Length (Unified)" field represent?
Applies To Product(s): SewerCAD, SewerGEMS, CivilStorm, StormCAD Version(s): 08.11.XX.XX, 10.XX.XX.XX Area: Other Original Author: Jesse Dringoli, Bentley Technical Support Group Problem What does the "Unified length" / "Length (Unified)" field represent in StormCAD V8i and SewerCAD V8i? Problem ID#: 41743 Solution The unified length field shows you the length that the program is actually using in the calculations. The reason is because there are several length fields available, which can cause confusion. For example, if you choose to use a user-defined length, the scaled length field will still show in the flextable and you may become confused as to which length each pipe is using. When preparing a report, if the model had a mix of user defined and scaled length pipes, you would not be able to report on either the scaled or user defined length. So, the Unified Length field can be used, since it will change to reflect the length used by that pipe. Meaning, if the pipe is set to use scaled length, it will display the scaled length. if it is set to use user-defined length, it will show the user defined length of that pipe. The other thing it does is round the pipe length based on the value entered under Tools > Options > Project > "Round Pipe Lengths to the Nearest". In the CONNECT edition this is Tools > Options > Hydraulic Model. In summary, if your pipe is set to use scaled length, the unified length field will show that scaled length, rounded to the value set in the options. The slope is based on that.
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Wiki Page: How to Batch Morph nodes from one type to another
Applies To Product(s): WaterGEMS, WaterCAD, HAMMER, SewerGEMS, SewerCAD, CivilStorm, StormCAD Version(s): 08.11.04.57 + Area: Modeling Original Author: Akshaya Niraula, Bentley Technical Support Group The Batch Morph tool allows you to morph a selected node type into another type of node element as a batch operation. Steps to Accomplish 1. Select the nodes to be morphed from the following choices: All: All nodes in the model will be morphed to the specified Target Element Type. Selection: Only the nodes that are currently selected in the drawing pane will be morphed to the specified Target Element Type. Selection Set: Only those nodes that are contained within the selection set specified in the drop down list will be morphed to the specified Target Element Type. 2. Check the Allow Morphing of Inactive Nodes? box if you want to include nodes set as Inactive in the batch operation. 3. Select the Target Element Type that the selected nodes will be morphed into. To morph Junctions into Isolation Valves: 1. Morph the desired junctions into TCV's, GPV's, or PBV's. 2. Use the Skelebrator "Inline Isolation Valve Replacement" operation . Workaround for older versions of the software For convenience, this solution will use "Element A" as the original node type and "Element B" as the new node type. The first step would be to export the properties of Element A, as well as the pipes in the model, into shapefiles. This can be done in the flextables for the individual elements by clicking the Export to File icon in the upper left. Next, you would need to delete Element A from the model. This will also delete the connecting pipe. You can select all of a certain type of element by going to Edit > Select by Element. Next, open Modelbuilder and import the shapefile for Element A. Go through the Modelbuilder steps until you get to the step where you map the features of the shapefile to the corresponding property. The element type will likely be default to be the same as Element A. However, you can change this to Element B instead. After mapping the shapefile features to the appropriate element properties, complete the Modelbuilder process. When you view the drawing, all of Element A should now be Element B. Next, go through Modelbuilder again, adding the pipes that were deleted back into the model. For more information on Modelbuilder, look at Help or the following Technote . The method above will allow you to replace all of a certain element with a different one. The one drawback to this method would be that there is a chance that some element properties will be lost in the process. If certain properties are not exported to the shapefile, or not properly mapped in Modelbuilder, you may lose some property information. If you try this method, I would still recommend reviewing the data to make sure that nothing was lost. See Also How to convert TCV GPV or PBV to Isolation Value using Skelebrator
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Wiki Page: Importing Demands From A Spreadsheet
Applies To Product(s): WaterCAD, WaterGEMS Version(s): V8 XM, V8i, CONNECT Edition Area: Layout and Data Input Original Author: Jesse Dringoli, Bentley Technical Support Group Overview This Technote describes the process by which a user can import demand information from a spreadsheet using Modelbuilder, into Junctions or Hydrants . This article assumes Bentley WaterCAD or WaterGEMS V8i (08.11.XX.XX). The process is slightly different in V8 XM (08.09.XX.XX). NOTE: if you'd like to include a visual representation of the customers associated with each individual demand, use the Customer Meter element instead. See this Webinar on the workflow of importing with Modelbuilder and using Loadbuilder to allocate to junctions. Background In WaterCAD and WaterGEMS, demands can be entered as a base flow plus a pattern, or as a unit demand type and count. Also, multiple demands can be entered for each node (junction, hydrant, etc.). An exception would be the Customer Meter element, which is used for a 1:1 representation of all demands. If your demand data is contained within an Excel Spreadsheet and you have a field that contains labels that match your model's node labels, you can use the Modelbuilder feature to import them. For example: Note: If your demands are in shapefile form and you want to import them into junctions or hydrants, you should use the Loadbuilder tool, which can utilize the spatial information contained in the shapefile to assign demands, using many different methods. If you attempt to import this information using Modelbuilder, you may end up with the following unexpected results: This is due to the user selecting "junction" as the table type, which only provides read-only "demand" attributes to link your data to. Preparation First, you should of course ensure that all your junctions and other elements are present in the model. When we import the demands from the spreadsheet, they will automatically update these existing elements. Next, if you have not done so already, you'll need to set up any demand patterns that you'll be using. These are typically diurnal curves that adjust the base demand over the course of the EPS simulation. Go to Components > Patterns. Create a new hydraulic pattern and enter the starting multiplier along with the table of time/multiplier: If you have a lot of demand patterns, see this article for how to import those with modelbuilder: Importing Demand Patterns Using Modelbuilder Open your source spreadsheet and ensure that it is formatted properly. Ensure that you have columns for the junction label, base demand and pattern, with a header at the top (see first illustration further above.) Ensure that the labels for your patterns match the ones in the source file that contains the loading data. If you would like to use a fixed pattern, simply enter "Fixed" under the pattern column for those junctions. (or, omit the pattern column altogether, if all junctions will have fixed demands.) Properly Importing your Demands in Modelbuilder Note that when you import demands using this process, they will override any previous demands assigned to those nodes included in the spreadsheet. So, this process cannot be used to 'update' an individual demand for nodes that have multiple items in the demand collection. All of the demands that should be present for a particular manhole should be included in the spreadsheet when using this process. Note: if you have WaterCAD or WaterGEMS V8 XM Edition (08.09.XX.XX) then the following Modelbuilder steps will be slightly different, as that version is older. The basic process is the same though. 1) Start a new modelbuilder run by going to Tools > Modelbuilder and clicking the white paper button. Select your data source type and then the file itself. Click the checbox next to the layer/worksheet that contains the data. You can click "show preview" to check the data in the later selected: 2) Click Next and uncheck the "create nodes if none found at pipe endpoint" check box: 3) Click Next and uncheck everything except for "update existing objects in destination if present in source". This is because we are updating elements, not creating or deleting them. 4) Click Next and accept the default "Current Scenario" and "Label". This is because we will be updating our current scenario and using the WaterCAD/GEMS label field. 5) Click Next to display the field mappings. This is an important step. First, click the layer on the left side (representing the worksheet containing your demands) and select "Junction - Demand collection" as the "Table Type". This is because the data that we are updating is not directly within the junction itself, but within the junctions' demand collection. A collection means that there are multiple items for each individual junction (composite demands are possible.) For example, you may have noticed that there are two individual demands for J-1 in the source spreadsheet shown in the first illustration. This is a composite demand. For the "Key fields", select the column header that you used for the labels (most likely "Label".) This is used to link the demand entries with the junctions in your model. In the bottom right corner, you must map fields in your spreadsheet to fields in WaterCAD/GEMS. This is because WaterCAD/GEMS cannot interpret your labels. For example, if you had a column called "Base_flow", there is no way for it to know that this means the Base Demand. 'Demand (Base)' - this should be mapped to your base demand column. Ensure that the correct units are selected. 'Pattern (Demand) (Label)' - this should be mapped to your pattern column 6) Click "next" and choose "yes" when prompted to build the model. You can uncheck the options concerning selection set creation. In the Modelbuilder Summary, you should receive a message stating that a certain number of your junctions were updated. 7) Close Modelbuilder and examine your demands. You can use the Demand Control Center (under the Tools menu) to easily view all demands: What if I have unit demands? If you have unit demands (unit demand label + count), you'll need to do a separate Modelbuilder run using a slightly different process. The unit demand information will need to be in a different worksheet in your spreadsheet (or a different spreadsheet altogether) with columns for the junction label, Unit demand, unit demand count and Pattern: Instead of defining patterns in your model, you'll need to first import the Unit Demand types, under Components > Unit Demands. Either click the "new" button and define them, or import some commonly used ones from the engineering libraries (purple book icon) In the last Modelbuilder step, you would select "Junction - unit demand collection" as the table type, instead of "Junction - demand collection". You would map the following fields 'Unit Demand (Label)' - this should be mapped to the column that represents the type of unit demand. 'Number of Unit Demands' - this should be mapped to the column that represents the 'count' of units. For example, if the unit demand is "Residential" with it's demand representing 1 house, then a 'count' of '10' would represent 10 houses. The program will multiply the unit demand by the count to acheive the total unit load. 'Pattern (Demand) (Label)' - this should be mapped to the column that represents the pattern associated with each unit demand. After Modelbuilder imports the data, you can view your unit loads in the Unit Demand Control Center, under the Tools menu. This tool will also show you the computed demand based on the unit demand and the "number of unit demands" (the count.) What if I want to place demands on hydrants? To import demands into hydrants instead of junctions, you would select "Hydrant - Demand collection" as the table type, instead of "Junction - Demand collection". Or, "Hydrant - Unit demand collection" if using unit loads. However, hydrants usually represent demands that would only occur during a fire (using the automated fireflow routine or emitter coefficient). So, demands are typically not assigned directly to them. What if I want to import demand patterns, too? Automated importing of demand patterns is only recommended if you have a large number of them that would otherwise take too long to enter (even with copy/pasting the columns of data). For steps to use Modelbuilder to import demand patterns, see this article: Importing Demand Patterns Using Modelbuilder What if I want to see every customer meter in the model? If you want to see every customer meter, instead of lumping multiple demands into a single node, use the Customer Meter element. See this Webinar on the workflow of importing with Modelbuilder and using Loadbuilder to allocate to junctions See Also Can demand data be exported to an Excel file for use in another model? Importing Demand Patterns Using Modelbuilder
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Wiki Page: User notification: "Pump Efficiency must be between X% and Y% inclusive."
Applies To Product(s): Bentley HAMMER Version(s): 08.11.xx.xx Area: Modeling Original Author: Jesse Dringoli and Scott Kampa, Bentley Technical Support Group Problem When computing the transient solver, the following error message occurs: "Pump Efficiency must be between 0% and 100% inclusive." However, the pump efficiency is between 0% and 100%. or "Pump Efficiency must be betweeen 30% and 95% inclusive" Solution In HAMMER, the efficiency for a pump during the initial conditions must be between 30 and 95%. The efficiency is different depending on the operating point of the pump. Go to Components > Pump Definitions, click your pump definition and look at the plotted efficiency for each operating point. In the properties of the pump element in question, look at the pump head and flow and compare that operating point with the pump curve to see what the efficiency is. The calculations behind HAMMER assumes that a pump's nominal operating point (derived from the initial conditions) is at or close to the best efficiency point, which is why you get that message. If the pump in question is off in the initial conditions and you want to have it start up, make sure you choose "Pump Startup" as the Transient Pump Type, then enter the Nominal Head and Nominal Flow corresponding to a good efficiency from the pump definition. This message cause also occur if there is zero initial flow in the initial conditions. This may cause incorrect efficiency values to be derived based on these erroneous results. Another possible cause is related to a setting in the transient calculation options. If the field "Specify Initial Conditions" is set to "True", you will need to make sure that nominal head and flow values are entered for any pump in the model. If not, the incorrect head and flow values will be passed to the transient solver and invalid efficiency values as well. In such a case, the simplest solution for such cases is to set "Specify Initial Conditions" to "False". Then you can compute initial conditions and get valid flow and head results. If you need to specify initial conditions, make sure that valid values for nominal head and nominal flow are entered for all pumps in the model. See Also WaterGEMS/WaterCAD user notification: "Network Unbalanced" What is the best way of modeling the best efficiency point (BEP) when modeling a pump in HAMMER?
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Wiki Page: Modeling the best efficiency point (BEP) when modeling a pump in HAMMER
Applies To Product(s): Bentley HAMMER Version(s): 08.11.xx.xx Area: Modeling Original Author: Scott Kampa, Bentley Technical Support Group Problem What is the best way of modeling the best efficiency point (BEP) when modeling a pump in HAMMER? There is an efficiency tab, but also a place to enter efficiency data in the Transient tab. Solution The efficiency of the pump is only being accounted for the in the Efficiency tab. In the Transient tab, the value entered for Brake Horsepower at Best Efficiency Point is simply the value for Brake Horsepower at the BEP set in the Efficiency tab.
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Wiki Page: "Unsupported dataset type schema" error or "Object Reference" error or "Unexpected drawing version:" when opening a model file
Applies To Product(s): SewerGEMS, WaterGEMS, WaterCAD, HAMMER, SewerCAD, StormCAD, CivilStorm Version(s): 10.00.xx.xx, 08.11.xx.xx Area: Data Input and Model Creation Original Author: Jesse Dringoli, Bentley Technical Support Group Problem What is the cause of the error message "Unsupported dataset type schema" , "Object Reference not set to an instance of an object", "Unexpected drawing version: XX " (where XX is some number) when opening a model file or submodel? Solution This error typically indicates that the model was created in a newer version of product. To find out what version the model was last saved in, open the .WTG or .STSW file (depending on the product) in a text editor such as Wordpad or Notepad and look for "ProductVersionLastModified=" near the top. This wiki provides an explanation of how to do that . You will need to install a version that is equal to or greater than this in order to open the model. If that is not possible, there are a few workarounds that you can try. Option 1 If you are using a version that is equal to or greater than the version last used to modify the model, then the issue could be related to one of the supporting files (eg. .out). Try copying the model file (.stsw, .wtg) and database file (.mdb, .SQLite) to a new folder. Then try to open the model from the new location (without using the supporting files). Option 2 If you have a Water products (HAMMER, WaterCAD, and WaterGEMS), export the model to the standard EPANET format (File > Export > EPANET). This format can be opened in most older versions by going to File > Import > EPANET. Note that there are limitations with this method such as only being able to export one scenario, and other items described in this wiki article related to EPANET importing and exporting. For SewerGEMS and CivilStorm, export the model to the EPA SWMM format (File > Export > SWMM v5). After that the SWMM file can then be opened by most older version of the software (File > Import > SWMM v5). As with the EPANET for the water products, you may also run into some limitations or have the potential to lose some information in the process of the export/import. In SewerCAD and StormCAD, you can export the model to the LandXML format (File > Export > LandXML) and import the LandXML file into the older version of SewerCAD or StormCAD. As with the water products, there may be some limitations to this workflow. Option 3 The other workaround would be to export all elements in your model to shapefiles and then import those shapefiles with the older version of the software using Modelbuilder. This method also will take some work though and can be tedious. The first thing you need to do if you are using this method would be to make sure your FlexTables have all the information you input for the properties of each element and then export each element to a shapefile. Export your elements to shapefiles is described in this wiki . After you do this you would need to use the ModelBuilder tool in the older version of the software (Tools > Modelbuilder) to import all those elements back in. Using ModelBuilder to construct a network is described in this wiki found below and there is also information in our Help documentation on how to use ModelBuilder See Also Can a model to saved down or back to an older version? 'Unexpected Numeric Presentation Formatter' or 'Expecting: Numeric Formatter or Station Formatter' error when opening model Error opening old model file: Database format not recognized or read-only
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Wiki Page: Locating the version number of the software a model was created using
Applies To Product(s): Bentley WaterCAD, Bentely WaterGEMS, Bentley SewerGEMS, Bentley SewerCAD, Bentley StormCAD, Bentley CivilStorm, Bentley PondPack, Bentley FlowMaster Version(s): 08.XX.XX.XX Environment: N/A Area: Other Subarea: Original Author: Mark Pachlhofer, Bentley Technical Support Group Deleted: https://communities.bentley.com/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/13294.unsupported-dataset-type-schema-error-or-object-reference-error-or-unexpected-drawing-version-when-opening-a-model-file These are the directions to locate the version number of the software your model file was created using. Background There are some cases where you have error messages such as, "Unexpected drawing version: 39" , where it helps to know what version of the software was used to create a model. Steps to Accomplish I will use WaterGEMS/CAD/HAMMER as an example here. Note that the file extension for the other programs is different, but you will only be opening the non-database project file (.stsw, .ppc, .swg, .swc, .csd, .fm8, or .stmc). Browse to the location/folder of the file that you want to view Right click on the .wtg file and select "Open with..." Now select some type of text editing software such as Notepad, Wordpad, Notepad ++, etc... Look for the third line of the file where it says, "ProductVersionLastModified =" and note the number of the software. See Also How do I download the latest versions of the Bentley hydraulics and hydrology products? Unexpected drawing version: 39 error when opening WaterCAD/GEMS or HAMMER
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Wiki Page: User notification: "Grate Length should be within the defined range of HEC-22's Chart 5 (approx. 0.5-4.5 ft / 0.15-1.35 m)."
Applies To Product(s): Bentley FlowMaster Version(s): 08.11.01.03 Area: Modeling Original Author: Jesse Dringoli, Bentley Technical Support Group Problem In a grate inlet on grade worksheet, why do I see the following message in the messages tab, even though results are computed? What does this mean? "Grate Length should be within the defined range of HEC-22's Chart 5 (approx. 0.5-4.5 ft / 0.15-1.35 m)." Solution The reason you get this message is because Flowmaster uses HEC-22 methodology for its inlet calculations, and a grate length greater than 4.5 feet is beyond the scope of the charts provided from HEC-22. Please open the HEC-22 manual (included with Flowmaster and located in its start menu folder) and turn to page A-10 and A-11, which show charts 5A and 5B. You will see that these charts do not go beyond 4.5 ft., so care must be taken when using grate lengths above this value, as extrapolation will be used. Basically the results may not be accurate as they are outside the bounds of the normal values used with the HEC-22 methodology. Results should be carefully checked.
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Wiki Page: Which dimensions are used when inputting grate information for inlets in StormCAD ?
, Product(s): StormCAD, CivilStorm, SewerGEMS Area: Layout and Data Input Original Author: Kathy Wiggins, Bentley Technical Support Group Problem Which dimensions are used when inputting grate information for inlets in StormCAD? Solution The user should reference the HEC-22 manual for detailed diagrams and/or information. This HEC-22 manual is found in the FlowMaster install folder typically found at "C:\ProgramFiles x86\Bentley\FlowMaster". When inputting the data (dimensions) of a grate, the user should use the dimensions of the entire grate itself. StormCAD automatically figures out the opening area (based on the type and external dimensions), using HEC-22, which has an opening ratio for each grate type.
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Wiki Page: Modeling surface ponding for overflow above multiple inlets
Product(s): CivilStorm, SewerGEMS Version(s): 10.00.xx.xx, 08.11.xx.xx Area: Modeling Background In some situations, multiple in-sag inlets may experience flooding and water will pond above them (for example a parking lot). How can this be modeled so as to have one common flooded area above multiple inlets? (multiple inlets sharing one surface storage) Surface Storage Approach The "Surface Storage" option in the catchbasin node element provides a way to store water above the rim elevation of the inlet. When using the surface storage option, when the HGL at the node rises above the rim elevation, flow will start to "spill" into the surface storage and the HGL will be allowed to rise further. However, the surface storage modeled with this option is kept separate for each inlet. Meaning, overflow for a particular inlet will only be stored in its respective surface storage and must drain back down into the respective node. If a gutter is attached, water will only pass down the gutter when the HGL reaches the maximum surface ponding elevation. See more here: When do channels receive flow vs. when gutters receive flow for a catch basin with surface storage? So, if you have multiple catchbasins that experience flooding at the same time and essentially create a single pond above them, and you would like to model this so that each inlet "senses" this single storage of water and handles it accordingly, you may need to use a Pond. Pond Approach With a pond approach, you would replace the inlets with pond outlet nodes, connected to a single pond. The pond elevation-area or elevation-volume curve would be set up to represent the in-sag area above the inlets that water would pond up in. Overflow from the catchbasin inlets would enter the pond and the change in storage and elevation would be communicated to each of the inlets. When the conditions warrant, water stored in the pond would recede back into the sub-surface network. The pond outlet node's "has control structure" property would be set to "true" and a Riser could be considered as the composite outlet structure. A riser simulates weir flow at low depths and orifice flow at submerged depths, similar to typical grate and curb inlets. In many cases you will have multiple sub-surface pipes (conduits) connected to the catchbasin. Since this is not permissible with the pond outlet node, a large diameter, short length pipe is suggested, between the catchbasin location and the pond outlet. The catchbasin in the model would be replaced with a manhole with a bolted cover ("Bolted Cover?" = True). With this setup, the hydraulic grade should be appropriately "communicated" between the pond and the pipe, though this could pose a hydraulically challenging situation, potentially requiring some calculation option changes. (see further below) The invert of the end of the conduit next to the pond outlet would be set equal to the invert of the sub-surface pipe leaving the catchbasin vault. The invert of the Riser outlet component and the bottom elevation of the pond would be set equal to the inlet elevation. A Note on Stability Note that the pond approach may be very hydraulically challenging for the numerical solver and may yield unstable results and/or high continuity error (as seen in the calculation summary). It is recommended that you try the Explicit (SWMM) solver (change this in the calculation options) with a small Routing Time Step for best results. If this does not help, consider approximating with individual surface storage in the properties of each catchbasin. In most cases, water may pond up at the same time for each of the inlets in question, so this may be an acceptable workaround and should be more stable. See Also Interpreting results when using manhole or catchbasin Surface Storage Troubleshooting unstable SewerGEMS and CivilStorm results using the implicit solver
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Wiki Page: Interpreting results when using manhole or catchbasin Surface Storage
Product(s): SewerGEMS, CivilStorm Version(s): 10.00.xx.xx, 08.11.05.58+ Area: Calculations Problem How do I interpret the results when using the surface storage option in a manhole or catchbasin, to check if surface storage is occurring and working properly? What does it mean when a positive value is seen for the "overflow" result field of a node that uses the surface storage option? Solution When the "Surface Storage Type" is set to "Default Storage Equation", "Ponded Area" or "Surface Depth-Area Curve", this models additional storage above the top of the node. For example it can be used to assess depth of flooding in a parking lot about a grate inlet in sag. When using the surface storage option, when the HGL at the node rises above the rim elevation, flow will start to "spill" into the surface storage and the HGL will be allowed to rise further. You can either graph the "Depth (Flooding)" result or graph Hydraulic Grade In and Rim elevation together with the "Flow (Total In)" and "Flow (Total Out)" result to visualize this. When using the Default Storage Equation or Surface Depth-Area Curve, you may see a positive value shown in the "Flow (Overflow)" result field. This overflow is lost from the system and indicates that the surface storage has been exceeded. For the Surface Depth-Area Curve, this happens when the flooding depth exceeds the maximum depth in the curve. For the Default Storage Equation, this occurs at a flooding depth above 2.0 ft (previously this was limited to 0.4 ft which you may see mentioned in the Help Documentation, but was recently increased). Note : Currently, the Ponded Area surface storage type is supported by the Explicit (SWMM) numerical solver. See Also Modeling surface ponding for overflow above multiple inlets
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Wiki Page: Issues with large surface storage at a node when the HGL level does not lower after reaching the maximum level
Applies To Product(s): CivilStorm, SewerGEMS Version(s): 08.11.XX.XX, 10.XX.XX.XX Original Author: Scott Kampa, Bentley Technical Support Group Problem When modeling surface storage using the surface depth-area curve for a large area, the HGL level does not lower after reaching the maximum level. The result is larger outflows than reasonable. Problem ID#: 36408 Solution The size of the surface storage is too large for the model to reach a solution for the calculations. The model is limited to a 10 acre surface storage area. There are couple of different workarounds for this. First, try using one of the default storage calculations. These calculations are detailed in the Civilstorm or SewerGEMS Help menu. Another workaround would be to model a smaller surface storage area. The area could also be modeled as a pond. There are several options available for this method. The first would be to model the manhole itself as the pond. The second would be to model the pond to the side of the manhole. In this version, the pond would essentially represent the storage area. This suggestion would involve connecting the manhole and pond via a pipe. This pipe could be varied in size in order to stabilize the model. Essentially, the overflow from the manhole would go through this pipe into the pond, with the idea that once the level in the manhole decreases, flow would go from the pond back into the manhole.
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Wiki Page: How do pumps work in the hydraulics and hydrology products?
Applies To Product(s): WaterGEMS, SewerGEMS, CivilStorm, SewerCAD, StormCAD, HAMMER, WaterCAD Version(s): 10.00.xx.xx, 08.11.xx.xx Area: Modeling Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem How do pumps work in the hydraulics and hydrology products? Solution WaterCAD/WaterGEMS/SewerCAD Pressure solver Pumps add enough head and the corresponding flow rate, which is defined on your pump definition curve, to overcome the losses and elevation differences between your upstream and downstream boundary conditions. Boundary conditions are tanks, pumps, reservoirs, and valves in the Water products and manholes, catch basins, outfalls, and wet wells, headwalls/endwalls in the SewerCAD. The pump operating point is where the pump curve intersects the system head curve. For more details on this please refer to this wiki . In the case of a closed system with only downstream fixed demands in WaterCAD and WaterGEMS, the operating point will be based on the demands. Essentially, it operates at the point where the pump characteristic curve intersects with the system head curve. You can read more about this in the book Advanced Water Distribution Modeling and Management Implicit SewerGEMS solver In SewerGEMS with the Implicit numerical solver, the downstream boundary is considered to be the crown of the pressure pipe where it meets the receiving gravity node, or any intermediate high point. GVF - Rational StormCAD solver When using StormCAD or the GVF-Rational solver pumps are now supported as ideal flow pumps as of Select Series 3 [08.11.03.77]), meaning that flow in will equal flow out and the pump curve is not used in the calculations. This solver does not support parallel pumping or pump controls. GVF - Convex SewerCAD solver When using the GVF Convex solver pumps will work the same as the pressure solver for pressure situations and will work the same as the implicit solver for gravity situations. When running a steady state the solver doesn't support pump controls. See Also A pump exceeds the maximum operating point user notification System Head Curves in WaterGEMS and WaterCAD
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Wiki Page: Is it possible to have a pump curve in the pump definitions use linear interpolation (go from point to point) instead of follow a curve?
Applies To Product(s): WaterGEMS, WaterCAD, SewerCAD Version(s): 10.00.xx.xx, 08.11.xx.xx Area: Modeling Original Author: Scott Kampa, Bentley Technical Support Group Problem Is it possible to have a pump curve in the pump definitions use linear interpolation (go from point to point) instead of follow a curve? Solution By default, the pump curves for WaterGEMS, WaterCAD, and SewerCAD follow a quadratic interpolation, giving the pump curve a smooth shape, as shown in the screenshot below. At times, a user might want a multi-point pump curve to follow a linear interpolation. This could be because the values in the pump curve may work better with a linear interpolation. For instance, there may be a large difference in flow for a small change in head. A user may also have pump data from a manufacturer that follows a linear interpolated pump curve and want the data in the model to match exactly. In such cases, there is a setting in the calculation options where a user can set a multi-point pump curve to use linear interpolation. To use this, open the calculation option properties by going to Analysis > Calculation Options, then double-clicking the active calculation option. In WaterGEMS and WaterCAD, find the section called Hydraulics and change the setting for the attribute "Use Linear Interpolation for Multipoint Pump Curves?" to "True". In SewerCAD, the same attribute can be found in the section called Pressure Hydraulics. It is important to note that if the "Use linear interpolation for multipoint pump curve?" set to False the software not only interpolates between the points you have defined on your curve, but also extrapolates points past the largest flow point you have defined until it reaches the point for the zero head. If the option for "Use linear interpolation for multipoint pump curve?" is set to True, then the software only reads the points that you have defined in your multiple point pump curve. This can be easily identified by setting the option in the calculations then accessing the pump definitions. Once you look at the pump definition notice the graph in the lower right portion of the window. When the option for "Use Linear Interpolation for Multipoint Pump Curves?" is set to False, you'll see the zero head point on the far right of the x-axis on the graph. When you have the option set to True, you will see the last point on the x-axis stop at the last point you have defined. Note: This only works for multi-point curves and not for three-point or one-point curves. If you are using SewerGEMS, the pump definition only follows linear interpolation , with both the Implicit and Explicit solver. However, the appearance of the pump curve uses quadratic interpolation. If a user wants to see the actual linear interpolation of the pump curve and has SewerGEMS SELECTseries 3 and later, there is an indirect way to change the appearance of the curves. To do this, first change the Active Numerical Solver in the calculation options from "Implicit" or "Explicit" to "GVF-Convex (SewerCAD)". The SewerCAD calculation option properties will then be available, including the attribute "Use Linear Interpolation for Multipoint Pump Curves". Change the setting of this property to "True", then change the Active Numerical Solver back to "Implicit" or "Explicit". The multi-point pump curve will not follow linear interpolation. With linear interpolation set, the pump curve will look like the screenshot below:
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Wiki Page: In the pump definition window, what are blue and red curves/lines in the graph window?
Applies To Product(s): WaterGEMS, WaterCAD, HAMMER, SewerCAD, SewerGEMS, CivilStorm Version(s): 08.11.XX.XX Area: Modeling Original Author: Nancy Mahmoud, Bentley Technical Support Group Problem In the pump definition window, there are blue and red curves/lines in the graph window. What are these? Problem ID#: 45261 Solution The default setting for this is that the blue curve is the Pump curve, while the red one is the Efficiency curve. See Also How do pumps work in the hydraulics and hydrology products? Is it possible to have a pump curve in the pump definitions use linear interpolation (go from point to point) instead of follow a curve?
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Wiki Page: Downloading Haestad / Hydraulics and Hydrology Software
Product(s): WaterGEMS, WaterCAD, Hammer, SewerGEMS, SewerCAD, StormCAD, CivilStorm, FlowMaster, PondPack, CulvertMaster Version(s): All This article provides information on how to download Hydraulics and Hydrology (Haestad) products. NOTE: Only your organization's designated site administrator(s) have the necessary permissions to download software from our website. Usually your site administrator is someone from your IT or Helpdesk department but, if you don't know who this is you can find out by calling 1-800-236-8539 (US and Canada) > option 3 for problems accessing a Bentley website including login and password issues. Steps to Accomplish 1) Sign in to the Fulfillment Center *If you are directed to a page about Bentley iWare (https://store.bentley.com/en/products/iware) this means you are not a site administrator and do not have the permissions to download the software. In this case please refer to the note in red located above. 2) Type in the product name and select the product. For example, you might type in: "HAMMER" or "Bentley HAMMER" 3) Click the “All Downloads” link, as shown in the screenshot below. 4) You should see a list of available versions of the product. If you do not see the product or you do not have access to the Download button to the left of the product name, you may not have rights to download and in such case please contact your local IT or call Bentley at 1-800-236-8539 (US and Canada) and choose option 3 for problems accessing a Bentley website including login and password. Note: The latest version of the software should be the first one in the list at the top. You can also tell the version by the third set of numbers after the period.The larger the number the more recent the version. For example 08.11.05.XX would be a more recent version than 08.11.04.XX and 10.XX.XX.XX is a more recent version than 08.XX.XX.XX. The latest two versions of the product are available to download. If another version of the product is needed, please contact Bentley Technical Support. Note: Typically you will only need the main installation file . The "Prerequisites for Bentley Desktop" and "i-model Publishing Engine" are only needed when you plan to export your model to an "i-model". 5) Click the green download button to the right of the item you are going to download. You will need to click each one individually. 6) Click accept on the terms of service agreement after you have reviewed it. 8) Finally, choose a location to save the file to. By default, on a Windows 7, 8 or 10 operating system or later, this would be: C:\Users\ \Downloads\ This will initiate the download process. The last step is to run the installation file(s) once saved. 9) Once the file is saved you'll be prompted to set the default license feature configuration of the software that you'd like to use. If you have an OpenAccess license you may want to consult with your IT / HelpDesk or person in charge of purchasing the software to see which configuration to use. The instructions below explain how to do that: Activate (license) Hydraulics and Hydrology Products See Also What is the installation order for WaterGEMS, WaterCAD, SewerGEMS, SewerCAD, StormCAD, PondPack, and CivilStorm? Cumulative patch set information and software update information What is an i-model and why does it show as a prerequisite? How do I publish an i-model? Original Author: Akshaya Niraula, Bentley Technical Support
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Wiki Page: Error message when opening up FlowMaster
Applies To Product(s): FlowMaster Version(s): 08.11.01.03 Area: Modeling Original Author: Akshaya Niraula , Bentley Technical Support Group Problem Description When opening FlowMaster V8i SelectSeries 1, the following message is generated: --------------------------- AccessViolationException Details --------------------------- Press Ctrl-C to copy details to clipboard:System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt. at DAO.Workspace.Close(Workspace* ) at CDaoDatabase.Close(CDaoDatabase* ) at Haestad.Domain.DaoInterop.DaoDatabase.Close() at Haestad.Domain.LibraryObjects.JetAppSettings.Dispose(Boolean disposing) at Haestad.Domain.LibraryObjects.JetAppSettings.Finalize() --------------------------- OK --------------------------- Solution This issue is related to a corruption in the engineering libraries. Follow the steps in the following article: How to Delete Engineering Libraries See Also When opening FlowMaster V8i on a Windows 8 computer the software hangs
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Wiki Page: Check Out of License not working in License Management Tool
Applies To Product(s): WaterGEMS, WaterCAD, PondPack, CulvertMaster, PondPack, FlowMaster, SewerGEMS, SewerCAD, CivilStorm, StormCAD Version(s): 08.11.XX.XX, 03.03.00.04 Area: Licensing Original Author: Terry Foster, Bentley Technical Support Group Problem Description The description below uses WaterGEMS as an example. When opening the License Management Tool to check out the WaterGEMS license the user clicks on WaterGEMS in the top window, then clicks on Check Out. The user keys in the email address and the expiration date is set for a year later. WaterGEMS shows up in the bottom window as checked out for a few moments then disappears. or When trying to activate a product as a non-SELECT user on the license check out page the product name is incorrectly populated or the version number is inaccessible. Steps to Resolve Option 1 Go to Start > All Programs > Bentley > WaterGEMS. Right-click on License Management Tool and select Run as Administrator. Option 2 Go to the install folder for WaterGEMS "C:\Program Files (x86)\Bentley\WaterGEMS" and locate the "LicenseTool.exe" file. Right click on it and run it as an administrator. Option 3 Uninstall and Reinstall the software using the directions from this wiki and perform the license clean up steps located at the bottom of the wiki. See Also Activation_of_Client_Side_Products and Registry Basics
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Wiki Page: Getting data and setting up for a Constituent Analysis in WaterGEMS and WaterCAD
Product(s): WaterGEMS, WaterCAD Version(s): 10.xx.xx.xx, 08.11.xx.xx Area: Modeling Introduction This article has general information on getting ready to run a constituent analysis in WaterGEMS or WaterCAD. You can also find a Quick Start Lesson related to running water quality analyses, including constituent runs. In addition, Example1.wtg (located in the Samples folder within the product installation folder) has a scenario related to running a constituent analysis. This article will walk through some general steps on getting the necessary information to get started. Background A constituent analysis is a type of water quality analysis that allows you to track the the concentration of a particular constituent at a given point in the network, over time. To compute a constituent analysis, you need to set the Calculation Type to "Constituent" in the calculation options, and configure the Constituent alternative. A calibrated, extended period simulation (EPS) model is a good starting point for water quality modeling. An EPS run should be used because this will account for mixing and storage in tanks and reservoirs, which is a contributing factor to the degradation of water quality in a system. In addition, chemical reactions depend on pipe flows, pathways and the time that the water is in the system. A steady sate run will not account for these to the extent needed. The information that you will include for a constituent include the diffusivity, the bulk reaction, and the wall reaction. For the diffusivity, you should be able to find default values in various documentation. Example1.wtg includes a couple of constituents where you may be able to find the diffusivity, if you could not obtain this value from another source. However, the bulk and wall reaction is something that is best determined within your specific system. Getting these values will likely require field studies and lab analyses. Bulk reaction data is typically determined through laboratory testing. Bulk reaction coefficients can be determined using an experimental procedure called a bottle test. A bottle test will find the bulk reactions by separating from other processes that may impact water quality and evaluated as a function of time. Determining the length of the bottle test and the frequency you take samples is critical to having accurate data. Typically, the duration of the test should reflect the transport time that occurs in the system. For instance, if a water age analysis of the model indicates a range of 5-7 days, a 7-day bottle test would provide bulk reaction data for the entire range. The frequency of sampling is related to the rate of the reaction. In a typical case, sampling should be more frequent early in the test and can gradually be decreased later in the time range. If the constituent in the bulk fluid has a first-order reaction, it will plot as a generally straight line on a semi-log graph and allow you to determine the bulk reaction rate. Wall reaction data is typically found from field studies. They are more difficult to ascertain than bulk reaction coefficients. Wall reaction coefficients are similar to pipe roughness coefficients in that they can vary from pipe to pipe. wall reaction coefficients cannot be directly measured, so they must be found from results in the field. This can sometimes be difficult. In such cases, you can test different values of the wall reaction coefficient against field data using time-series data. If you see values in the model that do not match up will with the field test data, you can adjust the wall reaction coefficient until you see better results. In addition to the bulk and wall reaction, you will need accurate initial information, including concentrations at the sources. Having accurate reading for concentrations, along with reasonable values for bulk reaction coefficients, wall reaction coefficients and diffusivity, will better assure accurate results in your modeling results. For more in-depth information on water quality modeling, as well as additional information on the steps listed above, please see the Advanced Water Distribution Modeling and Management book . You can find Quick Start Lessons related to water quality runs, including constituent analyses, in the Help documentation. See Also Modeling DBP formation - Water Quality Analysis What is the difference between the different Constituent Source Types used in a Constituent analysis? Analyzing concentration of multiple constituents, or a multi-point trace
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