Product(s): Bentley PondPack Version(s): 08.11.XX.XX Environment: N\A Area: Modeling Subarea: N\A Problem What options do I have to model a channel between two ponds? Problem ID#: 39298, Solution 1) If the water surface in the channel does not have the possibility of backing up and affecting the pond discharge, then model the outlet structure of the upstream pond as a free outfall. The outlet link will connect to a junction, which would then connect to a conduit. The conduit should be configured with the geometry of your channel and will connect to an outfall. The outfall will connect to the downstream pond. 2) If the channel water surface could effect the upstream pond discharge, but not to the point of reverse flow, then model the tailw ater condition of the upstream pond's composite outlet structure as "downstream channel". Then, select the channel geometry. This will cause the outlet structure rating curve to account for the tailwater of the channel. 3) If the channel water surface could potentially back up into the upstream channel, then you must use the Interconnected Pond Modeling (ICPM) feature. However, a channel cannot be used downstream of an ICPM route. So, you would need to either model the channel as a third pond, or add a 'fake' pond on the upstream end of the channel (conduit), with a free outfall control structure with a rating curve based on that channel's rating curve. Please see the "ICPM Channel.ppc" example model (within the "Samples" folder under your Pondpack8 installation folder) to see how this would be set up. See Also Original Author: Jesse Dringoli
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Wiki Page: How to model a channel between two ponds
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Forum Post: RE: Weirs design problems
Here are some suggestions for an improved solution using the Implicit solver. Remove the control on "Waste water conduit". This control is redundant because the orifice diameter in the control is the same as the pipe diameter. Remove the control on conduit "Rainwater Outlet". Create a weir by completing the following: Split conduit "Rainwater Outlet" with a transition Before: After: Transition Properties: Conduit/Weir Properties: 1. Remove headloss due to the conduits' bend angle at the transition. Set the field "Has User Defined Bend Angle?" to True Set the field "Bend Angle (User Defined)" to 0 degrees. 2. Set the conduit upstream of the transition to have section type Irregular Closed Section 3. For this example, I calculated the Chord Length for incremental elevations to create the cross section. Copy the following Elevation and Chord Length values (calculated in Excel) and paste them into the Depth Width Curve's Elevation and Width fields. Invert Elevation = 1739.74 m Weir Height = 0.1 m Radius = 0.75 m Elevation = Distance from Center + Height Chord Length = 2*SQRT((Radius^2)-(DistanceFromCenter^2)) Height Distance from Center Elevation Chord Length 0.1 0.65 1739.84 0.7483 0.15 0.6 1739.89 0.9000 0.2 0.55 1739.94 1.0198 0.25 0.5 1739.99 1.1180 0.3 0.45 1740.04 1.2000 0.35 0.4 1740.09 1.2689 0.4 0.35 1740.14 1.3266 0.45 0.3 1740.19 1.3748 0.5 0.25 1740.24 1.4142 0.55 0.2 1740.29 1.4457 0.6 0.15 1740.34 1.4697 0.65 0.1 1740.39 1.4866 0.7 0.05 1740.44 1.4967 0.75 0 1740.49 1.5000 0.8 0.05 1740.54 1.4967 0.85 0.1 1740.59 1.4866 0.9 0.15 1740.64 1.4697 0.95 0.2 1740.69 1.4457 1 0.25 1740.74 1.4142 1.05 0.3 1740.79 1.3748 1.1 0.35 1740.84 1.3266 1.15 0.4 1740.89 1.2689 1.2 0.45 1740.94 1.2000 1.25 0.5 1740.99 1.1180 1.3 0.55 1741.04 1.0198 1.35 0.6 1741.09 0.9000 1.4 0.65 1741.14 0.7483 1.45 0.7 1741.19 0.5385 1.5 0.75 1741.24 0.0000
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Forum Post: RE: Weirs design problems
Here is the profile after making the above changes.
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Forum Post: Darwin Calibrator Fitness Number
What is an acceptable fitness number when using Darwin Calibrator? At the moment the model I am trying to calibrate has a fitness number of 13.456. Initially it was in the 70's, but I have been playing around with tank elevations and the pump status as boundary overides since I do not have that information from the flow tests. Thank you, Ryan
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Forum Post: RE: Non-zero flow in closed pipes next to hydropneumatic tanks
I've uploaded the folder to Sharefile. It's called Water Model_RJT.zip. Another issue I've been having has to do with the pressures and liquid volumes in the hydropneumatic tanks. Each tank is supposed to have an operating pressure range of 40 - 60 psig. A volume of 31.3 gallons of water is supposed to be discharged from each tank when dropping in pressure from 60 psig to 40 psig. However, the graphs keep showing a liquid volume range of 10 - 15 gallons only. The pressures in the tanks also don't correlate with the operating pressure range. Each tank has a total volume of 115.9 gallons and a maximum drawdown of 70.5 gallons. If you know of a way to correct these issues as well, I would greatly appreciate it. Thanks, Rob Tejano
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Wiki Page: Why do I sometimes see a negative flow through a pipe?
Applies To Product(s): Bentley WaterGEMS, Bentley WaterCAD Version(s): 08.11.XX.XX Environment: N/A Area: Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem Why do I sometimes see a negative flow through a pipe? Solution A negative flow value indicates orientation of the flow with regard to the orientation of the pipe itself. The flow arrow symbol on the pipe in the plan view always indicates the direction of flow, and the orientation of the pipe itself is indicated by the "Start node" and "Stop node" fields in the pipe properties. If water is flowing from the "start node" to the "stop node", the flow arrow will point that way and the flow result value will be positive. If water is flowing from the "stop node" to the "Start node", the flow arrow will point that way and the flow result value will be negative. The absolute value of the flow result field is always indicative of the flow rate through that pipe, but a negative sign will be added to indicate direction. The reason why this behavior occurs is because in some systems, flow can often reverse direction over the course of a day. Showing the negative sign in front of the calculated flow value is one way for the user to distinguish the current direction of flow. In general, it is recommended that you lay out pipes in the direction that water will generally/usually be flowing, so that the calculated flows will be positive for most pipes. If you need to reverse the orientation of the pipe, you can do so by using the "Node Reversal" field at the top of the pipe properties. The following wiki shows how this can be done . Note that you can see the absolute value of flow through the pipe by looking at the "flow (absolute)" field in your pipe FlexTable. As you might expect, this basically removes the negative sign from the value seen in the "flow" result field. See Also How do I reverse the start and stop node for a pipe, conduit, gutter, etc...?
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Wiki Page: Paging file is too small for this operation to complete
Applies To Product(s): Bentley SewerGEMS, Bentley SewerCAD, Bentley CivilStorm, Bentley StormCAD Version(s): 08.11.xx.xx Environment: N\A Area: Calculations Subarea: N\A Original Author: Jesse Dringoli, Bentley Technical Support Group Problem When trying to compute a model, the following error occurs: "The paging file is too small for this operation to complete" Problem ID#: 65634 Solution Try adjusting your Windows page file setting: 1.) Start, Control Panel, System 2.) The system properties applet will appear, Select the advanced tab 3.) In the performance tab, click settings 4.) The performance dialog will appear, click the advanced tab click the change button 5.) You will now (assuming that you are a local admin) be able to increase the size of you virtual memory. 6.) Change the paging size and click set. 7.) Click OK 8.) Click OK 9.) Click OK 10.) At this point the machine may need to re-start. Also, make sure you have sufficient free disk space on the hard drive used to store the Windows temporary folder. (typically the C:\\ drive)
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Forum Post: RE: Darwin Calibrator Fitness Number
Hello Ryan, There isn't really a good rule of thumb for what a good fitness value is, aside from knowing that the lower the fitness number, the better (closer to field data.) You may need to use some engineering judgment to assess your latest trial. You can examine the solution results (model results vs field data, modified roughness/demand/status, and/or export the solution to the model and take a closer look. You may conclude that the results are good, with possible a few manual tweaks. Or, you might decide that further calibration is necessary, to get the fitness even lower. Calibrator has some options as far as how the fitness number is calculated, and the Help explains how it is calculated. See help topics "Calibration Criteria" and "Calibration Criteria Formulae". There are also some other tips under the topic "GA-Optimized Calibration Tips". Related forum thread: Head and Flow per fitness point
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Forum Post: RE: Non-zero flow in closed pipes next to hydropneumatic tanks
Hello Rob, It looks like the zip file only contains the .WTG file. Please include the .WTG.SQLITE file as well, as both are needed to open the model. In the meantime, some general suggestions - if the hydropneumatic tanks are offline or "float" on the system, try setting the "treat as junction" property to "true", for the appropriate scenarios. For the other issue - try a smaller calculation timestep. This tends to be the cause of many EPS problems with hydropneumatic tanks. See also: How are surge tanks and hydropneumatic tanks (hydro tanks) used in WaterGEMs and WaterCAD models?
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Forum Post: Tank below GL
Hi all i worked in project in KSA the system of water pipe network is that every house contains an under ground tank "below street level" and my mission is to deliver water to every tank knowing that number of houses "ground tank" about 42000 tanks which is the best way to model this : 1.only pipe and junction "knowing that pressures at junction is not true bigger than the truth" 2.ground tank on each house "how to model very big number of ground tank" 3.another way thanks alot
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Forum Post: RE: Non-zero flow in closed pipes next to hydropneumatic tanks
I've re-uploaded the folder (same folder name) with the .WTG.SQLITE file. Let me know if you need anything else. Thanks.
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Forum Post: RE: Tank below GL
Hello, It is always best to to have models closely represent the real system. How these underground tanks to the distribution system? Do they have individual pumps? If yes, would you like to model the individual pumps as well? It would be best model all the tanks, but it will take time to set up all the information for these tanks, like min , max levels etc. and apply demands and patterns to the tanks itself. Also if you have customer meter data with you, you can add the customer meters with demands and patterns to the model and connect them to the tanks. Or you could just model each house (or even a group of houses) as one junction. The advantage of this is that it should take less time to set up the model (since you don't have to enter a number of tanks, tank levels, etc.), and the model will be less complicated. This will give you the outline of the pressures at those points. Regards, Sushma.
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Forum Post: RE: Weirs design problems
Thanks for your help.
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Wiki Page: Can I easily export my results to an Excel spreadsheet?
Applies To Product(s): WaterGEMS, HAMMER, WaterCAD, SewerGEMS, SewerCAD, StormCAD, CivilStorm Version(s): 08.11.XX.XX Environment: N/A Area: Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem Can I easily export my results to an Excel spreadsheet? Can I export results to an Excel spreadsheet for all the time steps in my analysis? Solution Export from Flextables The first and most basic method of exporting model results to Excel is to use the Export button in the top-left corner of any Flextable. From here, choose CSV as the file type and the table will be exported to a CSV file that can be opened in Excel. Make sure to add or remove columns as needed before export. You can set up a new Project-Level flextable first if you don't want to modify the predefined flextables. Note that with this method, calculated / results fields will export the values for the current timestep only. To export all timesteps, see the next method below. Export from File Menu Previously, data could be exported to Excel via the Flextables, but needed to be done one Flextable at a time and did not include time series (results over time). Now, starting with V8i SELECTseries 6 (08.11.06.58+) of WaterCAD, WaterGEMS and HAMMER, and V8i SELECTseries 5 (08.11.05.58+) of SewerGEMS, SewerCAD, StormCAD and CivilStorm, we have added the ability to export data for all the element types at once, including time series. Steps: Go to, File > Export > Export to Excel. In the Export to Excel dialog, specify properties and elements to be exported by clicking the check boxes. Click OK. Note: these settings will be saved for the next export In the FlexTable Export dialog, select either Excel or CSV format and specify where it will be exported. On the lower left side of the dialog box you can also choose to export all elements, elements by a selection set, exclude inactive elements, or publish a subset of elements based on the active Flextable filters. Click OK. ModelBuilder Method Another possible method would be to use ModelBuilder to populate a spreadsheet. First, create a new spreadsheet with headers for the data you want to export in the first row of the spreadsheet. The element "Label" should be one of these. Save this spreadsheet, then open the model. Note that if you have a 64-bit computer and a 32-bit version of Microsoft Office, you will need to open the 32-bit version of the program. You can find this executable at "C:\Program Files (x86)\Bentley\ \ .exe". (such as WaterGEMS.exe for WaterGEMS) Compute the model and then open ModelBuilder. Select the New button. For the Data Source type, choose Excel and select the spreadsheet you just created. Click Next. In the next screen, make sure the units are accurate and click Next. Then click Next two more times. You should be on the field mapping section. For the Table Type, choose the element type the spreadsheet is for. For the key field, choose Label. In the lower right, you will see the column headers from your spreadsheet. Highlight on these and choose the appropriate results field from the Property pulldown menu (make sure the units are correct as well). Continue this until you have selected all of the items you want to export. Click Next. For the option "Would you like to build model now?" select No. After selecting No, click Finish. This will take you back to the ModelBuilder Manager. You should see the title of your spreadsheet listed in the list of ModelBuilder connections. Highlight this and select the Sync Out button. This will update the spreadsheet with the data from your model. Save this file. Now that the connection is created, each time you compute, you would simply need to open ModelBuilder, choose the connection and click Sync Out. Please note that the export from to Excel from file menu is actually easier to use than Modelbuilder method. We highly recommend using that instead of ModelBuilder to speed the process. You could also use a similar process for exporting your information to an Access database or another database format that ModelBuilder exports to.
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Wiki Page: When do channels receive flow vs. when gutters receive flow for a catch basin with surface storage?
Applies To Product(s): Bentley CivilStorm, SewerGEMS Version(s): 08.11.XX.XX Environment: N\A Area: Calculations Subarea: N\A Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem When do channels receive flow vs. when gutters receive flow for a catch basin with surface storage? Problem ID#: 59630 Solution Channels receive flow when the HGL reaches the catch basin rim elevation. The gutter doesn't receive flow until the HGL reaches the maximum surface ponding elevation
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Wiki Page: Disconnected network user notification
Product(s): Bentley WaterGEMS, Bentley WaterCAD, Bentley HAMMER Version(s): 08.11.XX.XX Environment: N\A Area: N/A Subarea: N\A Problem I'm getting a disconnected network user notification and I don't understand why. Is there anything that might help fix this? Problem ID#: 65979 Solution Sometimes this issue can be fixed by going into you calculation options and changing the Convergence Check Frequency option from the default of 2 to a greater number. If the engine is having difficult time converging on a solution thing engine tweak may be just what it needs to be given the step in the right direction at arriving at a proper solution.
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Wiki Page: Modeling Neenah Grate Inlets
Applies To Product(s): Bentley StormCAD, Bentley SewerGEMS, Bentley CivilStorm Version(s): 08.11.xx.xx Environment: N/A Area: Modeling Subarea: Original Author: Sushma Choure, Bentley Technical Support Group Background The Neenah Foundry Company (Neenah, Wisconsin - http://www.nfco.com) produces an extensive range of storm water inlets/catch basins, commonly referred to as 'Neenah grates'. These Neenah grates are not currently included in the default Engineering Libraries, but in Haestad products it is quite straightforward for users to add them as required. Steps to accomplish To Model a Neenah Grate for On Grade Inlets: Click the Components menu and then select Inlet Catolog . In the Inlets Catalog dialog, click New . Type a name for the new inlet. Note : We suggest using the Neenah catalog number and the transverse and longitudinal slopes that the curve capacity value will correspond to. Unlike in HEC-22 calculations, there is no general relationship available for Neenah grate capacity versus longitudinal slope, so each Neenah grate is entered in Haestad products as Kerb Channel Depth vs. Captured Flow’s curve which is specific to a particular transverse and longitudinal slope. Next click Inlet Type and select Kerb Channel Depth vs. Captured Flow . Enter the below ground Structure Width and Structure Length . Now refer to the Neenah technical information to find the K value associated with this grate (for the appropriate transverse and longitudinal slopes). For this example, for a longitudinal slope of 2% and a tranverse slope of 5%, use a K value of 16 . Then a depth versus captured flow relationship can be determined using the equation: Q=K.D^(5/3) . So: Table 5-3: Depth vs. Flow Values Depth (ft) Flow (cfs) 0.00 0.00 0.05 0.11 0.10 0.34 0.15 0.68 0.20 1.09 0.25 1.59 0.30 2.15 0.35 2.78 0.40 3.47 0.45 4.23 0.50 5.04 Now this relationship can be copied and pasted into the Kerb Channel Depth vs. Captured Flow area of the Inlet editor. To do this, copy the data to the windows clipboard, then in StormCAD, select the top right cell in Kerb Channel Depth vs. Captured Flow grid and press Ctrl+V to paste. Note : Make sure the units used in the inlet editor match the units used in determining the Depth vs. Captured Flow relationship. The inlet is now set up and ready to use in the current Haestad project. To make it available for use in other projects, click on the Synchronization Options button and select Export to Library. To know how to add entries to Engineering Libraries, please see the below support solution. Note : For on-grade inlets, software solves for the corresponding upstream gutter depth & with the help of K value it looks for the corresponding captured flow on the gutter depth vs.captured flow curve. On-grade inlets depend specifically on the transverse & longitudinal slope. So users have to be careful that the curve they use is suitable for the inlet conditions, ultimately K value should be chosen appropriately. To Model a Neenah Grate for In Sag Inlets: For rectangular grates in sag, it is generally possible to enter a Neenah grate as a standard Grate Inlet Type . However, please note that the Haestad products use the HEC-22 methodology for computing capacity, which does not always produce capacities that correspond to capacities given by Neenah Foundary (since some discharge coefficients are slightly different). The designer should verify that they are satisfied with the calculated capacity in these cases. For non-rectangular grates, the designer should compute, or request from Neenah Foundry, a Kerb Channel Depth vs. Captured Flow relationship for the grate and then enter that in Haestad software using a procedure similar to the procedure outlined for Inlets On Grade above. Note that the capacities of grate inlets in sag are not a function of the transverse of longitudinal slopes, so one Kerb Channel Depth vs. Captured Flow curve per grate is sufficient for all transverse and longitudinal slopes.
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Wiki Page: What is the "Travel time" result field, and why can it sometimes not be graphed?
Product(s): Bentley WaterGEMS. WaterCAD Version(s): 08.11.XX.XX Environment: N\A Area: Output and Reporting Subarea: N\A Problem What is the "Travel time" result field, and why can it sometimes not be graphed? Problem ID#: 68103 Solution The "Travel Time" field shows the time that it would take for water to travel from one end of the pipe to the other at the current velocity. Basically it's the length of the pipe divided by the velocity. As can be done with any field, you click it in the properties window and see a short description at the bottom of the properties. Although you may be able to graph this, there may not always be a valid value. For example if the flow is zero (from a pump being off), then the "Travel time" will be "N/A" and cannot be accurately graphed. It may be best to look at the value shown in the properties before attempting to graph it. It may also be worth looking at the value in the properties for several timesteps since it could certainly change over the course of an EPS. This can be done using the "Time Browser" under the Analysis menu. See Also
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Wiki Page: Why is it that no matter how large the inlet on grade is the gutter spread always remains the same?
Product(s): SewerGEMS, CivilStorm, StormCAD Version(s): Varies Environment: N\A Area: Output and Reporting Why is it that no matter how large the inlet on grade is the gutter spread always remains the same? HEC-22 inlet computations are concerned with when the gutter spread is maximum, which is immediately upstream of the inlet (see image below). Just downstream of the inlet, the spread is at its minimum because most, if not all, of the water has been intercepted. The spread is calculated for the flow in the gutter immediately upstream of the inlet, so the size of the inlet does not impact the width of the gutter spread. To remedy this situation, try increasing the size of the inlet(s) upstream of the inlet you have been working on. Original Author: Craig Calvin
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Forum Post: vulnerability of drinking water network
Hello, I would like to ask if there is any automatic way, similar as fire flow analysis, to evaluate the risk of damage of a network fail. As damage of a network fail, I refer, the part of the network (and clients) affected because some pipe need to be out of service for any reason. We are thinking to analyze main stream pipes, especially those at the beginning of the network, coming out from tanks. Thanks for any help.
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